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* [PATCH v5 00/10] xen/arm: Add support for SMMUv3 driver
@ 2021-01-20 14:52 Rahul Singh
  2021-01-20 14:52 ` [PATCH v5 01/10] xen/arm: smmuv3: Import the SMMUv3 driver from Linux Rahul Singh
                   ` (9 more replies)
  0 siblings, 10 replies; 24+ messages in thread
From: Rahul Singh @ 2021-01-20 14:52 UTC (permalink / raw)
  To: xen-devel
  Cc: bertrand.marquis, rahul.singh, Stefano Stabellini, Julien Grall,
	Volodymyr Babchuk, Andrew Cooper, George Dunlap, Ian Jackson,
	Jan Beulich, Wei Liu, Paul Durrant

This patch series is v5 of the work to add support for the SMMUv3 driver.

Approach taken is to first merge the Linux copy of the SMMUv3 driver
(tag v5.8.18) and then modify the driver to build on XEN.

MSI and PCI ATS functionality are not supported. Code is not tested and
compiled. Code is guarded by the flag CONFIG_PCI_ATS and CONFIG_MSI to compile
the driver.

Code specific to Linux is removed from the driver to avoid dead code.

Driver is currently supported as tech preview.

Following functionality should be supported before driver is out for tech
preview
1. Investigate the timing analysis of using spin lock in place of mutex when
attaching a  device to SMMU.
2. Merged the latest Linux SMMUv3 driver code once atomic operation is
available in XEN.
3. PCI ATS and MSI interrupts should be supported.
4. Investigate side-effect of using tasklet in place of threaded IRQ and fix
if any

Changes since v4:
[PATCH v5 10/1]:
 - Replace the ffsll() with ffs64() function.
 - Add code to free resources when probe failed.

[PATCH v5 08/10]:
 - Add more information about the merged patch in commit message.

Rahul Singh (10):
  xen/arm: smmuv3: Import the SMMUv3 driver from Linux
  xen/arm: Revert atomic operation related command-queue insertion patch
  xen/arm: smmuv3: Revert patch related to XArray
  xen/arm: smmuv3: Remove support for Stage-1 translation on SMMUv3.
  xen/arm: smmuv3: Remove Linux specific code that is not usable in XEN
  xen/device-tree: Add dt_property_match_string helper
  xen/compiler: import 'fallthrough' keyword from linux
  xen/arm: smmuv3: Use fallthrough pseudo-keyword
  xen/arm: smmuv3: Replace linux functions with xen functions.
  xen/arm: smmuv3: Add support for SMMUv3 driver

 MAINTAINERS                           |    6 +
 SUPPORT.md                            |    1 +
 xen/common/device_tree.c              |   27 +
 xen/drivers/passthrough/Kconfig       |   11 +
 xen/drivers/passthrough/arm/Makefile  |    1 +
 xen/drivers/passthrough/arm/smmu-v3.c | 3461 +++++++++++++++++++++++++
 xen/include/xen/compiler.h            |   16 +
 xen/include/xen/device_tree.h         |   12 +
 8 files changed, 3535 insertions(+)
 create mode 100644 xen/drivers/passthrough/arm/smmu-v3.c

-- 
2.17.1



^ permalink raw reply	[flat|nested] 24+ messages in thread

* [PATCH v5 01/10] xen/arm: smmuv3: Import the SMMUv3 driver from Linux
  2021-01-20 14:52 [PATCH v5 00/10] xen/arm: Add support for SMMUv3 driver Rahul Singh
@ 2021-01-20 14:52 ` Rahul Singh
  2021-01-20 14:52 ` [PATCH v5 02/10] xen/arm: Revert atomic operation related command-queue insertion patch Rahul Singh
                   ` (8 subsequent siblings)
  9 siblings, 0 replies; 24+ messages in thread
From: Rahul Singh @ 2021-01-20 14:52 UTC (permalink / raw)
  To: xen-devel
  Cc: bertrand.marquis, rahul.singh, Stefano Stabellini, Julien Grall,
	Volodymyr Babchuk

Based on tag Linux 5.8.18 commit ab435ce49bd1d02e33dfec24f76955dc1196970b

Directory structure change for the SMMUv3 driver starting from
Linux 5.9, to revert the patches smoothly using the "git revert" command
we decided to choose Linux 5.8.18.

Only difference between latest stable Linux 5.9.12 and Linux 5.8.18
SMMUv3 driver is the use of the "fallthrough" keyword. This patch will
be merged once "fallthrough" keyword implementation is available in XEN.

It's a copy of the Linux SMMUv3 driver. Xen specific code has not
been added yet and code has not been compiled.

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
Changes since v2:
- Import the driver from Linux 5.8.18 as compared to the previous
  version where Linux 5.9.8 is used. Linux 5.8.18 has been chosen to
  smoothly revert the changes required as directory structure changes
  for the SMMUv3 driver starting from 5.9. The only difference between
  Linux 5.8.18 and Linux 5.9.8 is the use of fallthrough keyword.
Changes since v3: No changes
Changes since v4: No changes
---
---
 xen/drivers/passthrough/arm/smmu-v3.c | 4165 +++++++++++++++++++++++++
 1 file changed, 4165 insertions(+)
 create mode 100644 xen/drivers/passthrough/arm/smmu-v3.c

diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
new file mode 100644
index 0000000000..f578677a5c
--- /dev/null
+++ b/xen/drivers/passthrough/arm/smmu-v3.c
@@ -0,0 +1,4165 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * IOMMU API for ARM architected SMMUv3 implementations.
+ *
+ * Copyright (C) 2015 ARM Limited
+ *
+ * Author: Will Deacon <will.deacon@arm.com>
+ *
+ * This driver is powered by bad coffee and bombay mix.
+ */
+
+#include <linux/acpi.h>
+#include <linux/acpi_iort.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/crash_dump.h>
+#include <linux/delay.h>
+#include <linux/dma-iommu.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io-pgtable.h>
+#include <linux/iommu.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_iommu.h>
+#include <linux/of_platform.h>
+#include <linux/pci.h>
+#include <linux/pci-ats.h>
+#include <linux/platform_device.h>
+
+#include <linux/amba/bus.h>
+
+/* MMIO registers */
+#define ARM_SMMU_IDR0			0x0
+#define IDR0_ST_LVL			GENMASK(28, 27)
+#define IDR0_ST_LVL_2LVL		1
+#define IDR0_STALL_MODEL		GENMASK(25, 24)
+#define IDR0_STALL_MODEL_STALL		0
+#define IDR0_STALL_MODEL_FORCE		2
+#define IDR0_TTENDIAN			GENMASK(22, 21)
+#define IDR0_TTENDIAN_MIXED		0
+#define IDR0_TTENDIAN_LE		2
+#define IDR0_TTENDIAN_BE		3
+#define IDR0_CD2L			(1 << 19)
+#define IDR0_VMID16			(1 << 18)
+#define IDR0_PRI			(1 << 16)
+#define IDR0_SEV			(1 << 14)
+#define IDR0_MSI			(1 << 13)
+#define IDR0_ASID16			(1 << 12)
+#define IDR0_ATS			(1 << 10)
+#define IDR0_HYP			(1 << 9)
+#define IDR0_COHACC			(1 << 4)
+#define IDR0_TTF			GENMASK(3, 2)
+#define IDR0_TTF_AARCH64		2
+#define IDR0_TTF_AARCH32_64		3
+#define IDR0_S1P			(1 << 1)
+#define IDR0_S2P			(1 << 0)
+
+#define ARM_SMMU_IDR1			0x4
+#define IDR1_TABLES_PRESET		(1 << 30)
+#define IDR1_QUEUES_PRESET		(1 << 29)
+#define IDR1_REL			(1 << 28)
+#define IDR1_CMDQS			GENMASK(25, 21)
+#define IDR1_EVTQS			GENMASK(20, 16)
+#define IDR1_PRIQS			GENMASK(15, 11)
+#define IDR1_SSIDSIZE			GENMASK(10, 6)
+#define IDR1_SIDSIZE			GENMASK(5, 0)
+
+#define ARM_SMMU_IDR3			0xc
+#define IDR3_RIL			(1 << 10)
+
+#define ARM_SMMU_IDR5			0x14
+#define IDR5_STALL_MAX			GENMASK(31, 16)
+#define IDR5_GRAN64K			(1 << 6)
+#define IDR5_GRAN16K			(1 << 5)
+#define IDR5_GRAN4K			(1 << 4)
+#define IDR5_OAS			GENMASK(2, 0)
+#define IDR5_OAS_32_BIT			0
+#define IDR5_OAS_36_BIT			1
+#define IDR5_OAS_40_BIT			2
+#define IDR5_OAS_42_BIT			3
+#define IDR5_OAS_44_BIT			4
+#define IDR5_OAS_48_BIT			5
+#define IDR5_OAS_52_BIT			6
+#define IDR5_VAX			GENMASK(11, 10)
+#define IDR5_VAX_52_BIT			1
+
+#define ARM_SMMU_CR0			0x20
+#define CR0_ATSCHK			(1 << 4)
+#define CR0_CMDQEN			(1 << 3)
+#define CR0_EVTQEN			(1 << 2)
+#define CR0_PRIQEN			(1 << 1)
+#define CR0_SMMUEN			(1 << 0)
+
+#define ARM_SMMU_CR0ACK			0x24
+
+#define ARM_SMMU_CR1			0x28
+#define CR1_TABLE_SH			GENMASK(11, 10)
+#define CR1_TABLE_OC			GENMASK(9, 8)
+#define CR1_TABLE_IC			GENMASK(7, 6)
+#define CR1_QUEUE_SH			GENMASK(5, 4)
+#define CR1_QUEUE_OC			GENMASK(3, 2)
+#define CR1_QUEUE_IC			GENMASK(1, 0)
+/* CR1 cacheability fields don't quite follow the usual TCR-style encoding */
+#define CR1_CACHE_NC			0
+#define CR1_CACHE_WB			1
+#define CR1_CACHE_WT			2
+
+#define ARM_SMMU_CR2			0x2c
+#define CR2_PTM				(1 << 2)
+#define CR2_RECINVSID			(1 << 1)
+#define CR2_E2H				(1 << 0)
+
+#define ARM_SMMU_GBPA			0x44
+#define GBPA_UPDATE			(1 << 31)
+#define GBPA_ABORT			(1 << 20)
+
+#define ARM_SMMU_IRQ_CTRL		0x50
+#define IRQ_CTRL_EVTQ_IRQEN		(1 << 2)
+#define IRQ_CTRL_PRIQ_IRQEN		(1 << 1)
+#define IRQ_CTRL_GERROR_IRQEN		(1 << 0)
+
+#define ARM_SMMU_IRQ_CTRLACK		0x54
+
+#define ARM_SMMU_GERROR			0x60
+#define GERROR_SFM_ERR			(1 << 8)
+#define GERROR_MSI_GERROR_ABT_ERR	(1 << 7)
+#define GERROR_MSI_PRIQ_ABT_ERR		(1 << 6)
+#define GERROR_MSI_EVTQ_ABT_ERR		(1 << 5)
+#define GERROR_MSI_CMDQ_ABT_ERR		(1 << 4)
+#define GERROR_PRIQ_ABT_ERR		(1 << 3)
+#define GERROR_EVTQ_ABT_ERR		(1 << 2)
+#define GERROR_CMDQ_ERR			(1 << 0)
+#define GERROR_ERR_MASK			0xfd
+
+#define ARM_SMMU_GERRORN		0x64
+
+#define ARM_SMMU_GERROR_IRQ_CFG0	0x68
+#define ARM_SMMU_GERROR_IRQ_CFG1	0x70
+#define ARM_SMMU_GERROR_IRQ_CFG2	0x74
+
+#define ARM_SMMU_STRTAB_BASE		0x80
+#define STRTAB_BASE_RA			(1UL << 62)
+#define STRTAB_BASE_ADDR_MASK		GENMASK_ULL(51, 6)
+
+#define ARM_SMMU_STRTAB_BASE_CFG	0x88
+#define STRTAB_BASE_CFG_FMT		GENMASK(17, 16)
+#define STRTAB_BASE_CFG_FMT_LINEAR	0
+#define STRTAB_BASE_CFG_FMT_2LVL	1
+#define STRTAB_BASE_CFG_SPLIT		GENMASK(10, 6)
+#define STRTAB_BASE_CFG_LOG2SIZE	GENMASK(5, 0)
+
+#define ARM_SMMU_CMDQ_BASE		0x90
+#define ARM_SMMU_CMDQ_PROD		0x98
+#define ARM_SMMU_CMDQ_CONS		0x9c
+
+#define ARM_SMMU_EVTQ_BASE		0xa0
+#define ARM_SMMU_EVTQ_PROD		0x100a8
+#define ARM_SMMU_EVTQ_CONS		0x100ac
+#define ARM_SMMU_EVTQ_IRQ_CFG0		0xb0
+#define ARM_SMMU_EVTQ_IRQ_CFG1		0xb8
+#define ARM_SMMU_EVTQ_IRQ_CFG2		0xbc
+
+#define ARM_SMMU_PRIQ_BASE		0xc0
+#define ARM_SMMU_PRIQ_PROD		0x100c8
+#define ARM_SMMU_PRIQ_CONS		0x100cc
+#define ARM_SMMU_PRIQ_IRQ_CFG0		0xd0
+#define ARM_SMMU_PRIQ_IRQ_CFG1		0xd8
+#define ARM_SMMU_PRIQ_IRQ_CFG2		0xdc
+
+#define ARM_SMMU_REG_SZ			0xe00
+
+/* Common MSI config fields */
+#define MSI_CFG0_ADDR_MASK		GENMASK_ULL(51, 2)
+#define MSI_CFG2_SH			GENMASK(5, 4)
+#define MSI_CFG2_MEMATTR		GENMASK(3, 0)
+
+/* Common memory attribute values */
+#define ARM_SMMU_SH_NSH			0
+#define ARM_SMMU_SH_OSH			2
+#define ARM_SMMU_SH_ISH			3
+#define ARM_SMMU_MEMATTR_DEVICE_nGnRE	0x1
+#define ARM_SMMU_MEMATTR_OIWB		0xf
+
+#define Q_IDX(llq, p)			((p) & ((1 << (llq)->max_n_shift) - 1))
+#define Q_WRP(llq, p)			((p) & (1 << (llq)->max_n_shift))
+#define Q_OVERFLOW_FLAG			(1U << 31)
+#define Q_OVF(p)			((p) & Q_OVERFLOW_FLAG)
+#define Q_ENT(q, p)			((q)->base +			\
+					 Q_IDX(&((q)->llq), p) *	\
+					 (q)->ent_dwords)
+
+#define Q_BASE_RWA			(1UL << 62)
+#define Q_BASE_ADDR_MASK		GENMASK_ULL(51, 5)
+#define Q_BASE_LOG2SIZE			GENMASK(4, 0)
+
+/* Ensure DMA allocations are naturally aligned */
+#ifdef CONFIG_CMA_ALIGNMENT
+#define Q_MAX_SZ_SHIFT			(PAGE_SHIFT + CONFIG_CMA_ALIGNMENT)
+#else
+#define Q_MAX_SZ_SHIFT			(PAGE_SHIFT + MAX_ORDER - 1)
+#endif
+
+/*
+ * Stream table.
+ *
+ * Linear: Enough to cover 1 << IDR1.SIDSIZE entries
+ * 2lvl: 128k L1 entries,
+ *       256 lazy entries per table (each table covers a PCI bus)
+ */
+#define STRTAB_L1_SZ_SHIFT		20
+#define STRTAB_SPLIT			8
+
+#define STRTAB_L1_DESC_DWORDS		1
+#define STRTAB_L1_DESC_SPAN		GENMASK_ULL(4, 0)
+#define STRTAB_L1_DESC_L2PTR_MASK	GENMASK_ULL(51, 6)
+
+#define STRTAB_STE_DWORDS		8
+#define STRTAB_STE_0_V			(1UL << 0)
+#define STRTAB_STE_0_CFG		GENMASK_ULL(3, 1)
+#define STRTAB_STE_0_CFG_ABORT		0
+#define STRTAB_STE_0_CFG_BYPASS		4
+#define STRTAB_STE_0_CFG_S1_TRANS	5
+#define STRTAB_STE_0_CFG_S2_TRANS	6
+
+#define STRTAB_STE_0_S1FMT		GENMASK_ULL(5, 4)
+#define STRTAB_STE_0_S1FMT_LINEAR	0
+#define STRTAB_STE_0_S1FMT_64K_L2	2
+#define STRTAB_STE_0_S1CTXPTR_MASK	GENMASK_ULL(51, 6)
+#define STRTAB_STE_0_S1CDMAX		GENMASK_ULL(63, 59)
+
+#define STRTAB_STE_1_S1DSS		GENMASK_ULL(1, 0)
+#define STRTAB_STE_1_S1DSS_TERMINATE	0x0
+#define STRTAB_STE_1_S1DSS_BYPASS	0x1
+#define STRTAB_STE_1_S1DSS_SSID0	0x2
+
+#define STRTAB_STE_1_S1C_CACHE_NC	0UL
+#define STRTAB_STE_1_S1C_CACHE_WBRA	1UL
+#define STRTAB_STE_1_S1C_CACHE_WT	2UL
+#define STRTAB_STE_1_S1C_CACHE_WB	3UL
+#define STRTAB_STE_1_S1CIR		GENMASK_ULL(3, 2)
+#define STRTAB_STE_1_S1COR		GENMASK_ULL(5, 4)
+#define STRTAB_STE_1_S1CSH		GENMASK_ULL(7, 6)
+
+#define STRTAB_STE_1_S1STALLD		(1UL << 27)
+
+#define STRTAB_STE_1_EATS		GENMASK_ULL(29, 28)
+#define STRTAB_STE_1_EATS_ABT		0UL
+#define STRTAB_STE_1_EATS_TRANS		1UL
+#define STRTAB_STE_1_EATS_S1CHK		2UL
+
+#define STRTAB_STE_1_STRW		GENMASK_ULL(31, 30)
+#define STRTAB_STE_1_STRW_NSEL1		0UL
+#define STRTAB_STE_1_STRW_EL2		2UL
+
+#define STRTAB_STE_1_SHCFG		GENMASK_ULL(45, 44)
+#define STRTAB_STE_1_SHCFG_INCOMING	1UL
+
+#define STRTAB_STE_2_S2VMID		GENMASK_ULL(15, 0)
+#define STRTAB_STE_2_VTCR		GENMASK_ULL(50, 32)
+#define STRTAB_STE_2_VTCR_S2T0SZ	GENMASK_ULL(5, 0)
+#define STRTAB_STE_2_VTCR_S2SL0		GENMASK_ULL(7, 6)
+#define STRTAB_STE_2_VTCR_S2IR0		GENMASK_ULL(9, 8)
+#define STRTAB_STE_2_VTCR_S2OR0		GENMASK_ULL(11, 10)
+#define STRTAB_STE_2_VTCR_S2SH0		GENMASK_ULL(13, 12)
+#define STRTAB_STE_2_VTCR_S2TG		GENMASK_ULL(15, 14)
+#define STRTAB_STE_2_VTCR_S2PS		GENMASK_ULL(18, 16)
+#define STRTAB_STE_2_S2AA64		(1UL << 51)
+#define STRTAB_STE_2_S2ENDI		(1UL << 52)
+#define STRTAB_STE_2_S2PTW		(1UL << 54)
+#define STRTAB_STE_2_S2R		(1UL << 58)
+
+#define STRTAB_STE_3_S2TTB_MASK		GENMASK_ULL(51, 4)
+
+/*
+ * Context descriptors.
+ *
+ * Linear: when less than 1024 SSIDs are supported
+ * 2lvl: at most 1024 L1 entries,
+ *       1024 lazy entries per table.
+ */
+#define CTXDESC_SPLIT			10
+#define CTXDESC_L2_ENTRIES		(1 << CTXDESC_SPLIT)
+
+#define CTXDESC_L1_DESC_DWORDS		1
+#define CTXDESC_L1_DESC_V		(1UL << 0)
+#define CTXDESC_L1_DESC_L2PTR_MASK	GENMASK_ULL(51, 12)
+
+#define CTXDESC_CD_DWORDS		8
+#define CTXDESC_CD_0_TCR_T0SZ		GENMASK_ULL(5, 0)
+#define CTXDESC_CD_0_TCR_TG0		GENMASK_ULL(7, 6)
+#define CTXDESC_CD_0_TCR_IRGN0		GENMASK_ULL(9, 8)
+#define CTXDESC_CD_0_TCR_ORGN0		GENMASK_ULL(11, 10)
+#define CTXDESC_CD_0_TCR_SH0		GENMASK_ULL(13, 12)
+#define CTXDESC_CD_0_TCR_EPD0		(1ULL << 14)
+#define CTXDESC_CD_0_TCR_EPD1		(1ULL << 30)
+
+#define CTXDESC_CD_0_ENDI		(1UL << 15)
+#define CTXDESC_CD_0_V			(1UL << 31)
+
+#define CTXDESC_CD_0_TCR_IPS		GENMASK_ULL(34, 32)
+#define CTXDESC_CD_0_TCR_TBI0		(1ULL << 38)
+
+#define CTXDESC_CD_0_AA64		(1UL << 41)
+#define CTXDESC_CD_0_S			(1UL << 44)
+#define CTXDESC_CD_0_R			(1UL << 45)
+#define CTXDESC_CD_0_A			(1UL << 46)
+#define CTXDESC_CD_0_ASET		(1UL << 47)
+#define CTXDESC_CD_0_ASID		GENMASK_ULL(63, 48)
+
+#define CTXDESC_CD_1_TTB0_MASK		GENMASK_ULL(51, 4)
+
+/*
+ * When the SMMU only supports linear context descriptor tables, pick a
+ * reasonable size limit (64kB).
+ */
+#define CTXDESC_LINEAR_CDMAX		ilog2(SZ_64K / (CTXDESC_CD_DWORDS << 3))
+
+/* Command queue */
+#define CMDQ_ENT_SZ_SHIFT		4
+#define CMDQ_ENT_DWORDS			((1 << CMDQ_ENT_SZ_SHIFT) >> 3)
+#define CMDQ_MAX_SZ_SHIFT		(Q_MAX_SZ_SHIFT - CMDQ_ENT_SZ_SHIFT)
+
+#define CMDQ_CONS_ERR			GENMASK(30, 24)
+#define CMDQ_ERR_CERROR_NONE_IDX	0
+#define CMDQ_ERR_CERROR_ILL_IDX		1
+#define CMDQ_ERR_CERROR_ABT_IDX		2
+#define CMDQ_ERR_CERROR_ATC_INV_IDX	3
+
+#define CMDQ_PROD_OWNED_FLAG		Q_OVERFLOW_FLAG
+
+/*
+ * This is used to size the command queue and therefore must be at least
+ * BITS_PER_LONG so that the valid_map works correctly (it relies on the
+ * total number of queue entries being a multiple of BITS_PER_LONG).
+ */
+#define CMDQ_BATCH_ENTRIES		BITS_PER_LONG
+
+#define CMDQ_0_OP			GENMASK_ULL(7, 0)
+#define CMDQ_0_SSV			(1UL << 11)
+
+#define CMDQ_PREFETCH_0_SID		GENMASK_ULL(63, 32)
+#define CMDQ_PREFETCH_1_SIZE		GENMASK_ULL(4, 0)
+#define CMDQ_PREFETCH_1_ADDR_MASK	GENMASK_ULL(63, 12)
+
+#define CMDQ_CFGI_0_SSID		GENMASK_ULL(31, 12)
+#define CMDQ_CFGI_0_SID			GENMASK_ULL(63, 32)
+#define CMDQ_CFGI_1_LEAF		(1UL << 0)
+#define CMDQ_CFGI_1_RANGE		GENMASK_ULL(4, 0)
+
+#define CMDQ_TLBI_0_NUM			GENMASK_ULL(16, 12)
+#define CMDQ_TLBI_RANGE_NUM_MAX		31
+#define CMDQ_TLBI_0_SCALE		GENMASK_ULL(24, 20)
+#define CMDQ_TLBI_0_VMID		GENMASK_ULL(47, 32)
+#define CMDQ_TLBI_0_ASID		GENMASK_ULL(63, 48)
+#define CMDQ_TLBI_1_LEAF		(1UL << 0)
+#define CMDQ_TLBI_1_TTL			GENMASK_ULL(9, 8)
+#define CMDQ_TLBI_1_TG			GENMASK_ULL(11, 10)
+#define CMDQ_TLBI_1_VA_MASK		GENMASK_ULL(63, 12)
+#define CMDQ_TLBI_1_IPA_MASK		GENMASK_ULL(51, 12)
+
+#define CMDQ_ATC_0_SSID			GENMASK_ULL(31, 12)
+#define CMDQ_ATC_0_SID			GENMASK_ULL(63, 32)
+#define CMDQ_ATC_0_GLOBAL		(1UL << 9)
+#define CMDQ_ATC_1_SIZE			GENMASK_ULL(5, 0)
+#define CMDQ_ATC_1_ADDR_MASK		GENMASK_ULL(63, 12)
+
+#define CMDQ_PRI_0_SSID			GENMASK_ULL(31, 12)
+#define CMDQ_PRI_0_SID			GENMASK_ULL(63, 32)
+#define CMDQ_PRI_1_GRPID		GENMASK_ULL(8, 0)
+#define CMDQ_PRI_1_RESP			GENMASK_ULL(13, 12)
+
+#define CMDQ_SYNC_0_CS			GENMASK_ULL(13, 12)
+#define CMDQ_SYNC_0_CS_NONE		0
+#define CMDQ_SYNC_0_CS_IRQ		1
+#define CMDQ_SYNC_0_CS_SEV		2
+#define CMDQ_SYNC_0_MSH			GENMASK_ULL(23, 22)
+#define CMDQ_SYNC_0_MSIATTR		GENMASK_ULL(27, 24)
+#define CMDQ_SYNC_0_MSIDATA		GENMASK_ULL(63, 32)
+#define CMDQ_SYNC_1_MSIADDR_MASK	GENMASK_ULL(51, 2)
+
+/* Event queue */
+#define EVTQ_ENT_SZ_SHIFT		5
+#define EVTQ_ENT_DWORDS			((1 << EVTQ_ENT_SZ_SHIFT) >> 3)
+#define EVTQ_MAX_SZ_SHIFT		(Q_MAX_SZ_SHIFT - EVTQ_ENT_SZ_SHIFT)
+
+#define EVTQ_0_ID			GENMASK_ULL(7, 0)
+
+/* PRI queue */
+#define PRIQ_ENT_SZ_SHIFT		4
+#define PRIQ_ENT_DWORDS			((1 << PRIQ_ENT_SZ_SHIFT) >> 3)
+#define PRIQ_MAX_SZ_SHIFT		(Q_MAX_SZ_SHIFT - PRIQ_ENT_SZ_SHIFT)
+
+#define PRIQ_0_SID			GENMASK_ULL(31, 0)
+#define PRIQ_0_SSID			GENMASK_ULL(51, 32)
+#define PRIQ_0_PERM_PRIV		(1UL << 58)
+#define PRIQ_0_PERM_EXEC		(1UL << 59)
+#define PRIQ_0_PERM_READ		(1UL << 60)
+#define PRIQ_0_PERM_WRITE		(1UL << 61)
+#define PRIQ_0_PRG_LAST			(1UL << 62)
+#define PRIQ_0_SSID_V			(1UL << 63)
+
+#define PRIQ_1_PRG_IDX			GENMASK_ULL(8, 0)
+#define PRIQ_1_ADDR_MASK		GENMASK_ULL(63, 12)
+
+/* High-level queue structures */
+#define ARM_SMMU_POLL_TIMEOUT_US	1000000 /* 1s! */
+#define ARM_SMMU_POLL_SPIN_COUNT	10
+
+#define MSI_IOVA_BASE			0x8000000
+#define MSI_IOVA_LENGTH			0x100000
+
+static bool disable_bypass = 1;
+module_param_named(disable_bypass, disable_bypass, bool, S_IRUGO);
+MODULE_PARM_DESC(disable_bypass,
+	"Disable bypass streams such that incoming transactions from devices that are not attached to an iommu domain will report an abort back to the device and will not be allowed to pass through the SMMU.");
+
+enum pri_resp {
+	PRI_RESP_DENY = 0,
+	PRI_RESP_FAIL = 1,
+	PRI_RESP_SUCC = 2,
+};
+
+enum arm_smmu_msi_index {
+	EVTQ_MSI_INDEX,
+	GERROR_MSI_INDEX,
+	PRIQ_MSI_INDEX,
+	ARM_SMMU_MAX_MSIS,
+};
+
+static phys_addr_t arm_smmu_msi_cfg[ARM_SMMU_MAX_MSIS][3] = {
+	[EVTQ_MSI_INDEX] = {
+		ARM_SMMU_EVTQ_IRQ_CFG0,
+		ARM_SMMU_EVTQ_IRQ_CFG1,
+		ARM_SMMU_EVTQ_IRQ_CFG2,
+	},
+	[GERROR_MSI_INDEX] = {
+		ARM_SMMU_GERROR_IRQ_CFG0,
+		ARM_SMMU_GERROR_IRQ_CFG1,
+		ARM_SMMU_GERROR_IRQ_CFG2,
+	},
+	[PRIQ_MSI_INDEX] = {
+		ARM_SMMU_PRIQ_IRQ_CFG0,
+		ARM_SMMU_PRIQ_IRQ_CFG1,
+		ARM_SMMU_PRIQ_IRQ_CFG2,
+	},
+};
+
+struct arm_smmu_cmdq_ent {
+	/* Common fields */
+	u8				opcode;
+	bool				substream_valid;
+
+	/* Command-specific fields */
+	union {
+		#define CMDQ_OP_PREFETCH_CFG	0x1
+		struct {
+			u32			sid;
+			u8			size;
+			u64			addr;
+		} prefetch;
+
+		#define CMDQ_OP_CFGI_STE	0x3
+		#define CMDQ_OP_CFGI_ALL	0x4
+		#define CMDQ_OP_CFGI_CD		0x5
+		#define CMDQ_OP_CFGI_CD_ALL	0x6
+		struct {
+			u32			sid;
+			u32			ssid;
+			union {
+				bool		leaf;
+				u8		span;
+			};
+		} cfgi;
+
+		#define CMDQ_OP_TLBI_NH_ASID	0x11
+		#define CMDQ_OP_TLBI_NH_VA	0x12
+		#define CMDQ_OP_TLBI_EL2_ALL	0x20
+		#define CMDQ_OP_TLBI_S12_VMALL	0x28
+		#define CMDQ_OP_TLBI_S2_IPA	0x2a
+		#define CMDQ_OP_TLBI_NSNH_ALL	0x30
+		struct {
+			u8			num;
+			u8			scale;
+			u16			asid;
+			u16			vmid;
+			bool			leaf;
+			u8			ttl;
+			u8			tg;
+			u64			addr;
+		} tlbi;
+
+		#define CMDQ_OP_ATC_INV		0x40
+		#define ATC_INV_SIZE_ALL	52
+		struct {
+			u32			sid;
+			u32			ssid;
+			u64			addr;
+			u8			size;
+			bool			global;
+		} atc;
+
+		#define CMDQ_OP_PRI_RESP	0x41
+		struct {
+			u32			sid;
+			u32			ssid;
+			u16			grpid;
+			enum pri_resp		resp;
+		} pri;
+
+		#define CMDQ_OP_CMD_SYNC	0x46
+		struct {
+			u64			msiaddr;
+		} sync;
+	};
+};
+
+struct arm_smmu_ll_queue {
+	union {
+		u64			val;
+		struct {
+			u32		prod;
+			u32		cons;
+		};
+		struct {
+			atomic_t	prod;
+			atomic_t	cons;
+		} atomic;
+		u8			__pad[SMP_CACHE_BYTES];
+	} ____cacheline_aligned_in_smp;
+	u32				max_n_shift;
+};
+
+struct arm_smmu_queue {
+	struct arm_smmu_ll_queue	llq;
+	int				irq; /* Wired interrupt */
+
+	__le64				*base;
+	dma_addr_t			base_dma;
+	u64				q_base;
+
+	size_t				ent_dwords;
+
+	u32 __iomem			*prod_reg;
+	u32 __iomem			*cons_reg;
+};
+
+struct arm_smmu_queue_poll {
+	ktime_t				timeout;
+	unsigned int			delay;
+	unsigned int			spin_cnt;
+	bool				wfe;
+};
+
+struct arm_smmu_cmdq {
+	struct arm_smmu_queue		q;
+	atomic_long_t			*valid_map;
+	atomic_t			owner_prod;
+	atomic_t			lock;
+};
+
+struct arm_smmu_cmdq_batch {
+	u64				cmds[CMDQ_BATCH_ENTRIES * CMDQ_ENT_DWORDS];
+	int				num;
+};
+
+struct arm_smmu_evtq {
+	struct arm_smmu_queue		q;
+	u32				max_stalls;
+};
+
+struct arm_smmu_priq {
+	struct arm_smmu_queue		q;
+};
+
+/* High-level stream table and context descriptor structures */
+struct arm_smmu_strtab_l1_desc {
+	u8				span;
+
+	__le64				*l2ptr;
+	dma_addr_t			l2ptr_dma;
+};
+
+struct arm_smmu_ctx_desc {
+	u16				asid;
+	u64				ttbr;
+	u64				tcr;
+	u64				mair;
+};
+
+struct arm_smmu_l1_ctx_desc {
+	__le64				*l2ptr;
+	dma_addr_t			l2ptr_dma;
+};
+
+struct arm_smmu_ctx_desc_cfg {
+	__le64				*cdtab;
+	dma_addr_t			cdtab_dma;
+	struct arm_smmu_l1_ctx_desc	*l1_desc;
+	unsigned int			num_l1_ents;
+};
+
+struct arm_smmu_s1_cfg {
+	struct arm_smmu_ctx_desc_cfg	cdcfg;
+	struct arm_smmu_ctx_desc	cd;
+	u8				s1fmt;
+	u8				s1cdmax;
+};
+
+struct arm_smmu_s2_cfg {
+	u16				vmid;
+	u64				vttbr;
+	u64				vtcr;
+};
+
+struct arm_smmu_strtab_cfg {
+	__le64				*strtab;
+	dma_addr_t			strtab_dma;
+	struct arm_smmu_strtab_l1_desc	*l1_desc;
+	unsigned int			num_l1_ents;
+
+	u64				strtab_base;
+	u32				strtab_base_cfg;
+};
+
+/* An SMMUv3 instance */
+struct arm_smmu_device {
+	struct device			*dev;
+	void __iomem			*base;
+	void __iomem			*page1;
+
+#define ARM_SMMU_FEAT_2_LVL_STRTAB	(1 << 0)
+#define ARM_SMMU_FEAT_2_LVL_CDTAB	(1 << 1)
+#define ARM_SMMU_FEAT_TT_LE		(1 << 2)
+#define ARM_SMMU_FEAT_TT_BE		(1 << 3)
+#define ARM_SMMU_FEAT_PRI		(1 << 4)
+#define ARM_SMMU_FEAT_ATS		(1 << 5)
+#define ARM_SMMU_FEAT_SEV		(1 << 6)
+#define ARM_SMMU_FEAT_MSI		(1 << 7)
+#define ARM_SMMU_FEAT_COHERENCY		(1 << 8)
+#define ARM_SMMU_FEAT_TRANS_S1		(1 << 9)
+#define ARM_SMMU_FEAT_TRANS_S2		(1 << 10)
+#define ARM_SMMU_FEAT_STALLS		(1 << 11)
+#define ARM_SMMU_FEAT_HYP		(1 << 12)
+#define ARM_SMMU_FEAT_STALL_FORCE	(1 << 13)
+#define ARM_SMMU_FEAT_VAX		(1 << 14)
+#define ARM_SMMU_FEAT_RANGE_INV		(1 << 15)
+	u32				features;
+
+#define ARM_SMMU_OPT_SKIP_PREFETCH	(1 << 0)
+#define ARM_SMMU_OPT_PAGE0_REGS_ONLY	(1 << 1)
+	u32				options;
+
+	struct arm_smmu_cmdq		cmdq;
+	struct arm_smmu_evtq		evtq;
+	struct arm_smmu_priq		priq;
+
+	int				gerr_irq;
+	int				combined_irq;
+
+	unsigned long			ias; /* IPA */
+	unsigned long			oas; /* PA */
+	unsigned long			pgsize_bitmap;
+
+#define ARM_SMMU_MAX_ASIDS		(1 << 16)
+	unsigned int			asid_bits;
+
+#define ARM_SMMU_MAX_VMIDS		(1 << 16)
+	unsigned int			vmid_bits;
+	DECLARE_BITMAP(vmid_map, ARM_SMMU_MAX_VMIDS);
+
+	unsigned int			ssid_bits;
+	unsigned int			sid_bits;
+
+	struct arm_smmu_strtab_cfg	strtab_cfg;
+
+	/* IOMMU core code handle */
+	struct iommu_device		iommu;
+};
+
+/* SMMU private data for each master */
+struct arm_smmu_master {
+	struct arm_smmu_device		*smmu;
+	struct device			*dev;
+	struct arm_smmu_domain		*domain;
+	struct list_head		domain_head;
+	u32				*sids;
+	unsigned int			num_sids;
+	bool				ats_enabled;
+	unsigned int			ssid_bits;
+};
+
+/* SMMU private data for an IOMMU domain */
+enum arm_smmu_domain_stage {
+	ARM_SMMU_DOMAIN_S1 = 0,
+	ARM_SMMU_DOMAIN_S2,
+	ARM_SMMU_DOMAIN_NESTED,
+	ARM_SMMU_DOMAIN_BYPASS,
+};
+
+struct arm_smmu_domain {
+	struct arm_smmu_device		*smmu;
+	struct mutex			init_mutex; /* Protects smmu pointer */
+
+	struct io_pgtable_ops		*pgtbl_ops;
+	bool				non_strict;
+	atomic_t			nr_ats_masters;
+
+	enum arm_smmu_domain_stage	stage;
+	union {
+		struct arm_smmu_s1_cfg	s1_cfg;
+		struct arm_smmu_s2_cfg	s2_cfg;
+	};
+
+	struct iommu_domain		domain;
+
+	struct list_head		devices;
+	spinlock_t			devices_lock;
+};
+
+struct arm_smmu_option_prop {
+	u32 opt;
+	const char *prop;
+};
+
+static DEFINE_XARRAY_ALLOC1(asid_xa);
+
+static struct arm_smmu_option_prop arm_smmu_options[] = {
+	{ ARM_SMMU_OPT_SKIP_PREFETCH, "hisilicon,broken-prefetch-cmd" },
+	{ ARM_SMMU_OPT_PAGE0_REGS_ONLY, "cavium,cn9900-broken-page1-regspace"},
+	{ 0, NULL},
+};
+
+static inline void __iomem *arm_smmu_page1_fixup(unsigned long offset,
+						 struct arm_smmu_device *smmu)
+{
+	if (offset > SZ_64K)
+		return smmu->page1 + offset - SZ_64K;
+
+	return smmu->base + offset;
+}
+
+static struct arm_smmu_domain *to_smmu_domain(struct iommu_domain *dom)
+{
+	return container_of(dom, struct arm_smmu_domain, domain);
+}
+
+static void parse_driver_options(struct arm_smmu_device *smmu)
+{
+	int i = 0;
+
+	do {
+		if (of_property_read_bool(smmu->dev->of_node,
+						arm_smmu_options[i].prop)) {
+			smmu->options |= arm_smmu_options[i].opt;
+			dev_notice(smmu->dev, "option %s\n",
+				arm_smmu_options[i].prop);
+		}
+	} while (arm_smmu_options[++i].opt);
+}
+
+/* Low-level queue manipulation functions */
+static bool queue_has_space(struct arm_smmu_ll_queue *q, u32 n)
+{
+	u32 space, prod, cons;
+
+	prod = Q_IDX(q, q->prod);
+	cons = Q_IDX(q, q->cons);
+
+	if (Q_WRP(q, q->prod) == Q_WRP(q, q->cons))
+		space = (1 << q->max_n_shift) - (prod - cons);
+	else
+		space = cons - prod;
+
+	return space >= n;
+}
+
+static bool queue_full(struct arm_smmu_ll_queue *q)
+{
+	return Q_IDX(q, q->prod) == Q_IDX(q, q->cons) &&
+	       Q_WRP(q, q->prod) != Q_WRP(q, q->cons);
+}
+
+static bool queue_empty(struct arm_smmu_ll_queue *q)
+{
+	return Q_IDX(q, q->prod) == Q_IDX(q, q->cons) &&
+	       Q_WRP(q, q->prod) == Q_WRP(q, q->cons);
+}
+
+static bool queue_consumed(struct arm_smmu_ll_queue *q, u32 prod)
+{
+	return ((Q_WRP(q, q->cons) == Q_WRP(q, prod)) &&
+		(Q_IDX(q, q->cons) > Q_IDX(q, prod))) ||
+	       ((Q_WRP(q, q->cons) != Q_WRP(q, prod)) &&
+		(Q_IDX(q, q->cons) <= Q_IDX(q, prod)));
+}
+
+static void queue_sync_cons_out(struct arm_smmu_queue *q)
+{
+	/*
+	 * Ensure that all CPU accesses (reads and writes) to the queue
+	 * are complete before we update the cons pointer.
+	 */
+	mb();
+	writel_relaxed(q->llq.cons, q->cons_reg);
+}
+
+static void queue_inc_cons(struct arm_smmu_ll_queue *q)
+{
+	u32 cons = (Q_WRP(q, q->cons) | Q_IDX(q, q->cons)) + 1;
+	q->cons = Q_OVF(q->cons) | Q_WRP(q, cons) | Q_IDX(q, cons);
+}
+
+static int queue_sync_prod_in(struct arm_smmu_queue *q)
+{
+	int ret = 0;
+	u32 prod = readl_relaxed(q->prod_reg);
+
+	if (Q_OVF(prod) != Q_OVF(q->llq.prod))
+		ret = -EOVERFLOW;
+
+	q->llq.prod = prod;
+	return ret;
+}
+
+static u32 queue_inc_prod_n(struct arm_smmu_ll_queue *q, int n)
+{
+	u32 prod = (Q_WRP(q, q->prod) | Q_IDX(q, q->prod)) + n;
+	return Q_OVF(q->prod) | Q_WRP(q, prod) | Q_IDX(q, prod);
+}
+
+static void queue_poll_init(struct arm_smmu_device *smmu,
+			    struct arm_smmu_queue_poll *qp)
+{
+	qp->delay = 1;
+	qp->spin_cnt = 0;
+	qp->wfe = !!(smmu->features & ARM_SMMU_FEAT_SEV);
+	qp->timeout = ktime_add_us(ktime_get(), ARM_SMMU_POLL_TIMEOUT_US);
+}
+
+static int queue_poll(struct arm_smmu_queue_poll *qp)
+{
+	if (ktime_compare(ktime_get(), qp->timeout) > 0)
+		return -ETIMEDOUT;
+
+	if (qp->wfe) {
+		wfe();
+	} else if (++qp->spin_cnt < ARM_SMMU_POLL_SPIN_COUNT) {
+		cpu_relax();
+	} else {
+		udelay(qp->delay);
+		qp->delay *= 2;
+		qp->spin_cnt = 0;
+	}
+
+	return 0;
+}
+
+static void queue_write(__le64 *dst, u64 *src, size_t n_dwords)
+{
+	int i;
+
+	for (i = 0; i < n_dwords; ++i)
+		*dst++ = cpu_to_le64(*src++);
+}
+
+static void queue_read(__le64 *dst, u64 *src, size_t n_dwords)
+{
+	int i;
+
+	for (i = 0; i < n_dwords; ++i)
+		*dst++ = le64_to_cpu(*src++);
+}
+
+static int queue_remove_raw(struct arm_smmu_queue *q, u64 *ent)
+{
+	if (queue_empty(&q->llq))
+		return -EAGAIN;
+
+	queue_read(ent, Q_ENT(q, q->llq.cons), q->ent_dwords);
+	queue_inc_cons(&q->llq);
+	queue_sync_cons_out(q);
+	return 0;
+}
+
+/* High-level queue accessors */
+static int arm_smmu_cmdq_build_cmd(u64 *cmd, struct arm_smmu_cmdq_ent *ent)
+{
+	memset(cmd, 0, 1 << CMDQ_ENT_SZ_SHIFT);
+	cmd[0] |= FIELD_PREP(CMDQ_0_OP, ent->opcode);
+
+	switch (ent->opcode) {
+	case CMDQ_OP_TLBI_EL2_ALL:
+	case CMDQ_OP_TLBI_NSNH_ALL:
+		break;
+	case CMDQ_OP_PREFETCH_CFG:
+		cmd[0] |= FIELD_PREP(CMDQ_PREFETCH_0_SID, ent->prefetch.sid);
+		cmd[1] |= FIELD_PREP(CMDQ_PREFETCH_1_SIZE, ent->prefetch.size);
+		cmd[1] |= ent->prefetch.addr & CMDQ_PREFETCH_1_ADDR_MASK;
+		break;
+	case CMDQ_OP_CFGI_CD:
+		cmd[0] |= FIELD_PREP(CMDQ_CFGI_0_SSID, ent->cfgi.ssid);
+		/* Fallthrough */
+	case CMDQ_OP_CFGI_STE:
+		cmd[0] |= FIELD_PREP(CMDQ_CFGI_0_SID, ent->cfgi.sid);
+		cmd[1] |= FIELD_PREP(CMDQ_CFGI_1_LEAF, ent->cfgi.leaf);
+		break;
+	case CMDQ_OP_CFGI_CD_ALL:
+		cmd[0] |= FIELD_PREP(CMDQ_CFGI_0_SID, ent->cfgi.sid);
+		break;
+	case CMDQ_OP_CFGI_ALL:
+		/* Cover the entire SID range */
+		cmd[1] |= FIELD_PREP(CMDQ_CFGI_1_RANGE, 31);
+		break;
+	case CMDQ_OP_TLBI_NH_VA:
+		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_NUM, ent->tlbi.num);
+		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_SCALE, ent->tlbi.scale);
+		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_VMID, ent->tlbi.vmid);
+		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_ASID, ent->tlbi.asid);
+		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_LEAF, ent->tlbi.leaf);
+		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_TTL, ent->tlbi.ttl);
+		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_TG, ent->tlbi.tg);
+		cmd[1] |= ent->tlbi.addr & CMDQ_TLBI_1_VA_MASK;
+		break;
+	case CMDQ_OP_TLBI_S2_IPA:
+		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_NUM, ent->tlbi.num);
+		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_SCALE, ent->tlbi.scale);
+		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_VMID, ent->tlbi.vmid);
+		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_LEAF, ent->tlbi.leaf);
+		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_TTL, ent->tlbi.ttl);
+		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_TG, ent->tlbi.tg);
+		cmd[1] |= ent->tlbi.addr & CMDQ_TLBI_1_IPA_MASK;
+		break;
+	case CMDQ_OP_TLBI_NH_ASID:
+		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_ASID, ent->tlbi.asid);
+		/* Fallthrough */
+	case CMDQ_OP_TLBI_S12_VMALL:
+		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_VMID, ent->tlbi.vmid);
+		break;
+	case CMDQ_OP_ATC_INV:
+		cmd[0] |= FIELD_PREP(CMDQ_0_SSV, ent->substream_valid);
+		cmd[0] |= FIELD_PREP(CMDQ_ATC_0_GLOBAL, ent->atc.global);
+		cmd[0] |= FIELD_PREP(CMDQ_ATC_0_SSID, ent->atc.ssid);
+		cmd[0] |= FIELD_PREP(CMDQ_ATC_0_SID, ent->atc.sid);
+		cmd[1] |= FIELD_PREP(CMDQ_ATC_1_SIZE, ent->atc.size);
+		cmd[1] |= ent->atc.addr & CMDQ_ATC_1_ADDR_MASK;
+		break;
+	case CMDQ_OP_PRI_RESP:
+		cmd[0] |= FIELD_PREP(CMDQ_0_SSV, ent->substream_valid);
+		cmd[0] |= FIELD_PREP(CMDQ_PRI_0_SSID, ent->pri.ssid);
+		cmd[0] |= FIELD_PREP(CMDQ_PRI_0_SID, ent->pri.sid);
+		cmd[1] |= FIELD_PREP(CMDQ_PRI_1_GRPID, ent->pri.grpid);
+		switch (ent->pri.resp) {
+		case PRI_RESP_DENY:
+		case PRI_RESP_FAIL:
+		case PRI_RESP_SUCC:
+			break;
+		default:
+			return -EINVAL;
+		}
+		cmd[1] |= FIELD_PREP(CMDQ_PRI_1_RESP, ent->pri.resp);
+		break;
+	case CMDQ_OP_CMD_SYNC:
+		if (ent->sync.msiaddr) {
+			cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_CS, CMDQ_SYNC_0_CS_IRQ);
+			cmd[1] |= ent->sync.msiaddr & CMDQ_SYNC_1_MSIADDR_MASK;
+		} else {
+			cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_CS, CMDQ_SYNC_0_CS_SEV);
+		}
+		cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_MSH, ARM_SMMU_SH_ISH);
+		cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_MSIATTR, ARM_SMMU_MEMATTR_OIWB);
+		break;
+	default:
+		return -ENOENT;
+	}
+
+	return 0;
+}
+
+static void arm_smmu_cmdq_build_sync_cmd(u64 *cmd, struct arm_smmu_device *smmu,
+					 u32 prod)
+{
+	struct arm_smmu_queue *q = &smmu->cmdq.q;
+	struct arm_smmu_cmdq_ent ent = {
+		.opcode = CMDQ_OP_CMD_SYNC,
+	};
+
+	/*
+	 * Beware that Hi16xx adds an extra 32 bits of goodness to its MSI
+	 * payload, so the write will zero the entire command on that platform.
+	 */
+	if (smmu->features & ARM_SMMU_FEAT_MSI &&
+	    smmu->features & ARM_SMMU_FEAT_COHERENCY) {
+		ent.sync.msiaddr = q->base_dma + Q_IDX(&q->llq, prod) *
+				   q->ent_dwords * 8;
+	}
+
+	arm_smmu_cmdq_build_cmd(cmd, &ent);
+}
+
+static void arm_smmu_cmdq_skip_err(struct arm_smmu_device *smmu)
+{
+	static const char *cerror_str[] = {
+		[CMDQ_ERR_CERROR_NONE_IDX]	= "No error",
+		[CMDQ_ERR_CERROR_ILL_IDX]	= "Illegal command",
+		[CMDQ_ERR_CERROR_ABT_IDX]	= "Abort on command fetch",
+		[CMDQ_ERR_CERROR_ATC_INV_IDX]	= "ATC invalidate timeout",
+	};
+
+	int i;
+	u64 cmd[CMDQ_ENT_DWORDS];
+	struct arm_smmu_queue *q = &smmu->cmdq.q;
+	u32 cons = readl_relaxed(q->cons_reg);
+	u32 idx = FIELD_GET(CMDQ_CONS_ERR, cons);
+	struct arm_smmu_cmdq_ent cmd_sync = {
+		.opcode = CMDQ_OP_CMD_SYNC,
+	};
+
+	dev_err(smmu->dev, "CMDQ error (cons 0x%08x): %s\n", cons,
+		idx < ARRAY_SIZE(cerror_str) ?  cerror_str[idx] : "Unknown");
+
+	switch (idx) {
+	case CMDQ_ERR_CERROR_ABT_IDX:
+		dev_err(smmu->dev, "retrying command fetch\n");
+	case CMDQ_ERR_CERROR_NONE_IDX:
+		return;
+	case CMDQ_ERR_CERROR_ATC_INV_IDX:
+		/*
+		 * ATC Invalidation Completion timeout. CONS is still pointing
+		 * at the CMD_SYNC. Attempt to complete other pending commands
+		 * by repeating the CMD_SYNC, though we might well end up back
+		 * here since the ATC invalidation may still be pending.
+		 */
+		return;
+	case CMDQ_ERR_CERROR_ILL_IDX:
+		/* Fallthrough */
+	default:
+		break;
+	}
+
+	/*
+	 * We may have concurrent producers, so we need to be careful
+	 * not to touch any of the shadow cmdq state.
+	 */
+	queue_read(cmd, Q_ENT(q, cons), q->ent_dwords);
+	dev_err(smmu->dev, "skipping command in error state:\n");
+	for (i = 0; i < ARRAY_SIZE(cmd); ++i)
+		dev_err(smmu->dev, "\t0x%016llx\n", (unsigned long long)cmd[i]);
+
+	/* Convert the erroneous command into a CMD_SYNC */
+	if (arm_smmu_cmdq_build_cmd(cmd, &cmd_sync)) {
+		dev_err(smmu->dev, "failed to convert to CMD_SYNC\n");
+		return;
+	}
+
+	queue_write(Q_ENT(q, cons), cmd, q->ent_dwords);
+}
+
+/*
+ * Command queue locking.
+ * This is a form of bastardised rwlock with the following major changes:
+ *
+ * - The only LOCK routines are exclusive_trylock() and shared_lock().
+ *   Neither have barrier semantics, and instead provide only a control
+ *   dependency.
+ *
+ * - The UNLOCK routines are supplemented with shared_tryunlock(), which
+ *   fails if the caller appears to be the last lock holder (yes, this is
+ *   racy). All successful UNLOCK routines have RELEASE semantics.
+ */
+static void arm_smmu_cmdq_shared_lock(struct arm_smmu_cmdq *cmdq)
+{
+	int val;
+
+	/*
+	 * We can try to avoid the cmpxchg() loop by simply incrementing the
+	 * lock counter. When held in exclusive state, the lock counter is set
+	 * to INT_MIN so these increments won't hurt as the value will remain
+	 * negative.
+	 */
+	if (atomic_fetch_inc_relaxed(&cmdq->lock) >= 0)
+		return;
+
+	do {
+		val = atomic_cond_read_relaxed(&cmdq->lock, VAL >= 0);
+	} while (atomic_cmpxchg_relaxed(&cmdq->lock, val, val + 1) != val);
+}
+
+static void arm_smmu_cmdq_shared_unlock(struct arm_smmu_cmdq *cmdq)
+{
+	(void)atomic_dec_return_release(&cmdq->lock);
+}
+
+static bool arm_smmu_cmdq_shared_tryunlock(struct arm_smmu_cmdq *cmdq)
+{
+	if (atomic_read(&cmdq->lock) == 1)
+		return false;
+
+	arm_smmu_cmdq_shared_unlock(cmdq);
+	return true;
+}
+
+#define arm_smmu_cmdq_exclusive_trylock_irqsave(cmdq, flags)		\
+({									\
+	bool __ret;							\
+	local_irq_save(flags);						\
+	__ret = !atomic_cmpxchg_relaxed(&cmdq->lock, 0, INT_MIN);	\
+	if (!__ret)							\
+		local_irq_restore(flags);				\
+	__ret;								\
+})
+
+#define arm_smmu_cmdq_exclusive_unlock_irqrestore(cmdq, flags)		\
+({									\
+	atomic_set_release(&cmdq->lock, 0);				\
+	local_irq_restore(flags);					\
+})
+
+
+/*
+ * Command queue insertion.
+ * This is made fiddly by our attempts to achieve some sort of scalability
+ * since there is one queue shared amongst all of the CPUs in the system.  If
+ * you like mixed-size concurrency, dependency ordering and relaxed atomics,
+ * then you'll *love* this monstrosity.
+ *
+ * The basic idea is to split the queue up into ranges of commands that are
+ * owned by a given CPU; the owner may not have written all of the commands
+ * itself, but is responsible for advancing the hardware prod pointer when
+ * the time comes. The algorithm is roughly:
+ *
+ * 	1. Allocate some space in the queue. At this point we also discover
+ *	   whether the head of the queue is currently owned by another CPU,
+ *	   or whether we are the owner.
+ *
+ *	2. Write our commands into our allocated slots in the queue.
+ *
+ *	3. Mark our slots as valid in arm_smmu_cmdq.valid_map.
+ *
+ *	4. If we are an owner:
+ *		a. Wait for the previous owner to finish.
+ *		b. Mark the queue head as unowned, which tells us the range
+ *		   that we are responsible for publishing.
+ *		c. Wait for all commands in our owned range to become valid.
+ *		d. Advance the hardware prod pointer.
+ *		e. Tell the next owner we've finished.
+ *
+ *	5. If we are inserting a CMD_SYNC (we may or may not have been an
+ *	   owner), then we need to stick around until it has completed:
+ *		a. If we have MSIs, the SMMU can write back into the CMD_SYNC
+ *		   to clear the first 4 bytes.
+ *		b. Otherwise, we spin waiting for the hardware cons pointer to
+ *		   advance past our command.
+ *
+ * The devil is in the details, particularly the use of locking for handling
+ * SYNC completion and freeing up space in the queue before we think that it is
+ * full.
+ */
+static void __arm_smmu_cmdq_poll_set_valid_map(struct arm_smmu_cmdq *cmdq,
+					       u32 sprod, u32 eprod, bool set)
+{
+	u32 swidx, sbidx, ewidx, ebidx;
+	struct arm_smmu_ll_queue llq = {
+		.max_n_shift	= cmdq->q.llq.max_n_shift,
+		.prod		= sprod,
+	};
+
+	ewidx = BIT_WORD(Q_IDX(&llq, eprod));
+	ebidx = Q_IDX(&llq, eprod) % BITS_PER_LONG;
+
+	while (llq.prod != eprod) {
+		unsigned long mask;
+		atomic_long_t *ptr;
+		u32 limit = BITS_PER_LONG;
+
+		swidx = BIT_WORD(Q_IDX(&llq, llq.prod));
+		sbidx = Q_IDX(&llq, llq.prod) % BITS_PER_LONG;
+
+		ptr = &cmdq->valid_map[swidx];
+
+		if ((swidx == ewidx) && (sbidx < ebidx))
+			limit = ebidx;
+
+		mask = GENMASK(limit - 1, sbidx);
+
+		/*
+		 * The valid bit is the inverse of the wrap bit. This means
+		 * that a zero-initialised queue is invalid and, after marking
+		 * all entries as valid, they become invalid again when we
+		 * wrap.
+		 */
+		if (set) {
+			atomic_long_xor(mask, ptr);
+		} else { /* Poll */
+			unsigned long valid;
+
+			valid = (ULONG_MAX + !!Q_WRP(&llq, llq.prod)) & mask;
+			atomic_long_cond_read_relaxed(ptr, (VAL & mask) == valid);
+		}
+
+		llq.prod = queue_inc_prod_n(&llq, limit - sbidx);
+	}
+}
+
+/* Mark all entries in the range [sprod, eprod) as valid */
+static void arm_smmu_cmdq_set_valid_map(struct arm_smmu_cmdq *cmdq,
+					u32 sprod, u32 eprod)
+{
+	__arm_smmu_cmdq_poll_set_valid_map(cmdq, sprod, eprod, true);
+}
+
+/* Wait for all entries in the range [sprod, eprod) to become valid */
+static void arm_smmu_cmdq_poll_valid_map(struct arm_smmu_cmdq *cmdq,
+					 u32 sprod, u32 eprod)
+{
+	__arm_smmu_cmdq_poll_set_valid_map(cmdq, sprod, eprod, false);
+}
+
+/* Wait for the command queue to become non-full */
+static int arm_smmu_cmdq_poll_until_not_full(struct arm_smmu_device *smmu,
+					     struct arm_smmu_ll_queue *llq)
+{
+	unsigned long flags;
+	struct arm_smmu_queue_poll qp;
+	struct arm_smmu_cmdq *cmdq = &smmu->cmdq;
+	int ret = 0;
+
+	/*
+	 * Try to update our copy of cons by grabbing exclusive cmdq access. If
+	 * that fails, spin until somebody else updates it for us.
+	 */
+	if (arm_smmu_cmdq_exclusive_trylock_irqsave(cmdq, flags)) {
+		WRITE_ONCE(cmdq->q.llq.cons, readl_relaxed(cmdq->q.cons_reg));
+		arm_smmu_cmdq_exclusive_unlock_irqrestore(cmdq, flags);
+		llq->val = READ_ONCE(cmdq->q.llq.val);
+		return 0;
+	}
+
+	queue_poll_init(smmu, &qp);
+	do {
+		llq->val = READ_ONCE(smmu->cmdq.q.llq.val);
+		if (!queue_full(llq))
+			break;
+
+		ret = queue_poll(&qp);
+	} while (!ret);
+
+	return ret;
+}
+
+/*
+ * Wait until the SMMU signals a CMD_SYNC completion MSI.
+ * Must be called with the cmdq lock held in some capacity.
+ */
+static int __arm_smmu_cmdq_poll_until_msi(struct arm_smmu_device *smmu,
+					  struct arm_smmu_ll_queue *llq)
+{
+	int ret = 0;
+	struct arm_smmu_queue_poll qp;
+	struct arm_smmu_cmdq *cmdq = &smmu->cmdq;
+	u32 *cmd = (u32 *)(Q_ENT(&cmdq->q, llq->prod));
+
+	queue_poll_init(smmu, &qp);
+
+	/*
+	 * The MSI won't generate an event, since it's being written back
+	 * into the command queue.
+	 */
+	qp.wfe = false;
+	smp_cond_load_relaxed(cmd, !VAL || (ret = queue_poll(&qp)));
+	llq->cons = ret ? llq->prod : queue_inc_prod_n(llq, 1);
+	return ret;
+}
+
+/*
+ * Wait until the SMMU cons index passes llq->prod.
+ * Must be called with the cmdq lock held in some capacity.
+ */
+static int __arm_smmu_cmdq_poll_until_consumed(struct arm_smmu_device *smmu,
+					       struct arm_smmu_ll_queue *llq)
+{
+	struct arm_smmu_queue_poll qp;
+	struct arm_smmu_cmdq *cmdq = &smmu->cmdq;
+	u32 prod = llq->prod;
+	int ret = 0;
+
+	queue_poll_init(smmu, &qp);
+	llq->val = READ_ONCE(smmu->cmdq.q.llq.val);
+	do {
+		if (queue_consumed(llq, prod))
+			break;
+
+		ret = queue_poll(&qp);
+
+		/*
+		 * This needs to be a readl() so that our subsequent call
+		 * to arm_smmu_cmdq_shared_tryunlock() can fail accurately.
+		 *
+		 * Specifically, we need to ensure that we observe all
+		 * shared_lock()s by other CMD_SYNCs that share our owner,
+		 * so that a failing call to tryunlock() means that we're
+		 * the last one out and therefore we can safely advance
+		 * cmdq->q.llq.cons. Roughly speaking:
+		 *
+		 * CPU 0		CPU1			CPU2 (us)
+		 *
+		 * if (sync)
+		 * 	shared_lock();
+		 *
+		 * dma_wmb();
+		 * set_valid_map();
+		 *
+		 * 			if (owner) {
+		 *				poll_valid_map();
+		 *				<control dependency>
+		 *				writel(prod_reg);
+		 *
+		 *						readl(cons_reg);
+		 *						tryunlock();
+		 *
+		 * Requires us to see CPU 0's shared_lock() acquisition.
+		 */
+		llq->cons = readl(cmdq->q.cons_reg);
+	} while (!ret);
+
+	return ret;
+}
+
+static int arm_smmu_cmdq_poll_until_sync(struct arm_smmu_device *smmu,
+					 struct arm_smmu_ll_queue *llq)
+{
+	if (smmu->features & ARM_SMMU_FEAT_MSI &&
+	    smmu->features & ARM_SMMU_FEAT_COHERENCY)
+		return __arm_smmu_cmdq_poll_until_msi(smmu, llq);
+
+	return __arm_smmu_cmdq_poll_until_consumed(smmu, llq);
+}
+
+static void arm_smmu_cmdq_write_entries(struct arm_smmu_cmdq *cmdq, u64 *cmds,
+					u32 prod, int n)
+{
+	int i;
+	struct arm_smmu_ll_queue llq = {
+		.max_n_shift	= cmdq->q.llq.max_n_shift,
+		.prod		= prod,
+	};
+
+	for (i = 0; i < n; ++i) {
+		u64 *cmd = &cmds[i * CMDQ_ENT_DWORDS];
+
+		prod = queue_inc_prod_n(&llq, i);
+		queue_write(Q_ENT(&cmdq->q, prod), cmd, CMDQ_ENT_DWORDS);
+	}
+}
+
+/*
+ * This is the actual insertion function, and provides the following
+ * ordering guarantees to callers:
+ *
+ * - There is a dma_wmb() before publishing any commands to the queue.
+ *   This can be relied upon to order prior writes to data structures
+ *   in memory (such as a CD or an STE) before the command.
+ *
+ * - On completion of a CMD_SYNC, there is a control dependency.
+ *   This can be relied upon to order subsequent writes to memory (e.g.
+ *   freeing an IOVA) after completion of the CMD_SYNC.
+ *
+ * - Command insertion is totally ordered, so if two CPUs each race to
+ *   insert their own list of commands then all of the commands from one
+ *   CPU will appear before any of the commands from the other CPU.
+ */
+static int arm_smmu_cmdq_issue_cmdlist(struct arm_smmu_device *smmu,
+				       u64 *cmds, int n, bool sync)
+{
+	u64 cmd_sync[CMDQ_ENT_DWORDS];
+	u32 prod;
+	unsigned long flags;
+	bool owner;
+	struct arm_smmu_cmdq *cmdq = &smmu->cmdq;
+	struct arm_smmu_ll_queue llq = {
+		.max_n_shift = cmdq->q.llq.max_n_shift,
+	}, head = llq;
+	int ret = 0;
+
+	/* 1. Allocate some space in the queue */
+	local_irq_save(flags);
+	llq.val = READ_ONCE(cmdq->q.llq.val);
+	do {
+		u64 old;
+
+		while (!queue_has_space(&llq, n + sync)) {
+			local_irq_restore(flags);
+			if (arm_smmu_cmdq_poll_until_not_full(smmu, &llq))
+				dev_err_ratelimited(smmu->dev, "CMDQ timeout\n");
+			local_irq_save(flags);
+		}
+
+		head.cons = llq.cons;
+		head.prod = queue_inc_prod_n(&llq, n + sync) |
+					     CMDQ_PROD_OWNED_FLAG;
+
+		old = cmpxchg_relaxed(&cmdq->q.llq.val, llq.val, head.val);
+		if (old == llq.val)
+			break;
+
+		llq.val = old;
+	} while (1);
+	owner = !(llq.prod & CMDQ_PROD_OWNED_FLAG);
+	head.prod &= ~CMDQ_PROD_OWNED_FLAG;
+	llq.prod &= ~CMDQ_PROD_OWNED_FLAG;
+
+	/*
+	 * 2. Write our commands into the queue
+	 * Dependency ordering from the cmpxchg() loop above.
+	 */
+	arm_smmu_cmdq_write_entries(cmdq, cmds, llq.prod, n);
+	if (sync) {
+		prod = queue_inc_prod_n(&llq, n);
+		arm_smmu_cmdq_build_sync_cmd(cmd_sync, smmu, prod);
+		queue_write(Q_ENT(&cmdq->q, prod), cmd_sync, CMDQ_ENT_DWORDS);
+
+		/*
+		 * In order to determine completion of our CMD_SYNC, we must
+		 * ensure that the queue can't wrap twice without us noticing.
+		 * We achieve that by taking the cmdq lock as shared before
+		 * marking our slot as valid.
+		 */
+		arm_smmu_cmdq_shared_lock(cmdq);
+	}
+
+	/* 3. Mark our slots as valid, ensuring commands are visible first */
+	dma_wmb();
+	arm_smmu_cmdq_set_valid_map(cmdq, llq.prod, head.prod);
+
+	/* 4. If we are the owner, take control of the SMMU hardware */
+	if (owner) {
+		/* a. Wait for previous owner to finish */
+		atomic_cond_read_relaxed(&cmdq->owner_prod, VAL == llq.prod);
+
+		/* b. Stop gathering work by clearing the owned flag */
+		prod = atomic_fetch_andnot_relaxed(CMDQ_PROD_OWNED_FLAG,
+						   &cmdq->q.llq.atomic.prod);
+		prod &= ~CMDQ_PROD_OWNED_FLAG;
+
+		/*
+		 * c. Wait for any gathered work to be written to the queue.
+		 * Note that we read our own entries so that we have the control
+		 * dependency required by (d).
+		 */
+		arm_smmu_cmdq_poll_valid_map(cmdq, llq.prod, prod);
+
+		/*
+		 * d. Advance the hardware prod pointer
+		 * Control dependency ordering from the entries becoming valid.
+		 */
+		writel_relaxed(prod, cmdq->q.prod_reg);
+
+		/*
+		 * e. Tell the next owner we're done
+		 * Make sure we've updated the hardware first, so that we don't
+		 * race to update prod and potentially move it backwards.
+		 */
+		atomic_set_release(&cmdq->owner_prod, prod);
+	}
+
+	/* 5. If we are inserting a CMD_SYNC, we must wait for it to complete */
+	if (sync) {
+		llq.prod = queue_inc_prod_n(&llq, n);
+		ret = arm_smmu_cmdq_poll_until_sync(smmu, &llq);
+		if (ret) {
+			dev_err_ratelimited(smmu->dev,
+					    "CMD_SYNC timeout at 0x%08x [hwprod 0x%08x, hwcons 0x%08x]\n",
+					    llq.prod,
+					    readl_relaxed(cmdq->q.prod_reg),
+					    readl_relaxed(cmdq->q.cons_reg));
+		}
+
+		/*
+		 * Try to unlock the cmq lock. This will fail if we're the last
+		 * reader, in which case we can safely update cmdq->q.llq.cons
+		 */
+		if (!arm_smmu_cmdq_shared_tryunlock(cmdq)) {
+			WRITE_ONCE(cmdq->q.llq.cons, llq.cons);
+			arm_smmu_cmdq_shared_unlock(cmdq);
+		}
+	}
+
+	local_irq_restore(flags);
+	return ret;
+}
+
+static int arm_smmu_cmdq_issue_cmd(struct arm_smmu_device *smmu,
+				   struct arm_smmu_cmdq_ent *ent)
+{
+	u64 cmd[CMDQ_ENT_DWORDS];
+
+	if (arm_smmu_cmdq_build_cmd(cmd, ent)) {
+		dev_warn(smmu->dev, "ignoring unknown CMDQ opcode 0x%x\n",
+			 ent->opcode);
+		return -EINVAL;
+	}
+
+	return arm_smmu_cmdq_issue_cmdlist(smmu, cmd, 1, false);
+}
+
+static int arm_smmu_cmdq_issue_sync(struct arm_smmu_device *smmu)
+{
+	return arm_smmu_cmdq_issue_cmdlist(smmu, NULL, 0, true);
+}
+
+static void arm_smmu_cmdq_batch_add(struct arm_smmu_device *smmu,
+				    struct arm_smmu_cmdq_batch *cmds,
+				    struct arm_smmu_cmdq_ent *cmd)
+{
+	if (cmds->num == CMDQ_BATCH_ENTRIES) {
+		arm_smmu_cmdq_issue_cmdlist(smmu, cmds->cmds, cmds->num, false);
+		cmds->num = 0;
+	}
+	arm_smmu_cmdq_build_cmd(&cmds->cmds[cmds->num * CMDQ_ENT_DWORDS], cmd);
+	cmds->num++;
+}
+
+static int arm_smmu_cmdq_batch_submit(struct arm_smmu_device *smmu,
+				      struct arm_smmu_cmdq_batch *cmds)
+{
+	return arm_smmu_cmdq_issue_cmdlist(smmu, cmds->cmds, cmds->num, true);
+}
+
+/* Context descriptor manipulation functions */
+static void arm_smmu_sync_cd(struct arm_smmu_domain *smmu_domain,
+			     int ssid, bool leaf)
+{
+	size_t i;
+	unsigned long flags;
+	struct arm_smmu_master *master;
+	struct arm_smmu_cmdq_batch cmds = {};
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
+	struct arm_smmu_cmdq_ent cmd = {
+		.opcode	= CMDQ_OP_CFGI_CD,
+		.cfgi	= {
+			.ssid	= ssid,
+			.leaf	= leaf,
+		},
+	};
+
+	spin_lock_irqsave(&smmu_domain->devices_lock, flags);
+	list_for_each_entry(master, &smmu_domain->devices, domain_head) {
+		for (i = 0; i < master->num_sids; i++) {
+			cmd.cfgi.sid = master->sids[i];
+			arm_smmu_cmdq_batch_add(smmu, &cmds, &cmd);
+		}
+	}
+	spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
+
+	arm_smmu_cmdq_batch_submit(smmu, &cmds);
+}
+
+static int arm_smmu_alloc_cd_leaf_table(struct arm_smmu_device *smmu,
+					struct arm_smmu_l1_ctx_desc *l1_desc)
+{
+	size_t size = CTXDESC_L2_ENTRIES * (CTXDESC_CD_DWORDS << 3);
+
+	l1_desc->l2ptr = dmam_alloc_coherent(smmu->dev, size,
+					     &l1_desc->l2ptr_dma, GFP_KERNEL);
+	if (!l1_desc->l2ptr) {
+		dev_warn(smmu->dev,
+			 "failed to allocate context descriptor table\n");
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+static void arm_smmu_write_cd_l1_desc(__le64 *dst,
+				      struct arm_smmu_l1_ctx_desc *l1_desc)
+{
+	u64 val = (l1_desc->l2ptr_dma & CTXDESC_L1_DESC_L2PTR_MASK) |
+		  CTXDESC_L1_DESC_V;
+
+	/* See comment in arm_smmu_write_ctx_desc() */
+	WRITE_ONCE(*dst, cpu_to_le64(val));
+}
+
+static __le64 *arm_smmu_get_cd_ptr(struct arm_smmu_domain *smmu_domain,
+				   u32 ssid)
+{
+	__le64 *l1ptr;
+	unsigned int idx;
+	struct arm_smmu_l1_ctx_desc *l1_desc;
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
+	struct arm_smmu_ctx_desc_cfg *cdcfg = &smmu_domain->s1_cfg.cdcfg;
+
+	if (smmu_domain->s1_cfg.s1fmt == STRTAB_STE_0_S1FMT_LINEAR)
+		return cdcfg->cdtab + ssid * CTXDESC_CD_DWORDS;
+
+	idx = ssid >> CTXDESC_SPLIT;
+	l1_desc = &cdcfg->l1_desc[idx];
+	if (!l1_desc->l2ptr) {
+		if (arm_smmu_alloc_cd_leaf_table(smmu, l1_desc))
+			return NULL;
+
+		l1ptr = cdcfg->cdtab + idx * CTXDESC_L1_DESC_DWORDS;
+		arm_smmu_write_cd_l1_desc(l1ptr, l1_desc);
+		/* An invalid L1CD can be cached */
+		arm_smmu_sync_cd(smmu_domain, ssid, false);
+	}
+	idx = ssid & (CTXDESC_L2_ENTRIES - 1);
+	return l1_desc->l2ptr + idx * CTXDESC_CD_DWORDS;
+}
+
+static int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain,
+				   int ssid, struct arm_smmu_ctx_desc *cd)
+{
+	/*
+	 * This function handles the following cases:
+	 *
+	 * (1) Install primary CD, for normal DMA traffic (SSID = 0).
+	 * (2) Install a secondary CD, for SID+SSID traffic.
+	 * (3) Update ASID of a CD. Atomically write the first 64 bits of the
+	 *     CD, then invalidate the old entry and mappings.
+	 * (4) Remove a secondary CD.
+	 */
+	u64 val;
+	bool cd_live;
+	__le64 *cdptr;
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
+
+	if (WARN_ON(ssid >= (1 << smmu_domain->s1_cfg.s1cdmax)))
+		return -E2BIG;
+
+	cdptr = arm_smmu_get_cd_ptr(smmu_domain, ssid);
+	if (!cdptr)
+		return -ENOMEM;
+
+	val = le64_to_cpu(cdptr[0]);
+	cd_live = !!(val & CTXDESC_CD_0_V);
+
+	if (!cd) { /* (4) */
+		val = 0;
+	} else if (cd_live) { /* (3) */
+		val &= ~CTXDESC_CD_0_ASID;
+		val |= FIELD_PREP(CTXDESC_CD_0_ASID, cd->asid);
+		/*
+		 * Until CD+TLB invalidation, both ASIDs may be used for tagging
+		 * this substream's traffic
+		 */
+	} else { /* (1) and (2) */
+		cdptr[1] = cpu_to_le64(cd->ttbr & CTXDESC_CD_1_TTB0_MASK);
+		cdptr[2] = 0;
+		cdptr[3] = cpu_to_le64(cd->mair);
+
+		/*
+		 * STE is live, and the SMMU might read dwords of this CD in any
+		 * order. Ensure that it observes valid values before reading
+		 * V=1.
+		 */
+		arm_smmu_sync_cd(smmu_domain, ssid, true);
+
+		val = cd->tcr |
+#ifdef __BIG_ENDIAN
+			CTXDESC_CD_0_ENDI |
+#endif
+			CTXDESC_CD_0_R | CTXDESC_CD_0_A | CTXDESC_CD_0_ASET |
+			CTXDESC_CD_0_AA64 |
+			FIELD_PREP(CTXDESC_CD_0_ASID, cd->asid) |
+			CTXDESC_CD_0_V;
+
+		/* STALL_MODEL==0b10 && CD.S==0 is ILLEGAL */
+		if (smmu->features & ARM_SMMU_FEAT_STALL_FORCE)
+			val |= CTXDESC_CD_0_S;
+	}
+
+	/*
+	 * The SMMU accesses 64-bit values atomically. See IHI0070Ca 3.21.3
+	 * "Configuration structures and configuration invalidation completion"
+	 *
+	 *   The size of single-copy atomic reads made by the SMMU is
+	 *   IMPLEMENTATION DEFINED but must be at least 64 bits. Any single
+	 *   field within an aligned 64-bit span of a structure can be altered
+	 *   without first making the structure invalid.
+	 */
+	WRITE_ONCE(cdptr[0], cpu_to_le64(val));
+	arm_smmu_sync_cd(smmu_domain, ssid, true);
+	return 0;
+}
+
+static int arm_smmu_alloc_cd_tables(struct arm_smmu_domain *smmu_domain)
+{
+	int ret;
+	size_t l1size;
+	size_t max_contexts;
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
+	struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
+	struct arm_smmu_ctx_desc_cfg *cdcfg = &cfg->cdcfg;
+
+	max_contexts = 1 << cfg->s1cdmax;
+
+	if (!(smmu->features & ARM_SMMU_FEAT_2_LVL_CDTAB) ||
+	    max_contexts <= CTXDESC_L2_ENTRIES) {
+		cfg->s1fmt = STRTAB_STE_0_S1FMT_LINEAR;
+		cdcfg->num_l1_ents = max_contexts;
+
+		l1size = max_contexts * (CTXDESC_CD_DWORDS << 3);
+	} else {
+		cfg->s1fmt = STRTAB_STE_0_S1FMT_64K_L2;
+		cdcfg->num_l1_ents = DIV_ROUND_UP(max_contexts,
+						  CTXDESC_L2_ENTRIES);
+
+		cdcfg->l1_desc = devm_kcalloc(smmu->dev, cdcfg->num_l1_ents,
+					      sizeof(*cdcfg->l1_desc),
+					      GFP_KERNEL);
+		if (!cdcfg->l1_desc)
+			return -ENOMEM;
+
+		l1size = cdcfg->num_l1_ents * (CTXDESC_L1_DESC_DWORDS << 3);
+	}
+
+	cdcfg->cdtab = dmam_alloc_coherent(smmu->dev, l1size, &cdcfg->cdtab_dma,
+					   GFP_KERNEL);
+	if (!cdcfg->cdtab) {
+		dev_warn(smmu->dev, "failed to allocate context descriptor\n");
+		ret = -ENOMEM;
+		goto err_free_l1;
+	}
+
+	return 0;
+
+err_free_l1:
+	if (cdcfg->l1_desc) {
+		devm_kfree(smmu->dev, cdcfg->l1_desc);
+		cdcfg->l1_desc = NULL;
+	}
+	return ret;
+}
+
+static void arm_smmu_free_cd_tables(struct arm_smmu_domain *smmu_domain)
+{
+	int i;
+	size_t size, l1size;
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
+	struct arm_smmu_ctx_desc_cfg *cdcfg = &smmu_domain->s1_cfg.cdcfg;
+
+	if (cdcfg->l1_desc) {
+		size = CTXDESC_L2_ENTRIES * (CTXDESC_CD_DWORDS << 3);
+
+		for (i = 0; i < cdcfg->num_l1_ents; i++) {
+			if (!cdcfg->l1_desc[i].l2ptr)
+				continue;
+
+			dmam_free_coherent(smmu->dev, size,
+					   cdcfg->l1_desc[i].l2ptr,
+					   cdcfg->l1_desc[i].l2ptr_dma);
+		}
+		devm_kfree(smmu->dev, cdcfg->l1_desc);
+		cdcfg->l1_desc = NULL;
+
+		l1size = cdcfg->num_l1_ents * (CTXDESC_L1_DESC_DWORDS << 3);
+	} else {
+		l1size = cdcfg->num_l1_ents * (CTXDESC_CD_DWORDS << 3);
+	}
+
+	dmam_free_coherent(smmu->dev, l1size, cdcfg->cdtab, cdcfg->cdtab_dma);
+	cdcfg->cdtab_dma = 0;
+	cdcfg->cdtab = NULL;
+}
+
+static void arm_smmu_free_asid(struct arm_smmu_ctx_desc *cd)
+{
+	if (!cd->asid)
+		return;
+
+	xa_erase(&asid_xa, cd->asid);
+}
+
+/* Stream table manipulation functions */
+static void
+arm_smmu_write_strtab_l1_desc(__le64 *dst, struct arm_smmu_strtab_l1_desc *desc)
+{
+	u64 val = 0;
+
+	val |= FIELD_PREP(STRTAB_L1_DESC_SPAN, desc->span);
+	val |= desc->l2ptr_dma & STRTAB_L1_DESC_L2PTR_MASK;
+
+	/* See comment in arm_smmu_write_ctx_desc() */
+	WRITE_ONCE(*dst, cpu_to_le64(val));
+}
+
+static void arm_smmu_sync_ste_for_sid(struct arm_smmu_device *smmu, u32 sid)
+{
+	struct arm_smmu_cmdq_ent cmd = {
+		.opcode	= CMDQ_OP_CFGI_STE,
+		.cfgi	= {
+			.sid	= sid,
+			.leaf	= true,
+		},
+	};
+
+	arm_smmu_cmdq_issue_cmd(smmu, &cmd);
+	arm_smmu_cmdq_issue_sync(smmu);
+}
+
+static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
+				      __le64 *dst)
+{
+	/*
+	 * This is hideously complicated, but we only really care about
+	 * three cases at the moment:
+	 *
+	 * 1. Invalid (all zero) -> bypass/fault (init)
+	 * 2. Bypass/fault -> translation/bypass (attach)
+	 * 3. Translation/bypass -> bypass/fault (detach)
+	 *
+	 * Given that we can't update the STE atomically and the SMMU
+	 * doesn't read the thing in a defined order, that leaves us
+	 * with the following maintenance requirements:
+	 *
+	 * 1. Update Config, return (init time STEs aren't live)
+	 * 2. Write everything apart from dword 0, sync, write dword 0, sync
+	 * 3. Update Config, sync
+	 */
+	u64 val = le64_to_cpu(dst[0]);
+	bool ste_live = false;
+	struct arm_smmu_device *smmu = NULL;
+	struct arm_smmu_s1_cfg *s1_cfg = NULL;
+	struct arm_smmu_s2_cfg *s2_cfg = NULL;
+	struct arm_smmu_domain *smmu_domain = NULL;
+	struct arm_smmu_cmdq_ent prefetch_cmd = {
+		.opcode		= CMDQ_OP_PREFETCH_CFG,
+		.prefetch	= {
+			.sid	= sid,
+		},
+	};
+
+	if (master) {
+		smmu_domain = master->domain;
+		smmu = master->smmu;
+	}
+
+	if (smmu_domain) {
+		switch (smmu_domain->stage) {
+		case ARM_SMMU_DOMAIN_S1:
+			s1_cfg = &smmu_domain->s1_cfg;
+			break;
+		case ARM_SMMU_DOMAIN_S2:
+		case ARM_SMMU_DOMAIN_NESTED:
+			s2_cfg = &smmu_domain->s2_cfg;
+			break;
+		default:
+			break;
+		}
+	}
+
+	if (val & STRTAB_STE_0_V) {
+		switch (FIELD_GET(STRTAB_STE_0_CFG, val)) {
+		case STRTAB_STE_0_CFG_BYPASS:
+			break;
+		case STRTAB_STE_0_CFG_S1_TRANS:
+		case STRTAB_STE_0_CFG_S2_TRANS:
+			ste_live = true;
+			break;
+		case STRTAB_STE_0_CFG_ABORT:
+			BUG_ON(!disable_bypass);
+			break;
+		default:
+			BUG(); /* STE corruption */
+		}
+	}
+
+	/* Nuke the existing STE_0 value, as we're going to rewrite it */
+	val = STRTAB_STE_0_V;
+
+	/* Bypass/fault */
+	if (!smmu_domain || !(s1_cfg || s2_cfg)) {
+		if (!smmu_domain && disable_bypass)
+			val |= FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_ABORT);
+		else
+			val |= FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_BYPASS);
+
+		dst[0] = cpu_to_le64(val);
+		dst[1] = cpu_to_le64(FIELD_PREP(STRTAB_STE_1_SHCFG,
+						STRTAB_STE_1_SHCFG_INCOMING));
+		dst[2] = 0; /* Nuke the VMID */
+		/*
+		 * The SMMU can perform negative caching, so we must sync
+		 * the STE regardless of whether the old value was live.
+		 */
+		if (smmu)
+			arm_smmu_sync_ste_for_sid(smmu, sid);
+		return;
+	}
+
+	if (s1_cfg) {
+		BUG_ON(ste_live);
+		dst[1] = cpu_to_le64(
+			 FIELD_PREP(STRTAB_STE_1_S1DSS, STRTAB_STE_1_S1DSS_SSID0) |
+			 FIELD_PREP(STRTAB_STE_1_S1CIR, STRTAB_STE_1_S1C_CACHE_WBRA) |
+			 FIELD_PREP(STRTAB_STE_1_S1COR, STRTAB_STE_1_S1C_CACHE_WBRA) |
+			 FIELD_PREP(STRTAB_STE_1_S1CSH, ARM_SMMU_SH_ISH) |
+			 FIELD_PREP(STRTAB_STE_1_STRW, STRTAB_STE_1_STRW_NSEL1));
+
+		if (smmu->features & ARM_SMMU_FEAT_STALLS &&
+		   !(smmu->features & ARM_SMMU_FEAT_STALL_FORCE))
+			dst[1] |= cpu_to_le64(STRTAB_STE_1_S1STALLD);
+
+		val |= (s1_cfg->cdcfg.cdtab_dma & STRTAB_STE_0_S1CTXPTR_MASK) |
+			FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_S1_TRANS) |
+			FIELD_PREP(STRTAB_STE_0_S1CDMAX, s1_cfg->s1cdmax) |
+			FIELD_PREP(STRTAB_STE_0_S1FMT, s1_cfg->s1fmt);
+	}
+
+	if (s2_cfg) {
+		BUG_ON(ste_live);
+		dst[2] = cpu_to_le64(
+			 FIELD_PREP(STRTAB_STE_2_S2VMID, s2_cfg->vmid) |
+			 FIELD_PREP(STRTAB_STE_2_VTCR, s2_cfg->vtcr) |
+#ifdef __BIG_ENDIAN
+			 STRTAB_STE_2_S2ENDI |
+#endif
+			 STRTAB_STE_2_S2PTW | STRTAB_STE_2_S2AA64 |
+			 STRTAB_STE_2_S2R);
+
+		dst[3] = cpu_to_le64(s2_cfg->vttbr & STRTAB_STE_3_S2TTB_MASK);
+
+		val |= FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_S2_TRANS);
+	}
+
+	if (master->ats_enabled)
+		dst[1] |= cpu_to_le64(FIELD_PREP(STRTAB_STE_1_EATS,
+						 STRTAB_STE_1_EATS_TRANS));
+
+	arm_smmu_sync_ste_for_sid(smmu, sid);
+	/* See comment in arm_smmu_write_ctx_desc() */
+	WRITE_ONCE(dst[0], cpu_to_le64(val));
+	arm_smmu_sync_ste_for_sid(smmu, sid);
+
+	/* It's likely that we'll want to use the new STE soon */
+	if (!(smmu->options & ARM_SMMU_OPT_SKIP_PREFETCH))
+		arm_smmu_cmdq_issue_cmd(smmu, &prefetch_cmd);
+}
+
+static void arm_smmu_init_bypass_stes(u64 *strtab, unsigned int nent)
+{
+	unsigned int i;
+
+	for (i = 0; i < nent; ++i) {
+		arm_smmu_write_strtab_ent(NULL, -1, strtab);
+		strtab += STRTAB_STE_DWORDS;
+	}
+}
+
+static int arm_smmu_init_l2_strtab(struct arm_smmu_device *smmu, u32 sid)
+{
+	size_t size;
+	void *strtab;
+	struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg;
+	struct arm_smmu_strtab_l1_desc *desc = &cfg->l1_desc[sid >> STRTAB_SPLIT];
+
+	if (desc->l2ptr)
+		return 0;
+
+	size = 1 << (STRTAB_SPLIT + ilog2(STRTAB_STE_DWORDS) + 3);
+	strtab = &cfg->strtab[(sid >> STRTAB_SPLIT) * STRTAB_L1_DESC_DWORDS];
+
+	desc->span = STRTAB_SPLIT + 1;
+	desc->l2ptr = dmam_alloc_coherent(smmu->dev, size, &desc->l2ptr_dma,
+					  GFP_KERNEL);
+	if (!desc->l2ptr) {
+		dev_err(smmu->dev,
+			"failed to allocate l2 stream table for SID %u\n",
+			sid);
+		return -ENOMEM;
+	}
+
+	arm_smmu_init_bypass_stes(desc->l2ptr, 1 << STRTAB_SPLIT);
+	arm_smmu_write_strtab_l1_desc(strtab, desc);
+	return 0;
+}
+
+/* IRQ and event handlers */
+static irqreturn_t arm_smmu_evtq_thread(int irq, void *dev)
+{
+	int i;
+	struct arm_smmu_device *smmu = dev;
+	struct arm_smmu_queue *q = &smmu->evtq.q;
+	struct arm_smmu_ll_queue *llq = &q->llq;
+	u64 evt[EVTQ_ENT_DWORDS];
+
+	do {
+		while (!queue_remove_raw(q, evt)) {
+			u8 id = FIELD_GET(EVTQ_0_ID, evt[0]);
+
+			dev_info(smmu->dev, "event 0x%02x received:\n", id);
+			for (i = 0; i < ARRAY_SIZE(evt); ++i)
+				dev_info(smmu->dev, "\t0x%016llx\n",
+					 (unsigned long long)evt[i]);
+
+		}
+
+		/*
+		 * Not much we can do on overflow, so scream and pretend we're
+		 * trying harder.
+		 */
+		if (queue_sync_prod_in(q) == -EOVERFLOW)
+			dev_err(smmu->dev, "EVTQ overflow detected -- events lost\n");
+	} while (!queue_empty(llq));
+
+	/* Sync our overflow flag, as we believe we're up to speed */
+	llq->cons = Q_OVF(llq->prod) | Q_WRP(llq, llq->cons) |
+		    Q_IDX(llq, llq->cons);
+	return IRQ_HANDLED;
+}
+
+static void arm_smmu_handle_ppr(struct arm_smmu_device *smmu, u64 *evt)
+{
+	u32 sid, ssid;
+	u16 grpid;
+	bool ssv, last;
+
+	sid = FIELD_GET(PRIQ_0_SID, evt[0]);
+	ssv = FIELD_GET(PRIQ_0_SSID_V, evt[0]);
+	ssid = ssv ? FIELD_GET(PRIQ_0_SSID, evt[0]) : 0;
+	last = FIELD_GET(PRIQ_0_PRG_LAST, evt[0]);
+	grpid = FIELD_GET(PRIQ_1_PRG_IDX, evt[1]);
+
+	dev_info(smmu->dev, "unexpected PRI request received:\n");
+	dev_info(smmu->dev,
+		 "\tsid 0x%08x.0x%05x: [%u%s] %sprivileged %s%s%s access at iova 0x%016llx\n",
+		 sid, ssid, grpid, last ? "L" : "",
+		 evt[0] & PRIQ_0_PERM_PRIV ? "" : "un",
+		 evt[0] & PRIQ_0_PERM_READ ? "R" : "",
+		 evt[0] & PRIQ_0_PERM_WRITE ? "W" : "",
+		 evt[0] & PRIQ_0_PERM_EXEC ? "X" : "",
+		 evt[1] & PRIQ_1_ADDR_MASK);
+
+	if (last) {
+		struct arm_smmu_cmdq_ent cmd = {
+			.opcode			= CMDQ_OP_PRI_RESP,
+			.substream_valid	= ssv,
+			.pri			= {
+				.sid	= sid,
+				.ssid	= ssid,
+				.grpid	= grpid,
+				.resp	= PRI_RESP_DENY,
+			},
+		};
+
+		arm_smmu_cmdq_issue_cmd(smmu, &cmd);
+	}
+}
+
+static irqreturn_t arm_smmu_priq_thread(int irq, void *dev)
+{
+	struct arm_smmu_device *smmu = dev;
+	struct arm_smmu_queue *q = &smmu->priq.q;
+	struct arm_smmu_ll_queue *llq = &q->llq;
+	u64 evt[PRIQ_ENT_DWORDS];
+
+	do {
+		while (!queue_remove_raw(q, evt))
+			arm_smmu_handle_ppr(smmu, evt);
+
+		if (queue_sync_prod_in(q) == -EOVERFLOW)
+			dev_err(smmu->dev, "PRIQ overflow detected -- requests lost\n");
+	} while (!queue_empty(llq));
+
+	/* Sync our overflow flag, as we believe we're up to speed */
+	llq->cons = Q_OVF(llq->prod) | Q_WRP(llq, llq->cons) |
+		      Q_IDX(llq, llq->cons);
+	queue_sync_cons_out(q);
+	return IRQ_HANDLED;
+}
+
+static int arm_smmu_device_disable(struct arm_smmu_device *smmu);
+
+static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
+{
+	u32 gerror, gerrorn, active;
+	struct arm_smmu_device *smmu = dev;
+
+	gerror = readl_relaxed(smmu->base + ARM_SMMU_GERROR);
+	gerrorn = readl_relaxed(smmu->base + ARM_SMMU_GERRORN);
+
+	active = gerror ^ gerrorn;
+	if (!(active & GERROR_ERR_MASK))
+		return IRQ_NONE; /* No errors pending */
+
+	dev_warn(smmu->dev,
+		 "unexpected global error reported (0x%08x), this could be serious\n",
+		 active);
+
+	if (active & GERROR_SFM_ERR) {
+		dev_err(smmu->dev, "device has entered Service Failure Mode!\n");
+		arm_smmu_device_disable(smmu);
+	}
+
+	if (active & GERROR_MSI_GERROR_ABT_ERR)
+		dev_warn(smmu->dev, "GERROR MSI write aborted\n");
+
+	if (active & GERROR_MSI_PRIQ_ABT_ERR)
+		dev_warn(smmu->dev, "PRIQ MSI write aborted\n");
+
+	if (active & GERROR_MSI_EVTQ_ABT_ERR)
+		dev_warn(smmu->dev, "EVTQ MSI write aborted\n");
+
+	if (active & GERROR_MSI_CMDQ_ABT_ERR)
+		dev_warn(smmu->dev, "CMDQ MSI write aborted\n");
+
+	if (active & GERROR_PRIQ_ABT_ERR)
+		dev_err(smmu->dev, "PRIQ write aborted -- events may have been lost\n");
+
+	if (active & GERROR_EVTQ_ABT_ERR)
+		dev_err(smmu->dev, "EVTQ write aborted -- events may have been lost\n");
+
+	if (active & GERROR_CMDQ_ERR)
+		arm_smmu_cmdq_skip_err(smmu);
+
+	writel(gerror, smmu->base + ARM_SMMU_GERRORN);
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t arm_smmu_combined_irq_thread(int irq, void *dev)
+{
+	struct arm_smmu_device *smmu = dev;
+
+	arm_smmu_evtq_thread(irq, dev);
+	if (smmu->features & ARM_SMMU_FEAT_PRI)
+		arm_smmu_priq_thread(irq, dev);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t arm_smmu_combined_irq_handler(int irq, void *dev)
+{
+	arm_smmu_gerror_handler(irq, dev);
+	return IRQ_WAKE_THREAD;
+}
+
+static void
+arm_smmu_atc_inv_to_cmd(int ssid, unsigned long iova, size_t size,
+			struct arm_smmu_cmdq_ent *cmd)
+{
+	size_t log2_span;
+	size_t span_mask;
+	/* ATC invalidates are always on 4096-bytes pages */
+	size_t inval_grain_shift = 12;
+	unsigned long page_start, page_end;
+
+	*cmd = (struct arm_smmu_cmdq_ent) {
+		.opcode			= CMDQ_OP_ATC_INV,
+		.substream_valid	= !!ssid,
+		.atc.ssid		= ssid,
+	};
+
+	if (!size) {
+		cmd->atc.size = ATC_INV_SIZE_ALL;
+		return;
+	}
+
+	page_start	= iova >> inval_grain_shift;
+	page_end	= (iova + size - 1) >> inval_grain_shift;
+
+	/*
+	 * In an ATS Invalidate Request, the address must be aligned on the
+	 * range size, which must be a power of two number of page sizes. We
+	 * thus have to choose between grossly over-invalidating the region, or
+	 * splitting the invalidation into multiple commands. For simplicity
+	 * we'll go with the first solution, but should refine it in the future
+	 * if multiple commands are shown to be more efficient.
+	 *
+	 * Find the smallest power of two that covers the range. The most
+	 * significant differing bit between the start and end addresses,
+	 * fls(start ^ end), indicates the required span. For example:
+	 *
+	 * We want to invalidate pages [8; 11]. This is already the ideal range:
+	 *		x = 0b1000 ^ 0b1011 = 0b11
+	 *		span = 1 << fls(x) = 4
+	 *
+	 * To invalidate pages [7; 10], we need to invalidate [0; 15]:
+	 *		x = 0b0111 ^ 0b1010 = 0b1101
+	 *		span = 1 << fls(x) = 16
+	 */
+	log2_span	= fls_long(page_start ^ page_end);
+	span_mask	= (1ULL << log2_span) - 1;
+
+	page_start	&= ~span_mask;
+
+	cmd->atc.addr	= page_start << inval_grain_shift;
+	cmd->atc.size	= log2_span;
+}
+
+static int arm_smmu_atc_inv_master(struct arm_smmu_master *master)
+{
+	int i;
+	struct arm_smmu_cmdq_ent cmd;
+
+	arm_smmu_atc_inv_to_cmd(0, 0, 0, &cmd);
+
+	for (i = 0; i < master->num_sids; i++) {
+		cmd.atc.sid = master->sids[i];
+		arm_smmu_cmdq_issue_cmd(master->smmu, &cmd);
+	}
+
+	return arm_smmu_cmdq_issue_sync(master->smmu);
+}
+
+static int arm_smmu_atc_inv_domain(struct arm_smmu_domain *smmu_domain,
+				   int ssid, unsigned long iova, size_t size)
+{
+	int i;
+	unsigned long flags;
+	struct arm_smmu_cmdq_ent cmd;
+	struct arm_smmu_master *master;
+	struct arm_smmu_cmdq_batch cmds = {};
+
+	if (!(smmu_domain->smmu->features & ARM_SMMU_FEAT_ATS))
+		return 0;
+
+	/*
+	 * Ensure that we've completed prior invalidation of the main TLBs
+	 * before we read 'nr_ats_masters' in case of a concurrent call to
+	 * arm_smmu_enable_ats():
+	 *
+	 *	// unmap()			// arm_smmu_enable_ats()
+	 *	TLBI+SYNC			atomic_inc(&nr_ats_masters);
+	 *	smp_mb();			[...]
+	 *	atomic_read(&nr_ats_masters);	pci_enable_ats() // writel()
+	 *
+	 * Ensures that we always see the incremented 'nr_ats_masters' count if
+	 * ATS was enabled at the PCI device before completion of the TLBI.
+	 */
+	smp_mb();
+	if (!atomic_read(&smmu_domain->nr_ats_masters))
+		return 0;
+
+	arm_smmu_atc_inv_to_cmd(ssid, iova, size, &cmd);
+
+	spin_lock_irqsave(&smmu_domain->devices_lock, flags);
+	list_for_each_entry(master, &smmu_domain->devices, domain_head) {
+		if (!master->ats_enabled)
+			continue;
+
+		for (i = 0; i < master->num_sids; i++) {
+			cmd.atc.sid = master->sids[i];
+			arm_smmu_cmdq_batch_add(smmu_domain->smmu, &cmds, &cmd);
+		}
+	}
+	spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
+
+	return arm_smmu_cmdq_batch_submit(smmu_domain->smmu, &cmds);
+}
+
+/* IO_PGTABLE API */
+static void arm_smmu_tlb_inv_context(void *cookie)
+{
+	struct arm_smmu_domain *smmu_domain = cookie;
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
+	struct arm_smmu_cmdq_ent cmd;
+
+	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
+		cmd.opcode	= CMDQ_OP_TLBI_NH_ASID;
+		cmd.tlbi.asid	= smmu_domain->s1_cfg.cd.asid;
+		cmd.tlbi.vmid	= 0;
+	} else {
+		cmd.opcode	= CMDQ_OP_TLBI_S12_VMALL;
+		cmd.tlbi.vmid	= smmu_domain->s2_cfg.vmid;
+	}
+
+	/*
+	 * NOTE: when io-pgtable is in non-strict mode, we may get here with
+	 * PTEs previously cleared by unmaps on the current CPU not yet visible
+	 * to the SMMU. We are relying on the dma_wmb() implicit during cmd
+	 * insertion to guarantee those are observed before the TLBI. Do be
+	 * careful, 007.
+	 */
+	arm_smmu_cmdq_issue_cmd(smmu, &cmd);
+	arm_smmu_cmdq_issue_sync(smmu);
+	arm_smmu_atc_inv_domain(smmu_domain, 0, 0, 0);
+}
+
+static void arm_smmu_tlb_inv_range(unsigned long iova, size_t size,
+				   size_t granule, bool leaf,
+				   struct arm_smmu_domain *smmu_domain)
+{
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
+	unsigned long start = iova, end = iova + size, num_pages = 0, tg = 0;
+	size_t inv_range = granule;
+	struct arm_smmu_cmdq_batch cmds = {};
+	struct arm_smmu_cmdq_ent cmd = {
+		.tlbi = {
+			.leaf	= leaf,
+		},
+	};
+
+	if (!size)
+		return;
+
+	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
+		cmd.opcode	= CMDQ_OP_TLBI_NH_VA;
+		cmd.tlbi.asid	= smmu_domain->s1_cfg.cd.asid;
+	} else {
+		cmd.opcode	= CMDQ_OP_TLBI_S2_IPA;
+		cmd.tlbi.vmid	= smmu_domain->s2_cfg.vmid;
+	}
+
+	if (smmu->features & ARM_SMMU_FEAT_RANGE_INV) {
+		/* Get the leaf page size */
+		tg = __ffs(smmu_domain->domain.pgsize_bitmap);
+
+		/* Convert page size of 12,14,16 (log2) to 1,2,3 */
+		cmd.tlbi.tg = (tg - 10) / 2;
+
+		/* Determine what level the granule is at */
+		cmd.tlbi.ttl = 4 - ((ilog2(granule) - 3) / (tg - 3));
+
+		num_pages = size >> tg;
+	}
+
+	while (iova < end) {
+		if (smmu->features & ARM_SMMU_FEAT_RANGE_INV) {
+			/*
+			 * On each iteration of the loop, the range is 5 bits
+			 * worth of the aligned size remaining.
+			 * The range in pages is:
+			 *
+			 * range = (num_pages & (0x1f << __ffs(num_pages)))
+			 */
+			unsigned long scale, num;
+
+			/* Determine the power of 2 multiple number of pages */
+			scale = __ffs(num_pages);
+			cmd.tlbi.scale = scale;
+
+			/* Determine how many chunks of 2^scale size we have */
+			num = (num_pages >> scale) & CMDQ_TLBI_RANGE_NUM_MAX;
+			cmd.tlbi.num = num - 1;
+
+			/* range is num * 2^scale * pgsize */
+			inv_range = num << (scale + tg);
+
+			/* Clear out the lower order bits for the next iteration */
+			num_pages -= num << scale;
+		}
+
+		cmd.tlbi.addr = iova;
+		arm_smmu_cmdq_batch_add(smmu, &cmds, &cmd);
+		iova += inv_range;
+	}
+	arm_smmu_cmdq_batch_submit(smmu, &cmds);
+
+	/*
+	 * Unfortunately, this can't be leaf-only since we may have
+	 * zapped an entire table.
+	 */
+	arm_smmu_atc_inv_domain(smmu_domain, 0, start, size);
+}
+
+static void arm_smmu_tlb_inv_page_nosync(struct iommu_iotlb_gather *gather,
+					 unsigned long iova, size_t granule,
+					 void *cookie)
+{
+	struct arm_smmu_domain *smmu_domain = cookie;
+	struct iommu_domain *domain = &smmu_domain->domain;
+
+	iommu_iotlb_gather_add_page(domain, gather, iova, granule);
+}
+
+static void arm_smmu_tlb_inv_walk(unsigned long iova, size_t size,
+				  size_t granule, void *cookie)
+{
+	arm_smmu_tlb_inv_range(iova, size, granule, false, cookie);
+}
+
+static void arm_smmu_tlb_inv_leaf(unsigned long iova, size_t size,
+				  size_t granule, void *cookie)
+{
+	arm_smmu_tlb_inv_range(iova, size, granule, true, cookie);
+}
+
+static const struct iommu_flush_ops arm_smmu_flush_ops = {
+	.tlb_flush_all	= arm_smmu_tlb_inv_context,
+	.tlb_flush_walk = arm_smmu_tlb_inv_walk,
+	.tlb_flush_leaf = arm_smmu_tlb_inv_leaf,
+	.tlb_add_page	= arm_smmu_tlb_inv_page_nosync,
+};
+
+/* IOMMU API */
+static bool arm_smmu_capable(enum iommu_cap cap)
+{
+	switch (cap) {
+	case IOMMU_CAP_CACHE_COHERENCY:
+		return true;
+	case IOMMU_CAP_NOEXEC:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static struct iommu_domain *arm_smmu_domain_alloc(unsigned type)
+{
+	struct arm_smmu_domain *smmu_domain;
+
+	if (type != IOMMU_DOMAIN_UNMANAGED &&
+	    type != IOMMU_DOMAIN_DMA &&
+	    type != IOMMU_DOMAIN_IDENTITY)
+		return NULL;
+
+	/*
+	 * Allocate the domain and initialise some of its data structures.
+	 * We can't really do anything meaningful until we've added a
+	 * master.
+	 */
+	smmu_domain = kzalloc(sizeof(*smmu_domain), GFP_KERNEL);
+	if (!smmu_domain)
+		return NULL;
+
+	if (type == IOMMU_DOMAIN_DMA &&
+	    iommu_get_dma_cookie(&smmu_domain->domain)) {
+		kfree(smmu_domain);
+		return NULL;
+	}
+
+	mutex_init(&smmu_domain->init_mutex);
+	INIT_LIST_HEAD(&smmu_domain->devices);
+	spin_lock_init(&smmu_domain->devices_lock);
+
+	return &smmu_domain->domain;
+}
+
+static int arm_smmu_bitmap_alloc(unsigned long *map, int span)
+{
+	int idx, size = 1 << span;
+
+	do {
+		idx = find_first_zero_bit(map, size);
+		if (idx == size)
+			return -ENOSPC;
+	} while (test_and_set_bit(idx, map));
+
+	return idx;
+}
+
+static void arm_smmu_bitmap_free(unsigned long *map, int idx)
+{
+	clear_bit(idx, map);
+}
+
+static void arm_smmu_domain_free(struct iommu_domain *domain)
+{
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
+
+	iommu_put_dma_cookie(domain);
+	free_io_pgtable_ops(smmu_domain->pgtbl_ops);
+
+	/* Free the CD and ASID, if we allocated them */
+	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
+		struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
+
+		if (cfg->cdcfg.cdtab)
+			arm_smmu_free_cd_tables(smmu_domain);
+		arm_smmu_free_asid(&cfg->cd);
+	} else {
+		struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
+		if (cfg->vmid)
+			arm_smmu_bitmap_free(smmu->vmid_map, cfg->vmid);
+	}
+
+	kfree(smmu_domain);
+}
+
+static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,
+				       struct arm_smmu_master *master,
+				       struct io_pgtable_cfg *pgtbl_cfg)
+{
+	int ret;
+	u32 asid;
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
+	struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
+	typeof(&pgtbl_cfg->arm_lpae_s1_cfg.tcr) tcr = &pgtbl_cfg->arm_lpae_s1_cfg.tcr;
+
+	ret = xa_alloc(&asid_xa, &asid, &cfg->cd,
+		       XA_LIMIT(1, (1 << smmu->asid_bits) - 1), GFP_KERNEL);
+	if (ret)
+		return ret;
+
+	cfg->s1cdmax = master->ssid_bits;
+
+	ret = arm_smmu_alloc_cd_tables(smmu_domain);
+	if (ret)
+		goto out_free_asid;
+
+	cfg->cd.asid	= (u16)asid;
+	cfg->cd.ttbr	= pgtbl_cfg->arm_lpae_s1_cfg.ttbr;
+	cfg->cd.tcr	= FIELD_PREP(CTXDESC_CD_0_TCR_T0SZ, tcr->tsz) |
+			  FIELD_PREP(CTXDESC_CD_0_TCR_TG0, tcr->tg) |
+			  FIELD_PREP(CTXDESC_CD_0_TCR_IRGN0, tcr->irgn) |
+			  FIELD_PREP(CTXDESC_CD_0_TCR_ORGN0, tcr->orgn) |
+			  FIELD_PREP(CTXDESC_CD_0_TCR_SH0, tcr->sh) |
+			  FIELD_PREP(CTXDESC_CD_0_TCR_IPS, tcr->ips) |
+			  CTXDESC_CD_0_TCR_EPD1 | CTXDESC_CD_0_AA64;
+	cfg->cd.mair	= pgtbl_cfg->arm_lpae_s1_cfg.mair;
+
+	/*
+	 * Note that this will end up calling arm_smmu_sync_cd() before
+	 * the master has been added to the devices list for this domain.
+	 * This isn't an issue because the STE hasn't been installed yet.
+	 */
+	ret = arm_smmu_write_ctx_desc(smmu_domain, 0, &cfg->cd);
+	if (ret)
+		goto out_free_cd_tables;
+
+	return 0;
+
+out_free_cd_tables:
+	arm_smmu_free_cd_tables(smmu_domain);
+out_free_asid:
+	arm_smmu_free_asid(&cfg->cd);
+	return ret;
+}
+
+static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
+				       struct arm_smmu_master *master,
+				       struct io_pgtable_cfg *pgtbl_cfg)
+{
+	int vmid;
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
+	struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
+	typeof(&pgtbl_cfg->arm_lpae_s2_cfg.vtcr) vtcr;
+
+	vmid = arm_smmu_bitmap_alloc(smmu->vmid_map, smmu->vmid_bits);
+	if (vmid < 0)
+		return vmid;
+
+	vtcr = &pgtbl_cfg->arm_lpae_s2_cfg.vtcr;
+	cfg->vmid	= (u16)vmid;
+	cfg->vttbr	= pgtbl_cfg->arm_lpae_s2_cfg.vttbr;
+	cfg->vtcr	= FIELD_PREP(STRTAB_STE_2_VTCR_S2T0SZ, vtcr->tsz) |
+			  FIELD_PREP(STRTAB_STE_2_VTCR_S2SL0, vtcr->sl) |
+			  FIELD_PREP(STRTAB_STE_2_VTCR_S2IR0, vtcr->irgn) |
+			  FIELD_PREP(STRTAB_STE_2_VTCR_S2OR0, vtcr->orgn) |
+			  FIELD_PREP(STRTAB_STE_2_VTCR_S2SH0, vtcr->sh) |
+			  FIELD_PREP(STRTAB_STE_2_VTCR_S2TG, vtcr->tg) |
+			  FIELD_PREP(STRTAB_STE_2_VTCR_S2PS, vtcr->ps);
+	return 0;
+}
+
+static int arm_smmu_domain_finalise(struct iommu_domain *domain,
+				    struct arm_smmu_master *master)
+{
+	int ret;
+	unsigned long ias, oas;
+	enum io_pgtable_fmt fmt;
+	struct io_pgtable_cfg pgtbl_cfg;
+	struct io_pgtable_ops *pgtbl_ops;
+	int (*finalise_stage_fn)(struct arm_smmu_domain *,
+				 struct arm_smmu_master *,
+				 struct io_pgtable_cfg *);
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
+
+	if (domain->type == IOMMU_DOMAIN_IDENTITY) {
+		smmu_domain->stage = ARM_SMMU_DOMAIN_BYPASS;
+		return 0;
+	}
+
+	/* Restrict the stage to what we can actually support */
+	if (!(smmu->features & ARM_SMMU_FEAT_TRANS_S1))
+		smmu_domain->stage = ARM_SMMU_DOMAIN_S2;
+	if (!(smmu->features & ARM_SMMU_FEAT_TRANS_S2))
+		smmu_domain->stage = ARM_SMMU_DOMAIN_S1;
+
+	switch (smmu_domain->stage) {
+	case ARM_SMMU_DOMAIN_S1:
+		ias = (smmu->features & ARM_SMMU_FEAT_VAX) ? 52 : 48;
+		ias = min_t(unsigned long, ias, VA_BITS);
+		oas = smmu->ias;
+		fmt = ARM_64_LPAE_S1;
+		finalise_stage_fn = arm_smmu_domain_finalise_s1;
+		break;
+	case ARM_SMMU_DOMAIN_NESTED:
+	case ARM_SMMU_DOMAIN_S2:
+		ias = smmu->ias;
+		oas = smmu->oas;
+		fmt = ARM_64_LPAE_S2;
+		finalise_stage_fn = arm_smmu_domain_finalise_s2;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	pgtbl_cfg = (struct io_pgtable_cfg) {
+		.pgsize_bitmap	= smmu->pgsize_bitmap,
+		.ias		= ias,
+		.oas		= oas,
+		.coherent_walk	= smmu->features & ARM_SMMU_FEAT_COHERENCY,
+		.tlb		= &arm_smmu_flush_ops,
+		.iommu_dev	= smmu->dev,
+	};
+
+	if (smmu_domain->non_strict)
+		pgtbl_cfg.quirks |= IO_PGTABLE_QUIRK_NON_STRICT;
+
+	pgtbl_ops = alloc_io_pgtable_ops(fmt, &pgtbl_cfg, smmu_domain);
+	if (!pgtbl_ops)
+		return -ENOMEM;
+
+	domain->pgsize_bitmap = pgtbl_cfg.pgsize_bitmap;
+	domain->geometry.aperture_end = (1UL << pgtbl_cfg.ias) - 1;
+	domain->geometry.force_aperture = true;
+
+	ret = finalise_stage_fn(smmu_domain, master, &pgtbl_cfg);
+	if (ret < 0) {
+		free_io_pgtable_ops(pgtbl_ops);
+		return ret;
+	}
+
+	smmu_domain->pgtbl_ops = pgtbl_ops;
+	return 0;
+}
+
+static __le64 *arm_smmu_get_step_for_sid(struct arm_smmu_device *smmu, u32 sid)
+{
+	__le64 *step;
+	struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg;
+
+	if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB) {
+		struct arm_smmu_strtab_l1_desc *l1_desc;
+		int idx;
+
+		/* Two-level walk */
+		idx = (sid >> STRTAB_SPLIT) * STRTAB_L1_DESC_DWORDS;
+		l1_desc = &cfg->l1_desc[idx];
+		idx = (sid & ((1 << STRTAB_SPLIT) - 1)) * STRTAB_STE_DWORDS;
+		step = &l1_desc->l2ptr[idx];
+	} else {
+		/* Simple linear lookup */
+		step = &cfg->strtab[sid * STRTAB_STE_DWORDS];
+	}
+
+	return step;
+}
+
+static void arm_smmu_install_ste_for_dev(struct arm_smmu_master *master)
+{
+	int i, j;
+	struct arm_smmu_device *smmu = master->smmu;
+
+	for (i = 0; i < master->num_sids; ++i) {
+		u32 sid = master->sids[i];
+		__le64 *step = arm_smmu_get_step_for_sid(smmu, sid);
+
+		/* Bridged PCI devices may end up with duplicated IDs */
+		for (j = 0; j < i; j++)
+			if (master->sids[j] == sid)
+				break;
+		if (j < i)
+			continue;
+
+		arm_smmu_write_strtab_ent(master, sid, step);
+	}
+}
+
+static bool arm_smmu_ats_supported(struct arm_smmu_master *master)
+{
+	struct device *dev = master->dev;
+	struct arm_smmu_device *smmu = master->smmu;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+
+	if (!(smmu->features & ARM_SMMU_FEAT_ATS))
+		return false;
+
+	if (!(fwspec->flags & IOMMU_FWSPEC_PCI_RC_ATS))
+		return false;
+
+	return dev_is_pci(dev) && pci_ats_supported(to_pci_dev(dev));
+}
+
+static void arm_smmu_enable_ats(struct arm_smmu_master *master)
+{
+	size_t stu;
+	struct pci_dev *pdev;
+	struct arm_smmu_device *smmu = master->smmu;
+	struct arm_smmu_domain *smmu_domain = master->domain;
+
+	/* Don't enable ATS at the endpoint if it's not enabled in the STE */
+	if (!master->ats_enabled)
+		return;
+
+	/* Smallest Translation Unit: log2 of the smallest supported granule */
+	stu = __ffs(smmu->pgsize_bitmap);
+	pdev = to_pci_dev(master->dev);
+
+	atomic_inc(&smmu_domain->nr_ats_masters);
+	arm_smmu_atc_inv_domain(smmu_domain, 0, 0, 0);
+	if (pci_enable_ats(pdev, stu))
+		dev_err(master->dev, "Failed to enable ATS (STU %zu)\n", stu);
+}
+
+static void arm_smmu_disable_ats(struct arm_smmu_master *master)
+{
+	struct arm_smmu_domain *smmu_domain = master->domain;
+
+	if (!master->ats_enabled)
+		return;
+
+	pci_disable_ats(to_pci_dev(master->dev));
+	/*
+	 * Ensure ATS is disabled at the endpoint before we issue the
+	 * ATC invalidation via the SMMU.
+	 */
+	wmb();
+	arm_smmu_atc_inv_master(master);
+	atomic_dec(&smmu_domain->nr_ats_masters);
+}
+
+static int arm_smmu_enable_pasid(struct arm_smmu_master *master)
+{
+	int ret;
+	int features;
+	int num_pasids;
+	struct pci_dev *pdev;
+
+	if (!dev_is_pci(master->dev))
+		return -ENODEV;
+
+	pdev = to_pci_dev(master->dev);
+
+	features = pci_pasid_features(pdev);
+	if (features < 0)
+		return features;
+
+	num_pasids = pci_max_pasids(pdev);
+	if (num_pasids <= 0)
+		return num_pasids;
+
+	ret = pci_enable_pasid(pdev, features);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to enable PASID\n");
+		return ret;
+	}
+
+	master->ssid_bits = min_t(u8, ilog2(num_pasids),
+				  master->smmu->ssid_bits);
+	return 0;
+}
+
+static void arm_smmu_disable_pasid(struct arm_smmu_master *master)
+{
+	struct pci_dev *pdev;
+
+	if (!dev_is_pci(master->dev))
+		return;
+
+	pdev = to_pci_dev(master->dev);
+
+	if (!pdev->pasid_enabled)
+		return;
+
+	master->ssid_bits = 0;
+	pci_disable_pasid(pdev);
+}
+
+static void arm_smmu_detach_dev(struct arm_smmu_master *master)
+{
+	unsigned long flags;
+	struct arm_smmu_domain *smmu_domain = master->domain;
+
+	if (!smmu_domain)
+		return;
+
+	arm_smmu_disable_ats(master);
+
+	spin_lock_irqsave(&smmu_domain->devices_lock, flags);
+	list_del(&master->domain_head);
+	spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
+
+	master->domain = NULL;
+	master->ats_enabled = false;
+	arm_smmu_install_ste_for_dev(master);
+}
+
+static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
+{
+	int ret = 0;
+	unsigned long flags;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+	struct arm_smmu_device *smmu;
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+	struct arm_smmu_master *master;
+
+	if (!fwspec)
+		return -ENOENT;
+
+	master = dev_iommu_priv_get(dev);
+	smmu = master->smmu;
+
+	arm_smmu_detach_dev(master);
+
+	mutex_lock(&smmu_domain->init_mutex);
+
+	if (!smmu_domain->smmu) {
+		smmu_domain->smmu = smmu;
+		ret = arm_smmu_domain_finalise(domain, master);
+		if (ret) {
+			smmu_domain->smmu = NULL;
+			goto out_unlock;
+		}
+	} else if (smmu_domain->smmu != smmu) {
+		dev_err(dev,
+			"cannot attach to SMMU %s (upstream of %s)\n",
+			dev_name(smmu_domain->smmu->dev),
+			dev_name(smmu->dev));
+		ret = -ENXIO;
+		goto out_unlock;
+	} else if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1 &&
+		   master->ssid_bits != smmu_domain->s1_cfg.s1cdmax) {
+		dev_err(dev,
+			"cannot attach to incompatible domain (%u SSID bits != %u)\n",
+			smmu_domain->s1_cfg.s1cdmax, master->ssid_bits);
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	master->domain = smmu_domain;
+
+	if (smmu_domain->stage != ARM_SMMU_DOMAIN_BYPASS)
+		master->ats_enabled = arm_smmu_ats_supported(master);
+
+	arm_smmu_install_ste_for_dev(master);
+
+	spin_lock_irqsave(&smmu_domain->devices_lock, flags);
+	list_add(&master->domain_head, &smmu_domain->devices);
+	spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
+
+	arm_smmu_enable_ats(master);
+
+out_unlock:
+	mutex_unlock(&smmu_domain->init_mutex);
+	return ret;
+}
+
+static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova,
+			phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
+{
+	struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops;
+
+	if (!ops)
+		return -ENODEV;
+
+	return ops->map(ops, iova, paddr, size, prot);
+}
+
+static size_t arm_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
+			     size_t size, struct iommu_iotlb_gather *gather)
+{
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+	struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops;
+
+	if (!ops)
+		return 0;
+
+	return ops->unmap(ops, iova, size, gather);
+}
+
+static void arm_smmu_flush_iotlb_all(struct iommu_domain *domain)
+{
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+
+	if (smmu_domain->smmu)
+		arm_smmu_tlb_inv_context(smmu_domain);
+}
+
+static void arm_smmu_iotlb_sync(struct iommu_domain *domain,
+				struct iommu_iotlb_gather *gather)
+{
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+
+	arm_smmu_tlb_inv_range(gather->start, gather->end - gather->start,
+			       gather->pgsize, true, smmu_domain);
+}
+
+static phys_addr_t
+arm_smmu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
+{
+	struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops;
+
+	if (domain->type == IOMMU_DOMAIN_IDENTITY)
+		return iova;
+
+	if (!ops)
+		return 0;
+
+	return ops->iova_to_phys(ops, iova);
+}
+
+static struct platform_driver arm_smmu_driver;
+
+static
+struct arm_smmu_device *arm_smmu_get_by_fwnode(struct fwnode_handle *fwnode)
+{
+	struct device *dev = driver_find_device_by_fwnode(&arm_smmu_driver.driver,
+							  fwnode);
+	put_device(dev);
+	return dev ? dev_get_drvdata(dev) : NULL;
+}
+
+static bool arm_smmu_sid_in_range(struct arm_smmu_device *smmu, u32 sid)
+{
+	unsigned long limit = smmu->strtab_cfg.num_l1_ents;
+
+	if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB)
+		limit *= 1UL << STRTAB_SPLIT;
+
+	return sid < limit;
+}
+
+static struct iommu_ops arm_smmu_ops;
+
+static struct iommu_device *arm_smmu_probe_device(struct device *dev)
+{
+	int i, ret;
+	struct arm_smmu_device *smmu;
+	struct arm_smmu_master *master;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+
+	if (!fwspec || fwspec->ops != &arm_smmu_ops)
+		return ERR_PTR(-ENODEV);
+
+	if (WARN_ON_ONCE(dev_iommu_priv_get(dev)))
+		return ERR_PTR(-EBUSY);
+
+	smmu = arm_smmu_get_by_fwnode(fwspec->iommu_fwnode);
+	if (!smmu)
+		return ERR_PTR(-ENODEV);
+
+	master = kzalloc(sizeof(*master), GFP_KERNEL);
+	if (!master)
+		return ERR_PTR(-ENOMEM);
+
+	master->dev = dev;
+	master->smmu = smmu;
+	master->sids = fwspec->ids;
+	master->num_sids = fwspec->num_ids;
+	dev_iommu_priv_set(dev, master);
+
+	/* Check the SIDs are in range of the SMMU and our stream table */
+	for (i = 0; i < master->num_sids; i++) {
+		u32 sid = master->sids[i];
+
+		if (!arm_smmu_sid_in_range(smmu, sid)) {
+			ret = -ERANGE;
+			goto err_free_master;
+		}
+
+		/* Ensure l2 strtab is initialised */
+		if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB) {
+			ret = arm_smmu_init_l2_strtab(smmu, sid);
+			if (ret)
+				goto err_free_master;
+		}
+	}
+
+	master->ssid_bits = min(smmu->ssid_bits, fwspec->num_pasid_bits);
+
+	/*
+	 * Note that PASID must be enabled before, and disabled after ATS:
+	 * PCI Express Base 4.0r1.0 - 10.5.1.3 ATS Control Register
+	 *
+	 *   Behavior is undefined if this bit is Set and the value of the PASID
+	 *   Enable, Execute Requested Enable, or Privileged Mode Requested bits
+	 *   are changed.
+	 */
+	arm_smmu_enable_pasid(master);
+
+	if (!(smmu->features & ARM_SMMU_FEAT_2_LVL_CDTAB))
+		master->ssid_bits = min_t(u8, master->ssid_bits,
+					  CTXDESC_LINEAR_CDMAX);
+
+	return &smmu->iommu;
+
+err_free_master:
+	kfree(master);
+	dev_iommu_priv_set(dev, NULL);
+	return ERR_PTR(ret);
+}
+
+static void arm_smmu_release_device(struct device *dev)
+{
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+	struct arm_smmu_master *master;
+
+	if (!fwspec || fwspec->ops != &arm_smmu_ops)
+		return;
+
+	master = dev_iommu_priv_get(dev);
+	arm_smmu_detach_dev(master);
+	arm_smmu_disable_pasid(master);
+	kfree(master);
+	iommu_fwspec_free(dev);
+}
+
+static struct iommu_group *arm_smmu_device_group(struct device *dev)
+{
+	struct iommu_group *group;
+
+	/*
+	 * We don't support devices sharing stream IDs other than PCI RID
+	 * aliases, since the necessary ID-to-device lookup becomes rather
+	 * impractical given a potential sparse 32-bit stream ID space.
+	 */
+	if (dev_is_pci(dev))
+		group = pci_device_group(dev);
+	else
+		group = generic_device_group(dev);
+
+	return group;
+}
+
+static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
+				    enum iommu_attr attr, void *data)
+{
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+
+	switch (domain->type) {
+	case IOMMU_DOMAIN_UNMANAGED:
+		switch (attr) {
+		case DOMAIN_ATTR_NESTING:
+			*(int *)data = (smmu_domain->stage == ARM_SMMU_DOMAIN_NESTED);
+			return 0;
+		default:
+			return -ENODEV;
+		}
+		break;
+	case IOMMU_DOMAIN_DMA:
+		switch (attr) {
+		case DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE:
+			*(int *)data = smmu_domain->non_strict;
+			return 0;
+		default:
+			return -ENODEV;
+		}
+		break;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int arm_smmu_domain_set_attr(struct iommu_domain *domain,
+				    enum iommu_attr attr, void *data)
+{
+	int ret = 0;
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+
+	mutex_lock(&smmu_domain->init_mutex);
+
+	switch (domain->type) {
+	case IOMMU_DOMAIN_UNMANAGED:
+		switch (attr) {
+		case DOMAIN_ATTR_NESTING:
+			if (smmu_domain->smmu) {
+				ret = -EPERM;
+				goto out_unlock;
+			}
+
+			if (*(int *)data)
+				smmu_domain->stage = ARM_SMMU_DOMAIN_NESTED;
+			else
+				smmu_domain->stage = ARM_SMMU_DOMAIN_S1;
+			break;
+		default:
+			ret = -ENODEV;
+		}
+		break;
+	case IOMMU_DOMAIN_DMA:
+		switch(attr) {
+		case DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE:
+			smmu_domain->non_strict = *(int *)data;
+			break;
+		default:
+			ret = -ENODEV;
+		}
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+out_unlock:
+	mutex_unlock(&smmu_domain->init_mutex);
+	return ret;
+}
+
+static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args)
+{
+	return iommu_fwspec_add_ids(dev, args->args, 1);
+}
+
+static void arm_smmu_get_resv_regions(struct device *dev,
+				      struct list_head *head)
+{
+	struct iommu_resv_region *region;
+	int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO;
+
+	region = iommu_alloc_resv_region(MSI_IOVA_BASE, MSI_IOVA_LENGTH,
+					 prot, IOMMU_RESV_SW_MSI);
+	if (!region)
+		return;
+
+	list_add_tail(&region->list, head);
+
+	iommu_dma_get_resv_regions(dev, head);
+}
+
+static struct iommu_ops arm_smmu_ops = {
+	.capable		= arm_smmu_capable,
+	.domain_alloc		= arm_smmu_domain_alloc,
+	.domain_free		= arm_smmu_domain_free,
+	.attach_dev		= arm_smmu_attach_dev,
+	.map			= arm_smmu_map,
+	.unmap			= arm_smmu_unmap,
+	.flush_iotlb_all	= arm_smmu_flush_iotlb_all,
+	.iotlb_sync		= arm_smmu_iotlb_sync,
+	.iova_to_phys		= arm_smmu_iova_to_phys,
+	.probe_device		= arm_smmu_probe_device,
+	.release_device		= arm_smmu_release_device,
+	.device_group		= arm_smmu_device_group,
+	.domain_get_attr	= arm_smmu_domain_get_attr,
+	.domain_set_attr	= arm_smmu_domain_set_attr,
+	.of_xlate		= arm_smmu_of_xlate,
+	.get_resv_regions	= arm_smmu_get_resv_regions,
+	.put_resv_regions	= generic_iommu_put_resv_regions,
+	.pgsize_bitmap		= -1UL, /* Restricted during device attach */
+};
+
+/* Probing and initialisation functions */
+static int arm_smmu_init_one_queue(struct arm_smmu_device *smmu,
+				   struct arm_smmu_queue *q,
+				   unsigned long prod_off,
+				   unsigned long cons_off,
+				   size_t dwords, const char *name)
+{
+	size_t qsz;
+
+	do {
+		qsz = ((1 << q->llq.max_n_shift) * dwords) << 3;
+		q->base = dmam_alloc_coherent(smmu->dev, qsz, &q->base_dma,
+					      GFP_KERNEL);
+		if (q->base || qsz < PAGE_SIZE)
+			break;
+
+		q->llq.max_n_shift--;
+	} while (1);
+
+	if (!q->base) {
+		dev_err(smmu->dev,
+			"failed to allocate queue (0x%zx bytes) for %s\n",
+			qsz, name);
+		return -ENOMEM;
+	}
+
+	if (!WARN_ON(q->base_dma & (qsz - 1))) {
+		dev_info(smmu->dev, "allocated %u entries for %s\n",
+			 1 << q->llq.max_n_shift, name);
+	}
+
+	q->prod_reg	= arm_smmu_page1_fixup(prod_off, smmu);
+	q->cons_reg	= arm_smmu_page1_fixup(cons_off, smmu);
+	q->ent_dwords	= dwords;
+
+	q->q_base  = Q_BASE_RWA;
+	q->q_base |= q->base_dma & Q_BASE_ADDR_MASK;
+	q->q_base |= FIELD_PREP(Q_BASE_LOG2SIZE, q->llq.max_n_shift);
+
+	q->llq.prod = q->llq.cons = 0;
+	return 0;
+}
+
+static void arm_smmu_cmdq_free_bitmap(void *data)
+{
+	unsigned long *bitmap = data;
+	bitmap_free(bitmap);
+}
+
+static int arm_smmu_cmdq_init(struct arm_smmu_device *smmu)
+{
+	int ret = 0;
+	struct arm_smmu_cmdq *cmdq = &smmu->cmdq;
+	unsigned int nents = 1 << cmdq->q.llq.max_n_shift;
+	atomic_long_t *bitmap;
+
+	atomic_set(&cmdq->owner_prod, 0);
+	atomic_set(&cmdq->lock, 0);
+
+	bitmap = (atomic_long_t *)bitmap_zalloc(nents, GFP_KERNEL);
+	if (!bitmap) {
+		dev_err(smmu->dev, "failed to allocate cmdq bitmap\n");
+		ret = -ENOMEM;
+	} else {
+		cmdq->valid_map = bitmap;
+		devm_add_action(smmu->dev, arm_smmu_cmdq_free_bitmap, bitmap);
+	}
+
+	return ret;
+}
+
+static int arm_smmu_init_queues(struct arm_smmu_device *smmu)
+{
+	int ret;
+
+	/* cmdq */
+	ret = arm_smmu_init_one_queue(smmu, &smmu->cmdq.q, ARM_SMMU_CMDQ_PROD,
+				      ARM_SMMU_CMDQ_CONS, CMDQ_ENT_DWORDS,
+				      "cmdq");
+	if (ret)
+		return ret;
+
+	ret = arm_smmu_cmdq_init(smmu);
+	if (ret)
+		return ret;
+
+	/* evtq */
+	ret = arm_smmu_init_one_queue(smmu, &smmu->evtq.q, ARM_SMMU_EVTQ_PROD,
+				      ARM_SMMU_EVTQ_CONS, EVTQ_ENT_DWORDS,
+				      "evtq");
+	if (ret)
+		return ret;
+
+	/* priq */
+	if (!(smmu->features & ARM_SMMU_FEAT_PRI))
+		return 0;
+
+	return arm_smmu_init_one_queue(smmu, &smmu->priq.q, ARM_SMMU_PRIQ_PROD,
+				       ARM_SMMU_PRIQ_CONS, PRIQ_ENT_DWORDS,
+				       "priq");
+}
+
+static int arm_smmu_init_l1_strtab(struct arm_smmu_device *smmu)
+{
+	unsigned int i;
+	struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg;
+	size_t size = sizeof(*cfg->l1_desc) * cfg->num_l1_ents;
+	void *strtab = smmu->strtab_cfg.strtab;
+
+	cfg->l1_desc = devm_kzalloc(smmu->dev, size, GFP_KERNEL);
+	if (!cfg->l1_desc) {
+		dev_err(smmu->dev, "failed to allocate l1 stream table desc\n");
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < cfg->num_l1_ents; ++i) {
+		arm_smmu_write_strtab_l1_desc(strtab, &cfg->l1_desc[i]);
+		strtab += STRTAB_L1_DESC_DWORDS << 3;
+	}
+
+	return 0;
+}
+
+static int arm_smmu_init_strtab_2lvl(struct arm_smmu_device *smmu)
+{
+	void *strtab;
+	u64 reg;
+	u32 size, l1size;
+	struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg;
+
+	/* Calculate the L1 size, capped to the SIDSIZE. */
+	size = STRTAB_L1_SZ_SHIFT - (ilog2(STRTAB_L1_DESC_DWORDS) + 3);
+	size = min(size, smmu->sid_bits - STRTAB_SPLIT);
+	cfg->num_l1_ents = 1 << size;
+
+	size += STRTAB_SPLIT;
+	if (size < smmu->sid_bits)
+		dev_warn(smmu->dev,
+			 "2-level strtab only covers %u/%u bits of SID\n",
+			 size, smmu->sid_bits);
+
+	l1size = cfg->num_l1_ents * (STRTAB_L1_DESC_DWORDS << 3);
+	strtab = dmam_alloc_coherent(smmu->dev, l1size, &cfg->strtab_dma,
+				     GFP_KERNEL);
+	if (!strtab) {
+		dev_err(smmu->dev,
+			"failed to allocate l1 stream table (%u bytes)\n",
+			size);
+		return -ENOMEM;
+	}
+	cfg->strtab = strtab;
+
+	/* Configure strtab_base_cfg for 2 levels */
+	reg  = FIELD_PREP(STRTAB_BASE_CFG_FMT, STRTAB_BASE_CFG_FMT_2LVL);
+	reg |= FIELD_PREP(STRTAB_BASE_CFG_LOG2SIZE, size);
+	reg |= FIELD_PREP(STRTAB_BASE_CFG_SPLIT, STRTAB_SPLIT);
+	cfg->strtab_base_cfg = reg;
+
+	return arm_smmu_init_l1_strtab(smmu);
+}
+
+static int arm_smmu_init_strtab_linear(struct arm_smmu_device *smmu)
+{
+	void *strtab;
+	u64 reg;
+	u32 size;
+	struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg;
+
+	size = (1 << smmu->sid_bits) * (STRTAB_STE_DWORDS << 3);
+	strtab = dmam_alloc_coherent(smmu->dev, size, &cfg->strtab_dma,
+				     GFP_KERNEL);
+	if (!strtab) {
+		dev_err(smmu->dev,
+			"failed to allocate linear stream table (%u bytes)\n",
+			size);
+		return -ENOMEM;
+	}
+	cfg->strtab = strtab;
+	cfg->num_l1_ents = 1 << smmu->sid_bits;
+
+	/* Configure strtab_base_cfg for a linear table covering all SIDs */
+	reg  = FIELD_PREP(STRTAB_BASE_CFG_FMT, STRTAB_BASE_CFG_FMT_LINEAR);
+	reg |= FIELD_PREP(STRTAB_BASE_CFG_LOG2SIZE, smmu->sid_bits);
+	cfg->strtab_base_cfg = reg;
+
+	arm_smmu_init_bypass_stes(strtab, cfg->num_l1_ents);
+	return 0;
+}
+
+static int arm_smmu_init_strtab(struct arm_smmu_device *smmu)
+{
+	u64 reg;
+	int ret;
+
+	if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB)
+		ret = arm_smmu_init_strtab_2lvl(smmu);
+	else
+		ret = arm_smmu_init_strtab_linear(smmu);
+
+	if (ret)
+		return ret;
+
+	/* Set the strtab base address */
+	reg  = smmu->strtab_cfg.strtab_dma & STRTAB_BASE_ADDR_MASK;
+	reg |= STRTAB_BASE_RA;
+	smmu->strtab_cfg.strtab_base = reg;
+
+	/* Allocate the first VMID for stage-2 bypass STEs */
+	set_bit(0, smmu->vmid_map);
+	return 0;
+}
+
+static int arm_smmu_init_structures(struct arm_smmu_device *smmu)
+{
+	int ret;
+
+	ret = arm_smmu_init_queues(smmu);
+	if (ret)
+		return ret;
+
+	return arm_smmu_init_strtab(smmu);
+}
+
+static int arm_smmu_write_reg_sync(struct arm_smmu_device *smmu, u32 val,
+				   unsigned int reg_off, unsigned int ack_off)
+{
+	u32 reg;
+
+	writel_relaxed(val, smmu->base + reg_off);
+	return readl_relaxed_poll_timeout(smmu->base + ack_off, reg, reg == val,
+					  1, ARM_SMMU_POLL_TIMEOUT_US);
+}
+
+/* GBPA is "special" */
+static int arm_smmu_update_gbpa(struct arm_smmu_device *smmu, u32 set, u32 clr)
+{
+	int ret;
+	u32 reg, __iomem *gbpa = smmu->base + ARM_SMMU_GBPA;
+
+	ret = readl_relaxed_poll_timeout(gbpa, reg, !(reg & GBPA_UPDATE),
+					 1, ARM_SMMU_POLL_TIMEOUT_US);
+	if (ret)
+		return ret;
+
+	reg &= ~clr;
+	reg |= set;
+	writel_relaxed(reg | GBPA_UPDATE, gbpa);
+	ret = readl_relaxed_poll_timeout(gbpa, reg, !(reg & GBPA_UPDATE),
+					 1, ARM_SMMU_POLL_TIMEOUT_US);
+
+	if (ret)
+		dev_err(smmu->dev, "GBPA not responding to update\n");
+	return ret;
+}
+
+static void arm_smmu_free_msis(void *data)
+{
+	struct device *dev = data;
+	platform_msi_domain_free_irqs(dev);
+}
+
+static void arm_smmu_write_msi_msg(struct msi_desc *desc, struct msi_msg *msg)
+{
+	phys_addr_t doorbell;
+	struct device *dev = msi_desc_to_dev(desc);
+	struct arm_smmu_device *smmu = dev_get_drvdata(dev);
+	phys_addr_t *cfg = arm_smmu_msi_cfg[desc->platform.msi_index];
+
+	doorbell = (((u64)msg->address_hi) << 32) | msg->address_lo;
+	doorbell &= MSI_CFG0_ADDR_MASK;
+
+	writeq_relaxed(doorbell, smmu->base + cfg[0]);
+	writel_relaxed(msg->data, smmu->base + cfg[1]);
+	writel_relaxed(ARM_SMMU_MEMATTR_DEVICE_nGnRE, smmu->base + cfg[2]);
+}
+
+static void arm_smmu_setup_msis(struct arm_smmu_device *smmu)
+{
+	struct msi_desc *desc;
+	int ret, nvec = ARM_SMMU_MAX_MSIS;
+	struct device *dev = smmu->dev;
+
+	/* Clear the MSI address regs */
+	writeq_relaxed(0, smmu->base + ARM_SMMU_GERROR_IRQ_CFG0);
+	writeq_relaxed(0, smmu->base + ARM_SMMU_EVTQ_IRQ_CFG0);
+
+	if (smmu->features & ARM_SMMU_FEAT_PRI)
+		writeq_relaxed(0, smmu->base + ARM_SMMU_PRIQ_IRQ_CFG0);
+	else
+		nvec--;
+
+	if (!(smmu->features & ARM_SMMU_FEAT_MSI))
+		return;
+
+	if (!dev->msi_domain) {
+		dev_info(smmu->dev, "msi_domain absent - falling back to wired irqs\n");
+		return;
+	}
+
+	/* Allocate MSIs for evtq, gerror and priq. Ignore cmdq */
+	ret = platform_msi_domain_alloc_irqs(dev, nvec, arm_smmu_write_msi_msg);
+	if (ret) {
+		dev_warn(dev, "failed to allocate MSIs - falling back to wired irqs\n");
+		return;
+	}
+
+	for_each_msi_entry(desc, dev) {
+		switch (desc->platform.msi_index) {
+		case EVTQ_MSI_INDEX:
+			smmu->evtq.q.irq = desc->irq;
+			break;
+		case GERROR_MSI_INDEX:
+			smmu->gerr_irq = desc->irq;
+			break;
+		case PRIQ_MSI_INDEX:
+			smmu->priq.q.irq = desc->irq;
+			break;
+		default:	/* Unknown */
+			continue;
+		}
+	}
+
+	/* Add callback to free MSIs on teardown */
+	devm_add_action(dev, arm_smmu_free_msis, dev);
+}
+
+static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
+{
+	int irq, ret;
+
+	arm_smmu_setup_msis(smmu);
+
+	/* Request interrupt lines */
+	irq = smmu->evtq.q.irq;
+	if (irq) {
+		ret = devm_request_threaded_irq(smmu->dev, irq, NULL,
+						arm_smmu_evtq_thread,
+						IRQF_ONESHOT,
+						"arm-smmu-v3-evtq", smmu);
+		if (ret < 0)
+			dev_warn(smmu->dev, "failed to enable evtq irq\n");
+	} else {
+		dev_warn(smmu->dev, "no evtq irq - events will not be reported!\n");
+	}
+
+	irq = smmu->gerr_irq;
+	if (irq) {
+		ret = devm_request_irq(smmu->dev, irq, arm_smmu_gerror_handler,
+				       0, "arm-smmu-v3-gerror", smmu);
+		if (ret < 0)
+			dev_warn(smmu->dev, "failed to enable gerror irq\n");
+	} else {
+		dev_warn(smmu->dev, "no gerr irq - errors will not be reported!\n");
+	}
+
+	if (smmu->features & ARM_SMMU_FEAT_PRI) {
+		irq = smmu->priq.q.irq;
+		if (irq) {
+			ret = devm_request_threaded_irq(smmu->dev, irq, NULL,
+							arm_smmu_priq_thread,
+							IRQF_ONESHOT,
+							"arm-smmu-v3-priq",
+							smmu);
+			if (ret < 0)
+				dev_warn(smmu->dev,
+					 "failed to enable priq irq\n");
+		} else {
+			dev_warn(smmu->dev, "no priq irq - PRI will be broken\n");
+		}
+	}
+}
+
+static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
+{
+	int ret, irq;
+	u32 irqen_flags = IRQ_CTRL_EVTQ_IRQEN | IRQ_CTRL_GERROR_IRQEN;
+
+	/* Disable IRQs first */
+	ret = arm_smmu_write_reg_sync(smmu, 0, ARM_SMMU_IRQ_CTRL,
+				      ARM_SMMU_IRQ_CTRLACK);
+	if (ret) {
+		dev_err(smmu->dev, "failed to disable irqs\n");
+		return ret;
+	}
+
+	irq = smmu->combined_irq;
+	if (irq) {
+		/*
+		 * Cavium ThunderX2 implementation doesn't support unique irq
+		 * lines. Use a single irq line for all the SMMUv3 interrupts.
+		 */
+		ret = devm_request_threaded_irq(smmu->dev, irq,
+					arm_smmu_combined_irq_handler,
+					arm_smmu_combined_irq_thread,
+					IRQF_ONESHOT,
+					"arm-smmu-v3-combined-irq", smmu);
+		if (ret < 0)
+			dev_warn(smmu->dev, "failed to enable combined irq\n");
+	} else
+		arm_smmu_setup_unique_irqs(smmu);
+
+	if (smmu->features & ARM_SMMU_FEAT_PRI)
+		irqen_flags |= IRQ_CTRL_PRIQ_IRQEN;
+
+	/* Enable interrupt generation on the SMMU */
+	ret = arm_smmu_write_reg_sync(smmu, irqen_flags,
+				      ARM_SMMU_IRQ_CTRL, ARM_SMMU_IRQ_CTRLACK);
+	if (ret)
+		dev_warn(smmu->dev, "failed to enable irqs\n");
+
+	return 0;
+}
+
+static int arm_smmu_device_disable(struct arm_smmu_device *smmu)
+{
+	int ret;
+
+	ret = arm_smmu_write_reg_sync(smmu, 0, ARM_SMMU_CR0, ARM_SMMU_CR0ACK);
+	if (ret)
+		dev_err(smmu->dev, "failed to clear cr0\n");
+
+	return ret;
+}
+
+static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
+{
+	int ret;
+	u32 reg, enables;
+	struct arm_smmu_cmdq_ent cmd;
+
+	/* Clear CR0 and sync (disables SMMU and queue processing) */
+	reg = readl_relaxed(smmu->base + ARM_SMMU_CR0);
+	if (reg & CR0_SMMUEN) {
+		dev_warn(smmu->dev, "SMMU currently enabled! Resetting...\n");
+		WARN_ON(is_kdump_kernel() && !disable_bypass);
+		arm_smmu_update_gbpa(smmu, GBPA_ABORT, 0);
+	}
+
+	ret = arm_smmu_device_disable(smmu);
+	if (ret)
+		return ret;
+
+	/* CR1 (table and queue memory attributes) */
+	reg = FIELD_PREP(CR1_TABLE_SH, ARM_SMMU_SH_ISH) |
+	      FIELD_PREP(CR1_TABLE_OC, CR1_CACHE_WB) |
+	      FIELD_PREP(CR1_TABLE_IC, CR1_CACHE_WB) |
+	      FIELD_PREP(CR1_QUEUE_SH, ARM_SMMU_SH_ISH) |
+	      FIELD_PREP(CR1_QUEUE_OC, CR1_CACHE_WB) |
+	      FIELD_PREP(CR1_QUEUE_IC, CR1_CACHE_WB);
+	writel_relaxed(reg, smmu->base + ARM_SMMU_CR1);
+
+	/* CR2 (random crap) */
+	reg = CR2_PTM | CR2_RECINVSID | CR2_E2H;
+	writel_relaxed(reg, smmu->base + ARM_SMMU_CR2);
+
+	/* Stream table */
+	writeq_relaxed(smmu->strtab_cfg.strtab_base,
+		       smmu->base + ARM_SMMU_STRTAB_BASE);
+	writel_relaxed(smmu->strtab_cfg.strtab_base_cfg,
+		       smmu->base + ARM_SMMU_STRTAB_BASE_CFG);
+
+	/* Command queue */
+	writeq_relaxed(smmu->cmdq.q.q_base, smmu->base + ARM_SMMU_CMDQ_BASE);
+	writel_relaxed(smmu->cmdq.q.llq.prod, smmu->base + ARM_SMMU_CMDQ_PROD);
+	writel_relaxed(smmu->cmdq.q.llq.cons, smmu->base + ARM_SMMU_CMDQ_CONS);
+
+	enables = CR0_CMDQEN;
+	ret = arm_smmu_write_reg_sync(smmu, enables, ARM_SMMU_CR0,
+				      ARM_SMMU_CR0ACK);
+	if (ret) {
+		dev_err(smmu->dev, "failed to enable command queue\n");
+		return ret;
+	}
+
+	/* Invalidate any cached configuration */
+	cmd.opcode = CMDQ_OP_CFGI_ALL;
+	arm_smmu_cmdq_issue_cmd(smmu, &cmd);
+	arm_smmu_cmdq_issue_sync(smmu);
+
+	/* Invalidate any stale TLB entries */
+	if (smmu->features & ARM_SMMU_FEAT_HYP) {
+		cmd.opcode = CMDQ_OP_TLBI_EL2_ALL;
+		arm_smmu_cmdq_issue_cmd(smmu, &cmd);
+	}
+
+	cmd.opcode = CMDQ_OP_TLBI_NSNH_ALL;
+	arm_smmu_cmdq_issue_cmd(smmu, &cmd);
+	arm_smmu_cmdq_issue_sync(smmu);
+
+	/* Event queue */
+	writeq_relaxed(smmu->evtq.q.q_base, smmu->base + ARM_SMMU_EVTQ_BASE);
+	writel_relaxed(smmu->evtq.q.llq.prod,
+		       arm_smmu_page1_fixup(ARM_SMMU_EVTQ_PROD, smmu));
+	writel_relaxed(smmu->evtq.q.llq.cons,
+		       arm_smmu_page1_fixup(ARM_SMMU_EVTQ_CONS, smmu));
+
+	enables |= CR0_EVTQEN;
+	ret = arm_smmu_write_reg_sync(smmu, enables, ARM_SMMU_CR0,
+				      ARM_SMMU_CR0ACK);
+	if (ret) {
+		dev_err(smmu->dev, "failed to enable event queue\n");
+		return ret;
+	}
+
+	/* PRI queue */
+	if (smmu->features & ARM_SMMU_FEAT_PRI) {
+		writeq_relaxed(smmu->priq.q.q_base,
+			       smmu->base + ARM_SMMU_PRIQ_BASE);
+		writel_relaxed(smmu->priq.q.llq.prod,
+			       arm_smmu_page1_fixup(ARM_SMMU_PRIQ_PROD, smmu));
+		writel_relaxed(smmu->priq.q.llq.cons,
+			       arm_smmu_page1_fixup(ARM_SMMU_PRIQ_CONS, smmu));
+
+		enables |= CR0_PRIQEN;
+		ret = arm_smmu_write_reg_sync(smmu, enables, ARM_SMMU_CR0,
+					      ARM_SMMU_CR0ACK);
+		if (ret) {
+			dev_err(smmu->dev, "failed to enable PRI queue\n");
+			return ret;
+		}
+	}
+
+	if (smmu->features & ARM_SMMU_FEAT_ATS) {
+		enables |= CR0_ATSCHK;
+		ret = arm_smmu_write_reg_sync(smmu, enables, ARM_SMMU_CR0,
+					      ARM_SMMU_CR0ACK);
+		if (ret) {
+			dev_err(smmu->dev, "failed to enable ATS check\n");
+			return ret;
+		}
+	}
+
+	ret = arm_smmu_setup_irqs(smmu);
+	if (ret) {
+		dev_err(smmu->dev, "failed to setup irqs\n");
+		return ret;
+	}
+
+	if (is_kdump_kernel())
+		enables &= ~(CR0_EVTQEN | CR0_PRIQEN);
+
+	/* Enable the SMMU interface, or ensure bypass */
+	if (!bypass || disable_bypass) {
+		enables |= CR0_SMMUEN;
+	} else {
+		ret = arm_smmu_update_gbpa(smmu, 0, GBPA_ABORT);
+		if (ret)
+			return ret;
+	}
+	ret = arm_smmu_write_reg_sync(smmu, enables, ARM_SMMU_CR0,
+				      ARM_SMMU_CR0ACK);
+	if (ret) {
+		dev_err(smmu->dev, "failed to enable SMMU interface\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
+{
+	u32 reg;
+	bool coherent = smmu->features & ARM_SMMU_FEAT_COHERENCY;
+
+	/* IDR0 */
+	reg = readl_relaxed(smmu->base + ARM_SMMU_IDR0);
+
+	/* 2-level structures */
+	if (FIELD_GET(IDR0_ST_LVL, reg) == IDR0_ST_LVL_2LVL)
+		smmu->features |= ARM_SMMU_FEAT_2_LVL_STRTAB;
+
+	if (reg & IDR0_CD2L)
+		smmu->features |= ARM_SMMU_FEAT_2_LVL_CDTAB;
+
+	/*
+	 * Translation table endianness.
+	 * We currently require the same endianness as the CPU, but this
+	 * could be changed later by adding a new IO_PGTABLE_QUIRK.
+	 */
+	switch (FIELD_GET(IDR0_TTENDIAN, reg)) {
+	case IDR0_TTENDIAN_MIXED:
+		smmu->features |= ARM_SMMU_FEAT_TT_LE | ARM_SMMU_FEAT_TT_BE;
+		break;
+#ifdef __BIG_ENDIAN
+	case IDR0_TTENDIAN_BE:
+		smmu->features |= ARM_SMMU_FEAT_TT_BE;
+		break;
+#else
+	case IDR0_TTENDIAN_LE:
+		smmu->features |= ARM_SMMU_FEAT_TT_LE;
+		break;
+#endif
+	default:
+		dev_err(smmu->dev, "unknown/unsupported TT endianness!\n");
+		return -ENXIO;
+	}
+
+	/* Boolean feature flags */
+	if (IS_ENABLED(CONFIG_PCI_PRI) && reg & IDR0_PRI)
+		smmu->features |= ARM_SMMU_FEAT_PRI;
+
+	if (IS_ENABLED(CONFIG_PCI_ATS) && reg & IDR0_ATS)
+		smmu->features |= ARM_SMMU_FEAT_ATS;
+
+	if (reg & IDR0_SEV)
+		smmu->features |= ARM_SMMU_FEAT_SEV;
+
+	if (reg & IDR0_MSI)
+		smmu->features |= ARM_SMMU_FEAT_MSI;
+
+	if (reg & IDR0_HYP)
+		smmu->features |= ARM_SMMU_FEAT_HYP;
+
+	/*
+	 * The coherency feature as set by FW is used in preference to the ID
+	 * register, but warn on mismatch.
+	 */
+	if (!!(reg & IDR0_COHACC) != coherent)
+		dev_warn(smmu->dev, "IDR0.COHACC overridden by FW configuration (%s)\n",
+			 coherent ? "true" : "false");
+
+	switch (FIELD_GET(IDR0_STALL_MODEL, reg)) {
+	case IDR0_STALL_MODEL_FORCE:
+		smmu->features |= ARM_SMMU_FEAT_STALL_FORCE;
+		/* Fallthrough */
+	case IDR0_STALL_MODEL_STALL:
+		smmu->features |= ARM_SMMU_FEAT_STALLS;
+	}
+
+	if (reg & IDR0_S1P)
+		smmu->features |= ARM_SMMU_FEAT_TRANS_S1;
+
+	if (reg & IDR0_S2P)
+		smmu->features |= ARM_SMMU_FEAT_TRANS_S2;
+
+	if (!(reg & (IDR0_S1P | IDR0_S2P))) {
+		dev_err(smmu->dev, "no translation support!\n");
+		return -ENXIO;
+	}
+
+	/* We only support the AArch64 table format at present */
+	switch (FIELD_GET(IDR0_TTF, reg)) {
+	case IDR0_TTF_AARCH32_64:
+		smmu->ias = 40;
+		/* Fallthrough */
+	case IDR0_TTF_AARCH64:
+		break;
+	default:
+		dev_err(smmu->dev, "AArch64 table format not supported!\n");
+		return -ENXIO;
+	}
+
+	/* ASID/VMID sizes */
+	smmu->asid_bits = reg & IDR0_ASID16 ? 16 : 8;
+	smmu->vmid_bits = reg & IDR0_VMID16 ? 16 : 8;
+
+	/* IDR1 */
+	reg = readl_relaxed(smmu->base + ARM_SMMU_IDR1);
+	if (reg & (IDR1_TABLES_PRESET | IDR1_QUEUES_PRESET | IDR1_REL)) {
+		dev_err(smmu->dev, "embedded implementation not supported\n");
+		return -ENXIO;
+	}
+
+	/* Queue sizes, capped to ensure natural alignment */
+	smmu->cmdq.q.llq.max_n_shift = min_t(u32, CMDQ_MAX_SZ_SHIFT,
+					     FIELD_GET(IDR1_CMDQS, reg));
+	if (smmu->cmdq.q.llq.max_n_shift <= ilog2(CMDQ_BATCH_ENTRIES)) {
+		/*
+		 * We don't support splitting up batches, so one batch of
+		 * commands plus an extra sync needs to fit inside the command
+		 * queue. There's also no way we can handle the weird alignment
+		 * restrictions on the base pointer for a unit-length queue.
+		 */
+		dev_err(smmu->dev, "command queue size <= %d entries not supported\n",
+			CMDQ_BATCH_ENTRIES);
+		return -ENXIO;
+	}
+
+	smmu->evtq.q.llq.max_n_shift = min_t(u32, EVTQ_MAX_SZ_SHIFT,
+					     FIELD_GET(IDR1_EVTQS, reg));
+	smmu->priq.q.llq.max_n_shift = min_t(u32, PRIQ_MAX_SZ_SHIFT,
+					     FIELD_GET(IDR1_PRIQS, reg));
+
+	/* SID/SSID sizes */
+	smmu->ssid_bits = FIELD_GET(IDR1_SSIDSIZE, reg);
+	smmu->sid_bits = FIELD_GET(IDR1_SIDSIZE, reg);
+
+	/*
+	 * If the SMMU supports fewer bits than would fill a single L2 stream
+	 * table, use a linear table instead.
+	 */
+	if (smmu->sid_bits <= STRTAB_SPLIT)
+		smmu->features &= ~ARM_SMMU_FEAT_2_LVL_STRTAB;
+
+	/* IDR3 */
+	reg = readl_relaxed(smmu->base + ARM_SMMU_IDR3);
+	if (FIELD_GET(IDR3_RIL, reg))
+		smmu->features |= ARM_SMMU_FEAT_RANGE_INV;
+
+	/* IDR5 */
+	reg = readl_relaxed(smmu->base + ARM_SMMU_IDR5);
+
+	/* Maximum number of outstanding stalls */
+	smmu->evtq.max_stalls = FIELD_GET(IDR5_STALL_MAX, reg);
+
+	/* Page sizes */
+	if (reg & IDR5_GRAN64K)
+		smmu->pgsize_bitmap |= SZ_64K | SZ_512M;
+	if (reg & IDR5_GRAN16K)
+		smmu->pgsize_bitmap |= SZ_16K | SZ_32M;
+	if (reg & IDR5_GRAN4K)
+		smmu->pgsize_bitmap |= SZ_4K | SZ_2M | SZ_1G;
+
+	/* Input address size */
+	if (FIELD_GET(IDR5_VAX, reg) == IDR5_VAX_52_BIT)
+		smmu->features |= ARM_SMMU_FEAT_VAX;
+
+	/* Output address size */
+	switch (FIELD_GET(IDR5_OAS, reg)) {
+	case IDR5_OAS_32_BIT:
+		smmu->oas = 32;
+		break;
+	case IDR5_OAS_36_BIT:
+		smmu->oas = 36;
+		break;
+	case IDR5_OAS_40_BIT:
+		smmu->oas = 40;
+		break;
+	case IDR5_OAS_42_BIT:
+		smmu->oas = 42;
+		break;
+	case IDR5_OAS_44_BIT:
+		smmu->oas = 44;
+		break;
+	case IDR5_OAS_52_BIT:
+		smmu->oas = 52;
+		smmu->pgsize_bitmap |= 1ULL << 42; /* 4TB */
+		break;
+	default:
+		dev_info(smmu->dev,
+			"unknown output address size. Truncating to 48-bit\n");
+		/* Fallthrough */
+	case IDR5_OAS_48_BIT:
+		smmu->oas = 48;
+	}
+
+	if (arm_smmu_ops.pgsize_bitmap == -1UL)
+		arm_smmu_ops.pgsize_bitmap = smmu->pgsize_bitmap;
+	else
+		arm_smmu_ops.pgsize_bitmap |= smmu->pgsize_bitmap;
+
+	/* Set the DMA mask for our table walker */
+	if (dma_set_mask_and_coherent(smmu->dev, DMA_BIT_MASK(smmu->oas)))
+		dev_warn(smmu->dev,
+			 "failed to set DMA mask for table walker\n");
+
+	smmu->ias = max(smmu->ias, smmu->oas);
+
+	dev_info(smmu->dev, "ias %lu-bit, oas %lu-bit (features 0x%08x)\n",
+		 smmu->ias, smmu->oas, smmu->features);
+	return 0;
+}
+
+#ifdef CONFIG_ACPI
+static void acpi_smmu_get_options(u32 model, struct arm_smmu_device *smmu)
+{
+	switch (model) {
+	case ACPI_IORT_SMMU_V3_CAVIUM_CN99XX:
+		smmu->options |= ARM_SMMU_OPT_PAGE0_REGS_ONLY;
+		break;
+	case ACPI_IORT_SMMU_V3_HISILICON_HI161X:
+		smmu->options |= ARM_SMMU_OPT_SKIP_PREFETCH;
+		break;
+	}
+
+	dev_notice(smmu->dev, "option mask 0x%x\n", smmu->options);
+}
+
+static int arm_smmu_device_acpi_probe(struct platform_device *pdev,
+				      struct arm_smmu_device *smmu)
+{
+	struct acpi_iort_smmu_v3 *iort_smmu;
+	struct device *dev = smmu->dev;
+	struct acpi_iort_node *node;
+
+	node = *(struct acpi_iort_node **)dev_get_platdata(dev);
+
+	/* Retrieve SMMUv3 specific data */
+	iort_smmu = (struct acpi_iort_smmu_v3 *)node->node_data;
+
+	acpi_smmu_get_options(iort_smmu->model, smmu);
+
+	if (iort_smmu->flags & ACPI_IORT_SMMU_V3_COHACC_OVERRIDE)
+		smmu->features |= ARM_SMMU_FEAT_COHERENCY;
+
+	return 0;
+}
+#else
+static inline int arm_smmu_device_acpi_probe(struct platform_device *pdev,
+					     struct arm_smmu_device *smmu)
+{
+	return -ENODEV;
+}
+#endif
+
+static int arm_smmu_device_dt_probe(struct platform_device *pdev,
+				    struct arm_smmu_device *smmu)
+{
+	struct device *dev = &pdev->dev;
+	u32 cells;
+	int ret = -EINVAL;
+
+	if (of_property_read_u32(dev->of_node, "#iommu-cells", &cells))
+		dev_err(dev, "missing #iommu-cells property\n");
+	else if (cells != 1)
+		dev_err(dev, "invalid #iommu-cells value (%d)\n", cells);
+	else
+		ret = 0;
+
+	parse_driver_options(smmu);
+
+	if (of_dma_is_coherent(dev->of_node))
+		smmu->features |= ARM_SMMU_FEAT_COHERENCY;
+
+	return ret;
+}
+
+static unsigned long arm_smmu_resource_size(struct arm_smmu_device *smmu)
+{
+	if (smmu->options & ARM_SMMU_OPT_PAGE0_REGS_ONLY)
+		return SZ_64K;
+	else
+		return SZ_128K;
+}
+
+static int arm_smmu_set_bus_ops(struct iommu_ops *ops)
+{
+	int err;
+
+#ifdef CONFIG_PCI
+	if (pci_bus_type.iommu_ops != ops) {
+		err = bus_set_iommu(&pci_bus_type, ops);
+		if (err)
+			return err;
+	}
+#endif
+#ifdef CONFIG_ARM_AMBA
+	if (amba_bustype.iommu_ops != ops) {
+		err = bus_set_iommu(&amba_bustype, ops);
+		if (err)
+			goto err_reset_pci_ops;
+	}
+#endif
+	if (platform_bus_type.iommu_ops != ops) {
+		err = bus_set_iommu(&platform_bus_type, ops);
+		if (err)
+			goto err_reset_amba_ops;
+	}
+
+	return 0;
+
+err_reset_amba_ops:
+#ifdef CONFIG_ARM_AMBA
+	bus_set_iommu(&amba_bustype, NULL);
+#endif
+err_reset_pci_ops: __maybe_unused;
+#ifdef CONFIG_PCI
+	bus_set_iommu(&pci_bus_type, NULL);
+#endif
+	return err;
+}
+
+static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
+				      resource_size_t size)
+{
+	struct resource res = {
+		.flags = IORESOURCE_MEM,
+		.start = start,
+		.end = start + size - 1,
+	};
+
+	return devm_ioremap_resource(dev, &res);
+}
+
+static int arm_smmu_device_probe(struct platform_device *pdev)
+{
+	int irq, ret;
+	struct resource *res;
+	resource_size_t ioaddr;
+	struct arm_smmu_device *smmu;
+	struct device *dev = &pdev->dev;
+	bool bypass;
+
+	smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
+	if (!smmu) {
+		dev_err(dev, "failed to allocate arm_smmu_device\n");
+		return -ENOMEM;
+	}
+	smmu->dev = dev;
+
+	if (dev->of_node) {
+		ret = arm_smmu_device_dt_probe(pdev, smmu);
+	} else {
+		ret = arm_smmu_device_acpi_probe(pdev, smmu);
+		if (ret == -ENODEV)
+			return ret;
+	}
+
+	/* Set bypass mode according to firmware probing result */
+	bypass = !!ret;
+
+	/* Base address */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (resource_size(res) < arm_smmu_resource_size(smmu)) {
+		dev_err(dev, "MMIO region too small (%pr)\n", res);
+		return -EINVAL;
+	}
+	ioaddr = res->start;
+
+	/*
+	 * Don't map the IMPLEMENTATION DEFINED regions, since they may contain
+	 * the PMCG registers which are reserved by the PMU driver.
+	 */
+	smmu->base = arm_smmu_ioremap(dev, ioaddr, ARM_SMMU_REG_SZ);
+	if (IS_ERR(smmu->base))
+		return PTR_ERR(smmu->base);
+
+	if (arm_smmu_resource_size(smmu) > SZ_64K) {
+		smmu->page1 = arm_smmu_ioremap(dev, ioaddr + SZ_64K,
+					       ARM_SMMU_REG_SZ);
+		if (IS_ERR(smmu->page1))
+			return PTR_ERR(smmu->page1);
+	} else {
+		smmu->page1 = smmu->base;
+	}
+
+	/* Interrupt lines */
+
+	irq = platform_get_irq_byname_optional(pdev, "combined");
+	if (irq > 0)
+		smmu->combined_irq = irq;
+	else {
+		irq = platform_get_irq_byname_optional(pdev, "eventq");
+		if (irq > 0)
+			smmu->evtq.q.irq = irq;
+
+		irq = platform_get_irq_byname_optional(pdev, "priq");
+		if (irq > 0)
+			smmu->priq.q.irq = irq;
+
+		irq = platform_get_irq_byname_optional(pdev, "gerror");
+		if (irq > 0)
+			smmu->gerr_irq = irq;
+	}
+	/* Probe the h/w */
+	ret = arm_smmu_device_hw_probe(smmu);
+	if (ret)
+		return ret;
+
+	/* Initialise in-memory data structures */
+	ret = arm_smmu_init_structures(smmu);
+	if (ret)
+		return ret;
+
+	/* Record our private device structure */
+	platform_set_drvdata(pdev, smmu);
+
+	/* Reset the device */
+	ret = arm_smmu_device_reset(smmu, bypass);
+	if (ret)
+		return ret;
+
+	/* And we're up. Go go go! */
+	ret = iommu_device_sysfs_add(&smmu->iommu, dev, NULL,
+				     "smmu3.%pa", &ioaddr);
+	if (ret)
+		return ret;
+
+	iommu_device_set_ops(&smmu->iommu, &arm_smmu_ops);
+	iommu_device_set_fwnode(&smmu->iommu, dev->fwnode);
+
+	ret = iommu_device_register(&smmu->iommu);
+	if (ret) {
+		dev_err(dev, "Failed to register iommu\n");
+		return ret;
+	}
+
+	return arm_smmu_set_bus_ops(&arm_smmu_ops);
+}
+
+static int arm_smmu_device_remove(struct platform_device *pdev)
+{
+	struct arm_smmu_device *smmu = platform_get_drvdata(pdev);
+
+	arm_smmu_set_bus_ops(NULL);
+	iommu_device_unregister(&smmu->iommu);
+	iommu_device_sysfs_remove(&smmu->iommu);
+	arm_smmu_device_disable(smmu);
+
+	return 0;
+}
+
+static void arm_smmu_device_shutdown(struct platform_device *pdev)
+{
+	arm_smmu_device_remove(pdev);
+}
+
+static const struct of_device_id arm_smmu_of_match[] = {
+	{ .compatible = "arm,smmu-v3", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, arm_smmu_of_match);
+
+static struct platform_driver arm_smmu_driver = {
+	.driver	= {
+		.name			= "arm-smmu-v3",
+		.of_match_table		= arm_smmu_of_match,
+		.suppress_bind_attrs	= true,
+	},
+	.probe	= arm_smmu_device_probe,
+	.remove	= arm_smmu_device_remove,
+	.shutdown = arm_smmu_device_shutdown,
+};
+module_platform_driver(arm_smmu_driver);
+
+MODULE_DESCRIPTION("IOMMU API for ARM architected SMMUv3 implementations");
+MODULE_AUTHOR("Will Deacon <will@kernel.org>");
+MODULE_ALIAS("platform:arm-smmu-v3");
+MODULE_LICENSE("GPL v2");
-- 
2.17.1



