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* [PATCH RESEND V9 0/6] Add generic syscon reboot driver
@ 2014-09-30 23:25 Feng Kan
  2014-09-30 23:25 ` [PATCH RESEND V9 1/6] power: reset: Add generic SYSCON register mapped reset Feng Kan
                   ` (5 more replies)
  0 siblings, 6 replies; 9+ messages in thread
From: Feng Kan @ 2014-09-30 23:25 UTC (permalink / raw)
  To: linux-arm-kernel

Enable reboot driver for the X-Gene platform. Add generic syscon reboot
driver. Replace X-Gene reboot driver with the generic syscon reboot
driver.

V9 Change:
        - rebase on Guenter Roeck's reset handler patch set now in linux next.
	  This allows for a generic reset to be call rather than the arm
          specific reset handler.

V8 Change:
        - change Kconfig to depend on ARM || ARM64 || COMPILE_TEST

V7 Change:
        - Seem V3 on, the patches were not making in to the mailinglist.
        - Fix build error produced by other ARCH while including this
          driver. Set to depend on arm64 ARCH for now.

V6 Change:
        - Add documentation for scu node.

V5 Change:
        - Documentation update, endian and access size.

V4 Change:
        - Remove old X-Gene reboot driver
        - Add generic syscon reboot driver
        - Add DTS and Kconfig for X-Gene reboot using syscon method

V3 Change:
        - Remove the reboot driver's use of acpi resource patch.
        - Change the reboot driver to use syscon to parse out
          system clock register. Remove the old method of getting
          register from the reboot driver directly.
        - Remove documentation since its now simple.

V2 Change:
        - Add support for using ACPI resource.


Feng Kan (6):
  power: reset: Add generic SYSCON register mapped reset
  Documentation: power: reset: Add documentation for generic SYSCON
    reboot driver
  Documentation: arm64: add SCU dts binding documentation to linux
    kernel
  arm64: dts: Add X-Gene reboot driver dts node
  arm64: Select reboot driver for X-Gene platform
  power: reset: Remove X-Gene reboot driver

 Documentation/devicetree/bindings/arm/apm/scu.txt  |  17 ++++
 .../bindings/power/reset/syscon-reboot.txt         |  23 +++++
 arch/arm64/Kconfig                                 |   2 +
 arch/arm64/boot/dts/apm-storm.dtsi                 |  11 +++
 drivers/power/reset/Kconfig                        |  11 +--
 drivers/power/reset/Makefile                       |   2 +-
 drivers/power/reset/syscon-reboot.c                |  96 +++++++++++++++++++
 drivers/power/reset/xgene-reboot.c                 | 103 ---------------------
 8 files changed, 155 insertions(+), 110 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/arm/apm/scu.txt
 create mode 100644 Documentation/devicetree/bindings/power/reset/syscon-reboot.txt
 create mode 100644 drivers/power/reset/syscon-reboot.c
 delete mode 100644 drivers/power/reset/xgene-reboot.c

-- 
1.9.1

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH RESEND V9 1/6] power: reset: Add generic SYSCON register mapped reset
  2014-09-30 23:25 [PATCH RESEND V9 0/6] Add generic syscon reboot driver Feng Kan
@ 2014-09-30 23:25 ` Feng Kan
  2014-10-01  3:11   ` Guenter Roeck
  2014-10-01 15:18   ` Sebastian Reichel
  2014-09-30 23:25 ` [PATCH RESEND V9 2/6] Documentation: power: reset: Add documentation for generic SYSCON reboot driver Feng Kan
                   ` (4 subsequent siblings)
  5 siblings, 2 replies; 9+ messages in thread
From: Feng Kan @ 2014-09-30 23:25 UTC (permalink / raw)
  To: linux-arm-kernel

Add a generic SYSCON register mapped reset mechanism.

Signed-off-by: Feng Kan <fkan@apm.com>
---
 drivers/power/reset/Kconfig         |  5 ++
 drivers/power/reset/Makefile        |  1 +
 drivers/power/reset/syscon-reboot.c | 96 +++++++++++++++++++++++++++++++++++++
 3 files changed, 102 insertions(+)
 create mode 100644 drivers/power/reset/syscon-reboot.c

diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 1915dde..a863fa1 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -143,4 +143,9 @@ config POWER_RESET_KEYSTONE
 	help
 	  Reboot support for the KEYSTONE SoCs.
 
