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* [PATCH V4 1/4] dt-bindings: watchdog: Add i.MX7ULP bindings
@ 2019-08-22  2:37 Anson Huang
  2019-08-22  2:37 ` [PATCH V4 2/4] watchdog: Add i.MX7ULP watchdog support Anson Huang
                   ` (4 more replies)
  0 siblings, 5 replies; 8+ messages in thread
From: Anson Huang @ 2019-08-22  2:37 UTC (permalink / raw)
  To: wim, linux, robh+dt, mark.rutland, shawnguo, s.hauer, kernel,
	festevam, linux, otavio, leonard.crestez, schnitzeltony,
	u.kleine-koenig, jan.tuerk, linux-watchdog, devicetree,
	linux-arm-kernel, linux-kernel
  Cc: Linux-imx

Add the watchdog bindings for Freescale i.MX7ULP.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
No changes.
---
 .../bindings/watchdog/fsl-imx7ulp-wdt.txt          | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/watchdog/fsl-imx7ulp-wdt.txt

diff --git a/Documentation/devicetree/bindings/watchdog/fsl-imx7ulp-wdt.txt b/Documentation/devicetree/bindings/watchdog/fsl-imx7ulp-wdt.txt
new file mode 100644
index 0000000..d83fc5c
--- /dev/null
+++ b/Documentation/devicetree/bindings/watchdog/fsl-imx7ulp-wdt.txt
@@ -0,0 +1,22 @@
+* Freescale i.MX7ULP Watchdog Timer (WDT) Controller
+
+Required properties:
+- compatible : Should be "fsl,imx7ulp-wdt"
+- reg : Should contain WDT registers location and length
+- interrupts : Should contain WDT interrupt
+- clocks: Should contain a phandle pointing to the gated peripheral clock.
+
+Optional properties:
+- timeout-sec : Contains the watchdog timeout in seconds
+
+Examples:
+
+wdog1: wdog@403d0000 {
+	compatible = "fsl,imx7ulp-wdt";
+	reg = <0x403d0000 0x10000>;
+	interrupts = <GIC_SPI 55 IRQ_TYPE_LEVEL_HIGH>;
+	clocks = <&pcc2 IMX7ULP_CLK_WDG1>;
+	assigned-clocks = <&pcc2 IMX7ULP_CLK_WDG1>;
+	assigned-clocks-parents = <&scg1 IMX7ULP_CLK_FIRC_BUS_CLK>;
+	timeout-sec = <40>;
+};
-- 
2.7.4


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH V4 2/4] watchdog: Add i.MX7ULP watchdog support
  2019-08-22  2:37 [PATCH V4 1/4] dt-bindings: watchdog: Add i.MX7ULP bindings Anson Huang
@ 2019-08-22  2:37 ` Anson Huang
  2019-08-30 16:49   ` Guenter Roeck
  2019-08-22  2:37 ` [PATCH V4 3/4] ARM: imx_v6_v7_defconfig: Enable CONFIG_IMX7ULP_WDT by default Anson Huang
                   ` (3 subsequent siblings)
  4 siblings, 1 reply; 8+ messages in thread
From: Anson Huang @ 2019-08-22  2:37 UTC (permalink / raw)
  To: wim, linux, robh+dt, mark.rutland, shawnguo, s.hauer, kernel,
	festevam, linux, otavio, leonard.crestez, schnitzeltony,
	u.kleine-koenig, jan.tuerk, linux-watchdog, devicetree,
	linux-arm-kernel, linux-kernel
  Cc: Linux-imx

The i.MX7ULP Watchdog Timer (WDOG) module is an independent timer
that is available for system use.
It provides a safety feature to ensure that software is executing
as planned and that the CPU is not stuck in an infinite loop or
executing unintended code. If the WDOG module is not serviced
(refreshed) within a certain period, it resets the MCU.

Add driver support for i.MX7ULP watchdog.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
Changes since V3:
	- pass clk directly for reset action to avoid dereference from structure;
	- use constant instead of variable for wdog clock rate, as it is fixed as 1KHz.
---
 drivers/watchdog/Kconfig       |  13 +++
 drivers/watchdog/Makefile      |   1 +
 drivers/watchdog/imx7ulp_wdt.c | 243 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 257 insertions(+)
 create mode 100644 drivers/watchdog/imx7ulp_wdt.c

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index a8f5c81..d68e5b5 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -724,6 +724,19 @@ config IMX_SC_WDT
 	  To compile this driver as a module, choose M here: the
 	  module will be called imx_sc_wdt.
 