^ permalink raw reply related	[flat|nested] 24+ messages in thread

* [PATCH v5 02/10] xen/arm: Revert atomic operation related command-queue insertion patch
  2021-01-20 14:52 [PATCH v5 00/10] xen/arm: Add support for SMMUv3 driver Rahul Singh
  2021-01-20 14:52 ` [PATCH v5 01/10] xen/arm: smmuv3: Import the SMMUv3 driver from Linux Rahul Singh
@ 2021-01-20 14:52 ` Rahul Singh
  2021-01-20 14:52 ` [PATCH v5 03/10] xen/arm: smmuv3: Revert patch related to XArray Rahul Singh
                   ` (7 subsequent siblings)
  9 siblings, 0 replies; 24+ messages in thread
From: Rahul Singh @ 2021-01-20 14:52 UTC (permalink / raw)
  To: xen-devel
  Cc: bertrand.marquis, rahul.singh, Stefano Stabellini, Julien Grall,
	Volodymyr Babchuk

Linux SMMUv3 code implements the commands-queue insertion based on
atomic operations implemented in Linux. Atomic functions used by the
commands-queue insertion are not implemented in XEN therefore revert the
patch that implemented the commands-queue insertion based on atomic
operations.

Reverted the other patches also that are implemented based on the code
that introduced the atomic-operations.

Atomic operations are introduced in the patch "iommu/arm-smmu-v3: Reduce
contention during command-queue insertion" that fixed the bottleneck of
the SMMU command queue insertion operation. A new algorithm for
inserting commands into the queue is introduced in this patch, which is
lock-free on the fast-path.

Consequence of reverting the patch is that the command queue insertion
will be slow for large systems as spinlock will be used to serializes
accesses from all CPUs to the single queue supported by the hardware.

Once the proper atomic operations will be available in XEN the driver
can be updated.

Following commits are reverted in this patch:
1. "iommu/arm-smmu-v3: Add SMMUv3.2 range invalidation support"
    commit 6a481a95d4c198a2dd0a61f8877b92a375757db8.
2. "iommu/arm-smmu-v3: Batch ATC invalidation commands"
    commit 9e773aee8c3e1b3ba019c5c7f8435aaa836c6130.
3. "iommu/arm-smmu-v3: Batch context descriptor invalidation"
    commit edd0351e7bc49555d8b5ad8438a65a7ca262c9f0.
4. "iommu/arm-smmu-v3: Add command queue batching helpers
    commit 4ce8da453640147101bda418640394637c1a7cfc.
5. "iommu/arm-smmu-v3: Fix ATC invalidation ordering wrt main TLBs"
    commit 353e3cf8590cf182a9f42e67993de3aca91e8090.
6. "iommu/arm-smmu-v3: Defer TLB invalidation until ->iotlb_sync()"
    commit 2af2e72b18b499fa36d3f7379fd010ff25d2a984.
7. "iommu/arm-smmu-v3: Reduce contention during command-queue insertion"
    commit 587e6c10a7ce89a5924fdbeff2ec524fbd6a124b.

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
Changes since v2:
- Added consequences of reverting this patch in commit message.
- List all the commits that are reverted in this patch in commit
  message.
Changes since v3: No changes
Changes since v4: No changes
---
---
 xen/drivers/passthrough/arm/smmu-v3.c | 878 ++++++--------------------
 1 file changed, 186 insertions(+), 692 deletions(-)

diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
index f578677a5c..8b7747ed38 100644
--- a/xen/drivers/passthrough/arm/smmu-v3.c
+++ b/xen/drivers/passthrough/arm/smmu-v3.c
@@ -69,9 +69,6 @@
 #define IDR1_SSIDSIZE			GENMASK(10, 6)
 #define IDR1_SIDSIZE			GENMASK(5, 0)
 
-#define ARM_SMMU_IDR3			0xc
-#define IDR3_RIL			(1 << 10)
-
 #define ARM_SMMU_IDR5			0x14
 #define IDR5_STALL_MAX			GENMASK(31, 16)
 #define IDR5_GRAN64K			(1 << 6)
@@ -187,7 +184,7 @@
 
 #define Q_IDX(llq, p)			((p) & ((1 << (llq)->max_n_shift) - 1))
 #define Q_WRP(llq, p)			((p) & (1 << (llq)->max_n_shift))
-#define Q_OVERFLOW_FLAG			(1U << 31)
+#define Q_OVERFLOW_FLAG			(1 << 31)
 #define Q_OVF(p)			((p) & Q_OVERFLOW_FLAG)
 #define Q_ENT(q, p)			((q)->base +			\
 					 Q_IDX(&((q)->llq), p) *	\
@@ -330,15 +327,6 @@
 #define CMDQ_ERR_CERROR_ABT_IDX		2
 #define CMDQ_ERR_CERROR_ATC_INV_IDX	3
 
-#define CMDQ_PROD_OWNED_FLAG		Q_OVERFLOW_FLAG
-
-/*
- * This is used to size the command queue and therefore must be at least
- * BITS_PER_LONG so that the valid_map works correctly (it relies on the
- * total number of queue entries being a multiple of BITS_PER_LONG).
- */
-#define CMDQ_BATCH_ENTRIES		BITS_PER_LONG
-
 #define CMDQ_0_OP			GENMASK_ULL(7, 0)
 #define CMDQ_0_SSV			(1UL << 11)
 
@@ -351,14 +339,9 @@
 #define CMDQ_CFGI_1_LEAF		(1UL << 0)
 #define CMDQ_CFGI_1_RANGE		GENMASK_ULL(4, 0)
 
-#define CMDQ_TLBI_0_NUM			GENMASK_ULL(16, 12)
-#define CMDQ_TLBI_RANGE_NUM_MAX		31
-#define CMDQ_TLBI_0_SCALE		GENMASK_ULL(24, 20)
 #define CMDQ_TLBI_0_VMID		GENMASK_ULL(47, 32)
 #define CMDQ_TLBI_0_ASID		GENMASK_ULL(63, 48)
 #define CMDQ_TLBI_1_LEAF		(1UL << 0)
-#define CMDQ_TLBI_1_TTL			GENMASK_ULL(9, 8)
-#define CMDQ_TLBI_1_TG			GENMASK_ULL(11, 10)
 #define CMDQ_TLBI_1_VA_MASK		GENMASK_ULL(63, 12)
 #define CMDQ_TLBI_1_IPA_MASK		GENMASK_ULL(51, 12)
 
@@ -407,8 +390,9 @@
 #define PRIQ_1_ADDR_MASK		GENMASK_ULL(63, 12)
 
 /* High-level queue structures */
-#define ARM_SMMU_POLL_TIMEOUT_US	1000000 /* 1s! */
-#define ARM_SMMU_POLL_SPIN_COUNT	10
+#define ARM_SMMU_POLL_TIMEOUT_US	100
+#define ARM_SMMU_CMDQ_SYNC_TIMEOUT_US	1000000 /* 1s! */
+#define ARM_SMMU_CMDQ_SYNC_SPIN_COUNT	10
 
 #define MSI_IOVA_BASE			0x8000000
 #define MSI_IOVA_LENGTH			0x100000
@@ -483,13 +467,9 @@ struct arm_smmu_cmdq_ent {
 		#define CMDQ_OP_TLBI_S2_IPA	0x2a
 		#define CMDQ_OP_TLBI_NSNH_ALL	0x30
 		struct {
-			u8			num;
-			u8			scale;
 			u16			asid;
 			u16			vmid;
 			bool			leaf;
-			u8			ttl;
-			u8			tg;
 			u64			addr;
 		} tlbi;
 
@@ -513,24 +493,15 @@ struct arm_smmu_cmdq_ent {
 
 		#define CMDQ_OP_CMD_SYNC	0x46
 		struct {
+			u32			msidata;
 			u64			msiaddr;
 		} sync;
 	};
 };
 
 struct arm_smmu_ll_queue {
-	union {
-		u64			val;
-		struct {
-			u32		prod;
-			u32		cons;
-		};
-		struct {
-			atomic_t	prod;
-			atomic_t	cons;
-		} atomic;
-		u8			__pad[SMP_CACHE_BYTES];
-	} ____cacheline_aligned_in_smp;
+	u32				prod;
+	u32				cons;
 	u32				max_n_shift;
 };
 
@@ -548,23 +519,9 @@ struct arm_smmu_queue {
 	u32 __iomem			*cons_reg;
 };
 
-struct arm_smmu_queue_poll {
-	ktime_t				timeout;
-	unsigned int			delay;
-	unsigned int			spin_cnt;
-	bool				wfe;
-};
-
 struct arm_smmu_cmdq {
 	struct arm_smmu_queue		q;
-	atomic_long_t			*valid_map;
-	atomic_t			owner_prod;
-	atomic_t			lock;
-};
-
-struct arm_smmu_cmdq_batch {
-	u64				cmds[CMDQ_BATCH_ENTRIES * CMDQ_ENT_DWORDS];
-	int				num;
+	spinlock_t			lock;
 };
 
 struct arm_smmu_evtq {
@@ -647,7 +604,6 @@ struct arm_smmu_device {
 #define ARM_SMMU_FEAT_HYP		(1 << 12)
 #define ARM_SMMU_FEAT_STALL_FORCE	(1 << 13)
 #define ARM_SMMU_FEAT_VAX		(1 << 14)
-#define ARM_SMMU_FEAT_RANGE_INV		(1 << 15)
 	u32				features;
 
 #define ARM_SMMU_OPT_SKIP_PREFETCH	(1 << 0)
@@ -660,6 +616,8 @@ struct arm_smmu_device {
 
 	int				gerr_irq;
 	int				combined_irq;
+	u32				sync_nr;
+	u8				prev_cmd_opcode;
 
 	unsigned long			ias; /* IPA */
 	unsigned long			oas; /* PA */
@@ -677,6 +635,12 @@ struct arm_smmu_device {
 
 	struct arm_smmu_strtab_cfg	strtab_cfg;
 
+	/* Hi16xx adds an extra 32 bits of goodness to its MSI payload */
+	union {
+		u32			sync_count;
+		u64			padding;
+	};
+
 	/* IOMMU core code handle */
 	struct iommu_device		iommu;
 };
@@ -763,21 +727,6 @@ static void parse_driver_options(struct arm_smmu_device *smmu)
 }
 
 /* Low-level queue manipulation functions */
-static bool queue_has_space(struct arm_smmu_ll_queue *q, u32 n)
-{
-	u32 space, prod, cons;
-
-	prod = Q_IDX(q, q->prod);
-	cons = Q_IDX(q, q->cons);
-
-	if (Q_WRP(q, q->prod) == Q_WRP(q, q->cons))
-		space = (1 << q->max_n_shift) - (prod - cons);
-	else
-		space = cons - prod;
-
-	return space >= n;
-}
-
 static bool queue_full(struct arm_smmu_ll_queue *q)
 {
 	return Q_IDX(q, q->prod) == Q_IDX(q, q->cons) &&
@@ -790,12 +739,9 @@ static bool queue_empty(struct arm_smmu_ll_queue *q)
 	       Q_WRP(q, q->prod) == Q_WRP(q, q->cons);
 }
 
-static bool queue_consumed(struct arm_smmu_ll_queue *q, u32 prod)
+static void queue_sync_cons_in(struct arm_smmu_queue *q)
 {
-	return ((Q_WRP(q, q->cons) == Q_WRP(q, prod)) &&
-		(Q_IDX(q, q->cons) > Q_IDX(q, prod))) ||
-	       ((Q_WRP(q, q->cons) != Q_WRP(q, prod)) &&
-		(Q_IDX(q, q->cons) <= Q_IDX(q, prod)));
+	q->llq.cons = readl_relaxed(q->cons_reg);
 }
 
 static void queue_sync_cons_out(struct arm_smmu_queue *q)
@@ -826,34 +772,46 @@ static int queue_sync_prod_in(struct arm_smmu_queue *q)
 	return ret;
 }
 
-static u32 queue_inc_prod_n(struct arm_smmu_ll_queue *q, int n)
+static void queue_sync_prod_out(struct arm_smmu_queue *q)
 {
-	u32 prod = (Q_WRP(q, q->prod) | Q_IDX(q, q->prod)) + n;
-	return Q_OVF(q->prod) | Q_WRP(q, prod) | Q_IDX(q, prod);
+	writel(q->llq.prod, q->prod_reg);
 }
 
-static void queue_poll_init(struct arm_smmu_device *smmu,
-			    struct arm_smmu_queue_poll *qp)
+static void queue_inc_prod(struct arm_smmu_ll_queue *q)
 {
-	qp->delay = 1;
-	qp->spin_cnt = 0;
-	qp->wfe = !!(smmu->features & ARM_SMMU_FEAT_SEV);
-	qp->timeout = ktime_add_us(ktime_get(), ARM_SMMU_POLL_TIMEOUT_US);
+	u32 prod = (Q_WRP(q, q->prod) | Q_IDX(q, q->prod)) + 1;
+	q->prod = Q_OVF(q->prod) | Q_WRP(q, prod) | Q_IDX(q, prod);
 }
 
-static int queue_poll(struct arm_smmu_queue_poll *qp)
+/*
+ * Wait for the SMMU to consume items. If sync is true, wait until the queue
+ * is empty. Otherwise, wait until there is at least one free slot.
+ */
+static int queue_poll_cons(struct arm_smmu_queue *q, bool sync, bool wfe)
 {
-	if (ktime_compare(ktime_get(), qp->timeout) > 0)
-		return -ETIMEDOUT;
+	ktime_t timeout;
+	unsigned int delay = 1, spin_cnt = 0;
 
-	if (qp->wfe) {
-		wfe();
-	} else if (++qp->spin_cnt < ARM_SMMU_POLL_SPIN_COUNT) {
-		cpu_relax();
-	} else {
-		udelay(qp->delay);
-		qp->delay *= 2;
-		qp->spin_cnt = 0;
+	/* Wait longer if it's a CMD_SYNC */
+	timeout = ktime_add_us(ktime_get(), sync ?
+					    ARM_SMMU_CMDQ_SYNC_TIMEOUT_US :
+					    ARM_SMMU_POLL_TIMEOUT_US);
+
+	while (queue_sync_cons_in(q),
+	      (sync ? !queue_empty(&q->llq) : queue_full(&q->llq))) {
+		if (ktime_compare(ktime_get(), timeout) > 0)
+			return -ETIMEDOUT;
+
+		if (wfe) {
+			wfe();
+		} else if (++spin_cnt < ARM_SMMU_CMDQ_SYNC_SPIN_COUNT) {
+			cpu_relax();
+			continue;
+		} else {
+			udelay(delay);
+			delay *= 2;
+			spin_cnt = 0;
+		}
 	}
 
 	return 0;
@@ -867,6 +825,17 @@ static void queue_write(__le64 *dst, u64 *src, size_t n_dwords)
 		*dst++ = cpu_to_le64(*src++);
 }
 
+static int queue_insert_raw(struct arm_smmu_queue *q, u64 *ent)
+{
+	if (queue_full(&q->llq))
+		return -ENOSPC;
+
+	queue_write(Q_ENT(q, q->llq.prod), ent, q->ent_dwords);
+	queue_inc_prod(&q->llq);
+	queue_sync_prod_out(q);
+	return 0;
+}
+
 static void queue_read(__le64 *dst, u64 *src, size_t n_dwords)
 {
 	int i;
@@ -916,22 +885,14 @@ static int arm_smmu_cmdq_build_cmd(u64 *cmd, struct arm_smmu_cmdq_ent *ent)
 		cmd[1] |= FIELD_PREP(CMDQ_CFGI_1_RANGE, 31);
 		break;
 	case CMDQ_OP_TLBI_NH_VA:
-		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_NUM, ent->tlbi.num);
-		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_SCALE, ent->tlbi.scale);
 		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_VMID, ent->tlbi.vmid);
 		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_ASID, ent->tlbi.asid);
 		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_LEAF, ent->tlbi.leaf);
-		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_TTL, ent->tlbi.ttl);
-		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_TG, ent->tlbi.tg);
 		cmd[1] |= ent->tlbi.addr & CMDQ_TLBI_1_VA_MASK;
 		break;
 	case CMDQ_OP_TLBI_S2_IPA:
-		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_NUM, ent->tlbi.num);
-		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_SCALE, ent->tlbi.scale);
 		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_VMID, ent->tlbi.vmid);
 		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_LEAF, ent->tlbi.leaf);
-		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_TTL, ent->tlbi.ttl);
-		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_TG, ent->tlbi.tg);
 		cmd[1] |= ent->tlbi.addr & CMDQ_TLBI_1_IPA_MASK;
 		break;
 	case CMDQ_OP_TLBI_NH_ASID:
@@ -964,14 +925,20 @@ static int arm_smmu_cmdq_build_cmd(u64 *cmd, struct arm_smmu_cmdq_ent *ent)
 		cmd[1] |= FIELD_PREP(CMDQ_PRI_1_RESP, ent->pri.resp);
 		break;
 	case CMDQ_OP_CMD_SYNC:
-		if (ent->sync.msiaddr) {
+		if (ent->sync.msiaddr)
 			cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_CS, CMDQ_SYNC_0_CS_IRQ);
-			cmd[1] |= ent->sync.msiaddr & CMDQ_SYNC_1_MSIADDR_MASK;
-		} else {
+		else
 			cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_CS, CMDQ_SYNC_0_CS_SEV);
-		}
 		cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_MSH, ARM_SMMU_SH_ISH);
 		cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_MSIATTR, ARM_SMMU_MEMATTR_OIWB);
+		/*
+		 * Commands are written little-endian, but we want the SMMU to
+		 * receive MSIData, and thus write it back to memory, in CPU
+		 * byte order, so big-endian needs an extra byteswap here.
+		 */
+		cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_MSIDATA,
+				     cpu_to_le32(ent->sync.msidata));
+		cmd[1] |= ent->sync.msiaddr & CMDQ_SYNC_1_MSIADDR_MASK;
 		break;
 	default:
 		return -ENOENT;
@@ -980,27 +947,6 @@ static int arm_smmu_cmdq_build_cmd(u64 *cmd, struct arm_smmu_cmdq_ent *ent)
 	return 0;
 }
 
-static void arm_smmu_cmdq_build_sync_cmd(u64 *cmd, struct arm_smmu_device *smmu,
-					 u32 prod)
-{
-	struct arm_smmu_queue *q = &smmu->cmdq.q;
-	struct arm_smmu_cmdq_ent ent = {
-		.opcode = CMDQ_OP_CMD_SYNC,
-	};
-
-	/*
-	 * Beware that Hi16xx adds an extra 32 bits of goodness to its MSI
-	 * payload, so the write will zero the entire command on that platform.
-	 */
-	if (smmu->features & ARM_SMMU_FEAT_MSI &&
-	    smmu->features & ARM_SMMU_FEAT_COHERENCY) {
-		ent.sync.msiaddr = q->base_dma + Q_IDX(&q->llq, prod) *
-				   q->ent_dwords * 8;
-	}
-
-	arm_smmu_cmdq_build_cmd(cmd, &ent);
-}
-
 static void arm_smmu_cmdq_skip_err(struct arm_smmu_device *smmu)
 {
 	static const char *cerror_str[] = {
@@ -1059,474 +1005,109 @@ static void arm_smmu_cmdq_skip_err(struct arm_smmu_device *smmu)
 	queue_write(Q_ENT(q, cons), cmd, q->ent_dwords);
 }
 
-/*
- * Command queue locking.
- * This is a form of bastardised rwlock with the following major changes:
- *
- * - The only LOCK routines are exclusive_trylock() and shared_lock().
- *   Neither have barrier semantics, and instead provide only a control
- *   dependency.
- *
- * - The UNLOCK routines are supplemented with shared_tryunlock(), which
- *   fails if the caller appears to be the last lock holder (yes, this is
- *   racy). All successful UNLOCK routines have RELEASE semantics.
- */
-static void arm_smmu_cmdq_shared_lock(struct arm_smmu_cmdq *cmdq)
-{
-	int val;
-
-	/*
-	 * We can try to avoid the cmpxchg() loop by simply incrementing the
-	 * lock counter. When held in exclusive state, the lock counter is set
-	 * to INT_MIN so these increments won't hurt as the value will remain
-	 * negative.
-	 */
-	if (atomic_fetch_inc_relaxed(&cmdq->lock) >= 0)
-		return;
-
-	do {
-		val = atomic_cond_read_relaxed(&cmdq->lock, VAL >= 0);
-	} while (atomic_cmpxchg_relaxed(&cmdq->lock, val, val + 1) != val);
-}
-
-static void arm_smmu_cmdq_shared_unlock(struct arm_smmu_cmdq *cmdq)
-{
-	(void)atomic_dec_return_release(&cmdq->lock);
-}
-
-static bool arm_smmu_cmdq_shared_tryunlock(struct arm_smmu_cmdq *cmdq)
+static void arm_smmu_cmdq_insert_cmd(struct arm_smmu_device *smmu, u64 *cmd)
 {
-	if (atomic_read(&cmdq->lock) == 1)
-		return false;
-
-	arm_smmu_cmdq_shared_unlock(cmdq);
-	return true;
-}
-
-#define arm_smmu_cmdq_exclusive_trylock_irqsave(cmdq, flags)		\
-({									\
-	bool __ret;							\
-	local_irq_save(flags);						\
-	__ret = !atomic_cmpxchg_relaxed(&cmdq->lock, 0, INT_MIN);	\
-	if (!__ret)							\
-		local_irq_restore(flags);				\
-	__ret;								\
-})
-
-#define arm_smmu_cmdq_exclusive_unlock_irqrestore(cmdq, flags)		\
-({									\
-	atomic_set_release(&cmdq->lock, 0);				\
-	local_irq_restore(flags);					\
-})
-
-
-/*
- * Command queue insertion.
- * This is made fiddly by our attempts to achieve some sort of scalability
- * since there is one queue shared amongst all of the CPUs in the system.  If
- * you like mixed-size concurrency, dependency ordering and relaxed atomics,
- * then you'll *love* this monstrosity.
- *
- * The basic idea is to split the queue up into ranges of commands that are
- * owned by a given CPU; the owner may not have written all of the commands
- * itself, but is responsible for advancing the hardware prod pointer when
- * the time comes. The algorithm is roughly:
- *
- * 	1. Allocate some space in the queue. At this point we also discover
- *	   whether the head of the queue is currently owned by another CPU,
- *	   or whether we are the owner.
- *
- *	2. Write our commands into our allocated slots in the queue.
- *
- *	3. Mark our slots as valid in arm_smmu_cmdq.valid_map.
- *
- *	4. If we are an owner:
- *		a. Wait for the previous owner to finish.
- *		b. Mark the queue head as unowned, which tells us the range
- *		   that we are responsible for publishing.
- *		c. Wait for all commands in our owned range to become valid.
- *		d. Advance the hardware prod pointer.
- *		e. Tell the next owner we've finished.
- *
- *	5. If we are inserting a CMD_SYNC (we may or may not have been an
- *	   owner), then we need to stick around until it has completed:
- *		a. If we have MSIs, the SMMU can write back into the CMD_SYNC
- *		   to clear the first 4 bytes.
- *		b. Otherwise, we spin waiting for the hardware cons pointer to
- *		   advance past our command.
- *
- * The devil is in the details, particularly the use of locking for handling
- * SYNC completion and freeing up space in the queue before we think that it is
- * full.
- */
-static void __arm_smmu_cmdq_poll_set_valid_map(struct arm_smmu_cmdq *cmdq,
-					       u32 sprod, u32 eprod, bool set)
-{
-	u32 swidx, sbidx, ewidx, ebidx;
-	struct arm_smmu_ll_queue llq = {
-		.max_n_shift	= cmdq->q.llq.max_n_shift,
-		.prod		= sprod,
-	};
-
-	ewidx = BIT_WORD(Q_IDX(&llq, eprod));
-	ebidx = Q_IDX(&llq, eprod) % BITS_PER_LONG;
-
-	while (llq.prod != eprod) {
-		unsigned long mask;
-		atomic_long_t *ptr;
-		u32 limit = BITS_PER_LONG;
-
-		swidx = BIT_WORD(Q_IDX(&llq, llq.prod));
-		sbidx = Q_IDX(&llq, llq.prod) % BITS_PER_LONG;
-
-		ptr = &cmdq->valid_map[swidx];
-
-		if ((swidx == ewidx) && (sbidx < ebidx))
-			limit = ebidx;
-
-		mask = GENMASK(limit - 1, sbidx);
-
-		/*
-		 * The valid bit is the inverse of the wrap bit. This means
-		 * that a zero-initialised queue is invalid and, after marking
-		 * all entries as valid, they become invalid again when we
-		 * wrap.
-		 */
-		if (set) {
-			atomic_long_xor(mask, ptr);
-		} else { /* Poll */
-			unsigned long valid;
+	struct arm_smmu_queue *q = &smmu->cmdq.q;
+	bool wfe = !!(smmu->features & ARM_SMMU_FEAT_SEV);
 
-			valid = (ULONG_MAX + !!Q_WRP(&llq, llq.prod)) & mask;
-			atomic_long_cond_read_relaxed(ptr, (VAL & mask) == valid);
-		}
+	smmu->prev_cmd_opcode = FIELD_GET(CMDQ_0_OP, cmd[0]);
 
-		llq.prod = queue_inc_prod_n(&llq, limit - sbidx);
+	while (queue_insert_raw(q, cmd) == -ENOSPC) {
+		if (queue_poll_cons(q, false, wfe))
+			dev_err_ratelimited(smmu->dev, "CMDQ timeout\n");
 	}
 }
 
-/* Mark all entries in the range [sprod, eprod) as valid */
-static void arm_smmu_cmdq_set_valid_map(struct arm_smmu_cmdq *cmdq,
-					u32 sprod, u32 eprod)
-{
-	__arm_smmu_cmdq_poll_set_valid_map(cmdq, sprod, eprod, true);
-}
-
-/* Wait for all entries in the range [sprod, eprod) to become valid */
-static void arm_smmu_cmdq_poll_valid_map(struct arm_smmu_cmdq *cmdq,
-					 u32 sprod, u32 eprod)
-{
-	__arm_smmu_cmdq_poll_set_valid_map(cmdq, sprod, eprod, false);
-}
-
-/* Wait for the command queue to become non-full */
-static int arm_smmu_cmdq_poll_until_not_full(struct arm_smmu_device *smmu,
-					     struct arm_smmu_ll_queue *llq)
+static void arm_smmu_cmdq_issue_cmd(struct arm_smmu_device *smmu,
+				    struct arm_smmu_cmdq_ent *ent)
 {
+	u64 cmd[CMDQ_ENT_DWORDS];
 	unsigned long flags;
-	struct arm_smmu_queue_poll qp;
-	struct arm_smmu_cmdq *cmdq = &smmu->cmdq;
-	int ret = 0;
 
-	/*
-	 * Try to update our copy of cons by grabbing exclusive cmdq access. If
-	 * that fails, spin until somebody else updates it for us.
-	 */
-	if (arm_smmu_cmdq_exclusive_trylock_irqsave(cmdq, flags)) {
-		WRITE_ONCE(cmdq->q.llq.cons, readl_relaxed(cmdq->q.cons_reg));
-		arm_smmu_cmdq_exclusive_unlock_irqrestore(cmdq, flags);
-		llq->val = READ_ONCE(cmdq->q.llq.val);
-		return 0;
+	if (arm_smmu_cmdq_build_cmd(cmd, ent)) {
+		dev_warn(smmu->dev, "ignoring unknown CMDQ opcode 0x%x\n",
+			 ent->opcode);
+		return;
 	}
 
-	queue_poll_init(smmu, &qp);
-	do {
-		llq->val = READ_ONCE(smmu->cmdq.q.llq.val);
-		if (!queue_full(llq))
-			break;
-
-		ret = queue_poll(&qp);
-	} while (!ret);
-
-	return ret;
+	spin_lock_irqsave(&smmu->cmdq.lock, flags);
+	arm_smmu_cmdq_insert_cmd(smmu, cmd);
+	spin_unlock_irqrestore(&smmu->cmdq.lock, flags);
 }
 
 /*
- * Wait until the SMMU signals a CMD_SYNC completion MSI.
- * Must be called with the cmdq lock held in some capacity.
+ * The difference between val and sync_idx is bounded by the maximum size of
+ * a queue at 2^20 entries, so 32 bits is plenty for wrap-safe arithmetic.
  */
-static int __arm_smmu_cmdq_poll_until_msi(struct arm_smmu_device *smmu,
-					  struct arm_smmu_ll_queue *llq)
-{
-	int ret = 0;
-	struct arm_smmu_queue_poll qp;
-	struct arm_smmu_cmdq *cmdq = &smmu->cmdq;
-	u32 *cmd = (u32 *)(Q_ENT(&cmdq->q, llq->prod));
-
-	queue_poll_init(smmu, &qp);
-
-	/*
-	 * The MSI won't generate an event, since it's being written back
-	 * into the command queue.
-	 */
-	qp.wfe = false;
-	smp_cond_load_relaxed(cmd, !VAL || (ret = queue_poll(&qp)));
-	llq->cons = ret ? llq->prod : queue_inc_prod_n(llq, 1);
-	return ret;
-}
-
-/*
- * Wait until the SMMU cons index passes llq->prod.
- * Must be called with the cmdq lock held in some capacity.
- */
-static int __arm_smmu_cmdq_poll_until_consumed(struct arm_smmu_device *smmu,
-					       struct arm_smmu_ll_queue *llq)
-{
-	struct arm_smmu_queue_poll qp;
-	struct arm_smmu_cmdq *cmdq = &smmu->cmdq;
-	u32 prod = llq->prod;
-	int ret = 0;
-
-	queue_poll_init(smmu, &qp);
-	llq->val = READ_ONCE(smmu->cmdq.q.llq.val);
-	do {
-		if (queue_consumed(llq, prod))
-			break;
-
-		ret = queue_poll(&qp);
-
-		/*
-		 * This needs to be a readl() so that our subsequent call
-		 * to arm_smmu_cmdq_shared_tryunlock() can fail accurately.
-		 *
-		 * Specifically, we need to ensure that we observe all
-		 * shared_lock()s by other CMD_SYNCs that share our owner,
-		 * so that a failing call to tryunlock() means that we're
-		 * the last one out and therefore we can safely advance
-		 * cmdq->q.llq.cons. Roughly speaking:
-		 *
-		 * CPU 0		CPU1			CPU2 (us)
-		 *
-		 * if (sync)
-		 * 	shared_lock();
-		 *
-		 * dma_wmb();
-		 * set_valid_map();
-		 *
-		 * 			if (owner) {
-		 *				poll_valid_map();
-		 *				<control dependency>
-		 *				writel(prod_reg);
-		 *
-		 *						readl(cons_reg);
-		 *						tryunlock();
-		 *
-		 * Requires us to see CPU 0's shared_lock() acquisition.
-		 */
-		llq->cons = readl(cmdq->q.cons_reg);
-	} while (!ret);
-
-	return ret;
-}
-
-static int arm_smmu_cmdq_poll_until_sync(struct arm_smmu_device *smmu,
-					 struct arm_smmu_ll_queue *llq)
+static int __arm_smmu_sync_poll_msi(struct arm_smmu_device *smmu, u32 sync_idx)
 {
-	if (smmu->features & ARM_SMMU_FEAT_MSI &&
-	    smmu->features & ARM_SMMU_FEAT_COHERENCY)
-		return __arm_smmu_cmdq_poll_until_msi(smmu, llq);
-
-	return __arm_smmu_cmdq_poll_until_consumed(smmu, llq);
-}
-
-static void arm_smmu_cmdq_write_entries(struct arm_smmu_cmdq *cmdq, u64 *cmds,
-					u32 prod, int n)
-{
-	int i;
-	struct arm_smmu_ll_queue llq = {
-		.max_n_shift	= cmdq->q.llq.max_n_shift,
-		.prod		= prod,
-	};
+	ktime_t timeout;
+	u32 val;
 
-	for (i = 0; i < n; ++i) {
-		u64 *cmd = &cmds[i * CMDQ_ENT_DWORDS];
+	timeout = ktime_add_us(ktime_get(), ARM_SMMU_CMDQ_SYNC_TIMEOUT_US);
+	val = smp_cond_load_acquire(&smmu->sync_count,
+				    (int)(VAL - sync_idx) >= 0 ||
+				    !ktime_before(ktime_get(), timeout));
 
-		prod = queue_inc_prod_n(&llq, i);
-		queue_write(Q_ENT(&cmdq->q, prod), cmd, CMDQ_ENT_DWORDS);
-	}
+	return (int)(val - sync_idx) < 0 ? -ETIMEDOUT : 0;
 }
 
-/*
- * This is the actual insertion function, and provides the following
- * ordering guarantees to callers:
- *
- * - There is a dma_wmb() before publishing any commands to the queue.
- *   This can be relied upon to order prior writes to data structures
- *   in memory (such as a CD or an STE) before the command.
- *
- * - On completion of a CMD_SYNC, there is a control dependency.
- *   This can be relied upon to order subsequent writes to memory (e.g.
- *   freeing an IOVA) after completion of the CMD_SYNC.
- *
- * - Command insertion is totally ordered, so if two CPUs each race to
- *   insert their own list of commands then all of the commands from one
- *   CPU will appear before any of the commands from the other CPU.
- */
-static int arm_smmu_cmdq_issue_cmdlist(struct arm_smmu_device *smmu,
-				       u64 *cmds, int n, bool sync)
+static int __arm_smmu_cmdq_issue_sync_msi(struct arm_smmu_device *smmu)
 {
-	u64 cmd_sync[CMDQ_ENT_DWORDS];
-	u32 prod;
+	u64 cmd[CMDQ_ENT_DWORDS];
 	unsigned long flags;
-	bool owner;
-	struct arm_smmu_cmdq *cmdq = &smmu->cmdq;
-	struct arm_smmu_ll_queue llq = {
-		.max_n_shift = cmdq->q.llq.max_n_shift,
-	}, head = llq;
-	int ret = 0;
-
-	/* 1. Allocate some space in the queue */
-	local_irq_save(flags);
-	llq.val = READ_ONCE(cmdq->q.llq.val);
-	do {
-		u64 old;
-
-		while (!queue_has_space(&llq, n + sync)) {
-			local_irq_restore(flags);
-			if (arm_smmu_cmdq_poll_until_not_full(smmu, &llq))
-				dev_err_ratelimited(smmu->dev, "CMDQ timeout\n");
-			local_irq_save(flags);
-		}
-
-		head.cons = llq.cons;
-		head.prod = queue_inc_prod_n(&llq, n + sync) |
-					     CMDQ_PROD_OWNED_FLAG;
-
-		old = cmpxchg_relaxed(&cmdq->q.llq.val, llq.val, head.val);
-		if (old == llq.val)
-			break;
-
-		llq.val = old;
-	} while (1);
-	owner = !(llq.prod & CMDQ_PROD_OWNED_FLAG);
-	head.prod &= ~CMDQ_PROD_OWNED_FLAG;
-	llq.prod &= ~CMDQ_PROD_OWNED_FLAG;
-
-	/*
-	 * 2. Write our commands into the queue
-	 * Dependency ordering from the cmpxchg() loop above.
-	 */
-	arm_smmu_cmdq_write_entries(cmdq, cmds, llq.prod, n);
-	if (sync) {
-		prod = queue_inc_prod_n(&llq, n);
-		arm_smmu_cmdq_build_sync_cmd(cmd_sync, smmu, prod);
-		queue_write(Q_ENT(&cmdq->q, prod), cmd_sync, CMDQ_ENT_DWORDS);
-
-		/*
-		 * In order to determine completion of our CMD_SYNC, we must
-		 * ensure that the queue can't wrap twice without us noticing.
-		 * We achieve that by taking the cmdq lock as shared before
-		 * marking our slot as valid.
-		 */
-		arm_smmu_cmdq_shared_lock(cmdq);
-	}
-
-	/* 3. Mark our slots as valid, ensuring commands are visible first */
-	dma_wmb();
-	arm_smmu_cmdq_set_valid_map(cmdq, llq.prod, head.prod);
-
-	/* 4. If we are the owner, take control of the SMMU hardware */
-	if (owner) {
-		/* a. Wait for previous owner to finish */
-		atomic_cond_read_relaxed(&cmdq->owner_prod, VAL == llq.prod);
-
-		/* b. Stop gathering work by clearing the owned flag */
-		prod = atomic_fetch_andnot_relaxed(CMDQ_PROD_OWNED_FLAG,
-						   &cmdq->q.llq.atomic.prod);
-		prod &= ~CMDQ_PROD_OWNED_FLAG;
-
-		/*
-		 * c. Wait for any gathered work to be written to the queue.
-		 * Note that we read our own entries so that we have the control
-		 * dependency required by (d).
-		 */
-		arm_smmu_cmdq_poll_valid_map(cmdq, llq.prod, prod);
+	struct arm_smmu_cmdq_ent ent = {
+		.opcode = CMDQ_OP_CMD_SYNC,
+		.sync	= {
+			.msiaddr = virt_to_phys(&smmu->sync_count),
+		},
+	};
 
-		/*
-		 * d. Advance the hardware prod pointer
-		 * Control dependency ordering from the entries becoming valid.
-		 */
-		writel_relaxed(prod, cmdq->q.prod_reg);
+	spin_lock_irqsave(&smmu->cmdq.lock, flags);
 
-		/*
-		 * e. Tell the next owner we're done
-		 * Make sure we've updated the hardware first, so that we don't
-		 * race to update prod and potentially move it backwards.
-		 */
-		atomic_set_release(&cmdq->owner_prod, prod);
+	/* Piggy-back on the previous command if it's a SYNC */
+	if (smmu->prev_cmd_opcode == CMDQ_OP_CMD_SYNC) {
+		ent.sync.msidata = smmu->sync_nr;
+	} else {
+		ent.sync.msidata = ++smmu->sync_nr;
+		arm_smmu_cmdq_build_cmd(cmd, &ent);
+		arm_smmu_cmdq_insert_cmd(smmu, cmd);
 	}
 
-	/* 5. If we are inserting a CMD_SYNC, we must wait for it to complete */
-	if (sync) {
-		llq.prod = queue_inc_prod_n(&llq, n);
-		ret = arm_smmu_cmdq_poll_until_sync(smmu, &llq);
-		if (ret) {
-			dev_err_ratelimited(smmu->dev,
-					    "CMD_SYNC timeout at 0x%08x [hwprod 0x%08x, hwcons 0x%08x]\n",
-					    llq.prod,
-					    readl_relaxed(cmdq->q.prod_reg),
-					    readl_relaxed(cmdq->q.cons_reg));
-		}
+	spin_unlock_irqrestore(&smmu->cmdq.lock, flags);
 
-		/*
-		 * Try to unlock the cmq lock. This will fail if we're the last
-		 * reader, in which case we can safely update cmdq->q.llq.cons
-		 */
-		if (!arm_smmu_cmdq_shared_tryunlock(cmdq)) {
-			WRITE_ONCE(cmdq->q.llq.cons, llq.cons);
-			arm_smmu_cmdq_shared_unlock(cmdq);
-		}
-	}
-
-	local_irq_restore(flags);
-	return ret;
+	return __arm_smmu_sync_poll_msi(smmu, ent.sync.msidata);
 }
 
-static int arm_smmu_cmdq_issue_cmd(struct arm_smmu_device *smmu,
-				   struct arm_smmu_cmdq_ent *ent)
+static int __arm_smmu_cmdq_issue_sync(struct arm_smmu_device *smmu)
 {
 	u64 cmd[CMDQ_ENT_DWORDS];
+	unsigned long flags;
+	bool wfe = !!(smmu->features & ARM_SMMU_FEAT_SEV);
+	struct arm_smmu_cmdq_ent ent = { .opcode = CMDQ_OP_CMD_SYNC };
+	int ret;
 
-	if (arm_smmu_cmdq_build_cmd(cmd, ent)) {
-		dev_warn(smmu->dev, "ignoring unknown CMDQ opcode 0x%x\n",
-			 ent->opcode);
-		return -EINVAL;
-	}
+	arm_smmu_cmdq_build_cmd(cmd, &ent);
 
-	return arm_smmu_cmdq_issue_cmdlist(smmu, cmd, 1, false);
-}
+	spin_lock_irqsave(&smmu->cmdq.lock, flags);
+	arm_smmu_cmdq_insert_cmd(smmu, cmd);
+	ret = queue_poll_cons(&smmu->cmdq.q, true, wfe);
+	spin_unlock_irqrestore(&smmu->cmdq.lock, flags);
 
-static int arm_smmu_cmdq_issue_sync(struct arm_smmu_device *smmu)
-{
-	return arm_smmu_cmdq_issue_cmdlist(smmu, NULL, 0, true);
+	return ret;
 }
 
-static void arm_smmu_cmdq_batch_add(struct arm_smmu_device *smmu,
-				    struct arm_smmu_cmdq_batch *cmds,
-				    struct arm_smmu_cmdq_ent *cmd)
+static int arm_smmu_cmdq_issue_sync(struct arm_smmu_device *smmu)
 {
-	if (cmds->num == CMDQ_BATCH_ENTRIES) {
-		arm_smmu_cmdq_issue_cmdlist(smmu, cmds->cmds, cmds->num, false);
-		cmds->num = 0;
-	}
-	arm_smmu_cmdq_build_cmd(&cmds->cmds[cmds->num * CMDQ_ENT_DWORDS], cmd);
-	cmds->num++;
-}
+	int ret;
+	bool msi = (smmu->features & ARM_SMMU_FEAT_MSI) &&
+		   (smmu->features & ARM_SMMU_FEAT_COHERENCY);
 
-static int arm_smmu_cmdq_batch_submit(struct arm_smmu_device *smmu,
-				      struct arm_smmu_cmdq_batch *cmds)
-{
-	return arm_smmu_cmdq_issue_cmdlist(smmu, cmds->cmds, cmds->num, true);
+	ret = msi ? __arm_smmu_cmdq_issue_sync_msi(smmu)
+		  : __arm_smmu_cmdq_issue_sync(smmu);
+	if (ret)
+		dev_err_ratelimited(smmu->dev, "CMD_SYNC timeout\n");
+	return ret;
 }
 
 /* Context descriptor manipulation functions */
@@ -1536,7 +1117,6 @@ static void arm_smmu_sync_cd(struct arm_smmu_domain *smmu_domain,
 	size_t i;
 	unsigned long flags;
 	struct arm_smmu_master *master;
-	struct arm_smmu_cmdq_batch cmds = {};
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
 	struct arm_smmu_cmdq_ent cmd = {
 		.opcode	= CMDQ_OP_CFGI_CD,
@@ -1550,12 +1130,12 @@ static void arm_smmu_sync_cd(struct arm_smmu_domain *smmu_domain,
 	list_for_each_entry(master, &smmu_domain->devices, domain_head) {
 		for (i = 0; i < master->num_sids; i++) {
 			cmd.cfgi.sid = master->sids[i];
-			arm_smmu_cmdq_batch_add(smmu, &cmds, &cmd);
+			arm_smmu_cmdq_issue_cmd(smmu, &cmd);
 		}
 	}
 	spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
 
-	arm_smmu_cmdq_batch_submit(smmu, &cmds);
+	arm_smmu_cmdq_issue_sync(smmu);
 }
 
 static int arm_smmu_alloc_cd_leaf_table(struct arm_smmu_device *smmu,
@@ -2190,16 +1770,17 @@ arm_smmu_atc_inv_to_cmd(int ssid, unsigned long iova, size_t size,
 	cmd->atc.size	= log2_span;
 }
 
-static int arm_smmu_atc_inv_master(struct arm_smmu_master *master)
+static int arm_smmu_atc_inv_master(struct arm_smmu_master *master,
+				   struct arm_smmu_cmdq_ent *cmd)
 {
 	int i;
-	struct arm_smmu_cmdq_ent cmd;
 
-	arm_smmu_atc_inv_to_cmd(0, 0, 0, &cmd);
+	if (!master->ats_enabled)
+		return 0;
 
 	for (i = 0; i < master->num_sids; i++) {
-		cmd.atc.sid = master->sids[i];
-		arm_smmu_cmdq_issue_cmd(master->smmu, &cmd);
+		cmd->atc.sid = master->sids[i];
+		arm_smmu_cmdq_issue_cmd(master->smmu, cmd);
 	}
 
 	return arm_smmu_cmdq_issue_sync(master->smmu);
@@ -2208,11 +1789,10 @@ static int arm_smmu_atc_inv_master(struct arm_smmu_master *master)
 static int arm_smmu_atc_inv_domain(struct arm_smmu_domain *smmu_domain,
 				   int ssid, unsigned long iova, size_t size)
 {
-	int i;
+	int ret = 0;
 	unsigned long flags;
 	struct arm_smmu_cmdq_ent cmd;
 	struct arm_smmu_master *master;
-	struct arm_smmu_cmdq_batch cmds = {};
 
 	if (!(smmu_domain->smmu->features & ARM_SMMU_FEAT_ATS))
 		return 0;
@@ -2237,18 +1817,11 @@ static int arm_smmu_atc_inv_domain(struct arm_smmu_domain *smmu_domain,
 	arm_smmu_atc_inv_to_cmd(ssid, iova, size, &cmd);
 
 	spin_lock_irqsave(&smmu_domain->devices_lock, flags);
-	list_for_each_entry(master, &smmu_domain->devices, domain_head) {
-		if (!master->ats_enabled)
-			continue;
-
-		for (i = 0; i < master->num_sids; i++) {
-			cmd.atc.sid = master->sids[i];
-			arm_smmu_cmdq_batch_add(smmu_domain->smmu, &cmds, &cmd);
-		}
-	}
+	list_for_each_entry(master, &smmu_domain->devices, domain_head)
+		ret |= arm_smmu_atc_inv_master(master, &cmd);
 	spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
 
-	return arm_smmu_cmdq_batch_submit(smmu_domain->smmu, &cmds);
+	return ret ? -ETIMEDOUT : 0;
 }
 
 /* IO_PGTABLE API */
@@ -2270,26 +1843,23 @@ static void arm_smmu_tlb_inv_context(void *cookie)
 	/*
 	 * NOTE: when io-pgtable is in non-strict mode, we may get here with
 	 * PTEs previously cleared by unmaps on the current CPU not yet visible
-	 * to the SMMU. We are relying on the dma_wmb() implicit during cmd
-	 * insertion to guarantee those are observed before the TLBI. Do be
-	 * careful, 007.
+	 * to the SMMU. We are relying on the DSB implicit in
+	 * queue_sync_prod_out() to guarantee those are observed before the
+	 * TLBI. Do be careful, 007.
 	 */
 	arm_smmu_cmdq_issue_cmd(smmu, &cmd);
 	arm_smmu_cmdq_issue_sync(smmu);
-	arm_smmu_atc_inv_domain(smmu_domain, 0, 0, 0);
 }
 
-static void arm_smmu_tlb_inv_range(unsigned long iova, size_t size,
-				   size_t granule, bool leaf,
-				   struct arm_smmu_domain *smmu_domain)
+static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
+					  size_t granule, bool leaf, void *cookie)
 {
+	struct arm_smmu_domain *smmu_domain = cookie;
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
-	unsigned long start = iova, end = iova + size, num_pages = 0, tg = 0;
-	size_t inv_range = granule;
-	struct arm_smmu_cmdq_batch cmds = {};
 	struct arm_smmu_cmdq_ent cmd = {
 		.tlbi = {
 			.leaf	= leaf,
+			.addr	= iova,
 		},
 	};
 
@@ -2304,78 +1874,37 @@ static void arm_smmu_tlb_inv_range(unsigned long iova, size_t size,
 		cmd.tlbi.vmid	= smmu_domain->s2_cfg.vmid;
 	}
 
-	if (smmu->features & ARM_SMMU_FEAT_RANGE_INV) {
-		/* Get the leaf page size */
-		tg = __ffs(smmu_domain->domain.pgsize_bitmap);
-
-		/* Convert page size of 12,14,16 (log2) to 1,2,3 */
-		cmd.tlbi.tg = (tg - 10) / 2;
-
-		/* Determine what level the granule is at */
-		cmd.tlbi.ttl = 4 - ((ilog2(granule) - 3) / (tg - 3));
-
-		num_pages = size >> tg;
-	}
-
-	while (iova < end) {
-		if (smmu->features & ARM_SMMU_FEAT_RANGE_INV) {
-			/*
-			 * On each iteration of the loop, the range is 5 bits
-			 * worth of the aligned size remaining.
-			 * The range in pages is:
-			 *
-			 * range = (num_pages & (0x1f << __ffs(num_pages)))
-			 */
-			unsigned long scale, num;
-
-			/* Determine the power of 2 multiple number of pages */
-			scale = __ffs(num_pages);
-			cmd.tlbi.scale = scale;
-
-			/* Determine how many chunks of 2^scale size we have */
-			num = (num_pages >> scale) & CMDQ_TLBI_RANGE_NUM_MAX;
-			cmd.tlbi.num = num - 1;
-
-			/* range is num * 2^scale * pgsize */
-			inv_range = num << (scale + tg);
-
-			/* Clear out the lower order bits for the next iteration */
-			num_pages -= num << scale;
-		}
-
-		cmd.tlbi.addr = iova;
-		arm_smmu_cmdq_batch_add(smmu, &cmds, &cmd);
-		iova += inv_range;
-	}
-	arm_smmu_cmdq_batch_submit(smmu, &cmds);
-
-	/*
-	 * Unfortunately, this can't be leaf-only since we may have
-	 * zapped an entire table.
-	 */
-	arm_smmu_atc_inv_domain(smmu_domain, 0, start, size);
+	do {
+		arm_smmu_cmdq_issue_cmd(smmu, &cmd);
+		cmd.tlbi.addr += granule;
+	} while (size -= granule);
 }
 
 static void arm_smmu_tlb_inv_page_nosync(struct iommu_iotlb_gather *gather,
 					 unsigned long iova, size_t granule,
 					 void *cookie)
 {
-	struct arm_smmu_domain *smmu_domain = cookie;
-	struct iommu_domain *domain = &smmu_domain->domain;
-
-	iommu_iotlb_gather_add_page(domain, gather, iova, granule);
+	arm_smmu_tlb_inv_range_nosync(iova, granule, granule, true, cookie);
 }
 
 static void arm_smmu_tlb_inv_walk(unsigned long iova, size_t size,
 				  size_t granule, void *cookie)
 {
-	arm_smmu_tlb_inv_range(iova, size, granule, false, cookie);
+	struct arm_smmu_domain *smmu_domain = cookie;
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
+
+	arm_smmu_tlb_inv_range_nosync(iova, size, granule, false, cookie);
+	arm_smmu_cmdq_issue_sync(smmu);
 }
 
 static void arm_smmu_tlb_inv_leaf(unsigned long iova, size_t size,
 				  size_t granule, void *cookie)
 {
-	arm_smmu_tlb_inv_range(iova, size, granule, true, cookie);
+	struct arm_smmu_domain *smmu_domain = cookie;
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
+
+	arm_smmu_tlb_inv_range_nosync(iova, size, granule, true, cookie);
+	arm_smmu_cmdq_issue_sync(smmu);
 }
 
 static const struct iommu_flush_ops arm_smmu_flush_ops = {
@@ -2701,6 +2230,7 @@ static void arm_smmu_enable_ats(struct arm_smmu_master *master)
 
 static void arm_smmu_disable_ats(struct arm_smmu_master *master)
 {
+	struct arm_smmu_cmdq_ent cmd;
 	struct arm_smmu_domain *smmu_domain = master->domain;
 
 	if (!master->ats_enabled)
@@ -2712,7 +2242,8 @@ static void arm_smmu_disable_ats(struct arm_smmu_master *master)
 	 * ATC invalidation via the SMMU.
 	 */
 	wmb();
-	arm_smmu_atc_inv_master(master);
+	arm_smmu_atc_inv_to_cmd(0, 0, 0, &cmd);
+	arm_smmu_atc_inv_master(master, &cmd);
 	atomic_dec(&smmu_domain->nr_ats_masters);
 }
 
@@ -2856,13 +2387,18 @@ static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova,
 static size_t arm_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
 			     size_t size, struct iommu_iotlb_gather *gather)
 {
+	int ret;
 	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
 	struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops;
 
 	if (!ops)
 		return 0;
 
-	return ops->unmap(ops, iova, size, gather);
+	ret = ops->unmap(ops, iova, size, gather);
+	if (ret && arm_smmu_atc_inv_domain(smmu_domain, 0, iova, size))
+		return 0;
+
+	return ret;
 }
 
 static void arm_smmu_flush_iotlb_all(struct iommu_domain *domain)
@@ -2876,10 +2412,10 @@ static void arm_smmu_flush_iotlb_all(struct iommu_domain *domain)
 static void arm_smmu_iotlb_sync(struct iommu_domain *domain,
 				struct iommu_iotlb_gather *gather)
 {
-	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+	struct arm_smmu_device *smmu = to_smmu_domain(domain)->smmu;
 
-	arm_smmu_tlb_inv_range(gather->start, gather->end - gather->start,
-			       gather->pgsize, true, smmu_domain);
+	if (smmu)
+		arm_smmu_cmdq_issue_sync(smmu);
 }
 
 static phys_addr_t
@@ -3177,49 +2713,18 @@ static int arm_smmu_init_one_queue(struct arm_smmu_device *smmu,
 	return 0;
 }
 
-static void arm_smmu_cmdq_free_bitmap(void *data)
-{
-	unsigned long *bitmap = data;
-	bitmap_free(bitmap);
-}
-
-static int arm_smmu_cmdq_init(struct arm_smmu_device *smmu)
-{
-	int ret = 0;
-	struct arm_smmu_cmdq *cmdq = &smmu->cmdq;
-	unsigned int nents = 1 << cmdq->q.llq.max_n_shift;
-	atomic_long_t *bitmap;
-
-	atomic_set(&cmdq->owner_prod, 0);
-	atomic_set(&cmdq->lock, 0);
-
-	bitmap = (atomic_long_t *)bitmap_zalloc(nents, GFP_KERNEL);
-	if (!bitmap) {
-		dev_err(smmu->dev, "failed to allocate cmdq bitmap\n");
-		ret = -ENOMEM;
-	} else {
-		cmdq->valid_map = bitmap;
-		devm_add_action(smmu->dev, arm_smmu_cmdq_free_bitmap, bitmap);
-	}
-
-	return ret;
-}
-
 static int arm_smmu_init_queues(struct arm_smmu_device *smmu)
 {
 	int ret;
 
 	/* cmdq */
+	spin_lock_init(&smmu->cmdq.lock);
 	ret = arm_smmu_init_one_queue(smmu, &smmu->cmdq.q, ARM_SMMU_CMDQ_PROD,
 				      ARM_SMMU_CMDQ_CONS, CMDQ_ENT_DWORDS,
 				      "cmdq");
 	if (ret)
 		return ret;
 
-	ret = arm_smmu_cmdq_init(smmu);
-	if (ret)
-		return ret;
-
 	/* evtq */
 	ret = arm_smmu_init_one_queue(smmu, &smmu->evtq.q, ARM_SMMU_EVTQ_PROD,
 				      ARM_SMMU_EVTQ_CONS, EVTQ_ENT_DWORDS,
@@ -3800,15 +3305,9 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 	/* Queue sizes, capped to ensure natural alignment */
 	smmu->cmdq.q.llq.max_n_shift = min_t(u32, CMDQ_MAX_SZ_SHIFT,
 					     FIELD_GET(IDR1_CMDQS, reg));
-	if (smmu->cmdq.q.llq.max_n_shift <= ilog2(CMDQ_BATCH_ENTRIES)) {
-		/*
-		 * We don't support splitting up batches, so one batch of
-		 * commands plus an extra sync needs to fit inside the command
-		 * queue. There's also no way we can handle the weird alignment
-		 * restrictions on the base pointer for a unit-length queue.
-		 */
-		dev_err(smmu->dev, "command queue size <= %d entries not supported\n",
-			CMDQ_BATCH_ENTRIES);
+	if (!smmu->cmdq.q.llq.max_n_shift) {
+		/* Odd alignment restrictions on the base, so ignore for now */
+		dev_err(smmu->dev, "unit-length command queue not supported\n");
 		return -ENXIO;
 	}
 
@@ -3828,11 +3327,6 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 	if (smmu->sid_bits <= STRTAB_SPLIT)
 		smmu->features &= ~ARM_SMMU_FEAT_2_LVL_STRTAB;
 
-	/* IDR3 */
-	reg = readl_relaxed(smmu->base + ARM_SMMU_IDR3);
-	if (FIELD_GET(IDR3_RIL, reg))
-		smmu->features |= ARM_SMMU_FEAT_RANGE_INV;
-
 	/* IDR5 */
 	reg = readl_relaxed(smmu->base + ARM_SMMU_IDR5);
 
-- 
2.17.1



^ permalink raw reply related	[flat|nested] 24+ messages in thread

* [PATCH v5 03/10] xen/arm: smmuv3: Revert patch related to XArray
  2021-01-20 14:52 [PATCH v5 00/10] xen/arm: Add support for SMMUv3 driver Rahul Singh
  2021-01-20 14:52 ` [PATCH v5 01/10] xen/arm: smmuv3: Import the SMMUv3 driver from Linux Rahul Singh
  2021-01-20 14:52 ` [PATCH v5 02/10] xen/arm: Revert atomic operation related command-queue insertion patch Rahul Singh
@ 2021-01-20 14:52 ` Rahul Singh
  2021-01-20 14:52 ` [PATCH v5 04/10] xen/arm: smmuv3: Remove support for Stage-1 translation on SMMUv3 Rahul Singh
                   ` (6 subsequent siblings)
  9 siblings, 0 replies; 24+ messages in thread
From: Rahul Singh @ 2021-01-20 14:52 UTC (permalink / raw)
  To: xen-devel
  Cc: bertrand.marquis, rahul.singh, Stefano Stabellini, Julien Grall,
	Volodymyr Babchuk

XArray is not implemented in XEN revert the patch that introduce the
XArray code in SMMUv3 driver.

