* [PATCH kernel 2/2] powerpc/powernv/npu: Move platform shared code to sysdev
2019-01-14 0:55 [PATCH kernel 0/2] powerpc/powernv/npu: Move platform shared code to sysdev Alexey Kardashevskiy
2019-01-14 0:56 ` [PATCH kernel 1/2] powerpc/powernv/npu: Move compound PEs to powernv Alexey Kardashevskiy
@ 2019-01-14 0:56 ` Alexey Kardashevskiy
1 sibling, 0 replies; 3+ messages in thread
From: Alexey Kardashevskiy @ 2019-01-14 0:56 UTC (permalink / raw)
To: linuxppc-dev
Cc: Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan,
Reza Arbab, David Gibson
Initially NPU support was introduced for the powernv platform only,
and later it was extended to pseries so we ended up in a situation when
pseries code calls into arch/powerpc/platforms/powernv which is ugly.
This moves parts of npu-dma.c required for both powernv and pseries
platforms to sysdev.
This is mostly cut-n-paste; the only change is:
the pnv_npu2_init_context() helper takes a callback pointer which
returns void but the empty stub for it defines the callback as it
returns a pointer so this fixes it.
From now on it is possible to build without POWERNV platform enabled and
still have NPU2 support on pseries; currently this fails as:
arch/powerpc/platforms/pseries/pci.o: In function `pSeries_final_fixup':
/home/aik/p/kernel/arch/powerpc/platforms/pseries/pci.c:267: undefined reference to `pnv_npu2_init'
/home/aik/p/kernel/Makefile==1027== recipe for target 'vmlinux' failed
make[1]: *** [vmlinux] Error 1
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
arch/powerpc/sysdev/Makefile | 1 +
arch/powerpc/include/asm/npu.h | 88 +++
arch/powerpc/include/asm/pci.h | 8 +-
arch/powerpc/include/asm/powernv.h | 24 -
arch/powerpc/platforms/powernv/npu-dma.c | 662 ----------------------
arch/powerpc/sysdev/npu.c | 677 +++++++++++++++++++++++
arch/powerpc/sysdev/Kconfig | 3 +
7 files changed, 770 insertions(+), 693 deletions(-)
create mode 100644 arch/powerpc/include/asm/npu.h
create mode 100644 arch/powerpc/sysdev/npu.c
diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile
index aaf2328..e8895e3 100644
--- a/arch/powerpc/sysdev/Makefile
+++ b/arch/powerpc/sysdev/Makefile
@@ -59,3 +59,4 @@ obj-$(CONFIG_PPC_XICS) += xics/
obj-$(CONFIG_PPC_XIVE) += xive/
obj-$(CONFIG_GE_FPGA) += ge/
+obj-$(CONFIG_PPC_NPU) += npu.o
diff --git a/arch/powerpc/include/asm/npu.h b/arch/powerpc/include/asm/npu.h
new file mode 100644
index 0000000..c957472
--- /dev/null
+++ b/arch/powerpc/include/asm/npu.h
@@ -0,0 +1,88 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2019 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _ASM_NPU_H
+#define _ASM_NPU_H
+
+#if defined(CONFIG_PPC_RADIX_MMU) && \
+ (defined(CONFIG_PPC_POWERNV) || defined(CONFIG_PPC_PSERIES))
+#define NPU2_WRITE 1
+extern struct npu_context *pnv_npu2_init_context(struct pci_dev *gpdev,
+ unsigned long flags,
+ void (*cb)(struct npu_context *, void *),
+ void *priv);
+extern void pnv_npu2_destroy_context(struct npu_context *context,
+ struct pci_dev *gpdev);
+extern int pnv_npu2_handle_fault(struct npu_context *context, uintptr_t *ea,
+ unsigned long *flags, unsigned long *status,
+ int count);
+extern int pnv_npu2_init(struct pci_controller *hose);
+extern struct pci_dev *pnv_pci_get_gpu_dev(struct pci_dev *npdev);
+extern struct pci_dev *pnv_pci_get_npu_dev(struct pci_dev *gpdev, int index);
+
+#else
+static inline struct npu_context *pnv_npu2_init_context(struct pci_dev *gpdev,
+ unsigned long flags,
+ void (*cb)(struct npu_context *, void *),
+ void *priv)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline void pnv_npu2_destroy_context(struct npu_context *context,
+ struct pci_dev *gpdev)
+{
+}
+
+static inline int pnv_npu2_handle_fault(struct npu_context *context,
+ uintptr_t *ea, unsigned long *flags,
+ unsigned long *status, int count)
+{
+ return -ENODEV;
+}
+
+static inline int pnv_npu2_init(struct pci_controller *hose)
+{
+ return 0;
+}
+
+static inline struct pci_dev *pnv_pci_get_gpu_dev(struct pci_dev *npdev)
+{
+ return NULL;
+}
+
+static inline struct pci_dev *pnv_pci_get_npu_dev(struct pci_dev *gpdev,
+ int index)
+{
+ return NULL;
+}
+
+#endif
+
+#if defined(CONFIG_PPC_POWERNV)
+extern int pnv_npu2_map_lpar_dev(struct pci_dev *gpdev, unsigned int lparid,
+ unsigned long msr);
+extern int pnv_npu2_unmap_lpar_dev(struct pci_dev *gpdev);
+#else
+static inline int pnv_npu2_map_lpar_dev(struct pci_dev *gpdev,
+ unsigned int lparid, unsigned long msr)
+{
+ return -ENODEV;
+}
+
+static inline int pnv_npu2_unmap_lpar_dev(struct pci_dev *gpdev)
+{
+ return -ENODEV;
+}
+
+
+#endif
+
+#endif /* _ASM_NPU_H */
diff --git a/arch/powerpc/include/asm/pci.h b/arch/powerpc/include/asm/pci.h
index 0c72f18..70a6216 100644
--- a/arch/powerpc/include/asm/pci.h
+++ b/arch/powerpc/include/asm/pci.h
@@ -19,6 +19,7 @@
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pci-bridge.h>
+#include <asm/npu.h>
/* Return values for pci_controller_ops.probe_mode function */
#define PCI_PROBE_NONE -1 /* Don't look at this bus at all */
@@ -127,11 +128,4 @@ extern void pcibios_scan_phb(struct pci_controller *hose);
#endif /* __KERNEL__ */
-extern struct pci_dev *pnv_pci_get_gpu_dev(struct pci_dev *npdev);
-extern struct pci_dev *pnv_pci_get_npu_dev(struct pci_dev *gpdev, int index);
-extern int pnv_npu2_init(struct pci_controller *hose);
