[PATCH V2 0/4] Add i.MX8QXP system controller watchdog support

[PATCH V2 0/4] Add i.MX8QXP system controller watchdog support

[Anson Huang]

i.MX8QXP is an ARMv8 Cortex-A35 SoC with a Cortex-M4 system controller inside,
the system controller manages overall power, clock, secure RTC and watchdog
etc., so Linux kernel running on A35 needs to communicate with system
controller for watchdog operation, this system controller watchdog will
call SMC to trap to EL3 secure world ARM-Trusted-Firmware and then it will
request system controller to do the watchdog operation via IPC.

Below are the patch dependency:

The dt-binding and imx8qxp.dtsi patch are based on my thermal patch series as below:
https://patchwork.kernel.org/patch/10800699/

Anson Huang (4):
  dt-bindings: fsl: scu: add watchdog binding
  watchdog: imx_sc: Add i.MX system controller watchdog support
  arm64: defconfig: add support for i.MX system controller watchdog
  arm64: dts: freescale: imx8qxp: add watchdog support

 .../devicetree/bindings/arm/freescale/fsl,scu.txt  |  10 +
 arch/arm64/boot/dts/freescale/imx8qxp.dtsi         |   4 +
 arch/arm64/configs/defconfig                       |   1 +
 drivers/watchdog/Kconfig                           |  13 ++
 drivers/watchdog/Makefile                          |   1 +
 drivers/watchdog/imx_sc_wdt.c                      | 210 +++++++++++++++++++++
 6 files changed, 239 insertions(+)
 create mode 100644 drivers/watchdog/imx_sc_wdt.c

-- 
2.7.4

[PATCH V2 1/4] dt-bindings: fsl: scu: add watchdog binding

[Anson Huang]

Add i.MX8QXP system controller watchdog binding.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
Note: this patch is based on my thermal patch series: https://patchwork.kernel.org/patch/10800699/
---
 Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
index 4b79751..f388ec6 100644
--- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
+++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
@@ -136,6 +136,12 @@ Required properties:
 			   resource id for thermal driver to get temperature via
 			   SCU IPC.
 
+Watchdog bindings based on SCU Message Protocol
+------------------------------------------------------------
+
+Required properties:
+- compatible: should be "fsl,imx8qxp-sc-wdt";
+
 Example (imx8qxp):
 -------------
 lsio_mu1: mailbox@5d1c0000 {
@@ -188,6 +194,10 @@ firmware {
 			tsens-num = <1>;
 			#thermal-sensor-cells = <1>;
 		};
+
+		watchdog: watchdog {
+			compatible = "fsl,imx8qxp-sc-wdt";
+		};
 	};
 };
 
-- 
2.7.4

[PATCH V2 2/4] watchdog: imx_sc: Add i.MX system controller watchdog support

[Anson Huang]

i.MX8QXP is an ARMv8 SoC which has a Cortex-M4 system controller
inside, the system controller is in charge of controlling power,
clock and watchdog etc..

This patch adds i.MX system controller watchdog driver support,
watchdog operation needs to be done in secure EL3 mode via
ARM-Trusted-Firmware, using SMC call, CPU will trap into
ARM-Trusted-Firmware and then it will request system controller
to do watchdog operation via IPC.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
 drivers/watchdog/Kconfig      |  13 +++
 drivers/watchdog/Makefile     |   1 +
 drivers/watchdog/imx_sc_wdt.c | 187 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 201 insertions(+)
 create mode 100644 drivers/watchdog/imx_sc_wdt.c

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 65c3c42..5c5b8ba 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -625,6 +625,19 @@ config IMX2_WDT
 	  To compile this driver as a module, choose M here: the
 	  module will be called imx2_wdt.
 