+config IMX7ULP_WDT
+	tristate "IMX7ULP Watchdog"
+	depends on ARCH_MXC || COMPILE_TEST
+	select WATCHDOG_CORE
+	help
+	  This is the driver for the hardware watchdog on the Freescale
+	  IMX7ULP and later processors. 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 imx7ulp_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 b5a0aed..2ee352b 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -67,6 +67,7 @@ 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-$(CONFIG_IMX7ULP_WDT) += imx7ulp_wdt.o
 obj-$(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/imx7ulp_wdt.c b/drivers/watchdog/imx7ulp_wdt.c
new file mode 100644
index 0000000..5ce5102
--- /dev/null
+++ b/drivers/watchdog/imx7ulp_wdt.c
@@ -0,0 +1,243 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 NXP.
+ */
+
+#include <linux/clk.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+#include <linux/watchdog.h>
+
+#define WDOG_CS			0x0
+#define WDOG_CS_CMD32EN		BIT(13)
+#define WDOG_CS_ULK		BIT(11)
+#define WDOG_CS_RCS		BIT(10)
+#define WDOG_CS_EN		BIT(7)
+#define WDOG_CS_UPDATE		BIT(5)
+
+#define WDOG_CNT	0x4
+#define WDOG_TOVAL	0x8
+
+#define REFRESH_SEQ0	0xA602
+#define REFRESH_SEQ1	0xB480
+#define REFRESH		((REFRESH_SEQ1 << 16) | REFRESH_SEQ0)
+
+#define UNLOCK_SEQ0	0xC520
+#define UNLOCK_SEQ1	0xD928
+#define UNLOCK		((UNLOCK_SEQ1 << 16) | UNLOCK_SEQ0)
+
+#define DEFAULT_TIMEOUT	60
+#define MAX_TIMEOUT	128
+#define WDOG_CLOCK_RATE	1000
+
+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) ")");
+
+struct imx7ulp_wdt_device {
+	struct notifier_block restart_handler;
+	struct watchdog_device wdd;
+	void __iomem *base;
+	struct clk *clk;
+};
+
+static inline void imx7ulp_wdt_enable(void __iomem *base, bool enable)
+{
+	u32 val = readl(base + WDOG_CS);
+
+	writel(UNLOCK, base + WDOG_CNT);
+	if (enable)
+		writel(val | WDOG_CS_EN, base + WDOG_CS);
+	else
+		writel(val & ~WDOG_CS_EN, base + WDOG_CS);
+}
+
+static inline bool imx7ulp_wdt_is_enabled(void __iomem *base)
+{
+	u32 val = readl(base + WDOG_CS);
+
+	return val & WDOG_CS_EN;
+}
+
+static int imx7ulp_wdt_ping(struct watchdog_device *wdog)
+{
+	struct imx7ulp_wdt_device *wdt = watchdog_get_drvdata(wdog);
+
+	writel(REFRESH, wdt->base + WDOG_CNT);
+
+	return 0;
+}
+
+static int imx7ulp_wdt_start(struct watchdog_device *wdog)
+{
+	struct imx7ulp_wdt_device *wdt = watchdog_get_drvdata(wdog);
+
+	imx7ulp_wdt_enable(wdt->base, true);
+
+	return 0;
+}
+
+static int imx7ulp_wdt_stop(struct watchdog_device *wdog)
+{
+	struct imx7ulp_wdt_device *wdt = watchdog_get_drvdata(wdog);
+
+	imx7ulp_wdt_enable(wdt->base, false);
+
+	return 0;
+}
+
+static int imx7ulp_wdt_set_timeout(struct watchdog_device *wdog,
+				   unsigned int timeout)
+{
+	struct imx7ulp_wdt_device *wdt = watchdog_get_drvdata(wdog);
+	u32 val = WDOG_CLOCK_RATE * timeout;
+
+	writel(UNLOCK, wdt->base + WDOG_CNT);
+	writel(val, wdt->base + WDOG_TOVAL);
+
+	wdog->timeout = timeout;
+
+	return 0;
+}
+
+static const struct watchdog_ops imx7ulp_wdt_ops = {
+	.owner = THIS_MODULE,
+	.start = imx7ulp_wdt_start,
+	.stop  = imx7ulp_wdt_stop,
+	.ping  = imx7ulp_wdt_ping,
+	.set_timeout = imx7ulp_wdt_set_timeout,
+};
+
+static const struct watchdog_info imx7ulp_wdt_info = {
+	.identity = "i.MX7ULP watchdog timer",
+	.options  = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING |
+		    WDIOF_MAGICCLOSE,
+};
+
+static inline void imx7ulp_wdt_init(void __iomem *base, unsigned int timeout)
+{
+	u32 val;
+
+	/* unlock the wdog for reconfiguration */
+	writel_relaxed(UNLOCK_SEQ0, base + WDOG_CNT);
+	writel_relaxed(UNLOCK_SEQ1, base + WDOG_CNT);
+
+	/* set an initial timeout value in TOVAL */
+	writel(timeout, base + WDOG_TOVAL);
+	/* enable 32bit command sequence and reconfigure */