-extern int pnv_npu2_map_lpar_dev(struct pci_dev *gpdev, unsigned int lparid,
- unsigned long msr);
-extern int pnv_npu2_unmap_lpar_dev(struct pci_dev *gpdev);
-
#endif /* __ASM_POWERPC_PCI_H */
diff --git a/arch/powerpc/include/asm/powernv.h b/arch/powerpc/include/asm/powernv.h
index 362ea12..fd7522c 100644
--- a/arch/powerpc/include/asm/powernv.h
+++ b/arch/powerpc/include/asm/powernv.h
@@ -11,34 +11,10 @@
#define _ASM_POWERNV_H
#ifdef CONFIG_PPC_POWERNV
-#define NPU2_WRITE 1
extern void powernv_set_nmmu_ptcr(unsigned long ptcr);
-extern struct npu_context *pnv_npu2_init_context(struct pci_dev *gpdev,
- unsigned long flags,
- void (*cb)(struct npu_context *, void *),
- void *priv);
-extern void pnv_npu2_destroy_context(struct npu_context *context,
- struct pci_dev *gpdev);
-extern int pnv_npu2_handle_fault(struct npu_context *context, uintptr_t *ea,
- unsigned long *flags, unsigned long *status,
- int count);
-
void pnv_tm_init(void);
#else
static inline void powernv_set_nmmu_ptcr(unsigned long ptcr) { }
-static inline struct npu_context *pnv_npu2_init_context(struct pci_dev *gpdev,
- unsigned long flags,
- struct npu_context *(*cb)(struct npu_context *, void *),
- void *priv) { return ERR_PTR(-ENODEV); }
-static inline void pnv_npu2_destroy_context(struct npu_context *context,
- struct pci_dev *gpdev) { }
-
-static inline int pnv_npu2_handle_fault(struct npu_context *context,
- uintptr_t *ea, unsigned long *flags,
- unsigned long *status, int count) {
- return -ENODEV;
-}
-
static inline void pnv_tm_init(void) { }
#endif
diff --git a/arch/powerpc/platforms/powernv/npu-dma.c b/arch/powerpc/platforms/powernv/npu-dma.c
index c7cd259..c1c1438 100644
--- a/arch/powerpc/platforms/powernv/npu-dma.c
+++ b/arch/powerpc/platforms/powernv/npu-dma.c
@@ -11,80 +11,14 @@
#include <linux/mmu_notifier.h>
#include <linux/mmu_context.h>
-#include <linux/of.h>
#include <linux/pci.h>
#include <linux/memblock.h>
-#include <linux/sizes.h>
-#include <asm/debugfs.h>
#include <asm/powernv.h>
#include <asm/opal.h>
#include "pci.h"
-/*
- * spinlock to protect initialisation of an npu_context for a particular
- * mm_struct.
- */
-static DEFINE_SPINLOCK(npu_context_lock);
-
-static struct pci_dev *get_pci_dev(struct device_node *dn)
-{
- struct pci_dn *pdn = PCI_DN(dn);
-
- return pci_get_domain_bus_and_slot(pci_domain_nr(pdn->phb->bus),
- pdn->busno, pdn->devfn);
-}
-
-/* Given a NPU device get the associated PCI device. */
-struct pci_dev *pnv_pci_get_gpu_dev(struct pci_dev *npdev)
-{
- struct device_node *dn;
- struct pci_dev *gpdev;
-
- if (WARN_ON(!npdev))
- return NULL;
-
- if (WARN_ON(!npdev->dev.of_node))
- return NULL;
-
- /* Get assoicated PCI device */
- dn = of_parse_phandle(npdev->dev.of_node, "ibm,gpu", 0);
- if (!dn)
- return NULL;
-
- gpdev = get_pci_dev(dn);
- of_node_put(dn);
-
- return gpdev;
-}
-EXPORT_SYMBOL(pnv_pci_get_gpu_dev);
-
-/* Given the real PCI device get a linked NPU device. */
-struct pci_dev *pnv_pci_get_npu_dev(struct pci_dev *gpdev, int index)
-{
- struct device_node *dn;
- struct pci_dev *npdev;
-
- if (WARN_ON(!gpdev))
- return NULL;
-
- /* Not all PCI devices have device-tree nodes */
- if (!gpdev->dev.of_node)
- return NULL;
-
- /* Get assoicated PCI device */
- dn = of_parse_phandle(gpdev->dev.of_node, "ibm,npu", index);
- if (!dn)
- return NULL;
-
- npdev = get_pci_dev(dn);
- of_node_put(dn);
-
- return npdev;
-}
-EXPORT_SYMBOL(pnv_pci_get_npu_dev);
-
/*
* Returns the PE assoicated with the PCI device of the given
* NPU. Returns the linked pci device if pci_dev != NULL.
@@ -340,13 +274,7 @@ static struct iommu_table_group_ops pnv_pci_npu_ops = {
.take_ownership = pnv_npu_take_ownership,
.release_ownership = pnv_npu_release_ownership,
};
-#endif /* !CONFIG_IOMMU_API */
-/*
- * NPU2 ATS
- */
-/* Maximum possible number of ATSD MMIO registers per NPU */
-#define NV_NMMU_ATSD_REGS 8
#define NV_NPU_MAX_PE_NUM 16
/*
@@ -359,20 +287,6 @@ struct npu_comp {
struct pnv_ioda_pe *pe[NV_NPU_MAX_PE_NUM];
};
-/* An NPU descriptor, valid for POWER9 only */
-struct npu {
- int index;
- __be64 *mmio_atsd_regs[NV_NMMU_ATSD_REGS];
- unsigned int mmio_atsd_count;
-
- /* Bitmask for MMIO register usage */
- unsigned long mmio_atsd_usage;
-
- /* Do we need to explicitly flush the nest mmu? */
- bool nmmu_flush;
-};
-
-#ifdef CONFIG_IOMMU_API
static long pnv_npu_peers_create_table_userspace(
struct iommu_table_group *table_group,
int num, __u32 page_shift, __u64 window_size, __u32 levels,
@@ -631,582 +545,6 @@ struct iommu_table_group *pnv_npu_compound_attach(struct pnv_ioda_pe *pe)
}
#endif /* CONFIG_IOMMU_API */
-/* Maximum number of nvlinks per npu */
-#define NV_MAX_LINKS 6
-
-/* Maximum index of npu2 hosts in the system. Always < NV_MAX_NPUS */
-static int max_npu2_index;
-
-struct npu_context {
- struct mm_struct *mm;
- struct pci_dev *npdev[NV_MAX_NPUS][NV_MAX_LINKS];
- struct mmu_notifier mn;
- struct kref kref;
- bool nmmu_flush;
-
- /* Callback to stop translation requests on a given GPU */
- void (*release_cb)(struct npu_context *context, void *priv);
-
- /*
- * Private pointer passed to the above callback for usage by
- * device drivers.
- */
- void *priv;
-};
-
-struct mmio_atsd_reg {
- struct npu *npu;
- int reg;
-};
-
-/*
- * Find a free MMIO ATSD register and mark it in use. Return -ENOSPC
- * if none are available.
