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* [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers
@ 2019-12-18 15:09 Eddie James
  2019-12-18 15:09 ` [PATCH v3 01/12] dt-bindings: interrupt-controller: Add Aspeed SCU interrupt controller Eddie James
                   ` (11 more replies)
  0 siblings, 12 replies; 21+ messages in thread
From: Eddie James @ 2019-12-18 15:09 UTC (permalink / raw)
  To: linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, jason, maz, robh+dt,
	tglx, joel, andrew, eajames

This series first adds a driver to control the interrupt controller provided by
the System Control Unit (SCU) on the AST2500 and AST2600 SOCs. The interrupts
made available are necessary for the control of the XDMA engine embedded in the
same Aspeed SOCs.
This series then adds a driver to control the XDMA engine. This driver was
previously sent to the list without support for the AST2600, and has been
refactored significantly to enable that support. The XDMA engine performs
automatic DMA operations between the Aspeed SOC (acting as a BMC) and a host
processor.

Changes since v2:
 - See individual patches
 - Drop rainier dts patch
 - In summary, remove references to VGA memory as the XDMA driver doesn't care
   where it is. Remove SDRAM controller reference. Move user reset
   functionality to a separate patch and make it an ioctl.

Changes since v1:
 - See individual patches
 - In summary, first the irqchip driver switched to use the parent SCU regmap
   rather than iomapping it's register. Secondly, the XDMA initialization
   switched to use properties from the device tree rather than dynamically
   calculate memory spaces, and system config.

Eddie James (12):
  dt-bindings: interrupt-controller: Add Aspeed SCU interrupt controller
  irqchip: Add Aspeed SCU interrupt controller
  ARM: dts: aspeed: ast2500: Add SCU interrupt controller
  ARM: dts: aspeed: ast2600: Add SCU interrupt controllers
  dt-bindings: soc: Add Aspeed XDMA Engine
  soc: aspeed: Add XDMA Engine Driver
  soc: aspeed: xdma: Add user interface
  soc: aspeed: xdma: Add reset ioctl
  ARM: dts: aspeed: ast2500: Add XDMA Engine
  ARM: dts: aspeed: ast2600: Add XDMA Engine
  ARM: dts: aspeed: witherspoon: Enable XDMA Engine
  ARM: dts: aspeed: tacoma: Enable XDMA engine

 .../aspeed,ast2xxx-scu-ic.txt                 |   23 +
 .../devicetree/bindings/soc/aspeed/xdma.txt   |   40 +
 MAINTAINERS                                   |   16 +
 arch/arm/boot/dts/aspeed-bmc-opp-tacoma.dts   |    5 +
 .../boot/dts/aspeed-bmc-opp-witherspoon.dts   |    5 +
 arch/arm/boot/dts/aspeed-g5.dtsi              |   19 +
 arch/arm/boot/dts/aspeed-g6.dtsi              |   27 +
 drivers/irqchip/Makefile                      |    2 +-
 drivers/irqchip/irq-aspeed-scu-ic.c           |  239 ++++
 drivers/soc/aspeed/Kconfig                    |    8 +
 drivers/soc/aspeed/Makefile                   |    1 +
 drivers/soc/aspeed/aspeed-xdma.c              | 1014 +++++++++++++++++
 .../interrupt-controller/aspeed-scu-ic.h      |   23 +
 include/uapi/linux/aspeed-xdma.h              |   42 +
 14 files changed, 1463 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2xxx-scu-ic.txt
 create mode 100644 Documentation/devicetree/bindings/soc/aspeed/xdma.txt
 create mode 100644 drivers/irqchip/irq-aspeed-scu-ic.c
 create mode 100644 drivers/soc/aspeed/aspeed-xdma.c
 create mode 100644 include/dt-bindings/interrupt-controller/aspeed-scu-ic.h
 create mode 100644 include/uapi/linux/aspeed-xdma.h

-- 
2.24.0


^ permalink raw reply	[flat|nested] 21+ messages in thread

* [PATCH v3 01/12] dt-bindings: interrupt-controller: Add Aspeed SCU interrupt controller
  2019-12-18 15:09 [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
@ 2019-12-18 15:09 ` Eddie James
  2019-12-18 15:09 ` [PATCH v3 02/12] irqchip: " Eddie James
                   ` (10 subsequent siblings)
  11 siblings, 0 replies; 21+ messages in thread
From: Eddie James @ 2019-12-18 15:09 UTC (permalink / raw)
  To: linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, jason, maz, robh+dt,
	tglx, joel, andrew, eajames

Document the Aspeed SCU interrupt controller and add an include file
for the interrupts it provides.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Andrew Jeffery <andrew@aj.id.au>
---
 .../aspeed,ast2xxx-scu-ic.txt                 | 23 +++++++++++++++++++
 MAINTAINERS                                   |  7 ++++++
 .../interrupt-controller/aspeed-scu-ic.h      | 23 +++++++++++++++++++
 3 files changed, 53 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2xxx-scu-ic.txt
 create mode 100644 include/dt-bindings/interrupt-controller/aspeed-scu-ic.h

diff --git a/Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2xxx-scu-ic.txt b/Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2xxx-scu-ic.txt
new file mode 100644
index 000000000000..251ed44171db
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2xxx-scu-ic.txt
@@ -0,0 +1,23 @@
+Aspeed AST25XX and AST26XX SCU Interrupt Controller
+
+Required Properties:
+ - #interrupt-cells		: must be 1
+ - compatible			: must be "aspeed,ast2500-scu-ic",
+				  "aspeed,ast2600-scu-ic0" or
+				  "aspeed,ast2600-scu-ic1"
+ - interrupts			: interrupt from the parent controller
+ - interrupt-controller		: indicates that the controller receives and
+				  fires new interrupts for child busses
+
+Example:
+
+    syscon@1e6e2000 {
+        ranges = <0 0x1e6e2000 0x1a8>;
+
+        scu_ic: interrupt-controller@18 {
+            #interrupt-cells = <1>;
+            compatible = "aspeed,ast2500-scu-ic";
+            interrupts = <21>;
+            interrupt-controller;
+        };
+    };
diff --git a/MAINTAINERS b/MAINTAINERS
index 39a8c6a49b81..219cd69d871b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2692,6 +2692,13 @@ S:	Maintained
 F:	drivers/pinctrl/aspeed/
 F:	Documentation/devicetree/bindings/pinctrl/aspeed,*
 
+ASPEED SCU INTERRUPT CONTROLLER DRIVER
+M:	Eddie James <eajames@linux.ibm.com>
+L:	linux-aspeed@lists.ozlabs.org (moderated for non-subscribers)
+S:	Maintained
+F:	Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2xxx-scu-ic.txt
+F:	include/dt-bindings/interrupt-controller/aspeed-scu-ic.h
+
 ASPEED VIDEO ENGINE DRIVER
 M:	Eddie James <eajames@linux.ibm.com>
 L:	linux-media@vger.kernel.org
diff --git a/include/dt-bindings/interrupt-controller/aspeed-scu-ic.h b/include/dt-bindings/interrupt-controller/aspeed-scu-ic.h
new file mode 100644
index 000000000000..f315d5a7f5ee
--- /dev/null
+++ b/include/dt-bindings/interrupt-controller/aspeed-scu-ic.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#ifndef _DT_BINDINGS_INTERRUPT_CONTROLLER_ASPEED_SCU_IC_H_
+#define _DT_BINDINGS_INTERRUPT_CONTROLLER_ASPEED_SCU_IC_H_
+
+#define ASPEED_SCU_IC_VGA_CURSOR_CHANGE			0
+#define ASPEED_SCU_IC_VGA_SCRATCH_REG_CHANGE		1
+
+#define ASPEED_AST2500_SCU_IC_PCIE_RESET_LO_TO_HI	2
+#define ASPEED_AST2500_SCU_IC_PCIE_RESET_HI_TO_LO	3
+#define ASPEED_AST2500_SCU_IC_LPC_RESET_LO_TO_HI	4
+#define ASPEED_AST2500_SCU_IC_LPC_RESET_HI_TO_LO	5
+#define ASPEED_AST2500_SCU_IC_ISSUE_MSI			6
+
+#define ASPEED_AST2600_SCU_IC0_PCIE_PERST_LO_TO_HI	2
+#define ASPEED_AST2600_SCU_IC0_PCIE_PERST_HI_TO_LO	3
+#define ASPEED_AST2600_SCU_IC0_PCIE_RCRST_LO_TO_HI	4
+#define ASPEED_AST2600_SCU_IC0_PCIE_RCRST_HI_TO_LO	5
+
+#define ASPEED_AST2600_SCU_IC1_LPC_RESET_LO_TO_HI	0
+#define ASPEED_AST2600_SCU_IC1_LPC_RESET_HI_TO_LO	1
+
+#endif /* _DT_BINDINGS_INTERRUPT_CONTROLLER_ASPEED_SCU_IC_H_ */
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v3 02/12] irqchip: Add Aspeed SCU interrupt controller
  2019-12-18 15:09 [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
  2019-12-18 15:09 ` [PATCH v3 01/12] dt-bindings: interrupt-controller: Add Aspeed SCU interrupt controller Eddie James
@ 2019-12-18 15:09 ` Eddie James
  2019-12-18 15:09 ` [PATCH v3 03/12] ARM: dts: aspeed: ast2500: Add " Eddie James
                   ` (9 subsequent siblings)
  11 siblings, 0 replies; 21+ messages in thread
From: Eddie James @ 2019-12-18 15:09 UTC (permalink / raw)
  To: linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, jason, maz, robh+dt,
	tglx, joel, andrew, eajames

The Aspeed SOCs provide some interrupts through the System Control
Unit registers. Add an interrupt controller that provides these
interrupts to the system.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
---
 MAINTAINERS                         |   1 +
 drivers/irqchip/Makefile            |   2 +-
 drivers/irqchip/irq-aspeed-scu-ic.c | 239 ++++++++++++++++++++++++++++
 3 files changed, 241 insertions(+), 1 deletion(-)
 create mode 100644 drivers/irqchip/irq-aspeed-scu-ic.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 219cd69d871b..ac9c120d192b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2697,6 +2697,7 @@ M:	Eddie James <eajames@linux.ibm.com>
 L:	linux-aspeed@lists.ozlabs.org (moderated for non-subscribers)
 S:	Maintained
 F:	Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2xxx-scu-ic.txt
+F:	drivers/irqchip/irq-aspeed-scu-ic.c
 F:	include/dt-bindings/interrupt-controller/aspeed-scu-ic.h
 
 ASPEED VIDEO ENGINE DRIVER
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index e806dda690ea..6c9262c673bf 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -87,7 +87,7 @@ obj-$(CONFIG_MVEBU_SEI)			+= irq-mvebu-sei.o
 obj-$(CONFIG_LS_EXTIRQ)			+= irq-ls-extirq.o
 obj-$(CONFIG_LS_SCFG_MSI)		+= irq-ls-scfg-msi.o
 obj-$(CONFIG_EZNPS_GIC)			+= irq-eznps.o
-obj-$(CONFIG_ARCH_ASPEED)		+= irq-aspeed-vic.o irq-aspeed-i2c-ic.o
+obj-$(CONFIG_ARCH_ASPEED)		+= irq-aspeed-vic.o irq-aspeed-i2c-ic.o irq-aspeed-scu-ic.o
 obj-$(CONFIG_STM32_EXTI) 		+= irq-stm32-exti.o
 obj-$(CONFIG_QCOM_IRQ_COMBINER)		+= qcom-irq-combiner.o
 obj-$(CONFIG_IRQ_UNIPHIER_AIDET)	+= irq-uniphier-aidet.o
diff --git a/drivers/irqchip/irq-aspeed-scu-ic.c b/drivers/irqchip/irq-aspeed-scu-ic.c
new file mode 100644
index 000000000000..c90a3346b985
--- /dev/null
+++ b/drivers/irqchip/irq-aspeed-scu-ic.c
@@ -0,0 +1,239 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Aspeed AST24XX, AST25XX, and AST26XX SCU Interrupt Controller
+ * Copyright 2019 IBM Corporation
+ *
+ * Eddie James <eajames@linux.ibm.com>
+ */
+
+#include <linux/bitops.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_irq.h>
+#include <linux/regmap.h>
+
+#define ASPEED_SCU_IC_REG		0x018
+#define ASPEED_SCU_IC_SHIFT		0
+#define ASPEED_SCU_IC_ENABLE		GENMASK(6, ASPEED_SCU_IC_SHIFT)
+#define ASPEED_SCU_IC_NUM_IRQS		7
+#define ASPEED_SCU_IC_STATUS_SHIFT	16
+
+#define ASPEED_AST2600_SCU_IC0_REG	0x560
+#define ASPEED_AST2600_SCU_IC0_SHIFT	0
+#define ASPEED_AST2600_SCU_IC0_ENABLE	\
+	GENMASK(5, ASPEED_AST2600_SCU_IC0_SHIFT)
+#define ASPEED_AST2600_SCU_IC0_NUM_IRQS	6
+
+#define ASPEED_AST2600_SCU_IC1_REG	0x570
+#define ASPEED_AST2600_SCU_IC1_SHIFT	4
+#define ASPEED_AST2600_SCU_IC1_ENABLE	\
+	GENMASK(5, ASPEED_AST2600_SCU_IC1_SHIFT)
+#define ASPEED_AST2600_SCU_IC1_NUM_IRQS	2
+
+struct aspeed_scu_ic {
+	unsigned long irq_enable;
+	unsigned long irq_shift;
+	unsigned int num_irqs;
+	unsigned int reg;
+	struct regmap *scu;
+	struct irq_domain *irq_domain;
+};
+
+static void aspeed_scu_ic_irq_handler(struct irq_desc *desc)
+{
+	unsigned int irq;
+	unsigned int sts;
+	unsigned long bit;
+	unsigned long enabled;
+	unsigned long max;
+	unsigned long status;
+	struct aspeed_scu_ic *scu_ic = irq_desc_get_handler_data(desc);
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	unsigned int mask = scu_ic->irq_enable << ASPEED_SCU_IC_STATUS_SHIFT;
+
+	chained_irq_enter(chip, desc);
+
+	/*
+	 * The SCU IC has just one register to control its operation and read
+	 * status. The interrupt enable bits occupy the lower 16 bits of the
+	 * register, while the interrupt status bits occupy the upper 16 bits.
+	 * The status bit for a given interrupt is always 16 bits shifted from
+	 * the enable bit for the same interrupt.
+	 * Therefore, perform the IRQ operations in the enable bit space by
+	 * shifting the status down to get the mapping and then back up to
+	 * clear the bit.
+	 */
+	regmap_read(scu_ic->scu, scu_ic->reg, &sts);
+	enabled = sts & scu_ic->irq_enable;
+	status = (sts >> ASPEED_SCU_IC_STATUS_SHIFT) & enabled;
+
+	bit = scu_ic->irq_shift;
+	max = scu_ic->num_irqs + bit;
+
+	for_each_set_bit_from(bit, &status, max) {
+		irq = irq_find_mapping(scu_ic->irq_domain,
+				       bit - scu_ic->irq_shift);
+		generic_handle_irq(irq);
+
+		regmap_update_bits(scu_ic->scu, scu_ic->reg, mask,
+				   BIT(bit + ASPEED_SCU_IC_STATUS_SHIFT));
+	}
+
+	chained_irq_exit(chip, desc);
+}
+
+static void aspeed_scu_ic_irq_mask(struct irq_data *data)
+{
+	struct aspeed_scu_ic *scu_ic = irq_data_get_irq_chip_data(data);
+	unsigned int mask = BIT(data->hwirq + scu_ic->irq_shift) |
+		(scu_ic->irq_enable << ASPEED_SCU_IC_STATUS_SHIFT);
+
+	/*
+	 * Status bits are cleared by writing 1. In order to prevent the mask
+	 * operation from clearing the status bits, they should be under the
+	 * mask and written with 0.
+	 */
+	regmap_update_bits(scu_ic->scu, scu_ic->reg, mask, 0);
+}
+
+static void aspeed_scu_ic_irq_unmask(struct irq_data *data)
+{
+	struct aspeed_scu_ic *scu_ic = irq_data_get_irq_chip_data(data);
+	unsigned int bit = BIT(data->hwirq + scu_ic->irq_shift);
+	unsigned int mask = bit |
+		(scu_ic->irq_enable << ASPEED_SCU_IC_STATUS_SHIFT);
+
+	/*
+	 * Status bits are cleared by writing 1. In order to prevent the unmask
+	 * operation from clearing the status bits, they should be under the
+	 * mask and written with 0.
+	 */
+	regmap_update_bits(scu_ic->scu, scu_ic->reg, mask, bit);
+}
+
+static int aspeed_scu_ic_irq_set_affinity(struct irq_data *data,
+					  const struct cpumask *dest,
+					  bool force)
+{
+	return -EINVAL;
+}
+
+static struct irq_chip aspeed_scu_ic_chip = {
+	.name			= "aspeed-scu-ic",
+	.irq_mask		= aspeed_scu_ic_irq_mask,
+	.irq_unmask		= aspeed_scu_ic_irq_unmask,
+	.irq_set_affinity	= aspeed_scu_ic_irq_set_affinity,
+};
+
+static int aspeed_scu_ic_map(struct irq_domain *domain, unsigned int irq,
+			     irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler(irq, &aspeed_scu_ic_chip, handle_level_irq);
+	irq_set_chip_data(irq, domain->host_data);
+
+	return 0;
+}
+
+static const struct irq_domain_ops aspeed_scu_ic_domain_ops = {
+	.map = aspeed_scu_ic_map,
+};
+
+static int aspeed_scu_ic_of_init_common(struct aspeed_scu_ic *scu_ic,
+					struct device_node *node)
+{
+	int irq;
+	int rc = 0;
+
+	if (!node->parent) {
+		rc = -ENODEV;
+		goto err;
+	}
+
+	scu_ic->scu = syscon_node_to_regmap(node->parent);
+	if (IS_ERR(scu_ic->scu)) {
+		rc = PTR_ERR(scu_ic->scu);
+		goto err;
+	}
+
+	irq = irq_of_parse_and_map(node, 0);
+	if (irq < 0) {
+		rc = irq;
+		goto err;
+	}
+
+	scu_ic->irq_domain = irq_domain_add_linear(node, scu_ic->num_irqs,
+						   &aspeed_scu_ic_domain_ops,
+						   scu_ic);
+	if (!scu_ic->irq_domain) {
+		rc = -ENOMEM;
+		goto err;
+	}
+
+	irq_set_chained_handler_and_data(irq, aspeed_scu_ic_irq_handler,
+					 scu_ic);
+
+	return 0;
+
+err:
+	kfree(scu_ic);
+
+	return rc;
+}
+
+static int __init aspeed_scu_ic_of_init(struct device_node *node,
+					struct device_node *parent)
+{
+	struct aspeed_scu_ic *scu_ic = kzalloc(sizeof(*scu_ic), GFP_KERNEL);
+
+	if (!scu_ic)
+		return -ENOMEM;
+
+	scu_ic->irq_enable = ASPEED_SCU_IC_ENABLE;
+	scu_ic->irq_shift = ASPEED_SCU_IC_SHIFT;
+	scu_ic->num_irqs = ASPEED_SCU_IC_NUM_IRQS;
+	scu_ic->reg = ASPEED_SCU_IC_REG;
+
+	return aspeed_scu_ic_of_init_common(scu_ic, node);
+}
+
+static int __init aspeed_ast2600_scu_ic0_of_init(struct device_node *node,
+						 struct device_node *parent)
+{
+	struct aspeed_scu_ic *scu_ic = kzalloc(sizeof(*scu_ic), GFP_KERNEL);
+
+	if (!scu_ic)
+		return -ENOMEM;
+
+	scu_ic->irq_enable = ASPEED_AST2600_SCU_IC0_ENABLE;
+	scu_ic->irq_shift = ASPEED_AST2600_SCU_IC0_SHIFT;
+	scu_ic->num_irqs = ASPEED_AST2600_SCU_IC0_NUM_IRQS;
+	scu_ic->reg = ASPEED_AST2600_SCU_IC0_REG;
+
+	return aspeed_scu_ic_of_init_common(scu_ic, node);
+}
+
+static int __init aspeed_ast2600_scu_ic1_of_init(struct device_node *node,
+						 struct device_node *parent)
+{
+	struct aspeed_scu_ic *scu_ic = kzalloc(sizeof(*scu_ic), GFP_KERNEL);
+
+	if (!scu_ic)
+		return -ENOMEM;
+
+	scu_ic->irq_enable = ASPEED_AST2600_SCU_IC1_ENABLE;
+	scu_ic->irq_shift = ASPEED_AST2600_SCU_IC1_SHIFT;
+	scu_ic->num_irqs = ASPEED_AST2600_SCU_IC1_NUM_IRQS;
+	scu_ic->reg = ASPEED_AST2600_SCU_IC1_REG;
+
+	return aspeed_scu_ic_of_init_common(scu_ic, node);
+}
+
+IRQCHIP_DECLARE(ast2400_scu_ic, "aspeed,ast2400-scu-ic", aspeed_scu_ic_of_init);
+IRQCHIP_DECLARE(ast2500_scu_ic, "aspeed,ast2500-scu-ic", aspeed_scu_ic_of_init);
+IRQCHIP_DECLARE(ast2600_scu_ic0, "aspeed,ast2600-scu-ic0",
+		aspeed_ast2600_scu_ic0_of_init);
+IRQCHIP_DECLARE(ast2600_scu_ic1, "aspeed,ast2600-scu-ic1",
+		aspeed_ast2600_scu_ic1_of_init);
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v3 03/12] ARM: dts: aspeed: ast2500: Add SCU interrupt controller
  2019-12-18 15:09 [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
  2019-12-18 15:09 ` [PATCH v3 01/12] dt-bindings: interrupt-controller: Add Aspeed SCU interrupt controller Eddie James
  2019-12-18 15:09 ` [PATCH v3 02/12] irqchip: " Eddie James
@ 2019-12-18 15:09 ` Eddie James
  2019-12-18 22:34   ` Andrew Jeffery
  2019-12-18 15:09 ` [PATCH v3 04/12] ARM: dts: aspeed: ast2600: Add SCU interrupt controllers Eddie James
                   ` (8 subsequent siblings)
  11 siblings, 1 reply; 21+ messages in thread
From: Eddie James @ 2019-12-18 15:09 UTC (permalink / raw)
  To: linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, jason, maz, robh+dt,
	tglx, joel, andrew, eajames