+config IMX_SC_WDT
+	tristate "IMX SC Watchdog"
+	depends on ARCH_MXC || COMPILE_TEST
+	select WATCHDOG_CORE
+	help
+	  This is the driver for the system controller watchdog
+	  on the NXP i.MX SoCs with system controller inside.
+	  If you have one of these processors and wish to have
+	  watchdog support enabled, say Y, otherwise say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called imx_sc_wdt.
+
 config UX500_WATCHDOG
 	tristate "ST-Ericsson Ux500 watchdog"
 	depends on MFD_DB8500_PRCMU
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 4e78a8c..0c9da63 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -68,6 +68,7 @@ obj-$(CONFIG_NUC900_WATCHDOG) += nuc900_wdt.o
 obj-$(CONFIG_TS4800_WATCHDOG) += ts4800_wdt.o
 obj-$(CONFIG_TS72XX_WATCHDOG) += ts72xx_wdt.o
 obj-$(CONFIG_IMX2_WDT) += imx2_wdt.o
+obj-$(CONFIG_IMX_SC_WDT) += imx_sc_wdt.o
 obj-$(CONFIG_UX500_WATCHDOG) += ux500_wdt.o
 obj-$(CONFIG_RETU_WATCHDOG) += retu_wdt.o
 obj-$(CONFIG_BCM2835_WDT) += bcm2835_wdt.o
diff --git a/drivers/watchdog/imx_sc_wdt.c b/drivers/watchdog/imx_sc_wdt.c
new file mode 100644
index 0000000..5af6cf2
--- /dev/null
+++ b/drivers/watchdog/imx_sc_wdt.c
@@ -0,0 +1,187 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2018-2019 NXP.
+ */
+
+#include <linux/arm-smccc.h>
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+#include <linux/watchdog.h>
+
+#define DEFAULT_TIMEOUT 60
+/*
+ * Software timer tick implemented in scfw side, support 10ms to 0xffffffff ms
+ * in theory, but for normal case, 1s~128s is enough, you can change this max
+ * value in case it's not enough.
+ */
+#define MAX_TIMEOUT 128
+
+#define IMX_SIP_TIMER			0xC2000002
+#define IMX_SIP_TIMER_START_WDOG		0x01
+#define IMX_SIP_TIMER_STOP_WDOG		0x02
+#define IMX_SIP_TIMER_SET_WDOG_ACT	0x03
+#define IMX_SIP_TIMER_PING_WDOG		0x04
+#define IMX_SIP_TIMER_SET_TIMEOUT_WDOG	0x05
+#define IMX_SIP_TIMER_GET_WDOG_STAT	0x06
+#define IMX_SIP_TIMER_SET_PRETIME_WDOG	0x07
+
+#define SC_TIMER_WDOG_ACTION_PARTITION	0
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0000);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
+		 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+static unsigned int timeout = DEFAULT_TIMEOUT;
+module_param(timeout, uint, 0000);
+MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds (default="
+		 __MODULE_STRING(DEFAULT_TIMEOUT) ")");
+
+static int imx_sc_wdt_ping(struct watchdog_device *wdog)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_PING_WDOG,
+		      0, 0, 0, 0, 0, 0, &res);
+
+	return res.a0;
+}
+
+static int imx_sc_wdt_start(struct watchdog_device *wdog)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_START_WDOG,
+		      0, 0, 0, 0, 0, 0, &res);
+	if (res.a0)
+		return res.a0;
+
+	arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_SET_WDOG_ACT,
+		      SC_TIMER_WDOG_ACTION_PARTITION,
+		      0, 0, 0, 0, 0, &res);
+	return res.a0;
+}
+
+static int imx_sc_wdt_stop(struct watchdog_device *wdog)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_STOP_WDOG,
+		      0, 0, 0, 0, 0, 0, &res);
+
+	return res.a0;
+}
+
+static int imx_sc_wdt_set_timeout(struct watchdog_device *wdog,
+				unsigned int timeout)
+{
+	struct arm_smccc_res res;
+
+	wdog->timeout = timeout;
+	arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_SET_TIMEOUT_WDOG,
+		      timeout * 1000, 0, 0, 0, 0, 0, &res);
+
+	return res.a0;
+}
+
+static const struct watchdog_ops imx_sc_wdt_ops = {
+	.owner = THIS_MODULE,
+	.start = imx_sc_wdt_start,
+	.stop  = imx_sc_wdt_stop,
+	.ping  = imx_sc_wdt_ping,
+	.set_timeout = imx_sc_wdt_set_timeout,
+};
+
+static const struct watchdog_info imx_sc_wdt_info = {
+	.identity	= "i.MX SC watchdog timer",
+	.options	= WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING |
+			  WDIOF_MAGICCLOSE | WDIOF_PRETIMEOUT,
+};
+
+static int imx_sc_wdt_probe(struct platform_device *pdev)
+{
+	struct watchdog_device *imx_sc_wdd;
+	int ret;
+
+	imx_sc_wdd = devm_kzalloc(&pdev->dev, sizeof(*imx_sc_wdd), GFP_KERNEL);
+	if (!imx_sc_wdd)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, imx_sc_wdd);
+
+	imx_sc_wdd->info = &imx_sc_wdt_info;
+	imx_sc_wdd->ops = &imx_sc_wdt_ops;
+	imx_sc_wdd->min_timeout = 1;
+	imx_sc_wdd->max_timeout = MAX_TIMEOUT;
+	imx_sc_wdd->parent = &pdev->dev;
+
+	ret = watchdog_init_timeout(imx_sc_wdd, DEFAULT_TIMEOUT, &pdev->dev);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to init the wdog timeout:%d\n",
+			ret);
+		return ret;
+	}
+
+	watchdog_stop_on_reboot(imx_sc_wdd);
+	watchdog_stop_on_unregister(imx_sc_wdd);
+
+	ret = devm_watchdog_register_device(&pdev->dev, imx_sc_wdd);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to register watchdog device\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct of_device_id imx_sc_wdt_dt_ids[] = {
+	{ .compatible = "fsl,imx8qxp-sc-wdt", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx_sc_wdt_dt_ids);
+
+#ifdef CONFIG_PM_SLEEP
+static int imx_sc_wdt_suspend(struct device *dev)
+{
+	struct watchdog_device *imx_sc_wdd = dev_get_drvdata(dev);
+
+	if (watchdog_active(imx_sc_wdd))
+		imx_sc_wdt_stop(imx_sc_wdd);
+
+	return 0;
+}
+
+static int imx_sc_wdt_resume(struct device *dev)
+{
+	struct watchdog_device *imx_sc_wdd = dev_get_drvdata(dev);
+
+	if (watchdog_active(imx_sc_wdd))
+		imx_sc_wdt_start(imx_sc_wdd);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(imx_sc_wdt_pm_ops,
+			 imx_sc_wdt_suspend, imx_sc_wdt_resume);
+
+static struct platform_driver imx_sc_wdt_driver = {
+	.probe		= imx_sc_wdt_probe,
+	.driver		= {
+		.name	= "imx-sc-wdt",
+		.of_match_table = imx_sc_wdt_dt_ids,
+		.pm	= &imx_sc_wdt_pm_ops,
+	},
+};
+
+module_platform_driver(imx_sc_wdt_driver);
+
+MODULE_AUTHOR("Robin Gong <yibin.gong@nxp.com>");
+MODULE_DESCRIPTION("NXP i.MX system controller watchdog driver");
+MODULE_LICENSE("GPL v2");
-- 
2.7.4