+config POWER_RESET_SYSCON
+	bool "Generic SYSCON regmap reset driver"
+	depends on POWER_RESET && MFD_SYSCON && OF
+	help
+	  Reboot support for generic SYSCON mapped register reset.
 endif
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 01e401d..76ce1c5 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -16,3 +16,4 @@ obj-$(CONFIG_POWER_RESET_VERSATILE) += arm-versatile-reboot.o
 obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o
 obj-$(CONFIG_POWER_RESET_XGENE) += xgene-reboot.o
 obj-$(CONFIG_POWER_RESET_KEYSTONE) += keystone-reset.o
+obj-$(CONFIG_POWER_RESET_SYSCON) += syscon-reboot.o
diff --git a/drivers/power/reset/syscon-reboot.c b/drivers/power/reset/syscon-reboot.c
new file mode 100644
index 0000000..948e0ee
--- /dev/null
+++ b/drivers/power/reset/syscon-reboot.c
@@ -0,0 +1,96 @@
+/*
+ * Generic Syscon Reboot Driver
+ *
+ * Copyright (c) 2013, Applied Micro Circuits Corporation
+ * Author: Feng Kan <fkan@apm.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#include <linux/io.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/notifier.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/reboot.h>
+
+struct syscon_reboot_context {
+	struct regmap *map;
+	u32 offset;
+	u32 mask;
+	struct notifier_block restart_handler;
+};
+
+static struct syscon_reboot_context *syscon_reboot_ctx;
+
+static int syscon_restart_handle(struct notifier_block *this,
+					unsigned long mode, void *cmd)
+{
+	struct syscon_reboot_context *ctx = syscon_reboot_ctx;
+	unsigned long timeout;
+
+	/* Issue the reboot */
+	if (ctx->map)
+		regmap_write(ctx->map, ctx->offset, ctx->mask);
+
+	timeout = jiffies + HZ;
+	while (time_before(jiffies, timeout))
+		cpu_relax();
+
+	pr_emerg("Unable to restart system\n");
+	return NOTIFY_DONE;
+}
+
+static int syscon_reboot_probe(struct platform_device *pdev)
+{
+	struct syscon_reboot_context *ctx;
+	struct device *dev = &pdev->dev;
+	int err;
+
+	ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->map = syscon_regmap_lookup_by_phandle(dev->of_node, "regmap");
+	if (IS_ERR(ctx->map))
+		return PTR_ERR(ctx->map);
+
+	if (of_property_read_u32(pdev->dev.of_node, "offset", &ctx->offset))
+		return -EINVAL;
+
+	if (of_property_read_u32(pdev->dev.of_node, "mask", &ctx->mask))
+		return -EINVAL;
+
+	ctx->restart_handler.notifier_call = syscon_restart_handle;
+	ctx->restart_handler.priority = 128;
+	err = register_restart_handler(&ctx->restart_handler);
+	if (err)
+		dev_err(dev, "can't register restart notifier (err=%d)\n", err);
+
+	syscon_reboot_ctx = ctx;
+
+	return 0;
+}
+
+static struct of_device_id syscon_reboot_of_match[] = {
+	{ .compatible = "syscon-reboot" },
+	{}
+};
+
+static struct platform_driver syscon_reboot_driver = {
+	.probe = syscon_reboot_probe,
+	.driver = {
+		.name = "syscon-reboot",
+		.of_match_table = syscon_reboot_of_match,
+	},
+};
+module_platform_driver(syscon_reboot_driver);
-- 
1.9.1

^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH RESEND V9 2/6] Documentation: power: reset: Add documentation for generic SYSCON reboot driver
  2014-09-30 23:25 [PATCH RESEND V9 0/6] Add generic syscon reboot driver Feng Kan
  2014-09-30 23:25 ` [PATCH RESEND V9 1/6] power: reset: Add generic SYSCON register mapped reset Feng Kan
@ 2014-09-30 23:25 ` Feng Kan
  2014-09-30 23:25 ` [PATCH RESEND V9 3/6] Documentation: arm64: add SCU dts binding documentation to linux kernel Feng Kan
                   ` (3 subsequent siblings)
  5 siblings, 0 replies; 9+ messages in thread
From: Feng Kan @ 2014-09-30 23:25 UTC (permalink / raw)
  To: linux-arm-kernel

Add documentation for generic SYSCON reboot driver.