Add a node for the interrupt controller provided by the SCU.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
Changes since v2:
 - Remove the addition of ranges in the SCU

 arch/arm/boot/dts/aspeed-g5.dtsi | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/arm/boot/dts/aspeed-g5.dtsi b/arch/arm/boot/dts/aspeed-g5.dtsi
index a259c63fff06..4791a50e37ee 100644
--- a/arch/arm/boot/dts/aspeed-g5.dtsi
+++ b/arch/arm/boot/dts/aspeed-g5.dtsi
@@ -231,6 +231,13 @@ p2a: p2a-control {
 					compatible = "aspeed,ast2500-p2a-ctrl";
 					status = "disabled";
 				};
+
+				scu_ic: interrupt-controller@18 {
+					#interrupt-cells = <1>;
+					compatible = "aspeed,ast2500-scu-ic";
+					interrupts = <21>;
+					interrupt-controller;
+				};
 			};
 
 			rng: hwrng@1e6e2078 {
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v3 04/12] ARM: dts: aspeed: ast2600: Add SCU interrupt controllers
  2019-12-18 15:09 [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
                   ` (2 preceding siblings ...)
  2019-12-18 15:09 ` [PATCH v3 03/12] ARM: dts: aspeed: ast2500: Add " Eddie James
@ 2019-12-18 15:09 ` Eddie James
  2019-12-18 15:09 ` [PATCH v3 05/12] dt-bindings: soc: Add Aspeed XDMA Engine Eddie James
                   ` (7 subsequent siblings)
  11 siblings, 0 replies; 21+ messages in thread
From: Eddie James @ 2019-12-18 15:09 UTC (permalink / raw)
  To: linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, jason, maz, robh+dt,
	tglx, joel, andrew, eajames

Add nodes for the interrupt controllers provided by the SCU.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
---
 arch/arm/boot/dts/aspeed-g6.dtsi | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/arch/arm/boot/dts/aspeed-g6.dtsi b/arch/arm/boot/dts/aspeed-g6.dtsi
index 5f6142d99eeb..ead336e93a12 100644
--- a/arch/arm/boot/dts/aspeed-g6.dtsi
+++ b/arch/arm/boot/dts/aspeed-g6.dtsi
@@ -288,6 +288,20 @@ smp-memram@180 {
 					compatible = "aspeed,ast2600-smpmem";
 					reg = <0x180 0x40>;
 				};
+
+				scu_ic0: interrupt-controller@0 {
+					#interrupt-cells = <1>;
+					compatible = "aspeed,ast2600-scu-ic0";
+					interrupts = <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>;
+					interrupt-controller;
+				};
+
+				scu_ic1: interrupt-controller@1 {
+					#interrupt-cells = <1>;
+					compatible = "aspeed,ast2600-scu-ic1";
+					interrupts = <GIC_SPI 41 IRQ_TYPE_LEVEL_HIGH>;
+					interrupt-controller;
+				};
 			};
 
 			rng: hwrng@1e6e2524 {
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v3 05/12] dt-bindings: soc: Add Aspeed XDMA Engine
  2019-12-18 15:09 [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
                   ` (3 preceding siblings ...)
  2019-12-18 15:09 ` [PATCH v3 04/12] ARM: dts: aspeed: ast2600: Add SCU interrupt controllers Eddie James
@ 2019-12-18 15:09 ` Eddie James
  2019-12-18 23:12   ` Andrew Jeffery
  2019-12-18 15:09 ` [PATCH v3 06/12] soc: aspeed: Add XDMA Engine Driver Eddie James
                   ` (6 subsequent siblings)
  11 siblings, 1 reply; 21+ messages in thread
From: Eddie James @ 2019-12-18 15:09 UTC (permalink / raw)
  To: linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, jason, maz, robh+dt,
	tglx, joel, andrew, eajames

Document the bindings for the Aspeed AST25XX and AST26XX XDMA engine.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
Changes since v2:
 - Remove 'sdmc', rename 'vga-mem' to 'memory'

 .../devicetree/bindings/soc/aspeed/xdma.txt   | 40 +++++++++++++++++++
 MAINTAINERS                                   |  6 +++
 2 files changed, 46 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/soc/aspeed/xdma.txt

diff --git a/Documentation/devicetree/bindings/soc/aspeed/xdma.txt b/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
new file mode 100644
index 000000000000..58253ea1587b
--- /dev/null
+++ b/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
@@ -0,0 +1,40 @@
+Aspeed AST25XX and AST26XX XDMA Engine
+
+The XDMA Engine embedded in the AST2500 and AST2600 SOCs can perform automatic
+DMA operations over PCI between the SOC (acting as a BMC) and a host processor.
+
+Required properties:
+ - compatible		: must be "aspeed,ast2500-xdma" or
+			  "aspeed,ast2600-xdma"
+ - reg			: contains the address and size of the memory region
+			  associated with the XDMA engine registers
+ - clocks		: clock specifier for the clock associated with the
+			  XDMA engine
+ - resets		: reset specifier for the syscon reset associated with
+			  the XDMA engine
+ - interrupts-extended	: two interrupt cells; the first specifies the global
+			  interrupt for the XDMA engine and the second
+			  specifies the PCI-E reset or PERST interrupt.
+ - scu			: a phandle to the syscon node for the system control
+			  unit of the SOC
+ - memory		: contains the address and size of the memory area to
+			  be used by the XDMA engine for DMA operations
+
+Optional properties:
+ - pcie-device		: should be either "bmc" or "vga", corresponding to
+			  which device should be used by the XDMA engine for
+			  DMA operations. If this property is not set, the XDMA
+			  engine will use the BMC PCI-E device.
+
+Example:
+
+    xdma@1e6e7000 {
+        compatible = "aspeed,ast2500-xdma";
+        reg = <0x1e6e7000 0x100>;
+        clocks = <&syscon ASPEED_CLK_GATE_BCLK>;
+        resets = <&syscon ASPEED_RESET_XDMA>;
+        interrupts-extended = <&vic 6>, <&scu_ic ASPEED_AST2500_SCU_IC_PCIE_RESET_LO_TO_HI>;
+        scu = <&syscon>;
+        pcie-device = "bmc";
+        memory = <0x9f000000 0x01000000>;
+    };
diff --git a/MAINTAINERS b/MAINTAINERS
index ac9c120d192b..8a14d4268bdc 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2708,6 +2708,12 @@ S:	Maintained
 F:	drivers/media/platform/aspeed-video.c
 F:	Documentation/devicetree/bindings/media/aspeed-video.txt
 
+ASPEED XDMA ENGINE DRIVER
+M:	Eddie James <eajames@linux.ibm.com>
+L:	linux-aspeed@lists.ozlabs.org (moderated for non-subscribers)
+S:	Maintained
+F:	Documentation/devicetree/bindings/soc/aspeed/xdma.txt
+
 ASUS NOTEBOOKS AND EEEPC ACPI/WMI EXTRAS DRIVERS
 M:	Corentin Chary <corentin.chary@gmail.com>
 L:	acpi4asus-user@lists.sourceforge.net
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v3 06/12] soc: aspeed: Add XDMA Engine Driver
  2019-12-18 15:09 [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
                   ` (4 preceding siblings ...)
  2019-12-18 15:09 ` [PATCH v3 05/12] dt-bindings: soc: Add Aspeed XDMA Engine Eddie James
@ 2019-12-18 15:09 ` Eddie James
  2019-12-18 23:12   ` Andrew Jeffery
  2019-12-18 15:09 ` [PATCH v3 07/12] soc: aspeed: xdma: Add user interface Eddie James
                   ` (5 subsequent siblings)
  11 siblings, 1 reply; 21+ messages in thread
From: Eddie James @ 2019-12-18 15:09 UTC (permalink / raw)
  To: linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, jason, maz, robh+dt,
	tglx, joel, andrew, eajames

The XDMA engine embedded in the AST2500 and AST2600 SOCs performs PCI
DMA operations between the SOC (acting as a BMC) and a host processor
in a server.

This commit adds a driver to control the XDMA engine and adds functions
to initialize the hardware and memory and start DMA operations.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
Changes since v2:
 - Remove SDRAM memory controller configuration
 - Add client_lock to protect client state
 - Rename things away from "vga"
 - Refactor set_cmd and aspeed_xdma_start a bit
 - Did various suggested cleanup items

 MAINTAINERS                      |   2 +
 drivers/soc/aspeed/Kconfig       |   8 +
 drivers/soc/aspeed/Makefile      |   1 +
 drivers/soc/aspeed/aspeed-xdma.c | 777 +++++++++++++++++++++++++++++++
 include/uapi/linux/aspeed-xdma.h |  38 ++
 5 files changed, 826 insertions(+)
 create mode 100644 drivers/soc/aspeed/aspeed-xdma.c
 create mode 100644 include/uapi/linux/aspeed-xdma.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 8a14d4268bdc..b72cc581c7a3 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2713,6 +2713,8 @@ M:	Eddie James <eajames@linux.ibm.com>
 L:	linux-aspeed@lists.ozlabs.org (moderated for non-subscribers)
 S:	Maintained
 F:	Documentation/devicetree/bindings/soc/aspeed/xdma.txt
+F:	drivers/soc/aspeed/aspeed-xdma.c
+F:	include/uapi/linux/aspeed-xdma.h
 
 ASUS NOTEBOOKS AND EEEPC ACPI/WMI EXTRAS DRIVERS
 M:	Corentin Chary <corentin.chary@gmail.com>
diff --git a/drivers/soc/aspeed/Kconfig b/drivers/soc/aspeed/Kconfig
index 323e177aa74d..2a6c16f9e50b 100644
--- a/drivers/soc/aspeed/Kconfig
+++ b/drivers/soc/aspeed/Kconfig
@@ -29,4 +29,12 @@ config ASPEED_P2A_CTRL
 	  ioctl()s, the driver also provides an interface for userspace mappings to
 	  a pre-defined region.
 