XArray is added in preparation for sharing some ASIDs with the CPU,

As XEN support only Stage-2 translation, ASID is used for Stage-1
translation there is no consequences of reverting this patch for XEN.

Once XArray is implemented in XEN this patch can be added in XEN if XEN
supports Stage-1 translation.

Reverted the commit 0299a1a81ca056e79c1a7fb751f936ec0d5c7afe

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
Changes since v2:
- Added consequences of reverting this patch in commit message
Changes since v3: No changes
Changes since v4: No changes
---
---
 xen/drivers/passthrough/arm/smmu-v3.c | 27 +++++++++------------------
 1 file changed, 9 insertions(+), 18 deletions(-)

diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
index 8b7747ed38..7b29ead48c 100644
--- a/xen/drivers/passthrough/arm/smmu-v3.c
+++ b/xen/drivers/passthrough/arm/smmu-v3.c
@@ -625,6 +625,7 @@ struct arm_smmu_device {
 
 #define ARM_SMMU_MAX_ASIDS		(1 << 16)
 	unsigned int			asid_bits;
+	DECLARE_BITMAP(asid_map, ARM_SMMU_MAX_ASIDS);
 
 #define ARM_SMMU_MAX_VMIDS		(1 << 16)
 	unsigned int			vmid_bits;
@@ -690,8 +691,6 @@ struct arm_smmu_option_prop {
 	const char *prop;
 };
 
-static DEFINE_XARRAY_ALLOC1(asid_xa);
-
 static struct arm_smmu_option_prop arm_smmu_options[] = {
 	{ ARM_SMMU_OPT_SKIP_PREFETCH, "hisilicon,broken-prefetch-cmd" },
 	{ ARM_SMMU_OPT_PAGE0_REGS_ONLY, "cavium,cn9900-broken-page1-regspace"},
@@ -1346,14 +1345,6 @@ static void arm_smmu_free_cd_tables(struct arm_smmu_domain *smmu_domain)
 	cdcfg->cdtab = NULL;
 }
 
-static void arm_smmu_free_asid(struct arm_smmu_ctx_desc *cd)
-{
-	if (!cd->asid)
-		return;
-
-	xa_erase(&asid_xa, cd->asid);
-}
-
 /* Stream table manipulation functions */
 static void
 arm_smmu_write_strtab_l1_desc(__le64 *dst, struct arm_smmu_strtab_l1_desc *desc)
@@ -1988,9 +1979,10 @@ static void arm_smmu_domain_free(struct iommu_domain *domain)
 	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
 		struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
 
-		if (cfg->cdcfg.cdtab)
+		if (cfg->cdcfg.cdtab) {
 			arm_smmu_free_cd_tables(smmu_domain);
-		arm_smmu_free_asid(&cfg->cd);
+			arm_smmu_bitmap_free(smmu->asid_map, cfg->cd.asid);
+		}
 	} else {
 		struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
 		if (cfg->vmid)
@@ -2005,15 +1997,14 @@ static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,
 				       struct io_pgtable_cfg *pgtbl_cfg)
 {
 	int ret;
-	u32 asid;
+	int asid;
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
 	struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
 	typeof(&pgtbl_cfg->arm_lpae_s1_cfg.tcr) tcr = &pgtbl_cfg->arm_lpae_s1_cfg.tcr;
 
-	ret = xa_alloc(&asid_xa, &asid, &cfg->cd,
-		       XA_LIMIT(1, (1 << smmu->asid_bits) - 1), GFP_KERNEL);
-	if (ret)
-		return ret;
+	asid = arm_smmu_bitmap_alloc(smmu->asid_map, smmu->asid_bits);
+	if (asid < 0)
+		return asid;
 
 	cfg->s1cdmax = master->ssid_bits;
 
@@ -2046,7 +2037,7 @@ static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,
 out_free_cd_tables:
 	arm_smmu_free_cd_tables(smmu_domain);
 out_free_asid:
-	arm_smmu_free_asid(&cfg->cd);
+	arm_smmu_bitmap_free(smmu->asid_map, asid);
 	return ret;
 }
 
-- 
2.17.1



^ permalink raw reply related	[flat|nested] 24+ messages in thread

* [PATCH v5 04/10] xen/arm: smmuv3: Remove support for Stage-1 translation on SMMUv3.
  2021-01-20 14:52 [PATCH v5 00/10] xen/arm: Add support for SMMUv3 driver Rahul Singh
                   ` (2 preceding siblings ...)
  2021-01-20 14:52 ` [PATCH v5 03/10] xen/arm: smmuv3: Revert patch related to XArray Rahul Singh
@ 2021-01-20 14:52 ` Rahul Singh
  2021-01-20 14:52 ` [PATCH v5 05/10] xen/arm: smmuv3: Remove Linux specific code that is not usable in XEN Rahul Singh
                   ` (5 subsequent siblings)
  9 siblings, 0 replies; 24+ messages in thread
From: Rahul Singh @ 2021-01-20 14:52 UTC (permalink / raw)
  To: xen-devel
  Cc: bertrand.marquis, rahul.singh, Stefano Stabellini, Julien Grall,
	Volodymyr Babchuk

Linux SMMUv3 driver supports both Stage-1 and Stage-2 translations.
As of now only Stage-2 translation support has been tested.

Once Stage-1 translation support is tested this patch can be added.

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
Changes since v2: No changes
Changes since v3: No changes
Changes since v4: No changes
---
---
 xen/drivers/passthrough/arm/smmu-v3.c | 468 +-------------------------
 1 file changed, 15 insertions(+), 453 deletions(-)

diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
index 7b29ead48c..869f38b753 100644
--- a/xen/drivers/passthrough/arm/smmu-v3.c
+++ b/xen/drivers/passthrough/arm/smmu-v3.c
@@ -449,19 +449,14 @@ struct arm_smmu_cmdq_ent {
 
 		#define CMDQ_OP_CFGI_STE	0x3
 		#define CMDQ_OP_CFGI_ALL	0x4
-		#define CMDQ_OP_CFGI_CD		0x5
-		#define CMDQ_OP_CFGI_CD_ALL	0x6
 		struct {
 			u32			sid;
-			u32			ssid;
 			union {
 				bool		leaf;
 				u8		span;
 			};
 		} cfgi;
 
-		#define CMDQ_OP_TLBI_NH_ASID	0x11
-		#define CMDQ_OP_TLBI_NH_VA	0x12
 		#define CMDQ_OP_TLBI_EL2_ALL	0x20
 		#define CMDQ_OP_TLBI_S12_VMALL	0x28
 		#define CMDQ_OP_TLBI_S2_IPA	0x2a
@@ -541,32 +536,6 @@ struct arm_smmu_strtab_l1_desc {
 	dma_addr_t			l2ptr_dma;
 };
 
-struct arm_smmu_ctx_desc {
-	u16				asid;
-	u64				ttbr;
-	u64				tcr;
-	u64				mair;
-};
-
-struct arm_smmu_l1_ctx_desc {
-	__le64				*l2ptr;
-	dma_addr_t			l2ptr_dma;
-};
-
-struct arm_smmu_ctx_desc_cfg {
-	__le64				*cdtab;
-	dma_addr_t			cdtab_dma;
-	struct arm_smmu_l1_ctx_desc	*l1_desc;
-	unsigned int			num_l1_ents;
-};
-
-struct arm_smmu_s1_cfg {
-	struct arm_smmu_ctx_desc_cfg	cdcfg;
-	struct arm_smmu_ctx_desc	cd;
-	u8				s1fmt;
-	u8				s1cdmax;
-};
-
 struct arm_smmu_s2_cfg {
 	u16				vmid;
 	u64				vttbr;
@@ -623,15 +592,10 @@ struct arm_smmu_device {
 	unsigned long			oas; /* PA */
 	unsigned long			pgsize_bitmap;
 
-#define ARM_SMMU_MAX_ASIDS		(1 << 16)
-	unsigned int			asid_bits;
-	DECLARE_BITMAP(asid_map, ARM_SMMU_MAX_ASIDS);
-
 #define ARM_SMMU_MAX_VMIDS		(1 << 16)
 	unsigned int			vmid_bits;
 	DECLARE_BITMAP(vmid_map, ARM_SMMU_MAX_VMIDS);
 
-	unsigned int			ssid_bits;
 	unsigned int			sid_bits;
 
 	struct arm_smmu_strtab_cfg	strtab_cfg;
@@ -655,7 +619,6 @@ struct arm_smmu_master {
 	u32				*sids;
 	unsigned int			num_sids;
 	bool				ats_enabled;
-	unsigned int			ssid_bits;
 };
 
 /* SMMU private data for an IOMMU domain */
@@ -675,10 +638,7 @@ struct arm_smmu_domain {
 	atomic_t			nr_ats_masters;
 
 	enum arm_smmu_domain_stage	stage;
-	union {
-		struct arm_smmu_s1_cfg	s1_cfg;
-		struct arm_smmu_s2_cfg	s2_cfg;
-	};
+	struct arm_smmu_s2_cfg	s2_cfg;
 
 	struct iommu_domain		domain;
 
@@ -869,34 +829,19 @@ static int arm_smmu_cmdq_build_cmd(u64 *cmd, struct arm_smmu_cmdq_ent *ent)
 		cmd[1] |= FIELD_PREP(CMDQ_PREFETCH_1_SIZE, ent->prefetch.size);
 		cmd[1] |= ent->prefetch.addr & CMDQ_PREFETCH_1_ADDR_MASK;
 		break;
-	case CMDQ_OP_CFGI_CD:
-		cmd[0] |= FIELD_PREP(CMDQ_CFGI_0_SSID, ent->cfgi.ssid);
-		/* Fallthrough */
 	case CMDQ_OP_CFGI_STE:
 		cmd[0] |= FIELD_PREP(CMDQ_CFGI_0_SID, ent->cfgi.sid);
 		cmd[1] |= FIELD_PREP(CMDQ_CFGI_1_LEAF, ent->cfgi.leaf);
 		break;
-	case CMDQ_OP_CFGI_CD_ALL:
-		cmd[0] |= FIELD_PREP(CMDQ_CFGI_0_SID, ent->cfgi.sid);
-		break;
 	case CMDQ_OP_CFGI_ALL:
 		/* Cover the entire SID range */
 		cmd[1] |= FIELD_PREP(CMDQ_CFGI_1_RANGE, 31);
 		break;
-	case CMDQ_OP_TLBI_NH_VA:
-		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_VMID, ent->tlbi.vmid);
-		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_ASID, ent->tlbi.asid);
-		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_LEAF, ent->tlbi.leaf);
-		cmd[1] |= ent->tlbi.addr & CMDQ_TLBI_1_VA_MASK;
-		break;
 	case CMDQ_OP_TLBI_S2_IPA:
 		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_VMID, ent->tlbi.vmid);
 		cmd[1] |= FIELD_PREP(CMDQ_TLBI_1_LEAF, ent->tlbi.leaf);
 		cmd[1] |= ent->tlbi.addr & CMDQ_TLBI_1_IPA_MASK;
 		break;
-	case CMDQ_OP_TLBI_NH_ASID:
-		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_ASID, ent->tlbi.asid);
-		/* Fallthrough */
 	case CMDQ_OP_TLBI_S12_VMALL:
 		cmd[0] |= FIELD_PREP(CMDQ_TLBI_0_VMID, ent->tlbi.vmid);
 		break;
@@ -1109,242 +1054,6 @@ static int arm_smmu_cmdq_issue_sync(struct arm_smmu_device *smmu)
 	return ret;
 }
 
-/* Context descriptor manipulation functions */
-static void arm_smmu_sync_cd(struct arm_smmu_domain *smmu_domain,
-			     int ssid, bool leaf)
-{
-	size_t i;
-	unsigned long flags;
-	struct arm_smmu_master *master;
-	struct arm_smmu_device *smmu = smmu_domain->smmu;
-	struct arm_smmu_cmdq_ent cmd = {
-		.opcode	= CMDQ_OP_CFGI_CD,
-		.cfgi	= {
-			.ssid	= ssid,
-			.leaf	= leaf,
-		},
-	};
-
-	spin_lock_irqsave(&smmu_domain->devices_lock, flags);
-	list_for_each_entry(master, &smmu_domain->devices, domain_head) {
-		for (i = 0; i < master->num_sids; i++) {
-			cmd.cfgi.sid = master->sids[i];
-			arm_smmu_cmdq_issue_cmd(smmu, &cmd);
-		}
-	}
-	spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
-
-	arm_smmu_cmdq_issue_sync(smmu);
-}
-
-static int arm_smmu_alloc_cd_leaf_table(struct arm_smmu_device *smmu,
-					struct arm_smmu_l1_ctx_desc *l1_desc)
-{
-	size_t size = CTXDESC_L2_ENTRIES * (CTXDESC_CD_DWORDS << 3);
-
-	l1_desc->l2ptr = dmam_alloc_coherent(smmu->dev, size,
-					     &l1_desc->l2ptr_dma, GFP_KERNEL);
-	if (!l1_desc->l2ptr) {
-		dev_warn(smmu->dev,
-			 "failed to allocate context descriptor table\n");
-		return -ENOMEM;
-	}
-	return 0;
-}
-
-static void arm_smmu_write_cd_l1_desc(__le64 *dst,
-				      struct arm_smmu_l1_ctx_desc *l1_desc)
-{
-	u64 val = (l1_desc->l2ptr_dma & CTXDESC_L1_DESC_L2PTR_MASK) |
-		  CTXDESC_L1_DESC_V;
-
-	/* See comment in arm_smmu_write_ctx_desc() */
-	WRITE_ONCE(*dst, cpu_to_le64(val));
-}
-
-static __le64 *arm_smmu_get_cd_ptr(struct arm_smmu_domain *smmu_domain,
-				   u32 ssid)
-{
-	__le64 *l1ptr;
-	unsigned int idx;
-	struct arm_smmu_l1_ctx_desc *l1_desc;
-	struct arm_smmu_device *smmu = smmu_domain->smmu;
-	struct arm_smmu_ctx_desc_cfg *cdcfg = &smmu_domain->s1_cfg.cdcfg;
-
-	if (smmu_domain->s1_cfg.s1fmt == STRTAB_STE_0_S1FMT_LINEAR)
-		return cdcfg->cdtab + ssid * CTXDESC_CD_DWORDS;
-
-	idx = ssid >> CTXDESC_SPLIT;
-	l1_desc = &cdcfg->l1_desc[idx];
-	if (!l1_desc->l2ptr) {
-		if (arm_smmu_alloc_cd_leaf_table(smmu, l1_desc))
-			return NULL;
-
-		l1ptr = cdcfg->cdtab + idx * CTXDESC_L1_DESC_DWORDS;
-		arm_smmu_write_cd_l1_desc(l1ptr, l1_desc);
-		/* An invalid L1CD can be cached */
-		arm_smmu_sync_cd(smmu_domain, ssid, false);
-	}
-	idx = ssid & (CTXDESC_L2_ENTRIES - 1);
-	return l1_desc->l2ptr + idx * CTXDESC_CD_DWORDS;
-}
-
-static int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain,
-				   int ssid, struct arm_smmu_ctx_desc *cd)
-{
-	/*
-	 * This function handles the following cases:
-	 *
-	 * (1) Install primary CD, for normal DMA traffic (SSID = 0).
-	 * (2) Install a secondary CD, for SID+SSID traffic.
-	 * (3) Update ASID of a CD. Atomically write the first 64 bits of the
-	 *     CD, then invalidate the old entry and mappings.
-	 * (4) Remove a secondary CD.
-	 */
-	u64 val;
-	bool cd_live;
-	__le64 *cdptr;
-	struct arm_smmu_device *smmu = smmu_domain->smmu;
-
-	if (WARN_ON(ssid >= (1 << smmu_domain->s1_cfg.s1cdmax)))
-		return -E2BIG;
-
-	cdptr = arm_smmu_get_cd_ptr(smmu_domain, ssid);
-	if (!cdptr)
-		return -ENOMEM;
-
-	val = le64_to_cpu(cdptr[0]);
-	cd_live = !!(val & CTXDESC_CD_0_V);
-
-	if (!cd) { /* (4) */
-		val = 0;
-	} else if (cd_live) { /* (3) */
-		val &= ~CTXDESC_CD_0_ASID;
-		val |= FIELD_PREP(CTXDESC_CD_0_ASID, cd->asid);
-		/*
-		 * Until CD+TLB invalidation, both ASIDs may be used for tagging
-		 * this substream's traffic
-		 */
-	} else { /* (1) and (2) */
-		cdptr[1] = cpu_to_le64(cd->ttbr & CTXDESC_CD_1_TTB0_MASK);
-		cdptr[2] = 0;
-		cdptr[3] = cpu_to_le64(cd->mair);
-
-		/*
-		 * STE is live, and the SMMU might read dwords of this CD in any
-		 * order. Ensure that it observes valid values before reading
-		 * V=1.
-		 */
-		arm_smmu_sync_cd(smmu_domain, ssid, true);
-
-		val = cd->tcr |
-#ifdef __BIG_ENDIAN
-			CTXDESC_CD_0_ENDI |
-#endif
-			CTXDESC_CD_0_R | CTXDESC_CD_0_A | CTXDESC_CD_0_ASET |
-			CTXDESC_CD_0_AA64 |
-			FIELD_PREP(CTXDESC_CD_0_ASID, cd->asid) |
-			CTXDESC_CD_0_V;
-
-		/* STALL_MODEL==0b10 && CD.S==0 is ILLEGAL */
-		if (smmu->features & ARM_SMMU_FEAT_STALL_FORCE)
-			val |= CTXDESC_CD_0_S;
-	}
-
-	/*
-	 * The SMMU accesses 64-bit values atomically. See IHI0070Ca 3.21.3
-	 * "Configuration structures and configuration invalidation completion"
-	 *
-	 *   The size of single-copy atomic reads made by the SMMU is
-	 *   IMPLEMENTATION DEFINED but must be at least 64 bits. Any single
-	 *   field within an aligned 64-bit span of a structure can be altered
-	 *   without first making the structure invalid.
-	 */
-	WRITE_ONCE(cdptr[0], cpu_to_le64(val));
-	arm_smmu_sync_cd(smmu_domain, ssid, true);
-	return 0;
-}
-
-static int arm_smmu_alloc_cd_tables(struct arm_smmu_domain *smmu_domain)
-{
-	int ret;
-	size_t l1size;
-	size_t max_contexts;
-	struct arm_smmu_device *smmu = smmu_domain->smmu;
-	struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
-	struct arm_smmu_ctx_desc_cfg *cdcfg = &cfg->cdcfg;
-
-	max_contexts = 1 << cfg->s1cdmax;
-
-	if (!(smmu->features & ARM_SMMU_FEAT_2_LVL_CDTAB) ||
-	    max_contexts <= CTXDESC_L2_ENTRIES) {
-		cfg->s1fmt = STRTAB_STE_0_S1FMT_LINEAR;
-		cdcfg->num_l1_ents = max_contexts;
-
-		l1size = max_contexts * (CTXDESC_CD_DWORDS << 3);
-	} else {
-		cfg->s1fmt = STRTAB_STE_0_S1FMT_64K_L2;
-		cdcfg->num_l1_ents = DIV_ROUND_UP(max_contexts,
-						  CTXDESC_L2_ENTRIES);
-
-		cdcfg->l1_desc = devm_kcalloc(smmu->dev, cdcfg->num_l1_ents,
-					      sizeof(*cdcfg->l1_desc),
-					      GFP_KERNEL);
-		if (!cdcfg->l1_desc)
-			return -ENOMEM;
-
-		l1size = cdcfg->num_l1_ents * (CTXDESC_L1_DESC_DWORDS << 3);
-	}
-
-	cdcfg->cdtab = dmam_alloc_coherent(smmu->dev, l1size, &cdcfg->cdtab_dma,
-					   GFP_KERNEL);
-	if (!cdcfg->cdtab) {
-		dev_warn(smmu->dev, "failed to allocate context descriptor\n");
-		ret = -ENOMEM;
-		goto err_free_l1;
-	}
-
-	return 0;
-
-err_free_l1:
-	if (cdcfg->l1_desc) {
-		devm_kfree(smmu->dev, cdcfg->l1_desc);
-		cdcfg->l1_desc = NULL;
-	}
-	return ret;
-}
-
-static void arm_smmu_free_cd_tables(struct arm_smmu_domain *smmu_domain)
-{
-	int i;
-	size_t size, l1size;
-	struct arm_smmu_device *smmu = smmu_domain->smmu;
-	struct arm_smmu_ctx_desc_cfg *cdcfg = &smmu_domain->s1_cfg.cdcfg;
-
-	if (cdcfg->l1_desc) {
-		size = CTXDESC_L2_ENTRIES * (CTXDESC_CD_DWORDS << 3);
-
-		for (i = 0; i < cdcfg->num_l1_ents; i++) {
-			if (!cdcfg->l1_desc[i].l2ptr)
-				continue;
-
-			dmam_free_coherent(smmu->dev, size,
-					   cdcfg->l1_desc[i].l2ptr,
-					   cdcfg->l1_desc[i].l2ptr_dma);
-		}
-		devm_kfree(smmu->dev, cdcfg->l1_desc);
-		cdcfg->l1_desc = NULL;
-
-		l1size = cdcfg->num_l1_ents * (CTXDESC_L1_DESC_DWORDS << 3);
-	} else {
-		l1size = cdcfg->num_l1_ents * (CTXDESC_CD_DWORDS << 3);
-	}
-
-	dmam_free_coherent(smmu->dev, l1size, cdcfg->cdtab, cdcfg->cdtab_dma);
-	cdcfg->cdtab_dma = 0;
-	cdcfg->cdtab = NULL;
-}
-
 /* Stream table manipulation functions */
 static void
 arm_smmu_write_strtab_l1_desc(__le64 *dst, struct arm_smmu_strtab_l1_desc *desc)
@@ -1394,7 +1103,6 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
 	u64 val = le64_to_cpu(dst[0]);
 	bool ste_live = false;
 	struct arm_smmu_device *smmu = NULL;
-	struct arm_smmu_s1_cfg *s1_cfg = NULL;
 	struct arm_smmu_s2_cfg *s2_cfg = NULL;
 	struct arm_smmu_domain *smmu_domain = NULL;
 	struct arm_smmu_cmdq_ent prefetch_cmd = {
@@ -1409,25 +1117,13 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
 		smmu = master->smmu;
 	}
 
-	if (smmu_domain) {
-		switch (smmu_domain->stage) {
-		case ARM_SMMU_DOMAIN_S1:
-			s1_cfg = &smmu_domain->s1_cfg;
-			break;
-		case ARM_SMMU_DOMAIN_S2:
-		case ARM_SMMU_DOMAIN_NESTED:
-			s2_cfg = &smmu_domain->s2_cfg;
-			break;
-		default:
-			break;
-		}
-	}
+	if (smmu_domain)
+		s2_cfg = &smmu_domain->s2_cfg;
 
 	if (val & STRTAB_STE_0_V) {
 		switch (FIELD_GET(STRTAB_STE_0_CFG, val)) {
 		case STRTAB_STE_0_CFG_BYPASS:
 			break;
-		case STRTAB_STE_0_CFG_S1_TRANS:
 		case STRTAB_STE_0_CFG_S2_TRANS:
 			ste_live = true;
 			break;
@@ -1443,7 +1139,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
 	val = STRTAB_STE_0_V;
 
 	/* Bypass/fault */
-	if (!smmu_domain || !(s1_cfg || s2_cfg)) {
+	if (!smmu_domain || !(s2_cfg)) {
 		if (!smmu_domain && disable_bypass)
 			val |= FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_ABORT);
 		else
@@ -1462,25 +1158,6 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
 		return;
 	}
 
-	if (s1_cfg) {
-		BUG_ON(ste_live);
-		dst[1] = cpu_to_le64(
-			 FIELD_PREP(STRTAB_STE_1_S1DSS, STRTAB_STE_1_S1DSS_SSID0) |
-			 FIELD_PREP(STRTAB_STE_1_S1CIR, STRTAB_STE_1_S1C_CACHE_WBRA) |
-			 FIELD_PREP(STRTAB_STE_1_S1COR, STRTAB_STE_1_S1C_CACHE_WBRA) |
-			 FIELD_PREP(STRTAB_STE_1_S1CSH, ARM_SMMU_SH_ISH) |
-			 FIELD_PREP(STRTAB_STE_1_STRW, STRTAB_STE_1_STRW_NSEL1));
-
-		if (smmu->features & ARM_SMMU_FEAT_STALLS &&
-		   !(smmu->features & ARM_SMMU_FEAT_STALL_FORCE))
-			dst[1] |= cpu_to_le64(STRTAB_STE_1_S1STALLD);
-
-		val |= (s1_cfg->cdcfg.cdtab_dma & STRTAB_STE_0_S1CTXPTR_MASK) |
-			FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_S1_TRANS) |
-			FIELD_PREP(STRTAB_STE_0_S1CDMAX, s1_cfg->s1cdmax) |
-			FIELD_PREP(STRTAB_STE_0_S1FMT, s1_cfg->s1fmt);
-	}
-
 	if (s2_cfg) {
 		BUG_ON(ste_live);
 		dst[2] = cpu_to_le64(
@@ -1502,7 +1179,6 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
 						 STRTAB_STE_1_EATS_TRANS));
 
 	arm_smmu_sync_ste_for_sid(smmu, sid);
-	/* See comment in arm_smmu_write_ctx_desc() */
 	WRITE_ONCE(dst[0], cpu_to_le64(val));
 	arm_smmu_sync_ste_for_sid(smmu, sid);
 
@@ -1822,14 +1498,8 @@ static void arm_smmu_tlb_inv_context(void *cookie)
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
 	struct arm_smmu_cmdq_ent cmd;
 
-	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
-		cmd.opcode	= CMDQ_OP_TLBI_NH_ASID;
-		cmd.tlbi.asid	= smmu_domain->s1_cfg.cd.asid;
-		cmd.tlbi.vmid	= 0;
-	} else {
-		cmd.opcode	= CMDQ_OP_TLBI_S12_VMALL;
-		cmd.tlbi.vmid	= smmu_domain->s2_cfg.vmid;
-	}
+	cmd.opcode	= CMDQ_OP_TLBI_S12_VMALL;
+	cmd.tlbi.vmid	= smmu_domain->s2_cfg.vmid;
 
 	/*
 	 * NOTE: when io-pgtable is in non-strict mode, we may get here with
@@ -1857,13 +1527,8 @@ static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
 	if (!size)
 		return;
 
-	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
-		cmd.opcode	= CMDQ_OP_TLBI_NH_VA;
-		cmd.tlbi.asid	= smmu_domain->s1_cfg.cd.asid;
-	} else {
-		cmd.opcode	= CMDQ_OP_TLBI_S2_IPA;
-		cmd.tlbi.vmid	= smmu_domain->s2_cfg.vmid;
-	}
+	cmd.opcode	= CMDQ_OP_TLBI_S2_IPA;
+	cmd.tlbi.vmid	= smmu_domain->s2_cfg.vmid;
 
 	do {
 		arm_smmu_cmdq_issue_cmd(smmu, &cmd);
@@ -1971,75 +1636,17 @@ static void arm_smmu_domain_free(struct iommu_domain *domain)
 {
 	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
+	struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
 
 	iommu_put_dma_cookie(domain);
 	free_io_pgtable_ops(smmu_domain->pgtbl_ops);
 
-	/* Free the CD and ASID, if we allocated them */
-	if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
-		struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
-
-		if (cfg->cdcfg.cdtab) {
-			arm_smmu_free_cd_tables(smmu_domain);
-			arm_smmu_bitmap_free(smmu->asid_map, cfg->cd.asid);
-		}
-	} else {
-		struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
-		if (cfg->vmid)
-			arm_smmu_bitmap_free(smmu->vmid_map, cfg->vmid);
-	}
+	if (cfg->vmid)
+		arm_smmu_bitmap_free(smmu->vmid_map, cfg->vmid);
 
 	kfree(smmu_domain);
 }
 
-static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,
-				       struct arm_smmu_master *master,
-				       struct io_pgtable_cfg *pgtbl_cfg)
-{
-	int ret;
-	int asid;
-	struct arm_smmu_device *smmu = smmu_domain->smmu;
-	struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
-	typeof(&pgtbl_cfg->arm_lpae_s1_cfg.tcr) tcr = &pgtbl_cfg->arm_lpae_s1_cfg.tcr;
-
-	asid = arm_smmu_bitmap_alloc(smmu->asid_map, smmu->asid_bits);
-	if (asid < 0)
-		return asid;
-
-	cfg->s1cdmax = master->ssid_bits;
-
-	ret = arm_smmu_alloc_cd_tables(smmu_domain);
-	if (ret)
-		goto out_free_asid;
-
-	cfg->cd.asid	= (u16)asid;
-	cfg->cd.ttbr	= pgtbl_cfg->arm_lpae_s1_cfg.ttbr;
-	cfg->cd.tcr	= FIELD_PREP(CTXDESC_CD_0_TCR_T0SZ, tcr->tsz) |
-			  FIELD_PREP(CTXDESC_CD_0_TCR_TG0, tcr->tg) |
-			  FIELD_PREP(CTXDESC_CD_0_TCR_IRGN0, tcr->irgn) |
-			  FIELD_PREP(CTXDESC_CD_0_TCR_ORGN0, tcr->orgn) |
-			  FIELD_PREP(CTXDESC_CD_0_TCR_SH0, tcr->sh) |
-			  FIELD_PREP(CTXDESC_CD_0_TCR_IPS, tcr->ips) |
-			  CTXDESC_CD_0_TCR_EPD1 | CTXDESC_CD_0_AA64;
-	cfg->cd.mair	= pgtbl_cfg->arm_lpae_s1_cfg.mair;
-
-	/*
-	 * Note that this will end up calling arm_smmu_sync_cd() before
-	 * the master has been added to the devices list for this domain.
-	 * This isn't an issue because the STE hasn't been installed yet.
-	 */
-	ret = arm_smmu_write_ctx_desc(smmu_domain, 0, &cfg->cd);
-	if (ret)
-		goto out_free_cd_tables;
-
-	return 0;
-
-out_free_cd_tables:
-	arm_smmu_free_cd_tables(smmu_domain);
-out_free_asid:
-	arm_smmu_bitmap_free(smmu->asid_map, asid);
-	return ret;
-}
 
 static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
 				       struct arm_smmu_master *master,
@@ -2075,9 +1682,6 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain,
 	enum io_pgtable_fmt fmt;
 	struct io_pgtable_cfg pgtbl_cfg;
 	struct io_pgtable_ops *pgtbl_ops;
-	int (*finalise_stage_fn)(struct arm_smmu_domain *,
-				 struct arm_smmu_master *,
-				 struct io_pgtable_cfg *);
 	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
 
@@ -2087,29 +1691,8 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain,
 	}
 
 	/* Restrict the stage to what we can actually support */
-	if (!(smmu->features & ARM_SMMU_FEAT_TRANS_S1))
-		smmu_domain->stage = ARM_SMMU_DOMAIN_S2;
-	if (!(smmu->features & ARM_SMMU_FEAT_TRANS_S2))
-		smmu_domain->stage = ARM_SMMU_DOMAIN_S1;
-
-	switch (smmu_domain->stage) {
-	case ARM_SMMU_DOMAIN_S1:
-		ias = (smmu->features & ARM_SMMU_FEAT_VAX) ? 52 : 48;
-		ias = min_t(unsigned long, ias, VA_BITS);
-		oas = smmu->ias;
-		fmt = ARM_64_LPAE_S1;
-		finalise_stage_fn = arm_smmu_domain_finalise_s1;
-		break;
-	case ARM_SMMU_DOMAIN_NESTED:
-	case ARM_SMMU_DOMAIN_S2:
-		ias = smmu->ias;
-		oas = smmu->oas;
-		fmt = ARM_64_LPAE_S2;
-		finalise_stage_fn = arm_smmu_domain_finalise_s2;
-		break;
-	default:
-		return -EINVAL;
-	}
+	smmu_domain->stage = ARM_SMMU_DOMAIN_S2;
+
 
 	pgtbl_cfg = (struct io_pgtable_cfg) {
 		.pgsize_bitmap	= smmu->pgsize_bitmap,
@@ -2131,7 +1714,7 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain,
 	domain->geometry.aperture_end = (1UL << pgtbl_cfg.ias) - 1;
 	domain->geometry.force_aperture = true;
 
-	ret = finalise_stage_fn(smmu_domain, master, &pgtbl_cfg);
+	ret = arm_smmu_domain_finalise_s2(smmu_domain, master, &pgtbl_cfg);
 	if (ret < 0) {
 		free_io_pgtable_ops(pgtbl_ops);
 		return ret;
@@ -2264,8 +1847,6 @@ static int arm_smmu_enable_pasid(struct arm_smmu_master *master)
 		return ret;
 	}
 
-	master->ssid_bits = min_t(u8, ilog2(num_pasids),
-				  master->smmu->ssid_bits);
 	return 0;
 }
 
@@ -2281,7 +1862,6 @@ static void arm_smmu_disable_pasid(struct arm_smmu_master *master)
 	if (!pdev->pasid_enabled)
 		return;
 
-	master->ssid_bits = 0;
 	pci_disable_pasid(pdev);
 }
 
@@ -2337,13 +1917,6 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 			dev_name(smmu->dev));
 		ret = -ENXIO;
 		goto out_unlock;
-	} else if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1 &&
-		   master->ssid_bits != smmu_domain->s1_cfg.s1cdmax) {
-		dev_err(dev,
-			"cannot attach to incompatible domain (%u SSID bits != %u)\n",
-			smmu_domain->s1_cfg.s1cdmax, master->ssid_bits);
-		ret = -EINVAL;
-		goto out_unlock;
 	}
 
 	master->domain = smmu_domain;
@@ -2490,8 +2063,6 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
 		}
 	}
 
-	master->ssid_bits = min(smmu->ssid_bits, fwspec->num_pasid_bits);
-
 	/*
 	 * Note that PASID must be enabled before, and disabled after ATS:
 	 * PCI Express Base 4.0r1.0 - 10.5.1.3 ATS Control Register
@@ -2502,10 +2073,6 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
 	 */
 	arm_smmu_enable_pasid(master);
 
-	if (!(smmu->features & ARM_SMMU_FEAT_2_LVL_CDTAB))
-		master->ssid_bits = min_t(u8, master->ssid_bits,
-					  CTXDESC_LINEAR_CDMAX);
-
 	return &smmu->iommu;
 
 err_free_master:
@@ -3259,13 +2826,10 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 		smmu->features |= ARM_SMMU_FEAT_STALLS;
 	}
 
-	if (reg & IDR0_S1P)
-		smmu->features |= ARM_SMMU_FEAT_TRANS_S1;
-
 	if (reg & IDR0_S2P)
 		smmu->features |= ARM_SMMU_FEAT_TRANS_S2;
 
-	if (!(reg & (IDR0_S1P | IDR0_S2P))) {
+	if (!(reg & IDR0_S2P)) {
 		dev_err(smmu->dev, "no translation support!\n");
 		return -ENXIO;
 	}
@@ -3283,7 +2847,6 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 	}
 
 	/* ASID/VMID sizes */
-	smmu->asid_bits = reg & IDR0_ASID16 ? 16 : 8;
 	smmu->vmid_bits = reg & IDR0_VMID16 ? 16 : 8;
 
 	/* IDR1 */
@@ -3308,7 +2871,6 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 					     FIELD_GET(IDR1_PRIQS, reg));
 
 	/* SID/SSID sizes */
-	smmu->ssid_bits = FIELD_GET(IDR1_SSIDSIZE, reg);
 	smmu->sid_bits = FIELD_GET(IDR1_SIDSIZE, reg);
 
 	/*
-- 
2.17.1



^ permalink raw reply related	[flat|nested] 24+ messages in thread

* [PATCH v5 05/10] xen/arm: smmuv3: Remove Linux specific code that is not usable in XEN
  2021-01-20 14:52 [PATCH v5 00/10] xen/arm: Add support for SMMUv3 driver Rahul Singh
                   ` (3 preceding siblings ...)
  2021-01-20 14:52 ` [PATCH v5 04/10] xen/arm: smmuv3: Remove support for Stage-1 translation on SMMUv3 Rahul Singh
@ 2021-01-20 14:52 ` Rahul Singh
  2021-01-20 14:52 ` [PATCH v5 06/10] xen/device-tree: Add dt_property_match_string helper Rahul Singh
                   ` (4 subsequent siblings)
  9 siblings, 0 replies; 24+ messages in thread
From: Rahul Singh @ 2021-01-20 14:52 UTC (permalink / raw)
  To: xen-devel
  Cc: bertrand.marquis, rahul.singh, Stefano Stabellini, Julien Grall,
	Volodymyr Babchuk

Remove code that is related to below functionality :
 1. struct io_pgtable_ops
 2. struct io_pgtable_cfg
 3. struct iommu_flush_ops,
 4. struct iommu_ops
 5. module_param_named, MODULE_PARM_DESC, module_platform_driver,
    MODULE_*
 6. IOMMU domain-types
 7. arm_smmu_set_bus_ops
 8. iommu_device_sysfs_add, iommu_device_register,
    iommu_device_set_fwnode

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
---
Changes since v2:
- Commit message is updated to add more detail what is removed in this
  patch.
- remove instances of io_pgtable_cfg.
- Added back ARM_SMMU_FEAT_COHERENCY feature.
Changes since v3: No changes
Changes since v4: No changes
---
---
 xen/drivers/passthrough/arm/smmu-v3.c | 475 ++------------------------
 1 file changed, 21 insertions(+), 454 deletions(-)

diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
index 869f38b753..5ce14850b4 100644
--- a/xen/drivers/passthrough/arm/smmu-v3.c
+++ b/xen/drivers/passthrough/arm/smmu-v3.c
@@ -394,13 +394,7 @@
 #define ARM_SMMU_CMDQ_SYNC_TIMEOUT_US	1000000 /* 1s! */
 #define ARM_SMMU_CMDQ_SYNC_SPIN_COUNT	10
 
-#define MSI_IOVA_BASE			0x8000000
-#define MSI_IOVA_LENGTH			0x100000
-
 static bool disable_bypass = 1;
-module_param_named(disable_bypass, disable_bypass, bool, S_IRUGO);
-MODULE_PARM_DESC(disable_bypass,
-	"Disable bypass streams such that incoming transactions from devices that are not attached to an iommu domain will report an abort back to the device and will not be allowed to pass through the SMMU.");
 
 enum pri_resp {
 	PRI_RESP_DENY = 0,
@@ -552,6 +546,19 @@ struct arm_smmu_strtab_cfg {
 	u32				strtab_base_cfg;
 };
 
+struct arm_lpae_s2_cfg {
+	u64			vttbr;
+	struct {
+		u32			ps:3;
+		u32			tg:2;
+		u32			sh:2;
+		u32			orgn:2;
+		u32			irgn:2;
+		u32			sl:2;
+		u32			tsz:6;
+	} vtcr;
+};
+
 /* An SMMUv3 instance */
 struct arm_smmu_device {
 	struct device			*dev;
@@ -633,7 +640,6 @@ struct arm_smmu_domain {
 	struct arm_smmu_device		*smmu;
 	struct mutex			init_mutex; /* Protects smmu pointer */
 
-	struct io_pgtable_ops		*pgtbl_ops;
 	bool				non_strict;
 	atomic_t			nr_ats_masters;
 
@@ -1491,7 +1497,6 @@ static int arm_smmu_atc_inv_domain(struct arm_smmu_domain *smmu_domain,
 	return ret ? -ETIMEDOUT : 0;
 }
 
-/* IO_PGTABLE API */
 static void arm_smmu_tlb_inv_context(void *cookie)
 {
 	struct arm_smmu_domain *smmu_domain = cookie;
@@ -1512,86 +1517,10 @@ static void arm_smmu_tlb_inv_context(void *cookie)
 	arm_smmu_cmdq_issue_sync(smmu);
 }
 
-static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
-					  size_t granule, bool leaf, void *cookie)
-{
-	struct arm_smmu_domain *smmu_domain = cookie;
-	struct arm_smmu_device *smmu = smmu_domain->smmu;
-	struct arm_smmu_cmdq_ent cmd = {
-		.tlbi = {
-			.leaf	= leaf,
-			.addr	= iova,
-		},
-	};
-
-	if (!size)
-		return;
-
-	cmd.opcode	= CMDQ_OP_TLBI_S2_IPA;
-	cmd.tlbi.vmid	= smmu_domain->s2_cfg.vmid;
-
-	do {
-		arm_smmu_cmdq_issue_cmd(smmu, &cmd);
-		cmd.tlbi.addr += granule;
-	} while (size -= granule);
-}
-
-static void arm_smmu_tlb_inv_page_nosync(struct iommu_iotlb_gather *gather,
-					 unsigned long iova, size_t granule,
-					 void *cookie)
-{
-	arm_smmu_tlb_inv_range_nosync(iova, granule, granule, true, cookie);
-}
-
-static void arm_smmu_tlb_inv_walk(unsigned long iova, size_t size,
-				  size_t granule, void *cookie)
-{
-	struct arm_smmu_domain *smmu_domain = cookie;
-	struct arm_smmu_device *smmu = smmu_domain->smmu;
-
-	arm_smmu_tlb_inv_range_nosync(iova, size, granule, false, cookie);
-	arm_smmu_cmdq_issue_sync(smmu);
-}
-
-static void arm_smmu_tlb_inv_leaf(unsigned long iova, size_t size,
-				  size_t granule, void *cookie)
-{
-	struct arm_smmu_domain *smmu_domain = cookie;
-	struct arm_smmu_device *smmu = smmu_domain->smmu;
-
-	arm_smmu_tlb_inv_range_nosync(iova, size, granule, true, cookie);
-	arm_smmu_cmdq_issue_sync(smmu);
-}
-
-static const struct iommu_flush_ops arm_smmu_flush_ops = {
-	.tlb_flush_all	= arm_smmu_tlb_inv_context,
-	.tlb_flush_walk = arm_smmu_tlb_inv_walk,
-	.tlb_flush_leaf = arm_smmu_tlb_inv_leaf,
-	.tlb_add_page	= arm_smmu_tlb_inv_page_nosync,
-};
-
-/* IOMMU API */
-static bool arm_smmu_capable(enum iommu_cap cap)
-{
-	switch (cap) {
-	case IOMMU_CAP_CACHE_COHERENCY:
-		return true;
-	case IOMMU_CAP_NOEXEC:
-		return true;
-	default:
-		return false;
-	}
-}
-
-static struct iommu_domain *arm_smmu_domain_alloc(unsigned type)
+static struct iommu_domain *arm_smmu_domain_alloc(void)
 {
 	struct arm_smmu_domain *smmu_domain;
 
-	if (type != IOMMU_DOMAIN_UNMANAGED &&
-	    type != IOMMU_DOMAIN_DMA &&
-	    type != IOMMU_DOMAIN_IDENTITY)
-		return NULL;
-
 	/*
 	 * Allocate the domain and initialise some of its data structures.
 	 * We can't really do anything meaningful until we've added a
@@ -1601,12 +1530,6 @@ static struct iommu_domain *arm_smmu_domain_alloc(unsigned type)
 	if (!smmu_domain)
 		return NULL;
 
-	if (type == IOMMU_DOMAIN_DMA &&
-	    iommu_get_dma_cookie(&smmu_domain->domain)) {
-		kfree(smmu_domain);
-		return NULL;
-	}
-
 	mutex_init(&smmu_domain->init_mutex);
 	INIT_LIST_HEAD(&smmu_domain->devices);
 	spin_lock_init(&smmu_domain->devices_lock);
@@ -1638,9 +1561,6 @@ static void arm_smmu_domain_free(struct iommu_domain *domain)
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
 	struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
 
-	iommu_put_dma_cookie(domain);
-	free_io_pgtable_ops(smmu_domain->pgtbl_ops);
-
 	if (cfg->vmid)
 		arm_smmu_bitmap_free(smmu->vmid_map, cfg->vmid);
 
@@ -1649,21 +1569,20 @@ static void arm_smmu_domain_free(struct iommu_domain *domain)
 
 
 static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
-				       struct arm_smmu_master *master,
-				       struct io_pgtable_cfg *pgtbl_cfg)
+				       struct arm_smmu_master *master)
 {
 	int vmid;
+	struct arm_lpae_s2_cfg arm_lpae_s2_cfg;
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
 	struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
-	typeof(&pgtbl_cfg->arm_lpae_s2_cfg.vtcr) vtcr;
+	typeof(&arm_lpae_s2_cfg.vtcr) vtcr = &arm_lpae_s2_cfg.vtcr;
 
 	vmid = arm_smmu_bitmap_alloc(smmu->vmid_map, smmu->vmid_bits);
 	if (vmid < 0)
 		return vmid;
 
-	vtcr = &pgtbl_cfg->arm_lpae_s2_cfg.vtcr;
 	cfg->vmid	= (u16)vmid;
-	cfg->vttbr	= pgtbl_cfg->arm_lpae_s2_cfg.vttbr;
+	cfg->vttbr	= arm_lpae_s2_cfg.vttbr;
 	cfg->vtcr	= FIELD_PREP(STRTAB_STE_2_VTCR_S2T0SZ, vtcr->tsz) |
 			  FIELD_PREP(STRTAB_STE_2_VTCR_S2SL0, vtcr->sl) |
 			  FIELD_PREP(STRTAB_STE_2_VTCR_S2IR0, vtcr->irgn) |
@@ -1678,49 +1597,15 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain,
 				    struct arm_smmu_master *master)
 {
 	int ret;
-	unsigned long ias, oas;
-	enum io_pgtable_fmt fmt;
-	struct io_pgtable_cfg pgtbl_cfg;
-	struct io_pgtable_ops *pgtbl_ops;
 	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
-	struct arm_smmu_device *smmu = smmu_domain->smmu;
-
-	if (domain->type == IOMMU_DOMAIN_IDENTITY) {
-		smmu_domain->stage = ARM_SMMU_DOMAIN_BYPASS;
-		return 0;
-	}
 
 	/* Restrict the stage to what we can actually support */
 	smmu_domain->stage = ARM_SMMU_DOMAIN_S2;
 
-
-	pgtbl_cfg = (struct io_pgtable_cfg) {
-		.pgsize_bitmap	= smmu->pgsize_bitmap,
-		.ias		= ias,
-		.oas		= oas,
-		.coherent_walk	= smmu->features & ARM_SMMU_FEAT_COHERENCY,
-		.tlb		= &arm_smmu_flush_ops,
-		.iommu_dev	= smmu->dev,
-	};
-
-	if (smmu_domain->non_strict)
-		pgtbl_cfg.quirks |= IO_PGTABLE_QUIRK_NON_STRICT;
-
-	pgtbl_ops = alloc_io_pgtable_ops(fmt, &pgtbl_cfg, smmu_domain);
-	if (!pgtbl_ops)
-		return -ENOMEM;
-
-	domain->pgsize_bitmap = pgtbl_cfg.pgsize_bitmap;
-	domain->geometry.aperture_end = (1UL << pgtbl_cfg.ias) - 1;
-	domain->geometry.force_aperture = true;
-
-	ret = arm_smmu_domain_finalise_s2(smmu_domain, master, &pgtbl_cfg);
-	if (ret < 0) {
-		free_io_pgtable_ops(pgtbl_ops);
+	ret = arm_smmu_domain_finalise_s2(smmu_domain, master);
+	if (ret < 0)
 		return ret;
-	}
 
-	smmu_domain->pgtbl_ops = pgtbl_ops;
 	return 0;
 }
 
@@ -1937,76 +1822,6 @@ out_unlock:
 	return ret;
 }
 
-static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova,
-			phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
-{
-	struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops;
-
-	if (!ops)
-		return -ENODEV;
-
-	return ops->map(ops, iova, paddr, size, prot);
-}
-
-static size_t arm_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
-			     size_t size, struct iommu_iotlb_gather *gather)
-{
-	int ret;
-	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
-	struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops;
-
-	if (!ops)
-		return 0;
-
-	ret = ops->unmap(ops, iova, size, gather);
-	if (ret && arm_smmu_atc_inv_domain(smmu_domain, 0, iova, size))
-		return 0;
-
-	return ret;
-}
-
-static void arm_smmu_flush_iotlb_all(struct iommu_domain *domain)
-{
-	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
-
-	if (smmu_domain->smmu)
-		arm_smmu_tlb_inv_context(smmu_domain);
-}
-
-static void arm_smmu_iotlb_sync(struct iommu_domain *domain,
-				struct iommu_iotlb_gather *gather)
-{
-	struct arm_smmu_device *smmu = to_smmu_domain(domain)->smmu;
-
-	if (smmu)
-		arm_smmu_cmdq_issue_sync(smmu);
-}
-
-static phys_addr_t
-arm_smmu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
-{
-	struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops;
-
-	if (domain->type == IOMMU_DOMAIN_IDENTITY)
-		return iova;
-
-	if (!ops)
-		return 0;
-
-	return ops->iova_to_phys(ops, iova);
-}
-
-static struct platform_driver arm_smmu_driver;
-
-static
-struct arm_smmu_device *arm_smmu_get_by_fwnode(struct fwnode_handle *fwnode)
-{
-	struct device *dev = driver_find_device_by_fwnode(&arm_smmu_driver.driver,
-							  fwnode);
-	put_device(dev);
-	return dev ? dev_get_drvdata(dev) : NULL;
-}
-
 static bool arm_smmu_sid_in_range(struct arm_smmu_device *smmu, u32 sid)
 {
 	unsigned long limit = smmu->strtab_cfg.num_l1_ents;
@@ -2017,8 +1832,6 @@ static bool arm_smmu_sid_in_range(struct arm_smmu_device *smmu, u32 sid)
 	return sid < limit;
 }
 
-static struct iommu_ops arm_smmu_ops;
-
 static struct iommu_device *arm_smmu_probe_device(struct device *dev)
 {
 	int i, ret;
@@ -2026,16 +1839,12 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
 	struct arm_smmu_master *master;
 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 
-	if (!fwspec || fwspec->ops != &arm_smmu_ops)
+	if (!fwspec)
 		return ERR_PTR(-ENODEV);
 
 	if (WARN_ON_ONCE(dev_iommu_priv_get(dev)))
 		return ERR_PTR(-EBUSY);
 
-	smmu = arm_smmu_get_by_fwnode(fwspec->iommu_fwnode);
-	if (!smmu)
-		return ERR_PTR(-ENODEV);
-
 	master = kzalloc(sizeof(*master), GFP_KERNEL);
 	if (!master)
 		return ERR_PTR(-ENOMEM);
@@ -2081,153 +1890,11 @@ err_free_master:
 	return ERR_PTR(ret);
 }
 
-static void arm_smmu_release_device(struct device *dev)
-{
-	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
-	struct arm_smmu_master *master;
-
-	if (!fwspec || fwspec->ops != &arm_smmu_ops)
-		return;
-
-	master = dev_iommu_priv_get(dev);
-	arm_smmu_detach_dev(master);
-	arm_smmu_disable_pasid(master);
-	kfree(master);
-	iommu_fwspec_free(dev);
-}
-
-static struct iommu_group *arm_smmu_device_group(struct device *dev)
-{
-	struct iommu_group *group;
-
-	/*
-	 * We don't support devices sharing stream IDs other than PCI RID
-	 * aliases, since the necessary ID-to-device lookup becomes rather
-	 * impractical given a potential sparse 32-bit stream ID space.
-	 */
-	if (dev_is_pci(dev))
-		group = pci_device_group(dev);
-	else
-		group = generic_device_group(dev);
-
-	return group;
-}
-
-static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
-				    enum iommu_attr attr, void *data)
-{
-	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
-
-	switch (domain->type) {
-	case IOMMU_DOMAIN_UNMANAGED:
-		switch (attr) {
-		case DOMAIN_ATTR_NESTING:
-			*(int *)data = (smmu_domain->stage == ARM_SMMU_DOMAIN_NESTED);
-			return 0;
-		default:
-			return -ENODEV;
-		}
-		break;
-	case IOMMU_DOMAIN_DMA:
-		switch (attr) {
-		case DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE:
-			*(int *)data = smmu_domain->non_strict;
-			return 0;
-		default:
-			return -ENODEV;
-		}
-		break;
-	default:
-		return -EINVAL;
-	}
-}
-
-static int arm_smmu_domain_set_attr(struct iommu_domain *domain,
-				    enum iommu_attr attr, void *data)
-{
-	int ret = 0;
-	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
-
-	mutex_lock(&smmu_domain->init_mutex);
-
-	switch (domain->type) {
-	case IOMMU_DOMAIN_UNMANAGED:
-		switch (attr) {
-		case DOMAIN_ATTR_NESTING:
-			if (smmu_domain->smmu) {
-				ret = -EPERM;
-				goto out_unlock;
-			}
-
-			if (*(int *)data)
-				smmu_domain->stage = ARM_SMMU_DOMAIN_NESTED;
-			else
-				smmu_domain->stage = ARM_SMMU_DOMAIN_S1;
-			break;
-		default:
-			ret = -ENODEV;
-		}
-		break;
-	case IOMMU_DOMAIN_DMA:
-		switch(attr) {
-		case DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE:
-			smmu_domain->non_strict = *(int *)data;
-			break;
-		default:
-			ret = -ENODEV;
-		}
-		break;
-	default:
-		ret = -EINVAL;
-	}
-
-out_unlock:
-	mutex_unlock(&smmu_domain->init_mutex);
-	return ret;
-}
-
 static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args)
 {
 	return iommu_fwspec_add_ids(dev, args->args, 1);
 }
 
-static void arm_smmu_get_resv_regions(struct device *dev,
-				      struct list_head *head)
-{
-	struct iommu_resv_region *region;
-	int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO;
-
-	region = iommu_alloc_resv_region(MSI_IOVA_BASE, MSI_IOVA_LENGTH,
-					 prot, IOMMU_RESV_SW_MSI);
-	if (!region)
-		return;
-
-	list_add_tail(&region->list, head);
-
-	iommu_dma_get_resv_regions(dev, head);
-}
-
-static struct iommu_ops arm_smmu_ops = {
-	.capable		= arm_smmu_capable,
-	.domain_alloc		= arm_smmu_domain_alloc,
-	.domain_free		= arm_smmu_domain_free,
-	.attach_dev		= arm_smmu_attach_dev,
-	.map			= arm_smmu_map,
-	.unmap			= arm_smmu_unmap,
-	.flush_iotlb_all	= arm_smmu_flush_iotlb_all,
-	.iotlb_sync		= arm_smmu_iotlb_sync,
-	.iova_to_phys		= arm_smmu_iova_to_phys,
-	.probe_device		= arm_smmu_probe_device,
-	.release_device		= arm_smmu_release_device,
-	.device_group		= arm_smmu_device_group,
-	.domain_get_attr	= arm_smmu_domain_get_attr,
-	.domain_set_attr	= arm_smmu_domain_set_attr,
-	.of_xlate		= arm_smmu_of_xlate,
-	.get_resv_regions	= arm_smmu_get_resv_regions,
-	.put_resv_regions	= generic_iommu_put_resv_regions,
-	.pgsize_bitmap		= -1UL, /* Restricted during device attach */
-};
-
 /* Probing and initialisation functions */
 static int arm_smmu_init_one_queue(struct arm_smmu_device *smmu,
 				   struct arm_smmu_queue *q,
@@ -2927,16 +2594,6 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 		smmu->oas = 48;
 	}
 
-	if (arm_smmu_ops.pgsize_bitmap == -1UL)
-		arm_smmu_ops.pgsize_bitmap = smmu->pgsize_bitmap;
-	else
-		arm_smmu_ops.pgsize_bitmap |= smmu->pgsize_bitmap;
-
-	/* Set the DMA mask for our table walker */
-	if (dma_set_mask_and_coherent(smmu->dev, DMA_BIT_MASK(smmu->oas)))
-		dev_warn(smmu->dev,
-			 "failed to set DMA mask for table walker\n");
-
 	smmu->ias = max(smmu->ias, smmu->oas);
 
 	dev_info(smmu->dev, "ias %lu-bit, oas %lu-bit (features 0x%08x)\n",
@@ -3016,43 +2673,6 @@ static unsigned long arm_smmu_resource_size(struct arm_smmu_device *smmu)
 		return SZ_128K;
 }
 
-static int arm_smmu_set_bus_ops(struct iommu_ops *ops)
-{
-	int err;
-
-#ifdef CONFIG_PCI
-	if (pci_bus_type.iommu_ops != ops) {
-		err = bus_set_iommu(&pci_bus_type, ops);
-		if (err)
-			return err;
-	}
-#endif
-#ifdef CONFIG_ARM_AMBA
-	if (amba_bustype.iommu_ops != ops) {
-		err = bus_set_iommu(&amba_bustype, ops);
-		if (err)
-			goto err_reset_pci_ops;
-	}
-#endif
-	if (platform_bus_type.iommu_ops != ops) {
-		err = bus_set_iommu(&platform_bus_type, ops);
-		if (err)
-			goto err_reset_amba_ops;
-	}
-
-	return 0;
-
-err_reset_amba_ops:
-#ifdef CONFIG_ARM_AMBA
-	bus_set_iommu(&amba_bustype, NULL);
-#endif
-err_reset_pci_ops: __maybe_unused;
-#ifdef CONFIG_PCI
-	bus_set_iommu(&pci_bus_type, NULL);
-#endif
-	return err;
-}
-
 static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
 				      resource_size_t size)
 {
@@ -3145,68 +2765,15 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	/* Record our private device structure */
-	platform_set_drvdata(pdev, smmu);
-
 	/* Reset the device */
 	ret = arm_smmu_device_reset(smmu, bypass);
 	if (ret)
 		return ret;
 
-	/* And we're up. Go go go! */
-	ret = iommu_device_sysfs_add(&smmu->iommu, dev, NULL,
-				     "smmu3.%pa", &ioaddr);
-	if (ret)
-		return ret;
-
-	iommu_device_set_ops(&smmu->iommu, &arm_smmu_ops);
-	iommu_device_set_fwnode(&smmu->iommu, dev->fwnode);
-
-	ret = iommu_device_register(&smmu->iommu);
-	if (ret) {
-		dev_err(dev, "Failed to register iommu\n");
-		return ret;
-	}
-
-	return arm_smmu_set_bus_ops(&arm_smmu_ops);
-}
-
-static int arm_smmu_device_remove(struct platform_device *pdev)
-{
-	struct arm_smmu_device *smmu = platform_get_drvdata(pdev);
-
-	arm_smmu_set_bus_ops(NULL);
-	iommu_device_unregister(&smmu->iommu);
-	iommu_device_sysfs_remove(&smmu->iommu);
-	arm_smmu_device_disable(smmu);
-
 	return 0;
 }
 
-static void arm_smmu_device_shutdown(struct platform_device *pdev)
-{
-	arm_smmu_device_remove(pdev);
-}
-
 static const struct of_device_id arm_smmu_of_match[] = {
 	{ .compatible = "arm,smmu-v3", },
 	{ },
 };
-MODULE_DEVICE_TABLE(of, arm_smmu_of_match);
-
-static struct platform_driver arm_smmu_driver = {
-	.driver	= {
-		.name			= "arm-smmu-v3",
-		.of_match_table		= arm_smmu_of_match,
-		.suppress_bind_attrs	= true,
-	},
-	.probe	= arm_smmu_device_probe,
-	.remove	= arm_smmu_device_remove,
-	.shutdown = arm_smmu_device_shutdown,
-};
-module_platform_driver(arm_smmu_driver);
-
-MODULE_DESCRIPTION("IOMMU API for ARM architected SMMUv3 implementations");
-MODULE_AUTHOR("Will Deacon <will@kernel.org>");
-MODULE_ALIAS("platform:arm-smmu-v3");
-MODULE_LICENSE("GPL v2");
-- 
2.17.1



^ permalink raw reply related	[flat|nested] 24+ messages in thread

* [PATCH v5 06/10] xen/device-tree: Add dt_property_match_string helper
  2021-01-20 14:52 [PATCH v5 00/10] xen/arm: Add support for SMMUv3 driver Rahul Singh
                   ` (4 preceding siblings ...)
  2021-01-20 14:52 ` [PATCH v5 05/10] xen/arm: smmuv3: Remove Linux specific code that is not usable in XEN Rahul Singh
@ 2021-01-20 14:52 ` Rahul Singh
  2021-01-20 14:52 ` [PATCH v5 07/10] xen/compiler: import 'fallthrough' keyword from linux Rahul Singh
                   ` (3 subsequent siblings)
  9 siblings, 0 replies; 24+ messages in thread
From: Rahul Singh @ 2021-01-20 14:52 UTC (permalink / raw)
  To: xen-devel; +Cc: bertrand.marquis, rahul.singh, Stefano Stabellini, Julien Grall

Import the Linux helper of_property_match_string. This function searches
a string list property and returns the index of a specific string value.

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
---
Changes since v2:
 - This patch is introduce in this verison.
Changes since v3: No changes
Changes since v4: No changes
---
---
 xen/common/device_tree.c      | 27 +++++++++++++++++++++++++++
 xen/include/xen/device_tree.h | 12 ++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/xen/common/device_tree.c b/xen/common/device_tree.c
index e107c6f89f..18825e333e 100644
--- a/xen/common/device_tree.c
+++ b/xen/common/device_tree.c
@@ -208,6 +208,33 @@ int dt_property_read_string(const struct dt_device_node *np,
     return 0;
 }
 
+int dt_property_match_string(const struct dt_device_node *np,
+                             const char *propname, const char *string)
+{
+    const struct dt_property *dtprop = dt_find_property(np, propname, NULL);
+    size_t l;
+    int i;
+    const char *p, *end;
+
+    if ( !dtprop )
+        return -EINVAL;
+    if ( !dtprop->value )
+        return -ENODATA;
+
+    p = dtprop->value;
+    end = p + dtprop->length;
+
+    for ( i = 0; p < end; i++, p += l )
+    {
+        l = strnlen(p, end - p) + 1;
+        if ( p + l > end )
+            return -EILSEQ;
+        if ( strcmp(string, p) == 0 )
+            return i; /* Found it; return index */
+    }
+    return -ENODATA;
+}
+
 bool_t dt_device_is_compatible(const struct dt_device_node *device,
                                const char *compat)
 {
diff --git a/xen/include/xen/device_tree.h b/xen/include/xen/device_tree.h
index f2ad22b79c..b02696be94 100644
--- a/xen/include/xen/device_tree.h
+++ b/xen/include/xen/device_tree.h
@@ -400,6 +400,18 @@ static inline bool_t dt_property_read_bool(const struct dt_device_node *np,
 int dt_property_read_string(const struct dt_device_node *np,
                             const char *propname, const char **out_string);
 
+/**
+ * dt_property_match_string() - Find string in a list and return index
+ * @np: pointer to node containing string list property
+ * @propname: string list property name
+ * @string: pointer to string to search for in string list
+ *
+ * This function searches a string list property and returns the index
+ * of a specific string value.
+ */
+int dt_property_match_string(const struct dt_device_node *np,
+                             const char *propname, const char *string);
+
 /**
  * Checks if the given "compat" string matches one of the strings in
  * the device's "compatible" property
-- 
2.17.1



^ permalink raw reply related	[flat|nested] 24+ messages in thread

* [PATCH v5 07/10] xen/compiler: import 'fallthrough' keyword from linux
  2021-01-20 14:52 [PATCH v5 00/10] xen/arm: Add support for SMMUv3 driver Rahul Singh
                   ` (5 preceding siblings ...)
  2021-01-20 14:52 ` [PATCH v5 06/10] xen/device-tree: Add dt_property_match_string helper Rahul Singh
@ 2021-01-20 14:52 ` Rahul Singh
  2021-01-20 14:52 ` [PATCH v5 08/10] xen/arm: smmuv3: Use fallthrough pseudo-keyword Rahul Singh
                   ` (2 subsequent siblings)
  9 siblings, 0 replies; 24+ messages in thread
From: Rahul Singh @ 2021-01-20 14:52 UTC (permalink / raw)
  To: xen-devel
  Cc: bertrand.marquis, rahul.singh, Andrew Cooper, George Dunlap,
	Ian Jackson, Jan Beulich, Julien Grall, Stefano Stabellini,
	Wei Liu

-Wimplicit-fallthrough warns when a switch case falls through. Warning
can be suppress by either adding a /* fallthrough */ comment, or by
using a null statement: __attribute__ ((fallthrough))

Define the pseudo keyword 'fallthrough' for the ability to convert the
various case block /* fallthrough */ style comments to null statement
"__attribute__((__fallthrough__))"

In C mode, GCC supports the __fallthrough__ attribute since 7.1,
the same time the warning and the comment parsing were introduced.

fallthrough devolves to an empty "do {} while (0)" if the compiler
version (any version less than gcc 7) does not support the attribute.

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
---
Changes since v3:
 - This patch is introduce in this version.
Changes since v4: No changes
---
---
 xen/include/xen/compiler.h | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/xen/include/xen/compiler.h b/xen/include/xen/compiler.h
index e643e69128..0ec0b4698e 100644
--- a/xen/include/xen/compiler.h
+++ b/xen/include/xen/compiler.h
@@ -33,6 +33,22 @@
 #define unreachable() __builtin_unreachable()
 #endif
 
+/*
+ * Add the pseudo keyword 'fallthrough' so case statement blocks
+ * must end with any of these keywords:
+ *   break;
+ *   fallthrough;
+ *   goto <label>;
+ *   return [expression];
+ *
+ *  gcc: https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html#Statement-Attributes
+ */
+#if (!defined(__clang__) && (__GNUC__ >= 7))
+# define fallthrough        __attribute__((__fallthrough__))
+#else
+# define fallthrough        do {} while (0)  /* fallthrough */
+#endif
+
 #ifdef __clang__
 /* Clang can replace some vars with new automatic ones that go in .data;
  * mark all explicit-segment vars 'used' to prevent that. */
-- 
2.17.1



^ permalink raw reply related	[flat|nested] 24+ messages in thread

* [PATCH v5 08/10] xen/arm: smmuv3: Use fallthrough pseudo-keyword
  2021-01-20 14:52 [PATCH v5 00/10] xen/arm: Add support for SMMUv3 driver Rahul Singh
                   ` (6 preceding siblings ...)
  2021-01-20 14:52 ` [PATCH v5 07/10] xen/compiler: import 'fallthrough' keyword from linux Rahul Singh
@ 2021-01-20 14:52 ` Rahul Singh
  2021-01-20 15:36   ` Bertrand Marquis
  2021-01-20 19:56   ` Stefano Stabellini
  2021-01-20 14:52 ` [PATCH v5 09/10] xen/arm: smmuv3: Replace linux functions with xen functions Rahul Singh
  2021-01-20 14:52 ` [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver Rahul Singh
  9 siblings, 2 replies; 24+ messages in thread
From: Rahul Singh @ 2021-01-20 14:52 UTC (permalink / raw)
  To: xen-devel
  Cc: bertrand.marquis, rahul.singh, Stefano Stabellini, Julien Grall,
	Volodymyr Babchuk

Backport commit df561f6688fef775baa341a0f5d960becd248b11
"treewide: Use fallthrough pseudo-keyword" from Linux kernel.