- */
-static int get_mmio_atsd_reg(struct npu *npu)
-{
- int i;
-
- for (i = 0; i < npu->mmio_atsd_count; i++) {
- if (!test_bit(i, &npu->mmio_atsd_usage))
- if (!test_and_set_bit_lock(i, &npu->mmio_atsd_usage))
- return i;
- }
-
- return -ENOSPC;
-}
-
-static void put_mmio_atsd_reg(struct npu *npu, int reg)
-{
- clear_bit_unlock(reg, &npu->mmio_atsd_usage);
-}
-
-/* MMIO ATSD register offsets */
-#define XTS_ATSD_LAUNCH 0
-#define XTS_ATSD_AVA 1
-#define XTS_ATSD_STAT 2
-
-static unsigned long get_atsd_launch_val(unsigned long pid, unsigned long psize)
-{
- unsigned long launch = 0;
-
- if (psize == MMU_PAGE_COUNT) {
- /* IS set to invalidate entire matching PID */
- launch |= PPC_BIT(12);
- } else {
- /* AP set to invalidate region of psize */
- launch |= (u64)mmu_get_ap(psize) << PPC_BITLSHIFT(17);
- }
-
- /* PRS set to process-scoped */
- launch |= PPC_BIT(13);
-
- /* PID */
- launch |= pid << PPC_BITLSHIFT(38);
-
- /* Leave "No flush" (bit 39) 0 so every ATSD performs a flush */
-
- return launch;
-}
-
-static void mmio_atsd_regs_write(struct mmio_atsd_reg
- mmio_atsd_reg[NV_MAX_NPUS], unsigned long offset,
- unsigned long val)
-{
- struct npu *npu;
- int i, reg;
-
- for (i = 0; i <= max_npu2_index; i++) {
- reg = mmio_atsd_reg[i].reg;
- if (reg < 0)
- continue;
-
- npu = mmio_atsd_reg[i].npu;
- __raw_writeq_be(val, npu->mmio_atsd_regs[reg] + offset);
- }
-}
-
-static void mmio_invalidate_pid(struct mmio_atsd_reg mmio_atsd_reg[NV_MAX_NPUS],
- unsigned long pid)
-{
- unsigned long launch = get_atsd_launch_val(pid, MMU_PAGE_COUNT);
-
- /* Invalidating the entire process doesn't use a va */
- mmio_atsd_regs_write(mmio_atsd_reg, XTS_ATSD_LAUNCH, launch);
-}
-
-static void mmio_invalidate_range(struct mmio_atsd_reg
- mmio_atsd_reg[NV_MAX_NPUS], unsigned long pid,
- unsigned long start, unsigned long psize)
-{
- unsigned long launch = get_atsd_launch_val(pid, psize);
-
- /* Write all VAs first */
- mmio_atsd_regs_write(mmio_atsd_reg, XTS_ATSD_AVA, start);
-
- /* Issue one barrier for all address writes */
- eieio();
-
- /* Launch */
- mmio_atsd_regs_write(mmio_atsd_reg, XTS_ATSD_LAUNCH, launch);
-}
-
-#define mn_to_npu_context(x) container_of(x, struct npu_context, mn)
-
-static void mmio_invalidate_wait(
- struct mmio_atsd_reg mmio_atsd_reg[NV_MAX_NPUS])
-{
- struct npu *npu;
- int i, reg;
-
- /* Wait for all invalidations to complete */
- for (i = 0; i <= max_npu2_index; i++) {
- if (mmio_atsd_reg[i].reg < 0)
- continue;
-
- /* Wait for completion */
- npu = mmio_atsd_reg[i].npu;
- reg = mmio_atsd_reg[i].reg;
- while (__raw_readq(npu->mmio_atsd_regs[reg] + XTS_ATSD_STAT))
- cpu_relax();
- }
-}
-
-/*
- * Acquires all the address translation shootdown (ATSD) registers required to
- * launch an ATSD on all links this npu_context is active on.
- */
-static void acquire_atsd_reg(struct npu_context *npu_context,
- struct mmio_atsd_reg mmio_atsd_reg[NV_MAX_NPUS])
-{
- int i, j;
- struct npu *npu;
- struct pci_dev *npdev;
-
- for (i = 0; i <= max_npu2_index; i++) {
- mmio_atsd_reg[i].reg = -1;
- for (j = 0; j < NV_MAX_LINKS; j++) {
- /*
- * There are no ordering requirements with respect to
- * the setup of struct npu_context, but to ensure
- * consistent behaviour we need to ensure npdev[][] is
- * only read once.
- */
- npdev = READ_ONCE(npu_context->npdev[i][j]);
- if (!npdev)
- continue;
-
- npu = pci_bus_to_host(npdev->bus)->npu;
- if (!npu)
- continue;
-
- mmio_atsd_reg[i].npu = npu;
- mmio_atsd_reg[i].reg = get_mmio_atsd_reg(npu);
- while (mmio_atsd_reg[i].reg < 0) {
- mmio_atsd_reg[i].reg = get_mmio_atsd_reg(npu);
- cpu_relax();
- }
- break;
- }
- }
-}
-
-/*
- * Release previously acquired ATSD registers. To avoid deadlocks the registers
- * must be released in the same order they were acquired above in
- * acquire_atsd_reg.
- */
-static void release_atsd_reg(struct mmio_atsd_reg mmio_atsd_reg[NV_MAX_NPUS])
-{
- int i;
-
- for (i = 0; i <= max_npu2_index; i++) {
- /*
- * We can't rely on npu_context->npdev[][] being the same here
- * as when acquire_atsd_reg() was called, hence we use the
- * values stored in mmio_atsd_reg during the acquire phase
- * rather than re-reading npdev[][].
- */
- if (mmio_atsd_reg[i].reg < 0)
- continue;
-
- put_mmio_atsd_reg(mmio_atsd_reg[i].npu, mmio_atsd_reg[i].reg);
- }
-}
-
-/*
- * Invalidate a virtual address range
- */
-static void mmio_invalidate(struct npu_context *npu_context,
- unsigned long start, unsigned long size)
-{
- struct mmio_atsd_reg mmio_atsd_reg[NV_MAX_NPUS];
- unsigned long pid = npu_context->mm->context.id;
- unsigned long atsd_start = 0;
- unsigned long end = start + size - 1;
- int atsd_psize = MMU_PAGE_COUNT;
-
- /*
- * Convert the input range into one of the supported sizes. If the range
- * doesn't fit, use the next larger supported size. Invalidation latency
- * is high, so over-invalidation is preferred to issuing multiple
- * invalidates.
- *
- * A 4K page size isn't supported by NPU/GPU ATS, so that case is
- * ignored.
- */
- if (size == SZ_64K) {
- atsd_start = start;
- atsd_psize = MMU_PAGE_64K;
- } else if (ALIGN_DOWN(start, SZ_2M) == ALIGN_DOWN(end, SZ_2M)) {
- atsd_start = ALIGN_DOWN(start, SZ_2M);
- atsd_psize = MMU_PAGE_2M;
- } else if (ALIGN_DOWN(start, SZ_1G) == ALIGN_DOWN(end, SZ_1G)) {
- atsd_start = ALIGN_DOWN(start, SZ_1G);
- atsd_psize = MMU_PAGE_1G;
- }
-
- if (npu_context->nmmu_flush)
- /*
- * Unfortunately the nest mmu does not support flushing specific
- * addresses so we have to flush the whole mm once before
- * shooting down the GPU translation.
- */
- flush_all_mm(npu_context->mm);
-
- /*
- * Loop over all the NPUs this process is active on and launch
- * an invalidate.