+config ASPEED_XDMA
+	tristate "Aspeed XDMA Engine Driver"
+	depends on SOC_ASPEED && REGMAP && MFD_SYSCON && HAS_DMA
+	help
+	  Enable support for the Aspeed XDMA Engine found on the Aspeed AST2XXX
+	  SOCs. The XDMA engine can perform automatic PCI DMA operations
+	  between the AST2XXX (acting as a BMC) and a host processor.
+
 endmenu
diff --git a/drivers/soc/aspeed/Makefile b/drivers/soc/aspeed/Makefile
index b64be47f2b1f..977b046dfb73 100644
--- a/drivers/soc/aspeed/Makefile
+++ b/drivers/soc/aspeed/Makefile
@@ -2,3 +2,4 @@
 obj-$(CONFIG_ASPEED_LPC_CTRL)	+= aspeed-lpc-ctrl.o
 obj-$(CONFIG_ASPEED_LPC_SNOOP)	+= aspeed-lpc-snoop.o
 obj-$(CONFIG_ASPEED_P2A_CTRL)	+= aspeed-p2a-ctrl.o
+obj-$(CONFIG_ASPEED_XDMA)	+= aspeed-xdma.o
diff --git a/drivers/soc/aspeed/aspeed-xdma.c b/drivers/soc/aspeed/aspeed-xdma.c
new file mode 100644
index 000000000000..cb94adf798b1
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-xdma.c
@@ -0,0 +1,777 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// Copyright IBM Corp 2019
+
+#include <linux/aspeed-xdma.h>
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/fs.h>
+#include <linux/genalloc.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/jiffies.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/poll.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+
+#define DEVICE_NAME				"aspeed-xdma"
+
+#define SCU_AST2500_PCIE_CONF			0x180
+#define SCU_AST2600_PCIE_CONF			0xc20
+#define  SCU_PCIE_CONF_VGA_EN			 BIT(0)
+#define  SCU_PCIE_CONF_VGA_EN_MMIO		 BIT(1)
+#define  SCU_PCIE_CONF_VGA_EN_LPC		 BIT(2)
+#define  SCU_PCIE_CONF_VGA_EN_MSI		 BIT(3)
+#define  SCU_PCIE_CONF_VGA_EN_MCTP		 BIT(4)
+#define  SCU_PCIE_CONF_VGA_EN_IRQ		 BIT(5)
+#define  SCU_PCIE_CONF_VGA_EN_DMA		 BIT(6)
+#define  SCU_PCIE_CONF_BMC_EN			 BIT(8)
+#define  SCU_PCIE_CONF_BMC_EN_MMIO		 BIT(9)
+#define  SCU_PCIE_CONF_BMC_EN_MSI		 BIT(11)
+#define  SCU_PCIE_CONF_BMC_EN_MCTP		 BIT(12)
+#define  SCU_PCIE_CONF_BMC_EN_IRQ		 BIT(13)
+#define  SCU_PCIE_CONF_BMC_EN_DMA		 BIT(14)
+
+#define SCU_AST2500_BMC_CLASS_REV		0x19c
+#define SCU_AST2600_BMC_CLASS_REV		0xc4c
+#define  SCU_BMC_CLASS_REV_XDMA			 0xff000001
+
+#define XDMA_CMDQ_SIZE				PAGE_SIZE
+#define XDMA_NUM_CMDS				\
+	(XDMA_CMDQ_SIZE / sizeof(struct aspeed_xdma_cmd))
+
+/* Aspeed specification requires 10ms after switching the reset line */
+#define XDMA_RESET_TIME_MS			10
+
+#define XDMA_CMD_AST2500_PITCH_SHIFT		3
+#define XDMA_CMD_AST2500_PITCH_BMC		GENMASK_ULL(62, 51)
+#define XDMA_CMD_AST2500_PITCH_HOST		GENMASK_ULL(46, 35)
+#define XDMA_CMD_AST2500_PITCH_UPSTREAM		BIT_ULL(31)
+#define XDMA_CMD_AST2500_PITCH_ADDR		GENMASK_ULL(29, 4)
+#define XDMA_CMD_AST2500_PITCH_ID		BIT_ULL(0)
+#define XDMA_CMD_AST2500_CMD_IRQ_EN		BIT_ULL(31)
+#define XDMA_CMD_AST2500_CMD_LINE_NO		GENMASK_ULL(27, 16)
+#define XDMA_CMD_AST2500_CMD_IRQ_BMC		BIT_ULL(15)
+#define XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT	4
+#define XDMA_CMD_AST2500_CMD_LINE_SIZE		\
+	GENMASK_ULL(14, XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT)
+#define XDMA_CMD_AST2500_CMD_ID			BIT_ULL(1)
+
+#define XDMA_CMD_AST2600_PITCH_BMC		GENMASK_ULL(62, 48)
+#define XDMA_CMD_AST2600_PITCH_HOST		GENMASK_ULL(46, 32)
+#define XDMA_CMD_AST2600_PITCH_ADDR		GENMASK_ULL(30, 0)
+#define XDMA_CMD_AST2600_CMD_64_EN		BIT_ULL(40)
+#define XDMA_CMD_AST2600_CMD_IRQ_BMC		BIT_ULL(37)
+#define XDMA_CMD_AST2600_CMD_IRQ_HOST		BIT_ULL(36)
+#define XDMA_CMD_AST2600_CMD_UPSTREAM		BIT_ULL(32)
+#define XDMA_CMD_AST2600_CMD_LINE_NO		GENMASK_ULL(27, 16)
+#define XDMA_CMD_AST2600_CMD_LINE_SIZE		GENMASK_ULL(14, 0)
+#define XDMA_CMD_AST2600_CMD_MULTILINE_SIZE	GENMASK_ULL(14, 12)
+
+#define XDMA_AST2500_QUEUE_ENTRY_SIZE		4
+#define XDMA_AST2500_HOST_CMDQ_ADDR0		0x00
+#define XDMA_AST2500_HOST_CMDQ_ENDP		0x04
+#define XDMA_AST2500_HOST_CMDQ_WRITEP		0x08
+#define XDMA_AST2500_HOST_CMDQ_READP		0x0c
+#define XDMA_AST2500_BMC_CMDQ_ADDR		0x10
+#define XDMA_AST2500_BMC_CMDQ_ENDP		0x14
+#define XDMA_AST2500_BMC_CMDQ_WRITEP		0x18
+#define XDMA_AST2500_BMC_CMDQ_READP		0x1c
+#define  XDMA_BMC_CMDQ_READP_RESET		 0xee882266
+#define XDMA_AST2500_CTRL			0x20
+#define  XDMA_AST2500_CTRL_US_COMP		 BIT(4)
+#define  XDMA_AST2500_CTRL_DS_COMP		 BIT(5)
+#define  XDMA_AST2500_CTRL_DS_DIRTY		 BIT(6)
+#define  XDMA_AST2500_CTRL_DS_SIZE_256		 BIT(17)
+#define  XDMA_AST2500_CTRL_DS_TIMEOUT		 BIT(28)
+#define  XDMA_AST2500_CTRL_DS_CHECK_ID		 BIT(29)
+#define XDMA_AST2500_STATUS			0x24
+#define  XDMA_AST2500_STATUS_US_COMP		 BIT(4)
+#define  XDMA_AST2500_STATUS_DS_COMP		 BIT(5)
+#define  XDMA_AST2500_STATUS_DS_DIRTY		 BIT(6)
+#define XDMA_AST2500_INPRG_DS_CMD1		0x38
+#define XDMA_AST2500_INPRG_DS_CMD2		0x3c
+#define XDMA_AST2500_INPRG_US_CMD00		0x40
+#define XDMA_AST2500_INPRG_US_CMD01		0x44
+#define XDMA_AST2500_INPRG_US_CMD10		0x48
+#define XDMA_AST2500_INPRG_US_CMD11		0x4c
+#define XDMA_AST2500_INPRG_US_CMD20		0x50
+#define XDMA_AST2500_INPRG_US_CMD21		0x54
+#define XDMA_AST2500_HOST_CMDQ_ADDR1		0x60
+#define XDMA_AST2500_VGA_CMDQ_ADDR0		0x64
+#define XDMA_AST2500_VGA_CMDQ_ENDP		0x68
+#define XDMA_AST2500_VGA_CMDQ_WRITEP		0x6c
+#define XDMA_AST2500_VGA_CMDQ_READP		0x70
+#define XDMA_AST2500_VGA_CMD_STATUS		0x74
+#define XDMA_AST2500_VGA_CMDQ_ADDR1		0x78
+
+#define XDMA_AST2600_QUEUE_ENTRY_SIZE		2
+#define XDMA_AST2600_HOST_CMDQ_ADDR0		0x00
+#define XDMA_AST2600_HOST_CMDQ_ADDR1		0x04
+#define XDMA_AST2600_HOST_CMDQ_ENDP		0x08
+#define XDMA_AST2600_HOST_CMDQ_WRITEP		0x0c
+#define XDMA_AST2600_HOST_CMDQ_READP		0x10
+#define XDMA_AST2600_BMC_CMDQ_ADDR		0x14
+#define XDMA_AST2600_BMC_CMDQ_ENDP		0x18
+#define XDMA_AST2600_BMC_CMDQ_WRITEP		0x1c
+#define XDMA_AST2600_BMC_CMDQ_READP		0x20
+#define XDMA_AST2600_VGA_CMDQ_ADDR0		0x24
+#define XDMA_AST2600_VGA_CMDQ_ADDR1		0x28
+#define XDMA_AST2600_VGA_CMDQ_ENDP		0x2c
+#define XDMA_AST2600_VGA_CMDQ_WRITEP		0x30
+#define XDMA_AST2600_VGA_CMDQ_READP		0x34
+#define XDMA_AST2600_CTRL			0x38
+#define  XDMA_AST2600_CTRL_US_COMP		 BIT(16)
+#define  XDMA_AST2600_CTRL_DS_COMP		 BIT(17)
+#define  XDMA_AST2600_CTRL_DS_DIRTY		 BIT(18)
+#define  XDMA_AST2600_CTRL_DS_SIZE_256		 BIT(20)
+#define XDMA_AST2600_STATUS			0x3c
+#define  XDMA_AST2600_STATUS_US_COMP		 BIT(16)
+#define  XDMA_AST2600_STATUS_DS_COMP		 BIT(17)
+#define  XDMA_AST2600_STATUS_DS_DIRTY		 BIT(18)
+#define XDMA_AST2600_INPRG_DS_CMD00		0x40
+#define XDMA_AST2600_INPRG_DS_CMD01		0x44
+#define XDMA_AST2600_INPRG_DS_CMD10		0x48
+#define XDMA_AST2600_INPRG_DS_CMD11		0x4c
+#define XDMA_AST2600_INPRG_DS_CMD20		0x50
+#define XDMA_AST2600_INPRG_DS_CMD21		0x54
+#define XDMA_AST2600_INPRG_US_CMD00		0x60
+#define XDMA_AST2600_INPRG_US_CMD01		0x64
+#define XDMA_AST2600_INPRG_US_CMD10		0x68
+#define XDMA_AST2600_INPRG_US_CMD11		0x6c
+#define XDMA_AST2600_INPRG_US_CMD20		0x70
+#define XDMA_AST2600_INPRG_US_CMD21		0x74
+
+struct aspeed_xdma_cmd {
+	u64 host_addr;
+	u64 pitch;
+	u64 cmd;
+	u64 reserved;
+};
+
+struct aspeed_xdma_regs {
+	u8 bmc_cmdq_addr;
+	u8 bmc_cmdq_endp;
+	u8 bmc_cmdq_writep;
+	u8 bmc_cmdq_readp;
+	u8 control;
+	u8 status;
+};
+
+struct aspeed_xdma_status_bits {
+	u32 us_comp;
+	u32 ds_comp;
+	u32 ds_dirty;
+};
+
+struct aspeed_xdma;
+
+struct aspeed_xdma_chip {
+	u32 control;
+	u32 scu_bmc_class;
+	u32 scu_pcie_conf;
+	unsigned int queue_entry_size;
+	struct aspeed_xdma_regs regs;
+	struct aspeed_xdma_status_bits status_bits;
+	unsigned int (*set_cmd)(struct aspeed_xdma *ctx,
+				struct aspeed_xdma_cmd *cmds,
+				struct aspeed_xdma_op *op, u32 bmc_addr);
+};
+
+struct aspeed_xdma_client;
+
+struct aspeed_xdma {
+	const struct aspeed_xdma_chip *chip;
+
+	struct device *dev;
+	void __iomem *base;
+	struct clk *clock;
+	struct reset_control *reset;
+
+	/* client_lock protects error and in_progress of the client */
+	spinlock_t client_lock;
+	struct aspeed_xdma_client *current_client;
+
+	/* start_lock protects cmd_idx, cmdq, and the state of the engine */
+	struct mutex start_lock;
+	struct aspeed_xdma_cmd *cmdq;
+	bool upstream;
+	unsigned int cmd_idx;
+
+	/* reset_lock protects in_reset and the reset state of the engine */
+	spinlock_t reset_lock;
+	bool in_reset;
+
+	wait_queue_head_t wait;
+	struct work_struct reset_work;
+
+	u32 mem_phys;
+	u32 mem_size;
+	void __iomem *mem_virt;
+	dma_addr_t cmdq_phys;
+	struct gen_pool *pool;
+};
+
+struct aspeed_xdma_client {
+	struct aspeed_xdma *ctx;
+
+	bool error;
+	bool in_progress;
+	void *virt;
+	dma_addr_t phys;
+	u32 size;
+};
+
+static u32 aspeed_xdma_readl(struct aspeed_xdma *ctx, u8 reg)
+{
+	u32 v = readl(ctx->base + reg);
+
+	dev_dbg(ctx->dev, "read %02x[%08x]\n", reg, v);
+	return v;
+}
+
+static void aspeed_xdma_writel(struct aspeed_xdma *ctx, u8 reg, u32 val)
+{
+	writel(val, ctx->base + reg);
+	dev_dbg(ctx->dev, "write %02x[%08x]\n", reg, val);
+}
+
+static void aspeed_xdma_init_eng(struct aspeed_xdma *ctx)
+{
+	aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_endp,
+			   ctx->chip->queue_entry_size * XDMA_NUM_CMDS);
+	aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_readp,
+			   XDMA_BMC_CMDQ_READP_RESET);
+	aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_writep, 0);
+	aspeed_xdma_writel(ctx, ctx->chip->regs.control, ctx->chip->control);
+	aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_addr, ctx->cmdq_phys);
+
+	ctx->cmd_idx = 0;
+	ctx->current_client = NULL;
+}
+
+static unsigned int aspeed_xdma_ast2500_set_cmd(struct aspeed_xdma *ctx,
+						struct aspeed_xdma_cmd *cmds,
+						struct aspeed_xdma_op *op,
+						u32 bmc_addr)
+{
+	unsigned int rc = 1;
+	unsigned int pitch = 1;
+	unsigned int line_no = 1;
+	unsigned int line_size = op->len >>
+		XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT;
+	u64 cmd = XDMA_CMD_AST2500_CMD_IRQ_EN | XDMA_CMD_AST2500_CMD_IRQ_BMC |
+		XDMA_CMD_AST2500_CMD_ID;
+	u64 cmd_pitch = (op->direction ? XDMA_CMD_AST2500_PITCH_UPSTREAM : 0) |
+		XDMA_CMD_AST2500_PITCH_ID;
+
+	dev_dbg(ctx->dev, "xdma %s ast2500: bmc[%08x] len[%08x] host[%08x]\n",
+		op->direction ? "upstream" : "downstream", bmc_addr, op->len,
+		(u32)op->host_addr);
+
+	if (op->len > XDMA_CMD_AST2500_CMD_LINE_SIZE) {
+		unsigned int rem;
+		unsigned int total;
+
+		line_no = op->len / XDMA_CMD_AST2500_CMD_LINE_SIZE;
+		total = XDMA_CMD_AST2500_CMD_LINE_SIZE * line_no;
+		rem = (op->len - total) >>
+			XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT;
+		line_size = XDMA_CMD_AST2500_CMD_LINE_SIZE;
+		pitch = line_size >> XDMA_CMD_AST2500_PITCH_SHIFT;
+		line_size >>= XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT;
+
+		if (rem) {
+			u32 rbmc = bmc_addr + total;
+
+			cmds[1].host_addr = op->host_addr + (u64)total;
+			cmds[1].pitch = cmd_pitch |
+				((u64)rbmc & XDMA_CMD_AST2500_PITCH_ADDR) |
+				FIELD_PREP(XDMA_CMD_AST2500_PITCH_HOST, 1) |
+				FIELD_PREP(XDMA_CMD_AST2500_PITCH_BMC, 1);
+			cmds[1].cmd = cmd |
+				FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_NO, 1) |
+				FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_SIZE,
+					   rem);
+			cmds[1].reserved = 0ULL;
+
+			print_hex_dump_debug("xdma rem ", DUMP_PREFIX_OFFSET,
+					     16, 1, &cmds[1], sizeof(*cmds),
+					     true);
+
+			cmd &= ~(XDMA_CMD_AST2500_CMD_IRQ_EN |
+				 XDMA_CMD_AST2500_CMD_IRQ_BMC);
+
+			rc++;
+		}
+	}
+
+	cmds[0].host_addr = op->host_addr;
+	cmds[0].pitch = cmd_pitch |
+		((u64)bmc_addr & XDMA_CMD_AST2500_PITCH_ADDR) |
+		FIELD_PREP(XDMA_CMD_AST2500_PITCH_HOST, pitch) |
+		FIELD_PREP(XDMA_CMD_AST2500_PITCH_BMC, pitch);
+	cmds[0].cmd = cmd | FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_NO, line_no) |
+		FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_SIZE, line_size);
+	cmds[0].reserved = 0ULL;
+
+	print_hex_dump_debug("xdma cmd ", DUMP_PREFIX_OFFSET, 16, 1, cmds,
+			     sizeof(*cmds), true);
+
+	return rc;
+}
+
+static unsigned int aspeed_xdma_ast2600_set_cmd(struct aspeed_xdma *ctx,
+						struct aspeed_xdma_cmd *cmds,
+						struct aspeed_xdma_op *op,
+						u32 bmc_addr)
+{
+	unsigned int rc = 1;
+	unsigned int pitch = 1;
+	unsigned int line_no = 1;
+	unsigned int line_size = op->len;
+	u64 cmd = XDMA_CMD_AST2600_CMD_IRQ_BMC |
+		(op->direction ? XDMA_CMD_AST2600_CMD_UPSTREAM : 0);
+
+	if (op->host_addr & 0xffffffff00000000ULL ||
+	    (op->host_addr + (u64)op->len) & 0xffffffff00000000ULL)
+		cmd |= XDMA_CMD_AST2600_CMD_64_EN;
+
+	dev_dbg(ctx->dev, "xdma %s ast2600: bmc[%08x] len[%08x] "
+		"host[%016llx]\n", op->direction ? "upstream" : "downstream",
+		bmc_addr, op->len, op->host_addr);
+
+	if (op->len > XDMA_CMD_AST2600_CMD_LINE_SIZE) {
+		unsigned int rem;
+		unsigned int total;
+
+		line_no = op->len / XDMA_CMD_AST2600_CMD_MULTILINE_SIZE;
+		total = XDMA_CMD_AST2600_CMD_MULTILINE_SIZE * line_no;
+		rem = op->len - total;
+		line_size = XDMA_CMD_AST2600_CMD_MULTILINE_SIZE;
+		pitch = line_size;
+
+		if (rem) {
+			u32 rbmc = bmc_addr + total;
+
+			cmds[1].host_addr = op->host_addr + (u64)total;
+			cmds[1].pitch =
+				((u64)rbmc & XDMA_CMD_AST2600_PITCH_ADDR) |
+				FIELD_PREP(XDMA_CMD_AST2600_PITCH_HOST, 1) |
+				FIELD_PREP(XDMA_CMD_AST2600_PITCH_BMC, 1);
+			cmds[1].cmd = cmd |
+				FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_NO, 1) |
+				FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_SIZE,
+					   rem);
+			cmds[1].reserved = 0ULL;
+
+			print_hex_dump_debug("xdma rem ", DUMP_PREFIX_OFFSET,
+					     16, 1, &cmds[1], sizeof(*cmds),
+					     true);
+
+			cmd &= ~XDMA_CMD_AST2600_CMD_IRQ_BMC;
+
+			rc++;
+		}
+	}
+
+	cmds[0].host_addr = op->host_addr;
+	cmds[0].pitch = ((u64)bmc_addr & XDMA_CMD_AST2600_PITCH_ADDR) |
+		FIELD_PREP(XDMA_CMD_AST2600_PITCH_HOST, pitch) |
+		FIELD_PREP(XDMA_CMD_AST2600_PITCH_BMC, pitch);
+	cmds[0].cmd = cmd | FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_NO, line_no) |
+		FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_SIZE, line_size);
+	cmds[0].reserved = 0ULL;
+
+	print_hex_dump_debug("xdma cmd ", DUMP_PREFIX_OFFSET, 16, 1, cmds,
+			     sizeof(*cmds), true);
+
+	return rc;
+}
+
+static void aspeed_xdma_start(struct aspeed_xdma *ctx,
+			      struct aspeed_xdma_op *op, u32 bmc_addr,
+			      struct aspeed_xdma_client *client)
+{
+	unsigned long flags;
+	struct aspeed_xdma_cmd cmds[2];
+	unsigned int rc = ctx->chip->set_cmd(ctx, cmds, op, bmc_addr);
+
+	mutex_lock(&ctx->start_lock);
+
+	memcpy(&ctx->cmdq[ctx->cmd_idx], cmds,
+	       rc * sizeof(struct aspeed_xdma_cmd));
+	ctx->cmd_idx = (ctx->cmd_idx + rc) % XDMA_NUM_CMDS;
+	ctx->upstream = !!op->direction;
+
+	spin_lock_irqsave(&ctx->client_lock, flags);
+
+	client->error = false;
+	client->in_progress = true;
+	ctx->current_client = client;
+
+	spin_unlock_irqrestore(&ctx->client_lock, flags);
+
+	aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_writep,
+			   ctx->cmd_idx * ctx->chip->queue_entry_size);
+
+	mutex_unlock(&ctx->start_lock);
+}
+
+static void aspeed_xdma_done(struct aspeed_xdma *ctx, bool error)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&ctx->client_lock, flags);
+
+	if (ctx->current_client) {
+		ctx->current_client->error = error;
+		ctx->current_client->in_progress = false;
+		ctx->current_client = NULL;
+	}
+
+	spin_unlock_irqrestore(&ctx->client_lock, flags);
+
+	wake_up_interruptible_all(&ctx->wait);
+}
+
+static irqreturn_t aspeed_xdma_irq(int irq, void *arg)
+{
+	struct aspeed_xdma *ctx = arg;
+	u32 status = aspeed_xdma_readl(ctx, ctx->chip->regs.status);
+
+	if (status & ctx->chip->status_bits.ds_dirty) {
+		aspeed_xdma_done(ctx, true);
+	} else {
+		if (status & ctx->chip->status_bits.us_comp) {
+			if (ctx->upstream)
+				aspeed_xdma_done(ctx, false);
+		}
+
+		if (status & ctx->chip->status_bits.ds_comp) {
+			if (!ctx->upstream)
+				aspeed_xdma_done(ctx, false);
+		}
+	}
+
+	aspeed_xdma_writel(ctx, ctx->chip->regs.status, status);
+
+	return IRQ_HANDLED;
+}
+
+static void aspeed_xdma_reset(struct aspeed_xdma *ctx)
+{
+	reset_control_assert(ctx->reset);
+	msleep(XDMA_RESET_TIME_MS);
+
+	reset_control_deassert(ctx->reset);
+	msleep(XDMA_RESET_TIME_MS);
+
+	aspeed_xdma_init_eng(ctx);
+
+	ctx->in_reset = false;
+	aspeed_xdma_done(ctx, true);
+}
+
+static void aspeed_xdma_reset_work(struct work_struct *work)
+{
+	struct aspeed_xdma *ctx = container_of(work, struct aspeed_xdma,
+					       reset_work);
+
+	/*
+	 * Lock to make sure operations aren't started while the engine is
+	 * in reset.
+	 */
+	mutex_lock(&ctx->start_lock);
+
+	aspeed_xdma_reset(ctx);
+
+	mutex_unlock(&ctx->start_lock);
+}
+
+static irqreturn_t aspeed_xdma_pcie_irq(int irq, void *arg)
+{
+	unsigned long flags;
+	struct aspeed_xdma *ctx = arg;
+
+	dev_dbg(ctx->dev, "pcie reset\n");
+
+	spin_lock_irqsave(&ctx->reset_lock, flags);
+	if (ctx->in_reset) {
+		spin_unlock_irqrestore(&ctx->reset_lock, flags);
+		return IRQ_HANDLED;
+	}
+
+	ctx->in_reset = true;
+	spin_unlock_irqrestore(&ctx->reset_lock, flags);
+
+	schedule_work(&ctx->reset_work);
+	return IRQ_HANDLED;
+}
+
+static int aspeed_xdma_probe(struct platform_device *pdev)
+{
+	int rc;
+	int irq;
+	int pcie_irq;
+	u32 memory[2];
+	struct regmap *scu;
+	struct aspeed_xdma *ctx;
+	struct device *dev = &pdev->dev;
+	const void *md = of_device_get_match_data(dev);
+
+	if (!md)
+		return -ENODEV;
+
+	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->chip = md;
+	ctx->dev = dev;
+	platform_set_drvdata(pdev, ctx);
+	mutex_init(&ctx->start_lock);
+	INIT_WORK(&ctx->reset_work, aspeed_xdma_reset_work);
+	spin_lock_init(&ctx->client_lock);
+	spin_lock_init(&ctx->reset_lock);
+	init_waitqueue_head(&ctx->wait);
+
+	ctx->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(ctx->base)) {
+		dev_err(dev, "Failed to map registers.\n");
+		return PTR_ERR(ctx->base);
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(dev, "Unable to find IRQ.\n");
+		return irq;
+	}
+
+	rc = devm_request_irq(dev, irq, aspeed_xdma_irq, IRQF_SHARED,
+			      DEVICE_NAME, ctx);
+	if (rc < 0) {
+		dev_err(dev, "Failed to request IRQ %d.\n", irq);
+		return rc;
+	}
+
+	ctx->clock = devm_clk_get(dev, NULL);
+	if (IS_ERR(ctx->clock)) {
+		dev_err(dev, "Failed to request clock.\n");
+		return PTR_ERR(ctx->clock);
+	}
+
+	ctx->reset = devm_reset_control_get_exclusive(dev, NULL);
+	if (IS_ERR(ctx->reset)) {
+		dev_err(dev, "Failed to request reset control.\n");
+		return PTR_ERR(ctx->reset);
+	}
+
+	ctx->pool = devm_gen_pool_create(dev, ilog2(PAGE_SIZE), -1, NULL);
+	if (!ctx->pool) {
+		dev_err(dev, "Failed to setup genalloc pool.\n");
+		return -ENOMEM;
+	}
+
+	rc = of_property_read_u32_array(dev->of_node, "memory", memory, 2);
+	if (rc) {
+		dev_err(dev, "Unable to get memory space.\n");
+		return rc;
+	}
+
+	ctx->mem_phys = memory[0];
+	ctx->mem_size = memory[1];
+
+	ctx->mem_virt = devm_ioremap(dev, ctx->mem_phys, ctx->mem_size);
+	if (IS_ERR(ctx->mem_virt)) {
+		dev_err(dev, "Failed to map memory space.\n");
+		return PTR_ERR(ctx->mem_virt);
+	}
+
+	rc = gen_pool_add_virt(ctx->pool, (unsigned long)ctx->mem_virt,
+			       ctx->mem_phys, ctx->mem_size, -1);
+	if (rc) {
+		dev_err(ctx->dev, "Failed to add memory to genalloc pool.\n");
+		return rc;
+	}
+
+	scu = syscon_regmap_lookup_by_phandle(dev->of_node, "scu");
+	if (!IS_ERR(scu)) {
+		u32 selection;
+		bool pcie_device_bmc = true;
+		const u32 bmc = SCU_PCIE_CONF_BMC_EN |
+			SCU_PCIE_CONF_BMC_EN_MSI | SCU_PCIE_CONF_BMC_EN_IRQ |
+			SCU_PCIE_CONF_BMC_EN_DMA;
+		const u32 vga = SCU_PCIE_CONF_VGA_EN |
+			SCU_PCIE_CONF_VGA_EN_MSI | SCU_PCIE_CONF_VGA_EN_IRQ |
+			SCU_PCIE_CONF_VGA_EN_DMA;
+		const char *pcie = NULL;
+
+		if (!of_property_read_string(dev->of_node, "pcie-device",
+					     &pcie)) {
+			if (!strcmp(pcie, "vga")) {
+				pcie_device_bmc = false;
+			} else if (strcmp(pcie, "bmc")) {
+				dev_err(ctx->dev,
+					"Invalid pcie-device property %s.\n",
+					pcie);
+				return -EINVAL;
+			}
+		}
+
+		if (pcie_device_bmc) {
+			selection = bmc;
+			regmap_write(scu, ctx->chip->scu_bmc_class,
+				     SCU_BMC_CLASS_REV_XDMA);
+		} else {
+			selection = vga;
+		}
+
+		regmap_update_bits(scu, ctx->chip->scu_pcie_conf, bmc | vga,
+				   selection);
+	} else {
+		dev_warn(dev, "Unable to configure PCIe; continuing.\n");
+	}
+
+	rc = clk_prepare_enable(ctx->clock);
+	if (rc) {
+		dev_err(dev, "Failed to enable the clock.\n");
+		return rc;
+	}
+	msleep(XDMA_RESET_TIME_MS);
+
+	rc = reset_control_deassert(ctx->reset);
+	if (rc) {
+		clk_disable_unprepare(ctx->clock);
+
+		dev_err(dev, "Failed to clear the reset.\n");
+		return rc;
+	}
+	msleep(XDMA_RESET_TIME_MS);
+
+	ctx->cmdq = gen_pool_dma_alloc(ctx->pool, XDMA_CMDQ_SIZE,
+				       &ctx->cmdq_phys);
+	if (!ctx->cmdq) {
+		dev_err(ctx->dev, "Failed to genalloc cmdq.\n");
+
+		reset_control_assert(ctx->reset);
+		clk_disable_unprepare(ctx->clock);
+		return -ENOMEM;
+	}
+
+	aspeed_xdma_init_eng(ctx);
+
+	/*
+	 * This interrupt could fire immediately so only request it once the
+	 * engine and driver are initialized.
+	 */
+	pcie_irq = platform_get_irq(pdev, 1);
+	if (pcie_irq < 0) {
+		dev_warn(dev, "Unable to find PCI-E IRQ.\n");
+	} else {
+		rc = devm_request_irq(dev, pcie_irq, aspeed_xdma_pcie_irq,
+				      IRQF_SHARED, DEVICE_NAME, ctx);
+		if (rc < 0)
+			dev_warn(dev, "Failed to request PCI-E IRQ %d.\n", rc);
+	}
+
+	return 0;
+}
+
+static int aspeed_xdma_remove(struct platform_device *pdev)
+{
+	struct aspeed_xdma *ctx = platform_get_drvdata(pdev);
+
+	gen_pool_free(ctx->pool, (unsigned long)ctx->cmdq_virt,
+		      XDMA_CMDQ_SIZE);
+
+	reset_control_assert(ctx->reset);
+	clk_disable_unprepare(ctx->clock);
+
+	return 0;
+}
+
+static const struct aspeed_xdma_chip aspeed_ast2500_xdma_chip = {
+	.control = XDMA_AST2500_CTRL_US_COMP | XDMA_AST2500_CTRL_DS_COMP |
+		XDMA_AST2500_CTRL_DS_DIRTY | XDMA_AST2500_CTRL_DS_SIZE_256 |
+		XDMA_AST2500_CTRL_DS_TIMEOUT | XDMA_AST2500_CTRL_DS_CHECK_ID,
+	.scu_bmc_class = SCU_AST2500_BMC_CLASS_REV,
+	.scu_pcie_conf = SCU_AST2500_PCIE_CONF,
+	.queue_entry_size = XDMA_AST2500_QUEUE_ENTRY_SIZE,
+	.regs = {
+		.bmc_cmdq_addr = XDMA_AST2500_BMC_CMDQ_ADDR,
+		.bmc_cmdq_endp = XDMA_AST2500_BMC_CMDQ_ENDP,
+		.bmc_cmdq_writep = XDMA_AST2500_BMC_CMDQ_WRITEP,
+		.bmc_cmdq_readp = XDMA_AST2500_BMC_CMDQ_READP,
+		.control = XDMA_AST2500_CTRL,
+		.status = XDMA_AST2500_STATUS,
+	},
+	.status_bits = {
+		.us_comp = XDMA_AST2500_STATUS_US_COMP,
+		.ds_comp = XDMA_AST2500_STATUS_DS_COMP,
+		.ds_dirty = XDMA_AST2500_STATUS_DS_DIRTY,
+	},
+	.set_cmd = aspeed_xdma_ast2500_set_cmd,
+};
+
+static const struct aspeed_xdma_chip aspeed_ast2600_xdma_chip = {
+	.control = XDMA_AST2600_CTRL_US_COMP | XDMA_AST2600_CTRL_DS_COMP |
+		XDMA_AST2600_CTRL_DS_DIRTY | XDMA_AST2600_CTRL_DS_SIZE_256,
+	.scu_bmc_class = SCU_AST2600_BMC_CLASS_REV,
+	.scu_pcie_conf = SCU_AST2600_PCIE_CONF,
+	.queue_entry_size = XDMA_AST2600_QUEUE_ENTRY_SIZE,
+	.regs = {
+		.bmc_cmdq_addr = XDMA_AST2600_BMC_CMDQ_ADDR,
+		.bmc_cmdq_endp = XDMA_AST2600_BMC_CMDQ_ENDP,
+		.bmc_cmdq_writep = XDMA_AST2600_BMC_CMDQ_WRITEP,
+		.bmc_cmdq_readp = XDMA_AST2600_BMC_CMDQ_READP,
+		.control = XDMA_AST2600_CTRL,
+		.status = XDMA_AST2600_STATUS,
+	},
+	.status_bits = {
+		.us_comp = XDMA_AST2600_STATUS_US_COMP,
+		.ds_comp = XDMA_AST2600_STATUS_DS_COMP,
+		.ds_dirty = XDMA_AST2600_STATUS_DS_DIRTY,
+	},
+	.set_cmd = aspeed_xdma_ast2600_set_cmd,
+};
+
+static const struct of_device_id aspeed_xdma_match[] = {
+	{
+		.compatible = "aspeed,ast2500-xdma",
+		.data = &aspeed_ast2500_xdma_chip,
+	},
+	{
+		.compatible = "aspeed,ast2600-xdma",
+		.data = &aspeed_ast2600_xdma_chip,
+	},
+	{ },
+};
+
+static struct platform_driver aspeed_xdma_driver = {
+	.probe = aspeed_xdma_probe,
+	.remove = aspeed_xdma_remove,
+	.driver = {
+		.name = DEVICE_NAME,
+		.of_match_table = aspeed_xdma_match,
+	},
+};
+
+module_platform_driver(aspeed_xdma_driver);
+
+MODULE_AUTHOR("Eddie James");
+MODULE_DESCRIPTION("Aspeed XDMA Engine Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/uapi/linux/aspeed-xdma.h b/include/uapi/linux/aspeed-xdma.h
new file mode 100644
index 000000000000..2efaa6067c39
--- /dev/null
+++ b/include/uapi/linux/aspeed-xdma.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/* Copyright IBM Corp 2019 */
+
+#ifndef _UAPI_LINUX_ASPEED_XDMA_H_
+#define _UAPI_LINUX_ASPEED_XDMA_H_
+
+#include <linux/types.h>
+
+/*
+ * aspeed_xdma_direction
+ *
+ * ASPEED_XDMA_DIRECTION_DOWNSTREAM: transfers data from the host to the BMC
+ *
+ * ASPEED_XDMA_DIRECTION_UPSTREAM: transfers data from the BMC to the host
+ */
+enum aspeed_xdma_direction {
+	ASPEED_XDMA_DIRECTION_DOWNSTREAM = 0,
+	ASPEED_XDMA_DIRECTION_UPSTREAM,
+};
+
+/*
+ * aspeed_xdma_op
+ *
+ * host_addr: the DMA address on the host side, typically configured by PCI
+ *            subsystem
+ *
+ * len: the size of the transfer in bytes
+ *
+ * direction: an enumerator indicating the direction of the DMA operation; see
+ *            enum aspeed_xdma_direction
+ */
+struct aspeed_xdma_op {
+	__u64 host_addr;
+	__u32 len;
+	__u32 direction;
+};
+
+#endif /* _UAPI_LINUX_ASPEED_XDMA_H_ */
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v3 07/12] soc: aspeed: xdma: Add user interface
  2019-12-18 15:09 [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
                   ` (5 preceding siblings ...)
  2019-12-18 15:09 ` [PATCH v3 06/12] soc: aspeed: Add XDMA Engine Driver Eddie James
@ 2019-12-18 15:09 ` Eddie James
  2019-12-19  1:19   ` Andrew Jeffery
  2019-12-18 15:09 ` [PATCH v3 08/12] soc: aspeed: xdma: Add reset ioctl Eddie James
                   ` (4 subsequent siblings)
  11 siblings, 1 reply; 21+ messages in thread
From: Eddie James @ 2019-12-18 15:09 UTC (permalink / raw)
  To: linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, jason, maz, robh+dt,
	tglx, joel, andrew, eajames

