Re: [PATCH v6 2/2] watchdog: Add new arm_smc_wdt watchdog driver
On 5/4/20 8:13 PM, Evan Benn wrote:
> From: Julius Werner
>
> This patch adds a watchdog driver that can be used on ARM systems
> with the appropriate watchdog implemented in Secure Monitor firmware.
> The driver communicates with firmware via a Secure Monitor Call.
> This may be useful for platforms using TrustZone that want
> the Secure Monitor firmware to have the final control over the watchdog.
>
> This is implemented on mt8173 chromebook devices oak, elm and hana in
> arm trusted firmware file plat/mediatek/mt8173/drivers/wdt/wdt.c.
>
> Signed-off-by: Julius Werner
> Signed-off-by: Evan Benn
Reviewed-by: Guenter Roeck
>
> ---
>
> Changes in v6:
> - Use default arm,smc-id value if non provided by dt
>
> Changes in v5:
> - Make timeleft return 0 on error
> - Use type punning on smc_func_id to save an alloc
> - Change compatible to arm,smc-wdt
>
> Changes in v4:
> - Get smc-id from of property
> - Return a1 instead of a0 in timeleft
>
> Changes in v3:
> - Add optional get_timeleft op
> - change name to arm_smc_wdt
>
> Changes in v2:
> - use watchdog_stop_on_reboot
> - use watchdog_stop_on_unregister
> - use devm_watchdog_register_device
> - remove smcwd_shutdown, smcwd_remove
> - change error codes
>
> MAINTAINERS| 1 +
> arch/arm64/configs/defconfig | 1 +
> drivers/watchdog/Kconfig | 13 +++
> drivers/watchdog/Makefile | 1 +
> drivers/watchdog/arm_smc_wdt.c | 188 +
> 5 files changed, 204 insertions(+)
> create mode 100644 drivers/watchdog/arm_smc_wdt.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 0f2b39767bfa9..2b782bbff200a 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1462,6 +1462,7 @@ M: Julius Werner
> R: Evan Benn
> S: Maintained
> F: devicetree/bindings/watchdog/arm-smc-wdt.yaml
> +F: drivers/watchdog/arm_smc_wdt.c
>
> ARM SMMU DRIVERS
> M: Will Deacon
> diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
> index 24e534d850454..0619df80f7575 100644
> --- a/arch/arm64/configs/defconfig
> +++ b/arch/arm64/configs/defconfig
> @@ -513,6 +513,7 @@ CONFIG_UNIPHIER_THERMAL=y
> CONFIG_WATCHDOG=y
> CONFIG_ARM_SP805_WATCHDOG=y
> CONFIG_ARM_SBSA_WATCHDOG=y
> +CONFIG_ARM_SMC_WATCHDOG=y
> CONFIG_S3C2410_WATCHDOG=y
> CONFIG_DW_WATCHDOG=y
> CONFIG_SUNXI_WATCHDOG=m
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index 0663c604bd642..c440b576d23bf 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -867,6 +867,19 @@ config DIGICOLOR_WATCHDOG
> To compile this driver as a module, choose M here: the
> module will be called digicolor_wdt.
>
> +config ARM_SMC_WATCHDOG
> + tristate "ARM Secure Monitor Call based watchdog support"
> + depends on ARM || ARM64
> + depends on OF
> + depends on HAVE_ARM_SMCCC
> + select WATCHDOG_CORE
> + help
> + Say Y here to include support for a watchdog timer
> + implemented by the EL3 Secure Monitor on ARM platforms.
> + Requires firmware support.
> + To compile this driver as a module, choose M here: the
> + module will be called arm_smc_wdt.
