[PATCH V6 0/5] Generic syscon reboot driver for APM X-Gene platforms

[PATCH V6 0/5] Generic syscon reboot driver for APM X-Gene platforms

[Feng Kan]

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

V6 Change:
	- Added reference in documenation for reference phandle

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 (5):
  power: reset: Add generic SYSCON register mapped reset
  power: reset: Remove X-Gene reboot driver
  arm64: dts: Add X-Gene reboot driver dts node
  arm64: Select reboot driver for X-Gene platform
  Documentation: power: reset: Add documentation for generic SYSCON
    reboot driver

 .../bindings/power/reset/syscon-reboot.txt         |   27 +++++
 arch/arm64/Kconfig                                 |    2 +
 arch/arm64/boot/dts/apm-storm.dtsi                 |   13 +++
 drivers/power/reset/Kconfig                        |    8 +-
 drivers/power/reset/Makefile                       |    2 +-
 drivers/power/reset/syscon-reboot.c                |  100 +++++++++++++++++++
 drivers/power/reset/xgene-reboot.c                 |  103 --------------------
 7 files changed, 147 insertions(+), 108 deletions(-)
 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

-- 
1.7.6.1

[PATCH V6 1/5] power: reset: Add generic SYSCON register mapped reset

[Feng Kan]

Add a generic SYSCON register mapped reset mechanism.

Signed-off-by: Feng Kan <fkan@apm.com>
---
 drivers/power/reset/Kconfig         |    7 +++
 drivers/power/reset/Makefile        |    1 +
 drivers/power/reset/syscon-reboot.c |  100 +++++++++++++++++++++++++++++++++++
 3 files changed, 108 insertions(+), 0 deletions(-)
 create mode 100644 drivers/power/reset/syscon-reboot.c

diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index fa0e4e0..9931b61 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -57,3 +57,10 @@ config POWER_RESET_XGENE
 	depends on POWER_RESET
 	help
 	  Reboot support for the APM SoC X-Gene Eval boards.
+
+config POWER_RESET_SYSCON
+	bool "Generic SYSCON regmap reset driver"
+	depends on MFD_SYSCON
+	depends on POWER_RESET
+	help
+	  Reboot support for generic SYSCON mapped register reset.
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index a5b4a77..94883ed 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -5,3 +5,4 @@ obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
 obj-$(CONFIG_POWER_RESET_RESTART) += restart-poweroff.o
 obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o
 obj-$(CONFIG_POWER_RESET_XGENE) += xgene-reboot.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..29ed908
--- /dev/null
+++ b/drivers/power/reset/syscon-reboot.c
@@ -0,0 +1,100 @@
+/*
+ * 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.
+ *
+ * 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 <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/reboot.h>
+#include <asm/system_misc.h>
+
+struct syscon_reboot_context {
+	struct regmap *map;
+	u32 offset;
+	u32 mask;
+};
+
+static struct syscon_reboot_context *syscon_reboot_ctx;
+
+static void syscon_restart(enum reboot_mode reboot_mode, const char *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");
+}
+
+static int syscon_reboot_probe(struct platform_device *pdev)
+{
+	struct syscon_reboot_context *ctx;
+	struct device *dev = &pdev->dev;
+
+	ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx) {
+		dev_err(&pdev->dev, "out of memory for context\n");
+		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;
+
+	arm_pm_restart = syscon_restart;
+	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);
-- 
1.7.6.1

[PATCH V6 2/5] arm64: dts: Add X-Gene reboot driver dts node

[Feng Kan]

Add X-Gene platform reboot driver dts node.

Signed-off-by: Feng Kan <fkan@apm.com>
---
 arch/arm64/boot/dts/apm-storm.dtsi |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/arch/arm64/boot/dts/apm-storm.dtsi b/arch/arm64/boot/dts/apm-storm.dtsi
index 93f4b2d..306a9cd 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@17000000 {
+			compatible = "apm,xgene-scu","syscon";
+			reg = <0x0 0x17000000 0x0 0x400>;
+		};
+
 		clocks {
 			#address-cells = <2>;
 			#size-cells = <2>;
@@ -339,5 +344,12 @@
 			phys = <&phy3 0>;
 			phy-names = "sata-phy";
 		};
+
+		reboot@17000014 {
+			compatible = "syscon-reboot";
+			regmap = <&scu>;
+			offset = <0x14>;
+			mask = <0x1>;
+		};
 	};
 };
-- 
1.7.6.1

[PATCH V6 3/5] Documentation: power: reset: Add documentation for generic SYSCON reboot driver

[Feng Kan]

Add documentation for generic SYSCON reboot driver.

Signed-off-by: Feng Kan <fkan@apm.com>
---
 .../bindings/power/reset/syscon-reboot.txt         |   27 ++++++++++++++++++++
 1 files changed, 27 insertions(+), 0 deletions(-)
 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..79942a3
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/reset/syscon-reboot.txt
@@ -0,0 +1,27 @@
+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:
+	regmapnode {
+		compatible = "apm,xgene-scu","syscon";
+		reg = <0xXXXXXXXX 0xXXXXXXXX>;
+	}
+
+	reboot {
+	   compatible = "syscon-reboot";
+	   regmap = <&regmapnode>;
+	   offset = <0x0>;
+	   mask = <0x1>;
+	};
-- 
1.7.6.1

[PATCH V6 4/5] power: reset: Remove X-Gene reboot driver

[Feng Kan]

Remove X-Gene reboot driver.

Signed-off-by: Feng Kan <fkan@apm.com>
---
 drivers/power/reset/Kconfig        |    7 ---
 drivers/power/reset/Makefile       |    1 -
 drivers/power/reset/xgene-reboot.c |  103 ------------------------------------
 3 files changed, 0 insertions(+), 111 deletions(-)
 delete mode 100644 drivers/power/reset/xgene-reboot.c

diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 9931b61..7a8424b 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -51,13 +51,6 @@ 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
-	depends on POWER_RESET
-	help
-	  Reboot support for the APM SoC X-Gene Eval boards.
-
 config POWER_RESET_SYSCON
 	bool "Generic SYSCON regmap reset driver"
 	depends on MFD_SYSCON
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 94883ed..ae1711a 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -4,5 +4,4 @@ obj-$(CONFIG_POWER_RESET_MSM) += msm-poweroff.o
 obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
 obj-$(CONFIG_POWER_RESET_RESTART) += restart-poweroff.o
 obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o
-obj-$(CONFIG_POWER_RESET_XGENE) += xgene-reboot.o
 obj-$(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 ecd55f8..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(char str, 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);
-- 
1.7.6.1

[PATCH V6 5/5] arm64: Select reboot driver for X-Gene platform

[Feng Kan]

Select reboot driver for X-Gene platform.

Signed-off-by: Feng Kan <fkan@apm.com>
---
 arch/arm64/Kconfig |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 9711a5f..007f340 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -129,6 +129,8 @@ 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
 
-- 
1.7.6.1