This commits adds a miscdevice to provide a user interface to the XDMA
engine. The interface provides the write operation to start DMA
operations. The DMA parameters are passed as the data to the write call.
The actual data to transfer is NOT passed through write. Note that both
directions of DMA operation are accomplished through the write command;
BMC to host and host to BMC.

The XDMA driver reserves an area of physical memory for DMA operations,
as the XDMA engine is restricted to accessing certain physical memory
areas on some platforms. This memory forms a pool from which users can
allocate pages for their usage with calls to mmap. The space allocated
by a client will be the space used in the DMA operation. For an
"upstream" (BMC to host) operation, the data in the client's area will
be transferred to the host. For a "downstream" (host to BMC) operation,
the host data will be placed in the client's memory area.

Poll is also provided in order to determine when the DMA operation is
complete for non-blocking IO.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
Changes since v2:
 - Rework commit message to talk about VGA memory less
 - Remove user reset functionality
 - Clean up sanity checks in aspeed_xdma_write()
 - Wait for transfer complete in the vm area close function

 drivers/soc/aspeed/aspeed-xdma.c | 205 ++++++++++++++++++++++++++++++-
 1 file changed, 203 insertions(+), 2 deletions(-)

diff --git a/drivers/soc/aspeed/aspeed-xdma.c b/drivers/soc/aspeed/aspeed-xdma.c
index cb94adf798b1..e844937dc925 100644
--- a/drivers/soc/aspeed/aspeed-xdma.c
+++ b/drivers/soc/aspeed/aspeed-xdma.c
@@ -13,6 +13,7 @@
 #include <linux/io.h>
 #include <linux/jiffies.h>
 #include <linux/mfd/syscon.h>
+#include <linux/miscdevice.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/of_device.h>
@@ -201,6 +202,8 @@ struct aspeed_xdma {
 	struct clk *clock;
 	struct reset_control *reset;
 
+	/* file_lock serializes reads of current_client */
+	struct mutex file_lock;
 	/* client_lock protects error and in_progress of the client */
 	spinlock_t client_lock;
 	struct aspeed_xdma_client *current_client;
@@ -223,6 +226,8 @@ struct aspeed_xdma {
 	void __iomem *mem_virt;
 	dma_addr_t cmdq_phys;
 	struct gen_pool *pool;
+
+	struct miscdevice misc;
 };
 
 struct aspeed_xdma_client {
@@ -522,6 +527,185 @@ static irqreturn_t aspeed_xdma_pcie_irq(int irq, void *arg)
 	return IRQ_HANDLED;
 }
 
+static ssize_t aspeed_xdma_write(struct file *file, const char __user *buf,
+				 size_t len, loff_t *offset)
+{
+	int rc;
+	struct aspeed_xdma_op op;
+	struct aspeed_xdma_client *client = file->private_data;
+	struct aspeed_xdma *ctx = client->ctx;
+
+	if (len != sizeof(op))
+		return -EINVAL;
+
+	rc = copy_from_user(&op, buf, len);
+	if (rc)
+		return rc;
+
+	if (!op.len || op.len > client->size ||
+	    op.direction > ASPEED_XDMA_DIRECTION_UPSTREAM)
+		return -EINVAL;
+
+	if (file->f_flags & O_NONBLOCK) {
+		if (!mutex_trylock(&ctx->file_lock))
+			return -EAGAIN;
+
+		if (ctx->current_client) {
+			mutex_unlock(&ctx->file_lock);
+			return -EBUSY;
+		}
+	} else {
+		mutex_lock(&ctx->file_lock);
+
+		rc = wait_event_interruptible(ctx->wait, !ctx->current_client);
+		if (rc) {
+			mutex_unlock(&ctx->file_lock);
+			return -EINTR;
+		}
+	}
+
+	aspeed_xdma_start(ctx, &op, client->phys, client);
+
+	mutex_unlock(&ctx->file_lock);
+
+	if (!(file->f_flags & O_NONBLOCK)) {
+		rc = wait_event_interruptible(ctx->wait, !client->in_progress);
+		if (rc)
+			return -EINTR;
+
+		if (client->error)
+			return -EIO;
+	}
+
+	return len;
+}
+
+static __poll_t aspeed_xdma_poll(struct file *file,
+				 struct poll_table_struct *wait)
+{
+	__poll_t mask = 0;
+	__poll_t req = poll_requested_events(wait);
+	struct aspeed_xdma_client *client = file->private_data;
+	struct aspeed_xdma *ctx = client->ctx;
+
+	if (req & (EPOLLIN | EPOLLRDNORM)) {
+		if (client->in_progress)
+			poll_wait(file, &ctx->wait, wait);
+
+		if (!client->in_progress) {
+			if (client->error)
+				mask |= EPOLLERR;
+			else
+				mask |= EPOLLIN | EPOLLRDNORM;
+		}
+	}
+
+	if (req & (EPOLLOUT | EPOLLWRNORM)) {
+		if (ctx->current_client)
+			poll_wait(file, &ctx->wait, wait);
+
+		if (!ctx->current_client)
+			mask |= EPOLLOUT | EPOLLWRNORM;
+	}
+
+	return mask;
+}
+
+static void aspeed_xdma_vma_close(struct vm_area_struct *vma)
+{
+	int rc;
+	struct aspeed_xdma_client *client = vma->vm_private_data;
+
+	rc = wait_event_interruptible(client->ctx->wait, !client->in_progress);
+	if (rc)
+		return;
+
+	gen_pool_free(client->ctx->pool, (unsigned long)client->virt,
+		      client->size);
+
+	client->virt = NULL;
+	client->phys = 0;
+	client->size = 0;
+}
+
+static const struct vm_operations_struct aspeed_xdma_vm_ops = {
+	.close =	aspeed_xdma_vma_close,
+};
+
+static int aspeed_xdma_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	int rc;
+	struct aspeed_xdma_client *client = file->private_data;
+	struct aspeed_xdma *ctx = client->ctx;
+
+	/* restrict file to one mapping */
+	if (client->size)
+		return -EBUSY;
+
+	client->size = vma->vm_end - vma->vm_start;
+	client->virt = gen_pool_dma_alloc(ctx->pool, client->size,
+					  &client->phys);
+	if (!client->virt) {
+		client->phys = 0;
+		client->size = 0;
+		return -ENOMEM;
+	}
+
+	vma->vm_pgoff = (client->phys - ctx->mem_phys) >> PAGE_SHIFT;
+	vma->vm_ops = &aspeed_xdma_vm_ops;
+	vma->vm_private_data = client;
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+	rc = io_remap_pfn_range(vma, vma->vm_start, client->phys >> PAGE_SHIFT,
+				client->size, vma->vm_page_prot);
+	if (rc) {
+		gen_pool_free(ctx->pool, (unsigned long)client->virt,
+			      client->size);
+
+		client->virt = NULL;
+		client->phys = 0;
+		client->size = 0;
+		return rc;
+	}
+
+	dev_dbg(ctx->dev, "mmap: v[%08lx] to p[%08x], s[%08x]\n",
+		vma->vm_start, (u32)client->phys, client->size);
+
+	return 0;
+}
+
+static int aspeed_xdma_open(struct inode *inode, struct file *file)
+{
+	struct miscdevice *misc = file->private_data;
+	struct aspeed_xdma *ctx = container_of(misc, struct aspeed_xdma, misc);
+	struct aspeed_xdma_client *client = kzalloc(sizeof(*client),
+						    GFP_KERNEL);
+
+	if (!client)
+		return -ENOMEM;
+
+	client->ctx = ctx;
+	file->private_data = client;
+	return 0;
+}
+
+static int aspeed_xdma_release(struct inode *inode, struct file *file)
+{
+	struct aspeed_xdma_client *client = file->private_data;
+
+	kfree(client);
+	return 0;
+}
+
+static const struct file_operations aspeed_xdma_fops = {
+	.owner			= THIS_MODULE,
+	.write			= aspeed_xdma_write,
+	.poll			= aspeed_xdma_poll,
+	.mmap			= aspeed_xdma_mmap,
+	.open			= aspeed_xdma_open,
+	.release		= aspeed_xdma_release,
+};
+
 static int aspeed_xdma_probe(struct platform_device *pdev)
 {
 	int rc;
@@ -543,6 +727,7 @@ static int aspeed_xdma_probe(struct platform_device *pdev)
 	ctx->chip = md;
 	ctx->dev = dev;
 	platform_set_drvdata(pdev, ctx);
+	mutex_init(&ctx->file_lock);
 	mutex_init(&ctx->start_lock);
 	INIT_WORK(&ctx->reset_work, aspeed_xdma_reset_work);
 	spin_lock_init(&ctx->client_lock);
@@ -674,6 +859,22 @@ static int aspeed_xdma_probe(struct platform_device *pdev)
 
 	aspeed_xdma_init_eng(ctx);
 
+	ctx->misc.minor = MISC_DYNAMIC_MINOR;
+	ctx->misc.fops = &aspeed_xdma_fops;
+	ctx->misc.name = "aspeed-xdma";
+	ctx->misc.parent = dev;
+	rc = misc_register(&ctx->misc);
+	if (rc) {
+		dev_err(dev, "Failed to register xdma miscdevice.\n");
+
+		gen_pool_free(ctx->pool, (unsigned long)ctx->cmdq,
+			      XDMA_CMDQ_SIZE);
+
+		reset_control_assert(ctx->reset);
+		clk_disable_unprepare(ctx->clock);
+		return rc;
+	}
+
 	/*
 	 * This interrupt could fire immediately so only request it once the
 	 * engine and driver are initialized.
@@ -695,8 +896,8 @@ static int aspeed_xdma_remove(struct platform_device *pdev)
 {
 	struct aspeed_xdma *ctx = platform_get_drvdata(pdev);
 
-	gen_pool_free(ctx->pool, (unsigned long)ctx->cmdq_virt,
-		      XDMA_CMDQ_SIZE);
+	misc_deregister(&ctx->misc);
+	gen_pool_free(ctx->pool, (unsigned long)ctx->cmdq, XDMA_CMDQ_SIZE);
 
 	reset_control_assert(ctx->reset);
 	clk_disable_unprepare(ctx->clock);
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v3 08/12] soc: aspeed: xdma: Add reset ioctl
  2019-12-18 15:09 [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
                   ` (6 preceding siblings ...)
  2019-12-18 15:09 ` [PATCH v3 07/12] soc: aspeed: xdma: Add user interface Eddie James
@ 2019-12-18 15:09 ` Eddie James
  2019-12-18 15:09 ` [PATCH v3 09/12] ARM: dts: aspeed: ast2500: Add XDMA Engine Eddie James
                   ` (3 subsequent siblings)
  11 siblings, 0 replies; 21+ messages in thread
From: Eddie James @ 2019-12-18 15:09 UTC (permalink / raw)
  To: linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, jason, maz, robh+dt,
	tglx, joel, andrew, eajames

Users of the XDMA engine need a way to reset it if something goes wrong.
Problems on the host side, or user error, such as incorrect host
address, may result in the DMA operation never completing and no way to
determine what went wrong. Therefore, add an ioctl to reset the engine
so that users can recover in this situation.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
 drivers/soc/aspeed/aspeed-xdma.c | 36 ++++++++++++++++++++++++++++++++
 include/uapi/linux/aspeed-xdma.h |  4 ++++
 2 files changed, 40 insertions(+)

diff --git a/drivers/soc/aspeed/aspeed-xdma.c b/drivers/soc/aspeed/aspeed-xdma.c
index e844937dc925..21a36b59e718 100644
--- a/drivers/soc/aspeed/aspeed-xdma.c
+++ b/drivers/soc/aspeed/aspeed-xdma.c
@@ -611,6 +611,41 @@ static __poll_t aspeed_xdma_poll(struct file *file,
 	return mask;
 }
 