> +
> config LPC18XX_WATCHDOG
> tristate "LPC18xx/43xx Watchdog"
> depends on ARCH_LPC18XX || COMPILE_TEST
> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> index 6de2e4ceef190..97bed1d3d97cb 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -94,6 +94,7 @@ obj-$(CONFIG_UNIPHIER_WATCHDOG) += uniphier_wdt.o
> obj-$(CONFIG_RTD119X_WATCHDOG) += rtd119x_wdt.o
> obj-$(CONFIG_SPRD_WATCHDOG) += sprd_wdt.o
> obj-$(CONFIG_PM8916_WATCHDOG) += pm8916_wdt.o
> +obj-$(CONFIG_ARM_SMC_WATCHDOG) += arm_smc_wdt.o
>
> # X86 (i386 + ia64 + x86_64) Architecture
> obj-$(CONFIG_ACQUIRE_WDT) += acquirewdt.o
> diff --git a/drivers/watchdog/arm_smc_wdt.c b/drivers/watchdog/arm_smc_wdt.c
> new file mode 100644
> index 0..8f3d0c3a005fb
> --- /dev/null
> +++ b/drivers/watchdog/arm_smc_wdt.c
> @@ -0,0 +1,188 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * ARM Secure Monitor Call watchdog driver
> + *
> + * Copyright 2020 Google LLC.
> + * Julius Werner
> + * Based on mtk_wdt.c
> + */
> +
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +
> +#define DRV_NAME "arm_smc_wdt"
> +#define DRV_VERSION "1.0"
> +
> +enum smcwd_call {
> + SMCWD_INIT = 0,
> + SMCWD_SET_TIMEOUT = 1,
> + SMCWD_ENABLE= 2,
> + SMCWD_PET = 3,
> + SMCWD_GET_TIMELEFT = 4,
> +};
> +
> +static bool nowayout = WATCHDOG_NOWAYOUT;
> +static unsigned int timeout;
> +
> +static int smcwd_call(struct watchdog_device *wdd, enum smcwd_call call,
> + unsigned long arg, struct arm_smccc_res *res)
> +{
> + struct arm_smccc_res local_res;
> +
> + if (!res)
> +
Re: [PATCH v6 2/2] watchdog: Add new arm_smc_wdt watchdog driver
Tested on the Meson-A1.
Tested-by: Xingyu Chen
On 2020/5/5 11:13, Evan Benn wrote:
From: Julius Werner
This patch adds a watchdog driver that can be used on ARM systems
with the appropriate watchdog implemented in Secure Monitor firmware.
The driver communicates with firmware via a Secure Monitor Call.
This may be useful for platforms using TrustZone that want
the Secure Monitor firmware to have the final control over the watchdog.
This is implemented on mt8173 chromebook devices oak, elm and hana in
arm trusted firmware file plat/mediatek/mt8173/drivers/wdt/wdt.c.
Signed-off-by: Julius Werner
Signed-off-by: Evan Benn
---
Changes in v6:
- Use default arm,smc-id value if non provided by dt
Changes in v5:
- Make timeleft return 0 on error
- Use type punning on smc_func_id to save an alloc
- Change compatible to arm,smc-wdt
Changes in v4:
- Get smc-id from of property
- Return a1 instead of a0 in timeleft
Changes in v3:
- Add optional get_timeleft op
- change name to arm_smc_wdt
Changes in v2:
- use watchdog_stop_on_reboot
- use watchdog_stop_on_unregister
- use devm_watchdog_register_device
- remove smcwd_shutdown, smcwd_remove
- change error codes
MAINTAINERS| 1 +
arch/arm64/configs/defconfig | 1 +
drivers/watchdog/Kconfig | 13 +++
drivers/watchdog/Makefile | 1 +
drivers/watchdog/arm_smc_wdt.c | 188 +
5 files changed, 204 insertions(+)
create mode 100644 drivers/watchdog/arm_smc_wdt.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 0f2b39767bfa9..2b782bbff200a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1462,6 +1462,7 @@ M:Julius Werner
R:Evan Benn
S:Maintained
F:devicetree/bindings/watchdog/arm-smc-wdt.yaml
+F: drivers/watchdog/arm_smc_wdt.c
ARM SMMU DRIVERS
M:Will Deacon
diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index 24e534d850454..0619df80f7575 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -513,6 +513,7 @@ CONFIG_UNIPHIER_THERMAL=y
CONFIG_WATCHDOG=y
CONFIG_ARM_SP805_WATCHDOG=y
CONFIG_ARM_SBSA_WATCHDOG=y
+CONFIG_ARM_SMC_WATCHDOG=y
CONFIG_S3C2410_WATCHDOG=y
CONFIG_DW_WATCHDOG=y
CONFIG_SUNXI_WATCHDOG=m
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 0663c604bd642..c440b576d23bf 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -867,6 +867,19 @@ config DIGICOLOR_WATCHDOG
To compile this driver as a module, choose M here: the
module will be called digicolor_wdt.