Signed-off-by: Feng Kan <fkan@apm.com>
---
 .../bindings/power/reset/syscon-reboot.txt         | 23 ++++++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/power/reset/syscon-reboot.txt

diff --git a/Documentation/devicetree/bindings/power/reset/syscon-reboot.txt b/Documentation/devicetree/bindings/power/reset/syscon-reboot.txt
new file mode 100644
index 0000000..1190631
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/reset/syscon-reboot.txt
@@ -0,0 +1,23 @@
+Generic SYSCON mapped register reset driver
+
+This is a generic reset driver using syscon to map the reset register.
+The reset is generally performed with a write to the reset register
+defined by the register map pointed by syscon reference plus the offset
+with the mask defined in the reboot node.
+
+Required properties:
+- compatible: should contain "syscon-reboot"
+- regmap: this is phandle to the register map node
+- offset: offset in the register map for the reboot register (in bytes)
+- mask: the reset value written to the reboot register (32 bit access)
+
+Default will be little endian mode, 32 bit access only.
+
+Examples:
+
+	reboot {
+	   compatible = "syscon-reboot";
+	   regmap = <&regmapnode>;
+	   offset = <0x0>;
+	   mask = <0x1>;
+	};
-- 
1.9.1

^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH RESEND V9 3/6] Documentation: arm64: add SCU dts binding documentation to linux kernel
  2014-09-30 23:25 [PATCH RESEND V9 0/6] Add generic syscon reboot driver Feng Kan
  2014-09-30 23:25 ` [PATCH RESEND V9 1/6] power: reset: Add generic SYSCON register mapped reset Feng Kan
  2014-09-30 23:25 ` [PATCH RESEND V9 2/6] Documentation: power: reset: Add documentation for generic SYSCON reboot driver Feng Kan
@ 2014-09-30 23:25 ` Feng Kan
  2014-09-30 23:25 ` [PATCH RESEND V9 4/6] arm64: dts: Add X-Gene reboot driver dts node Feng Kan
                   ` (2 subsequent siblings)
  5 siblings, 0 replies; 9+ messages in thread
From: Feng Kan @ 2014-09-30 23:25 UTC (permalink / raw)
  To: linux-arm-kernel

This add documentation for the SCU system clock unit device tree binding
to the kernel.

Signed-off-by: Feng Kan <fkan@apm.com>
---
 Documentation/devicetree/bindings/arm/apm/scu.txt | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/arm/apm/scu.txt

diff --git a/Documentation/devicetree/bindings/arm/apm/scu.txt b/Documentation/devicetree/bindings/arm/apm/scu.txt
new file mode 100644
index 0000000..b45be06
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/apm/scu.txt
@@ -0,0 +1,17 @@
+APM X-GENE SoC series SCU Registers
+
+This system clock unit contain various register that control block resets,
+clock enable/disables, clock divisors and other deepsleep registers.
+
+Properties:
+ - compatible : should contain two values. First value must be:
+		   - "apm,xgene-scu"
+		second value must be always "syscon".
+
+ - reg : offset and length of the register set.
+
+Example :
+	scu: system-clk-controller at 17000000 {
+		compatible = "apm,xgene-scu","syscon";
+		reg = <0x0 0x17000000 0x0 0x400>;
+	};
-- 
1.9.1

^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH RESEND V9 4/6] arm64: dts: Add X-Gene reboot driver dts node
  2014-09-30 23:25 [PATCH RESEND V9 0/6] Add generic syscon reboot driver Feng Kan
                   ` (2 preceding siblings ...)
  2014-09-30 23:25 ` [PATCH RESEND V9 3/6] Documentation: arm64: add SCU dts binding documentation to linux kernel Feng Kan
@ 2014-09-30 23:25 ` Feng Kan
  2014-09-30 23:25 ` [PATCH RESEND V9 5/6] arm64: Select reboot driver for X-Gene platform Feng Kan
  2014-09-30 23:25 ` [PATCH RESEND V9 6/6] power: reset: Remove X-Gene reboot driver Feng Kan
  5 siblings, 0 replies; 9+ messages in thread
From: Feng Kan @ 2014-09-30 23:25 UTC (permalink / raw)
  To: linux-arm-kernel

Add X-Gene platform reboot driver dts node.