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
---
Changes since v3:
 - This patch is introduce in this version.
Changes since v4:
 - Add more information about the merged patch in commit message.
---
---
 xen/drivers/passthrough/arm/smmu-v3.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
index 5ce14850b4..f5f8b4c981 100644
--- a/xen/drivers/passthrough/arm/smmu-v3.c
+++ b/xen/drivers/passthrough/arm/smmu-v3.c
@@ -932,7 +932,6 @@ static void arm_smmu_cmdq_skip_err(struct arm_smmu_device *smmu)
 		 */
 		return;
 	case CMDQ_ERR_CERROR_ILL_IDX:
-		/* Fallthrough */
 	default:
 		break;
 	}
@@ -2488,7 +2487,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 	switch (FIELD_GET(IDR0_STALL_MODEL, reg)) {
 	case IDR0_STALL_MODEL_FORCE:
 		smmu->features |= ARM_SMMU_FEAT_STALL_FORCE;
-		/* Fallthrough */
+		fallthrough;
 	case IDR0_STALL_MODEL_STALL:
 		smmu->features |= ARM_SMMU_FEAT_STALLS;
 	}
@@ -2505,7 +2504,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 	switch (FIELD_GET(IDR0_TTF, reg)) {
 	case IDR0_TTF_AARCH32_64:
 		smmu->ias = 40;
-		/* Fallthrough */
+		fallthrough;
 	case IDR0_TTF_AARCH64:
 		break;
 	default:
@@ -2589,7 +2588,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 	default:
 		dev_info(smmu->dev,
 			"unknown output address size. Truncating to 48-bit\n");
-		/* Fallthrough */
+		fallthrough;
 	case IDR5_OAS_48_BIT:
 		smmu->oas = 48;
 	}
-- 
2.17.1



^ permalink raw reply related	[flat|nested] 24+ messages in thread

* [PATCH v5 09/10] xen/arm: smmuv3: Replace linux functions with xen functions.
  2021-01-20 14:52 [PATCH v5 00/10] xen/arm: Add support for SMMUv3 driver Rahul Singh
                   ` (7 preceding siblings ...)
  2021-01-20 14:52 ` [PATCH v5 08/10] xen/arm: smmuv3: Use fallthrough pseudo-keyword Rahul Singh
@ 2021-01-20 14:52 ` Rahul Singh
  2021-01-20 14:52 ` [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver Rahul Singh
  9 siblings, 0 replies; 24+ messages in thread
From: Rahul Singh @ 2021-01-20 14:52 UTC (permalink / raw)
  To: xen-devel
  Cc: bertrand.marquis, rahul.singh, Stefano Stabellini, Julien Grall,
	Volodymyr Babchuk

Replace all Linux device tree handling function with the XEN
functions.

Replace all Linux ktime function with the XEN time functions.

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
---
Changes since v2:
 - This patch is introduce in this version.
Changes since v3:
 - Move this patch one patch earlier so that there is no need to remove
   the code.
Changes since v4: No changes
---
---
 xen/drivers/passthrough/arm/smmu-v3.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
index f5f8b4c981..2dfadc6a65 100644
--- a/xen/drivers/passthrough/arm/smmu-v3.c
+++ b/xen/drivers/passthrough/arm/smmu-v3.c
@@ -682,7 +682,7 @@ static void parse_driver_options(struct arm_smmu_device *smmu)
 	int i = 0;
 
 	do {
-		if (of_property_read_bool(smmu->dev->of_node,
+		if (dt_property_read_bool(smmu->dev->of_node,
 						arm_smmu_options[i].prop)) {
 			smmu->options |= arm_smmu_options[i].opt;
 			dev_notice(smmu->dev, "option %s\n",
@@ -754,17 +754,17 @@ static void queue_inc_prod(struct arm_smmu_ll_queue *q)
  */
 static int queue_poll_cons(struct arm_smmu_queue *q, bool sync, bool wfe)
 {
-	ktime_t timeout;
+	s_time_t timeout;
 	unsigned int delay = 1, spin_cnt = 0;
 
 	/* Wait longer if it's a CMD_SYNC */
-	timeout = ktime_add_us(ktime_get(), sync ?
+	timeout = NOW() + MICROSECS(sync ?
 					    ARM_SMMU_CMDQ_SYNC_TIMEOUT_US :
 					    ARM_SMMU_POLL_TIMEOUT_US);
 
 	while (queue_sync_cons_in(q),
 	      (sync ? !queue_empty(&q->llq) : queue_full(&q->llq))) {
-		if (ktime_compare(ktime_get(), timeout) > 0)
+		if ((NOW() > timeout) > 0)
 			return -ETIMEDOUT;
 
 		if (wfe) {
@@ -990,13 +990,13 @@ static void arm_smmu_cmdq_issue_cmd(struct arm_smmu_device *smmu,
  */
 static int __arm_smmu_sync_poll_msi(struct arm_smmu_device *smmu, u32 sync_idx)
 {
-	ktime_t timeout;
+	s_time_t timeout;
 	u32 val;
 
-	timeout = ktime_add_us(ktime_get(), ARM_SMMU_CMDQ_SYNC_TIMEOUT_US);
+	timeout = NOW() + MICROSECS(ARM_SMMU_CMDQ_SYNC_TIMEOUT_US);
 	val = smp_cond_load_acquire(&smmu->sync_count,
 				    (int)(VAL - sync_idx) >= 0 ||
-				    !ktime_before(ktime_get(), timeout));
+				    !(NOW() < timeout));
 
 	return (int)(val - sync_idx) < 0 ? -ETIMEDOUT : 0;
 }
@@ -2649,7 +2649,7 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev,
 	u32 cells;
 	int ret = -EINVAL;
 
-	if (of_property_read_u32(dev->of_node, "#iommu-cells", &cells))
+	if (!dt_property_read_u32(dev->of_node, "#iommu-cells", &cells))
 		dev_err(dev, "missing #iommu-cells property\n");
 	else if (cells != 1)
 		dev_err(dev, "invalid #iommu-cells value (%d)\n", cells);
-- 
2.17.1



^ permalink raw reply related	[flat|nested] 24+ messages in thread

* [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver
  2021-01-20 14:52 [PATCH v5 00/10] xen/arm: Add support for SMMUv3 driver Rahul Singh
                   ` (8 preceding siblings ...)
  2021-01-20 14:52 ` [PATCH v5 09/10] xen/arm: smmuv3: Replace linux functions with xen functions Rahul Singh
@ 2021-01-20 14:52 ` Rahul Singh
  2021-01-20 15:35   ` Bertrand Marquis
                     ` (2 more replies)
  9 siblings, 3 replies; 24+ messages in thread
From: Rahul Singh @ 2021-01-20 14:52 UTC (permalink / raw)
  To: xen-devel
  Cc: bertrand.marquis, rahul.singh, Andrew Cooper, George Dunlap,
	Ian Jackson, Jan Beulich, Julien Grall, Stefano Stabellini,
	Wei Liu, Paul Durrant, Volodymyr Babchuk

Add support for ARM architected SMMUv3 implementation. It is based on
the Linux SMMUv3 driver.

Driver is currently supported as Tech Preview.

Major differences with regard to Linux driver are as follows:
2. Only Stage-2 translation is supported as compared to the Linux driver
   that supports both Stage-1 and Stage-2 translations.
3. Use P2M  page table instead of creating one as SMMUv3 has the
   capability to share the page tables with the CPU.
4. Tasklets are used in place of threaded IRQ's in Linux for event queue
   and priority queue IRQ handling.
5. Latest version of the Linux SMMUv3 code implements the commands queue
   access functions based on atomic operations implemented in Linux.
   Atomic functions used by the commands queue access functions are not
   implemented in XEN therefore we decided to port the earlier version
   of the code. Atomic operations are introduced to fix the bottleneck
   of the SMMU command queue insertion operation. A new algorithm for
   inserting commands into the queue is introduced, which is lock-free
   on the fast-path.
   Consequence of reverting the patch is that the command queue
   insertion will be slow for large systems as spinlock will be used to
   serializes accesses from all CPUs to the single queue supported by
   the hardware. Once the proper atomic operations will be available in
   XEN the driver can be updated.
6. Spin lock is used in place of mutex when attaching a device to the
   SMMU, as there is no blocking locks implementation available in XEN.
   This might introduce latency in XEN. Need to investigate before
   driver is out for tech preview.
7. PCI ATS functionality is not supported, as there is no support
   available in XEN to test the functionality. Code is not tested and
   compiled. Code is guarded by the flag CONFIG_PCI_ATS.
8. MSI interrupts are not supported as there is no support available in
   XEN to request MSI interrupts. Code is not tested and compiled. Code
   is guarded by the flag CONFIG_MSI.

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
---
Changes since v2:
- added return statement for readx_poll_timeout function.
- remove iommu_get_dma_cookie and iommu_put_dma_cookie.
- remove struct arm_smmu_xen_device as not required.
- move dt_property_match_string to device_tree.c file.
- replace arm_smmu_*_thread to arm_smmu_*_tasklet to avoid confusion.
- use ARM_SMMU_REG_SZ as size when map memory to XEN.
- remove bypass keyword to make sure when device-tree probe is failed we
  are reporting error and not continuing to configure SMMU in bypass
  mode.
- fixed minor comments.
Changes since v3:
- Fixed typo for CONFIG_MSI
- Added back the mutex code
- Rebase the patch on top of newly added WARN_ON().
- Remove the direct read of register VTCR_EL2.
- Fixed minor comments.
Changes since v4:
- Replace the ffsll() with ffs64() function.
- Add code to free resources when probe failed.
---
---
 MAINTAINERS                           |   6 +
 SUPPORT.md                            |   1 +
 xen/drivers/passthrough/Kconfig       |  11 +
 xen/drivers/passthrough/arm/Makefile  |   1 +
 xen/drivers/passthrough/arm/smmu-v3.c | 939 ++++++++++++++++++++++----
 5 files changed, 830 insertions(+), 128 deletions(-)

diff --git a/MAINTAINERS b/MAINTAINERS
index 5079b834c2..14240e8e1e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -249,6 +249,12 @@ F:	xen/include/asm-arm/
 F:	xen/include/public/arch-arm/
 F:	xen/include/public/arch-arm.h
 
+ARM SMMUv3
+M:	Bertrand Marquis <bertrand.marquis@arm.com>
+M:	Rahul Singh <rahul.singh@arm.com>
+S:	Supported
+F:	xen/drivers/passthrough/arm/smmu-v3.c
+
 Change Log
 M:	Paul Durrant <paul@xen.org>
 R:	Community Manager <community.manager@xenproject.org>
diff --git a/SUPPORT.md b/SUPPORT.md
index ab02aca5f4..5ee3c8651a 100644
--- a/SUPPORT.md
+++ b/SUPPORT.md
@@ -67,6 +67,7 @@ For the Cortex A57 r0p0 - r1p1, see Errata 832075.
     Status, Intel VT-d: Supported
     Status, ARM SMMUv1: Supported, not security supported
     Status, ARM SMMUv2: Supported, not security supported
+    Status, ARM SMMUv3: Tech Preview
     Status, Renesas IPMMU-VMSA: Supported, not security supported
 
 ### ARM/GICv3 ITS
diff --git a/xen/drivers/passthrough/Kconfig b/xen/drivers/passthrough/Kconfig
index 0036007ec4..341ba92b30 100644
--- a/xen/drivers/passthrough/Kconfig
+++ b/xen/drivers/passthrough/Kconfig
@@ -13,6 +13,17 @@ config ARM_SMMU
 	  Say Y here if your SoC includes an IOMMU device implementing the
 	  ARM SMMU architecture.
 
+config ARM_SMMU_V3
+	bool "ARM Ltd. System MMU Version 3 (SMMUv3) Support" if EXPERT
+	depends on ARM_64
+	---help---
+	 Support for implementations of the ARM System MMU architecture
+	 version 3. Driver is in experimental stage and should not be used in
+	 production.
+
+	 Say Y here if your system includes an IOMMU device implementing
+	 the ARM SMMUv3 architecture.
+
 config IPMMU_VMSA
 	bool "Renesas IPMMU-VMSA found in R-Car Gen3 SoCs"
 	depends on ARM_64
diff --git a/xen/drivers/passthrough/arm/Makefile b/xen/drivers/passthrough/arm/Makefile
index fcd918ea3e..c5fb3b58a5 100644
--- a/xen/drivers/passthrough/arm/Makefile
+++ b/xen/drivers/passthrough/arm/Makefile
@@ -1,3 +1,4 @@
 obj-y += iommu.o iommu_helpers.o iommu_fwspec.o
 obj-$(CONFIG_ARM_SMMU) += smmu.o
 obj-$(CONFIG_IPMMU_VMSA) += ipmmu-vmsa.o
+obj-$(CONFIG_ARM_SMMU_V3) += smmu-v3.o
diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
index 2dfadc6a65..dd0540bb5f 100644
--- a/xen/drivers/passthrough/arm/smmu-v3.c
+++ b/xen/drivers/passthrough/arm/smmu-v3.c
@@ -2,37 +2,263 @@
 /*
  * IOMMU API for ARM architected SMMUv3 implementations.
  *
+ * Based on Linux's SMMUv3 driver:
+ *    drivers/iommu/arm-smmu-v3.c
+ *    commit: ab435ce49bd1d02e33dfec24f76955dc1196970b
+ * and Xen's SMMU driver:
+ *    xen/drivers/passthrough/arm/smmu.c
+ *
+ * Major differences with regard to Linux driver are as follows:
+ *  1. Driver is currently supported as Tech Preview.
+ *  2. Only Stage-2 translation is supported as compared to the Linux driver
+ *     that supports both Stage-1 and Stage-2 translations.
+ *  3. Use P2M  page table instead of creating one as SMMUv3 has the
+ *     capability to share the page tables with the CPU.
+ *  4. Tasklets are used in place of threaded IRQ's in Linux for event queue
+ *     and priority queue IRQ handling.
+ *  5. Latest version of the Linux SMMUv3 code implements the commands queue
+ *     access functions based on atomic operations implemented in Linux.
+ *     Atomic functions used by the commands queue access functions are not
+ *     implemented in XEN therefore we decided to port the earlier version
+ *     of the code. Atomic operations are introduced to fix the bottleneck of
+ *     the SMMU command queue insertion operation. A new algorithm for
+ *     inserting commands into the queue is introduced, which is
+ *     lock-free on the fast-path.
+ *     Consequence of reverting the patch is that the command queue insertion
+ *     will be slow for large systems as spinlock will be used to serializes
+ *     accesses from all CPUs to the single queue supported by the hardware.
+ *     Once the proper atomic operations will be available in XEN the driver
+ *     can be updated.
+ *  6. Spin lock is used in place of Mutex when attaching a device to the SMMU,
+ *     as there is no blocking locks implementation available in XEN.This might
+ *     introduce latency in XEN. Need to investigate before driver is out for
+ *     Tech Preview.
+ *  7. PCI ATS functionality is not supported, as there is no support available
+ *     in XEN to test the functionality. Code is not tested and compiled. Code
+ *     is guarded by the flag CONFIG_PCI_ATS.
+ *  8. MSI interrupts are not supported as there is no support available
+ *     in XEN to request MSI interrupts. Code is not tested and compiled. Code
+ *     is guarded by the flag CONFIG_MSI.
+ *
+ * Following functionality should be supported before driver is out for tech
+ * preview
+ *
+ *  1. Investigate the timing analysis of using spin lock in place of mutex
+ *     when attaching devices to SMMU.
+ *  2. Merged the latest Linux SMMUv3 driver code once atomic operation is
+ *     available in XEN.
+ *  3. PCI ATS and MSI interrupts should be supported.
+ *  4. Investigate side-effect of using tasklet in place of threaded IRQ and
+ *     fix if any.
+ *
  * Copyright (C) 2015 ARM Limited
  *
  * Author: Will Deacon <will.deacon@arm.com>
  *
- * This driver is powered by bad coffee and bombay mix.
+ * Copyright (C) 2020 Arm Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
  */
 
-#include <linux/acpi.h>
-#include <linux/acpi_iort.h>
-#include <linux/bitfield.h>
-#include <linux/bitops.h>
-#include <linux/crash_dump.h>
-#include <linux/delay.h>
-#include <linux/dma-iommu.h>
-#include <linux/err.h>
-#include <linux/interrupt.h>
-#include <linux/io-pgtable.h>
-#include <linux/iommu.h>
-#include <linux/iopoll.h>
-#include <linux/module.h>
-#include <linux/msi.h>
-#include <linux/of.h>
-#include <linux/of_address.h>
-#include <linux/of_iommu.h>
-#include <linux/of_platform.h>
-#include <linux/pci.h>
-#include <linux/pci-ats.h>
-#include <linux/platform_device.h>
-
-#include <linux/amba/bus.h>
+#include <xen/acpi.h>
+#include <xen/config.h>
+#include <xen/delay.h>
+#include <xen/errno.h>
+#include <xen/err.h>
+#include <xen/irq.h>
+#include <xen/lib.h>
+#include <xen/list.h>
+#include <xen/mm.h>
+#include <xen/rbtree.h>
+#include <xen/sched.h>
+#include <xen/sizes.h>
+#include <xen/vmap.h>
+#include <asm/atomic.h>
+#include <asm/device.h>
+#include <asm/io.h>
+#include <asm/iommu_fwspec.h>
+#include <asm/platform.h>
+
+
+#define ARM_SMMU_VTCR_SH_IS		3
+#define ARM_SMMU_VTCR_RGN_WBWA		1
+#define ARM_SMMU_VTCR_TG0_4K		0
+#define ARM_SMMU_VTCR_PS_32_BIT		0x0ULL
+#define ARM_SMMU_VTCR_PS_36_BIT		0x1ULL
+#define ARM_SMMU_VTCR_PS_40_BIT		0x2ULL
+#define ARM_SMMU_VTCR_PS_42_BIT		0x3ULL
+#define ARM_SMMU_VTCR_PS_44_BIT		0x4ULL
+#define ARM_SMMU_VTCR_PS_48_BIT		0x5ULL
+#define ARM_SMMU_VTCR_PS_52_BIT		0x6ULL
+
+/* Linux compatibility functions. */
+typedef paddr_t		dma_addr_t;
+typedef paddr_t		phys_addr_t;
+typedef unsigned int		gfp_t;
+
+#define platform_device		device
+
+#define GFP_KERNEL		0
+
+/* Alias to Xen lock functions */
+#define mutex spinlock
+#define mutex_init spin_lock_init
+#define mutex_lock spin_lock
+#define mutex_unlock spin_unlock
+
+/* Device logger functions */
+#define dev_name(dev)	dt_node_full_name(dev->of_node)
+#define dev_dbg(dev, fmt, ...)			\
+	printk(XENLOG_DEBUG "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
+#define dev_notice(dev, fmt, ...)		\
+	printk(XENLOG_INFO "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
+#define dev_warn(dev, fmt, ...)			\
+	printk(XENLOG_WARNING "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
+#define dev_err(dev, fmt, ...)			\
+	printk(XENLOG_ERR "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
+#define dev_info(dev, fmt, ...)			\
+	printk(XENLOG_INFO "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
+#define dev_err_ratelimited(dev, fmt, ...)			\
+	printk(XENLOG_ERR "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
+
+/*
+ * Periodically poll an address and wait between reads in us until a
+ * condition is met or a timeout occurs.
+ *
+ * @return: 0 when cond met, -ETIMEDOUT upon timeout
+ */
+#define readx_poll_timeout(op, addr, val, cond, sleep_us, timeout_us) \
+({ \
+	s_time_t deadline = NOW() + MICROSECS(timeout_us); \
+	for (;;) { \
+		(val) = op(addr); \
+		if (cond) \
+			break; \
+		if (NOW() > deadline) { \
+			(val) = op(addr); \
+			break; \
+		} \
+		udelay(sleep_us); \
+	} \
+	(cond) ? 0 : -ETIMEDOUT; \
+})
+
+#define readl_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us)	\
+	readx_poll_timeout(readl_relaxed, addr, val, cond, delay_us, timeout_us)
+
+#define FIELD_PREP(_mask, _val)			\
+	(((typeof(_mask))(_val) << (ffs64(_mask) - 1)) & (_mask))
+
+#define FIELD_GET(_mask, _reg)			\
+	((typeof(_mask))(((_reg) & (_mask)) >> (ffs64(_mask) - 1)))
+
+/*
+ * Helpers for DMA allocation. Just the function name is reused for
+ * porting code, these allocation are not managed allocations
+ */
+static void *dmam_alloc_coherent(struct device *dev, size_t size,
+				paddr_t *dma_handle, gfp_t gfp)
+{
+	void *vaddr;
+	unsigned long alignment = size;
+
+	/*
+	 * _xzalloc requires that the (align & (align -1)) = 0. Most of the
+	 * allocations in SMMU code should send the right value for size. In
+	 * case this is not true print a warning and align to the size of a
+	 * (void *)
+	 */
+	if (size & (size - 1)) {
+		printk(XENLOG_WARNING "SMMUv3: Fixing alignment for the DMA buffer\n");
+		alignment = sizeof(void *);
+	}
+
+	vaddr = _xzalloc(size, alignment);
+	if (!vaddr) {
+		printk(XENLOG_ERR "SMMUv3: DMA allocation failed\n");
+		return NULL;
+	}
+
+	*dma_handle = virt_to_maddr(vaddr);
+
+	return vaddr;
+}
+
+
+/* Xen specific code. */
+struct iommu_domain {
+	/* Runtime SMMU configuration for this iommu_domain */
+	atomic_t		ref;
+	/*
+	 * Used to link iommu_domain contexts for a same domain.
+	 * There is at least one per-SMMU to used by the domain.
+	 */
+	struct list_head		list;
+};
+
+/* Describes information required for a Xen domain */
+struct arm_smmu_xen_domain {
+	spinlock_t		lock;
+
+	/* List of iommu domains associated to this domain */
+	struct list_head	contexts;
+};
+
+
+/* Keep a list of devices associated with this driver */
+static DEFINE_SPINLOCK(arm_smmu_devices_lock);
+static LIST_HEAD(arm_smmu_devices);
+
+static inline void *dev_iommu_priv_get(struct device *dev)
+{
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+
+	return fwspec && fwspec->iommu_priv ? fwspec->iommu_priv : NULL;
+}
+
+static inline void dev_iommu_priv_set(struct device *dev, void *priv)
+{
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+
+	fwspec->iommu_priv = priv;
+}
+
+static int platform_get_irq_byname_optional(struct device *dev,
+				const char *name)
+{
+	int index, ret;
+	struct dt_device_node *np  = dev_to_dt(dev);
+
+	if (unlikely(!name))
+		return -EINVAL;
+
+	index = dt_property_match_string(np, "interrupt-names", name);
+	if (index < 0) {
+		dev_info(dev, "IRQ %s not found\n", name);
+		return index;
+	}
+
+	ret = platform_get_irq(np, index);
+	if (ret < 0) {
+		dev_err(dev, "failed to get irq index %d\n", index);
+		return -ENODEV;
+	}
+
+	return ret;
+}
 
+/* Start of Linux SMMUv3 code */
 /* MMIO registers */
 #define ARM_SMMU_IDR0			0x0
 #define IDR0_ST_LVL			GENMASK(28, 27)
@@ -402,6 +628,7 @@ enum pri_resp {
 	PRI_RESP_SUCC = 2,
 };
 
+#ifdef CONFIG_MSI
 enum arm_smmu_msi_index {
 	EVTQ_MSI_INDEX,
 	GERROR_MSI_INDEX,
@@ -426,6 +653,7 @@ static phys_addr_t arm_smmu_msi_cfg[ARM_SMMU_MAX_MSIS][3] = {
 		ARM_SMMU_PRIQ_IRQ_CFG2,
 	},
 };
+#endif /* CONFIG_MSI */
 
 struct arm_smmu_cmdq_ent {
 	/* Common fields */
@@ -613,8 +841,13 @@ struct arm_smmu_device {
 		u64			padding;
 	};
 
-	/* IOMMU core code handle */
-	struct iommu_device		iommu;
+	/* Need to keep a list of SMMU devices */
+	struct list_head		devices;
+
+	/* Tasklets for handling evts/faults and pci page request IRQs*/
+	struct tasklet		evtq_irq_tasklet;
+	struct tasklet		priq_irq_tasklet;
+	struct tasklet		combined_irq_tasklet;
 };
 
 /* SMMU private data for each master */
@@ -646,6 +879,9 @@ struct arm_smmu_domain {
 	enum arm_smmu_domain_stage	stage;
 	struct arm_smmu_s2_cfg	s2_cfg;
 
+	/* Xen domain associated with this SMMU domain */
+	struct domain		*d;
+
 	struct iommu_domain		domain;
 
 	struct list_head		devices;
@@ -984,6 +1220,7 @@ static void arm_smmu_cmdq_issue_cmd(struct arm_smmu_device *smmu,
 	spin_unlock_irqrestore(&smmu->cmdq.lock, flags);
 }
 
+#ifdef CONFIG_MSI
 /*
  * The difference between val and sync_idx is bounded by the maximum size of
  * a queue at 2^20 entries, so 32 bits is plenty for wrap-safe arithmetic.
@@ -1027,6 +1264,13 @@ static int __arm_smmu_cmdq_issue_sync_msi(struct arm_smmu_device *smmu)
 
 	return __arm_smmu_sync_poll_msi(smmu, ent.sync.msidata);
 }
+#else
+static inline int __arm_smmu_cmdq_issue_sync_msi(struct arm_smmu_device *smmu)
+{
+	return 0;
+}
+#endif /* CONFIG_MSI */
+
 
 static int __arm_smmu_cmdq_issue_sync(struct arm_smmu_device *smmu)
 {
@@ -1069,7 +1313,7 @@ arm_smmu_write_strtab_l1_desc(__le64 *dst, struct arm_smmu_strtab_l1_desc *desc)
 	val |= desc->l2ptr_dma & STRTAB_L1_DESC_L2PTR_MASK;
 
 	/* See comment in arm_smmu_write_ctx_desc() */
-	WRITE_ONCE(*dst, cpu_to_le64(val));
+	write_atomic(dst, cpu_to_le64(val));
 }
 
 static void arm_smmu_sync_ste_for_sid(struct arm_smmu_device *smmu, u32 sid)
@@ -1184,7 +1428,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
 						 STRTAB_STE_1_EATS_TRANS));
 
 	arm_smmu_sync_ste_for_sid(smmu, sid);
-	WRITE_ONCE(dst[0], cpu_to_le64(val));
+	write_atomic(&dst[0], cpu_to_le64(val));
 	arm_smmu_sync_ste_for_sid(smmu, sid);
 
 	/* It's likely that we'll want to use the new STE soon */
@@ -1231,7 +1475,7 @@ static int arm_smmu_init_l2_strtab(struct arm_smmu_device *smmu, u32 sid)
 }
 
 /* IRQ and event handlers */
-static irqreturn_t arm_smmu_evtq_thread(int irq, void *dev)
+static void arm_smmu_evtq_tasklet(void *dev)
 {
 	int i;
 	struct arm_smmu_device *smmu = dev;
@@ -1261,7 +1505,6 @@ static irqreturn_t arm_smmu_evtq_thread(int irq, void *dev)
 	/* Sync our overflow flag, as we believe we're up to speed */
 	llq->cons = Q_OVF(llq->prod) | Q_WRP(llq, llq->cons) |
 		    Q_IDX(llq, llq->cons);
-	return IRQ_HANDLED;
 }
 
 static void arm_smmu_handle_ppr(struct arm_smmu_device *smmu, u64 *evt)
@@ -1302,7 +1545,7 @@ static void arm_smmu_handle_ppr(struct arm_smmu_device *smmu, u64 *evt)
 	}
 }
 
-static irqreturn_t arm_smmu_priq_thread(int irq, void *dev)
+static void arm_smmu_priq_tasklet(void *dev)
 {
 	struct arm_smmu_device *smmu = dev;
 	struct arm_smmu_queue *q = &smmu->priq.q;
@@ -1321,12 +1564,12 @@ static irqreturn_t arm_smmu_priq_thread(int irq, void *dev)
 	llq->cons = Q_OVF(llq->prod) | Q_WRP(llq, llq->cons) |
 		      Q_IDX(llq, llq->cons);
 	queue_sync_cons_out(q);
-	return IRQ_HANDLED;
 }
 
 static int arm_smmu_device_disable(struct arm_smmu_device *smmu);
 
-static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
+static void arm_smmu_gerror_handler(int irq, void *dev,
+				struct cpu_user_regs *regs)
 {
 	u32 gerror, gerrorn, active;
 	struct arm_smmu_device *smmu = dev;
@@ -1336,7 +1579,7 @@ static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
 
 	active = gerror ^ gerrorn;
 	if (!(active & GERROR_ERR_MASK))
-		return IRQ_NONE; /* No errors pending */
+		return; /* No errors pending */
 
 	dev_warn(smmu->dev,
 		 "unexpected global error reported (0x%08x), this could be serious\n",
@@ -1369,26 +1612,44 @@ static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
 		arm_smmu_cmdq_skip_err(smmu);
 
 	writel(gerror, smmu->base + ARM_SMMU_GERRORN);
-	return IRQ_HANDLED;
 }
 
-static irqreturn_t arm_smmu_combined_irq_thread(int irq, void *dev)
+static void arm_smmu_combined_irq_handler(int irq, void *dev,
+				struct cpu_user_regs *regs)
 {
 	struct arm_smmu_device *smmu = dev;
 
-	arm_smmu_evtq_thread(irq, dev);
+	arm_smmu_gerror_handler(irq, dev, regs);
+
+	tasklet_schedule(&(smmu->combined_irq_tasklet));
+}
+
+static void arm_smmu_combined_irq_tasklet(void *dev)
+{
+	struct arm_smmu_device *smmu = dev;
+
+	arm_smmu_evtq_tasklet(dev);
 	if (smmu->features & ARM_SMMU_FEAT_PRI)
-		arm_smmu_priq_thread(irq, dev);
+		arm_smmu_priq_tasklet(dev);
+}
+
+static void arm_smmu_evtq_irq_tasklet(int irq, void *dev,
+				struct cpu_user_regs *regs)
+{
+	struct arm_smmu_device *smmu = dev;
 
-	return IRQ_HANDLED;
+	tasklet_schedule(&(smmu->evtq_irq_tasklet));
 }
 
-static irqreturn_t arm_smmu_combined_irq_handler(int irq, void *dev)
+static void arm_smmu_priq_irq_tasklet(int irq, void *dev,
+				struct cpu_user_regs *regs)
 {
-	arm_smmu_gerror_handler(irq, dev);
-	return IRQ_WAKE_THREAD;
+	struct arm_smmu_device *smmu = dev;
+
+	tasklet_schedule(&(smmu->priq_irq_tasklet));
 }
 
+#ifdef CONFIG_PCI_ATS
 static void
 arm_smmu_atc_inv_to_cmd(int ssid, unsigned long iova, size_t size,
 			struct arm_smmu_cmdq_ent *cmd)
@@ -1495,6 +1756,7 @@ static int arm_smmu_atc_inv_domain(struct arm_smmu_domain *smmu_domain,
 
 	return ret ? -ETIMEDOUT : 0;
 }
+#endif /* CONFIG_PCI_ATS */
 
 static void arm_smmu_tlb_inv_context(void *cookie)
 {
@@ -1525,7 +1787,7 @@ static struct iommu_domain *arm_smmu_domain_alloc(void)
 	 * We can't really do anything meaningful until we've added a
 	 * master.
 	 */
-	smmu_domain = kzalloc(sizeof(*smmu_domain), GFP_KERNEL);
+	smmu_domain = xzalloc(struct arm_smmu_domain);
 	if (!smmu_domain)
 		return NULL;
 
@@ -1563,7 +1825,7 @@ static void arm_smmu_domain_free(struct iommu_domain *domain)
 	if (cfg->vmid)
 		arm_smmu_bitmap_free(smmu->vmid_map, cfg->vmid);
 
-	kfree(smmu_domain);
+	xfree(smmu_domain);
 }
 
 
@@ -1576,6 +1838,44 @@ static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
 	struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
 	typeof(&arm_lpae_s2_cfg.vtcr) vtcr = &arm_lpae_s2_cfg.vtcr;
 
+	vtcr->sh = ARM_SMMU_VTCR_SH_IS;
+	vtcr->irgn = ARM_SMMU_VTCR_RGN_WBWA;
+	vtcr->orgn = ARM_SMMU_VTCR_RGN_WBWA;
+
+	BUILD_BUG_ON(PAGE_SIZE != SZ_4K);
+	vtcr->tg = ARM_SMMU_VTCR_TG0_4K;
+
+	switch (smmu->oas) {
+	case 32:
+		vtcr->ps = ARM_SMMU_VTCR_PS_32_BIT;
+		break;
+	case 36:
+		vtcr->ps = ARM_SMMU_VTCR_PS_36_BIT;
+		break;
+	case 40:
+		vtcr->ps = ARM_SMMU_VTCR_PS_40_BIT;
+		break;
+	case 42:
+		vtcr->ps = ARM_SMMU_VTCR_PS_42_BIT;
+		break;
+	case 44:
+		vtcr->ps = ARM_SMMU_VTCR_PS_44_BIT;
+		break;
+	case 48:
+		vtcr->ps = ARM_SMMU_VTCR_PS_48_BIT;
+		break;
+	case 52:
+		vtcr->ps = ARM_SMMU_VTCR_PS_52_BIT;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	vtcr->tsz = 64 - p2m_ipa_bits;
+	vtcr->sl = 2 - P2M_ROOT_LEVEL;
+
+	arm_lpae_s2_cfg.vttbr  = page_to_maddr(smmu_domain->d->arch.p2m.root);
+
 	vmid = arm_smmu_bitmap_alloc(smmu->vmid_map, smmu->vmid_bits);
 	if (vmid < 0)
 		return vmid;
@@ -1589,6 +1889,11 @@ static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
 			  FIELD_PREP(STRTAB_STE_2_VTCR_S2SH0, vtcr->sh) |
 			  FIELD_PREP(STRTAB_STE_2_VTCR_S2TG, vtcr->tg) |
 			  FIELD_PREP(STRTAB_STE_2_VTCR_S2PS, vtcr->ps);
+
+	printk(XENLOG_DEBUG
+		   "SMMUv3: d%u: vmid 0x%x vtcr 0x%"PRIpaddr" p2maddr 0x%"PRIpaddr"\n",
+		   smmu_domain->d->domain_id, cfg->vmid, cfg->vtcr, cfg->vttbr);
+
 	return 0;
 }
 
@@ -1650,6 +1955,7 @@ static void arm_smmu_install_ste_for_dev(struct arm_smmu_master *master)
 	}
 }
 
+#ifdef CONFIG_PCI_ATS
 static bool arm_smmu_ats_supported(struct arm_smmu_master *master)
 {
 	struct device *dev = master->dev;
@@ -1748,6 +2054,23 @@ static void arm_smmu_disable_pasid(struct arm_smmu_master *master)
 
 	pci_disable_pasid(pdev);
 }
+#else
+static inline bool arm_smmu_ats_supported(struct arm_smmu_master *master)
+{
+	return false;
+}
+
+static inline void arm_smmu_enable_ats(struct arm_smmu_master *master) { }
+
+static inline void arm_smmu_disable_ats(struct arm_smmu_master *master) { }
+
+static inline int arm_smmu_enable_pasid(struct arm_smmu_master *master)
+{
+	return 0;
+}
+
+static inline void arm_smmu_disable_pasid(struct arm_smmu_master *master) { }
+#endif /* CONFIG_PCI_ATS */
 
 static void arm_smmu_detach_dev(struct arm_smmu_master *master)
 {
@@ -1830,8 +2153,10 @@ static bool arm_smmu_sid_in_range(struct arm_smmu_device *smmu, u32 sid)
 
 	return sid < limit;
 }
+/* Forward declaration */
+static struct arm_smmu_device *arm_smmu_get_by_dev(struct device *dev);
 
-static struct iommu_device *arm_smmu_probe_device(struct device *dev)
+static int arm_smmu_add_device(u8 devfn, struct device *dev)
 {
 	int i, ret;
 	struct arm_smmu_device *smmu;
@@ -1839,14 +2164,15 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 
 	if (!fwspec)
-		return ERR_PTR(-ENODEV);
+		return -ENODEV;
 
-	if (WARN_ON_ONCE(dev_iommu_priv_get(dev)))
-		return ERR_PTR(-EBUSY);
+	smmu = arm_smmu_get_by_dev(fwspec->iommu_dev);
+	if (!smmu)
+		return -ENODEV;
 
-	master = kzalloc(sizeof(*master), GFP_KERNEL);
+	master = xzalloc(struct arm_smmu_master);
 	if (!master)
-		return ERR_PTR(-ENOMEM);
+		return -ENOMEM;
 
 	master->dev = dev;
 	master->smmu = smmu;
@@ -1881,17 +2207,36 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
 	 */
 	arm_smmu_enable_pasid(master);
 
-	return &smmu->iommu;
+	return 0;
 
 err_free_master:
-	kfree(master);
+	xfree(master);
 	dev_iommu_priv_set(dev, NULL);
-	return ERR_PTR(ret);
+	return ret;
 }
 
-static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args)
+static int arm_smmu_dt_xlate(struct device *dev,
+				const struct dt_phandle_args *args)
 {
-	return iommu_fwspec_add_ids(dev, args->args, 1);
+	int ret;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+
+	ret = iommu_fwspec_add_ids(dev, args->args, 1);
+	if (ret)
+		return ret;
+
+	if (dt_device_is_protected(dev_to_dt(dev))) {
+		dev_err(dev, "Already added to SMMUv3\n");
+		return -EEXIST;
+	}
+
+	/* Let Xen know that the master device is protected by an IOMMU. */
+	dt_device_set_protected(dev_to_dt(dev));
+
+	dev_info(dev, "Added master device (SMMUv3 %s StreamIds %u)\n",
+			dev_name(fwspec->iommu_dev), fwspec->num_ids);
+
+	return 0;
 }
 
 /* Probing and initialisation functions */
@@ -1972,7 +2317,7 @@ static int arm_smmu_init_l1_strtab(struct arm_smmu_device *smmu)
 	size_t size = sizeof(*cfg->l1_desc) * cfg->num_l1_ents;
 	void *strtab = smmu->strtab_cfg.strtab;
 
-	cfg->l1_desc = devm_kzalloc(smmu->dev, size, GFP_KERNEL);
+	cfg->l1_desc = _xzalloc(size, sizeof(void *));
 	if (!cfg->l1_desc) {
 		dev_err(smmu->dev, "failed to allocate l1 stream table desc\n");
 		return -ENOMEM;
@@ -2118,6 +2463,7 @@ static int arm_smmu_update_gbpa(struct arm_smmu_device *smmu, u32 set, u32 clr)
 	return ret;
 }
 
+#ifdef CONFIG_MSI
 static void arm_smmu_free_msis(void *data)
 {
 	struct device *dev = data;
@@ -2188,8 +2534,35 @@ static void arm_smmu_setup_msis(struct arm_smmu_device *smmu)
 	/* Add callback to free MSIs on teardown */
 	devm_add_action(dev, arm_smmu_free_msis, dev);
 }
+#else
+static inline void arm_smmu_setup_msis(struct arm_smmu_device *smmu) { }
+#endif /* CONFIG_MSI */
 
-static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
+static void arm_smmu_free_irqs(struct arm_smmu_device *smmu)
+{
+	int irq;
+
+	irq = smmu->combined_irq;
+	if (irq)
+		release_irq(irq, smmu);
+	else {
+		irq = smmu->evtq.q.irq;
+		if (irq)
+			release_irq(irq, smmu);
+
+		irq = smmu->gerr_irq;
+		if (irq)
+			release_irq(irq, smmu);
+
+		if (smmu->features & ARM_SMMU_FEAT_PRI) {
+			irq = smmu->priq.q.irq;
+			if (irq)
+				release_irq(irq, smmu);
+		}
+	}
+}
+
+static int arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
 {
 	int irq, ret;
 
@@ -2198,22 +2571,24 @@ static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
 	/* Request interrupt lines */
 	irq = smmu->evtq.q.irq;
 	if (irq) {
-		ret = devm_request_threaded_irq(smmu->dev, irq, NULL,
-						arm_smmu_evtq_thread,
-						IRQF_ONESHOT,
+		ret = request_irq(irq, 0, arm_smmu_evtq_irq_tasklet,
 						"arm-smmu-v3-evtq", smmu);
-		if (ret < 0)
+		if (ret < 0) {
 			dev_warn(smmu->dev, "failed to enable evtq irq\n");
+			return ret;
+		}
 	} else {
 		dev_warn(smmu->dev, "no evtq irq - events will not be reported!\n");
 	}
 
 	irq = smmu->gerr_irq;
 	if (irq) {
-		ret = devm_request_irq(smmu->dev, irq, arm_smmu_gerror_handler,
-				       0, "arm-smmu-v3-gerror", smmu);
-		if (ret < 0)
+		ret = request_irq(irq, 0, arm_smmu_gerror_handler,
+						"arm-smmu-v3-gerror", smmu);
+		if (ret < 0) {
 			dev_warn(smmu->dev, "failed to enable gerror irq\n");
+			goto err_free_evtq_irq;
+		}
 	} else {
 		dev_warn(smmu->dev, "no gerr irq - errors will not be reported!\n");
 	}
@@ -2221,18 +2596,30 @@ static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
 	if (smmu->features & ARM_SMMU_FEAT_PRI) {
 		irq = smmu->priq.q.irq;
 		if (irq) {
-			ret = devm_request_threaded_irq(smmu->dev, irq, NULL,
-							arm_smmu_priq_thread,
-							IRQF_ONESHOT,
-							"arm-smmu-v3-priq",
-							smmu);
-			if (ret < 0)
+			ret = request_irq(irq, 0, arm_smmu_priq_irq_tasklet,
+							"arm-smmu-v3-priq", smmu);
+			if (ret < 0) {
 				dev_warn(smmu->dev,
 					 "failed to enable priq irq\n");
+				goto err_free_gerr_irq;
+			}
 		} else {
 			dev_warn(smmu->dev, "no priq irq - PRI will be broken\n");
 		}
 	}
+
+	return 0;
+
+err_free_gerr_irq:
+	irq = smmu->gerr_irq;
+	if (irq)
+		release_irq(irq, smmu);
+err_free_evtq_irq:
+	irq = smmu->evtq.q.irq;
+	if (irq)
+		release_irq(irq, smmu);
+
+	return ret;
 }
 
 static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
@@ -2254,15 +2641,19 @@ static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
 		 * Cavium ThunderX2 implementation doesn't support unique irq
 		 * lines. Use a single irq line for all the SMMUv3 interrupts.
 		 */
-		ret = devm_request_threaded_irq(smmu->dev, irq,
-					arm_smmu_combined_irq_handler,
-					arm_smmu_combined_irq_thread,
-					IRQF_ONESHOT,
-					"arm-smmu-v3-combined-irq", smmu);
-		if (ret < 0)
+		ret = request_irq(irq, 0, arm_smmu_combined_irq_handler,
+						"arm-smmu-v3-combined-irq", smmu);
+		if (ret < 0) {
 			dev_warn(smmu->dev, "failed to enable combined irq\n");
-	} else
-		arm_smmu_setup_unique_irqs(smmu);
+			return ret;
+		}
+	} else {
+		ret = arm_smmu_setup_unique_irqs(smmu);
+		if (ret) {
+			dev_warn(smmu->dev, "failed to setup unique irqs\n");
+			return ret;
+		}
+	}
 
 	if (smmu->features & ARM_SMMU_FEAT_PRI)
 		irqen_flags |= IRQ_CTRL_PRIQ_IRQEN;
@@ -2270,10 +2661,16 @@ static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
 	/* Enable interrupt generation on the SMMU */
 	ret = arm_smmu_write_reg_sync(smmu, irqen_flags,
 				      ARM_SMMU_IRQ_CTRL, ARM_SMMU_IRQ_CTRLACK);
-	if (ret)
+	if (ret) {
 		dev_warn(smmu->dev, "failed to enable irqs\n");
+		goto err_free_irqs;
+	}
 
 	return 0;
+
+err_free_irqs:
+	arm_smmu_free_irqs(smmu);
+	return ret;
 }
 
 static int arm_smmu_device_disable(struct arm_smmu_device *smmu)
@@ -2287,7 +2684,7 @@ static int arm_smmu_device_disable(struct arm_smmu_device *smmu)
 	return ret;
 }
 
-static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
+static int arm_smmu_device_reset(struct arm_smmu_device *smmu)
 {
 	int ret;
 	u32 reg, enables;
@@ -2297,7 +2694,7 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
 	reg = readl_relaxed(smmu->base + ARM_SMMU_CR0);
 	if (reg & CR0_SMMUEN) {
 		dev_warn(smmu->dev, "SMMU currently enabled! Resetting...\n");
-		WARN_ON(is_kdump_kernel() && !disable_bypass);
+		WARN_ON(!disable_bypass);
 		arm_smmu_update_gbpa(smmu, GBPA_ABORT, 0);
 	}
 
@@ -2401,25 +2798,32 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
 		return ret;
 	}
 
-	if (is_kdump_kernel())
-		enables &= ~(CR0_EVTQEN | CR0_PRIQEN);
+	/* Initialize tasklets for threaded IRQs*/
+	tasklet_init(&smmu->evtq_irq_tasklet, arm_smmu_evtq_tasklet, smmu);
+	tasklet_init(&smmu->priq_irq_tasklet, arm_smmu_priq_tasklet, smmu);
+	tasklet_init(&smmu->combined_irq_tasklet, arm_smmu_combined_irq_tasklet,
+				 smmu);
 
 	/* Enable the SMMU interface, or ensure bypass */
-	if (!bypass || disable_bypass) {
+	if (disable_bypass) {
 		enables |= CR0_SMMUEN;
 	} else {
 		ret = arm_smmu_update_gbpa(smmu, 0, GBPA_ABORT);
 		if (ret)
-			return ret;
+			goto err_free_irqs;
 	}
 	ret = arm_smmu_write_reg_sync(smmu, enables, ARM_SMMU_CR0,
 				      ARM_SMMU_CR0ACK);
 	if (ret) {
 		dev_err(smmu->dev, "failed to enable SMMU interface\n");
-		return ret;
+		goto err_free_irqs;
 	}
 
 	return 0;
+
+err_free_irqs:
+	arm_smmu_free_irqs(smmu);
+	return ret;
 }
 
 static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
@@ -2470,8 +2874,10 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 	if (reg & IDR0_SEV)
 		smmu->features |= ARM_SMMU_FEAT_SEV;
 
+#ifdef CONFIG_MSI
 	if (reg & IDR0_MSI)
 		smmu->features |= ARM_SMMU_FEAT_MSI;
+#endif
 
 	if (reg & IDR0_HYP)
 		smmu->features |= ARM_SMMU_FEAT_HYP;
@@ -2496,7 +2902,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 		smmu->features |= ARM_SMMU_FEAT_TRANS_S2;
 
 	if (!(reg & IDR0_S2P)) {
-		dev_err(smmu->dev, "no translation support!\n");
+		dev_err(smmu->dev, "no stage-2 translation support!\n");
 		return -ENXIO;
 	}
 
@@ -2593,8 +2999,12 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
 		smmu->oas = 48;
 	}
 
+	smmu->oas = min_t(unsigned long, PADDR_BITS, smmu->oas);
 	smmu->ias = max(smmu->ias, smmu->oas);
 
+	/* Xen: Set maximum Stage-2 input size supported by the SMMU. */
+	p2m_restrict_ipa_bits(smmu->ias);
+
 	dev_info(smmu->dev, "ias %lu-bit, oas %lu-bit (features 0x%08x)\n",
 		 smmu->ias, smmu->oas, smmu->features);
 	return 0;
@@ -2645,7 +3055,7 @@ static inline int arm_smmu_device_acpi_probe(struct platform_device *pdev,
 static int arm_smmu_device_dt_probe(struct platform_device *pdev,
 				    struct arm_smmu_device *smmu)
 {
-	struct device *dev = &pdev->dev;
+	struct device *dev = pdev;
 	u32 cells;
 	int ret = -EINVAL;
 
@@ -2658,7 +3068,7 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev,
 
 	parse_driver_options(smmu);
 
-	if (of_dma_is_coherent(dev->of_node))
+	if (dt_get_property(dev->of_node, "dma-coherent", NULL))
 		smmu->features |= ARM_SMMU_FEAT_COHERENCY;
 
 	return ret;
@@ -2672,66 +3082,76 @@ static unsigned long arm_smmu_resource_size(struct arm_smmu_device *smmu)
 		return SZ_128K;
 }
 
-static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
-				      resource_size_t size)
+
+static void arm_smmu_free_structures(struct arm_smmu_device *smmu)
 {
-	struct resource res = {
-		.flags = IORESOURCE_MEM,
-		.start = start,
-		.end = start + size - 1,
-	};
+	if (smmu->cmdq.q.base)
+		xfree(smmu->cmdq.q.base);
+
+	if (smmu->evtq.q.base)
+		xfree(smmu->evtq.q.base);
 
-	return devm_ioremap_resource(dev, &res);
+	if (smmu->priq.q.base)
+		xfree(smmu->priq.q.base);
+
+	if (smmu->strtab_cfg.strtab)
+		xfree(smmu->strtab_cfg.strtab);
+
+	if (smmu->strtab_cfg.l1_desc)
+		xfree(smmu->strtab_cfg.l1_desc);
 }
 
 static int arm_smmu_device_probe(struct platform_device *pdev)
 {
 	int irq, ret;
-	struct resource *res;
-	resource_size_t ioaddr;
+	paddr_t ioaddr, iosize;
 	struct arm_smmu_device *smmu;
-	struct device *dev = &pdev->dev;
-	bool bypass;
 
-	smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
+	smmu = xzalloc(struct arm_smmu_device);
 	if (!smmu) {
-		dev_err(dev, "failed to allocate arm_smmu_device\n");
+		dev_err(pdev, "failed to allocate arm_smmu_device\n");
 		return -ENOMEM;
 	}
-	smmu->dev = dev;
+	smmu->dev = pdev;
 
-	if (dev->of_node) {
+	if (pdev->of_node) {
 		ret = arm_smmu_device_dt_probe(pdev, smmu);
+		if (ret)
+			goto out_free_smmu;
 	} else {
 		ret = arm_smmu_device_acpi_probe(pdev, smmu);
 		if (ret == -ENODEV)
-			return ret;
+			goto out_free_smmu;
 	}
 
-	/* Set bypass mode according to firmware probing result */
-	bypass = !!ret;
-
 	/* Base address */
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (resource_size(res) < arm_smmu_resource_size(smmu)) {
-		dev_err(dev, "MMIO region too small (%pr)\n", res);
-		return -EINVAL;
+	ret = dt_device_get_address(dev_to_dt(pdev), 0, &ioaddr, &iosize);
+	if (ret)
+		goto out_free_smmu;
+
+	if (iosize < arm_smmu_resource_size(smmu)) {
+		dev_err(pdev, "MMIO region too small (%lx)\n", iosize);
+		ret = -EINVAL;
+		goto out_free_smmu;
 	}
-	ioaddr = res->start;
 
 	/*
 	 * Don't map the IMPLEMENTATION DEFINED regions, since they may contain
-	 * the PMCG registers which are reserved by the PMU driver.
+	 * the PMCG registers which are optional and currently not supported.
 	 */
-	smmu->base = arm_smmu_ioremap(dev, ioaddr, ARM_SMMU_REG_SZ);
-	if (IS_ERR(smmu->base))
-		return PTR_ERR(smmu->base);
+	smmu->base = ioremap_nocache(ioaddr, ARM_SMMU_REG_SZ);
+	if (IS_ERR(smmu->base)) {
+		ret = PTR_ERR(smmu->base);
+		goto out_free_smmu;
+	}
 
-	if (arm_smmu_resource_size(smmu) > SZ_64K) {
-		smmu->page1 = arm_smmu_ioremap(dev, ioaddr + SZ_64K,
+	if (iosize > SZ_64K) {
+		smmu->page1 = ioremap_nocache(ioaddr + SZ_64K,
 					       ARM_SMMU_REG_SZ);
-		if (IS_ERR(smmu->page1))
-			return PTR_ERR(smmu->page1);
+		if (IS_ERR(smmu->page1)) {
+			ret = PTR_ERR(smmu->page1);
+			goto out_free;
+		}
 	} else {
 		smmu->page1 = smmu->base;
 	}
@@ -2756,23 +3176,286 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 	}
 	/* Probe the h/w */
 	ret = arm_smmu_device_hw_probe(smmu);
-	if (ret)
-		return ret;
+	if (ret) {
+		ret = -ENODEV;
+		goto out_free;
+	}
 
 	/* Initialise in-memory data structures */
 	ret = arm_smmu_init_structures(smmu);
 	if (ret)
-		return ret;
+		goto out_free;
 
 	/* Reset the device */
-	ret = arm_smmu_device_reset(smmu, bypass);
+	ret = arm_smmu_device_reset(smmu);
 	if (ret)
-		return ret;
+		goto out_free;
+
+	/*
+	 * Keep a list of all probed devices. This will be used to query
+	 * the smmu devices based on the fwnode.
+	 */
+	INIT_LIST_HEAD(&smmu->devices);
+
+	spin_lock(&arm_smmu_devices_lock);
+	list_add(&smmu->devices, &arm_smmu_devices);
+	spin_unlock(&arm_smmu_devices_lock);
 
 	return 0;
+
+
+out_free:
+	arm_smmu_free_structures(smmu);
+	if (smmu->page1)
+		iounmap(smmu->page1);
+	if (smmu->base)
+		iounmap(smmu->base);
+
+out_free_smmu:
+	xfree(smmu);
+
+	return ret;
 }
 
-static const struct of_device_id arm_smmu_of_match[] = {
+static const struct dt_device_match arm_smmu_of_match[] = {
 	{ .compatible = "arm,smmu-v3", },
 	{ },
 };
+
+/* Start of Xen specific code. */
+static int __must_check arm_smmu_iotlb_flush_all(struct domain *d)
+{
+	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
+	struct iommu_domain *io_domain;
+
+	spin_lock(&xen_domain->lock);
+
+	list_for_each_entry(io_domain, &xen_domain->contexts, list) {
+		/*
+		 * Only invalidate the context when SMMU is present.
+		 * This is because the context initialization is delayed
+		 * until a master has been added.
+		 */
+		if (unlikely(!ACCESS_ONCE(to_smmu_domain(io_domain)->smmu)))
+			continue;
+
+		arm_smmu_tlb_inv_context(to_smmu_domain(io_domain));
+	}
+
+	spin_unlock(&xen_domain->lock);
+
+	return 0;
+}
+
+static int __must_check arm_smmu_iotlb_flush(struct domain *d, dfn_t dfn,
+				unsigned long page_count, unsigned int flush_flags)
+{
+	return arm_smmu_iotlb_flush_all(d);
+}
+
+static struct arm_smmu_device *arm_smmu_get_by_dev(struct device *dev)
+{
+	struct arm_smmu_device *smmu = NULL;
+
+	spin_lock(&arm_smmu_devices_lock);
+
+	list_for_each_entry(smmu, &arm_smmu_devices, devices) {
+		if (smmu->dev  == dev) {
+			spin_unlock(&arm_smmu_devices_lock);
+			return smmu;
+		}
+	}
+
+	spin_unlock(&arm_smmu_devices_lock);
+
+	return NULL;
+}
+
+static struct iommu_domain *arm_smmu_get_domain(struct domain *d,
+				struct device *dev)
+{
+	struct iommu_domain *io_domain;
+	struct arm_smmu_domain *smmu_domain;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
+	struct arm_smmu_device *smmu = arm_smmu_get_by_dev(fwspec->iommu_dev);
+
+	if (!smmu)
+		return NULL;
+
+	/*
+	 * Loop through the &xen_domain->contexts to locate a context
+	 * assigned to this SMMU
+	 */
+	list_for_each_entry(io_domain, &xen_domain->contexts, list) {
+		smmu_domain = to_smmu_domain(io_domain);
+		if (smmu_domain->smmu == smmu)
+			return io_domain;
+	}
+	return NULL;
+}
+
+static void arm_smmu_destroy_iommu_domain(struct iommu_domain *io_domain)
+{
+	list_del(&io_domain->list);
+	arm_smmu_domain_free(io_domain);
+}
+
+static int arm_smmu_assign_dev(struct domain *d, u8 devfn,
+		struct device *dev, u32 flag)
+{
+	int ret = 0;
+	struct iommu_domain *io_domain;
+	struct arm_smmu_domain *smmu_domain;
+	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
+
+	spin_lock(&xen_domain->lock);
+
+	/*
+	 * Check to see if an iommu_domain already exists for this xen domain
+	 * under the same SMMU
+	 */
+	io_domain = arm_smmu_get_domain(d, dev);
+	if (!io_domain) {
+		io_domain = arm_smmu_domain_alloc();
+		if (!io_domain) {
+			ret = -ENOMEM;
+			goto out;
+		}
+		smmu_domain = to_smmu_domain(io_domain);
+		smmu_domain->d = d;
+
+		/* Chain the new context to the domain */
+		list_add(&io_domain->list, &xen_domain->contexts);
+	}
+
+	ret = arm_smmu_attach_dev(io_domain, dev);
+	if (ret) {
+		if (io_domain->ref.counter == 0)
+			arm_smmu_destroy_iommu_domain(io_domain);
+	} else {
+		atomic_inc(&io_domain->ref);
+	}
+
+out:
+	spin_unlock(&xen_domain->lock);
+	return ret;
+}
+
+static int arm_smmu_deassign_dev(struct domain *d, struct device *dev)
+{
+	struct iommu_domain *io_domain = arm_smmu_get_domain(d, dev);
+	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(io_domain);
+	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
+
+	if (!smmu_domain || smmu_domain->d != d) {
+		dev_err(dev, " not attached to domain %d\n", d->domain_id);
+		return -ESRCH;
+	}
+
+	spin_lock(&xen_domain->lock);
+
+	arm_smmu_detach_dev(master);
+	atomic_dec(&io_domain->ref);
+
+	if (io_domain->ref.counter == 0)
+		arm_smmu_destroy_iommu_domain(io_domain);
+
+	spin_unlock(&xen_domain->lock);
+
+	return 0;
+}
+
+static int arm_smmu_reassign_dev(struct domain *s, struct domain *t,
+				u8 devfn,  struct device *dev)
+{
+	int ret = 0;
+
+	/* Don't allow remapping on other domain than hwdom */
+	if (t && t != hardware_domain)
+		return -EPERM;
+
+	if (t == s)
+		return 0;
+
+	ret = arm_smmu_deassign_dev(s, dev);
+	if (ret)
+		return ret;
+
+	if (t) {
+		/* No flags are defined for ARM. */
+		ret = arm_smmu_assign_dev(t, devfn, dev, 0);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int arm_smmu_iommu_xen_domain_init(struct domain *d)
+{
+	struct arm_smmu_xen_domain *xen_domain;
+
+	xen_domain = xzalloc(struct arm_smmu_xen_domain);
+	if (!xen_domain)
+		return -ENOMEM;
+
+	spin_lock_init(&xen_domain->lock);
+	INIT_LIST_HEAD(&xen_domain->contexts);
+
+	dom_iommu(d)->arch.priv = xen_domain;
+	return 0;
+
+}
+
+static void __hwdom_init arm_smmu_iommu_hwdom_init(struct domain *d)
+{
+}
+
+static void arm_smmu_iommu_xen_domain_teardown(struct domain *d)
+{
+	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
+
+	ASSERT(list_empty(&xen_domain->contexts));
+	xfree(xen_domain);
+}
+
+static const struct iommu_ops arm_smmu_iommu_ops = {
+	.init		= arm_smmu_iommu_xen_domain_init,
+	.hwdom_init		= arm_smmu_iommu_hwdom_init,
+	.teardown		= arm_smmu_iommu_xen_domain_teardown,
+	.iotlb_flush		= arm_smmu_iotlb_flush,
+	.iotlb_flush_all	= arm_smmu_iotlb_flush_all,
+	.assign_device		= arm_smmu_assign_dev,
+	.reassign_device	= arm_smmu_reassign_dev,
+	.map_page		= arm_iommu_map_page,
+	.unmap_page		= arm_iommu_unmap_page,
+	.dt_xlate		= arm_smmu_dt_xlate,
+	.add_device		= arm_smmu_add_device,
+};
+
+static __init int arm_smmu_dt_init(struct dt_device_node *dev,
+				const void *data)
+{
+	int rc;
+
+	/*
+	 * Even if the device can't be initialized, we don't want to
+	 * give the SMMU device to dom0.
+	 */
+	dt_device_set_used_by(dev, DOMID_XEN);
+
+	rc = arm_smmu_device_probe(dt_to_dev(dev));
+	if (rc)
+		return rc;
+
+	iommu_set_ops(&arm_smmu_iommu_ops);
+
+	return 0;
+}
+
+DT_DEVICE_START(smmuv3, "ARM SMMU V3", DEVICE_IOMMU)
+.dt_match = arm_smmu_of_match,
+.init = arm_smmu_dt_init,
+DT_DEVICE_END
-- 
2.17.1



^ permalink raw reply related	[flat|nested] 24+ messages in thread

* Re: [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver
  2021-01-20 14:52 ` [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver Rahul Singh
@ 2021-01-20 15:35   ` Bertrand Marquis
  2021-01-20 20:31   ` Stefano Stabellini
  2021-01-20 21:33   ` Oleksandr
  2 siblings, 0 replies; 24+ messages in thread
From: Bertrand Marquis @ 2021-01-20 15:35 UTC (permalink / raw)
  To: Rahul Singh
  Cc: Xen-devel, Andrew Cooper, George Dunlap, Ian Jackson,
	Jan Beulich, Julien Grall, Stefano Stabellini, Wei Liu,
	Paul Durrant, Volodymyr Babchuk

Hi Rahul,

> On 20 Jan 2021, at 14:52, Rahul Singh <Rahul.Singh@arm.com> wrote:
> 
> Add support for ARM architected SMMUv3 implementation. It is based on
> the Linux SMMUv3 driver.
> 
> Driver is currently supported as Tech Preview.
> 
> Major differences with regard to Linux driver are as follows:
> 2. Only Stage-2 translation is supported as compared to the Linux driver
>   that supports both Stage-1 and Stage-2 translations.
> 3. Use P2M  page table instead of creating one as SMMUv3 has the
>   capability to share the page tables with the CPU.
> 4. Tasklets are used in place of threaded IRQ's in Linux for event queue
>   and priority queue IRQ handling.
> 5. Latest version of the Linux SMMUv3 code implements the commands queue
>   access functions based on atomic operations implemented in Linux.
>   Atomic functions used by the commands queue access functions are not
>   implemented in XEN therefore we decided to port the earlier version
>   of the code. Atomic operations are introduced to fix the bottleneck
>   of the SMMU command queue insertion operation. A new algorithm for
>   inserting commands into the queue is introduced, which is lock-free
>   on the fast-path.
>   Consequence of reverting the patch is that the command queue
>   insertion will be slow for large systems as spinlock will be used to
>   serializes accesses from all CPUs to the single queue supported by
>   the hardware. Once the proper atomic operations will be available in
>   XEN the driver can be updated.
> 6. Spin lock is used in place of mutex when attaching a device to the
>   SMMU, as there is no blocking locks implementation available in XEN.
>   This might introduce latency in XEN. Need to investigate before
>   driver is out for tech preview.
> 7. PCI ATS functionality is not supported, as there is no support
>   available in XEN to test the functionality. Code is not tested and
>   compiled. Code is guarded by the flag CONFIG_PCI_ATS.
> 8. MSI interrupts are not supported as there is no support available in
>   XEN to request MSI interrupts. Code is not tested and compiled. Code
>   is guarded by the flag CONFIG_MSI.
> 
> Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>