- */
- acquire_atsd_reg(npu_context, mmio_atsd_reg);
-
- if (atsd_psize == MMU_PAGE_COUNT)
- mmio_invalidate_pid(mmio_atsd_reg, pid);
- else
- mmio_invalidate_range(mmio_atsd_reg, pid, atsd_start,
- atsd_psize);
-
- mmio_invalidate_wait(mmio_atsd_reg);
-
- /*
- * The GPU requires two flush ATSDs to ensure all entries have been
- * flushed. We use PID 0 as it will never be used for a process on the
- * GPU.
- */
- mmio_invalidate_pid(mmio_atsd_reg, 0);
- mmio_invalidate_wait(mmio_atsd_reg);
- mmio_invalidate_pid(mmio_atsd_reg, 0);
- mmio_invalidate_wait(mmio_atsd_reg);
-
- release_atsd_reg(mmio_atsd_reg);
-}
-
-static void pnv_npu2_mn_release(struct mmu_notifier *mn,
- struct mm_struct *mm)
-{
- struct npu_context *npu_context = mn_to_npu_context(mn);
-
- /* Call into device driver to stop requests to the NMMU */
- if (npu_context->release_cb)
- npu_context->release_cb(npu_context, npu_context->priv);
-
- /*
- * There should be no more translation requests for this PID, but we
- * need to ensure any entries for it are removed from the TLB.
- */
- mmio_invalidate(npu_context, 0, ~0UL);
-}
-
-static void pnv_npu2_mn_change_pte(struct mmu_notifier *mn,
- struct mm_struct *mm,
- unsigned long address,
- pte_t pte)
-{
- struct npu_context *npu_context = mn_to_npu_context(mn);
- mmio_invalidate(npu_context, address, PAGE_SIZE);
-}
-
-static void pnv_npu2_mn_invalidate_range(struct mmu_notifier *mn,
- struct mm_struct *mm,
- unsigned long start, unsigned long end)
-{
- struct npu_context *npu_context = mn_to_npu_context(mn);
- mmio_invalidate(npu_context, start, end - start);
-}
-
-static const struct mmu_notifier_ops nv_nmmu_notifier_ops = {
- .release = pnv_npu2_mn_release,
- .change_pte = pnv_npu2_mn_change_pte,
- .invalidate_range = pnv_npu2_mn_invalidate_range,
-};
-
-/*
- * Call into OPAL to setup the nmmu context for the current task in
- * the NPU. This must be called to setup the context tables before the
- * GPU issues ATRs. pdev should be a pointed to PCIe GPU device.
- *
- * A release callback should be registered to allow a device driver to
- * be notified that it should not launch any new translation requests
- * as the final TLB invalidate is about to occur.
- *
- * Returns an error if there no contexts are currently available or a
- * npu_context which should be passed to pnv_npu2_handle_fault().
- *
- * mmap_sem must be held in write mode and must not be called from interrupt
- * context.
- */
-struct npu_context *pnv_npu2_init_context(struct pci_dev *gpdev,
- unsigned long flags,
- void (*cb)(struct npu_context *, void *),
- void *priv)
-{
- int rc;
- u32 nvlink_index;
- struct device_node *nvlink_dn;
- struct mm_struct *mm = current->mm;
- struct npu *npu;
- struct npu_context *npu_context;
- struct pci_controller *hose;
-
- /*
- * At present we don't support GPUs connected to multiple NPUs and I'm
- * not sure the hardware does either.
- */
- struct pci_dev *npdev = pnv_pci_get_npu_dev(gpdev, 0);
-
- if (!npdev)
- /* No nvlink associated with this GPU device */
- return ERR_PTR(-ENODEV);
-
- /* We only support DR/PR/HV in pnv_npu2_map_lpar_dev() */
- if (flags & ~(MSR_DR | MSR_PR | MSR_HV))
- return ERR_PTR(-EINVAL);
-
- nvlink_dn = of_parse_phandle(npdev->dev.of_node, "ibm,nvlink", 0);
- if (WARN_ON(of_property_read_u32(nvlink_dn, "ibm,npu-link-index",
- &nvlink_index)))
- return ERR_PTR(-ENODEV);
-
- if (!mm || mm->context.id == 0) {
- /*
- * Kernel thread contexts are not supported and context id 0 is
- * reserved on the GPU.
- */
- return ERR_PTR(-EINVAL);
- }
-
- hose = pci_bus_to_host(npdev->bus);
- npu = hose->npu;
- if (!npu)
- return ERR_PTR(-ENODEV);
-
- /*
- * We store the npu pci device so we can more easily get at the
- * associated npus.
- */
- spin_lock(&npu_context_lock);
- npu_context = mm->context.npu_context;
- if (npu_context) {
- if (npu_context->release_cb != cb ||
- npu_context->priv != priv) {
- spin_unlock(&npu_context_lock);
- return ERR_PTR(-EINVAL);
- }
-
- WARN_ON(!kref_get_unless_zero(&npu_context->kref));
- }
- spin_unlock(&npu_context_lock);
-
- if (!npu_context) {
- /*
- * We can set up these fields without holding the
- * npu_context_lock as the npu_context hasn't been returned to
- * the caller meaning it can't be destroyed. Parallel allocation
- * is protected against by mmap_sem.
- */
- rc = -ENOMEM;
- npu_context = kzalloc(sizeof(struct npu_context), GFP_KERNEL);
- if (npu_context) {
- kref_init(&npu_context->kref);
- npu_context->mm = mm;
- npu_context->mn.ops = &nv_nmmu_notifier_ops;
- rc = __mmu_notifier_register(&npu_context->mn, mm);
- }
-
- if (rc) {
- kfree(npu_context);
- return ERR_PTR(rc);
- }
-
- mm->context.npu_context = npu_context;
- }
-
- npu_context->release_cb = cb;
- npu_context->priv = priv;
-
- /*
- * npdev is a pci_dev pointer setup by the PCI code. We assign it to
- * npdev[][] to indicate to the mmu notifiers that an invalidation
- * should also be sent over this nvlink. The notifiers don't use any
- * other fields in npu_context, so we just need to ensure that when they
- * deference npu_context->npdev[][] it is either a valid pointer or
- * NULL.
- */
- WRITE_ONCE(npu_context->npdev[npu->index][nvlink_index], npdev);
-
- if (!npu->nmmu_flush) {
- /*
- * If we're not explicitly flushing ourselves we need to mark
- * the thread for global flushes
- */
- npu_context->nmmu_flush = false;
- mm_context_add_copro(mm);
- } else
- npu_context->nmmu_flush = true;
-
- return npu_context;
-}
-EXPORT_SYMBOL(pnv_npu2_init_context);
-
-static void pnv_npu2_release_context(struct kref *kref)
-{
- struct npu_context *npu_context =
- container_of(kref, struct npu_context, kref);
-
- if (!npu_context->nmmu_flush)
- mm_context_remove_copro(npu_context->mm);
-
- npu_context->mm->context.npu_context = NULL;
-}
-
-/*
- * Destroy a context on the given GPU. May free the npu_context if it is no
- * longer active on any GPUs. Must not be called from interrupt context.