Signed-off-by: Feng Kan <fkan@apm.com>
---
 arch/arm64/boot/dts/apm-storm.dtsi | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/arm64/boot/dts/apm-storm.dtsi b/arch/arm64/boot/dts/apm-storm.dtsi
index f391972..cfde5f8 100644
--- a/arch/arm64/boot/dts/apm-storm.dtsi
+++ b/arch/arm64/boot/dts/apm-storm.dtsi
@@ -103,6 +103,11 @@
 		#size-cells = <2>;
 		ranges;
 
+		scu: system-clk-controller at 17000000 {
+			compatible = "apm,xgene-scu","syscon";
+			reg = <0x0 0x17000000 0x0 0x400>;
+		};
+
 		clocks {
 			#address-cells = <2>;
 			#size-cells = <2>;
@@ -442,5 +447,11 @@
 			clocks = <&rngpkaclk 0>;
 		};
 
+		reboot: reboot at 17000014 {
+			compatible = "syscon-reboot";
+			regmap = <&scu>;
+			offset = <0x14>;
+			mask = <0x1>;
+		};
 	};
 };
-- 
1.9.1

^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH RESEND V9 5/6] arm64: Select reboot driver for X-Gene platform
  2014-09-30 23:25 [PATCH RESEND V9 0/6] Add generic syscon reboot driver Feng Kan
                   ` (3 preceding siblings ...)
  2014-09-30 23:25 ` [PATCH RESEND V9 4/6] arm64: dts: Add X-Gene reboot driver dts node Feng Kan
@ 2014-09-30 23:25 ` Feng Kan
  2014-09-30 23:25 ` [PATCH RESEND V9 6/6] power: reset: Remove X-Gene reboot driver Feng Kan
  5 siblings, 0 replies; 9+ messages in thread
From: Feng Kan @ 2014-09-30 23:25 UTC (permalink / raw)
  To: linux-arm-kernel

Select reboot driver for X-Gene platform.

Signed-off-by: Feng Kan <fkan@apm.com>
---
 arch/arm64/Kconfig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 2ca2ebd..2edccbc 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -149,6 +149,8 @@ config ARCH_VEXPRESS
 
 config ARCH_XGENE
 	bool "AppliedMicro X-Gene SOC Family"
+	select MFD_SYSCON
+	select POWER_RESET_SYSCON
 	help
 	  This enables support for AppliedMicro X-Gene SOC Family
 
-- 
1.9.1

^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH RESEND V9 6/6] power: reset: Remove X-Gene reboot driver
  2014-09-30 23:25 [PATCH RESEND V9 0/6] Add generic syscon reboot driver Feng Kan
                   ` (4 preceding siblings ...)
  2014-09-30 23:25 ` [PATCH RESEND V9 5/6] arm64: Select reboot driver for X-Gene platform Feng Kan
@ 2014-09-30 23:25 ` Feng Kan
  5 siblings, 0 replies; 9+ messages in thread
From: Feng Kan @ 2014-09-30 23:25 UTC (permalink / raw)
  To: linux-arm-kernel

Remove X-Gene reboot driver.

Signed-off-by: Feng Kan <fkan@apm.com>
Signed-off-by: Loc Ho <lho@apm.com>
---
 drivers/power/reset/Kconfig        |   6 ---
 drivers/power/reset/Makefile       |   1 -
 drivers/power/reset/xgene-reboot.c | 103 -------------------------------------
 3 files changed, 110 deletions(-)
 delete mode 100644 drivers/power/reset/xgene-reboot.c

diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index a863fa1..98f9086 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -130,12 +130,6 @@ config POWER_RESET_VEXPRESS
 	  Power off and reset support for the ARM Ltd. Versatile
 	  Express boards.
 