+static long aspeed_xdma_ioctl(struct file *file, unsigned int cmd,
+			      unsigned long param)
+{
+	unsigned long flags;
+	struct aspeed_xdma_client *client = file->private_data;
+	struct aspeed_xdma *ctx = client->ctx;
+
+	switch (cmd) {
+	case ASPEED_XDMA_IOCTL_RESET:
+		spin_lock_irqsave(&ctx->reset_lock, flags);
+		if (ctx->in_reset) {
+			spin_unlock_irqrestore(&ctx->reset_lock, flags);
+			return 0;
+		}
+
+		ctx->in_reset = true;
+		spin_unlock_irqrestore(&ctx->reset_lock, flags);
+
+		if (ctx->current_client)
+			dev_warn(ctx->dev,
+				 "User reset with transfer in progress.\n");
+
+		mutex_lock(&ctx->start_lock);
+
+		aspeed_xdma_reset(ctx);
+
+		mutex_unlock(&ctx->start_lock);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static void aspeed_xdma_vma_close(struct vm_area_struct *vma)
 {
 	int rc;
@@ -701,6 +736,7 @@ static const struct file_operations aspeed_xdma_fops = {
 	.owner			= THIS_MODULE,
 	.write			= aspeed_xdma_write,
 	.poll			= aspeed_xdma_poll,
+	.unlocked_ioctl		= aspeed_xdma_ioctl,
 	.mmap			= aspeed_xdma_mmap,
 	.open			= aspeed_xdma_open,
 	.release		= aspeed_xdma_release,
diff --git a/include/uapi/linux/aspeed-xdma.h b/include/uapi/linux/aspeed-xdma.h
index 2efaa6067c39..3a3646fd1e9e 100644
--- a/include/uapi/linux/aspeed-xdma.h
+++ b/include/uapi/linux/aspeed-xdma.h
@@ -4,8 +4,12 @@
 #ifndef _UAPI_LINUX_ASPEED_XDMA_H_
 #define _UAPI_LINUX_ASPEED_XDMA_H_
 
+#include <linux/ioctl.h>
 #include <linux/types.h>
 
+#define __ASPEED_XDMA_IOCTL_MAGIC	0xb7
+#define ASPEED_XDMA_IOCTL_RESET		_IO(__ASPEED_XDMA_IOCTL_MAGIC, 0)
+
 /*
  * aspeed_xdma_direction
  *
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v3 09/12] ARM: dts: aspeed: ast2500: Add XDMA Engine
  2019-12-18 15:09 [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
                   ` (7 preceding siblings ...)
  2019-12-18 15:09 ` [PATCH v3 08/12] soc: aspeed: xdma: Add reset ioctl Eddie James
@ 2019-12-18 15:09 ` Eddie James
  2019-12-18 15:09 ` [PATCH v3 10/12] ARM: dts: aspeed: ast2600: " Eddie James
                   ` (2 subsequent siblings)
  11 siblings, 0 replies; 21+ messages in thread
From: Eddie James @ 2019-12-18 15:09 UTC (permalink / raw)
  To: linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, jason, maz, robh+dt,
	tglx, joel, andrew, eajames

Add a node for the XDMA engine with all the necessary information.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
Changes since v2:
 - Remove addition of sdmc stuff

 arch/arm/boot/dts/aspeed-g5.dtsi | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/arm/boot/dts/aspeed-g5.dtsi b/arch/arm/boot/dts/aspeed-g5.dtsi
index 4791a50e37ee..777eeca9c550 100644
--- a/arch/arm/boot/dts/aspeed-g5.dtsi
+++ b/arch/arm/boot/dts/aspeed-g5.dtsi
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 #include <dt-bindings/clock/aspeed-clock.h>
+#include <dt-bindings/interrupt-controller/aspeed-scu-ic.h>
 
 / {
 	model = "Aspeed BMC";
@@ -257,6 +258,17 @@ gfx: display@1e6e6000 {
 				interrupts = <0x19>;
 			};
 
+			xdma: xdma@1e6e7000 {
+				compatible = "aspeed,ast2500-xdma";
+				reg = <0x1e6e7000 0x100>;
+				clocks = <&syscon ASPEED_CLK_GATE_BCLK>;
+				resets = <&syscon ASPEED_RESET_XDMA>;
+				interrupts-extended = <&vic 6>, <&scu_ic ASPEED_AST2500_SCU_IC_PCIE_RESET_LO_TO_HI>;
+				pcie-device = "bmc";
+				scu = <&syscon>;
+				status = "disabled";
+			};
+
 			adc: adc@1e6e9000 {
 				compatible = "aspeed,ast2500-adc";
 				reg = <0x1e6e9000 0xb0>;
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v3 10/12] ARM: dts: aspeed: ast2600: Add XDMA Engine
  2019-12-18 15:09 [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
                   ` (8 preceding siblings ...)
  2019-12-18 15:09 ` [PATCH v3 09/12] ARM: dts: aspeed: ast2500: Add XDMA Engine Eddie James
@ 2019-12-18 15:09 ` Eddie James
  2019-12-18 15:09 ` [PATCH v3 11/12] ARM: dts: aspeed: witherspoon: Enable " Eddie James
  2019-12-18 15:09 ` [PATCH v3 12/12] ARM: dts: aspeed: tacoma: Enable XDMA engine Eddie James
  11 siblings, 0 replies; 21+ messages in thread
From: Eddie James @ 2019-12-18 15:09 UTC (permalink / raw)
  To: linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, jason, maz, robh+dt,
	tglx, joel, andrew, eajames

Add a node for the XDMA engine with all the necessary information.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
Changes since v2:
 - Remove addition of sdmc stuff

 arch/arm/boot/dts/aspeed-g6.dtsi | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/arm/boot/dts/aspeed-g6.dtsi b/arch/arm/boot/dts/aspeed-g6.dtsi
index ead336e93a12..d5ee235790f5 100644
--- a/arch/arm/boot/dts/aspeed-g6.dtsi
+++ b/arch/arm/boot/dts/aspeed-g6.dtsi
@@ -3,6 +3,7 @@
 
 #include <dt-bindings/interrupt-controller/arm-gic.h>
 #include <dt-bindings/clock/ast2600-clock.h>
+#include <dt-bindings/interrupt-controller/aspeed-scu-ic.h>
 
 / {
 	model = "Aspeed BMC";
@@ -311,6 +312,18 @@ rng: hwrng@1e6e2524 {
 				quality = <100>;
 			};
 
+			xdma: xdma@1e6e7000 {
+				compatible = "aspeed,ast2600-xdma";
+				reg = <0x1e6e7000 0x100>;
+				clocks = <&syscon ASPEED_CLK_GATE_BCLK>;
+				resets = <&syscon ASPEED_RESET_DEV_XDMA>;
+				interrupts-extended = <&gic GIC_SPI 6 IRQ_TYPE_LEVEL_HIGH>,
+						      <&scu_ic0 ASPEED_AST2600_SCU_IC0_PCIE_PERST_LO_TO_HI>;
+				pcie-device = "bmc";
+				scu = <&syscon>;
+				status = "disabled";
+			};
+
 			gpio0: gpio@1e780000 {
 				#gpio-cells = <2>;
 				gpio-controller;
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v3 11/12] ARM: dts: aspeed: witherspoon: Enable XDMA Engine
  2019-12-18 15:09 [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
                   ` (9 preceding siblings ...)
  2019-12-18 15:09 ` [PATCH v3 10/12] ARM: dts: aspeed: ast2600: " Eddie James
@ 2019-12-18 15:09 ` Eddie James
  2019-12-18 15:09 ` [PATCH v3 12/12] ARM: dts: aspeed: tacoma: Enable XDMA engine Eddie James
  11 siblings, 0 replies; 21+ messages in thread
From: Eddie James @ 2019-12-18 15:09 UTC (permalink / raw)
  To: linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, jason, maz, robh+dt,
	tglx, joel, andrew, eajames

Enable the XDMA engine node.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
 arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts b/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts
index 569dad93e162..1a28b86f00ea 100644
--- a/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts
+++ b/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts
@@ -658,4 +658,9 @@ &video {
 	memory-region = <&video_engine_memory>;
 };
 
+&xdma {
+	status = "okay";
+	memory = <0x9f000000 0x01000000>;
+};
+
 #include "ibm-power9-dual.dtsi"
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v3 12/12] ARM: dts: aspeed: tacoma: Enable XDMA engine
  2019-12-18 15:09 [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
                   ` (10 preceding siblings ...)
  2019-12-18 15:09 ` [PATCH v3 11/12] ARM: dts: aspeed: witherspoon: Enable " Eddie James
@ 2019-12-18 15:09 ` Eddie James
  11 siblings, 0 replies; 21+ messages in thread
From: Eddie James @ 2019-12-18 15:09 UTC (permalink / raw)
  To: linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, jason, maz, robh+dt,
	tglx, joel, andrew, eajames

Enable the XDMA engine node.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
 arch/arm/boot/dts/aspeed-bmc-opp-tacoma.dts | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/aspeed-bmc-opp-tacoma.dts b/arch/arm/boot/dts/aspeed-bmc-opp-tacoma.dts
index f02de4ab058c..2e5cd51db7c2 100644
--- a/arch/arm/boot/dts/aspeed-bmc-opp-tacoma.dts
+++ b/arch/arm/boot/dts/aspeed-bmc-opp-tacoma.dts
@@ -1193,3 +1193,8 @@ &pinctrl {
 	pinctrl-0 = <&pinctrl_lpc_default>,
 		    <&pinctrl_lsirq_default>;
 };
+
+&xdma {
+	status = "okay";
+	memory = <0xbf800000 0x00800000>;
+};
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* Re: [PATCH v3 03/12] ARM: dts: aspeed: ast2500: Add SCU interrupt controller
  2019-12-18 15:09 ` [PATCH v3 03/12] ARM: dts: aspeed: ast2500: Add " Eddie James
@ 2019-12-18 22:34   ` Andrew Jeffery
  0 siblings, 0 replies; 21+ messages in thread
From: Andrew Jeffery @ 2019-12-18 22:34 UTC (permalink / raw)
  To: Eddie James, linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, Jason Cooper,
	Marc Zyngier, Rob Herring, tglx, Joel Stanley



On Thu, 19 Dec 2019, at 01:39, Eddie James wrote:
> Add a node for the interrupt controller provided by the SCU.
> 
> Signed-off-by: Eddie James <eajames@linux.ibm.com>

Reviewed-by: Andrew Jeffery <andrew@aj.id.au>

^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v3 06/12] soc: aspeed: Add XDMA Engine Driver
  2019-12-18 15:09 ` [PATCH v3 06/12] soc: aspeed: Add XDMA Engine Driver Eddie James
@ 2019-12-18 23:12   ` Andrew Jeffery
  0 siblings, 0 replies; 21+ messages in thread
From: Andrew Jeffery @ 2019-12-18 23:12 UTC (permalink / raw)
  To: Eddie James, linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, Jason Cooper,
	Marc Zyngier, Rob Herring, tglx, Joel Stanley



On Thu, 19 Dec 2019, at 01:39, Eddie James wrote:
> The XDMA engine embedded in the AST2500 and AST2600 SOCs performs PCI
> DMA operations between the SOC (acting as a BMC) and a host processor
> in a server.
> 
> This commit adds a driver to control the XDMA engine and adds functions
> to initialize the hardware and memory and start DMA operations.
> 
> Signed-off-by: Eddie James <eajames@linux.ibm.com>
> ---
> Changes since v2:
>  - Remove SDRAM memory controller configuration
>  - Add client_lock to protect client state
>  - Rename things away from "vga"
>  - Refactor set_cmd and aspeed_xdma_start a bit
>  - Did various suggested cleanup items
> 
>  MAINTAINERS                      |   2 +
>  drivers/soc/aspeed/Kconfig       |   8 +
>  drivers/soc/aspeed/Makefile      |   1 +
>  drivers/soc/aspeed/aspeed-xdma.c | 777 +++++++++++++++++++++++++++++++
>  include/uapi/linux/aspeed-xdma.h |  38 ++
>  5 files changed, 826 insertions(+)
>  create mode 100644 drivers/soc/aspeed/aspeed-xdma.c
>  create mode 100644 include/uapi/linux/aspeed-xdma.h
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 8a14d4268bdc..b72cc581c7a3 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -2713,6 +2713,8 @@ M:	Eddie James <eajames@linux.ibm.com>
>  L:	linux-aspeed@lists.ozlabs.org (moderated for non-subscribers)
>  S:	Maintained
>  F:	Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> +F:	drivers/soc/aspeed/aspeed-xdma.c
> +F:	include/uapi/linux/aspeed-xdma.h
>  
>  ASUS NOTEBOOKS AND EEEPC ACPI/WMI EXTRAS DRIVERS
>  M:	Corentin Chary <corentin.chary@gmail.com>
> diff --git a/drivers/soc/aspeed/Kconfig b/drivers/soc/aspeed/Kconfig
> index 323e177aa74d..2a6c16f9e50b 100644
> --- a/drivers/soc/aspeed/Kconfig
> +++ b/drivers/soc/aspeed/Kconfig
> @@ -29,4 +29,12 @@ config ASPEED_P2A_CTRL
>  	  ioctl()s, the driver also provides an interface for userspace mappings to
>  	  a pre-defined region.
>  
> +config ASPEED_XDMA
> +	tristate "Aspeed XDMA Engine Driver"
> +	depends on SOC_ASPEED && REGMAP && MFD_SYSCON && HAS_DMA
> +	help
> +	  Enable support for the Aspeed XDMA Engine found on the Aspeed AST2XXX
> +	  SOCs. The XDMA engine can perform automatic PCI DMA operations
> +	  between the AST2XXX (acting as a BMC) and a host processor.
> +
>  endmenu
> diff --git a/drivers/soc/aspeed/Makefile b/drivers/soc/aspeed/Makefile
> index b64be47f2b1f..977b046dfb73 100644
> --- a/drivers/soc/aspeed/Makefile
> +++ b/drivers/soc/aspeed/Makefile
> @@ -2,3 +2,4 @@
>  obj-$(CONFIG_ASPEED_LPC_CTRL)	+= aspeed-lpc-ctrl.o
>  obj-$(CONFIG_ASPEED_LPC_SNOOP)	+= aspeed-lpc-snoop.o
>  obj-$(CONFIG_ASPEED_P2A_CTRL)	+= aspeed-p2a-ctrl.o
> +obj-$(CONFIG_ASPEED_XDMA)	+= aspeed-xdma.o
> diff --git a/drivers/soc/aspeed/aspeed-xdma.c b/drivers/soc/aspeed/aspeed-xdma.c
> new file mode 100644
> index 000000000000..cb94adf798b1
> --- /dev/null
> +++ b/drivers/soc/aspeed/aspeed-xdma.c
> @@ -0,0 +1,777 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +// Copyright IBM Corp 2019
> +
> +#include <linux/aspeed-xdma.h>
> +#include <linux/bitfield.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/fs.h>
> +#include <linux/genalloc.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/jiffies.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/poll.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +#include <linux/slab.h>
> +#include <linux/spinlock.h>
> +#include <linux/string.h>
> +#include <linux/uaccess.h>
> +#include <linux/wait.h>
> +#include <linux/workqueue.h>
> +
> +#define DEVICE_NAME				"aspeed-xdma"
> +
> +#define SCU_AST2500_PCIE_CONF			0x180
> +#define SCU_AST2600_PCIE_CONF			0xc20
> +#define  SCU_PCIE_CONF_VGA_EN			 BIT(0)
> +#define  SCU_PCIE_CONF_VGA_EN_MMIO		 BIT(1)
> +#define  SCU_PCIE_CONF_VGA_EN_LPC		 BIT(2)
> +#define  SCU_PCIE_CONF_VGA_EN_MSI		 BIT(3)
> +#define  SCU_PCIE_CONF_VGA_EN_MCTP		 BIT(4)
> +#define  SCU_PCIE_CONF_VGA_EN_IRQ		 BIT(5)
> +#define  SCU_PCIE_CONF_VGA_EN_DMA		 BIT(6)
> +#define  SCU_PCIE_CONF_BMC_EN			 BIT(8)
> +#define  SCU_PCIE_CONF_BMC_EN_MMIO		 BIT(9)
> +#define  SCU_PCIE_CONF_BMC_EN_MSI		 BIT(11)
> +#define  SCU_PCIE_CONF_BMC_EN_MCTP		 BIT(12)
> +#define  SCU_PCIE_CONF_BMC_EN_IRQ		 BIT(13)
> +#define  SCU_PCIE_CONF_BMC_EN_DMA		 BIT(14)
> +
> +#define SCU_AST2500_BMC_CLASS_REV		0x19c
> +#define SCU_AST2600_BMC_CLASS_REV		0xc4c
> +#define  SCU_BMC_CLASS_REV_XDMA			 0xff000001
> +
> +#define XDMA_CMDQ_SIZE				PAGE_SIZE
> +#define XDMA_NUM_CMDS				\
> +	(XDMA_CMDQ_SIZE / sizeof(struct aspeed_xdma_cmd))
> +
> +/* Aspeed specification requires 10ms after switching the reset line */
> +#define XDMA_RESET_TIME_MS			10
> +
> +#define XDMA_CMD_AST2500_PITCH_SHIFT		3
> +#define XDMA_CMD_AST2500_PITCH_BMC		GENMASK_ULL(62, 51)
> +#define XDMA_CMD_AST2500_PITCH_HOST		GENMASK_ULL(46, 35)
> +#define XDMA_CMD_AST2500_PITCH_UPSTREAM		BIT_ULL(31)
> +#define XDMA_CMD_AST2500_PITCH_ADDR		GENMASK_ULL(29, 4)
> +#define XDMA_CMD_AST2500_PITCH_ID		BIT_ULL(0)
> +#define XDMA_CMD_AST2500_CMD_IRQ_EN		BIT_ULL(31)
> +#define XDMA_CMD_AST2500_CMD_LINE_NO		GENMASK_ULL(27, 16)
> +#define XDMA_CMD_AST2500_CMD_IRQ_BMC		BIT_ULL(15)
> +#define XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT	4
> +#define XDMA_CMD_AST2500_CMD_LINE_SIZE		\
> +	GENMASK_ULL(14, XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT)
> +#define XDMA_CMD_AST2500_CMD_ID			BIT_ULL(1)
> +
> +#define XDMA_CMD_AST2600_PITCH_BMC		GENMASK_ULL(62, 48)
> +#define XDMA_CMD_AST2600_PITCH_HOST		GENMASK_ULL(46, 32)
> +#define XDMA_CMD_AST2600_PITCH_ADDR		GENMASK_ULL(30, 0)
> +#define XDMA_CMD_AST2600_CMD_64_EN		BIT_ULL(40)
> +#define XDMA_CMD_AST2600_CMD_IRQ_BMC		BIT_ULL(37)
> +#define XDMA_CMD_AST2600_CMD_IRQ_HOST		BIT_ULL(36)
> +#define XDMA_CMD_AST2600_CMD_UPSTREAM		BIT_ULL(32)
> +#define XDMA_CMD_AST2600_CMD_LINE_NO		GENMASK_ULL(27, 16)
> +#define XDMA_CMD_AST2600_CMD_LINE_SIZE		GENMASK_ULL(14, 0)
> +#define XDMA_CMD_AST2600_CMD_MULTILINE_SIZE	GENMASK_ULL(14, 12)
> +
> +#define XDMA_AST2500_QUEUE_ENTRY_SIZE		4
> +#define XDMA_AST2500_HOST_CMDQ_ADDR0		0x00
> +#define XDMA_AST2500_HOST_CMDQ_ENDP		0x04
> +#define XDMA_AST2500_HOST_CMDQ_WRITEP		0x08
> +#define XDMA_AST2500_HOST_CMDQ_READP		0x0c
> +#define XDMA_AST2500_BMC_CMDQ_ADDR		0x10
> +#define XDMA_AST2500_BMC_CMDQ_ENDP		0x14
> +#define XDMA_AST2500_BMC_CMDQ_WRITEP		0x18
> +#define XDMA_AST2500_BMC_CMDQ_READP		0x1c
> +#define  XDMA_BMC_CMDQ_READP_RESET		 0xee882266
> +#define XDMA_AST2500_CTRL			0x20
> +#define  XDMA_AST2500_CTRL_US_COMP		 BIT(4)
> +#define  XDMA_AST2500_CTRL_DS_COMP		 BIT(5)
> +#define  XDMA_AST2500_CTRL_DS_DIRTY		 BIT(6)
> +#define  XDMA_AST2500_CTRL_DS_SIZE_256		 BIT(17)
> +#define  XDMA_AST2500_CTRL_DS_TIMEOUT		 BIT(28)
> +#define  XDMA_AST2500_CTRL_DS_CHECK_ID		 BIT(29)
> +#define XDMA_AST2500_STATUS			0x24
> +#define  XDMA_AST2500_STATUS_US_COMP		 BIT(4)
> +#define  XDMA_AST2500_STATUS_DS_COMP		 BIT(5)
> +#define  XDMA_AST2500_STATUS_DS_DIRTY		 BIT(6)
> +#define XDMA_AST2500_INPRG_DS_CMD1		0x38
> +#define XDMA_AST2500_INPRG_DS_CMD2		0x3c
> +#define XDMA_AST2500_INPRG_US_CMD00		0x40
> +#define XDMA_AST2500_INPRG_US_CMD01		0x44
> +#define XDMA_AST2500_INPRG_US_CMD10		0x48
> +#define XDMA_AST2500_INPRG_US_CMD11		0x4c
> +#define XDMA_AST2500_INPRG_US_CMD20		0x50
> +#define XDMA_AST2500_INPRG_US_CMD21		0x54
> +#define XDMA_AST2500_HOST_CMDQ_ADDR1		0x60
> +#define XDMA_AST2500_VGA_CMDQ_ADDR0		0x64
> +#define XDMA_AST2500_VGA_CMDQ_ENDP		0x68
> +#define XDMA_AST2500_VGA_CMDQ_WRITEP		0x6c
> +#define XDMA_AST2500_VGA_CMDQ_READP		0x70
> +#define XDMA_AST2500_VGA_CMD_STATUS		0x74
> +#define XDMA_AST2500_VGA_CMDQ_ADDR1		0x78
> +
> +#define XDMA_AST2600_QUEUE_ENTRY_SIZE		2
> +#define XDMA_AST2600_HOST_CMDQ_ADDR0		0x00
> +#define XDMA_AST2600_HOST_CMDQ_ADDR1		0x04
> +#define XDMA_AST2600_HOST_CMDQ_ENDP		0x08
> +#define XDMA_AST2600_HOST_CMDQ_WRITEP		0x0c
> +#define XDMA_AST2600_HOST_CMDQ_READP		0x10
> +#define XDMA_AST2600_BMC_CMDQ_ADDR		0x14
> +#define XDMA_AST2600_BMC_CMDQ_ENDP		0x18
> +#define XDMA_AST2600_BMC_CMDQ_WRITEP		0x1c
> +#define XDMA_AST2600_BMC_CMDQ_READP		0x20
> +#define XDMA_AST2600_VGA_CMDQ_ADDR0		0x24
> +#define XDMA_AST2600_VGA_CMDQ_ADDR1		0x28
> +#define XDMA_AST2600_VGA_CMDQ_ENDP		0x2c
> +#define XDMA_AST2600_VGA_CMDQ_WRITEP		0x30
> +#define XDMA_AST2600_VGA_CMDQ_READP		0x34
> +#define XDMA_AST2600_CTRL			0x38
> +#define  XDMA_AST2600_CTRL_US_COMP		 BIT(16)
> +#define  XDMA_AST2600_CTRL_DS_COMP		 BIT(17)
> +#define  XDMA_AST2600_CTRL_DS_DIRTY		 BIT(18)
> +#define  XDMA_AST2600_CTRL_DS_SIZE_256		 BIT(20)
> +#define XDMA_AST2600_STATUS			0x3c
> +#define  XDMA_AST2600_STATUS_US_COMP		 BIT(16)
> +#define  XDMA_AST2600_STATUS_DS_COMP		 BIT(17)
> +#define  XDMA_AST2600_STATUS_DS_DIRTY		 BIT(18)
> +#define XDMA_AST2600_INPRG_DS_CMD00		0x40
> +#define XDMA_AST2600_INPRG_DS_CMD01		0x44
> +#define XDMA_AST2600_INPRG_DS_CMD10		0x48
> +#define XDMA_AST2600_INPRG_DS_CMD11		0x4c
> +#define XDMA_AST2600_INPRG_DS_CMD20		0x50
> +#define XDMA_AST2600_INPRG_DS_CMD21		0x54
> +#define XDMA_AST2600_INPRG_US_CMD00		0x60
> +#define XDMA_AST2600_INPRG_US_CMD01		0x64
> +#define XDMA_AST2600_INPRG_US_CMD10		0x68
> +#define XDMA_AST2600_INPRG_US_CMD11		0x6c
> +#define XDMA_AST2600_INPRG_US_CMD20		0x70
> +#define XDMA_AST2600_INPRG_US_CMD21		0x74
> +
> +struct aspeed_xdma_cmd {
> +	u64 host_addr;
> +	u64 pitch;
> +	u64 cmd;
> +	u64 reserved;
> +};
> +
> +struct aspeed_xdma_regs {
> +	u8 bmc_cmdq_addr;
> +	u8 bmc_cmdq_endp;
> +	u8 bmc_cmdq_writep;
> +	u8 bmc_cmdq_readp;
> +	u8 control;
> +	u8 status;
> +};
> +
> +struct aspeed_xdma_status_bits {
> +	u32 us_comp;
> +	u32 ds_comp;
> +	u32 ds_dirty;
> +};
> +
> +struct aspeed_xdma;
> +
> +struct aspeed_xdma_chip {
> +	u32 control;
> +	u32 scu_bmc_class;
> +	u32 scu_pcie_conf;
> +	unsigned int queue_entry_size;
> +	struct aspeed_xdma_regs regs;
> +	struct aspeed_xdma_status_bits status_bits;
> +	unsigned int (*set_cmd)(struct aspeed_xdma *ctx,
> +				struct aspeed_xdma_cmd *cmds,