- */
-void pnv_npu2_destroy_context(struct npu_context *npu_context,
- struct pci_dev *gpdev)
-{
- int removed;
- struct npu *npu;
- struct pci_dev *npdev = pnv_pci_get_npu_dev(gpdev, 0);
- struct device_node *nvlink_dn;
- u32 nvlink_index;
- struct pci_controller *hose;
-
- if (WARN_ON(!npdev))
- return;
-
- hose = pci_bus_to_host(npdev->bus);
- npu = hose->npu;
- if (!npu)
- return;
- nvlink_dn = of_parse_phandle(npdev->dev.of_node, "ibm,nvlink", 0);
- if (WARN_ON(of_property_read_u32(nvlink_dn, "ibm,npu-link-index",
- &nvlink_index)))
- return;
- WRITE_ONCE(npu_context->npdev[npu->index][nvlink_index], NULL);
- spin_lock(&npu_context_lock);
- removed = kref_put(&npu_context->kref, pnv_npu2_release_context);
- spin_unlock(&npu_context_lock);
-
- /*
- * We need to do this outside of pnv_npu2_release_context so that it is
- * outside the spinlock as mmu_notifier_destroy uses SRCU.
- */
- if (removed) {
- mmu_notifier_unregister(&npu_context->mn,
- npu_context->mm);
-
- kfree(npu_context);
- }
-
-}
-EXPORT_SYMBOL(pnv_npu2_destroy_context);
-
-/*
- * Assumes mmap_sem is held for the contexts associated mm.
- */
-int pnv_npu2_handle_fault(struct npu_context *context, uintptr_t *ea,
- unsigned long *flags, unsigned long *status, int count)
-{
- u64 rc = 0, result = 0;
- int i, is_write;
- struct page *page[1];
- const char __user *u;
- char c;
-
- /* mmap_sem should be held so the struct_mm must be present */
- struct mm_struct *mm = context->mm;
-
- WARN_ON(!rwsem_is_locked(&mm->mmap_sem));
-
- for (i = 0; i < count; i++) {
- is_write = flags[i] & NPU2_WRITE;
- rc = get_user_pages_remote(NULL, mm, ea[i], 1,
- is_write ? FOLL_WRITE : 0,
- page, NULL, NULL);
-
- if (rc != 1) {
- status[i] = rc;
- result = -EFAULT;
- continue;
- }
-
- /* Make sure partition scoped tree gets a pte */
- u = page_address(page[0]);
- if (__get_user(c, u))
- result = -EFAULT;
-
- status[i] = 0;
- put_page(page[0]);
- }
-
- return result;
-}
-EXPORT_SYMBOL(pnv_npu2_handle_fault);
-
-int pnv_npu2_init(struct pci_controller *hose)
-{
- unsigned int i;
- u64 mmio_atsd;
- static int npu_index;
- struct npu *npu;
- int ret;
-
- npu = kzalloc(sizeof(*npu), GFP_KERNEL);
- if (!npu)
- return -ENOMEM;
-
- npu->nmmu_flush = of_property_read_bool(hose->dn, "ibm,nmmu-flush");
-
- for (i = 0; i < ARRAY_SIZE(npu->mmio_atsd_regs) &&
- !of_property_read_u64_index(hose->dn, "ibm,mmio-atsd",
- i, &mmio_atsd); i++)
- npu->mmio_atsd_regs[i] = ioremap(mmio_atsd, 32);
-
- pr_info("NPU%d: Found %d MMIO ATSD registers", hose->global_number, i);
- npu->mmio_atsd_count = i;
- npu->mmio_atsd_usage = 0;
- npu_index++;
- if (WARN_ON(npu_index >= NV_MAX_NPUS)) {
- ret = -ENOSPC;
- goto fail_exit;
- }
- max_npu2_index = npu_index;
- npu->index = npu_index;
- hose->npu = npu;
-
- return 0;
-
-fail_exit:
- for (i = 0; i < npu->mmio_atsd_count; ++i)
- iounmap(npu->mmio_atsd_regs[i]);
-
- kfree(npu);
-
- return ret;
-}
-
int pnv_npu2_map_lpar_dev(struct pci_dev *gpdev, unsigned int lparid,
unsigned long msr)
{
diff --git a/arch/powerpc/sysdev/npu.c b/arch/powerpc/sysdev/npu.c
new file mode 100644
index 0000000..72755b2
--- /dev/null
+++ b/arch/powerpc/sysdev/npu.c
@@ -0,0 +1,677 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * This file implements the context manipulation for NVLink devices.
+ *
+ * Copyright IBM Corporation 2019.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * Copied from original arch/powerpc/platforms/powernv/npu-dma.c:
+ * Copyright Alistair Popple, IBM Corporation 2015.
+ */
+
+#include <linux/mmu_notifier.h>
+#include <linux/mmu_context.h>
+#include <linux/pci.h>
+
+/*
+ * NPU2 ATS
+ */
+/* Maximum possible number of ATSD MMIO registers per NPU */
+#define NV_NMMU_ATSD_REGS 8
+
+/* An NPU descriptor, valid for POWER9 only */
+struct npu {
+ int index;
+ __be64 *mmio_atsd_regs[NV_NMMU_ATSD_REGS];
+ unsigned int mmio_atsd_count;
+
+ /* Bitmask for MMIO register usage */
+ unsigned long mmio_atsd_usage;
+
+ /* Do we need to explicitly flush the nest mmu? */
+ bool nmmu_flush;
+};
+
+/*
+ * spinlock to protect initialisation of an npu_context for a particular
+ * mm_struct.
+ */
+static DEFINE_SPINLOCK(npu_context_lock);
+
+static struct pci_dev *get_pci_dev(struct device_node *dn)
+{
+ struct pci_dn *pdn = PCI_DN(dn);
+
+ return pci_get_domain_bus_and_slot(pci_domain_nr(pdn->phb->bus),
+ pdn->busno, pdn->devfn);
+}
+
+/* Given a NPU device get the associated PCI device. */
+struct pci_dev *pnv_pci_get_gpu_dev(struct pci_dev *npdev)
+{
+ struct device_node *dn;
+ struct pci_dev *gpdev;
+
+ if (WARN_ON(!npdev))
+ return NULL;
+
+ if (WARN_ON(!npdev->dev.of_node))
+ return NULL;
+
+ /* Get assoicated PCI device */
+ dn = of_parse_phandle(npdev->dev.of_node, "ibm,gpu", 0);
+ if (!dn)
+ return NULL;
+
+ gpdev = get_pci_dev(dn);
+ of_node_put(dn);
+
+ return gpdev;
+}
+EXPORT_SYMBOL(pnv_pci_get_gpu_dev);
+
+/* Given the real PCI device get a linked NPU device. */
+struct pci_dev *pnv_pci_get_npu_dev(struct pci_dev *gpdev, int index)
+{
+ struct device_node *dn;
+ struct pci_dev *npdev;
+
+ if (WARN_ON(!gpdev))
+ return NULL;
+
+ /* Not all PCI devices have device-tree nodes */
+ if (!gpdev->dev.of_node)
+ return NULL;
+
+ /* Get assoicated PCI device */
+ dn = of_parse_phandle(gpdev->dev.of_node, "ibm,npu", index);
+ if (!dn)
+ return NULL;
+
+ npdev = get_pci_dev(dn);
+ of_node_put(dn);
+
+ return npdev;
+}
+EXPORT_SYMBOL(pnv_pci_get_npu_dev);
+
+/* Maximum number of nvlinks per npu */
+#define NV_MAX_LINKS 6
+
+/* Maximum index of npu2 hosts in the system. Always < NV_MAX_NPUS */
+static int max_npu2_index;
+
+struct npu_context {
+ struct mm_struct *mm;
+ struct pci_dev *npdev[NV_MAX_NPUS][NV_MAX_LINKS];
+ struct mmu_notifier mn;
+ struct kref kref;
+ bool nmmu_flush;
+
+ /* Callback to stop translation requests on a given GPU */
+ void (*release_cb)(struct npu_context *context, void *priv);
+
+ /*
+ * Private pointer passed to the above callback for usage by
+ * device drivers.