Cheers
Bertrand

> ---
> Changes since v2:
> - added return statement for readx_poll_timeout function.
> - remove iommu_get_dma_cookie and iommu_put_dma_cookie.
> - remove struct arm_smmu_xen_device as not required.
> - move dt_property_match_string to device_tree.c file.
> - replace arm_smmu_*_thread to arm_smmu_*_tasklet to avoid confusion.
> - use ARM_SMMU_REG_SZ as size when map memory to XEN.
> - remove bypass keyword to make sure when device-tree probe is failed we
>  are reporting error and not continuing to configure SMMU in bypass
>  mode.
> - fixed minor comments.
> Changes since v3:
> - Fixed typo for CONFIG_MSI
> - Added back the mutex code
> - Rebase the patch on top of newly added WARN_ON().
> - Remove the direct read of register VTCR_EL2.
> - Fixed minor comments.
> Changes since v4:
> - Replace the ffsll() with ffs64() function.
> - Add code to free resources when probe failed.
> ---
> ---
> MAINTAINERS                           |   6 +
> SUPPORT.md                            |   1 +
> xen/drivers/passthrough/Kconfig       |  11 +
> xen/drivers/passthrough/arm/Makefile  |   1 +
> xen/drivers/passthrough/arm/smmu-v3.c | 939 ++++++++++++++++++++++----
> 5 files changed, 830 insertions(+), 128 deletions(-)
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 5079b834c2..14240e8e1e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -249,6 +249,12 @@ F:	xen/include/asm-arm/
> F:	xen/include/public/arch-arm/
> F:	xen/include/public/arch-arm.h
> 
> +ARM SMMUv3
> +M:	Bertrand Marquis <bertrand.marquis@arm.com>
> +M:	Rahul Singh <rahul.singh@arm.com>
> +S:	Supported
> +F:	xen/drivers/passthrough/arm/smmu-v3.c
> +
> Change Log
> M:	Paul Durrant <paul@xen.org>
> R:	Community Manager <community.manager@xenproject.org>
> diff --git a/SUPPORT.md b/SUPPORT.md
> index ab02aca5f4..5ee3c8651a 100644
> --- a/SUPPORT.md
> +++ b/SUPPORT.md
> @@ -67,6 +67,7 @@ For the Cortex A57 r0p0 - r1p1, see Errata 832075.
>     Status, Intel VT-d: Supported
>     Status, ARM SMMUv1: Supported, not security supported
>     Status, ARM SMMUv2: Supported, not security supported
> +    Status, ARM SMMUv3: Tech Preview
>     Status, Renesas IPMMU-VMSA: Supported, not security supported
> 
> ### ARM/GICv3 ITS
> diff --git a/xen/drivers/passthrough/Kconfig b/xen/drivers/passthrough/Kconfig
> index 0036007ec4..341ba92b30 100644
> --- a/xen/drivers/passthrough/Kconfig
> +++ b/xen/drivers/passthrough/Kconfig
> @@ -13,6 +13,17 @@ config ARM_SMMU
> 	  Say Y here if your SoC includes an IOMMU device implementing the
> 	  ARM SMMU architecture.
> 
> +config ARM_SMMU_V3
> +	bool "ARM Ltd. System MMU Version 3 (SMMUv3) Support" if EXPERT
> +	depends on ARM_64
> +	---help---
> +	 Support for implementations of the ARM System MMU architecture
> +	 version 3. Driver is in experimental stage and should not be used in
> +	 production.
> +
> +	 Say Y here if your system includes an IOMMU device implementing
> +	 the ARM SMMUv3 architecture.
> +
> config IPMMU_VMSA
> 	bool "Renesas IPMMU-VMSA found in R-Car Gen3 SoCs"
> 	depends on ARM_64
> diff --git a/xen/drivers/passthrough/arm/Makefile b/xen/drivers/passthrough/arm/Makefile
> index fcd918ea3e..c5fb3b58a5 100644
> --- a/xen/drivers/passthrough/arm/Makefile
> +++ b/xen/drivers/passthrough/arm/Makefile
> @@ -1,3 +1,4 @@
> obj-y += iommu.o iommu_helpers.o iommu_fwspec.o
> obj-$(CONFIG_ARM_SMMU) += smmu.o
> obj-$(CONFIG_IPMMU_VMSA) += ipmmu-vmsa.o
> +obj-$(CONFIG_ARM_SMMU_V3) += smmu-v3.o
> diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
> index 2dfadc6a65..dd0540bb5f 100644
> --- a/xen/drivers/passthrough/arm/smmu-v3.c
> +++ b/xen/drivers/passthrough/arm/smmu-v3.c
> @@ -2,37 +2,263 @@
> /*
>  * IOMMU API for ARM architected SMMUv3 implementations.
>  *
> + * Based on Linux's SMMUv3 driver:
> + *    drivers/iommu/arm-smmu-v3.c
> + *    commit: ab435ce49bd1d02e33dfec24f76955dc1196970b
> + * and Xen's SMMU driver:
> + *    xen/drivers/passthrough/arm/smmu.c
> + *
> + * Major differences with regard to Linux driver are as follows:
> + *  1. Driver is currently supported as Tech Preview.
> + *  2. Only Stage-2 translation is supported as compared to the Linux driver
> + *     that supports both Stage-1 and Stage-2 translations.
> + *  3. Use P2M  page table instead of creating one as SMMUv3 has the
> + *     capability to share the page tables with the CPU.
> + *  4. Tasklets are used in place of threaded IRQ's in Linux for event queue
> + *     and priority queue IRQ handling.
> + *  5. Latest version of the Linux SMMUv3 code implements the commands queue
> + *     access functions based on atomic operations implemented in Linux.
> + *     Atomic functions used by the commands queue access functions are not
> + *     implemented in XEN therefore we decided to port the earlier version
> + *     of the code. Atomic operations are introduced to fix the bottleneck of
> + *     the SMMU command queue insertion operation. A new algorithm for
> + *     inserting commands into the queue is introduced, which is
> + *     lock-free on the fast-path.
> + *     Consequence of reverting the patch is that the command queue insertion
> + *     will be slow for large systems as spinlock will be used to serializes
> + *     accesses from all CPUs to the single queue supported by the hardware.
> + *     Once the proper atomic operations will be available in XEN the driver
> + *     can be updated.
> + *  6. Spin lock is used in place of Mutex when attaching a device to the SMMU,
> + *     as there is no blocking locks implementation available in XEN.This might
> + *     introduce latency in XEN. Need to investigate before driver is out for
> + *     Tech Preview.
> + *  7. PCI ATS functionality is not supported, as there is no support available
> + *     in XEN to test the functionality. Code is not tested and compiled. Code
> + *     is guarded by the flag CONFIG_PCI_ATS.
> + *  8. MSI interrupts are not supported as there is no support available
> + *     in XEN to request MSI interrupts. Code is not tested and compiled. Code
> + *     is guarded by the flag CONFIG_MSI.
> + *
> + * Following functionality should be supported before driver is out for tech
> + * preview
> + *
> + *  1. Investigate the timing analysis of using spin lock in place of mutex
> + *     when attaching devices to SMMU.
> + *  2. Merged the latest Linux SMMUv3 driver code once atomic operation is
> + *     available in XEN.
> + *  3. PCI ATS and MSI interrupts should be supported.
> + *  4. Investigate side-effect of using tasklet in place of threaded IRQ and
> + *     fix if any.
> + *
>  * Copyright (C) 2015 ARM Limited
>  *
>  * Author: Will Deacon <will.deacon@arm.com>
>  *
> - * This driver is powered by bad coffee and bombay mix.
> + * Copyright (C) 2020 Arm Ltd
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program.  If not, see <http://www.gnu.org/licenses/>.
> + *
>  */
> 
> -#include <linux/acpi.h>
> -#include <linux/acpi_iort.h>
> -#include <linux/bitfield.h>
> -#include <linux/bitops.h>
> -#include <linux/crash_dump.h>
> -#include <linux/delay.h>
> -#include <linux/dma-iommu.h>
> -#include <linux/err.h>
> -#include <linux/interrupt.h>
> -#include <linux/io-pgtable.h>
> -#include <linux/iommu.h>
> -#include <linux/iopoll.h>
> -#include <linux/module.h>
> -#include <linux/msi.h>
> -#include <linux/of.h>
> -#include <linux/of_address.h>
> -#include <linux/of_iommu.h>
> -#include <linux/of_platform.h>
> -#include <linux/pci.h>
> -#include <linux/pci-ats.h>
> -#include <linux/platform_device.h>
> -
> -#include <linux/amba/bus.h>
> +#include <xen/acpi.h>
> +#include <xen/config.h>
> +#include <xen/delay.h>
> +#include <xen/errno.h>
> +#include <xen/err.h>
> +#include <xen/irq.h>
> +#include <xen/lib.h>
> +#include <xen/list.h>
> +#include <xen/mm.h>
> +#include <xen/rbtree.h>
> +#include <xen/sched.h>
> +#include <xen/sizes.h>
> +#include <xen/vmap.h>
> +#include <asm/atomic.h>
> +#include <asm/device.h>
> +#include <asm/io.h>
> +#include <asm/iommu_fwspec.h>
> +#include <asm/platform.h>
> +
> +
> +#define ARM_SMMU_VTCR_SH_IS		3
> +#define ARM_SMMU_VTCR_RGN_WBWA		1
> +#define ARM_SMMU_VTCR_TG0_4K		0
> +#define ARM_SMMU_VTCR_PS_32_BIT		0x0ULL
> +#define ARM_SMMU_VTCR_PS_36_BIT		0x1ULL
> +#define ARM_SMMU_VTCR_PS_40_BIT		0x2ULL
> +#define ARM_SMMU_VTCR_PS_42_BIT		0x3ULL
> +#define ARM_SMMU_VTCR_PS_44_BIT		0x4ULL
> +#define ARM_SMMU_VTCR_PS_48_BIT		0x5ULL
> +#define ARM_SMMU_VTCR_PS_52_BIT		0x6ULL
> +
> +/* Linux compatibility functions. */
> +typedef paddr_t		dma_addr_t;
> +typedef paddr_t		phys_addr_t;
> +typedef unsigned int		gfp_t;
> +
> +#define platform_device		device
> +
> +#define GFP_KERNEL		0
> +
> +/* Alias to Xen lock functions */
> +#define mutex spinlock
> +#define mutex_init spin_lock_init
> +#define mutex_lock spin_lock
> +#define mutex_unlock spin_unlock
> +
> +/* Device logger functions */
> +#define dev_name(dev)	dt_node_full_name(dev->of_node)
> +#define dev_dbg(dev, fmt, ...)			\
> +	printk(XENLOG_DEBUG "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
> +#define dev_notice(dev, fmt, ...)		\
> +	printk(XENLOG_INFO "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
> +#define dev_warn(dev, fmt, ...)			\
> +	printk(XENLOG_WARNING "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
> +#define dev_err(dev, fmt, ...)			\
> +	printk(XENLOG_ERR "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
> +#define dev_info(dev, fmt, ...)			\
> +	printk(XENLOG_INFO "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
> +#define dev_err_ratelimited(dev, fmt, ...)			\
> +	printk(XENLOG_ERR "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
> +
> +/*
> + * Periodically poll an address and wait between reads in us until a
> + * condition is met or a timeout occurs.
> + *
> + * @return: 0 when cond met, -ETIMEDOUT upon timeout
> + */
> +#define readx_poll_timeout(op, addr, val, cond, sleep_us, timeout_us) \
> +({ \
> +	s_time_t deadline = NOW() + MICROSECS(timeout_us); \
> +	for (;;) { \
> +		(val) = op(addr); \
> +		if (cond) \
> +			break; \
> +		if (NOW() > deadline) { \
> +			(val) = op(addr); \
> +			break; \
> +		} \
> +		udelay(sleep_us); \
> +	} \
> +	(cond) ? 0 : -ETIMEDOUT; \
> +})
> +
> +#define readl_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us)	\
> +	readx_poll_timeout(readl_relaxed, addr, val, cond, delay_us, timeout_us)
> +
> +#define FIELD_PREP(_mask, _val)			\
> +	(((typeof(_mask))(_val) << (ffs64(_mask) - 1)) & (_mask))
> +
> +#define FIELD_GET(_mask, _reg)			\
> +	((typeof(_mask))(((_reg) & (_mask)) >> (ffs64(_mask) - 1)))
> +
> +/*
> + * Helpers for DMA allocation. Just the function name is reused for
> + * porting code, these allocation are not managed allocations
> + */
> +static void *dmam_alloc_coherent(struct device *dev, size_t size,
> +				paddr_t *dma_handle, gfp_t gfp)
> +{
> +	void *vaddr;
> +	unsigned long alignment = size;
> +
> +	/*
> +	 * _xzalloc requires that the (align & (align -1)) = 0. Most of the
> +	 * allocations in SMMU code should send the right value for size. In
> +	 * case this is not true print a warning and align to the size of a
> +	 * (void *)
> +	 */
> +	if (size & (size - 1)) {
> +		printk(XENLOG_WARNING "SMMUv3: Fixing alignment for the DMA buffer\n");
> +		alignment = sizeof(void *);
> +	}
> +
> +	vaddr = _xzalloc(size, alignment);
> +	if (!vaddr) {
> +		printk(XENLOG_ERR "SMMUv3: DMA allocation failed\n");
> +		return NULL;
> +	}
> +
> +	*dma_handle = virt_to_maddr(vaddr);
> +
> +	return vaddr;
> +}
> +
> +
> +/* Xen specific code. */
> +struct iommu_domain {
> +	/* Runtime SMMU configuration for this iommu_domain */
> +	atomic_t		ref;
> +	/*
> +	 * Used to link iommu_domain contexts for a same domain.
> +	 * There is at least one per-SMMU to used by the domain.
> +	 */
> +	struct list_head		list;
> +};
> +
> +/* Describes information required for a Xen domain */
> +struct arm_smmu_xen_domain {
> +	spinlock_t		lock;
> +
> +	/* List of iommu domains associated to this domain */
> +	struct list_head	contexts;
> +};
> +
> +
> +/* Keep a list of devices associated with this driver */
> +static DEFINE_SPINLOCK(arm_smmu_devices_lock);
> +static LIST_HEAD(arm_smmu_devices);
> +
> +static inline void *dev_iommu_priv_get(struct device *dev)
> +{
> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> +
> +	return fwspec && fwspec->iommu_priv ? fwspec->iommu_priv : NULL;
> +}
> +
> +static inline void dev_iommu_priv_set(struct device *dev, void *priv)
> +{
> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> +
> +	fwspec->iommu_priv = priv;
> +}
> +
> +static int platform_get_irq_byname_optional(struct device *dev,
> +				const char *name)
> +{
> +	int index, ret;
> +	struct dt_device_node *np  = dev_to_dt(dev);
> +
> +	if (unlikely(!name))
> +		return -EINVAL;
> +
> +	index = dt_property_match_string(np, "interrupt-names", name);
> +	if (index < 0) {
> +		dev_info(dev, "IRQ %s not found\n", name);
> +		return index;
> +	}
> +
> +	ret = platform_get_irq(np, index);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to get irq index %d\n", index);
> +		return -ENODEV;
> +	}
> +
> +	return ret;
> +}
> 
> +/* Start of Linux SMMUv3 code */
> /* MMIO registers */
> #define ARM_SMMU_IDR0			0x0
> #define IDR0_ST_LVL			GENMASK(28, 27)
> @@ -402,6 +628,7 @@ enum pri_resp {
> 	PRI_RESP_SUCC = 2,
> };
> 
> +#ifdef CONFIG_MSI
> enum arm_smmu_msi_index {
> 	EVTQ_MSI_INDEX,
> 	GERROR_MSI_INDEX,
> @@ -426,6 +653,7 @@ static phys_addr_t arm_smmu_msi_cfg[ARM_SMMU_MAX_MSIS][3] = {
> 		ARM_SMMU_PRIQ_IRQ_CFG2,
> 	},
> };
> +#endif /* CONFIG_MSI */
> 
> struct arm_smmu_cmdq_ent {
> 	/* Common fields */
> @@ -613,8 +841,13 @@ struct arm_smmu_device {
> 		u64			padding;
> 	};
> 
> -	/* IOMMU core code handle */
> -	struct iommu_device		iommu;
> +	/* Need to keep a list of SMMU devices */
> +	struct list_head		devices;
> +
> +	/* Tasklets for handling evts/faults and pci page request IRQs*/
> +	struct tasklet		evtq_irq_tasklet;
> +	struct tasklet		priq_irq_tasklet;
> +	struct tasklet		combined_irq_tasklet;
> };
> 
> /* SMMU private data for each master */
> @@ -646,6 +879,9 @@ struct arm_smmu_domain {
> 	enum arm_smmu_domain_stage	stage;
> 	struct arm_smmu_s2_cfg	s2_cfg;
> 
> +	/* Xen domain associated with this SMMU domain */
> +	struct domain		*d;
> +
> 	struct iommu_domain		domain;
> 
> 	struct list_head		devices;
> @@ -984,6 +1220,7 @@ static void arm_smmu_cmdq_issue_cmd(struct arm_smmu_device *smmu,
> 	spin_unlock_irqrestore(&smmu->cmdq.lock, flags);
> }
> 
> +#ifdef CONFIG_MSI
> /*
>  * The difference between val and sync_idx is bounded by the maximum size of
>  * a queue at 2^20 entries, so 32 bits is plenty for wrap-safe arithmetic.
> @@ -1027,6 +1264,13 @@ static int __arm_smmu_cmdq_issue_sync_msi(struct arm_smmu_device *smmu)
> 
> 	return __arm_smmu_sync_poll_msi(smmu, ent.sync.msidata);
> }
> +#else
> +static inline int __arm_smmu_cmdq_issue_sync_msi(struct arm_smmu_device *smmu)
> +{
> +	return 0;
> +}
> +#endif /* CONFIG_MSI */
> +
> 
> static int __arm_smmu_cmdq_issue_sync(struct arm_smmu_device *smmu)
> {
> @@ -1069,7 +1313,7 @@ arm_smmu_write_strtab_l1_desc(__le64 *dst, struct arm_smmu_strtab_l1_desc *desc)
> 	val |= desc->l2ptr_dma & STRTAB_L1_DESC_L2PTR_MASK;
> 
> 	/* See comment in arm_smmu_write_ctx_desc() */
> -	WRITE_ONCE(*dst, cpu_to_le64(val));
> +	write_atomic(dst, cpu_to_le64(val));
> }
> 
> static void arm_smmu_sync_ste_for_sid(struct arm_smmu_device *smmu, u32 sid)
> @@ -1184,7 +1428,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
> 						 STRTAB_STE_1_EATS_TRANS));
> 
> 	arm_smmu_sync_ste_for_sid(smmu, sid);
> -	WRITE_ONCE(dst[0], cpu_to_le64(val));
> +	write_atomic(&dst[0], cpu_to_le64(val));
> 	arm_smmu_sync_ste_for_sid(smmu, sid);
> 
> 	/* It's likely that we'll want to use the new STE soon */
> @@ -1231,7 +1475,7 @@ static int arm_smmu_init_l2_strtab(struct arm_smmu_device *smmu, u32 sid)
> }
> 
> /* IRQ and event handlers */
> -static irqreturn_t arm_smmu_evtq_thread(int irq, void *dev)
> +static void arm_smmu_evtq_tasklet(void *dev)
> {
> 	int i;
> 	struct arm_smmu_device *smmu = dev;
> @@ -1261,7 +1505,6 @@ static irqreturn_t arm_smmu_evtq_thread(int irq, void *dev)
> 	/* Sync our overflow flag, as we believe we're up to speed */
> 	llq->cons = Q_OVF(llq->prod) | Q_WRP(llq, llq->cons) |
> 		    Q_IDX(llq, llq->cons);
> -	return IRQ_HANDLED;
> }
> 
> static void arm_smmu_handle_ppr(struct arm_smmu_device *smmu, u64 *evt)
> @@ -1302,7 +1545,7 @@ static void arm_smmu_handle_ppr(struct arm_smmu_device *smmu, u64 *evt)
> 	}
> }
> 
> -static irqreturn_t arm_smmu_priq_thread(int irq, void *dev)
> +static void arm_smmu_priq_tasklet(void *dev)
> {
> 	struct arm_smmu_device *smmu = dev;
> 	struct arm_smmu_queue *q = &smmu->priq.q;
> @@ -1321,12 +1564,12 @@ static irqreturn_t arm_smmu_priq_thread(int irq, void *dev)
> 	llq->cons = Q_OVF(llq->prod) | Q_WRP(llq, llq->cons) |
> 		      Q_IDX(llq, llq->cons);
> 	queue_sync_cons_out(q);
> -	return IRQ_HANDLED;
> }
> 
> static int arm_smmu_device_disable(struct arm_smmu_device *smmu);
> 
> -static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
> +static void arm_smmu_gerror_handler(int irq, void *dev,
> +				struct cpu_user_regs *regs)
> {
> 	u32 gerror, gerrorn, active;
> 	struct arm_smmu_device *smmu = dev;
> @@ -1336,7 +1579,7 @@ static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
> 
> 	active = gerror ^ gerrorn;
> 	if (!(active & GERROR_ERR_MASK))
> -		return IRQ_NONE; /* No errors pending */
> +		return; /* No errors pending */
> 
> 	dev_warn(smmu->dev,
> 		 "unexpected global error reported (0x%08x), this could be serious\n",
> @@ -1369,26 +1612,44 @@ static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
> 		arm_smmu_cmdq_skip_err(smmu);
> 
> 	writel(gerror, smmu->base + ARM_SMMU_GERRORN);
> -	return IRQ_HANDLED;
> }
> 
> -static irqreturn_t arm_smmu_combined_irq_thread(int irq, void *dev)
> +static void arm_smmu_combined_irq_handler(int irq, void *dev,
> +				struct cpu_user_regs *regs)
> {
> 	struct arm_smmu_device *smmu = dev;
> 
> -	arm_smmu_evtq_thread(irq, dev);
> +	arm_smmu_gerror_handler(irq, dev, regs);
> +
> +	tasklet_schedule(&(smmu->combined_irq_tasklet));
> +}
> +
> +static void arm_smmu_combined_irq_tasklet(void *dev)
> +{
> +	struct arm_smmu_device *smmu = dev;
> +
> +	arm_smmu_evtq_tasklet(dev);
> 	if (smmu->features & ARM_SMMU_FEAT_PRI)
> -		arm_smmu_priq_thread(irq, dev);
> +		arm_smmu_priq_tasklet(dev);
> +}
> +
> +static void arm_smmu_evtq_irq_tasklet(int irq, void *dev,
> +				struct cpu_user_regs *regs)
> +{
> +	struct arm_smmu_device *smmu = dev;
> 
> -	return IRQ_HANDLED;
> +	tasklet_schedule(&(smmu->evtq_irq_tasklet));
> }
> 
> -static irqreturn_t arm_smmu_combined_irq_handler(int irq, void *dev)
> +static void arm_smmu_priq_irq_tasklet(int irq, void *dev,
> +				struct cpu_user_regs *regs)
> {
> -	arm_smmu_gerror_handler(irq, dev);
> -	return IRQ_WAKE_THREAD;
> +	struct arm_smmu_device *smmu = dev;
> +
> +	tasklet_schedule(&(smmu->priq_irq_tasklet));
> }
> 
> +#ifdef CONFIG_PCI_ATS
> static void
> arm_smmu_atc_inv_to_cmd(int ssid, unsigned long iova, size_t size,
> 			struct arm_smmu_cmdq_ent *cmd)
> @@ -1495,6 +1756,7 @@ static int arm_smmu_atc_inv_domain(struct arm_smmu_domain *smmu_domain,
> 
> 	return ret ? -ETIMEDOUT : 0;
> }
> +#endif /* CONFIG_PCI_ATS */
> 
> static void arm_smmu_tlb_inv_context(void *cookie)
> {
> @@ -1525,7 +1787,7 @@ static struct iommu_domain *arm_smmu_domain_alloc(void)
> 	 * We can't really do anything meaningful until we've added a
> 	 * master.
> 	 */
> -	smmu_domain = kzalloc(sizeof(*smmu_domain), GFP_KERNEL);
> +	smmu_domain = xzalloc(struct arm_smmu_domain);
> 	if (!smmu_domain)
> 		return NULL;
> 
> @@ -1563,7 +1825,7 @@ static void arm_smmu_domain_free(struct iommu_domain *domain)
> 	if (cfg->vmid)
> 		arm_smmu_bitmap_free(smmu->vmid_map, cfg->vmid);
> 
> -	kfree(smmu_domain);
> +	xfree(smmu_domain);
> }
> 
> 
> @@ -1576,6 +1838,44 @@ static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
> 	struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
> 	typeof(&arm_lpae_s2_cfg.vtcr) vtcr = &arm_lpae_s2_cfg.vtcr;
> 
> +	vtcr->sh = ARM_SMMU_VTCR_SH_IS;
> +	vtcr->irgn = ARM_SMMU_VTCR_RGN_WBWA;
> +	vtcr->orgn = ARM_SMMU_VTCR_RGN_WBWA;
> +
> +	BUILD_BUG_ON(PAGE_SIZE != SZ_4K);
> +	vtcr->tg = ARM_SMMU_VTCR_TG0_4K;
> +
> +	switch (smmu->oas) {
> +	case 32:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_32_BIT;
> +		break;
> +	case 36:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_36_BIT;
> +		break;
> +	case 40:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_40_BIT;
> +		break;
> +	case 42:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_42_BIT;
> +		break;
> +	case 44:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_44_BIT;
> +		break;
> +	case 48:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_48_BIT;
> +		break;
> +	case 52:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_52_BIT;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	vtcr->tsz = 64 - p2m_ipa_bits;
> +	vtcr->sl = 2 - P2M_ROOT_LEVEL;
> +
> +	arm_lpae_s2_cfg.vttbr  = page_to_maddr(smmu_domain->d->arch.p2m.root);
> +
> 	vmid = arm_smmu_bitmap_alloc(smmu->vmid_map, smmu->vmid_bits);
> 	if (vmid < 0)
> 		return vmid;
> @@ -1589,6 +1889,11 @@ static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
> 			  FIELD_PREP(STRTAB_STE_2_VTCR_S2SH0, vtcr->sh) |
> 			  FIELD_PREP(STRTAB_STE_2_VTCR_S2TG, vtcr->tg) |
> 			  FIELD_PREP(STRTAB_STE_2_VTCR_S2PS, vtcr->ps);
> +
> +	printk(XENLOG_DEBUG
> +		   "SMMUv3: d%u: vmid 0x%x vtcr 0x%"PRIpaddr" p2maddr 0x%"PRIpaddr"\n",
> +		   smmu_domain->d->domain_id, cfg->vmid, cfg->vtcr, cfg->vttbr);
> +
> 	return 0;
> }
> 
> @@ -1650,6 +1955,7 @@ static void arm_smmu_install_ste_for_dev(struct arm_smmu_master *master)
> 	}
> }
> 
> +#ifdef CONFIG_PCI_ATS
> static bool arm_smmu_ats_supported(struct arm_smmu_master *master)
> {
> 	struct device *dev = master->dev;
> @@ -1748,6 +2054,23 @@ static void arm_smmu_disable_pasid(struct arm_smmu_master *master)
> 
> 	pci_disable_pasid(pdev);
> }
> +#else
> +static inline bool arm_smmu_ats_supported(struct arm_smmu_master *master)
> +{
> +	return false;
> +}
> +
> +static inline void arm_smmu_enable_ats(struct arm_smmu_master *master) { }
> +
> +static inline void arm_smmu_disable_ats(struct arm_smmu_master *master) { }
> +
> +static inline int arm_smmu_enable_pasid(struct arm_smmu_master *master)
> +{
> +	return 0;
> +}
> +
> +static inline void arm_smmu_disable_pasid(struct arm_smmu_master *master) { }
> +#endif /* CONFIG_PCI_ATS */
> 
> static void arm_smmu_detach_dev(struct arm_smmu_master *master)
> {
> @@ -1830,8 +2153,10 @@ static bool arm_smmu_sid_in_range(struct arm_smmu_device *smmu, u32 sid)
> 
> 	return sid < limit;
> }
> +/* Forward declaration */
> +static struct arm_smmu_device *arm_smmu_get_by_dev(struct device *dev);
> 
> -static struct iommu_device *arm_smmu_probe_device(struct device *dev)
> +static int arm_smmu_add_device(u8 devfn, struct device *dev)
> {
> 	int i, ret;
> 	struct arm_smmu_device *smmu;
> @@ -1839,14 +2164,15 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
> 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> 
> 	if (!fwspec)
> -		return ERR_PTR(-ENODEV);
> +		return -ENODEV;
> 
> -	if (WARN_ON_ONCE(dev_iommu_priv_get(dev)))
> -		return ERR_PTR(-EBUSY);
> +	smmu = arm_smmu_get_by_dev(fwspec->iommu_dev);
> +	if (!smmu)
> +		return -ENODEV;
> 
> -	master = kzalloc(sizeof(*master), GFP_KERNEL);
> +	master = xzalloc(struct arm_smmu_master);
> 	if (!master)
> -		return ERR_PTR(-ENOMEM);
> +		return -ENOMEM;
> 
> 	master->dev = dev;
> 	master->smmu = smmu;
> @@ -1881,17 +2207,36 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
> 	 */
> 	arm_smmu_enable_pasid(master);
> 
> -	return &smmu->iommu;
> +	return 0;
> 
> err_free_master:
> -	kfree(master);
> +	xfree(master);
> 	dev_iommu_priv_set(dev, NULL);
> -	return ERR_PTR(ret);
> +	return ret;
> }
> 
> -static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args)
> +static int arm_smmu_dt_xlate(struct device *dev,
> +				const struct dt_phandle_args *args)
> {
> -	return iommu_fwspec_add_ids(dev, args->args, 1);
> +	int ret;
> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> +
> +	ret = iommu_fwspec_add_ids(dev, args->args, 1);
> +	if (ret)
> +		return ret;
> +
> +	if (dt_device_is_protected(dev_to_dt(dev))) {
> +		dev_err(dev, "Already added to SMMUv3\n");
> +		return -EEXIST;
> +	}
> +
> +	/* Let Xen know that the master device is protected by an IOMMU. */
> +	dt_device_set_protected(dev_to_dt(dev));
> +
> +	dev_info(dev, "Added master device (SMMUv3 %s StreamIds %u)\n",
> +			dev_name(fwspec->iommu_dev), fwspec->num_ids);
> +
> +	return 0;
> }
> 
> /* Probing and initialisation functions */
> @@ -1972,7 +2317,7 @@ static int arm_smmu_init_l1_strtab(struct arm_smmu_device *smmu)
> 	size_t size = sizeof(*cfg->l1_desc) * cfg->num_l1_ents;
> 	void *strtab = smmu->strtab_cfg.strtab;
> 
> -	cfg->l1_desc = devm_kzalloc(smmu->dev, size, GFP_KERNEL);
> +	cfg->l1_desc = _xzalloc(size, sizeof(void *));
> 	if (!cfg->l1_desc) {
> 		dev_err(smmu->dev, "failed to allocate l1 stream table desc\n");
> 		return -ENOMEM;
> @@ -2118,6 +2463,7 @@ static int arm_smmu_update_gbpa(struct arm_smmu_device *smmu, u32 set, u32 clr)
> 	return ret;
> }
> 
> +#ifdef CONFIG_MSI
> static void arm_smmu_free_msis(void *data)
> {
> 	struct device *dev = data;
> @@ -2188,8 +2534,35 @@ static void arm_smmu_setup_msis(struct arm_smmu_device *smmu)
> 	/* Add callback to free MSIs on teardown */
> 	devm_add_action(dev, arm_smmu_free_msis, dev);
> }
> +#else
> +static inline void arm_smmu_setup_msis(struct arm_smmu_device *smmu) { }
> +#endif /* CONFIG_MSI */
> 
> -static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
> +static void arm_smmu_free_irqs(struct arm_smmu_device *smmu)
> +{
> +	int irq;
> +
> +	irq = smmu->combined_irq;
> +	if (irq)
> +		release_irq(irq, smmu);
> +	else {
> +		irq = smmu->evtq.q.irq;
> +		if (irq)
> +			release_irq(irq, smmu);
> +
> +		irq = smmu->gerr_irq;
> +		if (irq)
> +			release_irq(irq, smmu);
> +
> +		if (smmu->features & ARM_SMMU_FEAT_PRI) {
> +			irq = smmu->priq.q.irq;
> +			if (irq)
> +				release_irq(irq, smmu);
> +		}
> +	}
> +}
> +
> +static int arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
> {
> 	int irq, ret;
> 
> @@ -2198,22 +2571,24 @@ static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
> 	/* Request interrupt lines */
> 	irq = smmu->evtq.q.irq;
> 	if (irq) {
> -		ret = devm_request_threaded_irq(smmu->dev, irq, NULL,
> -						arm_smmu_evtq_thread,
> -						IRQF_ONESHOT,
> +		ret = request_irq(irq, 0, arm_smmu_evtq_irq_tasklet,
> 						"arm-smmu-v3-evtq", smmu);
> -		if (ret < 0)
> +		if (ret < 0) {
> 			dev_warn(smmu->dev, "failed to enable evtq irq\n");
> +			return ret;
> +		}
> 	} else {
> 		dev_warn(smmu->dev, "no evtq irq - events will not be reported!\n");
> 	}
> 
> 	irq = smmu->gerr_irq;
> 	if (irq) {
> -		ret = devm_request_irq(smmu->dev, irq, arm_smmu_gerror_handler,
> -				       0, "arm-smmu-v3-gerror", smmu);
> -		if (ret < 0)
> +		ret = request_irq(irq, 0, arm_smmu_gerror_handler,
> +						"arm-smmu-v3-gerror", smmu);
> +		if (ret < 0) {
> 			dev_warn(smmu->dev, "failed to enable gerror irq\n");
> +			goto err_free_evtq_irq;
> +		}
> 	} else {
> 		dev_warn(smmu->dev, "no gerr irq - errors will not be reported!\n");
> 	}
> @@ -2221,18 +2596,30 @@ static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
> 	if (smmu->features & ARM_SMMU_FEAT_PRI) {
> 		irq = smmu->priq.q.irq;
> 		if (irq) {
> -			ret = devm_request_threaded_irq(smmu->dev, irq, NULL,
> -							arm_smmu_priq_thread,
> -							IRQF_ONESHOT,
> -							"arm-smmu-v3-priq",
> -							smmu);
> -			if (ret < 0)
> +			ret = request_irq(irq, 0, arm_smmu_priq_irq_tasklet,
> +							"arm-smmu-v3-priq", smmu);
> +			if (ret < 0) {
> 				dev_warn(smmu->dev,
> 					 "failed to enable priq irq\n");
> +				goto err_free_gerr_irq;
> +			}
> 		} else {
> 			dev_warn(smmu->dev, "no priq irq - PRI will be broken\n");
> 		}
> 	}
> +
> +	return 0;
> +
> +err_free_gerr_irq:
> +	irq = smmu->gerr_irq;
> +	if (irq)
> +		release_irq(irq, smmu);
> +err_free_evtq_irq:
> +	irq = smmu->evtq.q.irq;
> +	if (irq)
> +		release_irq(irq, smmu);
> +
> +	return ret;
> }
> 
> static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
> @@ -2254,15 +2641,19 @@ static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
> 		 * Cavium ThunderX2 implementation doesn't support unique irq
> 		 * lines. Use a single irq line for all the SMMUv3 interrupts.
> 		 */
> -		ret = devm_request_threaded_irq(smmu->dev, irq,
> -					arm_smmu_combined_irq_handler,
> -					arm_smmu_combined_irq_thread,
> -					IRQF_ONESHOT,
> -					"arm-smmu-v3-combined-irq", smmu);
> -		if (ret < 0)
> +		ret = request_irq(irq, 0, arm_smmu_combined_irq_handler,
> +						"arm-smmu-v3-combined-irq", smmu);
> +		if (ret < 0) {
> 			dev_warn(smmu->dev, "failed to enable combined irq\n");
> -	} else
> -		arm_smmu_setup_unique_irqs(smmu);
> +			return ret;
> +		}
> +	} else {
> +		ret = arm_smmu_setup_unique_irqs(smmu);
> +		if (ret) {
> +			dev_warn(smmu->dev, "failed to setup unique irqs\n");
> +			return ret;
> +		}
> +	}
> 
> 	if (smmu->features & ARM_SMMU_FEAT_PRI)
> 		irqen_flags |= IRQ_CTRL_PRIQ_IRQEN;
> @@ -2270,10 +2661,16 @@ static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
> 	/* Enable interrupt generation on the SMMU */
> 	ret = arm_smmu_write_reg_sync(smmu, irqen_flags,
> 				      ARM_SMMU_IRQ_CTRL, ARM_SMMU_IRQ_CTRLACK);
> -	if (ret)
> +	if (ret) {
> 		dev_warn(smmu->dev, "failed to enable irqs\n");
> +		goto err_free_irqs;
> +	}
> 
> 	return 0;
> +
> +err_free_irqs:
> +	arm_smmu_free_irqs(smmu);
> +	return ret;
> }
> 
> static int arm_smmu_device_disable(struct arm_smmu_device *smmu)
> @@ -2287,7 +2684,7 @@ static int arm_smmu_device_disable(struct arm_smmu_device *smmu)
> 	return ret;
> }
> 
> -static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
> +static int arm_smmu_device_reset(struct arm_smmu_device *smmu)
> {
> 	int ret;
> 	u32 reg, enables;
> @@ -2297,7 +2694,7 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
> 	reg = readl_relaxed(smmu->base + ARM_SMMU_CR0);
> 	if (reg & CR0_SMMUEN) {
> 		dev_warn(smmu->dev, "SMMU currently enabled! Resetting...\n");
> -		WARN_ON(is_kdump_kernel() && !disable_bypass);
> +		WARN_ON(!disable_bypass);
> 		arm_smmu_update_gbpa(smmu, GBPA_ABORT, 0);
> 	}
> 
> @@ -2401,25 +2798,32 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
> 		return ret;
> 	}
> 
> -	if (is_kdump_kernel())
> -		enables &= ~(CR0_EVTQEN | CR0_PRIQEN);
> +	/* Initialize tasklets for threaded IRQs*/
> +	tasklet_init(&smmu->evtq_irq_tasklet, arm_smmu_evtq_tasklet, smmu);
> +	tasklet_init(&smmu->priq_irq_tasklet, arm_smmu_priq_tasklet, smmu);
> +	tasklet_init(&smmu->combined_irq_tasklet, arm_smmu_combined_irq_tasklet,
> +				 smmu);
> 
> 	/* Enable the SMMU interface, or ensure bypass */
> -	if (!bypass || disable_bypass) {
> +	if (disable_bypass) {
> 		enables |= CR0_SMMUEN;
> 	} else {
> 		ret = arm_smmu_update_gbpa(smmu, 0, GBPA_ABORT);
> 		if (ret)
> -			return ret;
> +			goto err_free_irqs;
> 	}
> 	ret = arm_smmu_write_reg_sync(smmu, enables, ARM_SMMU_CR0,
> 				      ARM_SMMU_CR0ACK);
> 	if (ret) {
> 		dev_err(smmu->dev, "failed to enable SMMU interface\n");
> -		return ret;
> +		goto err_free_irqs;
> 	}
> 
> 	return 0;
> +
> +err_free_irqs:
> +	arm_smmu_free_irqs(smmu);
> +	return ret;
> }
> 
> static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> @@ -2470,8 +2874,10 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> 	if (reg & IDR0_SEV)
> 		smmu->features |= ARM_SMMU_FEAT_SEV;
> 
> +#ifdef CONFIG_MSI
> 	if (reg & IDR0_MSI)
> 		smmu->features |= ARM_SMMU_FEAT_MSI;
> +#endif
> 
> 	if (reg & IDR0_HYP)
> 		smmu->features |= ARM_SMMU_FEAT_HYP;
> @@ -2496,7 +2902,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> 		smmu->features |= ARM_SMMU_FEAT_TRANS_S2;
> 
> 	if (!(reg & IDR0_S2P)) {
> -		dev_err(smmu->dev, "no translation support!\n");
> +		dev_err(smmu->dev, "no stage-2 translation support!\n");
> 		return -ENXIO;
> 	}
> 
> @@ -2593,8 +2999,12 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> 		smmu->oas = 48;
> 	}
> 
> +	smmu->oas = min_t(unsigned long, PADDR_BITS, smmu->oas);
> 	smmu->ias = max(smmu->ias, smmu->oas);
> 
> +	/* Xen: Set maximum Stage-2 input size supported by the SMMU. */
> +	p2m_restrict_ipa_bits(smmu->ias);
> +
> 	dev_info(smmu->dev, "ias %lu-bit, oas %lu-bit (features 0x%08x)\n",
> 		 smmu->ias, smmu->oas, smmu->features);
> 	return 0;
> @@ -2645,7 +3055,7 @@ static inline int arm_smmu_device_acpi_probe(struct platform_device *pdev,
> static int arm_smmu_device_dt_probe(struct platform_device *pdev,
> 				    struct arm_smmu_device *smmu)
> {
> -	struct device *dev = &pdev->dev;
> +	struct device *dev = pdev;
> 	u32 cells;
> 	int ret = -EINVAL;
> 
> @@ -2658,7 +3068,7 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev,
> 
> 	parse_driver_options(smmu);
> 
> -	if (of_dma_is_coherent(dev->of_node))
> +	if (dt_get_property(dev->of_node, "dma-coherent", NULL))
> 		smmu->features |= ARM_SMMU_FEAT_COHERENCY;
> 
> 	return ret;
> @@ -2672,66 +3082,76 @@ static unsigned long arm_smmu_resource_size(struct arm_smmu_device *smmu)
> 		return SZ_128K;
> }
> 
> -static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
> -				      resource_size_t size)
> +
> +static void arm_smmu_free_structures(struct arm_smmu_device *smmu)
> {
> -	struct resource res = {
> -		.flags = IORESOURCE_MEM,
> -		.start = start,
> -		.end = start + size - 1,
> -	};
> +	if (smmu->cmdq.q.base)
> +		xfree(smmu->cmdq.q.base);
> +
> +	if (smmu->evtq.q.base)
> +		xfree(smmu->evtq.q.base);
> 
> -	return devm_ioremap_resource(dev, &res);
> +	if (smmu->priq.q.base)
> +		xfree(smmu->priq.q.base);
> +
> +	if (smmu->strtab_cfg.strtab)
> +		xfree(smmu->strtab_cfg.strtab);
> +
> +	if (smmu->strtab_cfg.l1_desc)
> +		xfree(smmu->strtab_cfg.l1_desc);
> }
> 
> static int arm_smmu_device_probe(struct platform_device *pdev)
> {
> 	int irq, ret;
> -	struct resource *res;
> -	resource_size_t ioaddr;
> +	paddr_t ioaddr, iosize;
> 	struct arm_smmu_device *smmu;
> -	struct device *dev = &pdev->dev;
> -	bool bypass;
> 
> -	smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
> +	smmu = xzalloc(struct arm_smmu_device);
> 	if (!smmu) {
> -		dev_err(dev, "failed to allocate arm_smmu_device\n");
> +		dev_err(pdev, "failed to allocate arm_smmu_device\n");
> 		return -ENOMEM;
> 	}
> -	smmu->dev = dev;
> +	smmu->dev = pdev;
> 
> -	if (dev->of_node) {
> +	if (pdev->of_node) {
> 		ret = arm_smmu_device_dt_probe(pdev, smmu);
> +		if (ret)
> +			goto out_free_smmu;
> 	} else {
> 		ret = arm_smmu_device_acpi_probe(pdev, smmu);
> 		if (ret == -ENODEV)
> -			return ret;
> +			goto out_free_smmu;
> 	}
> 
> -	/* Set bypass mode according to firmware probing result */
> -	bypass = !!ret;
> -
> 	/* Base address */
> -	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> -	if (resource_size(res) < arm_smmu_resource_size(smmu)) {
> -		dev_err(dev, "MMIO region too small (%pr)\n", res);
> -		return -EINVAL;
> +	ret = dt_device_get_address(dev_to_dt(pdev), 0, &ioaddr, &iosize);
> +	if (ret)
> +		goto out_free_smmu;
> +
> +	if (iosize < arm_smmu_resource_size(smmu)) {
> +		dev_err(pdev, "MMIO region too small (%lx)\n", iosize);
> +		ret = -EINVAL;
> +		goto out_free_smmu;
> 	}
> -	ioaddr = res->start;
> 
> 	/*
> 	 * Don't map the IMPLEMENTATION DEFINED regions, since they may contain
> -	 * the PMCG registers which are reserved by the PMU driver.
> +	 * the PMCG registers which are optional and currently not supported.
> 	 */
> -	smmu->base = arm_smmu_ioremap(dev, ioaddr, ARM_SMMU_REG_SZ);
> -	if (IS_ERR(smmu->base))
> -		return PTR_ERR(smmu->base);
> +	smmu->base = ioremap_nocache(ioaddr, ARM_SMMU_REG_SZ);
> +	if (IS_ERR(smmu->base)) {
> +		ret = PTR_ERR(smmu->base);
> +		goto out_free_smmu;
> +	}
> 
> -	if (arm_smmu_resource_size(smmu) > SZ_64K) {
> -		smmu->page1 = arm_smmu_ioremap(dev, ioaddr + SZ_64K,
> +	if (iosize > SZ_64K) {
> +		smmu->page1 = ioremap_nocache(ioaddr + SZ_64K,
> 					       ARM_SMMU_REG_SZ);
> -		if (IS_ERR(smmu->page1))
> -			return PTR_ERR(smmu->page1);
> +		if (IS_ERR(smmu->page1)) {
> +			ret = PTR_ERR(smmu->page1);
> +			goto out_free;
> +		}
> 	} else {
> 		smmu->page1 = smmu->base;
> 	}
> @@ -2756,23 +3176,286 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
> 	}
> 	/* Probe the h/w */
> 	ret = arm_smmu_device_hw_probe(smmu);
> -	if (ret)
> -		return ret;
> +	if (ret) {
> +		ret = -ENODEV;
> +		goto out_free;
> +	}
> 
> 	/* Initialise in-memory data structures */
> 	ret = arm_smmu_init_structures(smmu);
> 	if (ret)
> -		return ret;
> +		goto out_free;
> 
> 	/* Reset the device */
> -	ret = arm_smmu_device_reset(smmu, bypass);
> +	ret = arm_smmu_device_reset(smmu);
> 	if (ret)
> -		return ret;
> +		goto out_free;
> +
> +	/*
> +	 * Keep a list of all probed devices. This will be used to query
> +	 * the smmu devices based on the fwnode.
> +	 */
> +	INIT_LIST_HEAD(&smmu->devices);
> +
> +	spin_lock(&arm_smmu_devices_lock);
> +	list_add(&smmu->devices, &arm_smmu_devices);
> +	spin_unlock(&arm_smmu_devices_lock);
> 
> 	return 0;
> +
> +
> +out_free:
> +	arm_smmu_free_structures(smmu);
> +	if (smmu->page1)
> +		iounmap(smmu->page1);
> +	if (smmu->base)
> +		iounmap(smmu->base);
> +
> +out_free_smmu:
> +	xfree(smmu);
> +
> +	return ret;
> }
> 
> -static const struct of_device_id arm_smmu_of_match[] = {
> +static const struct dt_device_match arm_smmu_of_match[] = {
> 	{ .compatible = "arm,smmu-v3", },
> 	{ },
> };
> +
> +/* Start of Xen specific code. */
> +static int __must_check arm_smmu_iotlb_flush_all(struct domain *d)
> +{
> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
> +	struct iommu_domain *io_domain;
> +
> +	spin_lock(&xen_domain->lock);
> +
> +	list_for_each_entry(io_domain, &xen_domain->contexts, list) {
> +		/*
> +		 * Only invalidate the context when SMMU is present.
> +		 * This is because the context initialization is delayed
> +		 * until a master has been added.
> +		 */
> +		if (unlikely(!ACCESS_ONCE(to_smmu_domain(io_domain)->smmu)))
> +			continue;
> +
> +		arm_smmu_tlb_inv_context(to_smmu_domain(io_domain));
> +	}
> +
> +	spin_unlock(&xen_domain->lock);
> +
> +	return 0;
> +}
> +
> +static int __must_check arm_smmu_iotlb_flush(struct domain *d, dfn_t dfn,
> +				unsigned long page_count, unsigned int flush_flags)
> +{
> +	return arm_smmu_iotlb_flush_all(d);
> +}
> +
> +static struct arm_smmu_device *arm_smmu_get_by_dev(struct device *dev)
> +{
> +	struct arm_smmu_device *smmu = NULL;
> +
> +	spin_lock(&arm_smmu_devices_lock);
> +
> +	list_for_each_entry(smmu, &arm_smmu_devices, devices) {
> +		if (smmu->dev  == dev) {
> +			spin_unlock(&arm_smmu_devices_lock);
> +			return smmu;
> +		}
> +	}
> +
> +	spin_unlock(&arm_smmu_devices_lock);
> +
> +	return NULL;
> +}
> +
> +static struct iommu_domain *arm_smmu_get_domain(struct domain *d,
> +				struct device *dev)
> +{
> +	struct iommu_domain *io_domain;
> +	struct arm_smmu_domain *smmu_domain;
> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
> +	struct arm_smmu_device *smmu = arm_smmu_get_by_dev(fwspec->iommu_dev);
> +
> +	if (!smmu)
> +		return NULL;
> +
> +	/*
> +	 * Loop through the &xen_domain->contexts to locate a context
> +	 * assigned to this SMMU
> +	 */
> +	list_for_each_entry(io_domain, &xen_domain->contexts, list) {
> +		smmu_domain = to_smmu_domain(io_domain);
> +		if (smmu_domain->smmu == smmu)
> +			return io_domain;
> +	}
> +	return NULL;
> +}
> +
> +static void arm_smmu_destroy_iommu_domain(struct iommu_domain *io_domain)
> +{
> +	list_del(&io_domain->list);
> +	arm_smmu_domain_free(io_domain);
> +}
> +
> +static int arm_smmu_assign_dev(struct domain *d, u8 devfn,
> +		struct device *dev, u32 flag)
> +{
> +	int ret = 0;
> +	struct iommu_domain *io_domain;
> +	struct arm_smmu_domain *smmu_domain;
> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
> +
> +	spin_lock(&xen_domain->lock);
> +
> +	/*
> +	 * Check to see if an iommu_domain already exists for this xen domain
> +	 * under the same SMMU
> +	 */
> +	io_domain = arm_smmu_get_domain(d, dev);
> +	if (!io_domain) {
> +		io_domain = arm_smmu_domain_alloc();
> +		if (!io_domain) {
> +			ret = -ENOMEM;
> +			goto out;
> +		}
> +		smmu_domain = to_smmu_domain(io_domain);
> +		smmu_domain->d = d;
> +
> +		/* Chain the new context to the domain */
> +		list_add(&io_domain->list, &xen_domain->contexts);
> +	}
> +
> +	ret = arm_smmu_attach_dev(io_domain, dev);
> +	if (ret) {
> +		if (io_domain->ref.counter == 0)
> +			arm_smmu_destroy_iommu_domain(io_domain);
> +	} else {
> +		atomic_inc(&io_domain->ref);
> +	}
> +
> +out:
> +	spin_unlock(&xen_domain->lock);
> +	return ret;
> +}
> +
> +static int arm_smmu_deassign_dev(struct domain *d, struct device *dev)
> +{
> +	struct iommu_domain *io_domain = arm_smmu_get_domain(d, dev);
> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
> +	struct arm_smmu_domain *smmu_domain = to_smmu_domain(io_domain);
> +	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
> +
> +	if (!smmu_domain || smmu_domain->d != d) {
> +		dev_err(dev, " not attached to domain %d\n", d->domain_id);
> +		return -ESRCH;
> +	}
> +
> +	spin_lock(&xen_domain->lock);
> +
> +	arm_smmu_detach_dev(master);
> +	atomic_dec(&io_domain->ref);
> +
> +	if (io_domain->ref.counter == 0)
> +		arm_smmu_destroy_iommu_domain(io_domain);
> +
> +	spin_unlock(&xen_domain->lock);
> +
> +	return 0;
> +}
> +
> +static int arm_smmu_reassign_dev(struct domain *s, struct domain *t,
> +				u8 devfn,  struct device *dev)
> +{
> +	int ret = 0;
> +
> +	/* Don't allow remapping on other domain than hwdom */
> +	if (t && t != hardware_domain)
> +		return -EPERM;
> +
> +	if (t == s)
> +		return 0;
> +
> +	ret = arm_smmu_deassign_dev(s, dev);
> +	if (ret)
> +		return ret;
> +
> +	if (t) {
> +		/* No flags are defined for ARM. */
> +		ret = arm_smmu_assign_dev(t, devfn, dev, 0);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int arm_smmu_iommu_xen_domain_init(struct domain *d)
> +{
> +	struct arm_smmu_xen_domain *xen_domain;
> +
> +	xen_domain = xzalloc(struct arm_smmu_xen_domain);
> +	if (!xen_domain)
> +		return -ENOMEM;
> +
> +	spin_lock_init(&xen_domain->lock);
> +	INIT_LIST_HEAD(&xen_domain->contexts);
> +
> +	dom_iommu(d)->arch.priv = xen_domain;
> +	return 0;
> +
> +}
> +
> +static void __hwdom_init arm_smmu_iommu_hwdom_init(struct domain *d)
> +{
> +}
> +
> +static void arm_smmu_iommu_xen_domain_teardown(struct domain *d)
> +{
> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
> +
> +	ASSERT(list_empty(&xen_domain->contexts));
> +	xfree(xen_domain);
> +}
> +
> +static const struct iommu_ops arm_smmu_iommu_ops = {
> +	.init		= arm_smmu_iommu_xen_domain_init,
> +	.hwdom_init		= arm_smmu_iommu_hwdom_init,
> +	.teardown		= arm_smmu_iommu_xen_domain_teardown,
> +	.iotlb_flush		= arm_smmu_iotlb_flush,
> +	.iotlb_flush_all	= arm_smmu_iotlb_flush_all,
> +	.assign_device		= arm_smmu_assign_dev,
> +	.reassign_device	= arm_smmu_reassign_dev,
> +	.map_page		= arm_iommu_map_page,
> +	.unmap_page		= arm_iommu_unmap_page,
> +	.dt_xlate		= arm_smmu_dt_xlate,
> +	.add_device		= arm_smmu_add_device,
> +};
> +
> +static __init int arm_smmu_dt_init(struct dt_device_node *dev,
> +				const void *data)
> +{
> +	int rc;
> +
> +	/*
> +	 * Even if the device can't be initialized, we don't want to
> +	 * give the SMMU device to dom0.
> +	 */
> +	dt_device_set_used_by(dev, DOMID_XEN);
> +
> +	rc = arm_smmu_device_probe(dt_to_dev(dev));
> +	if (rc)
> +		return rc;
> +
> +	iommu_set_ops(&arm_smmu_iommu_ops);
> +
> +	return 0;
> +}
> +
> +DT_DEVICE_START(smmuv3, "ARM SMMU V3", DEVICE_IOMMU)
> +.dt_match = arm_smmu_of_match,
> +.init = arm_smmu_dt_init,
> +DT_DEVICE_END
> -- 
> 2.17.1
> 



^ permalink raw reply	[flat|nested] 24+ messages in thread

* Re: [PATCH v5 08/10] xen/arm: smmuv3: Use fallthrough pseudo-keyword
  2021-01-20 14:52 ` [PATCH v5 08/10] xen/arm: smmuv3: Use fallthrough pseudo-keyword Rahul Singh
@ 2021-01-20 15:36   ` Bertrand Marquis
  2021-01-20 19:56   ` Stefano Stabellini
  1 sibling, 0 replies; 24+ messages in thread
From: Bertrand Marquis @ 2021-01-20 15:36 UTC (permalink / raw)
  To: Rahul Singh
  Cc: xen-devel, Stefano Stabellini, Julien Grall, Volodymyr Babchuk

Hi Rahul,


> On 20 Jan 2021, at 14:52, Rahul Singh <Rahul.Singh@arm.com> wrote:
> 
> Backport commit df561f6688fef775baa341a0f5d960becd248b11
> "treewide: Use fallthrough pseudo-keyword" from Linux kernel.
> 
> Replace the existing /* fall through */ comments and its variants with
> the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
> fall-through markings when it is the case.
> 
> Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>

Cheers
Bertrand

> ---
> Changes since v3:
> - This patch is introduce in this version.
> Changes since v4:
> - Add more information about the merged patch in commit message.
> ---
> ---
> xen/drivers/passthrough/arm/smmu-v3.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
> index 5ce14850b4..f5f8b4c981 100644
> --- a/xen/drivers/passthrough/arm/smmu-v3.c
> +++ b/xen/drivers/passthrough/arm/smmu-v3.c
> @@ -932,7 +932,6 @@ static void arm_smmu_cmdq_skip_err(struct arm_smmu_device *smmu)
> 		 */
> 		return;
> 	case CMDQ_ERR_CERROR_ILL_IDX:
> -		/* Fallthrough */
> 	default:
> 		break;
> 	}
> @@ -2488,7 +2487,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> 	switch (FIELD_GET(IDR0_STALL_MODEL, reg)) {
> 	case IDR0_STALL_MODEL_FORCE:
> 		smmu->features |= ARM_SMMU_FEAT_STALL_FORCE;
> -		/* Fallthrough */
> +		fallthrough;
> 	case IDR0_STALL_MODEL_STALL:
> 		smmu->features |= ARM_SMMU_FEAT_STALLS;
> 	}
> @@ -2505,7 +2504,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> 	switch (FIELD_GET(IDR0_TTF, reg)) {
> 	case IDR0_TTF_AARCH32_64:
> 		smmu->ias = 40;
> -		/* Fallthrough */
> +		fallthrough;
> 	case IDR0_TTF_AARCH64:
> 		break;
> 	default:
> @@ -2589,7 +2588,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> 	default:
> 		dev_info(smmu->dev,
> 			"unknown output address size. Truncating to 48-bit\n");
> -		/* Fallthrough */
> +		fallthrough;
> 	case IDR5_OAS_48_BIT:
> 		smmu->oas = 48;
> 	}
> -- 
> 2.17.1
> 
> 



^ permalink raw reply	[flat|nested] 24+ messages in thread

* Re: [PATCH v5 08/10] xen/arm: smmuv3: Use fallthrough pseudo-keyword
  2021-01-20 14:52 ` [PATCH v5 08/10] xen/arm: smmuv3: Use fallthrough pseudo-keyword Rahul Singh
  2021-01-20 15:36   ` Bertrand Marquis
@ 2021-01-20 19:56   ` Stefano Stabellini
  1 sibling, 0 replies; 24+ messages in thread
From: Stefano Stabellini @ 2021-01-20 19:56 UTC (permalink / raw)
  To: Rahul Singh
  Cc: xen-devel, bertrand.marquis, Stefano Stabellini, Julien Grall,
	Volodymyr Babchuk

On Wed, 20 Jan 2021, Rahul Singh wrote:
> Backport commit df561f6688fef775baa341a0f5d960becd248b11
> "treewide: Use fallthrough pseudo-keyword" from Linux kernel.
> 
> Replace the existing /* fall through */ comments and its variants with
> the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
> fall-through markings when it is the case.
> 
> Signed-off-by: Rahul Singh <rahul.singh@arm.com>

Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>


> ---
> Changes since v3:
>  - This patch is introduce in this version.
> Changes since v4:
>  - Add more information about the merged patch in commit message.
> ---
> ---
>  xen/drivers/passthrough/arm/smmu-v3.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
> index 5ce14850b4..f5f8b4c981 100644
> --- a/xen/drivers/passthrough/arm/smmu-v3.c
> +++ b/xen/drivers/passthrough/arm/smmu-v3.c
> @@ -932,7 +932,6 @@ static void arm_smmu_cmdq_skip_err(struct arm_smmu_device *smmu)
>  		 */
>  		return;
>  	case CMDQ_ERR_CERROR_ILL_IDX:
> -		/* Fallthrough */
>  	default:
>  		break;
>  	}
> @@ -2488,7 +2487,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>  	switch (FIELD_GET(IDR0_STALL_MODEL, reg)) {
>  	case IDR0_STALL_MODEL_FORCE:
>  		smmu->features |= ARM_SMMU_FEAT_STALL_FORCE;
> -		/* Fallthrough */
> +		fallthrough;
>  	case IDR0_STALL_MODEL_STALL:
>  		smmu->features |= ARM_SMMU_FEAT_STALLS;
>  	}
> @@ -2505,7 +2504,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>  	switch (FIELD_GET(IDR0_TTF, reg)) {
>  	case IDR0_TTF_AARCH32_64:
>  		smmu->ias = 40;
> -		/* Fallthrough */
> +		fallthrough;
>  	case IDR0_TTF_AARCH64:
>  		break;
>  	default:
> @@ -2589,7 +2588,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>  	default:
>  		dev_info(smmu->dev,
>  			"unknown output address size. Truncating to 48-bit\n");
> -		/* Fallthrough */
> +		fallthrough;
>  	case IDR5_OAS_48_BIT:
>  		smmu->oas = 48;
>  	}
> -- 
> 2.17.1
> 


^ permalink raw reply	[flat|nested] 24+ messages in thread

* Re: [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver
  2021-01-20 14:52 ` [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver Rahul Singh
  2021-01-20 15:35   ` Bertrand Marquis
@ 2021-01-20 20:31   ` Stefano Stabellini
  2021-01-21 17:10     ` Rahul Singh
  2021-01-20 21:33   ` Oleksandr
  2 siblings, 1 reply; 24+ messages in thread
From: Stefano Stabellini @ 2021-01-20 20:31 UTC (permalink / raw)
  To: Rahul Singh
  Cc: xen-devel, bertrand.marquis, Andrew Cooper, George Dunlap,
	Ian Jackson, Jan Beulich, Julien Grall, Stefano Stabellini,
	Wei Liu, Paul Durrant, Volodymyr Babchuk

On Wed, 20 Jan 2021, Rahul Singh wrote:
> Add support for ARM architected SMMUv3 implementation. It is based on
> the Linux SMMUv3 driver.
> 
> Driver is currently supported as Tech Preview.
> 
> Major differences with regard to Linux driver are as follows:
> 2. Only Stage-2 translation is supported as compared to the Linux driver
>    that supports both Stage-1 and Stage-2 translations.
> 3. Use P2M  page table instead of creating one as SMMUv3 has the
>    capability to share the page tables with the CPU.
> 4. Tasklets are used in place of threaded IRQ's in Linux for event queue
>    and priority queue IRQ handling.
> 5. Latest version of the Linux SMMUv3 code implements the commands queue
>    access functions based on atomic operations implemented in Linux.
>    Atomic functions used by the commands queue access functions are not
>    implemented in XEN therefore we decided to port the earlier version
>    of the code. Atomic operations are introduced to fix the bottleneck
>    of the SMMU command queue insertion operation. A new algorithm for
>    inserting commands into the queue is introduced, which is lock-free
>    on the fast-path.
>    Consequence of reverting the patch is that the command queue
>    insertion will be slow for large systems as spinlock will be used to
>    serializes accesses from all CPUs to the single queue supported by
>    the hardware. Once the proper atomic operations will be available in
>    XEN the driver can be updated.
> 6. Spin lock is used in place of mutex when attaching a device to the
>    SMMU, as there is no blocking locks implementation available in XEN.
>    This might introduce latency in XEN. Need to investigate before
>    driver is out for tech preview.
> 7. PCI ATS functionality is not supported, as there is no support
>    available in XEN to test the functionality. Code is not tested and
>    compiled. Code is guarded by the flag CONFIG_PCI_ATS.
> 8. MSI interrupts are not supported as there is no support available in
>    XEN to request MSI interrupts. Code is not tested and compiled. Code
>    is guarded by the flag CONFIG_MSI.
> 
> Signed-off-by: Rahul Singh <rahul.singh@arm.com>
> ---
> Changes since v2:
> - added return statement for readx_poll_timeout function.
> - remove iommu_get_dma_cookie and iommu_put_dma_cookie.
> - remove struct arm_smmu_xen_device as not required.
> - move dt_property_match_string to device_tree.c file.
> - replace arm_smmu_*_thread to arm_smmu_*_tasklet to avoid confusion.
> - use ARM_SMMU_REG_SZ as size when map memory to XEN.
> - remove bypass keyword to make sure when device-tree probe is failed we
>   are reporting error and not continuing to configure SMMU in bypass
>   mode.
> - fixed minor comments.
> Changes since v3:
> - Fixed typo for CONFIG_MSI
> - Added back the mutex code
> - Rebase the patch on top of newly added WARN_ON().
> - Remove the direct read of register VTCR_EL2.
> - Fixed minor comments.
> Changes since v4:
> - Replace the ffsll() with ffs64() function.
> - Add code to free resources when probe failed.
> ---
> ---
>  MAINTAINERS                           |   6 +
>  SUPPORT.md                            |   1 +
>  xen/drivers/passthrough/Kconfig       |  11 +
>  xen/drivers/passthrough/arm/Makefile  |   1 +
>  xen/drivers/passthrough/arm/smmu-v3.c | 939 ++++++++++++++++++++++----
>  5 files changed, 830 insertions(+), 128 deletions(-)
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 5079b834c2..14240e8e1e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -249,6 +249,12 @@ F:	xen/include/asm-arm/
>  F:	xen/include/public/arch-arm/
>  F:	xen/include/public/arch-arm.h
>  
> +ARM SMMUv3
> +M:	Bertrand Marquis <bertrand.marquis@arm.com>
> +M:	Rahul Singh <rahul.singh@arm.com>
> +S:	Supported
> +F:	xen/drivers/passthrough/arm/smmu-v3.c
> +
>  Change Log
>  M:	Paul Durrant <paul@xen.org>
>  R:	Community Manager <community.manager@xenproject.org>
> diff --git a/SUPPORT.md b/SUPPORT.md
> index ab02aca5f4..5ee3c8651a 100644
> --- a/SUPPORT.md
> +++ b/SUPPORT.md
> @@ -67,6 +67,7 @@ For the Cortex A57 r0p0 - r1p1, see Errata 832075.
>      Status, Intel VT-d: Supported
>      Status, ARM SMMUv1: Supported, not security supported
>      Status, ARM SMMUv2: Supported, not security supported
> +    Status, ARM SMMUv3: Tech Preview
>      Status, Renesas IPMMU-VMSA: Supported, not security supported
>  
>  ### ARM/GICv3 ITS
> diff --git a/xen/drivers/passthrough/Kconfig b/xen/drivers/passthrough/Kconfig
> index 0036007ec4..341ba92b30 100644
> --- a/xen/drivers/passthrough/Kconfig
> +++ b/xen/drivers/passthrough/Kconfig
> @@ -13,6 +13,17 @@ config ARM_SMMU
>  	  Say Y here if your SoC includes an IOMMU device implementing the
>  	  ARM SMMU architecture.
>  
> +config ARM_SMMU_V3
> +	bool "ARM Ltd. System MMU Version 3 (SMMUv3) Support" if EXPERT
> +	depends on ARM_64
> +	---help---
> +	 Support for implementations of the ARM System MMU architecture
> +	 version 3. Driver is in experimental stage and should not be used in
> +	 production.
> +
> +	 Say Y here if your system includes an IOMMU device implementing
> +	 the ARM SMMUv3 architecture.
> +
>  config IPMMU_VMSA
>  	bool "Renesas IPMMU-VMSA found in R-Car Gen3 SoCs"
>  	depends on ARM_64
> diff --git a/xen/drivers/passthrough/arm/Makefile b/xen/drivers/passthrough/arm/Makefile
> index fcd918ea3e..c5fb3b58a5 100644
> --- a/xen/drivers/passthrough/arm/Makefile
> +++ b/xen/drivers/passthrough/arm/Makefile
> @@ -1,3 +1,4 @@
>  obj-y += iommu.o iommu_helpers.o iommu_fwspec.o
>  obj-$(CONFIG_ARM_SMMU) += smmu.o
>  obj-$(CONFIG_IPMMU_VMSA) += ipmmu-vmsa.o
> +obj-$(CONFIG_ARM_SMMU_V3) += smmu-v3.o
> diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
> index 2dfadc6a65..dd0540bb5f 100644
> --- a/xen/drivers/passthrough/arm/smmu-v3.c
> +++ b/xen/drivers/passthrough/arm/smmu-v3.c
> @@ -2,37 +2,263 @@
>  /*
>   * IOMMU API for ARM architected SMMUv3 implementations.
>   *
> + * Based on Linux's SMMUv3 driver:
> + *    drivers/iommu/arm-smmu-v3.c
> + *    commit: ab435ce49bd1d02e33dfec24f76955dc1196970b
> + * and Xen's SMMU driver:
> + *    xen/drivers/passthrough/arm/smmu.c
> + *
> + * Major differences with regard to Linux driver are as follows:
> + *  1. Driver is currently supported as Tech Preview.
> + *  2. Only Stage-2 translation is supported as compared to the Linux driver
> + *     that supports both Stage-1 and Stage-2 translations.
> + *  3. Use P2M  page table instead of creating one as SMMUv3 has the
> + *     capability to share the page tables with the CPU.
> + *  4. Tasklets are used in place of threaded IRQ's in Linux for event queue
> + *     and priority queue IRQ handling.
> + *  5. Latest version of the Linux SMMUv3 code implements the commands queue
> + *     access functions based on atomic operations implemented in Linux.
> + *     Atomic functions used by the commands queue access functions are not
> + *     implemented in XEN therefore we decided to port the earlier version
> + *     of the code. Atomic operations are introduced to fix the bottleneck of
> + *     the SMMU command queue insertion operation. A new algorithm for
> + *     inserting commands into the queue is introduced, which is
> + *     lock-free on the fast-path.
> + *     Consequence of reverting the patch is that the command queue insertion
> + *     will be slow for large systems as spinlock will be used to serializes
> + *     accesses from all CPUs to the single queue supported by the hardware.
> + *     Once the proper atomic operations will be available in XEN the driver
> + *     can be updated.
> + *  6. Spin lock is used in place of Mutex when attaching a device to the SMMU,
> + *     as there is no blocking locks implementation available in XEN.This might
> + *     introduce latency in XEN. Need to investigate before driver is out for
> + *     Tech Preview.
> + *  7. PCI ATS functionality is not supported, as there is no support available
> + *     in XEN to test the functionality. Code is not tested and compiled. Code
> + *     is guarded by the flag CONFIG_PCI_ATS.
> + *  8. MSI interrupts are not supported as there is no support available
> + *     in XEN to request MSI interrupts. Code is not tested and compiled. Code
> + *     is guarded by the flag CONFIG_MSI.
> + *
> + * Following functionality should be supported before driver is out for tech
> + * preview
> + *
> + *  1. Investigate the timing analysis of using spin lock in place of mutex
> + *     when attaching devices to SMMU.
> + *  2. Merged the latest Linux SMMUv3 driver code once atomic operation is
> + *     available in XEN.
> + *  3. PCI ATS and MSI interrupts should be supported.
> + *  4. Investigate side-effect of using tasklet in place of threaded IRQ and
> + *     fix if any.
> + *
>   * Copyright (C) 2015 ARM Limited
>   *
>   * Author: Will Deacon <will.deacon@arm.com>
>   *
> - * This driver is powered by bad coffee and bombay mix.
> + * Copyright (C) 2020 Arm Ltd
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program.  If not, see <http://www.gnu.org/licenses/>.
> + *
>   */
>  
> -#include <linux/acpi.h>
> -#include <linux/acpi_iort.h>
> -#include <linux/bitfield.h>
> -#include <linux/bitops.h>
> -#include <linux/crash_dump.h>
> -#include <linux/delay.h>
> -#include <linux/dma-iommu.h>
> -#include <linux/err.h>
> -#include <linux/interrupt.h>
> -#include <linux/io-pgtable.h>
> -#include <linux/iommu.h>
> -#include <linux/iopoll.h>
> -#include <linux/module.h>
> -#include <linux/msi.h>
> -#include <linux/of.h>
> -#include <linux/of_address.h>
> -#include <linux/of_iommu.h>
> -#include <linux/of_platform.h>
> -#include <linux/pci.h>
> -#include <linux/pci-ats.h>
> -#include <linux/platform_device.h>
> -
> -#include <linux/amba/bus.h>
> +#include <xen/acpi.h>
> +#include <xen/config.h>
> +#include <xen/delay.h>
> +#include <xen/errno.h>
> +#include <xen/err.h>
> +#include <xen/irq.h>
> +#include <xen/lib.h>
> +#include <xen/list.h>
> +#include <xen/mm.h>
> +#include <xen/rbtree.h>
> +#include <xen/sched.h>
> +#include <xen/sizes.h>
> +#include <xen/vmap.h>
> +#include <asm/atomic.h>
> +#include <asm/device.h>
> +#include <asm/io.h>
> +#include <asm/iommu_fwspec.h>
> +#include <asm/platform.h>
> +
> +
> +#define ARM_SMMU_VTCR_SH_IS		3
> +#define ARM_SMMU_VTCR_RGN_WBWA		1
> +#define ARM_SMMU_VTCR_TG0_4K		0
> +#define ARM_SMMU_VTCR_PS_32_BIT		0x0ULL
> +#define ARM_SMMU_VTCR_PS_36_BIT		0x1ULL
> +#define ARM_SMMU_VTCR_PS_40_BIT		0x2ULL
> +#define ARM_SMMU_VTCR_PS_42_BIT		0x3ULL
> +#define ARM_SMMU_VTCR_PS_44_BIT		0x4ULL
> +#define ARM_SMMU_VTCR_PS_48_BIT		0x5ULL
> +#define ARM_SMMU_VTCR_PS_52_BIT		0x6ULL
> +
> +/* Linux compatibility functions. */
> +typedef paddr_t		dma_addr_t;
> +typedef paddr_t		phys_addr_t;
> +typedef unsigned int		gfp_t;
> +
> +#define platform_device		device
> +
> +#define GFP_KERNEL		0
> +
> +/* Alias to Xen lock functions */
> +#define mutex spinlock
> +#define mutex_init spin_lock_init
> +#define mutex_lock spin_lock
> +#define mutex_unlock spin_unlock
> +
> +/* Device logger functions */
> +#define dev_name(dev)	dt_node_full_name(dev->of_node)
> +#define dev_dbg(dev, fmt, ...)			\
> +	printk(XENLOG_DEBUG "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
> +#define dev_notice(dev, fmt, ...)		\
> +	printk(XENLOG_INFO "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
> +#define dev_warn(dev, fmt, ...)			\
> +	printk(XENLOG_WARNING "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
> +#define dev_err(dev, fmt, ...)			\
> +	printk(XENLOG_ERR "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
> +#define dev_info(dev, fmt, ...)			\
> +	printk(XENLOG_INFO "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
> +#define dev_err_ratelimited(dev, fmt, ...)			\
> +	printk(XENLOG_ERR "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
> +
> +/*
> + * Periodically poll an address and wait between reads in us until a
> + * condition is met or a timeout occurs.
> + *
> + * @return: 0 when cond met, -ETIMEDOUT upon timeout
> + */
> +#define readx_poll_timeout(op, addr, val, cond, sleep_us, timeout_us) \
> +({ \
> +	s_time_t deadline = NOW() + MICROSECS(timeout_us); \
> +	for (;;) { \
> +		(val) = op(addr); \
> +		if (cond) \
> +			break; \
> +		if (NOW() > deadline) { \
> +			(val) = op(addr); \
> +			break; \
> +		} \
> +		udelay(sleep_us); \
> +	} \
> +	(cond) ? 0 : -ETIMEDOUT; \
> +})
> +
> +#define readl_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us)	\
> +	readx_poll_timeout(readl_relaxed, addr, val, cond, delay_us, timeout_us)
> +
> +#define FIELD_PREP(_mask, _val)			\
> +	(((typeof(_mask))(_val) << (ffs64(_mask) - 1)) & (_mask))
> +
> +#define FIELD_GET(_mask, _reg)			\
> +	((typeof(_mask))(((_reg) & (_mask)) >> (ffs64(_mask) - 1)))
> +
> +/*
> + * Helpers for DMA allocation. Just the function name is reused for
> + * porting code, these allocation are not managed allocations
> + */
> +static void *dmam_alloc_coherent(struct device *dev, size_t size,
> +				paddr_t *dma_handle, gfp_t gfp)
> +{
> +	void *vaddr;
> +	unsigned long alignment = size;
> +
> +	/*
> +	 * _xzalloc requires that the (align & (align -1)) = 0. Most of the
> +	 * allocations in SMMU code should send the right value for size. In
> +	 * case this is not true print a warning and align to the size of a
> +	 * (void *)
> +	 */
> +	if (size & (size - 1)) {
> +		printk(XENLOG_WARNING "SMMUv3: Fixing alignment for the DMA buffer\n");
> +		alignment = sizeof(void *);
> +	}
> +
> +	vaddr = _xzalloc(size, alignment);
> +	if (!vaddr) {
> +		printk(XENLOG_ERR "SMMUv3: DMA allocation failed\n");
> +		return NULL;
> +	}
> +
> +	*dma_handle = virt_to_maddr(vaddr);
> +
> +	return vaddr;
> +}
> +
> +
> +/* Xen specific code. */
> +struct iommu_domain {
> +	/* Runtime SMMU configuration for this iommu_domain */
> +	atomic_t		ref;
> +	/*
> +	 * Used to link iommu_domain contexts for a same domain.
> +	 * There is at least one per-SMMU to used by the domain.
> +	 */
> +	struct list_head		list;
> +};
> +
> +/* Describes information required for a Xen domain */
> +struct arm_smmu_xen_domain {
> +	spinlock_t		lock;
> +
> +	/* List of iommu domains associated to this domain */
> +	struct list_head	contexts;
> +};
> +
> +
> +/* Keep a list of devices associated with this driver */
> +static DEFINE_SPINLOCK(arm_smmu_devices_lock);
> +static LIST_HEAD(arm_smmu_devices);
> +
> +static inline void *dev_iommu_priv_get(struct device *dev)
> +{
> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> +
> +	return fwspec && fwspec->iommu_priv ? fwspec->iommu_priv : NULL;
> +}
> +
> +static inline void dev_iommu_priv_set(struct device *dev, void *priv)
> +{
> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> +
> +	fwspec->iommu_priv = priv;
> +}
> +
> +static int platform_get_irq_byname_optional(struct device *dev,
> +				const char *name)
> +{
> +	int index, ret;
> +	struct dt_device_node *np  = dev_to_dt(dev);
> +
> +	if (unlikely(!name))
> +		return -EINVAL;
> +
> +	index = dt_property_match_string(np, "interrupt-names", name);
> +	if (index < 0) {
> +		dev_info(dev, "IRQ %s not found\n", name);
> +		return index;
> +	}
> +
> +	ret = platform_get_irq(np, index);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to get irq index %d\n", index);
> +		return -ENODEV;
> +	}
> +
> +	return ret;
> +}
>  
> +/* Start of Linux SMMUv3 code */
>  /* MMIO registers */
>  #define ARM_SMMU_IDR0			0x0
>  #define IDR0_ST_LVL			GENMASK(28, 27)
> @@ -402,6 +628,7 @@ enum pri_resp {
>  	PRI_RESP_SUCC = 2,
>  };
>  
> +#ifdef CONFIG_MSI
>  enum arm_smmu_msi_index {
>  	EVTQ_MSI_INDEX,
>  	GERROR_MSI_INDEX,
> @@ -426,6 +653,7 @@ static phys_addr_t arm_smmu_msi_cfg[ARM_SMMU_MAX_MSIS][3] = {
>  		ARM_SMMU_PRIQ_IRQ_CFG2,
>  	},
>  };
> +#endif /* CONFIG_MSI */
>  
>  struct arm_smmu_cmdq_ent {
>  	/* Common fields */
> @@ -613,8 +841,13 @@ struct arm_smmu_device {
>  		u64			padding;
>  	};
>  
> -	/* IOMMU core code handle */
> -	struct iommu_device		iommu;
> +	/* Need to keep a list of SMMU devices */
> +	struct list_head		devices;
> +
> +	/* Tasklets for handling evts/faults and pci page request IRQs*/
> +	struct tasklet		evtq_irq_tasklet;
> +	struct tasklet		priq_irq_tasklet;
> +	struct tasklet		combined_irq_tasklet;
>  };
>  
>  /* SMMU private data for each master */
> @@ -646,6 +879,9 @@ struct arm_smmu_domain {
>  	enum arm_smmu_domain_stage	stage;
>  	struct arm_smmu_s2_cfg	s2_cfg;
>  
> +	/* Xen domain associated with this SMMU domain */
> +	struct domain		*d;
> +
>  	struct iommu_domain		domain;
>  
>  	struct list_head		devices;
> @@ -984,6 +1220,7 @@ static void arm_smmu_cmdq_issue_cmd(struct arm_smmu_device *smmu,
>  	spin_unlock_irqrestore(&smmu->cmdq.lock, flags);
>  }
>  
> +#ifdef CONFIG_MSI
>  /*
>   * The difference between val and sync_idx is bounded by the maximum size of
>   * a queue at 2^20 entries, so 32 bits is plenty for wrap-safe arithmetic.
> @@ -1027,6 +1264,13 @@ static int __arm_smmu_cmdq_issue_sync_msi(struct arm_smmu_device *smmu)
>  
>  	return __arm_smmu_sync_poll_msi(smmu, ent.sync.msidata);
>  }
> +#else
> +static inline int __arm_smmu_cmdq_issue_sync_msi(struct arm_smmu_device *smmu)
> +{
> +	return 0;
> +}
> +#endif /* CONFIG_MSI */
> +
>  
>  static int __arm_smmu_cmdq_issue_sync(struct arm_smmu_device *smmu)
>  {
> @@ -1069,7 +1313,7 @@ arm_smmu_write_strtab_l1_desc(__le64 *dst, struct arm_smmu_strtab_l1_desc *desc)
>  	val |= desc->l2ptr_dma & STRTAB_L1_DESC_L2PTR_MASK;
>  
>  	/* See comment in arm_smmu_write_ctx_desc() */
> -	WRITE_ONCE(*dst, cpu_to_le64(val));
> +	write_atomic(dst, cpu_to_le64(val));
>  }
>  
>  static void arm_smmu_sync_ste_for_sid(struct arm_smmu_device *smmu, u32 sid)
> @@ -1184,7 +1428,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
>  						 STRTAB_STE_1_EATS_TRANS));
>  
>  	arm_smmu_sync_ste_for_sid(smmu, sid);
> -	WRITE_ONCE(dst[0], cpu_to_le64(val));
> +	write_atomic(&dst[0], cpu_to_le64(val));
>  	arm_smmu_sync_ste_for_sid(smmu, sid);
>  
>  	/* It's likely that we'll want to use the new STE soon */
> @@ -1231,7 +1475,7 @@ static int arm_smmu_init_l2_strtab(struct arm_smmu_device *smmu, u32 sid)
>  }
>  
>  /* IRQ and event handlers */
> -static irqreturn_t arm_smmu_evtq_thread(int irq, void *dev)
> +static void arm_smmu_evtq_tasklet(void *dev)
>  {
>  	int i;
>  	struct arm_smmu_device *smmu = dev;
> @@ -1261,7 +1505,6 @@ static irqreturn_t arm_smmu_evtq_thread(int irq, void *dev)
>  	/* Sync our overflow flag, as we believe we're up to speed */
>  	llq->cons = Q_OVF(llq->prod) | Q_WRP(llq, llq->cons) |
>  		    Q_IDX(llq, llq->cons);
> -	return IRQ_HANDLED;
>  }
>  
>  static void arm_smmu_handle_ppr(struct arm_smmu_device *smmu, u64 *evt)
> @@ -1302,7 +1545,7 @@ static void arm_smmu_handle_ppr(struct arm_smmu_device *smmu, u64 *evt)
>  	}
>  }
>  
> -static irqreturn_t arm_smmu_priq_thread(int irq, void *dev)
> +static void arm_smmu_priq_tasklet(void *dev)
>  {
>  	struct arm_smmu_device *smmu = dev;
>  	struct arm_smmu_queue *q = &smmu->priq.q;
> @@ -1321,12 +1564,12 @@ static irqreturn_t arm_smmu_priq_thread(int irq, void *dev)
>  	llq->cons = Q_OVF(llq->prod) | Q_WRP(llq, llq->cons) |
>  		      Q_IDX(llq, llq->cons);
>  	queue_sync_cons_out(q);
> -	return IRQ_HANDLED;
>  }
>  
>  static int arm_smmu_device_disable(struct arm_smmu_device *smmu);
>  
> -static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
> +static void arm_smmu_gerror_handler(int irq, void *dev,
> +				struct cpu_user_regs *regs)
>  {
>  	u32 gerror, gerrorn, active;
>  	struct arm_smmu_device *smmu = dev;
> @@ -1336,7 +1579,7 @@ static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
>  
>  	active = gerror ^ gerrorn;
>  	if (!(active & GERROR_ERR_MASK))
> -		return IRQ_NONE; /* No errors pending */
> +		return; /* No errors pending */
>  
>  	dev_warn(smmu->dev,
>  		 "unexpected global error reported (0x%08x), this could be serious\n",
> @@ -1369,26 +1612,44 @@ static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
>  		arm_smmu_cmdq_skip_err(smmu);
>  
>  	writel(gerror, smmu->base + ARM_SMMU_GERRORN);
> -	return IRQ_HANDLED;
>  }
>  
> -static irqreturn_t arm_smmu_combined_irq_thread(int irq, void *dev)
> +static void arm_smmu_combined_irq_handler(int irq, void *dev,
> +				struct cpu_user_regs *regs)
>  {
>  	struct arm_smmu_device *smmu = dev;
>  
> -	arm_smmu_evtq_thread(irq, dev);
> +	arm_smmu_gerror_handler(irq, dev, regs);
> +
> +	tasklet_schedule(&(smmu->combined_irq_tasklet));
> +}
> +
> +static void arm_smmu_combined_irq_tasklet(void *dev)
> +{
> +	struct arm_smmu_device *smmu = dev;
> +
> +	arm_smmu_evtq_tasklet(dev);
>  	if (smmu->features & ARM_SMMU_FEAT_PRI)
> -		arm_smmu_priq_thread(irq, dev);
> +		arm_smmu_priq_tasklet(dev);
> +}
> +
> +static void arm_smmu_evtq_irq_tasklet(int irq, void *dev,
> +				struct cpu_user_regs *regs)
> +{
> +	struct arm_smmu_device *smmu = dev;
>  
> -	return IRQ_HANDLED;
> +	tasklet_schedule(&(smmu->evtq_irq_tasklet));
>  }
>  
> -static irqreturn_t arm_smmu_combined_irq_handler(int irq, void *dev)
> +static void arm_smmu_priq_irq_tasklet(int irq, void *dev,
> +				struct cpu_user_regs *regs)
>  {
> -	arm_smmu_gerror_handler(irq, dev);
> -	return IRQ_WAKE_THREAD;
> +	struct arm_smmu_device *smmu = dev;
> +
> +	tasklet_schedule(&(smmu->priq_irq_tasklet));
>  }
>  
> +#ifdef CONFIG_PCI_ATS
>  static void
>  arm_smmu_atc_inv_to_cmd(int ssid, unsigned long iova, size_t size,
>  			struct arm_smmu_cmdq_ent *cmd)
> @@ -1495,6 +1756,7 @@ static int arm_smmu_atc_inv_domain(struct arm_smmu_domain *smmu_domain,
>  
>  	return ret ? -ETIMEDOUT : 0;
>  }
> +#endif /* CONFIG_PCI_ATS */
>  
>  static void arm_smmu_tlb_inv_context(void *cookie)
>  {
> @@ -1525,7 +1787,7 @@ static struct iommu_domain *arm_smmu_domain_alloc(void)
>  	 * We can't really do anything meaningful until we've added a
>  	 * master.
>  	 */
> -	smmu_domain = kzalloc(sizeof(*smmu_domain), GFP_KERNEL);
> +	smmu_domain = xzalloc(struct arm_smmu_domain);
>  	if (!smmu_domain)
>  		return NULL;
>  
> @@ -1563,7 +1825,7 @@ static void arm_smmu_domain_free(struct iommu_domain *domain)
>  	if (cfg->vmid)
>  		arm_smmu_bitmap_free(smmu->vmid_map, cfg->vmid);
>  
> -	kfree(smmu_domain);
> +	xfree(smmu_domain);
>  }
>  
>  
> @@ -1576,6 +1838,44 @@ static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
>  	struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
>  	typeof(&arm_lpae_s2_cfg.vtcr) vtcr = &arm_lpae_s2_cfg.vtcr;
>  
> +	vtcr->sh = ARM_SMMU_VTCR_SH_IS;
> +	vtcr->irgn = ARM_SMMU_VTCR_RGN_WBWA;
> +	vtcr->orgn = ARM_SMMU_VTCR_RGN_WBWA;
> +
> +	BUILD_BUG_ON(PAGE_SIZE != SZ_4K);
> +	vtcr->tg = ARM_SMMU_VTCR_TG0_4K;
> +
> +	switch (smmu->oas) {
> +	case 32:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_32_BIT;
> +		break;
> +	case 36:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_36_BIT;
> +		break;
> +	case 40:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_40_BIT;
> +		break;
> +	case 42:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_42_BIT;
> +		break;
> +	case 44:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_44_BIT;
> +		break;
> +	case 48:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_48_BIT;
> +		break;
> +	case 52:
> +		vtcr->ps = ARM_SMMU_VTCR_PS_52_BIT;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	vtcr->tsz = 64 - p2m_ipa_bits;
> +	vtcr->sl = 2 - P2M_ROOT_LEVEL;
> +
> +	arm_lpae_s2_cfg.vttbr  = page_to_maddr(smmu_domain->d->arch.p2m.root);
> +
>  	vmid = arm_smmu_bitmap_alloc(smmu->vmid_map, smmu->vmid_bits);
>  	if (vmid < 0)
>  		return vmid;
> @@ -1589,6 +1889,11 @@ static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
>  			  FIELD_PREP(STRTAB_STE_2_VTCR_S2SH0, vtcr->sh) |
>  			  FIELD_PREP(STRTAB_STE_2_VTCR_S2TG, vtcr->tg) |
>  			  FIELD_PREP(STRTAB_STE_2_VTCR_S2PS, vtcr->ps);
> +
> +	printk(XENLOG_DEBUG
> +		   "SMMUv3: d%u: vmid 0x%x vtcr 0x%"PRIpaddr" p2maddr 0x%"PRIpaddr"\n",
> +		   smmu_domain->d->domain_id, cfg->vmid, cfg->vtcr, cfg->vttbr);
> +
>  	return 0;
>  }
>  
> @@ -1650,6 +1955,7 @@ static void arm_smmu_install_ste_for_dev(struct arm_smmu_master *master)
>  	}
>  }
>  
> +#ifdef CONFIG_PCI_ATS
>  static bool arm_smmu_ats_supported(struct arm_smmu_master *master)
>  {
>  	struct device *dev = master->dev;
> @@ -1748,6 +2054,23 @@ static void arm_smmu_disable_pasid(struct arm_smmu_master *master)
>  
>  	pci_disable_pasid(pdev);
>  }
> +#else
> +static inline bool arm_smmu_ats_supported(struct arm_smmu_master *master)
> +{
> +	return false;
> +}
> +
> +static inline void arm_smmu_enable_ats(struct arm_smmu_master *master) { }
> +
> +static inline void arm_smmu_disable_ats(struct arm_smmu_master *master) { }
> +
> +static inline int arm_smmu_enable_pasid(struct arm_smmu_master *master)
> +{
> +	return 0;
> +}
> +
> +static inline void arm_smmu_disable_pasid(struct arm_smmu_master *master) { }
> +#endif /* CONFIG_PCI_ATS */
>  
>  static void arm_smmu_detach_dev(struct arm_smmu_master *master)
>  {
> @@ -1830,8 +2153,10 @@ static bool arm_smmu_sid_in_range(struct arm_smmu_device *smmu, u32 sid)
>  
>  	return sid < limit;
>  }
> +/* Forward declaration */
> +static struct arm_smmu_device *arm_smmu_get_by_dev(struct device *dev);
>  
> -static struct iommu_device *arm_smmu_probe_device(struct device *dev)
> +static int arm_smmu_add_device(u8 devfn, struct device *dev)
>  {
>  	int i, ret;
>  	struct arm_smmu_device *smmu;
> @@ -1839,14 +2164,15 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
>  	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
>  
>  	if (!fwspec)
> -		return ERR_PTR(-ENODEV);
> +		return -ENODEV;
>  
> -	if (WARN_ON_ONCE(dev_iommu_priv_get(dev)))
> -		return ERR_PTR(-EBUSY);
> +	smmu = arm_smmu_get_by_dev(fwspec->iommu_dev);
> +	if (!smmu)
> +		return -ENODEV;
>  
> -	master = kzalloc(sizeof(*master), GFP_KERNEL);
> +	master = xzalloc(struct arm_smmu_master);
>  	if (!master)
> -		return ERR_PTR(-ENOMEM);
> +		return -ENOMEM;
>  
>  	master->dev = dev;
>  	master->smmu = smmu;
> @@ -1881,17 +2207,36 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
>  	 */
>  	arm_smmu_enable_pasid(master);
>  
> -	return &smmu->iommu;
> +	return 0;
>  
>  err_free_master:
> -	kfree(master);
> +	xfree(master);
>  	dev_iommu_priv_set(dev, NULL);
> -	return ERR_PTR(ret);
> +	return ret;
>  }
>  
> -static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args)
> +static int arm_smmu_dt_xlate(struct device *dev,
> +				const struct dt_phandle_args *args)
>  {
> -	return iommu_fwspec_add_ids(dev, args->args, 1);
> +	int ret;
> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> +
> +	ret = iommu_fwspec_add_ids(dev, args->args, 1);
> +	if (ret)
> +		return ret;
> +
> +	if (dt_device_is_protected(dev_to_dt(dev))) {
> +		dev_err(dev, "Already added to SMMUv3\n");
> +		return -EEXIST;
> +	}
> +
> +	/* Let Xen know that the master device is protected by an IOMMU. */
> +	dt_device_set_protected(dev_to_dt(dev));
> +
> +	dev_info(dev, "Added master device (SMMUv3 %s StreamIds %u)\n",
> +			dev_name(fwspec->iommu_dev), fwspec->num_ids);
> +
> +	return 0;
>  }
>  
>  /* Probing and initialisation functions */
> @@ -1972,7 +2317,7 @@ static int arm_smmu_init_l1_strtab(struct arm_smmu_device *smmu)
>  	size_t size = sizeof(*cfg->l1_desc) * cfg->num_l1_ents;
>  	void *strtab = smmu->strtab_cfg.strtab;
>  
> -	cfg->l1_desc = devm_kzalloc(smmu->dev, size, GFP_KERNEL);
> +	cfg->l1_desc = _xzalloc(size, sizeof(void *));
>  	if (!cfg->l1_desc) {
>  		dev_err(smmu->dev, "failed to allocate l1 stream table desc\n");
>  		return -ENOMEM;
> @@ -2118,6 +2463,7 @@ static int arm_smmu_update_gbpa(struct arm_smmu_device *smmu, u32 set, u32 clr)
>  	return ret;
>  }
>  
> +#ifdef CONFIG_MSI
>  static void arm_smmu_free_msis(void *data)
>  {
>  	struct device *dev = data;
> @@ -2188,8 +2534,35 @@ static void arm_smmu_setup_msis(struct arm_smmu_device *smmu)
>  	/* Add callback to free MSIs on teardown */
>  	devm_add_action(dev, arm_smmu_free_msis, dev);
>  }
> +#else
> +static inline void arm_smmu_setup_msis(struct arm_smmu_device *smmu) { }
> +#endif /* CONFIG_MSI */
>  
> -static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
> +static void arm_smmu_free_irqs(struct arm_smmu_device *smmu)
> +{
> +	int irq;
> +
> +	irq = smmu->combined_irq;
> +	if (irq)
> +		release_irq(irq, smmu);
> +	else {
> +		irq = smmu->evtq.q.irq;
> +		if (irq)
> +			release_irq(irq, smmu);
> +
> +		irq = smmu->gerr_irq;
> +		if (irq)
> +			release_irq(irq, smmu);
> +
> +		if (smmu->features & ARM_SMMU_FEAT_PRI) {
> +			irq = smmu->priq.q.irq;
> +			if (irq)
> +				release_irq(irq, smmu);
> +		}
> +	}
> +}
> +
> +static int arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
>  {
>  	int irq, ret;
>  
> @@ -2198,22 +2571,24 @@ static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
>  	/* Request interrupt lines */
>  	irq = smmu->evtq.q.irq;
>  	if (irq) {
> -		ret = devm_request_threaded_irq(smmu->dev, irq, NULL,
> -						arm_smmu_evtq_thread,
> -						IRQF_ONESHOT,
> +		ret = request_irq(irq, 0, arm_smmu_evtq_irq_tasklet,
>  						"arm-smmu-v3-evtq", smmu);
> -		if (ret < 0)
> +		if (ret < 0) {
>  			dev_warn(smmu->dev, "failed to enable evtq irq\n");
> +			return ret;
> +		}
>  	} else {
>  		dev_warn(smmu->dev, "no evtq irq - events will not be reported!\n");
>  	}
>  
>  	irq = smmu->gerr_irq;
>  	if (irq) {
> -		ret = devm_request_irq(smmu->dev, irq, arm_smmu_gerror_handler,
> -				       0, "arm-smmu-v3-gerror", smmu);
> -		if (ret < 0)
> +		ret = request_irq(irq, 0, arm_smmu_gerror_handler,
> +						"arm-smmu-v3-gerror", smmu);
> +		if (ret < 0) {
>  			dev_warn(smmu->dev, "failed to enable gerror irq\n");
> +			goto err_free_evtq_irq;
> +		}
>  	} else {
>  		dev_warn(smmu->dev, "no gerr irq - errors will not be reported!\n");
>  	}
> @@ -2221,18 +2596,30 @@ static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
>  	if (smmu->features & ARM_SMMU_FEAT_PRI) {
>  		irq = smmu->priq.q.irq;
>  		if (irq) {
> -			ret = devm_request_threaded_irq(smmu->dev, irq, NULL,
> -							arm_smmu_priq_thread,
> -							IRQF_ONESHOT,
> -							"arm-smmu-v3-priq",
> -							smmu);
> -			if (ret < 0)
> +			ret = request_irq(irq, 0, arm_smmu_priq_irq_tasklet,
> +							"arm-smmu-v3-priq", smmu);
> +			if (ret < 0) {
>  				dev_warn(smmu->dev,
>  					 "failed to enable priq irq\n");
> +				goto err_free_gerr_irq;
> +			}
>  		} else {
>  			dev_warn(smmu->dev, "no priq irq - PRI will be broken\n");
>  		}
>  	}
> +
> +	return 0;
> +
> +err_free_gerr_irq:
> +	irq = smmu->gerr_irq;
> +	if (irq)
> +		release_irq(irq, smmu);
> +err_free_evtq_irq:
> +	irq = smmu->evtq.q.irq;
> +	if (irq)
> +		release_irq(irq, smmu);
> +
> +	return ret;
>  }
>  
>  static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
> @@ -2254,15 +2641,19 @@ static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
>  		 * Cavium ThunderX2 implementation doesn't support unique irq
>  		 * lines. Use a single irq line for all the SMMUv3 interrupts.
>  		 */
> -		ret = devm_request_threaded_irq(smmu->dev, irq,
> -					arm_smmu_combined_irq_handler,
> -					arm_smmu_combined_irq_thread,
> -					IRQF_ONESHOT,
> -					"arm-smmu-v3-combined-irq", smmu);
> -		if (ret < 0)
> +		ret = request_irq(irq, 0, arm_smmu_combined_irq_handler,
> +						"arm-smmu-v3-combined-irq", smmu);
> +		if (ret < 0) {
>  			dev_warn(smmu->dev, "failed to enable combined irq\n");
> -	} else
> -		arm_smmu_setup_unique_irqs(smmu);
> +			return ret;
> +		}
> +	} else {
> +		ret = arm_smmu_setup_unique_irqs(smmu);
> +		if (ret) {
> +			dev_warn(smmu->dev, "failed to setup unique irqs\n");
> +			return ret;
> +		}
> +	}
>  
>  	if (smmu->features & ARM_SMMU_FEAT_PRI)
>  		irqen_flags |= IRQ_CTRL_PRIQ_IRQEN;
> @@ -2270,10 +2661,16 @@ static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
>  	/* Enable interrupt generation on the SMMU */
>  	ret = arm_smmu_write_reg_sync(smmu, irqen_flags,
>  				      ARM_SMMU_IRQ_CTRL, ARM_SMMU_IRQ_CTRLACK);
> -	if (ret)
> +	if (ret) {
>  		dev_warn(smmu->dev, "failed to enable irqs\n");
> +		goto err_free_irqs;
> +	}
>  
>  	return 0;
> +
> +err_free_irqs:
> +	arm_smmu_free_irqs(smmu);
> +	return ret;
>  }
>  
>  static int arm_smmu_device_disable(struct arm_smmu_device *smmu)
> @@ -2287,7 +2684,7 @@ static int arm_smmu_device_disable(struct arm_smmu_device *smmu)
>  	return ret;
>  }
>  
> -static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
> +static int arm_smmu_device_reset(struct arm_smmu_device *smmu)
>  {
>  	int ret;
>  	u32 reg, enables;
> @@ -2297,7 +2694,7 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
>  	reg = readl_relaxed(smmu->base + ARM_SMMU_CR0);
>  	if (reg & CR0_SMMUEN) {
>  		dev_warn(smmu->dev, "SMMU currently enabled! Resetting...\n");
> -		WARN_ON(is_kdump_kernel() && !disable_bypass);
> +		WARN_ON(!disable_bypass);
>  		arm_smmu_update_gbpa(smmu, GBPA_ABORT, 0);
>  	}
>  
> @@ -2401,25 +2798,32 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
>  		return ret;
>  	}
>  
> -	if (is_kdump_kernel())
> -		enables &= ~(CR0_EVTQEN | CR0_PRIQEN);
> +	/* Initialize tasklets for threaded IRQs*/
> +	tasklet_init(&smmu->evtq_irq_tasklet, arm_smmu_evtq_tasklet, smmu);
> +	tasklet_init(&smmu->priq_irq_tasklet, arm_smmu_priq_tasklet, smmu);
> +	tasklet_init(&smmu->combined_irq_tasklet, arm_smmu_combined_irq_tasklet,
> +				 smmu);
>  
>  	/* Enable the SMMU interface, or ensure bypass */
> -	if (!bypass || disable_bypass) {
> +	if (disable_bypass) {
>  		enables |= CR0_SMMUEN;
>  	} else {
>  		ret = arm_smmu_update_gbpa(smmu, 0, GBPA_ABORT);
>  		if (ret)
> -			return ret;
> +			goto err_free_irqs;
>  	}
>  	ret = arm_smmu_write_reg_sync(smmu, enables, ARM_SMMU_CR0,
>  				      ARM_SMMU_CR0ACK);
>  	if (ret) {
>  		dev_err(smmu->dev, "failed to enable SMMU interface\n");
> -		return ret;
> +		goto err_free_irqs;
>  	}
>  
>  	return 0;
> +
> +err_free_irqs:
> +	arm_smmu_free_irqs(smmu);
> +	return ret;
>  }
>  
>  static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
> @@ -2470,8 +2874,10 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>  	if (reg & IDR0_SEV)
>  		smmu->features |= ARM_SMMU_FEAT_SEV;
>  
> +#ifdef CONFIG_MSI
>  	if (reg & IDR0_MSI)
>  		smmu->features |= ARM_SMMU_FEAT_MSI;
> +#endif
>  
>  	if (reg & IDR0_HYP)
>  		smmu->features |= ARM_SMMU_FEAT_HYP;
> @@ -2496,7 +2902,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>  		smmu->features |= ARM_SMMU_FEAT_TRANS_S2;
>  
>  	if (!(reg & IDR0_S2P)) {
> -		dev_err(smmu->dev, "no translation support!\n");
> +		dev_err(smmu->dev, "no stage-2 translation support!\n");
>  		return -ENXIO;
>  	}
>  
> @@ -2593,8 +2999,12 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>  		smmu->oas = 48;
>  	}
>  
> +	smmu->oas = min_t(unsigned long, PADDR_BITS, smmu->oas);
>  	smmu->ias = max(smmu->ias, smmu->oas);
>  
> +	/* Xen: Set maximum Stage-2 input size supported by the SMMU. */
> +	p2m_restrict_ipa_bits(smmu->ias);
> +
>  	dev_info(smmu->dev, "ias %lu-bit, oas %lu-bit (features 0x%08x)\n",
>  		 smmu->ias, smmu->oas, smmu->features);
>  	return 0;
> @@ -2645,7 +3055,7 @@ static inline int arm_smmu_device_acpi_probe(struct platform_device *pdev,
>  static int arm_smmu_device_dt_probe(struct platform_device *pdev,
>  				    struct arm_smmu_device *smmu)
>  {
> -	struct device *dev = &pdev->dev;
> +	struct device *dev = pdev;
>  	u32 cells;
>  	int ret = -EINVAL;
>  
> @@ -2658,7 +3068,7 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev,
>  
>  	parse_driver_options(smmu);
>  
> -	if (of_dma_is_coherent(dev->of_node))
> +	if (dt_get_property(dev->of_node, "dma-coherent", NULL))
>  		smmu->features |= ARM_SMMU_FEAT_COHERENCY;
>  
>  	return ret;
> @@ -2672,66 +3082,76 @@ static unsigned long arm_smmu_resource_size(struct arm_smmu_device *smmu)
>  		return SZ_128K;
>  }
>  
> -static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
> -				      resource_size_t size)
> +
> +static void arm_smmu_free_structures(struct arm_smmu_device *smmu)
>  {
> -	struct resource res = {
> -		.flags = IORESOURCE_MEM,
> -		.start = start,
> -		.end = start + size - 1,
> -	};
> +	if (smmu->cmdq.q.base)
> +		xfree(smmu->cmdq.q.base);
> +
> +	if (smmu->evtq.q.base)
> +		xfree(smmu->evtq.q.base);
>  
> -	return devm_ioremap_resource(dev, &res);
> +	if (smmu->priq.q.base)
> +		xfree(smmu->priq.q.base);
> +
> +	if (smmu->strtab_cfg.strtab)
> +		xfree(smmu->strtab_cfg.strtab);
> +
> +	if (smmu->strtab_cfg.l1_desc)
> +		xfree(smmu->strtab_cfg.l1_desc);

