Enable reboot driver for the X-Gene platform. Add generic syscon reboot
driver.
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 (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 | 23 +++++
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, 143 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
This add documentation for the SCU system clock unit device tree binding
to the kernel.
Signed-off-by: Feng Kan <[email protected]>
---
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@17000000 {
+ compatible = "apm,xgene-scu","syscon";
+ reg = <0x0 0x17000000 0x0 0x400>;
+ };
--
1.9.1
Select reboot driver for X-Gene platform.
Signed-off-by: Feng Kan <[email protected]>
---
arch/arm64/Kconfig | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index a474de34..91a2e25 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -140,6 +140,8 @@ 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
Remove X-Gene reboot driver.
Signed-off-by: Feng Kan <[email protected]>
---
drivers/power/reset/Kconfig | 7 ---
drivers/power/reset/Makefile | 1 -
drivers/power/reset/xgene-reboot.c | 103 -------------------------------------
3 files changed, 111 deletions(-)
delete mode 100644 drivers/power/reset/xgene-reboot.c
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 7035236..cfe444e 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -66,13 +66,6 @@ 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_KEYSTONE
bool "Keystone reset driver"
depends on ARCH_KEYSTONE
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index b1b5ab3..62088d8 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -6,6 +6,5 @@ obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
obj-$(CONFIG_POWER_RESET_RESTART) += restart-poweroff.o
obj-$(CONFIG_POWER_RESET_SUN6I) += sun6i-reboot.o
obj-$(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 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 <[email protected]>
- * Author: Loc Ho <[email protected]>
- *
- * 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);
--
1.9.1
Add X-Gene platform reboot driver dts node.
Signed-off-by: Feng Kan <[email protected]>
---
arch/arm64/boot/dts/apm-storm.dtsi | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/arch/arm64/boot/dts/apm-storm.dtsi b/arch/arm64/boot/dts/apm-storm.dtsi
index 40aa96c..53e70f8 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>;
@@ -397,5 +402,12 @@
#clock-cells = <1>;
clocks = <&rtcclk 0>;
};
+
+ reboot@17000014 {
+ compatible = "syscon-reboot";
+ regmap = <&scu>;
+ offset = <0x14>;
+ mask = <0x1>;
+ };
};
};
--
1.9.1
Add a generic SYSCON register mapped reset mechanism.
Signed-off-by: Feng Kan <[email protected]>
---
drivers/power/reset/Kconfig | 6 +++
drivers/power/reset/Makefile | 1 +
drivers/power/reset/syscon-reboot.c | 91 +++++++++++++++++++++++++++++++++++++
3 files changed, 98 insertions(+)
create mode 100644 drivers/power/reset/syscon-reboot.c
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index bdcf517..7035236 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -80,3 +80,9 @@ config POWER_RESET_KEYSTONE
help
Reboot support for the KEYSTONE SoCs.
+config POWER_RESET_SYSCON
+ bool "Generic SYSCON regmap reset driver"
+ depends on ARCH_XGENE
+ depends on POWER_RESET && MFD_SYSCON
+ help
+ Reboot support for generic SYSCON mapped register reset.
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index dde2e8b..b1b5ab3 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -8,3 +8,4 @@ obj-$(CONFIG_POWER_RESET_SUN6I) += sun6i-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..9c15ba5
--- /dev/null
+++ b/drivers/power/reset/syscon-reboot.c
@@ -0,0 +1,91 @@
+/*
+ * Generic Syscon Reboot Driver
+ *
+ * Copyright (c) 2013, Applied Micro Circuits Corporation
+ * Author: Feng Kan <[email protected]>
+ *
+ * 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/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);
--
1.9.1
Add documentation for generic SYSCON reboot driver.
Signed-off-by: Feng Kan <[email protected]>
---
.../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 = <®mapnode>;
+ offset = <0x0>;
+ mask = <0x1>;
+ };
--
1.9.1
On Thu, Jun 26, 2014 at 7:03 AM, Feng Kan <[email protected]> wrote:
> Add a generic SYSCON register mapped reset mechanism.
>
> Signed-off-by: Feng Kan <[email protected]>
> ---
> drivers/power/reset/Kconfig | 6 +++
> drivers/power/reset/Makefile | 1 +
> drivers/power/reset/syscon-reboot.c | 91 +++++++++++++++++++++++++++++++++++++
> 3 files changed, 98 insertions(+)
> create mode 100644 drivers/power/reset/syscon-reboot.c
>
> diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
> index bdcf517..7035236 100644
> --- a/drivers/power/reset/Kconfig
> +++ b/drivers/power/reset/Kconfig
> @@ -80,3 +80,9 @@ config POWER_RESET_KEYSTONE
> help
> Reboot support for the KEYSTONE SoCs.