+ */
+ void *priv;
+};
+
+struct mmio_atsd_reg {
+ struct npu *npu;
+ int reg;
+};
+
+/*
+ * Find a free MMIO ATSD register and mark it in use. Return -ENOSPC
+ * if none are available.
+ */
+static int get_mmio_atsd_reg(struct npu *npu)
+{
+ int i;
+
+ for (i = 0; i < npu->mmio_atsd_count; i++) {
+ if (!test_bit(i, &npu->mmio_atsd_usage))
+ if (!test_and_set_bit_lock(i, &npu->mmio_atsd_usage))
+ return i;
+ }
+
+ return -ENOSPC;
+}
+
+static void put_mmio_atsd_reg(struct npu *npu, int reg)
+{
+ clear_bit_unlock(reg, &npu->mmio_atsd_usage);
+}
+
+/* MMIO ATSD register offsets */
+#define XTS_ATSD_LAUNCH 0
+#define XTS_ATSD_AVA 1
+#define XTS_ATSD_STAT 2
+
+static unsigned long get_atsd_launch_val(unsigned long pid, unsigned long psize)
+{
+ unsigned long launch = 0;
+
+ if (psize == MMU_PAGE_COUNT) {
+ /* IS set to invalidate entire matching PID */
+ launch |= PPC_BIT(12);
+ } else {
+ /* AP set to invalidate region of psize */
+ launch |= (u64)mmu_get_ap(psize) << PPC_BITLSHIFT(17);
+ }
+
+ /* PRS set to process-scoped */
+ launch |= PPC_BIT(13);
+
+ /* PID */
+ launch |= pid << PPC_BITLSHIFT(38);
+
+ /* Leave "No flush" (bit 39) 0 so every ATSD performs a flush */
+
+ return launch;
+}
+
+static void mmio_atsd_regs_write(struct mmio_atsd_reg
+ mmio_atsd_reg[NV_MAX_NPUS], unsigned long offset,
+ unsigned long val)
+{
+ struct npu *npu;
+ int i, reg;
+
+ for (i = 0; i <= max_npu2_index; i++) {
+ reg = mmio_atsd_reg[i].reg;
+ if (reg < 0)
+ continue;
+
+ npu = mmio_atsd_reg[i].npu;
+ __raw_writeq_be(val, npu->mmio_atsd_regs[reg] + offset);
+ }
+}
+
+static void mmio_invalidate_pid(struct mmio_atsd_reg mmio_atsd_reg[NV_MAX_NPUS],
+ unsigned long pid)
+{
+ unsigned long launch = get_atsd_launch_val(pid, MMU_PAGE_COUNT);
+
+ /* Invalidating the entire process doesn't use a va */
+ mmio_atsd_regs_write(mmio_atsd_reg, XTS_ATSD_LAUNCH, launch);
+}
+
+static void mmio_invalidate_range(struct mmio_atsd_reg
+ mmio_atsd_reg[NV_MAX_NPUS], unsigned long pid,
+ unsigned long start, unsigned long psize)
+{
+ unsigned long launch = get_atsd_launch_val(pid, psize);
+
+ /* Write all VAs first */
+ mmio_atsd_regs_write(mmio_atsd_reg, XTS_ATSD_AVA, start);
+
+ /* Issue one barrier for all address writes */
+ eieio();
+
+ /* Launch */
+ mmio_atsd_regs_write(mmio_atsd_reg, XTS_ATSD_LAUNCH, launch);
+}
+
+#define mn_to_npu_context(x) container_of(x, struct npu_context, mn)
+
+static void mmio_invalidate_wait(
+ struct mmio_atsd_reg mmio_atsd_reg[NV_MAX_NPUS])
+{
+ struct npu *npu;
+ int i, reg;
+
+ /* Wait for all invalidations to complete */
+ for (i = 0; i <= max_npu2_index; i++) {
+ if (mmio_atsd_reg[i].reg < 0)
+ continue;
+
+ /* Wait for completion */
+ npu = mmio_atsd_reg[i].npu;
+ reg = mmio_atsd_reg[i].reg;
+ while (__raw_readq(npu->mmio_atsd_regs[reg] + XTS_ATSD_STAT))
+ cpu_relax();
+ }
+}
+
+/*
+ * Acquires all the address translation shootdown (ATSD) registers required to
+ * launch an ATSD on all links this npu_context is active on.
+ */
+static void acquire_atsd_reg(struct npu_context *npu_context,
+ struct mmio_atsd_reg mmio_atsd_reg[NV_MAX_NPUS])
+{
+ int i, j;
+ struct npu *npu;
+ struct pci_dev *npdev;
+
+ for (i = 0; i <= max_npu2_index; i++) {
+ mmio_atsd_reg[i].reg = -1;
+ for (j = 0; j < NV_MAX_LINKS; j++) {
+ /*
+ * There are no ordering requirements with respect to
+ * the setup of struct npu_context, but to ensure
+ * consistent behaviour we need to ensure npdev[][] is
+ * only read once.
+ */
+ npdev = READ_ONCE(npu_context->npdev[i][j]);
+ if (!npdev)
+ continue;
+
+ npu = pci_bus_to_host(npdev->bus)->npu;
+ if (!npu)
+ continue;
+
+ mmio_atsd_reg[i].npu = npu;
+ mmio_atsd_reg[i].reg = get_mmio_atsd_reg(npu);
+ while (mmio_atsd_reg[i].reg < 0) {
+ mmio_atsd_reg[i].reg = get_mmio_atsd_reg(npu);
+ cpu_relax();
+ }
+ break;
+ }
+ }
+}
+
+/*
+ * Release previously acquired ATSD registers. To avoid deadlocks the registers
+ * must be released in the same order they were acquired above in
+ * acquire_atsd_reg.
+ */
+static void release_atsd_reg(struct mmio_atsd_reg mmio_atsd_reg[NV_MAX_NPUS])
+{
+ int i;
+
+ for (i = 0; i <= max_npu2_index; i++) {
+ /*
+ * We can't rely on npu_context->npdev[][] being the same here
+ * as when acquire_atsd_reg() was called, hence we use the
+ * values stored in mmio_atsd_reg during the acquire phase
+ * rather than re-reading npdev[][].