You could (should) declare cmds as `struct aspeed_xdma_cmd cmds[2]` - this
makes it easier to validate assumptions in the code below.

> +				struct aspeed_xdma_op *op, u32 bmc_addr);
> +};
> +
> +struct aspeed_xdma_client;
> +
> +struct aspeed_xdma {
> +	const struct aspeed_xdma_chip *chip;
> +
> +	struct device *dev;
> +	void __iomem *base;
> +	struct clk *clock;
> +	struct reset_control *reset;
> +
> +	/* client_lock protects error and in_progress of the client */
> +	spinlock_t client_lock;
> +	struct aspeed_xdma_client *current_client;
> +
> +	/* start_lock protects cmd_idx, cmdq, and the state of the engine */
> +	struct mutex start_lock;
> +	struct aspeed_xdma_cmd *cmdq;
> +	bool upstream;
> +	unsigned int cmd_idx;
> +
> +	/* reset_lock protects in_reset and the reset state of the engine */
> +	spinlock_t reset_lock;
> +	bool in_reset;
> +
> +	wait_queue_head_t wait;
> +	struct work_struct reset_work;
> +
> +	u32 mem_phys;
> +	u32 mem_size;
> +	void __iomem *mem_virt;
> +	dma_addr_t cmdq_phys;
> +	struct gen_pool *pool;
> +};
> +
> +struct aspeed_xdma_client {
> +	struct aspeed_xdma *ctx;
> +
> +	bool error;
> +	bool in_progress;
> +	void *virt;
> +	dma_addr_t phys;
> +	u32 size;
> +};
> +
> +static u32 aspeed_xdma_readl(struct aspeed_xdma *ctx, u8 reg)
> +{
> +	u32 v = readl(ctx->base + reg);
> +
> +	dev_dbg(ctx->dev, "read %02x[%08x]\n", reg, v);
> +	return v;
> +}
> +
> +static void aspeed_xdma_writel(struct aspeed_xdma *ctx, u8 reg, u32 val)
> +{
> +	writel(val, ctx->base + reg);
> +	dev_dbg(ctx->dev, "write %02x[%08x]\n", reg, val);
> +}
> +
> +static void aspeed_xdma_init_eng(struct aspeed_xdma *ctx)
> +{
> +	aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_endp,
> +			   ctx->chip->queue_entry_size * XDMA_NUM_CMDS);
> +	aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_readp,
> +			   XDMA_BMC_CMDQ_READP_RESET);
> +	aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_writep, 0);
> +	aspeed_xdma_writel(ctx, ctx->chip->regs.control, ctx->chip->control);
> +	aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_addr, ctx->cmdq_phys);
> +
> +	ctx->cmd_idx = 0;
> +	ctx->current_client = NULL;
> +}
> +
> +static unsigned int aspeed_xdma_ast2500_set_cmd(struct aspeed_xdma *ctx,
> +						struct aspeed_xdma_cmd *cmds,
> +						struct aspeed_xdma_op *op,
> +						u32 bmc_addr)
> +{
> +	unsigned int rc = 1;
> +	unsigned int pitch = 1;
> +	unsigned int line_no = 1;
> +	unsigned int line_size = op->len >>
> +		XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT;
> +	u64 cmd = XDMA_CMD_AST2500_CMD_IRQ_EN | XDMA_CMD_AST2500_CMD_IRQ_BMC |
> +		XDMA_CMD_AST2500_CMD_ID;
> +	u64 cmd_pitch = (op->direction ? XDMA_CMD_AST2500_PITCH_UPSTREAM : 0) |
> +		XDMA_CMD_AST2500_PITCH_ID;
> +
> +	dev_dbg(ctx->dev, "xdma %s ast2500: bmc[%08x] len[%08x] host[%08x]\n",
> +		op->direction ? "upstream" : "downstream", bmc_addr, op->len,
> +		(u32)op->host_addr);
> +
> +	if (op->len > XDMA_CMD_AST2500_CMD_LINE_SIZE) {
> +		unsigned int rem;
> +		unsigned int total;
> +
> +		line_no = op->len / XDMA_CMD_AST2500_CMD_LINE_SIZE;
> +		total = XDMA_CMD_AST2500_CMD_LINE_SIZE * line_no;
> +		rem = (op->len - total) >>
> +			XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT;
> +		line_size = XDMA_CMD_AST2500_CMD_LINE_SIZE;
> +		pitch = line_size >> XDMA_CMD_AST2500_PITCH_SHIFT;
> +		line_size >>= XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT;
> +
> +		if (rem) {
> +			u32 rbmc = bmc_addr + total;
> +
> +			cmds[1].host_addr = op->host_addr + (u64)total;

Here is when it becomes easier to validate the behaviour of the code wrt the cmds
declaration I mentioned above. I read this and my first question was "how do we
know that cmds[1] is valid memory?" The nice thing about declaring it in the way I
suggest is that the compiler will enforce correctness for us.

> +			cmds[1].pitch = cmd_pitch |
> +				((u64)rbmc & XDMA_CMD_AST2500_PITCH_ADDR) |
> +				FIELD_PREP(XDMA_CMD_AST2500_PITCH_HOST, 1) |
> +				FIELD_PREP(XDMA_CMD_AST2500_PITCH_BMC, 1);
> +			cmds[1].cmd = cmd |
> +				FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_NO, 1) |
> +				FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_SIZE,
> +					   rem);
> +			cmds[1].reserved = 0ULL;
> +
> +			print_hex_dump_debug("xdma rem ", DUMP_PREFIX_OFFSET,
> +					     16, 1, &cmds[1], sizeof(*cmds),
> +					     true);
> +
> +			cmd &= ~(XDMA_CMD_AST2500_CMD_IRQ_EN |
> +				 XDMA_CMD_AST2500_CMD_IRQ_BMC);
> +
> +			rc++;
> +		}
> +	}
> +
> +	cmds[0].host_addr = op->host_addr;
> +	cmds[0].pitch = cmd_pitch |
> +		((u64)bmc_addr & XDMA_CMD_AST2500_PITCH_ADDR) |
> +		FIELD_PREP(XDMA_CMD_AST2500_PITCH_HOST, pitch) |
> +		FIELD_PREP(XDMA_CMD_AST2500_PITCH_BMC, pitch);
> +	cmds[0].cmd = cmd | FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_NO, line_no) |
> +		FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_SIZE, line_size);
> +	cmds[0].reserved = 0ULL;
> +
> +	print_hex_dump_debug("xdma cmd ", DUMP_PREFIX_OFFSET, 16, 1, cmds,
> +			     sizeof(*cmds), true);
> +
> +	return rc;
> +}
> +
> +static unsigned int aspeed_xdma_ast2600_set_cmd(struct aspeed_xdma *ctx,
> +						struct aspeed_xdma_cmd *cmds,
> +						struct aspeed_xdma_op *op,
> +						u32 bmc_addr)
> +{
> +	unsigned int rc = 1;
> +	unsigned int pitch = 1;
> +	unsigned int line_no = 1;
> +	unsigned int line_size = op->len;
> +	u64 cmd = XDMA_CMD_AST2600_CMD_IRQ_BMC |
> +		(op->direction ? XDMA_CMD_AST2600_CMD_UPSTREAM : 0);
> +
> +	if (op->host_addr & 0xffffffff00000000ULL ||
> +	    (op->host_addr + (u64)op->len) & 0xffffffff00000000ULL)
> +		cmd |= XDMA_CMD_AST2600_CMD_64_EN;
> +
> +	dev_dbg(ctx->dev, "xdma %s ast2600: bmc[%08x] len[%08x] "
> +		"host[%016llx]\n", op->direction ? "upstream" : "downstream",
> +		bmc_addr, op->len, op->host_addr);
> +
> +	if (op->len > XDMA_CMD_AST2600_CMD_LINE_SIZE) {
> +		unsigned int rem;
> +		unsigned int total;
> +
> +		line_no = op->len / XDMA_CMD_AST2600_CMD_MULTILINE_SIZE;
> +		total = XDMA_CMD_AST2600_CMD_MULTILINE_SIZE * line_no;
> +		rem = op->len - total;
> +		line_size = XDMA_CMD_AST2600_CMD_MULTILINE_SIZE;
> +		pitch = line_size;
> +
> +		if (rem) {
> +			u32 rbmc = bmc_addr + total;
> +
> +			cmds[1].host_addr = op->host_addr + (u64)total;
> +			cmds[1].pitch =
> +				((u64)rbmc & XDMA_CMD_AST2600_PITCH_ADDR) |
> +				FIELD_PREP(XDMA_CMD_AST2600_PITCH_HOST, 1) |
> +				FIELD_PREP(XDMA_CMD_AST2600_PITCH_BMC, 1);
> +			cmds[1].cmd = cmd |
> +				FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_NO, 1) |
> +				FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_SIZE,
> +					   rem);
> +			cmds[1].reserved = 0ULL;
> +
> +			print_hex_dump_debug("xdma rem ", DUMP_PREFIX_OFFSET,
> +					     16, 1, &cmds[1], sizeof(*cmds),
> +					     true);
> +
> +			cmd &= ~XDMA_CMD_AST2600_CMD_IRQ_BMC;
> +
> +			rc++;
> +		}
> +	}
> +
> +	cmds[0].host_addr = op->host_addr;
> +	cmds[0].pitch = ((u64)bmc_addr & XDMA_CMD_AST2600_PITCH_ADDR) |
> +		FIELD_PREP(XDMA_CMD_AST2600_PITCH_HOST, pitch) |
> +		FIELD_PREP(XDMA_CMD_AST2600_PITCH_BMC, pitch);
> +	cmds[0].cmd = cmd | FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_NO, line_no) |
> +		FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_SIZE, line_size);
> +	cmds[0].reserved = 0ULL;
> +
> +	print_hex_dump_debug("xdma cmd ", DUMP_PREFIX_OFFSET, 16, 1, cmds,
> +			     sizeof(*cmds), true);
> +
> +	return rc;
> +}
> +
> +static void aspeed_xdma_start(struct aspeed_xdma *ctx,
> +			      struct aspeed_xdma_op *op, u32 bmc_addr,
> +			      struct aspeed_xdma_client *client)
> +{
> +	unsigned long flags;
> +	struct aspeed_xdma_cmd cmds[2];
> +	unsigned int rc = ctx->chip->set_cmd(ctx, cmds, op, bmc_addr);
> +
> +	mutex_lock(&ctx->start_lock);
> +
> +	memcpy(&ctx->cmdq[ctx->cmd_idx], cmds,
> +	       rc * sizeof(struct aspeed_xdma_cmd));
> +	ctx->cmd_idx = (ctx->cmd_idx + rc) % XDMA_NUM_CMDS;
> +	ctx->upstream = !!op->direction;
> +
> +	spin_lock_irqsave(&ctx->client_lock, flags);
> +
> +	client->error = false;
> +	client->in_progress = true;
> +	ctx->current_client = client;
> +
> +	spin_unlock_irqrestore(&ctx->client_lock, flags);
> +
> +	aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_writep,
> +			   ctx->cmd_idx * ctx->chip->queue_entry_size);
> +
> +	mutex_unlock(&ctx->start_lock);
> +}
> +
> +static void aspeed_xdma_done(struct aspeed_xdma *ctx, bool error)
> +{
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&ctx->client_lock, flags);
> +
> +	if (ctx->current_client) {
> +		ctx->current_client->error = error;
> +		ctx->current_client->in_progress = false;
> +		ctx->current_client = NULL;
> +	}
> +
> +	spin_unlock_irqrestore(&ctx->client_lock, flags);
> +
> +	wake_up_interruptible_all(&ctx->wait);
> +}
> +
> +static irqreturn_t aspeed_xdma_irq(int irq, void *arg)
> +{
> +	struct aspeed_xdma *ctx = arg;
> +	u32 status = aspeed_xdma_readl(ctx, ctx->chip->regs.status);
> +
> +	if (status & ctx->chip->status_bits.ds_dirty) {
> +		aspeed_xdma_done(ctx, true);
> +	} else {
> +		if (status & ctx->chip->status_bits.us_comp) {
> +			if (ctx->upstream)
> +				aspeed_xdma_done(ctx, false);
> +		}
> +
> +		if (status & ctx->chip->status_bits.ds_comp) {
> +			if (!ctx->upstream)
> +				aspeed_xdma_done(ctx, false);
> +		}
> +	}
> +
> +	aspeed_xdma_writel(ctx, ctx->chip->regs.status, status);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void aspeed_xdma_reset(struct aspeed_xdma *ctx)
> +{
> +	reset_control_assert(ctx->reset);
> +	msleep(XDMA_RESET_TIME_MS);
> +
> +	reset_control_deassert(ctx->reset);
> +	msleep(XDMA_RESET_TIME_MS);
> +
> +	aspeed_xdma_init_eng(ctx);
> +

unsigned long flags;

spin_lock_irqsave(&ctx->reset_lock, flags);

> +	ctx->in_reset = false;

spin_unlock_irqrestore(&ctx->reset_lock, flags);

> +	aspeed_xdma_done(ctx, true);
> +}
> +
> +static void aspeed_xdma_reset_work(struct work_struct *work)
> +{
> +	struct aspeed_xdma *ctx = container_of(work, struct aspeed_xdma,
> +					       reset_work);
> +
> +	/*
> +	 * Lock to make sure operations aren't started while the engine is
> +	 * in reset.
> +	 */
> +	mutex_lock(&ctx->start_lock);
> +
> +	aspeed_xdma_reset(ctx);
> +
> +	mutex_unlock(&ctx->start_lock);
> +}
> +
> +static irqreturn_t aspeed_xdma_pcie_irq(int irq, void *arg)
> +{
> +	unsigned long flags;
> +	struct aspeed_xdma *ctx = arg;
> +
> +	dev_dbg(ctx->dev, "pcie reset\n");
> +
> +	spin_lock_irqsave(&ctx->reset_lock, flags);
> +	if (ctx->in_reset) {
> +		spin_unlock_irqrestore(&ctx->reset_lock, flags);
> +		return IRQ_HANDLED;
> +	}
> +
> +	ctx->in_reset = true;
> +	spin_unlock_irqrestore(&ctx->reset_lock, flags);
> +
> +	schedule_work(&ctx->reset_work);
> +	return IRQ_HANDLED;
> +}
> +
> +static int aspeed_xdma_probe(struct platform_device *pdev)
> +{
> +	int rc;
> +	int irq;
> +	int pcie_irq;
> +	u32 memory[2];
> +	struct regmap *scu;
> +	struct aspeed_xdma *ctx;
> +	struct device *dev = &pdev->dev;
> +	const void *md = of_device_get_match_data(dev);
> +
> +	if (!md)
> +		return -ENODEV;
> +
> +	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
> +	if (!ctx)
> +		return -ENOMEM;
> +
> +	ctx->chip = md;
> +	ctx->dev = dev;
> +	platform_set_drvdata(pdev, ctx);
> +	mutex_init(&ctx->start_lock);
> +	INIT_WORK(&ctx->reset_work, aspeed_xdma_reset_work);
> +	spin_lock_init(&ctx->client_lock);
> +	spin_lock_init(&ctx->reset_lock);
> +	init_waitqueue_head(&ctx->wait);
> +
> +	ctx->base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(ctx->base)) {
> +		dev_err(dev, "Failed to map registers.\n");
> +		return PTR_ERR(ctx->base);
> +	}
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0) {
> +		dev_err(dev, "Unable to find IRQ.\n");
> +		return irq;
> +	}
> +
> +	rc = devm_request_irq(dev, irq, aspeed_xdma_irq, IRQF_SHARED,

We don't need IRQF_SHARED as far as I can see.