From what I can tell we also need to free somewhere
smmu->strtab_cfg->l1_desc->l2ptr allocated by arm_smmu_init_l2_strtab


>  }
>  
>  static int arm_smmu_device_probe(struct platform_device *pdev)
>  {
>  	int irq, ret;
> -	struct resource *res;
> -	resource_size_t ioaddr;
> +	paddr_t ioaddr, iosize;
>  	struct arm_smmu_device *smmu;
> -	struct device *dev = &pdev->dev;
> -	bool bypass;
>  
> -	smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
> +	smmu = xzalloc(struct arm_smmu_device);
>  	if (!smmu) {
> -		dev_err(dev, "failed to allocate arm_smmu_device\n");
> +		dev_err(pdev, "failed to allocate arm_smmu_device\n");
>  		return -ENOMEM;
>  	}
> -	smmu->dev = dev;
> +	smmu->dev = pdev;
>  
> -	if (dev->of_node) {
> +	if (pdev->of_node) {
>  		ret = arm_smmu_device_dt_probe(pdev, smmu);
> +		if (ret)
> +			goto out_free_smmu;
>  	} else {
>  		ret = arm_smmu_device_acpi_probe(pdev, smmu);
>  		if (ret == -ENODEV)

I can see the if condition was already as is from previous patches but
it would be better to do:

if (ret)
    goto out_free_smmu;

It could be done on commit. Also, I am fine either way.


> -			return ret;
> +			goto out_free_smmu;
>  	}
>  
> -	/* Set bypass mode according to firmware probing result */
> -	bypass = !!ret;
> -
>  	/* Base address */
> -	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> -	if (resource_size(res) < arm_smmu_resource_size(smmu)) {
> -		dev_err(dev, "MMIO region too small (%pr)\n", res);
> -		return -EINVAL;
> +	ret = dt_device_get_address(dev_to_dt(pdev), 0, &ioaddr, &iosize);
> +	if (ret)
> +		goto out_free_smmu;
> +
> +	if (iosize < arm_smmu_resource_size(smmu)) {
> +		dev_err(pdev, "MMIO region too small (%lx)\n", iosize);
> +		ret = -EINVAL;
> +		goto out_free_smmu;
>  	}
> -	ioaddr = res->start;
>  
>  	/*
>  	 * Don't map the IMPLEMENTATION DEFINED regions, since they may contain
> -	 * the PMCG registers which are reserved by the PMU driver.
> +	 * the PMCG registers which are optional and currently not supported.
>  	 */
> -	smmu->base = arm_smmu_ioremap(dev, ioaddr, ARM_SMMU_REG_SZ);
> -	if (IS_ERR(smmu->base))
> -		return PTR_ERR(smmu->base);
> +	smmu->base = ioremap_nocache(ioaddr, ARM_SMMU_REG_SZ);
> +	if (IS_ERR(smmu->base)) {
> +		ret = PTR_ERR(smmu->base);
> +		goto out_free_smmu;
> +	}
>  
> -	if (arm_smmu_resource_size(smmu) > SZ_64K) {
> -		smmu->page1 = arm_smmu_ioremap(dev, ioaddr + SZ_64K,
> +	if (iosize > SZ_64K) {
> +		smmu->page1 = ioremap_nocache(ioaddr + SZ_64K,
>  					       ARM_SMMU_REG_SZ);
> -		if (IS_ERR(smmu->page1))
> -			return PTR_ERR(smmu->page1);
> +		if (IS_ERR(smmu->page1)) {
> +			ret = PTR_ERR(smmu->page1);
> +			goto out_free;
> +		}
>  	} else {
>  		smmu->page1 = smmu->base;
>  	}
> @@ -2756,23 +3176,286 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
>  	}
>  	/* Probe the h/w */
>  	ret = arm_smmu_device_hw_probe(smmu);
> -	if (ret)
> -		return ret;
> +	if (ret) {
> +		ret = -ENODEV;
> +		goto out_free;
> +	}
>  
>  	/* Initialise in-memory data structures */
>  	ret = arm_smmu_init_structures(smmu);
>  	if (ret)
> -		return ret;
> +		goto out_free;
>  
>  	/* Reset the device */
> -	ret = arm_smmu_device_reset(smmu, bypass);
> +	ret = arm_smmu_device_reset(smmu);
>  	if (ret)
> -		return ret;
> +		goto out_free;
> +
> +	/*
> +	 * Keep a list of all probed devices. This will be used to query
> +	 * the smmu devices based on the fwnode.
> +	 */
> +	INIT_LIST_HEAD(&smmu->devices);
> +
> +	spin_lock(&arm_smmu_devices_lock);
> +	list_add(&smmu->devices, &arm_smmu_devices);
> +	spin_unlock(&arm_smmu_devices_lock);
>  
>  	return 0;
> +
> +
> +out_free:
> +	arm_smmu_free_structures(smmu);
> +	if (smmu->page1)
> +		iounmap(smmu->page1);
> +	if (smmu->base)
> +		iounmap(smmu->base);
> +
> +out_free_smmu:
> +	xfree(smmu);
> +
> +	return ret;
>  }
>  
> -static const struct of_device_id arm_smmu_of_match[] = {
> +static const struct dt_device_match arm_smmu_of_match[] = {
>  	{ .compatible = "arm,smmu-v3", },
>  	{ },
>  };
> +
> +/* Start of Xen specific code. */
> +static int __must_check arm_smmu_iotlb_flush_all(struct domain *d)
> +{
> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
> +	struct iommu_domain *io_domain;
> +
> +	spin_lock(&xen_domain->lock);
> +
> +	list_for_each_entry(io_domain, &xen_domain->contexts, list) {
> +		/*
> +		 * Only invalidate the context when SMMU is present.
> +		 * This is because the context initialization is delayed
> +		 * until a master has been added.
> +		 */
> +		if (unlikely(!ACCESS_ONCE(to_smmu_domain(io_domain)->smmu)))
> +			continue;
> +
> +		arm_smmu_tlb_inv_context(to_smmu_domain(io_domain));
> +	}
> +
> +	spin_unlock(&xen_domain->lock);
> +
> +	return 0;
> +}
> +
> +static int __must_check arm_smmu_iotlb_flush(struct domain *d, dfn_t dfn,
> +				unsigned long page_count, unsigned int flush_flags)
> +{
> +	return arm_smmu_iotlb_flush_all(d);
> +}
> +
> +static struct arm_smmu_device *arm_smmu_get_by_dev(struct device *dev)
> +{
> +	struct arm_smmu_device *smmu = NULL;
> +
> +	spin_lock(&arm_smmu_devices_lock);
> +
> +	list_for_each_entry(smmu, &arm_smmu_devices, devices) {
> +		if (smmu->dev  == dev) {
> +			spin_unlock(&arm_smmu_devices_lock);
> +			return smmu;
> +		}
> +	}
> +
> +	spin_unlock(&arm_smmu_devices_lock);
> +
> +	return NULL;
> +}
> +
> +static struct iommu_domain *arm_smmu_get_domain(struct domain *d,
> +				struct device *dev)
> +{
> +	struct iommu_domain *io_domain;
> +	struct arm_smmu_domain *smmu_domain;
> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
> +	struct arm_smmu_device *smmu = arm_smmu_get_by_dev(fwspec->iommu_dev);
> +
> +	if (!smmu)
> +		return NULL;
> +
> +	/*
> +	 * Loop through the &xen_domain->contexts to locate a context
> +	 * assigned to this SMMU
> +	 */
> +	list_for_each_entry(io_domain, &xen_domain->contexts, list) {
> +		smmu_domain = to_smmu_domain(io_domain);
> +		if (smmu_domain->smmu == smmu)
> +			return io_domain;
> +	}
> +	return NULL;
> +}
> +
> +static void arm_smmu_destroy_iommu_domain(struct iommu_domain *io_domain)
> +{
> +	list_del(&io_domain->list);
> +	arm_smmu_domain_free(io_domain);
> +}
> +
> +static int arm_smmu_assign_dev(struct domain *d, u8 devfn,
> +		struct device *dev, u32 flag)
> +{
> +	int ret = 0;
> +	struct iommu_domain *io_domain;
> +	struct arm_smmu_domain *smmu_domain;
> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
> +
> +	spin_lock(&xen_domain->lock);
> +
> +	/*
> +	 * Check to see if an iommu_domain already exists for this xen domain
> +	 * under the same SMMU
> +	 */
> +	io_domain = arm_smmu_get_domain(d, dev);
> +	if (!io_domain) {
> +		io_domain = arm_smmu_domain_alloc();
> +		if (!io_domain) {
> +			ret = -ENOMEM;
> +			goto out;
> +		}
> +		smmu_domain = to_smmu_domain(io_domain);
> +		smmu_domain->d = d;
> +
> +		/* Chain the new context to the domain */
> +		list_add(&io_domain->list, &xen_domain->contexts);
> +	}
> +
> +	ret = arm_smmu_attach_dev(io_domain, dev);
> +	if (ret) {
> +		if (io_domain->ref.counter == 0)
> +			arm_smmu_destroy_iommu_domain(io_domain);
> +	} else {
> +		atomic_inc(&io_domain->ref);
> +	}
> +
> +out:
> +	spin_unlock(&xen_domain->lock);
> +	return ret;
> +}
> +
> +static int arm_smmu_deassign_dev(struct domain *d, struct device *dev)
> +{
> +	struct iommu_domain *io_domain = arm_smmu_get_domain(d, dev);
> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
> +	struct arm_smmu_domain *smmu_domain = to_smmu_domain(io_domain);
> +	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
> +
> +	if (!smmu_domain || smmu_domain->d != d) {
> +		dev_err(dev, " not attached to domain %d\n", d->domain_id);
> +		return -ESRCH;
> +	}
> +
> +	spin_lock(&xen_domain->lock);
> +
> +	arm_smmu_detach_dev(master);
> +	atomic_dec(&io_domain->ref);
> +
> +	if (io_domain->ref.counter == 0)
> +		arm_smmu_destroy_iommu_domain(io_domain);
> +
> +	spin_unlock(&xen_domain->lock);
> +
> +	return 0;
> +}
> +
> +static int arm_smmu_reassign_dev(struct domain *s, struct domain *t,
> +				u8 devfn,  struct device *dev)
> +{
> +	int ret = 0;
> +
> +	/* Don't allow remapping on other domain than hwdom */
> +	if (t && t != hardware_domain)
> +		return -EPERM;
> +
> +	if (t == s)
> +		return 0;
> +
> +	ret = arm_smmu_deassign_dev(s, dev);
> +	if (ret)
> +		return ret;
> +
> +	if (t) {
> +		/* No flags are defined for ARM. */
> +		ret = arm_smmu_assign_dev(t, devfn, dev, 0);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int arm_smmu_iommu_xen_domain_init(struct domain *d)
> +{
> +	struct arm_smmu_xen_domain *xen_domain;
> +
> +	xen_domain = xzalloc(struct arm_smmu_xen_domain);
> +	if (!xen_domain)
> +		return -ENOMEM;
> +
> +	spin_lock_init(&xen_domain->lock);
> +	INIT_LIST_HEAD(&xen_domain->contexts);
> +
> +	dom_iommu(d)->arch.priv = xen_domain;
> +	return 0;
> +
> +}
> +
> +static void __hwdom_init arm_smmu_iommu_hwdom_init(struct domain *d)
> +{
> +}
> +
> +static void arm_smmu_iommu_xen_domain_teardown(struct domain *d)
> +{
> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
> +
> +	ASSERT(list_empty(&xen_domain->contexts));
> +	xfree(xen_domain);
> +}
> +
> +static const struct iommu_ops arm_smmu_iommu_ops = {
> +	.init		= arm_smmu_iommu_xen_domain_init,
> +	.hwdom_init		= arm_smmu_iommu_hwdom_init,
> +	.teardown		= arm_smmu_iommu_xen_domain_teardown,
> +	.iotlb_flush		= arm_smmu_iotlb_flush,
> +	.iotlb_flush_all	= arm_smmu_iotlb_flush_all,
> +	.assign_device		= arm_smmu_assign_dev,
> +	.reassign_device	= arm_smmu_reassign_dev,
> +	.map_page		= arm_iommu_map_page,
> +	.unmap_page		= arm_iommu_unmap_page,
> +	.dt_xlate		= arm_smmu_dt_xlate,
> +	.add_device		= arm_smmu_add_device,
> +};
> +
> +static __init int arm_smmu_dt_init(struct dt_device_node *dev,
> +				const void *data)
> +{
> +	int rc;
> +
> +	/*
> +	 * Even if the device can't be initialized, we don't want to
> +	 * give the SMMU device to dom0.
> +	 */
> +	dt_device_set_used_by(dev, DOMID_XEN);
> +
> +	rc = arm_smmu_device_probe(dt_to_dev(dev));
> +	if (rc)
> +		return rc;
> +
> +	iommu_set_ops(&arm_smmu_iommu_ops);
> +
> +	return 0;
> +}
> +
> +DT_DEVICE_START(smmuv3, "ARM SMMU V3", DEVICE_IOMMU)
> +.dt_match = arm_smmu_of_match,
> +.init = arm_smmu_dt_init,
> +DT_DEVICE_END
> -- 
> 2.17.1
> 


^ permalink raw reply	[flat|nested] 24+ messages in thread

* Re: [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver
  2021-01-20 14:52 ` [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver Rahul Singh
  2021-01-20 15:35   ` Bertrand Marquis
  2021-01-20 20:31   ` Stefano Stabellini
@ 2021-01-20 21:33   ` Oleksandr
  2021-01-21 17:18     ` Rahul Singh
  2 siblings, 1 reply; 24+ messages in thread
From: Oleksandr @ 2021-01-20 21:33 UTC (permalink / raw)
  To: Rahul Singh
  Cc: xen-devel, bertrand.marquis, Andrew Cooper, George Dunlap,
	Ian Jackson, Jan Beulich, Julien Grall, Stefano Stabellini,
	Wei Liu, Paul Durrant, Volodymyr Babchuk


On 20.01.21 16:52, Rahul Singh wrote:

Hi Rahul

> Add support for ARM architected SMMUv3 implementation. It is based on
> the Linux SMMUv3 driver.
>
> Driver is currently supported as Tech Preview.
>
> Major differences with regard to Linux driver are as follows:
> 2. Only Stage-2 translation is supported as compared to the Linux driver
>     that supports both Stage-1 and Stage-2 translations.
> 3. Use P2M  page table instead of creating one as SMMUv3 has the
>     capability to share the page tables with the CPU.
> 4. Tasklets are used in place of threaded IRQ's in Linux for event queue
>     and priority queue IRQ handling.
> 5. Latest version of the Linux SMMUv3 code implements the commands queue
>     access functions based on atomic operations implemented in Linux.
>     Atomic functions used by the commands queue access functions are not
>     implemented in XEN therefore we decided to port the earlier version
>     of the code. Atomic operations are introduced to fix the bottleneck
>     of the SMMU command queue insertion operation. A new algorithm for
>     inserting commands into the queue is introduced, which is lock-free
>     on the fast-path.
>     Consequence of reverting the patch is that the command queue
>     insertion will be slow for large systems as spinlock will be used to
>     serializes accesses from all CPUs to the single queue supported by
>     the hardware. Once the proper atomic operations will be available in
>     XEN the driver can be updated.
> 6. Spin lock is used in place of mutex when attaching a device to the
>     SMMU, as there is no blocking locks implementation available in XEN.
>     This might introduce latency in XEN. Need to investigate before
>     driver is out for tech preview.
> 7. PCI ATS functionality is not supported, as there is no support
>     available in XEN to test the functionality. Code is not tested and
>     compiled. Code is guarded by the flag CONFIG_PCI_ATS.
> 8. MSI interrupts are not supported as there is no support available in
>     XEN to request MSI interrupts. Code is not tested and compiled. Code
>     is guarded by the flag CONFIG_MSI.
>
> Signed-off-by: Rahul Singh <rahul.singh@arm.com>
> ---
> Changes since v2:
> - added return statement for readx_poll_timeout function.
> - remove iommu_get_dma_cookie and iommu_put_dma_cookie.
> - remove struct arm_smmu_xen_device as not required.
> - move dt_property_match_string to device_tree.c file.
> - replace arm_smmu_*_thread to arm_smmu_*_tasklet to avoid confusion.
> - use ARM_SMMU_REG_SZ as size when map memory to XEN.
> - remove bypass keyword to make sure when device-tree probe is failed we
>    are reporting error and not continuing to configure SMMU in bypass
>    mode.
> - fixed minor comments.
> Changes since v3:
> - Fixed typo for CONFIG_MSI
> - Added back the mutex code
> - Rebase the patch on top of newly added WARN_ON().
> - Remove the direct read of register VTCR_EL2.
> - Fixed minor comments.
> Changes since v4:
> - Replace the ffsll() with ffs64() function.
> - Add code to free resources when probe failed.

Thank you for addressing, patch looks ok to me, just one small remark below:


> +
> +static void __hwdom_init arm_smmu_iommu_hwdom_init(struct domain *d)
> +{
> +}

We discussed in V4 about adding some code here which all IOMMUs on Arm 
already have, copy it below for the convenience:


      /* Set to false options not supported on ARM. */
      if ( iommu_hwdom_inclusive )
          printk(XENLOG_WARNING
          "map-inclusive dom0-iommu option is not supported on ARM\n");
      iommu_hwdom_inclusive = false;
      if ( iommu_hwdom_reserved == 1 )
          printk(XENLOG_WARNING
          "map-reserved dom0-iommu option is not supported on ARM\n");
      iommu_hwdom_reserved = 0;

      arch_iommu_hwdom_init(d);


Also we discussed about possibility to fold the part of code (which 
disables unsupported options) in arch_iommu_hwdom_init() to avoid 
duplication as a follow-up.
At least, I expected to see arch_iommu_hwdom_init() to be called by 
arm_smmu_iommu_hwdom_init() it current patch... Please note, this is 
*not* a request for change immediately,
I think, driver is functional even without this code (hopefully 
arch_iommu_hwdom_init is empty now, etc).  But, if you happen to do V6 
or probably it could be done on commit ...


> +
> +static void arm_smmu_iommu_xen_domain_teardown(struct domain *d)
> +{
> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
> +
> +	ASSERT(list_empty(&xen_domain->contexts));
> +	xfree(xen_domain);
> +}
> +
> +static const struct iommu_ops arm_smmu_iommu_ops = {
> +	.init		= arm_smmu_iommu_xen_domain_init,
> +	.hwdom_init		= arm_smmu_iommu_hwdom_init,
> +	.teardown		= arm_smmu_iommu_xen_domain_teardown,
> +	.iotlb_flush		= arm_smmu_iotlb_flush,
> +	.iotlb_flush_all	= arm_smmu_iotlb_flush_all,
> +	.assign_device		= arm_smmu_assign_dev,
> +	.reassign_device	= arm_smmu_reassign_dev,
> +	.map_page		= arm_iommu_map_page,
> +	.unmap_page		= arm_iommu_unmap_page,
> +	.dt_xlate		= arm_smmu_dt_xlate,
> +	.add_device		= arm_smmu_add_device,
> +};
> +
> +static __init int arm_smmu_dt_init(struct dt_device_node *dev,
> +				const void *data)
> +{
> +	int rc;
> +
> +	/*
> +	 * Even if the device can't be initialized, we don't want to
> +	 * give the SMMU device to dom0.
> +	 */
> +	dt_device_set_used_by(dev, DOMID_XEN);
> +
> +	rc = arm_smmu_device_probe(dt_to_dev(dev));
> +	if (rc)
> +		return rc;
> +
> +	iommu_set_ops(&arm_smmu_iommu_ops);
> +
> +	return 0;
> +}
> +
> +DT_DEVICE_START(smmuv3, "ARM SMMU V3", DEVICE_IOMMU)
> +.dt_match = arm_smmu_of_match,
> +.init = arm_smmu_dt_init,
> +DT_DEVICE_END

-- 
Regards,

Oleksandr Tyshchenko



^ permalink raw reply	[flat|nested] 24+ messages in thread

* Re: [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver
  2021-01-20 20:31   ` Stefano Stabellini
@ 2021-01-21 17:10     ` Rahul Singh
  2021-01-21 18:43       ` Julien Grall
  0 siblings, 1 reply; 24+ messages in thread
From: Rahul Singh @ 2021-01-21 17:10 UTC (permalink / raw)
  To: Stefano Stabellini
  Cc: xen-devel, Bertrand Marquis, Andrew Cooper, George Dunlap,
	Ian Jackson, Jan Beulich, Julien Grall, Wei Liu, Paul Durrant,
	Volodymyr Babchuk

Hello Stefano,

> On 20 Jan 2021, at 8:31 pm, Stefano Stabellini <sstabellini@kernel.org> wrote:
> 
> On Wed, 20 Jan 2021, Rahul Singh wrote:
>> Add support for ARM architected SMMUv3 implementation. It is based on
>> the Linux SMMUv3 driver.
>> 
>> Driver is currently supported as Tech Preview.
>> 
>> Major differences with regard to Linux driver are as follows:
>> 2. Only Stage-2 translation is supported as compared to the Linux driver
>>   that supports both Stage-1 and Stage-2 translations.
>> 3. Use P2M  page table instead of creating one as SMMUv3 has the
>>   capability to share the page tables with the CPU.
>> 4. Tasklets are used in place of threaded IRQ's in Linux for event queue
>>   and priority queue IRQ handling.
>> 5. Latest version of the Linux SMMUv3 code implements the commands queue
>>   access functions based on atomic operations implemented in Linux.
>>   Atomic functions used by the commands queue access functions are not
>>   implemented in XEN therefore we decided to port the earlier version
>>   of the code. Atomic operations are introduced to fix the bottleneck
>>   of the SMMU command queue insertion operation. A new algorithm for
>>   inserting commands into the queue is introduced, which is lock-free
>>   on the fast-path.
>>   Consequence of reverting the patch is that the command queue
>>   insertion will be slow for large systems as spinlock will be used to
>>   serializes accesses from all CPUs to the single queue supported by
>>   the hardware. Once the proper atomic operations will be available in
>>   XEN the driver can be updated.
>> 6. Spin lock is used in place of mutex when attaching a device to the
>>   SMMU, as there is no blocking locks implementation available in XEN.
>>   This might introduce latency in XEN. Need to investigate before
>>   driver is out for tech preview.
>> 7. PCI ATS functionality is not supported, as there is no support
>>   available in XEN to test the functionality. Code is not tested and
>>   compiled. Code is guarded by the flag CONFIG_PCI_ATS.
>> 8. MSI interrupts are not supported as there is no support available in
>>   XEN to request MSI interrupts. Code is not tested and compiled. Code
>>   is guarded by the flag CONFIG_MSI.
>> 
>> Signed-off-by: Rahul Singh <rahul.singh@arm.com>
>> ---
>> Changes since v2:
>> - added return statement for readx_poll_timeout function.
>> - remove iommu_get_dma_cookie and iommu_put_dma_cookie.
>> - remove struct arm_smmu_xen_device as not required.
>> - move dt_property_match_string to device_tree.c file.
>> - replace arm_smmu_*_thread to arm_smmu_*_tasklet to avoid confusion.
>> - use ARM_SMMU_REG_SZ as size when map memory to XEN.
>> - remove bypass keyword to make sure when device-tree probe is failed we
>>  are reporting error and not continuing to configure SMMU in bypass
>>  mode.
>> - fixed minor comments.
>> Changes since v3:
>> - Fixed typo for CONFIG_MSI
>> - Added back the mutex code
>> - Rebase the patch on top of newly added WARN_ON().
>> - Remove the direct read of register VTCR_EL2.
>> - Fixed minor comments.
>> Changes since v4:
>> - Replace the ffsll() with ffs64() function.
>> - Add code to free resources when probe failed.
>> ---
>> ---
>> MAINTAINERS                           |   6 +
>> SUPPORT.md                            |   1 +
>> xen/drivers/passthrough/Kconfig       |  11 +
>> xen/drivers/passthrough/arm/Makefile  |   1 +
>> xen/drivers/passthrough/arm/smmu-v3.c | 939 ++++++++++++++++++++++----
>> 5 files changed, 830 insertions(+), 128 deletions(-)
>> 
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index 5079b834c2..14240e8e1e 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -249,6 +249,12 @@ F:	xen/include/asm-arm/
>> F:	xen/include/public/arch-arm/
>> F:	xen/include/public/arch-arm.h
>> 
>> +ARM SMMUv3
>> +M:	Bertrand Marquis <bertrand.marquis@arm.com>
>> +M:	Rahul Singh <rahul.singh@arm.com>
>> +S:	Supported
>> +F:	xen/drivers/passthrough/arm/smmu-v3.c
>> +
>> Change Log
>> M:	Paul Durrant <paul@xen.org>
>> R:	Community Manager <community.manager@xenproject.org>
>> diff --git a/SUPPORT.md b/SUPPORT.md
>> index ab02aca5f4..5ee3c8651a 100644
>> --- a/SUPPORT.md
>> +++ b/SUPPORT.md
>> @@ -67,6 +67,7 @@ For the Cortex A57 r0p0 - r1p1, see Errata 832075.
>>     Status, Intel VT-d: Supported
>>     Status, ARM SMMUv1: Supported, not security supported
>>     Status, ARM SMMUv2: Supported, not security supported
>> +    Status, ARM SMMUv3: Tech Preview
>>     Status, Renesas IPMMU-VMSA: Supported, not security supported
>> 
>> ### ARM/GICv3 ITS
>> diff --git a/xen/drivers/passthrough/Kconfig b/xen/drivers/passthrough/Kconfig
>> index 0036007ec4..341ba92b30 100644
>> --- a/xen/drivers/passthrough/Kconfig
>> +++ b/xen/drivers/passthrough/Kconfig
>> @@ -13,6 +13,17 @@ config ARM_SMMU
>> 	  Say Y here if your SoC includes an IOMMU device implementing the
>> 	  ARM SMMU architecture.
>> 
>> +config ARM_SMMU_V3
>> +	bool "ARM Ltd. System MMU Version 3 (SMMUv3) Support" if EXPERT
>> +	depends on ARM_64
>> +	---help---
>> +	 Support for implementations of the ARM System MMU architecture
>> +	 version 3. Driver is in experimental stage and should not be used in
>> +	 production.
>> +
>> +	 Say Y here if your system includes an IOMMU device implementing
>> +	 the ARM SMMUv3 architecture.
>> +
>> config IPMMU_VMSA
>> 	bool "Renesas IPMMU-VMSA found in R-Car Gen3 SoCs"
>> 	depends on ARM_64
>> diff --git a/xen/drivers/passthrough/arm/Makefile b/xen/drivers/passthrough/arm/Makefile
>> index fcd918ea3e..c5fb3b58a5 100644
>> --- a/xen/drivers/passthrough/arm/Makefile
>> +++ b/xen/drivers/passthrough/arm/Makefile
>> @@ -1,3 +1,4 @@
>> obj-y += iommu.o iommu_helpers.o iommu_fwspec.o
>> obj-$(CONFIG_ARM_SMMU) += smmu.o
>> obj-$(CONFIG_IPMMU_VMSA) += ipmmu-vmsa.o
>> +obj-$(CONFIG_ARM_SMMU_V3) += smmu-v3.o
>> diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
>> index 2dfadc6a65..dd0540bb5f 100644
>> --- a/xen/drivers/passthrough/arm/smmu-v3.c
>> +++ b/xen/drivers/passthrough/arm/smmu-v3.c
>> @@ -2,37 +2,263 @@
>> /*
>>  * IOMMU API for ARM architected SMMUv3 implementations.
>>  *
>> + * Based on Linux's SMMUv3 driver:
>> + *    drivers/iommu/arm-smmu-v3.c
>> + *    commit: ab435ce49bd1d02e33dfec24f76955dc1196970b
>> + * and Xen's SMMU driver:
>> + *    xen/drivers/passthrough/arm/smmu.c
>> + *
>> + * Major differences with regard to Linux driver are as follows:
>> + *  1. Driver is currently supported as Tech Preview.
>> + *  2. Only Stage-2 translation is supported as compared to the Linux driver
>> + *     that supports both Stage-1 and Stage-2 translations.
>> + *  3. Use P2M  page table instead of creating one as SMMUv3 has the
>> + *     capability to share the page tables with the CPU.
>> + *  4. Tasklets are used in place of threaded IRQ's in Linux for event queue
>> + *     and priority queue IRQ handling.
>> + *  5. Latest version of the Linux SMMUv3 code implements the commands queue
>> + *     access functions based on atomic operations implemented in Linux.
>> + *     Atomic functions used by the commands queue access functions are not
>> + *     implemented in XEN therefore we decided to port the earlier version
>> + *     of the code. Atomic operations are introduced to fix the bottleneck of
>> + *     the SMMU command queue insertion operation. A new algorithm for
>> + *     inserting commands into the queue is introduced, which is
>> + *     lock-free on the fast-path.
>> + *     Consequence of reverting the patch is that the command queue insertion
>> + *     will be slow for large systems as spinlock will be used to serializes
>> + *     accesses from all CPUs to the single queue supported by the hardware.
>> + *     Once the proper atomic operations will be available in XEN the driver
>> + *     can be updated.
>> + *  6. Spin lock is used in place of Mutex when attaching a device to the SMMU,
>> + *     as there is no blocking locks implementation available in XEN.This might
>> + *     introduce latency in XEN. Need to investigate before driver is out for
>> + *     Tech Preview.
>> + *  7. PCI ATS functionality is not supported, as there is no support available
>> + *     in XEN to test the functionality. Code is not tested and compiled. Code
>> + *     is guarded by the flag CONFIG_PCI_ATS.
>> + *  8. MSI interrupts are not supported as there is no support available
>> + *     in XEN to request MSI interrupts. Code is not tested and compiled. Code
>> + *     is guarded by the flag CONFIG_MSI.
>> + *
>> + * Following functionality should be supported before driver is out for tech
>> + * preview
>> + *
>> + *  1. Investigate the timing analysis of using spin lock in place of mutex
>> + *     when attaching devices to SMMU.
>> + *  2. Merged the latest Linux SMMUv3 driver code once atomic operation is
>> + *     available in XEN.
>> + *  3. PCI ATS and MSI interrupts should be supported.
>> + *  4. Investigate side-effect of using tasklet in place of threaded IRQ and
>> + *     fix if any.
>> + *
>>  * Copyright (C) 2015 ARM Limited
>>  *
>>  * Author: Will Deacon <will.deacon@arm.com>
>>  *
>> - * This driver is powered by bad coffee and bombay mix.
>> + * Copyright (C) 2020 Arm Ltd
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> + * GNU General Public License for more details.
>> + *
>> + * You should have received a copy of the GNU General Public License
>> + * along with this program.  If not, see <http://www.gnu.org/licenses/>.
>> + *
>>  */
>> 
>> -#include <linux/acpi.h>
>> -#include <linux/acpi_iort.h>
>> -#include <linux/bitfield.h>
>> -#include <linux/bitops.h>
>> -#include <linux/crash_dump.h>
>> -#include <linux/delay.h>
>> -#include <linux/dma-iommu.h>
>> -#include <linux/err.h>
>> -#include <linux/interrupt.h>
>> -#include <linux/io-pgtable.h>
>> -#include <linux/iommu.h>
>> -#include <linux/iopoll.h>
>> -#include <linux/module.h>
>> -#include <linux/msi.h>
>> -#include <linux/of.h>
>> -#include <linux/of_address.h>
>> -#include <linux/of_iommu.h>
>> -#include <linux/of_platform.h>
>> -#include <linux/pci.h>
>> -#include <linux/pci-ats.h>
>> -#include <linux/platform_device.h>
>> -
>> -#include <linux/amba/bus.h>
>> +#include <xen/acpi.h>
>> +#include <xen/config.h>
>> +#include <xen/delay.h>
>> +#include <xen/errno.h>
>> +#include <xen/err.h>
>> +#include <xen/irq.h>
>> +#include <xen/lib.h>
>> +#include <xen/list.h>
>> +#include <xen/mm.h>
>> +#include <xen/rbtree.h>
>> +#include <xen/sched.h>
>> +#include <xen/sizes.h>
>> +#include <xen/vmap.h>
>> +#include <asm/atomic.h>
>> +#include <asm/device.h>
>> +#include <asm/io.h>
>> +#include <asm/iommu_fwspec.h>
>> +#include <asm/platform.h>
>> +
>> +
>> +#define ARM_SMMU_VTCR_SH_IS		3
>> +#define ARM_SMMU_VTCR_RGN_WBWA		1
>> +#define ARM_SMMU_VTCR_TG0_4K		0
>> +#define ARM_SMMU_VTCR_PS_32_BIT		0x0ULL
>> +#define ARM_SMMU_VTCR_PS_36_BIT		0x1ULL
>> +#define ARM_SMMU_VTCR_PS_40_BIT		0x2ULL
>> +#define ARM_SMMU_VTCR_PS_42_BIT		0x3ULL
>> +#define ARM_SMMU_VTCR_PS_44_BIT		0x4ULL
>> +#define ARM_SMMU_VTCR_PS_48_BIT		0x5ULL
>> +#define ARM_SMMU_VTCR_PS_52_BIT		0x6ULL
>> +
>> +/* Linux compatibility functions. */
>> +typedef paddr_t		dma_addr_t;
>> +typedef paddr_t		phys_addr_t;
>> +typedef unsigned int		gfp_t;
>> +
>> +#define platform_device		device
>> +
>> +#define GFP_KERNEL		0
>> +
>> +/* Alias to Xen lock functions */
>> +#define mutex spinlock
>> +#define mutex_init spin_lock_init
>> +#define mutex_lock spin_lock
>> +#define mutex_unlock spin_unlock
>> +
>> +/* Device logger functions */
>> +#define dev_name(dev)	dt_node_full_name(dev->of_node)
>> +#define dev_dbg(dev, fmt, ...)			\
>> +	printk(XENLOG_DEBUG "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
>> +#define dev_notice(dev, fmt, ...)		\
>> +	printk(XENLOG_INFO "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
>> +#define dev_warn(dev, fmt, ...)			\
>> +	printk(XENLOG_WARNING "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
>> +#define dev_err(dev, fmt, ...)			\
>> +	printk(XENLOG_ERR "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
>> +#define dev_info(dev, fmt, ...)			\
>> +	printk(XENLOG_INFO "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
>> +#define dev_err_ratelimited(dev, fmt, ...)			\
>> +	printk(XENLOG_ERR "SMMUv3: %s: " fmt, dev_name(dev), ## __VA_ARGS__)
>> +
>> +/*
>> + * Periodically poll an address and wait between reads in us until a
>> + * condition is met or a timeout occurs.
>> + *
>> + * @return: 0 when cond met, -ETIMEDOUT upon timeout
>> + */
>> +#define readx_poll_timeout(op, addr, val, cond, sleep_us, timeout_us) \
>> +({ \
>> +	s_time_t deadline = NOW() + MICROSECS(timeout_us); \
>> +	for (;;) { \
>> +		(val) = op(addr); \
>> +		if (cond) \
>> +			break; \
>> +		if (NOW() > deadline) { \
>> +			(val) = op(addr); \
>> +			break; \
>> +		} \
>> +		udelay(sleep_us); \
>> +	} \
>> +	(cond) ? 0 : -ETIMEDOUT; \
>> +})
>> +
>> +#define readl_relaxed_poll_timeout(addr, val, cond, delay_us, timeout_us)	\
>> +	readx_poll_timeout(readl_relaxed, addr, val, cond, delay_us, timeout_us)
>> +
>> +#define FIELD_PREP(_mask, _val)			\
>> +	(((typeof(_mask))(_val) << (ffs64(_mask) - 1)) & (_mask))
>> +
>> +#define FIELD_GET(_mask, _reg)			\
>> +	((typeof(_mask))(((_reg) & (_mask)) >> (ffs64(_mask) - 1)))
>> +
>> +/*
>> + * Helpers for DMA allocation. Just the function name is reused for
>> + * porting code, these allocation are not managed allocations
>> + */
>> +static void *dmam_alloc_coherent(struct device *dev, size_t size,
>> +				paddr_t *dma_handle, gfp_t gfp)
>> +{
>> +	void *vaddr;
>> +	unsigned long alignment = size;
>> +
>> +	/*
>> +	 * _xzalloc requires that the (align & (align -1)) = 0. Most of the
>> +	 * allocations in SMMU code should send the right value for size. In
>> +	 * case this is not true print a warning and align to the size of a
>> +	 * (void *)
>> +	 */
>> +	if (size & (size - 1)) {
>> +		printk(XENLOG_WARNING "SMMUv3: Fixing alignment for the DMA buffer\n");
>> +		alignment = sizeof(void *);
>> +	}
>> +
>> +	vaddr = _xzalloc(size, alignment);
>> +	if (!vaddr) {
>> +		printk(XENLOG_ERR "SMMUv3: DMA allocation failed\n");
>> +		return NULL;
>> +	}
>> +
>> +	*dma_handle = virt_to_maddr(vaddr);
>> +
>> +	return vaddr;
>> +}
>> +
>> +
>> +/* Xen specific code. */
>> +struct iommu_domain {
>> +	/* Runtime SMMU configuration for this iommu_domain */
>> +	atomic_t		ref;
>> +	/*
>> +	 * Used to link iommu_domain contexts for a same domain.
>> +	 * There is at least one per-SMMU to used by the domain.
>> +	 */
>> +	struct list_head		list;
>> +};
>> +
>> +/* Describes information required for a Xen domain */
>> +struct arm_smmu_xen_domain {
>> +	spinlock_t		lock;
>> +
>> +	/* List of iommu domains associated to this domain */
>> +	struct list_head	contexts;
>> +};
>> +
>> +
>> +/* Keep a list of devices associated with this driver */
>> +static DEFINE_SPINLOCK(arm_smmu_devices_lock);
>> +static LIST_HEAD(arm_smmu_devices);
>> +
>> +static inline void *dev_iommu_priv_get(struct device *dev)
>> +{
>> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
>> +
>> +	return fwspec && fwspec->iommu_priv ? fwspec->iommu_priv : NULL;
>> +}
>> +
>> +static inline void dev_iommu_priv_set(struct device *dev, void *priv)
>> +{
>> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
>> +
>> +	fwspec->iommu_priv = priv;
>> +}
>> +
>> +static int platform_get_irq_byname_optional(struct device *dev,
>> +				const char *name)
>> +{
>> +	int index, ret;
>> +	struct dt_device_node *np  = dev_to_dt(dev);
>> +
>> +	if (unlikely(!name))
>> +		return -EINVAL;
>> +
>> +	index = dt_property_match_string(np, "interrupt-names", name);
>> +	if (index < 0) {
>> +		dev_info(dev, "IRQ %s not found\n", name);
>> +		return index;
>> +	}
>> +
>> +	ret = platform_get_irq(np, index);
>> +	if (ret < 0) {
>> +		dev_err(dev, "failed to get irq index %d\n", index);
>> +		return -ENODEV;
>> +	}
>> +
>> +	return ret;
>> +}
>> 
>> +/* Start of Linux SMMUv3 code */
>> /* MMIO registers */
>> #define ARM_SMMU_IDR0			0x0
>> #define IDR0_ST_LVL			GENMASK(28, 27)
>> @@ -402,6 +628,7 @@ enum pri_resp {
>> 	PRI_RESP_SUCC = 2,
>> };
>> 
>> +#ifdef CONFIG_MSI
>> enum arm_smmu_msi_index {
>> 	EVTQ_MSI_INDEX,
>> 	GERROR_MSI_INDEX,
>> @@ -426,6 +653,7 @@ static phys_addr_t arm_smmu_msi_cfg[ARM_SMMU_MAX_MSIS][3] = {
>> 		ARM_SMMU_PRIQ_IRQ_CFG2,
>> 	},
>> };
>> +#endif /* CONFIG_MSI */
>> 
>> struct arm_smmu_cmdq_ent {
>> 	/* Common fields */
>> @@ -613,8 +841,13 @@ struct arm_smmu_device {
>> 		u64			padding;
>> 	};
>> 
>> -	/* IOMMU core code handle */
>> -	struct iommu_device		iommu;
>> +	/* Need to keep a list of SMMU devices */
>> +	struct list_head		devices;
>> +
>> +	/* Tasklets for handling evts/faults and pci page request IRQs*/
>> +	struct tasklet		evtq_irq_tasklet;
>> +	struct tasklet		priq_irq_tasklet;
>> +	struct tasklet		combined_irq_tasklet;
>> };
>> 
>> /* SMMU private data for each master */
>> @@ -646,6 +879,9 @@ struct arm_smmu_domain {
>> 	enum arm_smmu_domain_stage	stage;
>> 	struct arm_smmu_s2_cfg	s2_cfg;
>> 
>> +	/* Xen domain associated with this SMMU domain */
>> +	struct domain		*d;
>> +
>> 	struct iommu_domain		domain;
>> 
>> 	struct list_head		devices;
>> @@ -984,6 +1220,7 @@ static void arm_smmu_cmdq_issue_cmd(struct arm_smmu_device *smmu,
>> 	spin_unlock_irqrestore(&smmu->cmdq.lock, flags);
>> }
>> 
>> +#ifdef CONFIG_MSI
>> /*
>>  * The difference between val and sync_idx is bounded by the maximum size of
>>  * a queue at 2^20 entries, so 32 bits is plenty for wrap-safe arithmetic.
>> @@ -1027,6 +1264,13 @@ static int __arm_smmu_cmdq_issue_sync_msi(struct arm_smmu_device *smmu)
>> 
>> 	return __arm_smmu_sync_poll_msi(smmu, ent.sync.msidata);
>> }
>> +#else
>> +static inline int __arm_smmu_cmdq_issue_sync_msi(struct arm_smmu_device *smmu)
>> +{
>> +	return 0;
>> +}
>> +#endif /* CONFIG_MSI */
>> +
>> 
>> static int __arm_smmu_cmdq_issue_sync(struct arm_smmu_device *smmu)
>> {
>> @@ -1069,7 +1313,7 @@ arm_smmu_write_strtab_l1_desc(__le64 *dst, struct arm_smmu_strtab_l1_desc *desc)
>> 	val |= desc->l2ptr_dma & STRTAB_L1_DESC_L2PTR_MASK;
>> 
>> 	/* See comment in arm_smmu_write_ctx_desc() */
>> -	WRITE_ONCE(*dst, cpu_to_le64(val));
>> +	write_atomic(dst, cpu_to_le64(val));
>> }
>> 
>> static void arm_smmu_sync_ste_for_sid(struct arm_smmu_device *smmu, u32 sid)
>> @@ -1184,7 +1428,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
>> 						 STRTAB_STE_1_EATS_TRANS));
>> 
>> 	arm_smmu_sync_ste_for_sid(smmu, sid);
>> -	WRITE_ONCE(dst[0], cpu_to_le64(val));
>> +	write_atomic(&dst[0], cpu_to_le64(val));
>> 	arm_smmu_sync_ste_for_sid(smmu, sid);
>> 
>> 	/* It's likely that we'll want to use the new STE soon */
>> @@ -1231,7 +1475,7 @@ static int arm_smmu_init_l2_strtab(struct arm_smmu_device *smmu, u32 sid)
>> }
>> 
>> /* IRQ and event handlers */
>> -static irqreturn_t arm_smmu_evtq_thread(int irq, void *dev)
>> +static void arm_smmu_evtq_tasklet(void *dev)
>> {
>> 	int i;
>> 	struct arm_smmu_device *smmu = dev;
>> @@ -1261,7 +1505,6 @@ static irqreturn_t arm_smmu_evtq_thread(int irq, void *dev)
>> 	/* Sync our overflow flag, as we believe we're up to speed */
>> 	llq->cons = Q_OVF(llq->prod) | Q_WRP(llq, llq->cons) |
>> 		    Q_IDX(llq, llq->cons);
>> -	return IRQ_HANDLED;
>> }
>> 
>> static void arm_smmu_handle_ppr(struct arm_smmu_device *smmu, u64 *evt)
>> @@ -1302,7 +1545,7 @@ static void arm_smmu_handle_ppr(struct arm_smmu_device *smmu, u64 *evt)
>> 	}
>> }
>> 
>> -static irqreturn_t arm_smmu_priq_thread(int irq, void *dev)
>> +static void arm_smmu_priq_tasklet(void *dev)
>> {
>> 	struct arm_smmu_device *smmu = dev;
>> 	struct arm_smmu_queue *q = &smmu->priq.q;
>> @@ -1321,12 +1564,12 @@ static irqreturn_t arm_smmu_priq_thread(int irq, void *dev)
>> 	llq->cons = Q_OVF(llq->prod) | Q_WRP(llq, llq->cons) |
>> 		      Q_IDX(llq, llq->cons);
>> 	queue_sync_cons_out(q);
>> -	return IRQ_HANDLED;
>> }
>> 
>> static int arm_smmu_device_disable(struct arm_smmu_device *smmu);
>> 
>> -static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
>> +static void arm_smmu_gerror_handler(int irq, void *dev,
>> +				struct cpu_user_regs *regs)
>> {
>> 	u32 gerror, gerrorn, active;
>> 	struct arm_smmu_device *smmu = dev;
>> @@ -1336,7 +1579,7 @@ static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
>> 
>> 	active = gerror ^ gerrorn;
>> 	if (!(active & GERROR_ERR_MASK))
>> -		return IRQ_NONE; /* No errors pending */
>> +		return; /* No errors pending */
>> 
>> 	dev_warn(smmu->dev,
>> 		 "unexpected global error reported (0x%08x), this could be serious\n",
>> @@ -1369,26 +1612,44 @@ static irqreturn_t arm_smmu_gerror_handler(int irq, void *dev)
>> 		arm_smmu_cmdq_skip_err(smmu);
>> 
>> 	writel(gerror, smmu->base + ARM_SMMU_GERRORN);
>> -	return IRQ_HANDLED;
>> }
>> 
>> -static irqreturn_t arm_smmu_combined_irq_thread(int irq, void *dev)
>> +static void arm_smmu_combined_irq_handler(int irq, void *dev,
>> +				struct cpu_user_regs *regs)
>> {
>> 	struct arm_smmu_device *smmu = dev;
>> 
>> -	arm_smmu_evtq_thread(irq, dev);
>> +	arm_smmu_gerror_handler(irq, dev, regs);
>> +
>> +	tasklet_schedule(&(smmu->combined_irq_tasklet));
>> +}
>> +
>> +static void arm_smmu_combined_irq_tasklet(void *dev)
>> +{
>> +	struct arm_smmu_device *smmu = dev;
>> +
>> +	arm_smmu_evtq_tasklet(dev);
>> 	if (smmu->features & ARM_SMMU_FEAT_PRI)
>> -		arm_smmu_priq_thread(irq, dev);
>> +		arm_smmu_priq_tasklet(dev);
>> +}
>> +
>> +static void arm_smmu_evtq_irq_tasklet(int irq, void *dev,
>> +				struct cpu_user_regs *regs)
>> +{
>> +	struct arm_smmu_device *smmu = dev;
>> 
>> -	return IRQ_HANDLED;
>> +	tasklet_schedule(&(smmu->evtq_irq_tasklet));
>> }
>> 
>> -static irqreturn_t arm_smmu_combined_irq_handler(int irq, void *dev)
>> +static void arm_smmu_priq_irq_tasklet(int irq, void *dev,
>> +				struct cpu_user_regs *regs)
>> {
>> -	arm_smmu_gerror_handler(irq, dev);
>> -	return IRQ_WAKE_THREAD;
>> +	struct arm_smmu_device *smmu = dev;
>> +
>> +	tasklet_schedule(&(smmu->priq_irq_tasklet));
>> }
>> 
>> +#ifdef CONFIG_PCI_ATS
>> static void
>> arm_smmu_atc_inv_to_cmd(int ssid, unsigned long iova, size_t size,
>> 			struct arm_smmu_cmdq_ent *cmd)
>> @@ -1495,6 +1756,7 @@ static int arm_smmu_atc_inv_domain(struct arm_smmu_domain *smmu_domain,
>> 
>> 	return ret ? -ETIMEDOUT : 0;
>> }
>> +#endif /* CONFIG_PCI_ATS */
>> 
>> static void arm_smmu_tlb_inv_context(void *cookie)
>> {
>> @@ -1525,7 +1787,7 @@ static struct iommu_domain *arm_smmu_domain_alloc(void)
>> 	 * We can't really do anything meaningful until we've added a
>> 	 * master.
>> 	 */
>> -	smmu_domain = kzalloc(sizeof(*smmu_domain), GFP_KERNEL);
>> +	smmu_domain = xzalloc(struct arm_smmu_domain);
>> 	if (!smmu_domain)
>> 		return NULL;
>> 
>> @@ -1563,7 +1825,7 @@ static void arm_smmu_domain_free(struct iommu_domain *domain)
>> 	if (cfg->vmid)
>> 		arm_smmu_bitmap_free(smmu->vmid_map, cfg->vmid);
>> 
>> -	kfree(smmu_domain);
>> +	xfree(smmu_domain);
>> }
>> 
>> 
>> @@ -1576,6 +1838,44 @@ static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
>> 	struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
>> 	typeof(&arm_lpae_s2_cfg.vtcr) vtcr = &arm_lpae_s2_cfg.vtcr;
>> 
>> +	vtcr->sh = ARM_SMMU_VTCR_SH_IS;
>> +	vtcr->irgn = ARM_SMMU_VTCR_RGN_WBWA;
>> +	vtcr->orgn = ARM_SMMU_VTCR_RGN_WBWA;
>> +
>> +	BUILD_BUG_ON(PAGE_SIZE != SZ_4K);
>> +	vtcr->tg = ARM_SMMU_VTCR_TG0_4K;
>> +
>> +	switch (smmu->oas) {
>> +	case 32:
>> +		vtcr->ps = ARM_SMMU_VTCR_PS_32_BIT;
>> +		break;
>> +	case 36:
>> +		vtcr->ps = ARM_SMMU_VTCR_PS_36_BIT;
>> +		break;
>> +	case 40:
>> +		vtcr->ps = ARM_SMMU_VTCR_PS_40_BIT;
>> +		break;
>> +	case 42:
>> +		vtcr->ps = ARM_SMMU_VTCR_PS_42_BIT;
>> +		break;
>> +	case 44:
>> +		vtcr->ps = ARM_SMMU_VTCR_PS_44_BIT;
>> +		break;
>> +	case 48:
>> +		vtcr->ps = ARM_SMMU_VTCR_PS_48_BIT;
>> +		break;
>> +	case 52:
>> +		vtcr->ps = ARM_SMMU_VTCR_PS_52_BIT;
>> +		break;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +
>> +	vtcr->tsz = 64 - p2m_ipa_bits;
>> +	vtcr->sl = 2 - P2M_ROOT_LEVEL;
>> +
>> +	arm_lpae_s2_cfg.vttbr  = page_to_maddr(smmu_domain->d->arch.p2m.root);
>> +
>> 	vmid = arm_smmu_bitmap_alloc(smmu->vmid_map, smmu->vmid_bits);
>> 	if (vmid < 0)
>> 		return vmid;
>> @@ -1589,6 +1889,11 @@ static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
>> 			  FIELD_PREP(STRTAB_STE_2_VTCR_S2SH0, vtcr->sh) |
>> 			  FIELD_PREP(STRTAB_STE_2_VTCR_S2TG, vtcr->tg) |
>> 			  FIELD_PREP(STRTAB_STE_2_VTCR_S2PS, vtcr->ps);
>> +
>> +	printk(XENLOG_DEBUG
>> +		   "SMMUv3: d%u: vmid 0x%x vtcr 0x%"PRIpaddr" p2maddr 0x%"PRIpaddr"\n",
>> +		   smmu_domain->d->domain_id, cfg->vmid, cfg->vtcr, cfg->vttbr);
>> +
>> 	return 0;
>> }
>> 
>> @@ -1650,6 +1955,7 @@ static void arm_smmu_install_ste_for_dev(struct arm_smmu_master *master)
>> 	}
>> }
>> 
>> +#ifdef CONFIG_PCI_ATS
>> static bool arm_smmu_ats_supported(struct arm_smmu_master *master)
>> {
>> 	struct device *dev = master->dev;
>> @@ -1748,6 +2054,23 @@ static void arm_smmu_disable_pasid(struct arm_smmu_master *master)
>> 
>> 	pci_disable_pasid(pdev);
>> }
>> +#else
>> +static inline bool arm_smmu_ats_supported(struct arm_smmu_master *master)
>> +{
>> +	return false;
>> +}
>> +
>> +static inline void arm_smmu_enable_ats(struct arm_smmu_master *master) { }
>> +
>> +static inline void arm_smmu_disable_ats(struct arm_smmu_master *master) { }
>> +
>> +static inline int arm_smmu_enable_pasid(struct arm_smmu_master *master)
>> +{
>> +	return 0;
>> +}
>> +
>> +static inline void arm_smmu_disable_pasid(struct arm_smmu_master *master) { }
>> +#endif /* CONFIG_PCI_ATS */
>> 
>> static void arm_smmu_detach_dev(struct arm_smmu_master *master)
>> {
>> @@ -1830,8 +2153,10 @@ static bool arm_smmu_sid_in_range(struct arm_smmu_device *smmu, u32 sid)
>> 
>> 	return sid < limit;
>> }
>> +/* Forward declaration */
>> +static struct arm_smmu_device *arm_smmu_get_by_dev(struct device *dev);
>> 
>> -static struct iommu_device *arm_smmu_probe_device(struct device *dev)
>> +static int arm_smmu_add_device(u8 devfn, struct device *dev)
>> {
>> 	int i, ret;
>> 	struct arm_smmu_device *smmu;
>> @@ -1839,14 +2164,15 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
>> 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
>> 
>> 	if (!fwspec)
>> -		return ERR_PTR(-ENODEV);
>> +		return -ENODEV;
>> 
>> -	if (WARN_ON_ONCE(dev_iommu_priv_get(dev)))
>> -		return ERR_PTR(-EBUSY);
>> +	smmu = arm_smmu_get_by_dev(fwspec->iommu_dev);
>> +	if (!smmu)
>> +		return -ENODEV;
>> 
>> -	master = kzalloc(sizeof(*master), GFP_KERNEL);
>> +	master = xzalloc(struct arm_smmu_master);
>> 	if (!master)
>> -		return ERR_PTR(-ENOMEM);
>> +		return -ENOMEM;
>> 
>> 	master->dev = dev;
>> 	master->smmu = smmu;
>> @@ -1881,17 +2207,36 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
>> 	 */
>> 	arm_smmu_enable_pasid(master);
>> 
>> -	return &smmu->iommu;
>> +	return 0;
>> 
>> err_free_master:
>> -	kfree(master);
>> +	xfree(master);
>> 	dev_iommu_priv_set(dev, NULL);
>> -	return ERR_PTR(ret);
>> +	return ret;
>> }
>> 
>> -static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args)
>> +static int arm_smmu_dt_xlate(struct device *dev,
>> +				const struct dt_phandle_args *args)
>> {
>> -	return iommu_fwspec_add_ids(dev, args->args, 1);
>> +	int ret;
>> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
>> +
>> +	ret = iommu_fwspec_add_ids(dev, args->args, 1);
>> +	if (ret)
>> +		return ret;
>> +
>> +	if (dt_device_is_protected(dev_to_dt(dev))) {
>> +		dev_err(dev, "Already added to SMMUv3\n");
>> +		return -EEXIST;
>> +	}
>> +
>> +	/* Let Xen know that the master device is protected by an IOMMU. */
>> +	dt_device_set_protected(dev_to_dt(dev));
>> +
>> +	dev_info(dev, "Added master device (SMMUv3 %s StreamIds %u)\n",
>> +			dev_name(fwspec->iommu_dev), fwspec->num_ids);
>> +
>> +	return 0;
>> }
>> 
>> /* Probing and initialisation functions */
>> @@ -1972,7 +2317,7 @@ static int arm_smmu_init_l1_strtab(struct arm_smmu_device *smmu)
>> 	size_t size = sizeof(*cfg->l1_desc) * cfg->num_l1_ents;
>> 	void *strtab = smmu->strtab_cfg.strtab;
>> 
>> -	cfg->l1_desc = devm_kzalloc(smmu->dev, size, GFP_KERNEL);
>> +	cfg->l1_desc = _xzalloc(size, sizeof(void *));
>> 	if (!cfg->l1_desc) {
>> 		dev_err(smmu->dev, "failed to allocate l1 stream table desc\n");
>> 		return -ENOMEM;
>> @@ -2118,6 +2463,7 @@ static int arm_smmu_update_gbpa(struct arm_smmu_device *smmu, u32 set, u32 clr)
>> 	return ret;
>> }
>> 
>> +#ifdef CONFIG_MSI
>> static void arm_smmu_free_msis(void *data)
>> {
>> 	struct device *dev = data;
>> @@ -2188,8 +2534,35 @@ static void arm_smmu_setup_msis(struct arm_smmu_device *smmu)
>> 	/* Add callback to free MSIs on teardown */
>> 	devm_add_action(dev, arm_smmu_free_msis, dev);
>> }
>> +#else
>> +static inline void arm_smmu_setup_msis(struct arm_smmu_device *smmu) { }
>> +#endif /* CONFIG_MSI */
>> 
>> -static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
>> +static void arm_smmu_free_irqs(struct arm_smmu_device *smmu)
>> +{
>> +	int irq;
>> +
>> +	irq = smmu->combined_irq;
>> +	if (irq)
>> +		release_irq(irq, smmu);
>> +	else {
>> +		irq = smmu->evtq.q.irq;
>> +		if (irq)
>> +			release_irq(irq, smmu);
>> +
>> +		irq = smmu->gerr_irq;
>> +		if (irq)
>> +			release_irq(irq, smmu);
>> +
>> +		if (smmu->features & ARM_SMMU_FEAT_PRI) {
>> +			irq = smmu->priq.q.irq;
>> +			if (irq)
>> +				release_irq(irq, smmu);
>> +		}
>> +	}
>> +}
>> +
>> +static int arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
>> {
>> 	int irq, ret;
>> 
>> @@ -2198,22 +2571,24 @@ static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
>> 	/* Request interrupt lines */
>> 	irq = smmu->evtq.q.irq;
>> 	if (irq) {
>> -		ret = devm_request_threaded_irq(smmu->dev, irq, NULL,
>> -						arm_smmu_evtq_thread,
>> -						IRQF_ONESHOT,
>> +		ret = request_irq(irq, 0, arm_smmu_evtq_irq_tasklet,
>> 						"arm-smmu-v3-evtq", smmu);
>> -		if (ret < 0)
>> +		if (ret < 0) {
>> 			dev_warn(smmu->dev, "failed to enable evtq irq\n");
>> +			return ret;
>> +		}
>> 	} else {
>> 		dev_warn(smmu->dev, "no evtq irq - events will not be reported!\n");
>> 	}
>> 
>> 	irq = smmu->gerr_irq;
>> 	if (irq) {
>> -		ret = devm_request_irq(smmu->dev, irq, arm_smmu_gerror_handler,
>> -				       0, "arm-smmu-v3-gerror", smmu);
>> -		if (ret < 0)
>> +		ret = request_irq(irq, 0, arm_smmu_gerror_handler,
>> +						"arm-smmu-v3-gerror", smmu);
>> +		if (ret < 0) {
>> 			dev_warn(smmu->dev, "failed to enable gerror irq\n");
>> +			goto err_free_evtq_irq;
>> +		}
>> 	} else {
>> 		dev_warn(smmu->dev, "no gerr irq - errors will not be reported!\n");
>> 	}
>> @@ -2221,18 +2596,30 @@ static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
>> 	if (smmu->features & ARM_SMMU_FEAT_PRI) {
>> 		irq = smmu->priq.q.irq;
>> 		if (irq) {
>> -			ret = devm_request_threaded_irq(smmu->dev, irq, NULL,
>> -							arm_smmu_priq_thread,
>> -							IRQF_ONESHOT,
>> -							"arm-smmu-v3-priq",
>> -							smmu);
>> -			if (ret < 0)
>> +			ret = request_irq(irq, 0, arm_smmu_priq_irq_tasklet,
>> +							"arm-smmu-v3-priq", smmu);
>> +			if (ret < 0) {
>> 				dev_warn(smmu->dev,
>> 					 "failed to enable priq irq\n");
>> +				goto err_free_gerr_irq;
>> +			}
>> 		} else {
>> 			dev_warn(smmu->dev, "no priq irq - PRI will be broken\n");
>> 		}
>> 	}
>> +
>> +	return 0;
>> +
>> +err_free_gerr_irq:
>> +	irq = smmu->gerr_irq;
>> +	if (irq)
>> +		release_irq(irq, smmu);
>> +err_free_evtq_irq:
>> +	irq = smmu->evtq.q.irq;
>> +	if (irq)
>> +		release_irq(irq, smmu);
>> +
>> +	return ret;
>> }
>> 
>> static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
>> @@ -2254,15 +2641,19 @@ static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
>> 		 * Cavium ThunderX2 implementation doesn't support unique irq
>> 		 * lines. Use a single irq line for all the SMMUv3 interrupts.
>> 		 */
>> -		ret = devm_request_threaded_irq(smmu->dev, irq,
>> -					arm_smmu_combined_irq_handler,
>> -					arm_smmu_combined_irq_thread,
>> -					IRQF_ONESHOT,
>> -					"arm-smmu-v3-combined-irq", smmu);
>> -		if (ret < 0)
>> +		ret = request_irq(irq, 0, arm_smmu_combined_irq_handler,
>> +						"arm-smmu-v3-combined-irq", smmu);
>> +		if (ret < 0) {
>> 			dev_warn(smmu->dev, "failed to enable combined irq\n");
>> -	} else
>> -		arm_smmu_setup_unique_irqs(smmu);
>> +			return ret;
>> +		}
>> +	} else {
>> +		ret = arm_smmu_setup_unique_irqs(smmu);
>> +		if (ret) {
>> +			dev_warn(smmu->dev, "failed to setup unique irqs\n");
>> +			return ret;
>> +		}
>> +	}
>> 
>> 	if (smmu->features & ARM_SMMU_FEAT_PRI)
>> 		irqen_flags |= IRQ_CTRL_PRIQ_IRQEN;
>> @@ -2270,10 +2661,16 @@ static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
>> 	/* Enable interrupt generation on the SMMU */
>> 	ret = arm_smmu_write_reg_sync(smmu, irqen_flags,
>> 				      ARM_SMMU_IRQ_CTRL, ARM_SMMU_IRQ_CTRLACK);
>> -	if (ret)
>> +	if (ret) {
>> 		dev_warn(smmu->dev, "failed to enable irqs\n");
>> +		goto err_free_irqs;
>> +	}
>> 
>> 	return 0;
>> +
>> +err_free_irqs:
>> +	arm_smmu_free_irqs(smmu);
>> +	return ret;
>> }
>> 
>> static int arm_smmu_device_disable(struct arm_smmu_device *smmu)
>> @@ -2287,7 +2684,7 @@ static int arm_smmu_device_disable(struct arm_smmu_device *smmu)
>> 	return ret;
>> }
>> 
>> -static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
>> +static int arm_smmu_device_reset(struct arm_smmu_device *smmu)
>> {
>> 	int ret;
>> 	u32 reg, enables;
>> @@ -2297,7 +2694,7 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
>> 	reg = readl_relaxed(smmu->base + ARM_SMMU_CR0);
>> 	if (reg & CR0_SMMUEN) {
>> 		dev_warn(smmu->dev, "SMMU currently enabled! Resetting...\n");
>> -		WARN_ON(is_kdump_kernel() && !disable_bypass);
>> +		WARN_ON(!disable_bypass);
>> 		arm_smmu_update_gbpa(smmu, GBPA_ABORT, 0);
>> 	}
>> 
>> @@ -2401,25 +2798,32 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
>> 		return ret;
>> 	}
>> 
>> -	if (is_kdump_kernel())
>> -		enables &= ~(CR0_EVTQEN | CR0_PRIQEN);
>> +	/* Initialize tasklets for threaded IRQs*/
>> +	tasklet_init(&smmu->evtq_irq_tasklet, arm_smmu_evtq_tasklet, smmu);
>> +	tasklet_init(&smmu->priq_irq_tasklet, arm_smmu_priq_tasklet, smmu);
>> +	tasklet_init(&smmu->combined_irq_tasklet, arm_smmu_combined_irq_tasklet,
>> +				 smmu);
>> 
>> 	/* Enable the SMMU interface, or ensure bypass */
>> -	if (!bypass || disable_bypass) {
>> +	if (disable_bypass) {
>> 		enables |= CR0_SMMUEN;
>> 	} else {
>> 		ret = arm_smmu_update_gbpa(smmu, 0, GBPA_ABORT);
>> 		if (ret)
>> -			return ret;
>> +			goto err_free_irqs;
>> 	}
>> 	ret = arm_smmu_write_reg_sync(smmu, enables, ARM_SMMU_CR0,
>> 				      ARM_SMMU_CR0ACK);
>> 	if (ret) {
>> 		dev_err(smmu->dev, "failed to enable SMMU interface\n");
>> -		return ret;
>> +		goto err_free_irqs;
>> 	}
>> 
>> 	return 0;
>> +
>> +err_free_irqs:
>> +	arm_smmu_free_irqs(smmu);
>> +	return ret;
>> }
>> 
>> static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>> @@ -2470,8 +2874,10 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>> 	if (reg & IDR0_SEV)
>> 		smmu->features |= ARM_SMMU_FEAT_SEV;
>> 
>> +#ifdef CONFIG_MSI
>> 	if (reg & IDR0_MSI)
>> 		smmu->features |= ARM_SMMU_FEAT_MSI;
>> +#endif
>> 
>> 	if (reg & IDR0_HYP)
>> 		smmu->features |= ARM_SMMU_FEAT_HYP;
>> @@ -2496,7 +2902,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>> 		smmu->features |= ARM_SMMU_FEAT_TRANS_S2;
>> 
>> 	if (!(reg & IDR0_S2P)) {
>> -		dev_err(smmu->dev, "no translation support!\n");
>> +		dev_err(smmu->dev, "no stage-2 translation support!\n");
>> 		return -ENXIO;
>> 	}
>> 
>> @@ -2593,8 +2999,12 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
>> 		smmu->oas = 48;
>> 	}
>> 
>> +	smmu->oas = min_t(unsigned long, PADDR_BITS, smmu->oas);
>> 	smmu->ias = max(smmu->ias, smmu->oas);
>> 
>> +	/* Xen: Set maximum Stage-2 input size supported by the SMMU. */
>> +	p2m_restrict_ipa_bits(smmu->ias);
>> +
>> 	dev_info(smmu->dev, "ias %lu-bit, oas %lu-bit (features 0x%08x)\n",
>> 		 smmu->ias, smmu->oas, smmu->features);
>> 	return 0;
>> @@ -2645,7 +3055,7 @@ static inline int arm_smmu_device_acpi_probe(struct platform_device *pdev,
>> static int arm_smmu_device_dt_probe(struct platform_device *pdev,
>> 				    struct arm_smmu_device *smmu)
>> {
>> -	struct device *dev = &pdev->dev;
>> +	struct device *dev = pdev;
>> 	u32 cells;
>> 	int ret = -EINVAL;
>> 
>> @@ -2658,7 +3068,7 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev,
>> 
>> 	parse_driver_options(smmu);
>> 
>> -	if (of_dma_is_coherent(dev->of_node))
>> +	if (dt_get_property(dev->of_node, "dma-coherent", NULL))
>> 		smmu->features |= ARM_SMMU_FEAT_COHERENCY;
>> 
>> 	return ret;
>> @@ -2672,66 +3082,76 @@ static unsigned long arm_smmu_resource_size(struct arm_smmu_device *smmu)
>> 		return SZ_128K;
>> }
>> 
>> -static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
>> -				      resource_size_t size)
>> +
>> +static void arm_smmu_free_structures(struct arm_smmu_device *smmu)
>> {
>> -	struct resource res = {
>> -		.flags = IORESOURCE_MEM,
>> -		.start = start,
>> -		.end = start + size - 1,
>> -	};
>> +	if (smmu->cmdq.q.base)
>> +		xfree(smmu->cmdq.q.base);
>> +
>> +	if (smmu->evtq.q.base)
>> +		xfree(smmu->evtq.q.base);
>> 
>> -	return devm_ioremap_resource(dev, &res);
>> +	if (smmu->priq.q.base)
>> +		xfree(smmu->priq.q.base);
>> +
>> +	if (smmu->strtab_cfg.strtab)
>> +		xfree(smmu->strtab_cfg.strtab);
>> +
>> +	if (smmu->strtab_cfg.l1_desc)
>> +		xfree(smmu->strtab_cfg.l1_desc);
> 
> From what I can tell we also need to free somewhere
> smmu->strtab_cfg->l1_desc->l2ptr allocated by arm_smmu_init_l2_strtab