-config POWER_RESET_XGENE
-	bool "APM SoC X-Gene reset driver"
-	depends on ARM64
-	help
-	  Reboot support for the APM SoC X-Gene Eval boards.
-
 config POWER_RESET_KEYSTONE
 	bool "Keystone reset driver"
 	depends on ARCH_KEYSTONE
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 76ce1c5..e6cda42 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -14,6 +14,5 @@ obj-$(CONFIG_POWER_RESET_SUN6I) += sun6i-reboot.o
 obj-$(CONFIG_POWER_RESET_ST) += st-poweroff.o
 obj-$(CONFIG_POWER_RESET_VERSATILE) += arm-versatile-reboot.o
 obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o
-obj-$(CONFIG_POWER_RESET_XGENE) += xgene-reboot.o
 obj-$(CONFIG_POWER_RESET_KEYSTONE) += keystone-reset.o
 obj-$(CONFIG_POWER_RESET_SYSCON) += syscon-reboot.o
diff --git a/drivers/power/reset/xgene-reboot.c b/drivers/power/reset/xgene-reboot.c
deleted file mode 100644
index 6b49be6..0000000
--- a/drivers/power/reset/xgene-reboot.c
+++ /dev/null
@@ -1,103 +0,0 @@
-/*
- * AppliedMicro X-Gene SoC Reboot Driver
- *
- * Copyright (c) 2013, Applied Micro Circuits Corporation
- * Author: Feng Kan <fkan@apm.com>
- * Author: Loc Ho <lho@apm.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- * MA 02111-1307 USA
- *
- * This driver provides system reboot functionality for APM X-Gene SoC.
- * For system shutdown, this is board specify. If a board designer
- * implements GPIO shutdown, use the gpio-poweroff.c driver.
- */
-#include <linux/io.h>
-#include <linux/of_device.h>
-#include <linux/of_address.h>
-#include <linux/platform_device.h>
-#include <linux/stat.h>
-#include <linux/slab.h>
-#include <asm/system_misc.h>
-
-struct xgene_reboot_context {
-	struct platform_device *pdev;
-	void *csr;
-	u32 mask;
-};
-
-static struct xgene_reboot_context *xgene_restart_ctx;
-
-static void xgene_restart(enum reboot_mode mode, const char *cmd)
-{
-	struct xgene_reboot_context *ctx = xgene_restart_ctx;
-	unsigned long timeout;
-
-	/* Issue the reboot */
-	if (ctx)
-		writel(ctx->mask, ctx->csr);
-
-	timeout = jiffies + HZ;
-	while (time_before(jiffies, timeout))
-		cpu_relax();
-
-	dev_emerg(&ctx->pdev->dev, "Unable to restart system\n");
-}
-
-static int xgene_reboot_probe(struct platform_device *pdev)
-{
-	struct xgene_reboot_context *ctx;
-
-	ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
-	if (!ctx) {
-		dev_err(&pdev->dev, "out of memory for context\n");
-		return -ENODEV;
-	}
-
-	ctx->csr = of_iomap(pdev->dev.of_node, 0);
-	if (!ctx->csr) {
-		devm_kfree(&pdev->dev, ctx);
-		dev_err(&pdev->dev, "can not map resource\n");
-		return -ENODEV;
-	}
-
-	if (of_property_read_u32(pdev->dev.of_node, "mask", &ctx->mask))
-		ctx->mask = 0xFFFFFFFF;
-
-	ctx->pdev = pdev;
-	arm_pm_restart = xgene_restart;
-	xgene_restart_ctx = ctx;
-
-	return 0;
-}
-
-static struct of_device_id xgene_reboot_of_match[] = {
-	{ .compatible = "apm,xgene-reboot" },
-	{}
-};
-
-static struct platform_driver xgene_reboot_driver = {
-	.probe = xgene_reboot_probe,
-	.driver = {
-		.name = "xgene-reboot",
-		.of_match_table = xgene_reboot_of_match,
-	},
-};
-
-static int __init xgene_reboot_init(void)
-{
-	return platform_driver_register(&xgene_reboot_driver);
-}
-device_initcall(xgene_reboot_init);
-- 
1.9.1