>
> +config POWER_RESET_SYSCON
> + bool "Generic SYSCON regmap reset driver"
> + depends on ARCH_XGENE
If this is supposed to be generic, why are you depending on
a certain platform?
ChenYu
> + depends on POWER_RESET && MFD_SYSCON
> + help
> + Reboot support for generic SYSCON mapped register reset.
> diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
> index dde2e8b..b1b5ab3 100644
> --- a/drivers/power/reset/Makefile
> +++ b/drivers/power/reset/Makefile
> @@ -8,3 +8,4 @@ obj-$(CONFIG_POWER_RESET_SUN6I) += sun6i-reboot.o
> obj-$(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..9c15ba5
> --- /dev/null
> +++ b/drivers/power/reset/syscon-reboot.c
> @@ -0,0 +1,91 @@
> +/*
> + * Generic Syscon Reboot Driver
> + *
> + * Copyright (c) 2013, Applied Micro Circuits Corporation
> + * Author: Feng Kan <[email protected]>
> + *
> + * 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/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);
> --
> 1.9.1
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On Wed, Jun 25, 2014 at 6:38 PM, Chen-Yu Tsai <[email protected]> wrote:
> On Thu, Jun 26, 2014 at 7:03 AM, Feng Kan <[email protected]> wrote:
>> Add a generic SYSCON register mapped reset mechanism.
>>
>> Signed-off-by: Feng Kan <[email protected]>
>> ---
>> drivers/power/reset/Kconfig | 6 +++
>> drivers/power/reset/Makefile | 1 +
>> drivers/power/reset/syscon-reboot.c | 91 +++++++++++++++++++++++++++++++++++++
>> 3 files changed, 98 insertions(+)
>> create mode 100644 drivers/power/reset/syscon-reboot.c
>>
>> diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
>> index bdcf517..7035236 100644
>> --- a/drivers/power/reset/Kconfig
>> +++ b/drivers/power/reset/Kconfig
>> @@ -80,3 +80,9 @@ config POWER_RESET_KEYSTONE
>> help
>> Reboot support for the KEYSTONE SoCs.
>>
>> +config POWER_RESET_SYSCON
>> + bool "Generic SYSCON regmap reset driver"
>> + depends on ARCH_XGENE
>
> If this is supposed to be generic, why are you depending on
> a certain platform?
Yes, the problem was that it was breaking the x86 build.
>
>
> ChenYu
>
>> + depends on POWER_RESET && MFD_SYSCON
>> + help
>> + Reboot support for generic SYSCON mapped register reset.
>> diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
>> index dde2e8b..b1b5ab3 100644
>> --- a/drivers/power/reset/Makefile
>> +++ b/drivers/power/reset/Makefile
>> @@ -8,3 +8,4 @@ obj-$(CONFIG_POWER_RESET_SUN6I) += sun6i-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..9c15ba5
>> --- /dev/null
>> +++ b/drivers/power/reset/syscon-reboot.c
>> @@ -0,0 +1,91 @@
>> +/*
>> + * Generic Syscon Reboot Driver
>> + *
>> + * Copyright (c) 2013, Applied Micro Circuits Corporation
>> + * Author: Feng Kan <[email protected]>
>> + *
>> + * 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/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);
>> --
>> 1.9.1
>>
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> [email protected]
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On Thursday 26 June 2014 09:51:14 Feng Kan wrote:
> >> diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
> >> index bdcf517..7035236 100644
> >> --- a/drivers/power/reset/Kconfig
> >> +++ b/drivers/power/reset/Kconfig
> >> @@ -80,3 +80,9 @@ config POWER_RESET_KEYSTONE
> >> help
> >> Reboot support for the KEYSTONE SoCs.
> >>
> >> +config POWER_RESET_SYSCON
> >> + bool "Generic SYSCON regmap reset driver"
> >> + depends on ARCH_XGENE
> >
> > If this is supposed to be generic, why are you depending on
> > a certain platform?
>
> Yes, the problem was that it was breaking the x86 build.
You probably need to list the exact dependencies then, at least make
it depend on MFD_SYSCON and OF. We generally want all drivers to
build without warnings on all architectures. You can limit it to
(ARM || ARM64 || COMPILE_TEST) if you don't want it to show up on
x86 by default, but it should still be possible to build it when
COMPILE_TEST is set.
Arnd