"l1_desc->l2ptr" is a pointer to the Level 1 Stream Table Descriptor if 2-level Stream Table supported.

If the device is protected by IOMMU, SMMUv3 driver will allocate the  "l1_desc->l2ptr” when the device is added to the IOMMU via arm_smmu_add_device() function and device will be configured in bypass/abort mode.

Once we assign the device to the domain(arm_smmu_assign_dev() ) smmuv3 hw will be configured correctly to match the StreamID. If there is a failure in assigning the device, that case also XEN will not remove the device and master device still be in bypass/abort mode.

As in XEN, there is no function to remove the master device from the IOMMU, because of that I feel there is no need to free the "l1_desc->l2ptr” in case of failure also.

> 
>> }
>> 
>> static int arm_smmu_device_probe(struct platform_device *pdev)
>> {
>> 	int irq, ret;
>> -	struct resource *res;
>> -	resource_size_t ioaddr;
>> +	paddr_t ioaddr, iosize;
>> 	struct arm_smmu_device *smmu;
>> -	struct device *dev = &pdev->dev;
>> -	bool bypass;
>> 
>> -	smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
>> +	smmu = xzalloc(struct arm_smmu_device);
>> 	if (!smmu) {
>> -		dev_err(dev, "failed to allocate arm_smmu_device\n");
>> +		dev_err(pdev, "failed to allocate arm_smmu_device\n");
>> 		return -ENOMEM;
>> 	}
>> -	smmu->dev = dev;
>> +	smmu->dev = pdev;
>> 
>> -	if (dev->of_node) {
>> +	if (pdev->of_node) {
>> 		ret = arm_smmu_device_dt_probe(pdev, smmu);
>> +		if (ret)
>> +			goto out_free_smmu;
>> 	} else {
>> 		ret = arm_smmu_device_acpi_probe(pdev, smmu);
>> 		if (ret == -ENODEV)
> 
> I can see the if condition was already as is from previous patches but
> it would be better to do:
> 
> if (ret)
>    goto out_free_smmu;
> 
> It could be done on commit. Also, I am fine either way.

I am ok if it can be done on commit.

Regards,
Rahul
> 
> 
>> -			return ret;
>> +			goto out_free_smmu;
>> 	}
>> 
>> -	/* Set bypass mode according to firmware probing result */
>> -	bypass = !!ret;
>> -
>> 	/* Base address */
>> -	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> -	if (resource_size(res) < arm_smmu_resource_size(smmu)) {
>> -		dev_err(dev, "MMIO region too small (%pr)\n", res);
>> -		return -EINVAL;
>> +	ret = dt_device_get_address(dev_to_dt(pdev), 0, &ioaddr, &iosize);
>> +	if (ret)
>> +		goto out_free_smmu;
>> +
>> +	if (iosize < arm_smmu_resource_size(smmu)) {
>> +		dev_err(pdev, "MMIO region too small (%lx)\n", iosize);
>> +		ret = -EINVAL;
>> +		goto out_free_smmu;
>> 	}
>> -	ioaddr = res->start;
>> 
>> 	/*
>> 	 * Don't map the IMPLEMENTATION DEFINED regions, since they may contain
>> -	 * the PMCG registers which are reserved by the PMU driver.
>> +	 * the PMCG registers which are optional and currently not supported.
>> 	 */
>> -	smmu->base = arm_smmu_ioremap(dev, ioaddr, ARM_SMMU_REG_SZ);
>> -	if (IS_ERR(smmu->base))
>> -		return PTR_ERR(smmu->base);
>> +	smmu->base = ioremap_nocache(ioaddr, ARM_SMMU_REG_SZ);
>> +	if (IS_ERR(smmu->base)) {
>> +		ret = PTR_ERR(smmu->base);
>> +		goto out_free_smmu;
>> +	}
>> 
>> -	if (arm_smmu_resource_size(smmu) > SZ_64K) {
>> -		smmu->page1 = arm_smmu_ioremap(dev, ioaddr + SZ_64K,
>> +	if (iosize > SZ_64K) {
>> +		smmu->page1 = ioremap_nocache(ioaddr + SZ_64K,
>> 					       ARM_SMMU_REG_SZ);
>> -		if (IS_ERR(smmu->page1))
>> -			return PTR_ERR(smmu->page1);
>> +		if (IS_ERR(smmu->page1)) {
>> +			ret = PTR_ERR(smmu->page1);
>> +			goto out_free;
>> +		}
>> 	} else {
>> 		smmu->page1 = smmu->base;
>> 	}
>> @@ -2756,23 +3176,286 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
>> 	}
>> 	/* Probe the h/w */
>> 	ret = arm_smmu_device_hw_probe(smmu);
>> -	if (ret)
>> -		return ret;
>> +	if (ret) {
>> +		ret = -ENODEV;
>> +		goto out_free;
>> +	}
>> 
>> 	/* Initialise in-memory data structures */
>> 	ret = arm_smmu_init_structures(smmu);
>> 	if (ret)
>> -		return ret;
>> +		goto out_free;
>> 
>> 	/* Reset the device */
>> -	ret = arm_smmu_device_reset(smmu, bypass);
>> +	ret = arm_smmu_device_reset(smmu);
>> 	if (ret)
>> -		return ret;
>> +		goto out_free;
>> +
>> +	/*
>> +	 * Keep a list of all probed devices. This will be used to query
>> +	 * the smmu devices based on the fwnode.
>> +	 */
>> +	INIT_LIST_HEAD(&smmu->devices);
>> +
>> +	spin_lock(&arm_smmu_devices_lock);
>> +	list_add(&smmu->devices, &arm_smmu_devices);
>> +	spin_unlock(&arm_smmu_devices_lock);
>> 
>> 	return 0;
>> +
>> +
>> +out_free:
>> +	arm_smmu_free_structures(smmu);
>> +	if (smmu->page1)
>> +		iounmap(smmu->page1);
>> +	if (smmu->base)
>> +		iounmap(smmu->base);
>> +
>> +out_free_smmu:
>> +	xfree(smmu);
>> +
>> +	return ret;
>> }
>> 
>> -static const struct of_device_id arm_smmu_of_match[] = {
>> +static const struct dt_device_match arm_smmu_of_match[] = {
>> 	{ .compatible = "arm,smmu-v3", },
>> 	{ },
>> };
>> +
>> +/* Start of Xen specific code. */
>> +static int __must_check arm_smmu_iotlb_flush_all(struct domain *d)
>> +{
>> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
>> +	struct iommu_domain *io_domain;
>> +
>> +	spin_lock(&xen_domain->lock);
>> +
>> +	list_for_each_entry(io_domain, &xen_domain->contexts, list) {
>> +		/*
>> +		 * Only invalidate the context when SMMU is present.
>> +		 * This is because the context initialization is delayed
>> +		 * until a master has been added.
>> +		 */
>> +		if (unlikely(!ACCESS_ONCE(to_smmu_domain(io_domain)->smmu)))
>> +			continue;
>> +
>> +		arm_smmu_tlb_inv_context(to_smmu_domain(io_domain));
>> +	}
>> +
>> +	spin_unlock(&xen_domain->lock);
>> +
>> +	return 0;
>> +}
>> +
>> +static int __must_check arm_smmu_iotlb_flush(struct domain *d, dfn_t dfn,
>> +				unsigned long page_count, unsigned int flush_flags)
>> +{
>> +	return arm_smmu_iotlb_flush_all(d);
>> +}
>> +
>> +static struct arm_smmu_device *arm_smmu_get_by_dev(struct device *dev)
>> +{
>> +	struct arm_smmu_device *smmu = NULL;
>> +
>> +	spin_lock(&arm_smmu_devices_lock);
>> +
>> +	list_for_each_entry(smmu, &arm_smmu_devices, devices) {
>> +		if (smmu->dev  == dev) {
>> +			spin_unlock(&arm_smmu_devices_lock);
>> +			return smmu;
>> +		}
>> +	}
>> +
>> +	spin_unlock(&arm_smmu_devices_lock);
>> +
>> +	return NULL;
>> +}
>> +
>> +static struct iommu_domain *arm_smmu_get_domain(struct domain *d,
>> +				struct device *dev)
>> +{
>> +	struct iommu_domain *io_domain;
>> +	struct arm_smmu_domain *smmu_domain;
>> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
>> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
>> +	struct arm_smmu_device *smmu = arm_smmu_get_by_dev(fwspec->iommu_dev);
>> +
>> +	if (!smmu)
>> +		return NULL;
>> +
>> +	/*
>> +	 * Loop through the &xen_domain->contexts to locate a context
>> +	 * assigned to this SMMU
>> +	 */
>> +	list_for_each_entry(io_domain, &xen_domain->contexts, list) {
>> +		smmu_domain = to_smmu_domain(io_domain);
>> +		if (smmu_domain->smmu == smmu)
>> +			return io_domain;
>> +	}
>> +	return NULL;
>> +}
>> +
>> +static void arm_smmu_destroy_iommu_domain(struct iommu_domain *io_domain)
>> +{
>> +	list_del(&io_domain->list);
>> +	arm_smmu_domain_free(io_domain);
>> +}
>> +
>> +static int arm_smmu_assign_dev(struct domain *d, u8 devfn,
>> +		struct device *dev, u32 flag)
>> +{
>> +	int ret = 0;
>> +	struct iommu_domain *io_domain;
>> +	struct arm_smmu_domain *smmu_domain;
>> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
>> +
>> +	spin_lock(&xen_domain->lock);
>> +
>> +	/*
>> +	 * Check to see if an iommu_domain already exists for this xen domain
>> +	 * under the same SMMU
>> +	 */
>> +	io_domain = arm_smmu_get_domain(d, dev);
>> +	if (!io_domain) {
>> +		io_domain = arm_smmu_domain_alloc();
>> +		if (!io_domain) {
>> +			ret = -ENOMEM;
>> +			goto out;
>> +		}
>> +		smmu_domain = to_smmu_domain(io_domain);
>> +		smmu_domain->d = d;
>> +
>> +		/* Chain the new context to the domain */
>> +		list_add(&io_domain->list, &xen_domain->contexts);
>> +	}
>> +
>> +	ret = arm_smmu_attach_dev(io_domain, dev);
>> +	if (ret) {
>> +		if (io_domain->ref.counter == 0)
>> +			arm_smmu_destroy_iommu_domain(io_domain);
>> +	} else {
>> +		atomic_inc(&io_domain->ref);
>> +	}
>> +
>> +out:
>> +	spin_unlock(&xen_domain->lock);
>> +	return ret;
>> +}
>> +
>> +static int arm_smmu_deassign_dev(struct domain *d, struct device *dev)
>> +{
>> +	struct iommu_domain *io_domain = arm_smmu_get_domain(d, dev);
>> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
>> +	struct arm_smmu_domain *smmu_domain = to_smmu_domain(io_domain);
>> +	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
>> +
>> +	if (!smmu_domain || smmu_domain->d != d) {
>> +		dev_err(dev, " not attached to domain %d\n", d->domain_id);
>> +		return -ESRCH;
>> +	}
>> +
>> +	spin_lock(&xen_domain->lock);
>> +
>> +	arm_smmu_detach_dev(master);
>> +	atomic_dec(&io_domain->ref);
>> +
>> +	if (io_domain->ref.counter == 0)
>> +		arm_smmu_destroy_iommu_domain(io_domain);
>> +
>> +	spin_unlock(&xen_domain->lock);
>> +
>> +	return 0;
>> +}
>> +
>> +static int arm_smmu_reassign_dev(struct domain *s, struct domain *t,
>> +				u8 devfn,  struct device *dev)
>> +{
>> +	int ret = 0;
>> +
>> +	/* Don't allow remapping on other domain than hwdom */
>> +	if (t && t != hardware_domain)
>> +		return -EPERM;
>> +
>> +	if (t == s)
>> +		return 0;
>> +
>> +	ret = arm_smmu_deassign_dev(s, dev);
>> +	if (ret)
>> +		return ret;
>> +
>> +	if (t) {
>> +		/* No flags are defined for ARM. */
>> +		ret = arm_smmu_assign_dev(t, devfn, dev, 0);
>> +		if (ret)
>> +			return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int arm_smmu_iommu_xen_domain_init(struct domain *d)
>> +{
>> +	struct arm_smmu_xen_domain *xen_domain;
>> +
>> +	xen_domain = xzalloc(struct arm_smmu_xen_domain);
>> +	if (!xen_domain)
>> +		return -ENOMEM;
>> +
>> +	spin_lock_init(&xen_domain->lock);
>> +	INIT_LIST_HEAD(&xen_domain->contexts);
>> +
>> +	dom_iommu(d)->arch.priv = xen_domain;
>> +	return 0;
>> +
>> +}
>> +
>> +static void __hwdom_init arm_smmu_iommu_hwdom_init(struct domain *d)
>> +{
>> +}
>> +
>> +static void arm_smmu_iommu_xen_domain_teardown(struct domain *d)
>> +{
>> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
>> +
>> +	ASSERT(list_empty(&xen_domain->contexts));
>> +	xfree(xen_domain);
>> +}
>> +
>> +static const struct iommu_ops arm_smmu_iommu_ops = {
>> +	.init		= arm_smmu_iommu_xen_domain_init,
>> +	.hwdom_init		= arm_smmu_iommu_hwdom_init,
>> +	.teardown		= arm_smmu_iommu_xen_domain_teardown,
>> +	.iotlb_flush		= arm_smmu_iotlb_flush,
>> +	.iotlb_flush_all	= arm_smmu_iotlb_flush_all,
>> +	.assign_device		= arm_smmu_assign_dev,
>> +	.reassign_device	= arm_smmu_reassign_dev,
>> +	.map_page		= arm_iommu_map_page,
>> +	.unmap_page		= arm_iommu_unmap_page,
>> +	.dt_xlate		= arm_smmu_dt_xlate,
>> +	.add_device		= arm_smmu_add_device,
>> +};
>> +
>> +static __init int arm_smmu_dt_init(struct dt_device_node *dev,
>> +				const void *data)
>> +{
>> +	int rc;
>> +
>> +	/*
>> +	 * Even if the device can't be initialized, we don't want to
>> +	 * give the SMMU device to dom0.
>> +	 */
>> +	dt_device_set_used_by(dev, DOMID_XEN);
>> +
>> +	rc = arm_smmu_device_probe(dt_to_dev(dev));
>> +	if (rc)
>> +		return rc;
>> +
>> +	iommu_set_ops(&arm_smmu_iommu_ops);
>> +
>> +	return 0;
>> +}
>> +
>> +DT_DEVICE_START(smmuv3, "ARM SMMU V3", DEVICE_IOMMU)
>> +.dt_match = arm_smmu_of_match,
>> +.init = arm_smmu_dt_init,
>> +DT_DEVICE_END
>> -- 
>> 2.17.1


^ permalink raw reply	[flat|nested] 24+ messages in thread

* Re: [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver
  2021-01-20 21:33   ` Oleksandr
@ 2021-01-21 17:18     ` Rahul Singh
  2021-01-21 18:31       ` Julien Grall
  0 siblings, 1 reply; 24+ messages in thread
From: Rahul Singh @ 2021-01-21 17:18 UTC (permalink / raw)
  To: Oleksandr
  Cc: xen-devel, Bertrand Marquis, Andrew Cooper, George Dunlap,
	Ian Jackson, Jan Beulich, Julien Grall, Stefano Stabellini,
	Wei Liu, Paul Durrant, Volodymyr Babchuk

Hello Oleksandr,

> On 20 Jan 2021, at 9:33 pm, Oleksandr <olekstysh@gmail.com> wrote:
> 
> 
> On 20.01.21 16:52, Rahul Singh wrote:
> 
> Hi Rahul
> 
>> Add support for ARM architected SMMUv3 implementation. It is based on
>> the Linux SMMUv3 driver.
>> 
>> Driver is currently supported as Tech Preview.
>> 
>> Major differences with regard to Linux driver are as follows:
>> 2. Only Stage-2 translation is supported as compared to the Linux driver
>>    that supports both Stage-1 and Stage-2 translations.
>> 3. Use P2M  page table instead of creating one as SMMUv3 has the
>>    capability to share the page tables with the CPU.
>> 4. Tasklets are used in place of threaded IRQ's in Linux for event queue
>>    and priority queue IRQ handling.
>> 5. Latest version of the Linux SMMUv3 code implements the commands queue
>>    access functions based on atomic operations implemented in Linux.
>>    Atomic functions used by the commands queue access functions are not
>>    implemented in XEN therefore we decided to port the earlier version
>>    of the code. Atomic operations are introduced to fix the bottleneck
>>    of the SMMU command queue insertion operation. A new algorithm for
>>    inserting commands into the queue is introduced, which is lock-free
>>    on the fast-path.
>>    Consequence of reverting the patch is that the command queue
>>    insertion will be slow for large systems as spinlock will be used to
>>    serializes accesses from all CPUs to the single queue supported by
>>    the hardware. Once the proper atomic operations will be available in
>>    XEN the driver can be updated.
>> 6. Spin lock is used in place of mutex when attaching a device to the
>>    SMMU, as there is no blocking locks implementation available in XEN.
>>    This might introduce latency in XEN. Need to investigate before
>>    driver is out for tech preview.
>> 7. PCI ATS functionality is not supported, as there is no support
>>    available in XEN to test the functionality. Code is not tested and
>>    compiled. Code is guarded by the flag CONFIG_PCI_ATS.
>> 8. MSI interrupts are not supported as there is no support available in
>>    XEN to request MSI interrupts. Code is not tested and compiled. Code
>>    is guarded by the flag CONFIG_MSI.
>> 
>> Signed-off-by: Rahul Singh <rahul.singh@arm.com>
>> ---
>> Changes since v2:
>> - added return statement for readx_poll_timeout function.
>> - remove iommu_get_dma_cookie and iommu_put_dma_cookie.
>> - remove struct arm_smmu_xen_device as not required.
>> - move dt_property_match_string to device_tree.c file.
>> - replace arm_smmu_*_thread to arm_smmu_*_tasklet to avoid confusion.
>> - use ARM_SMMU_REG_SZ as size when map memory to XEN.
>> - remove bypass keyword to make sure when device-tree probe is failed we
>>   are reporting error and not continuing to configure SMMU in bypass
>>   mode.
>> - fixed minor comments.
>> Changes since v3:
>> - Fixed typo for CONFIG_MSI
>> - Added back the mutex code
>> - Rebase the patch on top of newly added WARN_ON().
>> - Remove the direct read of register VTCR_EL2.
>> - Fixed minor comments.
>> Changes since v4:
>> - Replace the ffsll() with ffs64() function.
>> - Add code to free resources when probe failed.
> 
> Thank you for addressing, patch looks ok to me, just one small remark below:
> 
> 
>> +
>> +static void __hwdom_init arm_smmu_iommu_hwdom_init(struct domain *d)
>> +{
>> +}
> 
> We discussed in V4 about adding some code here which all IOMMUs on Arm already have, copy it below for the convenience:
> 
> 
>      /* Set to false options not supported on ARM. */
>      if ( iommu_hwdom_inclusive )
>          printk(XENLOG_WARNING
>          "map-inclusive dom0-iommu option is not supported on ARM\n");
>      iommu_hwdom_inclusive = false;
>      if ( iommu_hwdom_reserved == 1 )
>          printk(XENLOG_WARNING
>          "map-reserved dom0-iommu option is not supported on ARM\n");
>      iommu_hwdom_reserved = 0;
> 
>      arch_iommu_hwdom_init(d);
> 
> 
> Also we discussed about possibility to fold the part of code (which disables unsupported options) in arch_iommu_hwdom_init() to avoid duplication as a follow-up.
> At least, I expected to see arch_iommu_hwdom_init() to be called by arm_smmu_iommu_hwdom_init() it current patch... Please note, this is *not* a request for change immediately,
> I think, driver is functional even without this code (hopefully arch_iommu_hwdom_init is empty now, etc).  But, if you happen to do V6 or probably it could be done on commit ...
> 

Yes I will send the patch to move the code to arch_iommu_hwdom_init() to avoid duplication once SMMUv3 driver will be merged.
I thought anyway I have to remove the code from SMMUv1 and IPMMU I will take care of all the IOMMU driver at the same time because of that I didn’t modify the SMMUv3 driver. Yes if there is a need for v6 I will add the arch_iommu_hwdom_init(d) in arm_smmu_iommu_hwdom_init().

Regards,
Rahul

> 
>> +
>> +static void arm_smmu_iommu_xen_domain_teardown(struct domain *d)
>> +{
>> +	struct arm_smmu_xen_domain *xen_domain = dom_iommu(d)->arch.priv;
>> +
>> +	ASSERT(list_empty(&xen_domain->contexts));
>> +	xfree(xen_domain);
>> +}
>> +
>> +static const struct iommu_ops arm_smmu_iommu_ops = {
>> +	.init		= arm_smmu_iommu_xen_domain_init,
>> +	.hwdom_init		= arm_smmu_iommu_hwdom_init,
>> +	.teardown		= arm_smmu_iommu_xen_domain_teardown,
>> +	.iotlb_flush		= arm_smmu_iotlb_flush,
>> +	.iotlb_flush_all	= arm_smmu_iotlb_flush_all,
>> +	.assign_device		= arm_smmu_assign_dev,
>> +	.reassign_device	= arm_smmu_reassign_dev,
>> +	.map_page		= arm_iommu_map_page,
>> +	.unmap_page		= arm_iommu_unmap_page,
>> +	.dt_xlate		= arm_smmu_dt_xlate,
>> +	.add_device		= arm_smmu_add_device,
>> +};
>> +
>> +static __init int arm_smmu_dt_init(struct dt_device_node *dev,
>> +				const void *data)
>> +{
>> +	int rc;
>> +
>> +	/*
>> +	 * Even if the device can't be initialized, we don't want to
>> +	 * give the SMMU device to dom0.
>> +	 */
>> +	dt_device_set_used_by(dev, DOMID_XEN);
>> +
>> +	rc = arm_smmu_device_probe(dt_to_dev(dev));
>> +	if (rc)
>> +		return rc;
>> +
>> +	iommu_set_ops(&arm_smmu_iommu_ops);
>> +
>> +	return 0;
>> +}
>> +
>> +DT_DEVICE_START(smmuv3, "ARM SMMU V3", DEVICE_IOMMU)
>> +.dt_match = arm_smmu_of_match,
>> +.init = arm_smmu_dt_init,
>> +DT_DEVICE_END
> 
> -- 
> Regards,
> 
> Oleksandr Tyshchenko


^ permalink raw reply	[flat|nested] 24+ messages in thread

* Re: [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver
  2021-01-21 17:18     ` Rahul Singh
@ 2021-01-21 18:31       ` Julien Grall
  2021-01-21 18:50         ` Rahul Singh
  0 siblings, 1 reply; 24+ messages in thread
From: Julien Grall @ 2021-01-21 18:31 UTC (permalink / raw)
  To: Rahul Singh, Oleksandr
  Cc: xen-devel, Bertrand Marquis, Andrew Cooper, George Dunlap,
	Ian Jackson, Jan Beulich, Stefano Stabellini, Wei Liu,
	Paul Durrant, Volodymyr Babchuk

On 21/01/2021 17:18, Rahul Singh wrote:
> Hello Oleksandr,

Hi,

>> On 20 Jan 2021, at 9:33 pm, Oleksandr <olekstysh@gmail.com> wrote:
>>
>>
>> On 20.01.21 16:52, Rahul Singh wrote:
>>
>> Hi Rahul
>>
>>> Add support for ARM architected SMMUv3 implementation. It is based on
>>> the Linux SMMUv3 driver.
>>>
>>> Driver is currently supported as Tech Preview.
>>>
>>> Major differences with regard to Linux driver are as follows:
>>> 2. Only Stage-2 translation is supported as compared to the Linux driver
>>>     that supports both Stage-1 and Stage-2 translations.
>>> 3. Use P2M  page table instead of creating one as SMMUv3 has the
>>>     capability to share the page tables with the CPU.
>>> 4. Tasklets are used in place of threaded IRQ's in Linux for event queue
>>>     and priority queue IRQ handling.
>>> 5. Latest version of the Linux SMMUv3 code implements the commands queue
>>>     access functions based on atomic operations implemented in Linux.
>>>     Atomic functions used by the commands queue access functions are not
>>>     implemented in XEN therefore we decided to port the earlier version
>>>     of the code. Atomic operations are introduced to fix the bottleneck
>>>     of the SMMU command queue insertion operation. A new algorithm for
>>>     inserting commands into the queue is introduced, which is lock-free
>>>     on the fast-path.
>>>     Consequence of reverting the patch is that the command queue
>>>     insertion will be slow for large systems as spinlock will be used to
>>>     serializes accesses from all CPUs to the single queue supported by
>>>     the hardware. Once the proper atomic operations will be available in
>>>     XEN the driver can be updated.
>>> 6. Spin lock is used in place of mutex when attaching a device to the
>>>     SMMU, as there is no blocking locks implementation available in XEN.
>>>     This might introduce latency in XEN. Need to investigate before
>>>     driver is out for tech preview.
>>> 7. PCI ATS functionality is not supported, as there is no support
>>>     available in XEN to test the functionality. Code is not tested and
>>>     compiled. Code is guarded by the flag CONFIG_PCI_ATS.
>>> 8. MSI interrupts are not supported as there is no support available in
>>>     XEN to request MSI interrupts. Code is not tested and compiled. Code
>>>     is guarded by the flag CONFIG_MSI.
>>>
>>> Signed-off-by: Rahul Singh <rahul.singh@arm.com>
>>> ---
>>> Changes since v2:
>>> - added return statement for readx_poll_timeout function.
>>> - remove iommu_get_dma_cookie and iommu_put_dma_cookie.
>>> - remove struct arm_smmu_xen_device as not required.
>>> - move dt_property_match_string to device_tree.c file.
>>> - replace arm_smmu_*_thread to arm_smmu_*_tasklet to avoid confusion.
>>> - use ARM_SMMU_REG_SZ as size when map memory to XEN.
>>> - remove bypass keyword to make sure when device-tree probe is failed we
>>>    are reporting error and not continuing to configure SMMU in bypass
>>>    mode.
>>> - fixed minor comments.
>>> Changes since v3:
>>> - Fixed typo for CONFIG_MSI
>>> - Added back the mutex code
>>> - Rebase the patch on top of newly added WARN_ON().
>>> - Remove the direct read of register VTCR_EL2.
>>> - Fixed minor comments.
>>> Changes since v4:
>>> - Replace the ffsll() with ffs64() function.
>>> - Add code to free resources when probe failed.
>>
>> Thank you for addressing, patch looks ok to me, just one small remark below:
>>
>>
>>> +
>>> +static void __hwdom_init arm_smmu_iommu_hwdom_init(struct domain *d)
>>> +{
>>> +}
>>
>> We discussed in V4 about adding some code here which all IOMMUs on Arm already have, copy it below for the convenience:
>>
>>
>>       /* Set to false options not supported on ARM. */
>>       if ( iommu_hwdom_inclusive )
>>           printk(XENLOG_WARNING
>>           "map-inclusive dom0-iommu option is not supported on ARM\n");
>>       iommu_hwdom_inclusive = false;
>>       if ( iommu_hwdom_reserved == 1 )
>>           printk(XENLOG_WARNING
>>           "map-reserved dom0-iommu option is not supported on ARM\n");
>>       iommu_hwdom_reserved = 0;
>>
>>       arch_iommu_hwdom_init(d);
>>
>>
>> Also we discussed about possibility to fold the part of code (which disables unsupported options) in arch_iommu_hwdom_init() to avoid duplication as a follow-up.
>> At least, I expected to see arch_iommu_hwdom_init() to be called by arm_smmu_iommu_hwdom_init() it current patch... Please note, this is *not* a request for change immediately,
>> I think, driver is functional even without this code (hopefully arch_iommu_hwdom_init is empty now, etc).  But, if you happen to do V6 or probably it could be done on commit ...
>>
> 
> Yes I will send the patch to move the code to arch_iommu_hwdom_init() to avoid duplication once SMMUv3 driver will be merged.
> I thought anyway I have to remove the code from SMMUv1 and IPMMU I will take care of all the IOMMU driver at the same time because of that I didn’t modify the SMMUv3 driver.

There are two part in the problem here:
   1) Code duplication
   2) The SMMUv3 not checking the command line and calling 
arch_iommu_hwdom_init(d)

I agree that 1) can be deferred because it is a clean-up. However, I 
consider 2) a (latent) bug because it means that we risk unintentionally 
breaking the SMMUv3 driver is we need to add code in 
arch_iommu_hwdom_init() as part of a future bug fix for 4.15.

Therefore...

> Yes if there is a need for v6 I will add the arch_iommu_hwdom_init(d) in arm_smmu_iommu_hwdom_init().

... I think calling arch_iommu_hwdom_init() should be the strict 
minimum. So please address it. Although, no need to resend the full 
series, you can only resend patch #10.

Cheers,

-- 
Julien Grall


^ permalink raw reply	[flat|nested] 24+ messages in thread

* Re: [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver
  2021-01-21 17:10     ` Rahul Singh
@ 2021-01-21 18:43       ` Julien Grall
  2021-01-21 20:28         ` Rahul Singh
  0 siblings, 1 reply; 24+ messages in thread
From: Julien Grall @ 2021-01-21 18:43 UTC (permalink / raw)
  To: Rahul Singh, Stefano Stabellini
  Cc: xen-devel, Bertrand Marquis, Andrew Cooper, George Dunlap,
	Ian Jackson, Jan Beulich, Wei Liu, Paul Durrant,
	Volodymyr Babchuk

Hi Rahul,

Please try to trim the e-mail when quoting, otherwise it is quite 
difficult to find the only couple of answer you wrote.

On 21/01/2021 17:10, Rahul Singh wrote:
>> On 20 Jan 2021, at 8:31 pm, Stefano Stabellini <sstabellini@kernel.org> wrote:
>>> -static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
>>> -				      resource_size_t size)
>>> +
>>> +static void arm_smmu_free_structures(struct arm_smmu_device *smmu)
>>> {
>>> -	struct resource res = {
>>> -		.flags = IORESOURCE_MEM,
>>> -		.start = start,
>>> -		.end = start + size - 1,
>>> -	};
>>> +	if (smmu->cmdq.q.base)
>>> +		xfree(smmu->cmdq.q.base);
>>> +
>>> +	if (smmu->evtq.q.base)
>>> +		xfree(smmu->evtq.q.base);
>>>
>>> -	return devm_ioremap_resource(dev, &res);
>>> +	if (smmu->priq.q.base)
>>> +		xfree(smmu->priq.q.base);
>>> +
>>> +	if (smmu->strtab_cfg.strtab)
>>> +		xfree(smmu->strtab_cfg.strtab);
>>> +
>>> +	if (smmu->strtab_cfg.l1_desc)
>>> +		xfree(smmu->strtab_cfg.l1_desc);
>>
>>  From what I can tell we also need to free somewhere
>> smmu->strtab_cfg->l1_desc->l2ptr allocated by arm_smmu_init_l2_strtab
> 
> "l1_desc->l2ptr" is a pointer to the Level 1 Stream Table Descriptor if 2-level Stream Table supported.
> 
> If the device is protected by IOMMU, SMMUv3 driver will allocate the  "l1_desc->l2ptr” when the device is added to the IOMMU via arm_smmu_add_device() function and device will be configured in bypass/abort mode.
> 
> Once we assign the device to the domain(arm_smmu_assign_dev() ) smmuv3 hw will be configured correctly to match the StreamID. If there is a failure in assigning the device, that case also XEN will not remove the device and master device still be in bypass/abort mode.

I am a bit confused with this answer. Wouldn't this mean that we are 
"leaking" memory if we fail to assign the device?

> 
> As in XEN, there is no function to remove the master device from the IOMMU, because of that I feel there is no need to free the "l1_desc->l2ptr” in case of failure also.

Hmmm... Xen is able to remove device from the IOMMU. The reason this is 
not implemented yet on Arm is because you can't hot-unplug "platform" 
device.

I expect the removal function to be useful for PCI.

Cheers,

-- 
Julien Grall


^ permalink raw reply	[flat|nested] 24+ messages in thread

* Re: [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver
  2021-01-21 18:31       ` Julien Grall
@ 2021-01-21 18:50         ` Rahul Singh
  2021-01-21 20:19           ` Julien Grall
  0 siblings, 1 reply; 24+ messages in thread
From: Rahul Singh @ 2021-01-21 18:50 UTC (permalink / raw)
  To: Julien Grall
  Cc: Oleksandr, xen-devel, Bertrand Marquis, Andrew Cooper,
	George Dunlap, Ian Jackson, Jan Beulich, Stefano Stabellini,
	Wei Liu, Paul Durrant, Volodymyr Babchuk

Hello Julien,

> On 21 Jan 2021, at 6:31 pm, Julien Grall <julien@xen.org> wrote:
> 
> On 21/01/2021 17:18, Rahul Singh wrote:
>> Hello Oleksandr,
> 
> Hi,
> 
>>> On 20 Jan 2021, at 9:33 pm, Oleksandr <olekstysh@gmail.com> wrote:
>>> 
>>> 
>>> On 20.01.21 16:52, Rahul Singh wrote:
>>> 
>>> Hi Rahul
>>> 
>>>> Add support for ARM architected SMMUv3 implementation. It is based on
>>>> the Linux SMMUv3 driver.
>>>> 
>>>> Driver is currently supported as Tech Preview.
>>>> 
>>>> Major differences with regard to Linux driver are as follows:
>>>> 2. Only Stage-2 translation is supported as compared to the Linux driver
>>>>    that supports both Stage-1 and Stage-2 translations.
>>>> 3. Use P2M  page table instead of creating one as SMMUv3 has the
>>>>    capability to share the page tables with the CPU.
>>>> 4. Tasklets are used in place of threaded IRQ's in Linux for event queue
>>>>    and priority queue IRQ handling.
>>>> 5. Latest version of the Linux SMMUv3 code implements the commands queue
>>>>    access functions based on atomic operations implemented in Linux.
>>>>    Atomic functions used by the commands queue access functions are not
>>>>    implemented in XEN therefore we decided to port the earlier version
>>>>    of the code. Atomic operations are introduced to fix the bottleneck
>>>>    of the SMMU command queue insertion operation. A new algorithm for
>>>>    inserting commands into the queue is introduced, which is lock-free
>>>>    on the fast-path.
>>>>    Consequence of reverting the patch is that the command queue
>>>>    insertion will be slow for large systems as spinlock will be used to
>>>>    serializes accesses from all CPUs to the single queue supported by
>>>>    the hardware. Once the proper atomic operations will be available in
>>>>    XEN the driver can be updated.
>>>> 6. Spin lock is used in place of mutex when attaching a device to the
>>>>    SMMU, as there is no blocking locks implementation available in XEN.
>>>>    This might introduce latency in XEN. Need to investigate before
>>>>    driver is out for tech preview.
>>>> 7. PCI ATS functionality is not supported, as there is no support
>>>>    available in XEN to test the functionality. Code is not tested and
>>>>    compiled. Code is guarded by the flag CONFIG_PCI_ATS.
>>>> 8. MSI interrupts are not supported as there is no support available in
>>>>    XEN to request MSI interrupts. Code is not tested and compiled. Code
>>>>    is guarded by the flag CONFIG_MSI.
>>>> 
>>>> Signed-off-by: Rahul Singh <rahul.singh@arm.com>
>>>> ---
>>>> Changes since v2:
>>>> - added return statement for readx_poll_timeout function.
>>>> - remove iommu_get_dma_cookie and iommu_put_dma_cookie.
>>>> - remove struct arm_smmu_xen_device as not required.
>>>> - move dt_property_match_string to device_tree.c file.
>>>> - replace arm_smmu_*_thread to arm_smmu_*_tasklet to avoid confusion.
>>>> - use ARM_SMMU_REG_SZ as size when map memory to XEN.
>>>> - remove bypass keyword to make sure when device-tree probe is failed we
>>>>   are reporting error and not continuing to configure SMMU in bypass
>>>>   mode.
>>>> - fixed minor comments.
>>>> Changes since v3:
>>>> - Fixed typo for CONFIG_MSI
>>>> - Added back the mutex code
>>>> - Rebase the patch on top of newly added WARN_ON().
>>>> - Remove the direct read of register VTCR_EL2.
>>>> - Fixed minor comments.
>>>> Changes since v4:
>>>> - Replace the ffsll() with ffs64() function.
>>>> - Add code to free resources when probe failed.
>>> 
>>> Thank you for addressing, patch looks ok to me, just one small remark below:
>>> 
>>> 
>>>> +
>>>> +static void __hwdom_init arm_smmu_iommu_hwdom_init(struct domain *d)
>>>> +{
>>>> +}
>>> 
>>> We discussed in V4 about adding some code here which all IOMMUs on Arm already have, copy it below for the convenience:
>>> 
>>> 
>>>      /* Set to false options not supported on ARM. */
>>>      if ( iommu_hwdom_inclusive )
>>>          printk(XENLOG_WARNING
>>>          "map-inclusive dom0-iommu option is not supported on ARM\n");
>>>      iommu_hwdom_inclusive = false;
>>>      if ( iommu_hwdom_reserved == 1 )
>>>          printk(XENLOG_WARNING
>>>          "map-reserved dom0-iommu option is not supported on ARM\n");
>>>      iommu_hwdom_reserved = 0;
>>> 
>>>      arch_iommu_hwdom_init(d);
>>> 
>>> 
>>> Also we discussed about possibility to fold the part of code (which disables unsupported options) in arch_iommu_hwdom_init() to avoid duplication as a follow-up.
>>> At least, I expected to see arch_iommu_hwdom_init() to be called by arm_smmu_iommu_hwdom_init() it current patch... Please note, this is *not* a request for change immediately,
>>> I think, driver is functional even without this code (hopefully arch_iommu_hwdom_init is empty now, etc).  But, if you happen to do V6 or probably it could be done on commit ...
>>> 
>> Yes I will send the patch to move the code to arch_iommu_hwdom_init() to avoid duplication once SMMUv3 driver will be merged.
>> I thought anyway I have to remove the code from SMMUv1 and IPMMU I will take care of all the IOMMU driver at the same time because of that I didn’t modify the SMMUv3 driver.
> 
> There are two part in the problem here:
>  1) Code duplication
>  2) The SMMUv3 not checking the command line and calling arch_iommu_hwdom_init(d)
> 
> I agree that 1) can be deferred because it is a clean-up. However, I consider 2) a (latent) bug because it means that we risk unintentionally breaking the SMMUv3 driver is we need to add code in arch_iommu_hwdom_init() as part of a future bug fix for 4.15.
> 
> Therefore...
> 
>> Yes if there is a need for v6 I will add the arch_iommu_hwdom_init(d) in arm_smmu_iommu_hwdom_init().
> 
> ... I think calling arch_iommu_hwdom_init() should be the strict minimum. So please address it. Although, no need to resend the full series, you can only resend patch #10.

Ok. I agree with you I will send the next version to fix the same.  Please suggest do you want me to check command line also in SMMUv3 now and later remove the code once I will send the patch to move duplicate code. 

---
/* Set to false options not supported on ARM. */                            
    if ( iommu_hwdom_inclusive )                                                
        printk(XENLOG_WARNING                                                   
        "map-inclusive dom0-iommu option is not supported on ARM\n");           
    iommu_hwdom_inclusive = false;                                              
    if ( iommu_hwdom_reserved == 1 )                                            
        printk(XENLOG_WARNING                                                   
        "map-reserved dom0-iommu option is not supported on ARM\n");            
    iommu_hwdom_reserved = 0;                                                   
                                                                                
    arch_iommu_hwdom_init(d);

--


Regards,
Rahul

> 
> Cheers,
> 
> -- 
> Julien Grall


^ permalink raw reply	[flat|nested] 24+ messages in thread

* Re: [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver
  2021-01-21 18:50         ` Rahul Singh
@ 2021-01-21 20:19           ` Julien Grall
  0 siblings, 0 replies; 24+ messages in thread
From: Julien Grall @ 2021-01-21 20:19 UTC (permalink / raw)
  To: Rahul Singh
  Cc: Oleksandr, xen-devel, Bertrand Marquis, Andrew Cooper,
	George Dunlap, Ian Jackson, Jan Beulich, Stefano Stabellini,
	Wei Liu, Paul Durrant, Volodymyr Babchuk



On 21/01/2021 18:50, Rahul Singh wrote:
> Hello Julien,
> 
>> On 21 Jan 2021, at 6:31 pm, Julien Grall <julien@xen.org> wrote:
>>
>> On 21/01/2021 17:18, Rahul Singh wrote:
>>> Hello Oleksandr,
>>
>> Hi,
>>
>>>> On 20 Jan 2021, at 9:33 pm, Oleksandr <olekstysh@gmail.com> wrote:
>>>>
>>>>
>>>> On 20.01.21 16:52, Rahul Singh wrote:
>>>>
>>>> Hi Rahul
>>>>
>>>>> Add support for ARM architected SMMUv3 implementation. It is based on
>>>>> the Linux SMMUv3 driver.
>>>>>
>>>>> Driver is currently supported as Tech Preview.
>>>>>
>>>>> Major differences with regard to Linux driver are as follows:
>>>>> 2. Only Stage-2 translation is supported as compared to the Linux driver
>>>>>     that supports both Stage-1 and Stage-2 translations.
>>>>> 3. Use P2M  page table instead of creating one as SMMUv3 has the
>>>>>     capability to share the page tables with the CPU.
>>>>> 4. Tasklets are used in place of threaded IRQ's in Linux for event queue
>>>>>     and priority queue IRQ handling.
>>>>> 5. Latest version of the Linux SMMUv3 code implements the commands queue
>>>>>     access functions based on atomic operations implemented in Linux.
>>>>>     Atomic functions used by the commands queue access functions are not
>>>>>     implemented in XEN therefore we decided to port the earlier version
>>>>>     of the code. Atomic operations are introduced to fix the bottleneck
>>>>>     of the SMMU command queue insertion operation. A new algorithm for
>>>>>     inserting commands into the queue is introduced, which is lock-free
>>>>>     on the fast-path.
>>>>>     Consequence of reverting the patch is that the command queue
>>>>>     insertion will be slow for large systems as spinlock will be used to
>>>>>     serializes accesses from all CPUs to the single queue supported by
>>>>>     the hardware. Once the proper atomic operations will be available in
>>>>>     XEN the driver can be updated.
>>>>> 6. Spin lock is used in place of mutex when attaching a device to the
>>>>>     SMMU, as there is no blocking locks implementation available in XEN.
>>>>>     This might introduce latency in XEN. Need to investigate before
>>>>>     driver is out for tech preview.
>>>>> 7. PCI ATS functionality is not supported, as there is no support
>>>>>     available in XEN to test the functionality. Code is not tested and
>>>>>     compiled. Code is guarded by the flag CONFIG_PCI_ATS.
>>>>> 8. MSI interrupts are not supported as there is no support available in
>>>>>     XEN to request MSI interrupts. Code is not tested and compiled. Code
>>>>>     is guarded by the flag CONFIG_MSI.
>>>>>
>>>>> Signed-off-by: Rahul Singh <rahul.singh@arm.com>
>>>>> ---
>>>>> Changes since v2:
>>>>> - added return statement for readx_poll_timeout function.
>>>>> - remove iommu_get_dma_cookie and iommu_put_dma_cookie.
>>>>> - remove struct arm_smmu_xen_device as not required.
>>>>> - move dt_property_match_string to device_tree.c file.
>>>>> - replace arm_smmu_*_thread to arm_smmu_*_tasklet to avoid confusion.
>>>>> - use ARM_SMMU_REG_SZ as size when map memory to XEN.
>>>>> - remove bypass keyword to make sure when device-tree probe is failed we
>>>>>    are reporting error and not continuing to configure SMMU in bypass
>>>>>    mode.
>>>>> - fixed minor comments.
>>>>> Changes since v3:
>>>>> - Fixed typo for CONFIG_MSI
>>>>> - Added back the mutex code
>>>>> - Rebase the patch on top of newly added WARN_ON().
>>>>> - Remove the direct read of register VTCR_EL2.
>>>>> - Fixed minor comments.
>>>>> Changes since v4:
>>>>> - Replace the ffsll() with ffs64() function.
>>>>> - Add code to free resources when probe failed.
>>>>
>>>> Thank you for addressing, patch looks ok to me, just one small remark below:
>>>>
>>>>
>>>>> +
>>>>> +static void __hwdom_init arm_smmu_iommu_hwdom_init(struct domain *d)
>>>>> +{
>>>>> +}
>>>>
>>>> We discussed in V4 about adding some code here which all IOMMUs on Arm already have, copy it below for the convenience:
>>>>
>>>>
>>>>       /* Set to false options not supported on ARM. */
>>>>       if ( iommu_hwdom_inclusive )
>>>>           printk(XENLOG_WARNING
>>>>           "map-inclusive dom0-iommu option is not supported on ARM\n");
>>>>       iommu_hwdom_inclusive = false;
>>>>       if ( iommu_hwdom_reserved == 1 )
>>>>           printk(XENLOG_WARNING
>>>>           "map-reserved dom0-iommu option is not supported on ARM\n");
>>>>       iommu_hwdom_reserved = 0;
>>>>
>>>>       arch_iommu_hwdom_init(d);
>>>>
>>>>
>>>> Also we discussed about possibility to fold the part of code (which disables unsupported options) in arch_iommu_hwdom_init() to avoid duplication as a follow-up.
>>>> At least, I expected to see arch_iommu_hwdom_init() to be called by arm_smmu_iommu_hwdom_init() it current patch... Please note, this is *not* a request for change immediately,
>>>> I think, driver is functional even without this code (hopefully arch_iommu_hwdom_init is empty now, etc).  But, if you happen to do V6 or probably it could be done on commit ...
>>>>
>>> Yes I will send the patch to move the code to arch_iommu_hwdom_init() to avoid duplication once SMMUv3 driver will be merged.
>>> I thought anyway I have to remove the code from SMMUv1 and IPMMU I will take care of all the IOMMU driver at the same time because of that I didn’t modify the SMMUv3 driver.
>>
>> There are two part in the problem here:
>>   1) Code duplication
>>   2) The SMMUv3 not checking the command line and calling arch_iommu_hwdom_init(d)
>>
>> I agree that 1) can be deferred because it is a clean-up. However, I consider 2) a (latent) bug because it means that we risk unintentionally breaking the SMMUv3 driver is we need to add code in arch_iommu_hwdom_init() as part of a future bug fix for 4.15.
>>
>> Therefore...
>>
>>> Yes if there is a need for v6 I will add the arch_iommu_hwdom_init(d) in arm_smmu_iommu_hwdom_init().
>>
>> ... I think calling arch_iommu_hwdom_init() should be the strict minimum. So please address it. Although, no need to resend the full series, you can only resend patch #10.
> 
> Ok. I agree with you I will send the next version to fix the same.  Please suggest do you want me to check command line also in SMMUv3 now and later remove the code once I will send the patch to move duplicate code.
> 
> ---
> /* Set to false options not supported on ARM. */
>      if ( iommu_hwdom_inclusive )
>          printk(XENLOG_WARNING
>          "map-inclusive dom0-iommu option is not supported on ARM\n");
>      iommu_hwdom_inclusive = false;
>      if ( iommu_hwdom_reserved == 1 )
>          printk(XENLOG_WARNING
>          "map-reserved dom0-iommu option is not supported on ARM\n");
>      iommu_hwdom_reserved = 0;
>                                                                                  
>      arch_iommu_hwdom_init(d);
> 
> --
It should be a copy/paste from the other driver, so it would be nice to 
handle everything now (the code above sounds good).

We can handle the consolition afterwards.

Cheers,


-- 
Julien Grall


^ permalink raw reply	[flat|nested] 24+ messages in thread

* Re: [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver
  2021-01-21 18:43       ` Julien Grall
@ 2021-01-21 20:28         ` Rahul Singh
  2021-01-21 21:20           ` Stefano Stabellini
  0 siblings, 1 reply; 24+ messages in thread
From: Rahul Singh @ 2021-01-21 20:28 UTC (permalink / raw)
  To: Julien Grall
  Cc: Stefano Stabellini, xen-devel, Bertrand Marquis, Andrew Cooper,
	George Dunlap, Ian Jackson, Jan Beulich, Wei Liu, Paul Durrant,
	Volodymyr Babchuk

Hello Julien,

> On 21 Jan 2021, at 6:43 pm, Julien Grall <julien@xen.org> wrote:
> 
> Hi Rahul,
> 
> Please try to trim the e-mail when quoting, otherwise it is quite difficult to find the only couple of answer you wrote.
> 
> On 21/01/2021 17:10, Rahul Singh wrote:
>>> On 20 Jan 2021, at 8:31 pm, Stefano Stabellini <sstabellini@kernel.org> wrote:
>>>> -static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
>>>> -				      resource_size_t size)
>>>> +
>>>> +static void arm_smmu_free_structures(struct arm_smmu_device *smmu)
>>>> {
>>>> -	struct resource res = {
>>>> -		.flags = IORESOURCE_MEM,
>>>> -		.start = start,
>>>> -		.end = start + size - 1,
>>>> -	};
>>>> +	if (smmu->cmdq.q.base)
>>>> +		xfree(smmu->cmdq.q.base);
>>>> +
>>>> +	if (smmu->evtq.q.base)
>>>> +		xfree(smmu->evtq.q.base);
>>>> 
>>>> -	return devm_ioremap_resource(dev, &res);
>>>> +	if (smmu->priq.q.base)
>>>> +		xfree(smmu->priq.q.base);
>>>> +
>>>> +	if (smmu->strtab_cfg.strtab)
>>>> +		xfree(smmu->strtab_cfg.strtab);
>>>> +
>>>> +	if (smmu->strtab_cfg.l1_desc)
>>>> +		xfree(smmu->strtab_cfg.l1_desc);
>>> 
>>> From what I can tell we also need to free somewhere
>>> smmu->strtab_cfg->l1_desc->l2ptr allocated by arm_smmu_init_l2_strtab
>> "l1_desc->l2ptr" is a pointer to the Level 1 Stream Table Descriptor if 2-level Stream Table supported.
>> If the device is protected by IOMMU, SMMUv3 driver will allocate the  "l1_desc->l2ptr” when the device is added to the IOMMU via arm_smmu_add_device() function and device will be configured in bypass/abort mode.
>> Once we assign the device to the domain(arm_smmu_assign_dev() ) smmuv3 hw will be configured correctly to match the StreamID. If there is a failure in assigning the device, that case also XEN will not remove the device and master device still be in bypass/abort mode.
> 
> I am a bit confused with this answer. Wouldn't this mean that we are "leaking" memory if we fail to assign the device?

No we are not leaking memory as "l1_desc->l2ptr” is still be valid and is required for correct SMMUv3 opeation if we fail to assign the device, as in that case device will operate in bypass or abort mode. 

For example if by any chance there is faulty hw behind SMMUv3 then if we fail to assign the device we can configure the device in abort mode in that case SMMUv3 hw will silently report abort to device, without any event recorded.

We can also configure the device in bypass mode if we fail to assign. Thats why I thought not to free the "l1_desc->l2ptr” if we fail to assign the device.

> 
>> As in XEN, there is no function to remove the master device from the IOMMU, because of that I feel there is no need to free the "l1_desc->l2ptr” in case of failure also.
> 
> Hmmm... Xen is able to remove device from the IOMMU. The reason this is not implemented yet on Arm is because you can't hot-unplug "platform" device.
> 
> I expect the removal function to be useful for PCI.

Yes I agree for PCI hot plug devices we have to implement the IOMMU remove function. If we implement the remove function for PCI hot-plug we can free the the "l1_desc->l2ptr” in the remove function for that device. 

Regards,
Rahul
> 
> Cheers,
> 
> -- 
> Julien Grall


^ permalink raw reply	[flat|nested] 24+ messages in thread

* Re: [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver
  2021-01-21 20:28         ` Rahul Singh
@ 2021-01-21 21:20           ` Stefano Stabellini
  0 siblings, 0 replies; 24+ messages in thread
From: Stefano Stabellini @ 2021-01-21 21:20 UTC (permalink / raw)
  To: Rahul Singh
  Cc: Julien Grall, Stefano Stabellini, xen-devel, Bertrand Marquis,
	Andrew Cooper, George Dunlap, Ian Jackson, Jan Beulich, Wei Liu,
	Paul Durrant, Volodymyr Babchuk

[-- Attachment #1: Type: text/plain, Size: 3241 bytes --]

On Thu, 21 Jan 2021, Rahul Singh wrote:
> > On 21 Jan 2021, at 6:43 pm, Julien Grall <julien@xen.org> wrote:
> > On 21/01/2021 17:10, Rahul Singh wrote:
> >>> On 20 Jan 2021, at 8:31 pm, Stefano Stabellini <sstabellini@kernel.org> wrote:
> >>>> -static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
> >>>> -				      resource_size_t size)
> >>>> +
> >>>> +static void arm_smmu_free_structures(struct arm_smmu_device *smmu)
> >>>> {
> >>>> -	struct resource res = {
> >>>> -		.flags = IORESOURCE_MEM,
> >>>> -		.start = start,
> >>>> -		.end = start + size - 1,
> >>>> -	};
> >>>> +	if (smmu->cmdq.q.base)
> >>>> +		xfree(smmu->cmdq.q.base);
> >>>> +
> >>>> +	if (smmu->evtq.q.base)
> >>>> +		xfree(smmu->evtq.q.base);
> >>>> 
> >>>> -	return devm_ioremap_resource(dev, &res);
> >>>> +	if (smmu->priq.q.base)
> >>>> +		xfree(smmu->priq.q.base);
> >>>> +
> >>>> +	if (smmu->strtab_cfg.strtab)
> >>>> +		xfree(smmu->strtab_cfg.strtab);
> >>>> +
> >>>> +	if (smmu->strtab_cfg.l1_desc)
> >>>> +		xfree(smmu->strtab_cfg.l1_desc);
> >>> 
> >>> From what I can tell we also need to free somewhere
> >>> smmu->strtab_cfg->l1_desc->l2ptr allocated by arm_smmu_init_l2_strtab
> >> "l1_desc->l2ptr" is a pointer to the Level 1 Stream Table Descriptor if 2-level Stream Table supported.
> >> If the device is protected by IOMMU, SMMUv3 driver will allocate the  "l1_desc->l2ptr” when the device is added to the IOMMU via arm_smmu_add_device() function and device will be configured in bypass/abort mode.
> >> Once we assign the device to the domain(arm_smmu_assign_dev() ) smmuv3 hw will be configured correctly to match the StreamID. If there is a failure in assigning the device, that case also XEN will not remove the device and master device still be in bypass/abort mode.
> > 
> > I am a bit confused with this answer. Wouldn't this mean that we are "leaking" memory if we fail to assign the device?
> 
> No we are not leaking memory as "l1_desc->l2ptr” is still be valid and is required for correct SMMUv3 opeation if we fail to assign the device, as in that case device will operate in bypass or abort mode. 
> 
> For example if by any chance there is faulty hw behind SMMUv3 then if we fail to assign the device we can configure the device in abort mode in that case SMMUv3 hw will silently report abort to device, without any event recorded.
> 
> We can also configure the device in bypass mode if we fail to assign. Thats why I thought not to free the "l1_desc->l2ptr” if we fail to assign the device.

Basically there are two places where l2ptr should be freed:

1) the error out path (err_free_master) in arm_smmu_add_device
2) arm_smmu_remove_device

However, arm_smmu_remove_device is not actually implementedi at all. In
regards to 1), it would be redundant because the memory allocation of
l2ptr is the last operation that could return an error in
arm_smmu_add_device. In other words, if it fails then the memory is not
allocated.

To avoid future memory-leaks in case we add function calls that could
fail after the arm_smmu_init_l2_strtab() call in arm_smmu_add_device, I
think it would be good to have an xfree(l2ptr) under err_free_master.
But given that it is not necessary today I am OK either way.

^ permalink raw reply	[flat|nested] 24+ messages in thread

end of thread, other threads:[~2021-01-21 21:20 UTC | newest]

Thread overview: 24+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-01-20 14:52 [PATCH v5 00/10] xen/arm: Add support for SMMUv3 driver Rahul Singh
2021-01-20 14:52 ` [PATCH v5 01/10] xen/arm: smmuv3: Import the SMMUv3 driver from Linux Rahul Singh
2021-01-20 14:52 ` [PATCH v5 02/10] xen/arm: Revert atomic operation related command-queue insertion patch Rahul Singh
2021-01-20 14:52 ` [PATCH v5 03/10] xen/arm: smmuv3: Revert patch related to XArray Rahul Singh
2021-01-20 14:52 ` [PATCH v5 04/10] xen/arm: smmuv3: Remove support for Stage-1 translation on SMMUv3 Rahul Singh
2021-01-20 14:52 ` [PATCH v5 05/10] xen/arm: smmuv3: Remove Linux specific code that is not usable in XEN Rahul Singh
2021-01-20 14:52 ` [PATCH v5 06/10] xen/device-tree: Add dt_property_match_string helper Rahul Singh
2021-01-20 14:52 ` [PATCH v5 07/10] xen/compiler: import 'fallthrough' keyword from linux Rahul Singh
2021-01-20 14:52 ` [PATCH v5 08/10] xen/arm: smmuv3: Use fallthrough pseudo-keyword Rahul Singh
2021-01-20 15:36   ` Bertrand Marquis
2021-01-20 19:56   ` Stefano Stabellini
2021-01-20 14:52 ` [PATCH v5 09/10] xen/arm: smmuv3: Replace linux functions with xen functions Rahul Singh
2021-01-20 14:52 ` [PATCH v5 10/10] xen/arm: smmuv3: Add support for SMMUv3 driver Rahul Singh
2021-01-20 15:35   ` Bertrand Marquis
2021-01-20 20:31   ` Stefano Stabellini
2021-01-21 17:10     ` Rahul Singh
2021-01-21 18:43       ` Julien Grall
2021-01-21 20:28         ` Rahul Singh
2021-01-21 21:20           ` Stefano Stabellini
2021-01-20 21:33   ` Oleksandr
2021-01-21 17:18     ` Rahul Singh
2021-01-21 18:31       ` Julien Grall
2021-01-21 18:50         ` Rahul Singh
2021-01-21 20:19           ` Julien Grall

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