[PATCH V2 3/4] arm64: defconfig: add support for i.MX system controller watchdog

[Anson Huang]

Enable CONFIG_IMX_SC_WDT as module to support i.MX system
controller watchdog.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
 arch/arm64/configs/defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index 2d9c390..690f4ba 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -427,6 +427,7 @@ CONFIG_WATCHDOG=y
 CONFIG_ARM_SP805_WATCHDOG=y
 CONFIG_S3C2410_WATCHDOG=y
 CONFIG_IMX2_WDT=y
+CONFIG_IMX_SC_WDT=m
 CONFIG_MESON_GXBB_WATCHDOG=m
 CONFIG_MESON_WATCHDOG=m
 CONFIG_RENESAS_WDT=y
-- 
2.7.4

[PATCH V2 4/4] arm64: dts: freescale: imx8qxp: add watchdog support

[Anson Huang]

Add i.MX8QXP system controller watchdog support.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
Note: this patch is based on my thermal patch series: https://patchwork.kernel.org/patch/10800699/
---
 arch/arm64/boot/dts/freescale/imx8qxp.dtsi | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/imx8qxp.dtsi b/arch/arm64/boot/dts/freescale/imx8qxp.dtsi
index 88eb04b..bfb77a5 100644
--- a/arch/arm64/boot/dts/freescale/imx8qxp.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8qxp.dtsi
@@ -123,6 +123,10 @@
 			tsens-num = <1>;
 			#thermal-sensor-cells = <1>;
 		};
+
+		watchdog: watchdog {
+			compatible = "fsl,imx8qxp-sc-wdt";
+		};
 	};
 
 	timer {
-- 
2.7.4

Re: [PATCH V2 0/4] Add i.MX8QXP system controller watchdog support

[Guenter Roeck]

On 2/17/19 6:01 PM, Anson Huang wrote:
> i.MX8QXP is an ARMv8 Cortex-A35 SoC with a Cortex-M4 system controller inside,
> the system controller manages overall power, clock, secure RTC and watchdog
> etc., so Linux kernel running on A35 needs to communicate with system
> controller for watchdog operation, this system controller watchdog will
> call SMC to trap to EL3 secure world ARM-Trusted-Firmware and then it will
> request system controller to do the watchdog operation via IPC.
> 
> 
And you expect I'll spend the time comparing this version of the patch
series against version 1 and figure out myself what exactly changed ?