+ */
+ if (mmio_atsd_reg[i].reg < 0)
+ continue;
+
+ put_mmio_atsd_reg(mmio_atsd_reg[i].npu, mmio_atsd_reg[i].reg);
+ }
+}
+
+/*
+ * Invalidate a virtual address range
+ */
+static void mmio_invalidate(struct npu_context *npu_context,
+ unsigned long start, unsigned long size)
+{
+ struct mmio_atsd_reg mmio_atsd_reg[NV_MAX_NPUS];
+ unsigned long pid = npu_context->mm->context.id;
+ unsigned long atsd_start = 0;
+ unsigned long end = start + size - 1;
+ int atsd_psize = MMU_PAGE_COUNT;
+
+ /*
+ * Convert the input range into one of the supported sizes. If the range
+ * doesn't fit, use the next larger supported size. Invalidation latency
+ * is high, so over-invalidation is preferred to issuing multiple
+ * invalidates.
+ *
+ * A 4K page size isn't supported by NPU/GPU ATS, so that case is
+ * ignored.
+ */
+ if (size == SZ_64K) {
+ atsd_start = start;
+ atsd_psize = MMU_PAGE_64K;
+ } else if (ALIGN_DOWN(start, SZ_2M) == ALIGN_DOWN(end, SZ_2M)) {
+ atsd_start = ALIGN_DOWN(start, SZ_2M);
+ atsd_psize = MMU_PAGE_2M;
+ } else if (ALIGN_DOWN(start, SZ_1G) == ALIGN_DOWN(end, SZ_1G)) {
+ atsd_start = ALIGN_DOWN(start, SZ_1G);
+ atsd_psize = MMU_PAGE_1G;
+ }
+
+ if (npu_context->nmmu_flush)
+ /*
+ * Unfortunately the nest mmu does not support flushing specific
+ * addresses so we have to flush the whole mm once before
+ * shooting down the GPU translation.
+ */
+ flush_all_mm(npu_context->mm);
+
+ /*
+ * Loop over all the NPUs this process is active on and launch
+ * an invalidate.
+ */
+ acquire_atsd_reg(npu_context, mmio_atsd_reg);
+
+ if (atsd_psize == MMU_PAGE_COUNT)
+ mmio_invalidate_pid(mmio_atsd_reg, pid);
+ else
+ mmio_invalidate_range(mmio_atsd_reg, pid, atsd_start,
+ atsd_psize);
+
+ mmio_invalidate_wait(mmio_atsd_reg);
+
+ /*
+ * The GPU requires two flush ATSDs to ensure all entries have been
+ * flushed. We use PID 0 as it will never be used for a process on the
+ * GPU.
+ */
+ mmio_invalidate_pid(mmio_atsd_reg, 0);
+ mmio_invalidate_wait(mmio_atsd_reg);
+ mmio_invalidate_pid(mmio_atsd_reg, 0);
+ mmio_invalidate_wait(mmio_atsd_reg);
+
+ release_atsd_reg(mmio_atsd_reg);
+}
+
+static void pnv_npu2_mn_release(struct mmu_notifier *mn,
+ struct mm_struct *mm)
+{
+ struct npu_context *npu_context = mn_to_npu_context(mn);
+
+ /* Call into device driver to stop requests to the NMMU */
+ if (npu_context->release_cb)
+ npu_context->release_cb(npu_context, npu_context->priv);
+
+ /*
+ * There should be no more translation requests for this PID, but we
+ * need to ensure any entries for it are removed from the TLB.
+ */
+ mmio_invalidate(npu_context, 0, ~0UL);
+}
+
+static void pnv_npu2_mn_change_pte(struct mmu_notifier *mn,
+ struct mm_struct *mm,
+ unsigned long address,
+ pte_t pte)
+{
+ struct npu_context *npu_context = mn_to_npu_context(mn);
+
+ mmio_invalidate(npu_context, address, PAGE_SIZE);
+}
+
+static void pnv_npu2_mn_invalidate_range(struct mmu_notifier *mn,
+ struct mm_struct *mm,
+ unsigned long start, unsigned long end)
+{
+ struct npu_context *npu_context = mn_to_npu_context(mn);
+
+ mmio_invalidate(npu_context, start, end - start);
+}
+
+static const struct mmu_notifier_ops nv_nmmu_notifier_ops = {
+ .release = pnv_npu2_mn_release,
+ .change_pte = pnv_npu2_mn_change_pte,
+ .invalidate_range = pnv_npu2_mn_invalidate_range,
+};
+
+/*
+ * Call into OPAL to setup the nmmu context for the current task in
+ * the NPU. This must be called to setup the context tables before the
+ * GPU issues ATRs. pdev should be a pointed to PCIe GPU device.
+ *
+ * A release callback should be registered to allow a device driver to
+ * be notified that it should not launch any new translation requests
+ * as the final TLB invalidate is about to occur.
+ *
+ * Returns an error if there no contexts are currently available or a
+ * npu_context which should be passed to pnv_npu2_handle_fault().
+ *
+ * mmap_sem must be held in write mode and must not be called from interrupt
+ * context.
+ */
+struct npu_context *pnv_npu2_init_context(struct pci_dev *gpdev,
+ unsigned long flags,
+ void (*cb)(struct npu_context *, void *),
+ void *priv)
+{
+ int rc;
+ u32 nvlink_index;
+ struct device_node *nvlink_dn;
+ struct mm_struct *mm = current->mm;
+ struct npu *npu;
+ struct npu_context *npu_context;
+ struct pci_controller *hose;
+
+ /*
+ * At present we don't support GPUs connected to multiple NPUs and I'm
+ * not sure the hardware does either.
+ */
+ struct pci_dev *npdev = pnv_pci_get_npu_dev(gpdev, 0);
+
+ if (!npdev)
+ /* No nvlink associated with this GPU device */
+ return ERR_PTR(-ENODEV);
+
+ /* We only support DR/PR/HV in pnv_npu2_map_lpar_dev() */
+ if (flags & ~(MSR_DR | MSR_PR | MSR_HV))
+ return ERR_PTR(-EINVAL);
+
+ nvlink_dn = of_parse_phandle(npdev->dev.of_node, "ibm,nvlink", 0);
+ if (WARN_ON(of_property_read_u32(nvlink_dn, "ibm,npu-link-index",
+ &nvlink_index)))
+ return ERR_PTR(-ENODEV);
+
+ if (!mm || mm->context.id == 0) {
+ /*
+ * Kernel thread contexts are not supported and context id 0 is
+ * reserved on the GPU.
+ */
+ return ERR_PTR(-EINVAL);
+ }
+
+ hose = pci_bus_to_host(npdev->bus);
+ npu = hose->npu;
+ if (!npu)
+ return ERR_PTR(-ENODEV);
+
+ /*
+ * We store the npu pci device so we can more easily get at the
+ * associated npus.
+ */
+ spin_lock(&npu_context_lock);
+ npu_context = mm->context.npu_context;
+ if (npu_context) {
+ if (npu_context->release_cb != cb ||
+ npu_context->priv != priv) {
+ spin_unlock(&npu_context_lock);
+ return ERR_PTR(-EINVAL);
+ }
+
+ WARN_ON(!kref_get_unless_zero(&npu_context->kref));
+ }
+ spin_unlock(&npu_context_lock);
+
+ if (!npu_context) {
+ /*
+ * We can set up these fields without holding the
+ * npu_context_lock as the npu_context hasn't been returned to
+ * the caller meaning it can't be destroyed. Parallel allocation
+ * is protected against by mmap_sem.