^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH RESEND V9 1/6] power: reset: Add generic SYSCON register mapped reset
  2014-09-30 23:25 ` [PATCH RESEND V9 1/6] power: reset: Add generic SYSCON register mapped reset Feng Kan
@ 2014-10-01  3:11   ` Guenter Roeck
  2014-10-01 15:18   ` Sebastian Reichel
  1 sibling, 0 replies; 9+ messages in thread
From: Guenter Roeck @ 2014-10-01  3:11 UTC (permalink / raw)
  To: linux-arm-kernel

On 09/30/2014 04:25 PM, Feng Kan wrote:
> Add a generic SYSCON register mapped reset mechanism.
>
> Signed-off-by: Feng Kan <fkan@apm.com>
> ---
>   drivers/power/reset/Kconfig         |  5 ++
>   drivers/power/reset/Makefile        |  1 +
>   drivers/power/reset/syscon-reboot.c | 96 +++++++++++++++++++++++++++++++++++++
>   3 files changed, 102 insertions(+)
>   create mode 100644 drivers/power/reset/syscon-reboot.c
>
> diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
> index 1915dde..a863fa1 100644
> --- a/drivers/power/reset/Kconfig
> +++ b/drivers/power/reset/Kconfig
> @@ -143,4 +143,9 @@ config POWER_RESET_KEYSTONE
>   	help
>   	  Reboot support for the KEYSTONE SoCs.
>
> +config POWER_RESET_SYSCON
> +	bool "Generic SYSCON regmap reset driver"
> +	depends on POWER_RESET && MFD_SYSCON && OF

Other drivers have
	select MFD_SYSCON

> +	help
> +	  Reboot support for generic SYSCON mapped register reset.
>   endif
> diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
> index 01e401d..76ce1c5 100644
> --- a/drivers/power/reset/Makefile
> +++ b/drivers/power/reset/Makefile
> @@ -16,3 +16,4 @@ obj-$(CONFIG_POWER_RESET_VERSATILE) += arm-versatile-reboot.o
>   obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o
>   obj-$(CONFIG_POWER_RESET_XGENE) += xgene-reboot.o
>   obj-$(CONFIG_POWER_RESET_KEYSTONE) += keystone-reset.o
> +obj-$(CONFIG_POWER_RESET_SYSCON) += syscon-reboot.o
> diff --git a/drivers/power/reset/syscon-reboot.c b/drivers/power/reset/syscon-reboot.c
> new file mode 100644
> index 0000000..948e0ee
> --- /dev/null
> +++ b/drivers/power/reset/syscon-reboot.c
> @@ -0,0 +1,96 @@
> +/*
> + * Generic Syscon Reboot Driver
> + *
> + * Copyright (c) 2013, Applied Micro Circuits Corporation
> + * Author: Feng Kan <fkan@apm.com>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation; either version 2 of
> + * the License, or (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +#include <linux/io.h>
> +#include <linux/of_device.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
> +#include <linux/notifier.h>

alphabetic order of include files ?

> +#include <linux/mfd/syscon.h>
> +#include <linux/regmap.h>
> +#include <linux/reboot.h>
> +
> +struct syscon_reboot_context {
> +	struct regmap *map;
> +	u32 offset;
> +	u32 mask;
> +	struct notifier_block restart_handler;
> +};
> +
> +static struct syscon_reboot_context *syscon_reboot_ctx;
> +
> +static int syscon_restart_handle(struct notifier_block *this,
> +					unsigned long mode, void *cmd)
> +{
> +	struct syscon_reboot_context *ctx = syscon_reboot_ctx;

Since restart_handler is part of syscon_reboot_context, you
do not need a static variable. You can use
	struct syscon_reboot_context *ctx = container_of(ctx, struct syscon_reboot_context, restart_handler);
instead.

> +	unsigned long timeout;
> +
> +	/* Issue the reboot */
> +	if (ctx->map)
> +		regmap_write(ctx->map, ctx->offset, ctx->mask);
> +
The check for ctx->map is not needed. If the restart handler is installed,
it will always be valid.