> +			      DEVICE_NAME, ctx);
> +	if (rc < 0) {
> +		dev_err(dev, "Failed to request IRQ %d.\n", irq);
> +		return rc;
> +	}
> +
> +	ctx->clock = devm_clk_get(dev, NULL);
> +	if (IS_ERR(ctx->clock)) {
> +		dev_err(dev, "Failed to request clock.\n");
> +		return PTR_ERR(ctx->clock);
> +	}
> +
> +	ctx->reset = devm_reset_control_get_exclusive(dev, NULL);
> +	if (IS_ERR(ctx->reset)) {
> +		dev_err(dev, "Failed to request reset control.\n");
> +		return PTR_ERR(ctx->reset);
> +	}
> +
> +	ctx->pool = devm_gen_pool_create(dev, ilog2(PAGE_SIZE), -1, NULL);
> +	if (!ctx->pool) {
> +		dev_err(dev, "Failed to setup genalloc pool.\n");
> +		return -ENOMEM;
> +	}
> +
> +	rc = of_property_read_u32_array(dev->of_node, "memory", memory, 2);

See comment on the binding about switching to a reserved memory phandle.

> +	if (rc) {
> +		dev_err(dev, "Unable to get memory space.\n");
> +		return rc;
> +	}
> +
> +	ctx->mem_phys = memory[0];
> +	ctx->mem_size = memory[1];
> +
> +	ctx->mem_virt = devm_ioremap(dev, ctx->mem_phys, ctx->mem_size);
> +	if (IS_ERR(ctx->mem_virt)) {
> +		dev_err(dev, "Failed to map memory space.\n");
> +		return PTR_ERR(ctx->mem_virt);
> +	}
> +
> +	rc = gen_pool_add_virt(ctx->pool, (unsigned long)ctx->mem_virt,
> +			       ctx->mem_phys, ctx->mem_size, -1);
> +	if (rc) {
> +		dev_err(ctx->dev, "Failed to add memory to genalloc pool.\n");
> +		return rc;
> +	}
> +
> +	scu = syscon_regmap_lookup_by_phandle(dev->of_node, "scu");
> +	if (!IS_ERR(scu)) {
> +		u32 selection;
> +		bool pcie_device_bmc = true;
> +		const u32 bmc = SCU_PCIE_CONF_BMC_EN |
> +			SCU_PCIE_CONF_BMC_EN_MSI | SCU_PCIE_CONF_BMC_EN_IRQ |
> +			SCU_PCIE_CONF_BMC_EN_DMA;
> +		const u32 vga = SCU_PCIE_CONF_VGA_EN |
> +			SCU_PCIE_CONF_VGA_EN_MSI | SCU_PCIE_CONF_VGA_EN_IRQ |
> +			SCU_PCIE_CONF_VGA_EN_DMA;
> +		const char *pcie = NULL;
> +
> +		if (!of_property_read_string(dev->of_node, "pcie-device",
> +					     &pcie)) {
> +			if (!strcmp(pcie, "vga")) {
> +				pcie_device_bmc = false;
> +			} else if (strcmp(pcie, "bmc")) {
> +				dev_err(ctx->dev,
> +					"Invalid pcie-device property %s.\n",
> +					pcie);
> +				return -EINVAL;
> +			}
> +		}
> +
> +		if (pcie_device_bmc) {
> +			selection = bmc;
> +			regmap_write(scu, ctx->chip->scu_bmc_class,
> +				     SCU_BMC_CLASS_REV_XDMA);
> +		} else {
> +			selection = vga;
> +		}
> +
> +		regmap_update_bits(scu, ctx->chip->scu_pcie_conf, bmc | vga,
> +				   selection);
> +	} else {
> +		dev_warn(dev, "Unable to configure PCIe; continuing.\n");
> +	}

Bit of a nit, but I think probe would be more readable if we moved the above
out to a helper function.

Looking good though!

Andrew

^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v3 05/12] dt-bindings: soc: Add Aspeed XDMA Engine
  2019-12-18 15:09 ` [PATCH v3 05/12] dt-bindings: soc: Add Aspeed XDMA Engine Eddie James
@ 2019-12-18 23:12   ` Andrew Jeffery
  2019-12-19 15:48     ` Eddie James
  0 siblings, 1 reply; 21+ messages in thread
From: Andrew Jeffery @ 2019-12-18 23:12 UTC (permalink / raw)
  To: Eddie James, linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, Jason Cooper,
	Marc Zyngier, Rob Herring, tglx, Joel Stanley



On Thu, 19 Dec 2019, at 01:39, Eddie James wrote:
> Document the bindings for the Aspeed AST25XX and AST26XX XDMA engine.
> 
> Signed-off-by: Eddie James <eajames@linux.ibm.com>
> Reviewed-by: Rob Herring <robh@kernel.org>
> ---
> Changes since v2:
>  - Remove 'sdmc', rename 'vga-mem' to 'memory'
> 
>  .../devicetree/bindings/soc/aspeed/xdma.txt   | 40 +++++++++++++++++++
>  MAINTAINERS                                   |  6 +++
>  2 files changed, 46 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> 
> diff --git a/Documentation/devicetree/bindings/soc/aspeed/xdma.txt 
> b/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> new file mode 100644
> index 000000000000..58253ea1587b
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> @@ -0,0 +1,40 @@
> +Aspeed AST25XX and AST26XX XDMA Engine
> +
> +The XDMA Engine embedded in the AST2500 and AST2600 SOCs can perform 
> automatic
> +DMA operations over PCI between the SOC (acting as a BMC) and a host 
> processor.
> +
> +Required properties:
> + - compatible		: must be "aspeed,ast2500-xdma" or
> +			  "aspeed,ast2600-xdma"
> + - reg			: contains the address and size of the memory region
> +			  associated with the XDMA engine registers
> + - clocks		: clock specifier for the clock associated with the
> +			  XDMA engine
> + - resets		: reset specifier for the syscon reset associated with
> +			  the XDMA engine
> + - interrupts-extended	: two interrupt cells; the first specifies the 
> global
> +			  interrupt for the XDMA engine and the second
> +			  specifies the PCI-E reset or PERST interrupt.
> + - scu			: a phandle to the syscon node for the system control
> +			  unit of the SOC

I think this should be aspeed,scu.

> + - memory		: contains the address and size of the memory area to
> +			  be used by the XDMA engine for DMA operations

Hmm, I was thinking more like a phandle to a reserved memory region,
like we have in the aspeed-lpc-ctrl binding.

> +
> +Optional properties:
> + - pcie-device		: should be either "bmc" or "vga", corresponding to
> +			  which device should be used by the XDMA engine for
> +			  DMA operations. If this property is not set, the XDMA
> +			  engine will use the BMC PCI-E device.
> +
> +Example:
> +
> +    xdma@1e6e7000 {
> +        compatible = "aspeed,ast2500-xdma";
> +        reg = <0x1e6e7000 0x100>;
> +        clocks = <&syscon ASPEED_CLK_GATE_BCLK>;
> +        resets = <&syscon ASPEED_RESET_XDMA>;
> +        interrupts-extended = <&vic 6>, <&scu_ic 
> ASPEED_AST2500_SCU_IC_PCIE_RESET_LO_TO_HI>;
> +        scu = <&syscon>;
> +        pcie-device = "bmc";
> +        memory = <0x9f000000 0x01000000>;
> +    };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index ac9c120d192b..8a14d4268bdc 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -2708,6 +2708,12 @@ S:	Maintained
>  F:	drivers/media/platform/aspeed-video.c
>  F:	Documentation/devicetree/bindings/media/aspeed-video.txt
>  
> +ASPEED XDMA ENGINE DRIVER
> +M:	Eddie James <eajames@linux.ibm.com>
> +L:	linux-aspeed@lists.ozlabs.org (moderated for non-subscribers)
> +S:	Maintained
> +F:	Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> +
>  ASUS NOTEBOOKS AND EEEPC ACPI/WMI EXTRAS DRIVERS
>  M:	Corentin Chary <corentin.chary@gmail.com>
>  L:	acpi4asus-user@lists.sourceforge.net
> -- 
> 2.24.0
> 
>

^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v3 07/12] soc: aspeed: xdma: Add user interface
  2019-12-18 15:09 ` [PATCH v3 07/12] soc: aspeed: xdma: Add user interface Eddie James
@ 2019-12-19  1:19   ` Andrew Jeffery
  2019-12-19 16:00     ` Eddie James
  0 siblings, 1 reply; 21+ messages in thread
From: Andrew Jeffery @ 2019-12-19  1:19 UTC (permalink / raw)
  To: Eddie James, linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, Jason Cooper,
	Marc Zyngier, Rob Herring, tglx, Joel Stanley



On Thu, 19 Dec 2019, at 01:39, Eddie James wrote:
> This commits adds a miscdevice to provide a user interface to the XDMA
> engine. The interface provides the write operation to start DMA
> operations. The DMA parameters are passed as the data to the write call.
> The actual data to transfer is NOT passed through write. Note that both
> directions of DMA operation are accomplished through the write command;
> BMC to host and host to BMC.
> 
> The XDMA driver reserves an area of physical memory for DMA operations,
> as the XDMA engine is restricted to accessing certain physical memory
> areas on some platforms. This memory forms a pool from which users can
> allocate pages for their usage with calls to mmap. The space allocated
> by a client will be the space used in the DMA operation. For an
> "upstream" (BMC to host) operation, the data in the client's area will
> be transferred to the host. For a "downstream" (host to BMC) operation,
> the host data will be placed in the client's memory area.
> 
> Poll is also provided in order to determine when the DMA operation is
> complete for non-blocking IO.
> 
> Signed-off-by: Eddie James <eajames@linux.ibm.com>
> ---
> Changes since v2:
>  - Rework commit message to talk about VGA memory less
>  - Remove user reset functionality
>  - Clean up sanity checks in aspeed_xdma_write()
>  - Wait for transfer complete in the vm area close function
> 
>  drivers/soc/aspeed/aspeed-xdma.c | 205 ++++++++++++++++++++++++++++++-
>  1 file changed, 203 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/soc/aspeed/aspeed-xdma.c b/drivers/soc/aspeed/aspeed-xdma.c
> index cb94adf798b1..e844937dc925 100644
> --- a/drivers/soc/aspeed/aspeed-xdma.c
> +++ b/drivers/soc/aspeed/aspeed-xdma.c
> @@ -13,6 +13,7 @@
>  #include <linux/io.h>
>  #include <linux/jiffies.h>
>  #include <linux/mfd/syscon.h>
> +#include <linux/miscdevice.h>
>  #include <linux/module.h>
>  #include <linux/mutex.h>
>  #include <linux/of_device.h>
> @@ -201,6 +202,8 @@ struct aspeed_xdma {
>  	struct clk *clock;
>  	struct reset_control *reset;
>  
> +	/* file_lock serializes reads of current_client */
> +	struct mutex file_lock;

I wonder whether start_lock can serve this purpose.

>  	/* client_lock protects error and in_progress of the client */
>  	spinlock_t client_lock;
>  	struct aspeed_xdma_client *current_client;
> @@ -223,6 +226,8 @@ struct aspeed_xdma {
>  	void __iomem *mem_virt;
>  	dma_addr_t cmdq_phys;
>  	struct gen_pool *pool;
> +
> +	struct miscdevice misc;
>  };
>  
>  struct aspeed_xdma_client {
> @@ -522,6 +527,185 @@ static irqreturn_t aspeed_xdma_pcie_irq(int irq, 
> void *arg)
>  	return IRQ_HANDLED;
>  }
>  
> +static ssize_t aspeed_xdma_write(struct file *file, const char __user *buf,
> +				 size_t len, loff_t *offset)
> +{
> +	int rc;
> +	struct aspeed_xdma_op op;
> +	struct aspeed_xdma_client *client = file->private_data;
> +	struct aspeed_xdma *ctx = client->ctx;
> +
> +	if (len != sizeof(op))
> +		return -EINVAL;
> +
> +	rc = copy_from_user(&op, buf, len);
> +	if (rc)
> +		return rc;
> +
> +	if (!op.len || op.len > client->size ||
> +	    op.direction > ASPEED_XDMA_DIRECTION_UPSTREAM)
> +		return -EINVAL;
> +
> +	if (file->f_flags & O_NONBLOCK) {
> +		if (!mutex_trylock(&ctx->file_lock))
> +			return -EAGAIN;
> +
> +		if (ctx->current_client) {

Should be tested under client_lock for consistency with the previous patch,
though perhaps you could use READ_ONCE()?

> +			mutex_unlock(&ctx->file_lock);
> +			return -EBUSY;
> +		}
> +	} else {
> +		mutex_lock(&ctx->file_lock);
> +
> +		rc = wait_event_interruptible(ctx->wait, !ctx->current_client);
> +		if (rc) {
> +			mutex_unlock(&ctx->file_lock);
> +			return -EINTR;
> +		}
> +	}
> +
> +	aspeed_xdma_start(ctx, &op, client->phys, client);
> +
> +	mutex_unlock(&ctx->file_lock);

Shouldn't we lift start_lock out of aspeed_xdma_start() use that here
instead of file_lock? I think that would mean that we could remove
file_lock.

> +
> +	if (!(file->f_flags & O_NONBLOCK)) {
> +		rc = wait_event_interruptible(ctx->wait, !client->in_progress);
> +		if (rc)
> +			return -EINTR;
> +
> +		if (client->error)
> +			return -EIO;
> +	}
> +
> +	return len;
> +}
> +
> +static __poll_t aspeed_xdma_poll(struct file *file,
> +				 struct poll_table_struct *wait)
> +{
> +	__poll_t mask = 0;
> +	__poll_t req = poll_requested_events(wait);
> +	struct aspeed_xdma_client *client = file->private_data;
> +	struct aspeed_xdma *ctx = client->ctx;
> +
> +	if (req & (EPOLLIN | EPOLLRDNORM)) {
> +		if (client->in_progress)
> +			poll_wait(file, &ctx->wait, wait);
> +
> +		if (!client->in_progress) {
> +			if (client->error)
> +				mask |= EPOLLERR;
> +			else
> +				mask |= EPOLLIN | EPOLLRDNORM;
> +		}
> +	}
> +
> +	if (req & (EPOLLOUT | EPOLLWRNORM)) {
> +		if (ctx->current_client)
> +			poll_wait(file, &ctx->wait, wait);
> +
> +		if (!ctx->current_client)
> +			mask |= EPOLLOUT | EPOLLWRNORM;
> +	}
> +
> +	return mask;
> +}
> +
> +static void aspeed_xdma_vma_close(struct vm_area_struct *vma)
> +{
> +	int rc;
> +	struct aspeed_xdma_client *client = vma->vm_private_data;
> +
> +	rc = wait_event_interruptible(client->ctx->wait, !client->in_progress);
> +	if (rc)
> +		return;
> +
> +	gen_pool_free(client->ctx->pool, (unsigned long)client->virt,
> +		      client->size);
> +
> +	client->virt = NULL;
> +	client->phys = 0;
> +	client->size = 0;
> +}
> +
> +static const struct vm_operations_struct aspeed_xdma_vm_ops = {
> +	.close =	aspeed_xdma_vma_close,
> +};
> +
> +static int aspeed_xdma_mmap(struct file *file, struct vm_area_struct *vma)
> +{
> +	int rc;
> +	struct aspeed_xdma_client *client = file->private_data;
> +	struct aspeed_xdma *ctx = client->ctx;
> +
> +	/* restrict file to one mapping */
> +	if (client->size)
> +		return -EBUSY;
> +
> +	client->size = vma->vm_end - vma->vm_start;
> +	client->virt = gen_pool_dma_alloc(ctx->pool, client->size,
> +					  &client->phys);
> +	if (!client->virt) {
> +		client->phys = 0;
> +		client->size = 0;
> +		return -ENOMEM;
> +	}
> +
> +	vma->vm_pgoff = (client->phys - ctx->mem_phys) >> PAGE_SHIFT;
> +	vma->vm_ops = &aspeed_xdma_vm_ops;
> +	vma->vm_private_data = client;
> +	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
> +
> +	rc = io_remap_pfn_range(vma, vma->vm_start, client->phys >> PAGE_SHIFT,
> +				client->size, vma->vm_page_prot);
> +	if (rc) {

Probably worth a dev_warn() here so we know what happened?

> +		gen_pool_free(ctx->pool, (unsigned long)client->virt,
> +			      client->size);
> +
> +		client->virt = NULL;
> +		client->phys = 0;
> +		client->size = 0;
> +		return rc;
> +	}
> +
> +	dev_dbg(ctx->dev, "mmap: v[%08lx] to p[%08x], s[%08x]\n",
> +		vma->vm_start, (u32)client->phys, client->size);
> +
> +	return 0;
> +}
> +
> +static int aspeed_xdma_open(struct inode *inode, struct file *file)
> +{
> +	struct miscdevice *misc = file->private_data;
> +	struct aspeed_xdma *ctx = container_of(misc, struct aspeed_xdma, misc);
> +	struct aspeed_xdma_client *client = kzalloc(sizeof(*client),
> +						    GFP_KERNEL);
> +
> +	if (!client)
> +		return -ENOMEM;
> +
> +	client->ctx = ctx;
> +	file->private_data = client;
> +	return 0;
> +}
> +
> +static int aspeed_xdma_release(struct inode *inode, struct file *file)
> +{
> +	struct aspeed_xdma_client *client = file->private_data;
> +
> +	kfree(client);

I assume the vma gets torn down before release() gets invoked? I haven't
looked closely.

Andrew

^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v3 05/12] dt-bindings: soc: Add Aspeed XDMA Engine
  2019-12-18 23:12   ` Andrew Jeffery
@ 2019-12-19 15:48     ` Eddie James
  2019-12-19 21:14       ` Andrew Jeffery
  0 siblings, 1 reply; 21+ messages in thread
From: Eddie James @ 2019-12-19 15:48 UTC (permalink / raw)
  To: Andrew Jeffery, linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, Jason Cooper,
	Marc Zyngier, Rob Herring, tglx, Joel Stanley


On 12/18/19 5:12 PM, Andrew Jeffery wrote:
>
> On Thu, 19 Dec 2019, at 01:39, Eddie James wrote:
>> Document the bindings for the Aspeed AST25XX and AST26XX XDMA engine.
>>
>> Signed-off-by: Eddie James <eajames@linux.ibm.com>
>> Reviewed-by: Rob Herring <robh@kernel.org>
>> ---
>> Changes since v2:
>>   - Remove 'sdmc', rename 'vga-mem' to 'memory'
>>
>>   .../devicetree/bindings/soc/aspeed/xdma.txt   | 40 +++++++++++++++++++
>>   MAINTAINERS                                   |  6 +++
>>   2 files changed, 46 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/soc/aspeed/xdma.txt
>>
>> diff --git a/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
>> b/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
>> new file mode 100644
>> index 000000000000..58253ea1587b
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
>> @@ -0,0 +1,40 @@
>> +Aspeed AST25XX and AST26XX XDMA Engine
>> +
>> +The XDMA Engine embedded in the AST2500 and AST2600 SOCs can perform
>> automatic
>> +DMA operations over PCI between the SOC (acting as a BMC) and a host
>> processor.
>> +
>> +Required properties:
>> + - compatible		: must be "aspeed,ast2500-xdma" or
>> +			  "aspeed,ast2600-xdma"
>> + - reg			: contains the address and size of the memory region
>> +			  associated with the XDMA engine registers
>> + - clocks		: clock specifier for the clock associated with the
>> +			  XDMA engine
>> + - resets		: reset specifier for the syscon reset associated with
>> +			  the XDMA engine
>> + - interrupts-extended	: two interrupt cells; the first specifies the
>> global
>> +			  interrupt for the XDMA engine and the second
>> +			  specifies the PCI-E reset or PERST interrupt.
>> + - scu			: a phandle to the syscon node for the system control
>> +			  unit of the SOC
> I think this should be aspeed,scu.