+config ARM_SMC_WATCHDOG
+ tristate "ARM Secure Monitor Call based watchdog support"
+ depends on ARM || ARM64
+ depends on OF
+ depends on HAVE_ARM_SMCCC
+ select WATCHDOG_CORE
+ help
+ Say Y here to include support for a watchdog timer
+ implemented by the EL3 Secure Monitor on ARM platforms.
+ Requires firmware support.
+ To compile this driver as a module, choose M here: the
+ module will be called arm_smc_wdt.
+
config LPC18XX_WATCHDOG
tristate "LPC18xx/43xx Watchdog"
depends on ARCH_LPC18XX || COMPILE_TEST
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 6de2e4ceef190..97bed1d3d97cb 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -94,6 +94,7 @@ obj-$(CONFIG_UNIPHIER_WATCHDOG) += uniphier_wdt.o
obj-$(CONFIG_RTD119X_WATCHDOG) += rtd119x_wdt.o
obj-$(CONFIG_SPRD_WATCHDOG) += sprd_wdt.o
obj-$(CONFIG_PM8916_WATCHDOG) += pm8916_wdt.o
+obj-$(CONFIG_ARM_SMC_WATCHDOG) += arm_smc_wdt.o
# X86 (i386 + ia64 + x86_64) Architecture
obj-$(CONFIG_ACQUIRE_WDT) += acquirewdt.o
diff --git a/drivers/watchdog/arm_smc_wdt.c b/drivers/watchdog/arm_smc_wdt.c
new file mode 100644
index 0..8f3d0c3a005fb
--- /dev/null
+++ b/drivers/watchdog/arm_smc_wdt.c
@@ -0,0 +1,188 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ARM Secure Monitor Call watchdog driver
+ *
+ * Copyright 2020 Google LLC.
+ * Julius Werner
+ * Based on mtk_wdt.c
+ */
+
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#define DRV_NAME "arm_smc_wdt"
+#define DRV_VERSION"1.0"
+
+enum smcwd_call {
+ SMCWD_INIT = 0,
+ SMCWD_SET_TIMEOUT = 1,
+ SMCWD_ENABLE= 2,
+ SMCWD_PET = 3,
+ SMCWD_GET_TIMELEFT = 4,
+};
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+static unsigned int timeout;
+
+static int smcwd_call(struct watchdog_device *wdd, enum smcwd_call call,
+ unsigned long arg, struct arm_smccc_res *res)
+{
+ struct arm_smccc_res local_res;
+
+ if (!res)
+ res = _res;
+
+ arm_smccc_smc((u32)(uintptr_t)watchdog_get_drvdata(wdd), call, arg, 0,
+ 0, 0, 0, 0, res);
+
+ if (res->a0 == PSCI_RET_NOT_SUPPORTED)
+
Re: [PATCH v6 2/2] watchdog: Add new arm_smc_wdt watchdog driver
Reviewed-by: Julius Werner
[PATCH v6 2/2] watchdog: Add new arm_smc_wdt watchdog driver
From: Julius Werner
This patch adds a watchdog driver that can be used on ARM systems
with the appropriate watchdog implemented in Secure Monitor firmware.
The driver communicates with firmware via a Secure Monitor Call.
This may be useful for platforms using TrustZone that want
the Secure Monitor firmware to have the final control over the watchdog.
This is implemented on mt8173 chromebook devices oak, elm and hana in
arm trusted firmware file plat/mediatek/mt8173/drivers/wdt/wdt.c.