Guenter

Below are the patch dependency:
> 
> The dt-binding and imx8qxp.dtsi patch are based on my thermal patch series as below:
> https://patchwork.kernel.org/patch/10800699/
> 
> Anson Huang (4):
>    dt-bindings: fsl: scu: add watchdog binding
>    watchdog: imx_sc: Add i.MX system controller watchdog support
>    arm64: defconfig: add support for i.MX system controller watchdog
>    arm64: dts: freescale: imx8qxp: add watchdog support
> 
>   .../devicetree/bindings/arm/freescale/fsl,scu.txt  |  10 +
>   arch/arm64/boot/dts/freescale/imx8qxp.dtsi         |   4 +
>   arch/arm64/configs/defconfig                       |   1 +
>   drivers/watchdog/Kconfig                           |  13 ++
>   drivers/watchdog/Makefile                          |   1 +
>   drivers/watchdog/imx_sc_wdt.c                      | 210 +++++++++++++++++++++
>   6 files changed, 239 insertions(+)
>   create mode 100644 drivers/watchdog/imx_sc_wdt.c
> 

RE: [PATCH V2 0/4] Add i.MX8QXP system controller watchdog support

[Anson Huang]

Hi, Guenter

Best Regards!
Anson Huang

> -----Original Message-----
> From: Guenter Roeck [mailto:groeck7@gmail.com] On Behalf Of Guenter
> Roeck
> Sent: 2019年2月18日 13:16
> To: Anson Huang <anson.huang@nxp.com>; robh+dt@kernel.org;
> mark.rutland@arm.com; shawnguo@kernel.org; s.hauer@pengutronix.de;
> kernel@pengutronix.de; festevam@gmail.com; catalin.marinas@arm.com;
> will.deacon@arm.com; wim@linux-watchdog.org; Aisheng Dong
> <aisheng.dong@nxp.com>; ulf.hansson@linaro.org; Daniel Baluta
> <daniel.baluta@nxp.com>; Andy Gross <andy.gross@linaro.org>;
> horms+renesas@verge.net.au; heiko@sntech.de; arnd@arndb.de;
> bjorn.andersson@linaro.org; jagan@amarulasolutions.com;
> enric.balletbo@collabora.com; marc.w.gonzalez@free.fr; olof@lixom.net;
> devicetree@vger.kernel.org; linux-kernel@vger.kernel.org; linux-arm-
> kernel@lists.infradead.org; linux-watchdog@vger.kernel.org
> Cc: dl-linux-imx <linux-imx@nxp.com>
> Subject: Re: [PATCH V2 0/4] Add i.MX8QXP system controller watchdog
> support
> 
> On 2/17/19 6:01 PM, Anson Huang wrote:
> > i.MX8QXP is an ARMv8 Cortex-A35 SoC with a Cortex-M4 system controller
> > inside, the system controller manages overall power, clock, secure RTC
> > and watchdog etc., so Linux kernel running on A35 needs to communicate
> > with system controller for watchdog operation, this system controller
> > watchdog will call SMC to trap to EL3 secure world
> > ARM-Trusted-Firmware and then it will request system controller to do the
> watchdog operation via IPC.
> >
> >
> And you expect I'll spend the time comparing this version of the patch series
> against version 1 and figure out myself what exactly changed ?
> 
> Guenter

Sorry, I planned to reply your review mail but forgot, I addressed all your comments
in V2 patch set, I will add the change log in V2 watchdog driver patch and resend.

Anson.

> 
> Below are the patch dependency:
> >
> > The dt-binding and imx8qxp.dtsi patch are based on my thermal patch
> series as below:
> >
> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpat
> >
> chwork.kernel.org%2Fpatch%2F10800699%2F&amp;data=02%7C01%7Canso
> n.huang
> > %40nxp.com%7C630e6c5d7ed04a912f7708d695603cb2%7C686ea1d3bc2b4
> c6fa92cd9
> >
> 9c5c301635%7C0%7C0%7C636860637903984268&amp;sdata=a25qJs%2Fb4e
> 2a9Ey77U
> > gTNKAGCQ8IWRcUKb4G0lK%2Bkjc%3D&amp;reserved=0
> >
> > Anson Huang (4):
> >    dt-bindings: fsl: scu: add watchdog binding
> >    watchdog: imx_sc: Add i.MX system controller watchdog support
> >    arm64: defconfig: add support for i.MX system controller watchdog
> >    arm64: dts: freescale: imx8qxp: add watchdog support
> >
> >   .../devicetree/bindings/arm/freescale/fsl,scu.txt  |  10 +
> >   arch/arm64/boot/dts/freescale/imx8qxp.dtsi         |   4 +
> >   arch/arm64/configs/defconfig                       |   1 +
> >   drivers/watchdog/Kconfig                           |  13 ++
> >   drivers/watchdog/Makefile                          |   1 +
> >   drivers/watchdog/imx_sc_wdt.c                      | 210
> +++++++++++++++++++++
> >   6 files changed, 239 insertions(+)
> >   create mode 100644 drivers/watchdog/imx_sc_wdt.c
> >