Sure.


>
>> + - memory		: contains the address and size of the memory area to
>> +			  be used by the XDMA engine for DMA operations
> Hmm, I was thinking more like a phandle to a reserved memory region,
> like we have in the aspeed-lpc-ctrl binding.


I think I mentioned before, but that doesn't work with the VGA memory. 
Linux can't reserve it. I haven't quite understood what happens in the 
memory system but I've tried it and it didn't work.


>
>> +
>> +Optional properties:
>> + - pcie-device		: should be either "bmc" or "vga", corresponding to
>> +			  which device should be used by the XDMA engine for
>> +			  DMA operations. If this property is not set, the XDMA
>> +			  engine will use the BMC PCI-E device.
>> +
>> +Example:
>> +
>> +    xdma@1e6e7000 {
>> +        compatible = "aspeed,ast2500-xdma";
>> +        reg = <0x1e6e7000 0x100>;
>> +        clocks = <&syscon ASPEED_CLK_GATE_BCLK>;
>> +        resets = <&syscon ASPEED_RESET_XDMA>;
>> +        interrupts-extended = <&vic 6>, <&scu_ic
>> ASPEED_AST2500_SCU_IC_PCIE_RESET_LO_TO_HI>;
>> +        scu = <&syscon>;
>> +        pcie-device = "bmc";
>> +        memory = <0x9f000000 0x01000000>;
>> +    };
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index ac9c120d192b..8a14d4268bdc 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -2708,6 +2708,12 @@ S:	Maintained
>>   F:	drivers/media/platform/aspeed-video.c
>>   F:	Documentation/devicetree/bindings/media/aspeed-video.txt
>>   
>> +ASPEED XDMA ENGINE DRIVER
>> +M:	Eddie James <eajames@linux.ibm.com>
>> +L:	linux-aspeed@lists.ozlabs.org (moderated for non-subscribers)
>> +S:	Maintained
>> +F:	Documentation/devicetree/bindings/soc/aspeed/xdma.txt
>> +
>>   ASUS NOTEBOOKS AND EEEPC ACPI/WMI EXTRAS DRIVERS
>>   M:	Corentin Chary <corentin.chary@gmail.com>
>>   L:	acpi4asus-user@lists.sourceforge.net
>> -- 
>> 2.24.0
>>
>>

^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v3 07/12] soc: aspeed: xdma: Add user interface
  2019-12-19  1:19   ` Andrew Jeffery
@ 2019-12-19 16:00     ` Eddie James
  2019-12-19 21:16       ` Andrew Jeffery
  0 siblings, 1 reply; 21+ messages in thread
From: Eddie James @ 2019-12-19 16:00 UTC (permalink / raw)
  To: Andrew Jeffery, linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, Jason Cooper,
	Marc Zyngier, Rob Herring, tglx, Joel Stanley


On 12/18/19 7:19 PM, Andrew Jeffery wrote:
>
> On Thu, 19 Dec 2019, at 01:39, Eddie James wrote:
>> This commits adds a miscdevice to provide a user interface to the XDMA
>> engine. The interface provides the write operation to start DMA
>> operations. The DMA parameters are passed as the data to the write call.
>> The actual data to transfer is NOT passed through write. Note that both
>> directions of DMA operation are accomplished through the write command;
>> BMC to host and host to BMC.
>>
>> The XDMA driver reserves an area of physical memory for DMA operations,
>> as the XDMA engine is restricted to accessing certain physical memory
>> areas on some platforms. This memory forms a pool from which users can
>> allocate pages for their usage with calls to mmap. The space allocated
>> by a client will be the space used in the DMA operation. For an
>> "upstream" (BMC to host) operation, the data in the client's area will
>> be transferred to the host. For a "downstream" (host to BMC) operation,
>> the host data will be placed in the client's memory area.
>>
>> Poll is also provided in order to determine when the DMA operation is
>> complete for non-blocking IO.
>>
>> Signed-off-by: Eddie James <eajames@linux.ibm.com>
>> ---
>> Changes since v2:
>>   - Rework commit message to talk about VGA memory less
>>   - Remove user reset functionality
>>   - Clean up sanity checks in aspeed_xdma_write()
>>   - Wait for transfer complete in the vm area close function
>>
>>   drivers/soc/aspeed/aspeed-xdma.c | 205 ++++++++++++++++++++++++++++++-
>>   1 file changed, 203 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/soc/aspeed/aspeed-xdma.c b/drivers/soc/aspeed/aspeed-xdma.c
>> index cb94adf798b1..e844937dc925 100644
>> --- a/drivers/soc/aspeed/aspeed-xdma.c
>> +++ b/drivers/soc/aspeed/aspeed-xdma.c
>> @@ -13,6 +13,7 @@
>>   #include <linux/io.h>
>>   #include <linux/jiffies.h>
>>   #include <linux/mfd/syscon.h>
>> +#include <linux/miscdevice.h>
>>   #include <linux/module.h>
>>   #include <linux/mutex.h>
>>   #include <linux/of_device.h>
>> @@ -201,6 +202,8 @@ struct aspeed_xdma {
>>   	struct clk *clock;
>>   	struct reset_control *reset;
>>   
>> +	/* file_lock serializes reads of current_client */
>> +	struct mutex file_lock;
> I wonder whether start_lock can serve this purpose.
>
>>   	/* client_lock protects error and in_progress of the client */
>>   	spinlock_t client_lock;
>>   	struct aspeed_xdma_client *current_client;
>> @@ -223,6 +226,8 @@ struct aspeed_xdma {
>>   	void __iomem *mem_virt;
>>   	dma_addr_t cmdq_phys;
>>   	struct gen_pool *pool;
>> +
>> +	struct miscdevice misc;
>>   };
>>   
>>   struct aspeed_xdma_client {
>> @@ -522,6 +527,185 @@ static irqreturn_t aspeed_xdma_pcie_irq(int irq,
>> void *arg)
>>   	return IRQ_HANDLED;
>>   }
>>   
>> +static ssize_t aspeed_xdma_write(struct file *file, const char __user *buf,
>> +				 size_t len, loff_t *offset)
>> +{
>> +	int rc;
>> +	struct aspeed_xdma_op op;
>> +	struct aspeed_xdma_client *client = file->private_data;
>> +	struct aspeed_xdma *ctx = client->ctx;
>> +
>> +	if (len != sizeof(op))
>> +		return -EINVAL;
>> +
>> +	rc = copy_from_user(&op, buf, len);
>> +	if (rc)
>> +		return rc;
>> +
>> +	if (!op.len || op.len > client->size ||
>> +	    op.direction > ASPEED_XDMA_DIRECTION_UPSTREAM)
>> +		return -EINVAL;
>> +
>> +	if (file->f_flags & O_NONBLOCK) {
>> +		if (!mutex_trylock(&ctx->file_lock))
>> +			return -EAGAIN;
>> +
>> +		if (ctx->current_client) {
> Should be tested under client_lock for consistency with the previous patch,
> though perhaps you could use READ_ONCE()?


I think READ_ONCE will work.



>
>> +			mutex_unlock(&ctx->file_lock);
>> +			return -EBUSY;
>> +		}
>> +	} else {
>> +		mutex_lock(&ctx->file_lock);
>> +
>> +		rc = wait_event_interruptible(ctx->wait, !ctx->current_client);
>> +		if (rc) {
>> +			mutex_unlock(&ctx->file_lock);
>> +			return -EINTR;
>> +		}
>> +	}
>> +
>> +	aspeed_xdma_start(ctx, &op, client->phys, client);
>> +
>> +	mutex_unlock(&ctx->file_lock);
> Shouldn't we lift start_lock out of aspeed_xdma_start() use that here
> instead of file_lock? I think that would mean that we could remove
> file_lock.


That wouldn't work with the reset though. The reset should hold 
start_lock as well, but if a client is waiting here with start_lock, 
we'd never get to the reset if the transfer doesn't complete. I think 
file_lock is necessary.


>
>> +
>> +	if (!(file->f_flags & O_NONBLOCK)) {
>> +		rc = wait_event_interruptible(ctx->wait, !client->in_progress);
>> +		if (rc)
>> +			return -EINTR;
>> +
>> +		if (client->error)
>> +			return -EIO;
>> +	}
>> +
>> +	return len;
>> +}
>> +
>> +static __poll_t aspeed_xdma_poll(struct file *file,
>> +				 struct poll_table_struct *wait)
>> +{
>> +	__poll_t mask = 0;
>> +	__poll_t req = poll_requested_events(wait);
>> +	struct aspeed_xdma_client *client = file->private_data;
>> +	struct aspeed_xdma *ctx = client->ctx;
>> +
>> +	if (req & (EPOLLIN | EPOLLRDNORM)) {
>> +		if (client->in_progress)
>> +			poll_wait(file, &ctx->wait, wait);
>> +
>> +		if (!client->in_progress) {
>> +			if (client->error)
>> +				mask |= EPOLLERR;
>> +			else
>> +				mask |= EPOLLIN | EPOLLRDNORM;
>> +		}
>> +	}
>> +
>> +	if (req & (EPOLLOUT | EPOLLWRNORM)) {
>> +		if (ctx->current_client)
>> +			poll_wait(file, &ctx->wait, wait);
>> +
>> +		if (!ctx->current_client)
>> +			mask |= EPOLLOUT | EPOLLWRNORM;
>> +	}
>> +
>> +	return mask;
>> +}
>> +
>> +static void aspeed_xdma_vma_close(struct vm_area_struct *vma)
>> +{
>> +	int rc;
>> +	struct aspeed_xdma_client *client = vma->vm_private_data;
>> +
>> +	rc = wait_event_interruptible(client->ctx->wait, !client->in_progress);
>> +	if (rc)
>> +		return;
>> +
>> +	gen_pool_free(client->ctx->pool, (unsigned long)client->virt,
>> +		      client->size);
>> +
>> +	client->virt = NULL;
>> +	client->phys = 0;
>> +	client->size = 0;
>> +}
>> +
>> +static const struct vm_operations_struct aspeed_xdma_vm_ops = {
>> +	.close =	aspeed_xdma_vma_close,
>> +};
>> +
>> +static int aspeed_xdma_mmap(struct file *file, struct vm_area_struct *vma)
>> +{
>> +	int rc;
>> +	struct aspeed_xdma_client *client = file->private_data;
>> +	struct aspeed_xdma *ctx = client->ctx;
>> +
>> +	/* restrict file to one mapping */
>> +	if (client->size)
>> +		return -EBUSY;
>> +
>> +	client->size = vma->vm_end - vma->vm_start;
>> +	client->virt = gen_pool_dma_alloc(ctx->pool, client->size,
>> +					  &client->phys);
>> +	if (!client->virt) {
>> +		client->phys = 0;
>> +		client->size = 0;
>> +		return -ENOMEM;
>> +	}
>> +
>> +	vma->vm_pgoff = (client->phys - ctx->mem_phys) >> PAGE_SHIFT;
>> +	vma->vm_ops = &aspeed_xdma_vm_ops;
>> +	vma->vm_private_data = client;
>> +	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
>> +
>> +	rc = io_remap_pfn_range(vma, vma->vm_start, client->phys >> PAGE_SHIFT,
>> +				client->size, vma->vm_page_prot);
>> +	if (rc) {
> Probably worth a dev_warn() here so we know what happened?


Sure.


>
>> +		gen_pool_free(ctx->pool, (unsigned long)client->virt,
>> +			      client->size);
>> +
>> +		client->virt = NULL;
>> +		client->phys = 0;
>> +		client->size = 0;
>> +		return rc;
>> +	}
>> +
>> +	dev_dbg(ctx->dev, "mmap: v[%08lx] to p[%08x], s[%08x]\n",
>> +		vma->vm_start, (u32)client->phys, client->size);
>> +
>> +	return 0;
>> +}
>> +
>> +static int aspeed_xdma_open(struct inode *inode, struct file *file)
>> +{
>> +	struct miscdevice *misc = file->private_data;
>> +	struct aspeed_xdma *ctx = container_of(misc, struct aspeed_xdma, misc);
>> +	struct aspeed_xdma_client *client = kzalloc(sizeof(*client),
>> +						    GFP_KERNEL);
>> +
>> +	if (!client)
>> +		return -ENOMEM;
>> +
>> +	client->ctx = ctx;
>> +	file->private_data = client;
>> +	return 0;
>> +}
>> +
>> +static int aspeed_xdma_release(struct inode *inode, struct file *file)
>> +{
>> +	struct aspeed_xdma_client *client = file->private_data;
>> +
>> +	kfree(client);
> I assume the vma gets torn down before release() gets invoked? I haven't
> looked closely.


 From what I've read, yes, the VMA has to be closed before release() can 
be called.


Thanks for the review!

Eddie


>
> Andrew

^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v3 05/12] dt-bindings: soc: Add Aspeed XDMA Engine
  2019-12-19 15:48     ` Eddie James
@ 2019-12-19 21:14       ` Andrew Jeffery
  0 siblings, 0 replies; 21+ messages in thread
From: Andrew Jeffery @ 2019-12-19 21:14 UTC (permalink / raw)
  To: Eddie James, linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, Jason Cooper,
	Marc Zyngier, Rob Herring, tglx, Joel Stanley



On Fri, 20 Dec 2019, at 02:18, Eddie James wrote:
> 
> On 12/18/19 5:12 PM, Andrew Jeffery wrote:
> >
> > On Thu, 19 Dec 2019, at 01:39, Eddie James wrote:
> >> Document the bindings for the Aspeed AST25XX and AST26XX XDMA engine.
> >>
> >> Signed-off-by: Eddie James <eajames@linux.ibm.com>
> >> Reviewed-by: Rob Herring <robh@kernel.org>
> >> ---
> >> Changes since v2:
> >>   - Remove 'sdmc', rename 'vga-mem' to 'memory'
> >>
> >>   .../devicetree/bindings/soc/aspeed/xdma.txt   | 40 +++++++++++++++++++
> >>   MAINTAINERS                                   |  6 +++
> >>   2 files changed, 46 insertions(+)
> >>   create mode 100644 Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> >>
> >> diff --git a/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> >> b/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> >> new file mode 100644
> >> index 000000000000..58253ea1587b
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/soc/aspeed/xdma.txt
> >> @@ -0,0 +1,40 @@
> >> +Aspeed AST25XX and AST26XX XDMA Engine
> >> +
> >> +The XDMA Engine embedded in the AST2500 and AST2600 SOCs can perform
> >> automatic
> >> +DMA operations over PCI between the SOC (acting as a BMC) and a host
> >> processor.
> >> +
> >> +Required properties:
> >> + - compatible		: must be "aspeed,ast2500-xdma" or
> >> +			  "aspeed,ast2600-xdma"
> >> + - reg			: contains the address and size of the memory region
> >> +			  associated with the XDMA engine registers
> >> + - clocks		: clock specifier for the clock associated with the
> >> +			  XDMA engine
> >> + - resets		: reset specifier for the syscon reset associated with
> >> +			  the XDMA engine
> >> + - interrupts-extended	: two interrupt cells; the first specifies the
> >> global
> >> +			  interrupt for the XDMA engine and the second
> >> +			  specifies the PCI-E reset or PERST interrupt.
> >> + - scu			: a phandle to the syscon node for the system control
> >> +			  unit of the SOC
> > I think this should be aspeed,scu.
> 
> 
> Sure.
> 
> 
> >
> >> + - memory		: contains the address and size of the memory area to
> >> +			  be used by the XDMA engine for DMA operations
> > Hmm, I was thinking more like a phandle to a reserved memory region,
> > like we have in the aspeed-lpc-ctrl binding.
> 
> 
> I think I mentioned before, but that doesn't work with the VGA memory. 
> Linux can't reserve it. I haven't quite understood what happens in the 
> memory system but I've tried it and it didn't work.
> 

Yeah, I think you have mentioned that before, sorry for the noise.

Andrew

^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v3 07/12] soc: aspeed: xdma: Add user interface
  2019-12-19 16:00     ` Eddie James
@ 2019-12-19 21:16       ` Andrew Jeffery
  0 siblings, 0 replies; 21+ messages in thread
From: Andrew Jeffery @ 2019-12-19 21:16 UTC (permalink / raw)
  To: Eddie James, linux-aspeed
  Cc: linux-kernel, devicetree, mark.rutland, Jason Cooper,
	Marc Zyngier, Rob Herring, tglx, Joel Stanley



On Fri, 20 Dec 2019, at 02:30, Eddie James wrote:
> 
> On 12/18/19 7:19 PM, Andrew Jeffery wrote:
> >
> > On Thu, 19 Dec 2019, at 01:39, Eddie James wrote:
> >> +			mutex_unlock(&ctx->file_lock);
> >> +			return -EBUSY;
> >> +		}
> >> +	} else {
> >> +		mutex_lock(&ctx->file_lock);
> >> +
> >> +		rc = wait_event_interruptible(ctx->wait, !ctx->current_client);
> >> +		if (rc) {
> >> +			mutex_unlock(&ctx->file_lock);
> >> +			return -EINTR;
> >> +		}
> >> +	}
> >> +
> >> +	aspeed_xdma_start(ctx, &op, client->phys, client);
> >> +
> >> +	mutex_unlock(&ctx->file_lock);
> > Shouldn't we lift start_lock out of aspeed_xdma_start() use that here
> > instead of file_lock? I think that would mean that we could remove
> > file_lock.
> 
> 
> That wouldn't work with the reset though. The reset should hold 
> start_lock as well, but if a client is waiting here with start_lock, 
> we'd never get to the reset if the transfer doesn't complete. I think 
> file_lock is necessary.

Hmm, let me think about this some more.

Andrew

^ permalink raw reply	[flat|nested] 21+ messages in thread

end of thread, other threads:[~2019-12-19 21:14 UTC | newest]

Thread overview: 21+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-12-18 15:09 [PATCH v3 00/12] aspeed: Add SCU interrupt controller and XDMA engine drivers Eddie James
2019-12-18 15:09 ` [PATCH v3 01/12] dt-bindings: interrupt-controller: Add Aspeed SCU interrupt controller Eddie James
2019-12-18 15:09 ` [PATCH v3 02/12] irqchip: " Eddie James
2019-12-18 15:09 ` [PATCH v3 03/12] ARM: dts: aspeed: ast2500: Add " Eddie James
2019-12-18 22:34   ` Andrew Jeffery
2019-12-18 15:09 ` [PATCH v3 04/12] ARM: dts: aspeed: ast2600: Add SCU interrupt controllers Eddie James
2019-12-18 15:09 ` [PATCH v3 05/12] dt-bindings: soc: Add Aspeed XDMA Engine Eddie James
2019-12-18 23:12   ` Andrew Jeffery
2019-12-19 15:48     ` Eddie James
2019-12-19 21:14       ` Andrew Jeffery
2019-12-18 15:09 ` [PATCH v3 06/12] soc: aspeed: Add XDMA Engine Driver Eddie James
2019-12-18 23:12   ` Andrew Jeffery
2019-12-18 15:09 ` [PATCH v3 07/12] soc: aspeed: xdma: Add user interface Eddie James
2019-12-19  1:19   ` Andrew Jeffery
2019-12-19 16:00     ` Eddie James
2019-12-19 21:16       ` Andrew Jeffery
2019-12-18 15:09 ` [PATCH v3 08/12] soc: aspeed: xdma: Add reset ioctl Eddie James
2019-12-18 15:09 ` [PATCH v3 09/12] ARM: dts: aspeed: ast2500: Add XDMA Engine Eddie James
2019-12-18 15:09 ` [PATCH v3 10/12] ARM: dts: aspeed: ast2600: " Eddie James
2019-12-18 15:09 ` [PATCH v3 11/12] ARM: dts: aspeed: witherspoon: Enable " Eddie James
2019-12-18 15:09 ` [PATCH v3 12/12] ARM: dts: aspeed: tacoma: Enable XDMA engine Eddie James

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