Signed-off-by: Julius Werner
Signed-off-by: Evan Benn
---
Changes in v6:
- Use default arm,smc-id value if non provided by dt
Changes in v5:
- Make timeleft return 0 on error
- Use type punning on smc_func_id to save an alloc
- Change compatible to arm,smc-wdt
Changes in v4:
- Get smc-id from of property
- Return a1 instead of a0 in timeleft
Changes in v3:
- Add optional get_timeleft op
- change name to arm_smc_wdt
Changes in v2:
- use watchdog_stop_on_reboot
- use watchdog_stop_on_unregister
- use devm_watchdog_register_device
- remove smcwd_shutdown, smcwd_remove
- change error codes
MAINTAINERS| 1 +
arch/arm64/configs/defconfig | 1 +
drivers/watchdog/Kconfig | 13 +++
drivers/watchdog/Makefile | 1 +
drivers/watchdog/arm_smc_wdt.c | 188 +
5 files changed, 204 insertions(+)
create mode 100644 drivers/watchdog/arm_smc_wdt.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 0f2b39767bfa9..2b782bbff200a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1462,6 +1462,7 @@ M:Julius Werner
R: Evan Benn
S: Maintained
F: devicetree/bindings/watchdog/arm-smc-wdt.yaml
+F: drivers/watchdog/arm_smc_wdt.c
ARM SMMU DRIVERS
M: Will Deacon
diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index 24e534d850454..0619df80f7575 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -513,6 +513,7 @@ CONFIG_UNIPHIER_THERMAL=y
CONFIG_WATCHDOG=y
CONFIG_ARM_SP805_WATCHDOG=y
CONFIG_ARM_SBSA_WATCHDOG=y
+CONFIG_ARM_SMC_WATCHDOG=y
CONFIG_S3C2410_WATCHDOG=y
CONFIG_DW_WATCHDOG=y
CONFIG_SUNXI_WATCHDOG=m
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 0663c604bd642..c440b576d23bf 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -867,6 +867,19 @@ config DIGICOLOR_WATCHDOG
To compile this driver as a module, choose M here: the
module will be called digicolor_wdt.
+config ARM_SMC_WATCHDOG
+ tristate "ARM Secure Monitor Call based watchdog support"
+ depends on ARM || ARM64
+ depends on OF
+ depends on HAVE_ARM_SMCCC
+ select WATCHDOG_CORE
+ help
+ Say Y here to include support for a watchdog timer
+ implemented by the EL3 Secure Monitor on ARM platforms.
+ Requires firmware support.
+ To compile this driver as a module, choose M here: the
+ module will be called arm_smc_wdt.
+
config LPC18XX_WATCHDOG
tristate "LPC18xx/43xx Watchdog"
depends on ARCH_LPC18XX || COMPILE_TEST
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 6de2e4ceef190..97bed1d3d97cb 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -94,6 +94,7 @@ obj-$(CONFIG_UNIPHIER_WATCHDOG) += uniphier_wdt.o
obj-$(CONFIG_RTD119X_WATCHDOG) += rtd119x_wdt.o
obj-$(CONFIG_SPRD_WATCHDOG) += sprd_wdt.o
obj-$(CONFIG_PM8916_WATCHDOG) += pm8916_wdt.o
+obj-$(CONFIG_ARM_SMC_WATCHDOG) += arm_smc_wdt.o
# X86 (i386 + ia64 + x86_64) Architecture
obj-$(CONFIG_ACQUIRE_WDT) += acquirewdt.o
diff --git a/drivers/watchdog/arm_smc_wdt.c b/drivers/watchdog/arm_smc_wdt.c
new file mode 100644
index 0..8f3d0c3a005fb
--- /dev/null
+++ b/drivers/watchdog/arm_smc_wdt.c
@@ -0,0 +1,188 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ARM Secure Monitor Call watchdog driver
+ *
+ * Copyright 2020 Google LLC.
+ * Julius Werner
+ * Based on mtk_wdt.c
+ */
+
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#define DRV_NAME "arm_smc_wdt"
+#define DRV_VERSION"1.0"
+
+enum smcwd_call {
+ SMCWD_INIT = 0,
+ SMCWD_SET_TIMEOUT = 1,
+ SMCWD_ENABLE= 2,
+ SMCWD_PET = 3,
+ SMCWD_GET_TIMELEFT = 4,
+};
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+static unsigned int timeout;
+
+static int smcwd_call(struct watchdog_device *wdd, enum smcwd_call call,
+ unsigned long arg, struct arm_smccc_res *res)
+{
+ struct arm_smccc_res local_res;
+
+ if (!res)
+ res = _res;
+
+ arm_smccc_smc((u32)(uintptr_t)watchdog_get_drvdata(wdd), call, arg, 0,
+ 0, 0, 0, 0, res);
+
+ if (res->a0 == PSCI_RET_NOT_SUPPORTED)
+ return -ENODEV;
+ if (res->a0 == PSCI_RET_INVALID_PARAMS)
+ return -EINVAL;
+ if