> +	timeout = jiffies + HZ;
> +	while (time_before(jiffies, timeout))
> +		cpu_relax();
> +
jiffies won't work here, and nothing else is expected to happen.
Just use mdelay(1000);

> +	pr_emerg("Unable to restart system\n");
> +	return NOTIFY_DONE;
> +}
> +
> +static int syscon_reboot_probe(struct platform_device *pdev)
> +{
> +	struct syscon_reboot_context *ctx;
> +	struct device *dev = &pdev->dev;
> +	int err;
> +
> +	ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
> +	if (!ctx)
> +		return -ENOMEM;
> +
> +	ctx->map = syscon_regmap_lookup_by_phandle(dev->of_node, "regmap");
> +	if (IS_ERR(ctx->map))
> +		return PTR_ERR(ctx->map);
> +
> +	if (of_property_read_u32(pdev->dev.of_node, "offset", &ctx->offset))
> +		return -EINVAL;
> +
> +	if (of_property_read_u32(pdev->dev.of_node, "mask", &ctx->mask))
> +		return -EINVAL;
> +
> +	ctx->restart_handler.notifier_call = syscon_restart_handle;
> +	ctx->restart_handler.priority = 128;
> +	err = register_restart_handler(&ctx->restart_handler);
> +	if (err)
> +		dev_err(dev, "can't register restart notifier (err=%d)\n", err);
> +
> +	syscon_reboot_ctx = ctx;
> +
> +	return 0;
> +}
> +
> +static struct of_device_id syscon_reboot_of_match[] = {
> +	{ .compatible = "syscon-reboot" },
> +	{}
> +};
> +
> +static struct platform_driver syscon_reboot_driver = {
> +	.probe = syscon_reboot_probe,
> +	.driver = {
> +		.name = "syscon-reboot",
> +		.of_match_table = syscon_reboot_of_match,
> +	},
> +};
> +module_platform_driver(syscon_reboot_driver);
>

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH RESEND V9 1/6] power: reset: Add generic SYSCON register mapped reset
  2014-09-30 23:25 ` [PATCH RESEND V9 1/6] power: reset: Add generic SYSCON register mapped reset Feng Kan
  2014-10-01  3:11   ` Guenter Roeck
@ 2014-10-01 15:18   ` Sebastian Reichel
  1 sibling, 0 replies; 9+ messages in thread
From: Sebastian Reichel @ 2014-10-01 15:18 UTC (permalink / raw)
  To: linux-arm-kernel

Hi,

On Tue, Sep 30, 2014 at 04:25:03PM -0700, Feng Kan wrote:
> Add a generic SYSCON register mapped reset mechanism.
> 
> Signed-off-by: Feng Kan <fkan@apm.com>

I have merged the driver and its documentation to battery-2.6.git.
This should make it possible for the changes in arch/arm to be
merged via ARM maintainers in 3.19.

Please fix Guenter's comments in an incremental patch.

-- Sebastian
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^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2014-10-01 15:18 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2014-09-30 23:25 [PATCH RESEND V9 0/6] Add generic syscon reboot driver Feng Kan
2014-09-30 23:25 ` [PATCH RESEND V9 1/6] power: reset: Add generic SYSCON register mapped reset Feng Kan
2014-10-01  3:11   ` Guenter Roeck
2014-10-01 15:18   ` Sebastian Reichel
2014-09-30 23:25 ` [PATCH RESEND V9 2/6] Documentation: power: reset: Add documentation for generic SYSCON reboot driver Feng Kan
2014-09-30 23:25 ` [PATCH RESEND V9 3/6] Documentation: arm64: add SCU dts binding documentation to linux kernel Feng Kan
2014-09-30 23:25 ` [PATCH RESEND V9 4/6] arm64: dts: Add X-Gene reboot driver dts node Feng Kan
2014-09-30 23:25 ` [PATCH RESEND V9 5/6] arm64: Select reboot driver for X-Gene platform Feng Kan
2014-09-30 23:25 ` [PATCH RESEND V9 6/6] power: reset: Remove X-Gene reboot driver Feng Kan

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