+ */
+ rc = -ENOMEM;
+ npu_context = kzalloc(sizeof(struct npu_context), GFP_KERNEL);
+ if (npu_context) {
+ kref_init(&npu_context->kref);
+ npu_context->mm = mm;
+ npu_context->mn.ops = &nv_nmmu_notifier_ops;
+ rc = __mmu_notifier_register(&npu_context->mn, mm);
+ }
+
+ if (rc) {
+ kfree(npu_context);
+ return ERR_PTR(rc);
+ }
+
+ mm->context.npu_context = npu_context;
+ }
+
+ npu_context->release_cb = cb;
+ npu_context->priv = priv;
+
+ /*
+ * npdev is a pci_dev pointer setup by the PCI code. We assign it to
+ * npdev[][] to indicate to the mmu notifiers that an invalidation
+ * should also be sent over this nvlink. The notifiers don't use any
+ * other fields in npu_context, so we just need to ensure that when they
+ * deference npu_context->npdev[][] it is either a valid pointer or
+ * NULL.
+ */
+ WRITE_ONCE(npu_context->npdev[npu->index][nvlink_index], npdev);
+
+ if (!npu->nmmu_flush) {
+ /*
+ * If we're not explicitly flushing ourselves we need to mark
+ * the thread for global flushes
+ */
+ npu_context->nmmu_flush = false;
+ mm_context_add_copro(mm);
+ } else
+ npu_context->nmmu_flush = true;
+
+ return npu_context;
+}
+EXPORT_SYMBOL(pnv_npu2_init_context);
+
+static void pnv_npu2_release_context(struct kref *kref)
+{
+ struct npu_context *npu_context =
+ container_of(kref, struct npu_context, kref);
+
+ if (!npu_context->nmmu_flush)
+ mm_context_remove_copro(npu_context->mm);
+
+ npu_context->mm->context.npu_context = NULL;
+}
+
+/*
+ * Destroy a context on the given GPU. May free the npu_context if it is no
+ * longer active on any GPUs. Must not be called from interrupt context.
+ */
+void pnv_npu2_destroy_context(struct npu_context *npu_context,
+ struct pci_dev *gpdev)
+{
+ int removed;
+ struct npu *npu;
+ struct pci_dev *npdev = pnv_pci_get_npu_dev(gpdev, 0);
+ struct device_node *nvlink_dn;
+ u32 nvlink_index;
+ struct pci_controller *hose;
+
+ if (WARN_ON(!npdev))
+ return;
+
+ hose = pci_bus_to_host(npdev->bus);
+ npu = hose->npu;
+ if (!npu)
+ return;
+ nvlink_dn = of_parse_phandle(npdev->dev.of_node, "ibm,nvlink", 0);
+ if (WARN_ON(of_property_read_u32(nvlink_dn, "ibm,npu-link-index",
+ &nvlink_index)))
+ return;
+ WRITE_ONCE(npu_context->npdev[npu->index][nvlink_index], NULL);
+ spin_lock(&npu_context_lock);
+ removed = kref_put(&npu_context->kref, pnv_npu2_release_context);
+ spin_unlock(&npu_context_lock);
+
+ /*
+ * We need to do this outside of pnv_npu2_release_context so that it is
+ * outside the spinlock as mmu_notifier_destroy uses SRCU.
+ */
+ if (removed) {
+ mmu_notifier_unregister(&npu_context->mn,
+ npu_context->mm);
+
+ kfree(npu_context);
+ }
+
+}
+EXPORT_SYMBOL(pnv_npu2_destroy_context);
+
+/*
+ * Assumes mmap_sem is held for the contexts associated mm.
+ */
+int pnv_npu2_handle_fault(struct npu_context *context, uintptr_t *ea,
+ unsigned long *flags, unsigned long *status, int count)
+{
+ u64 rc = 0, result = 0;
+ int i, is_write;
+ struct page *page[1];
+ const char __user *u;
+ char c;
+
+ /* mmap_sem should be held so the struct_mm must be present */
+ struct mm_struct *mm = context->mm;
+
+ WARN_ON(!rwsem_is_locked(&mm->mmap_sem));
+
+ for (i = 0; i < count; i++) {
+ is_write = flags[i] & NPU2_WRITE;
+ rc = get_user_pages_remote(NULL, mm, ea[i], 1,
+ is_write ? FOLL_WRITE : 0,
+ page, NULL, NULL);
+
+ if (rc != 1) {
+ status[i] = rc;
+ result = -EFAULT;
+ continue;
+ }
+
+ /* Make sure partition scoped tree gets a pte */
+ u = page_address(page[0]);
+ if (__get_user(c, u))
+ result = -EFAULT;
+
+ status[i] = 0;
+ put_page(page[0]);
+ }
+
+ return result;
+}
+EXPORT_SYMBOL(pnv_npu2_handle_fault);
+
+int pnv_npu2_init(struct pci_controller *hose)
+{
+ unsigned int i;
+ u64 mmio_atsd;
+ static int npu_index;
+ struct npu *npu;
+ int ret;
+
+ npu = kzalloc(sizeof(*npu), GFP_KERNEL);
+ if (!npu)
+ return -ENOMEM;
+
+ npu->nmmu_flush = of_property_read_bool(hose->dn, "ibm,nmmu-flush");
+
+ for (i = 0; i < ARRAY_SIZE(npu->mmio_atsd_regs) &&
+ !of_property_read_u64_index(hose->dn, "ibm,mmio-atsd",
+ i, &mmio_atsd); i++)
+ npu->mmio_atsd_regs[i] = ioremap(mmio_atsd, 32);
+
+ pr_info("NPU%d: Found %d MMIO ATSD registers", hose->global_number, i);
+ npu->mmio_atsd_count = i;
+ npu->mmio_atsd_usage = 0;
+ npu_index++;
+ if (WARN_ON(npu_index >= NV_MAX_NPUS)) {
+ ret = -ENOSPC;
+ goto fail_exit;
+ }
+ max_npu2_index = npu_index;
+ npu->index = npu_index;
+ hose->npu = npu;
+
+ return 0;
+
+fail_exit:
+ for (i = 0; i < npu->mmio_atsd_count; ++i)
+ iounmap(npu->mmio_atsd_regs[i]);
+
+ kfree(npu);
+
+ return ret;
+}
diff --git a/arch/powerpc/sysdev/Kconfig b/arch/powerpc/sysdev/Kconfig
index e0dbec7..e25e1bb 100644
--- a/arch/powerpc/sysdev/Kconfig
+++ b/arch/powerpc/sysdev/Kconfig
@@ -42,3 +42,6 @@ config FSL_CORENET_RCPM
bool
help
This option enables support for RCPM (Run Control/Power Management).
+
+config PPC_NPU
+ def_bool y if (PPC_POWERNV || PPC_PSERIES) && PPC_RADIX_MMU
--
2.17.1
^ permalink raw reply related [flat|nested] 3+ messages in thread