+	val = BIT(13) | BIT(8) | BIT(5);
+	writel(val, base + WDOG_CS);
+}
+
+static void imx7ulp_wdt_action(void *data)
+{
+	clk_disable_unprepare(data);
+}
+
+static int imx7ulp_wdt_probe(struct platform_device *pdev)
+{
+	struct imx7ulp_wdt_device *imx7ulp_wdt;
+	struct device *dev = &pdev->dev;
+	struct watchdog_device *wdog;
+	int ret;
+
+	imx7ulp_wdt = devm_kzalloc(dev, sizeof(*imx7ulp_wdt), GFP_KERNEL);
+	if (!imx7ulp_wdt)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, imx7ulp_wdt);
+
+	imx7ulp_wdt->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(imx7ulp_wdt->base))
+		return PTR_ERR(imx7ulp_wdt->base);
+
+	imx7ulp_wdt->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(imx7ulp_wdt->clk)) {
+		dev_err(dev, "Failed to get watchdog clock\n");
+		return PTR_ERR(imx7ulp_wdt->clk);
+	}
+
+	ret = clk_prepare_enable(imx7ulp_wdt->clk);
+	if (ret)
+		return ret;
+
+	ret = devm_add_action_or_reset(dev, imx7ulp_wdt_action, imx7ulp_wdt->clk);
+	if (ret)
+		return ret;
+
+	wdog = &imx7ulp_wdt->wdd;
+	wdog->info = &imx7ulp_wdt_info;
+	wdog->ops = &imx7ulp_wdt_ops;
+	wdog->min_timeout = 1;
+	wdog->max_timeout = MAX_TIMEOUT;
+	wdog->parent = dev;
+	wdog->timeout = DEFAULT_TIMEOUT;
+
+	watchdog_init_timeout(wdog, 0, dev);
+	watchdog_stop_on_reboot(wdog);
+	watchdog_stop_on_unregister(wdog);
+	watchdog_set_drvdata(wdog, imx7ulp_wdt);
+	imx7ulp_wdt_init(imx7ulp_wdt->base, wdog->timeout * WDOG_CLOCK_RATE);
+
+	return devm_watchdog_register_device(dev, wdog);
+}
+
+static int __maybe_unused imx7ulp_wdt_suspend(struct device *dev)
+{
+	struct imx7ulp_wdt_device *imx7ulp_wdt = dev_get_drvdata(dev);
+
+	if (watchdog_active(&imx7ulp_wdt->wdd))
+		imx7ulp_wdt_stop(&imx7ulp_wdt->wdd);
+
+	clk_disable_unprepare(imx7ulp_wdt->clk);
+
+	return 0;
+}
+
+static int __maybe_unused imx7ulp_wdt_resume(struct device *dev)
+{
+	struct imx7ulp_wdt_device *imx7ulp_wdt = dev_get_drvdata(dev);
+	u32 timeout = imx7ulp_wdt->wdd.timeout * WDOG_CLOCK_RATE;
+	int ret;
+
+	ret = clk_prepare_enable(imx7ulp_wdt->clk);
+	if (ret)
+		return ret;
+
+	if (imx7ulp_wdt_is_enabled(imx7ulp_wdt->base))
+		imx7ulp_wdt_init(imx7ulp_wdt->base, timeout);
+
+	if (watchdog_active(&imx7ulp_wdt->wdd))
+		imx7ulp_wdt_start(&imx7ulp_wdt->wdd);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(imx7ulp_wdt_pm_ops, imx7ulp_wdt_suspend,
+			 imx7ulp_wdt_resume);
+
+static const struct of_device_id imx7ulp_wdt_dt_ids[] = {
+	{ .compatible = "fsl,imx7ulp-wdt", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx7ulp_wdt_dt_ids);
+
+static struct platform_driver imx7ulp_wdt_driver = {
+	.probe		= imx7ulp_wdt_probe,
+	.driver		= {
+		.name	= "imx7ulp-wdt",
+		.pm	= &imx7ulp_wdt_pm_ops,
+		.of_match_table = imx7ulp_wdt_dt_ids,
+	},
+};
+module_platform_driver(imx7ulp_wdt_driver);
+
+MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
+MODULE_DESCRIPTION("Freescale i.MX7ULP watchdog driver");
+MODULE_LICENSE("GPL v2");
-- 
2.7.4


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH V4 3/4] ARM: imx_v6_v7_defconfig: Enable CONFIG_IMX7ULP_WDT by default
  2019-08-22  2:37 [PATCH V4 1/4] dt-bindings: watchdog: Add i.MX7ULP bindings Anson Huang
  2019-08-22  2:37 ` [PATCH V4 2/4] watchdog: Add i.MX7ULP watchdog support Anson Huang
@ 2019-08-22  2:37 ` Anson Huang
  2019-09-11  6:24   ` Shawn Guo
  2019-08-22  2:37 ` [PATCH V4 4/4] ARM: dts: imx7ulp: Add wdog1 node Anson Huang
                   ` (2 subsequent siblings)
  4 siblings, 1 reply; 8+ messages in thread
From: Anson Huang @ 2019-08-22  2:37 UTC (permalink / raw)
  To: wim, linux, robh+dt, mark.rutland, shawnguo, s.hauer, kernel,
	festevam, linux, otavio, leonard.crestez, schnitzeltony,
	u.kleine-koenig, jan.tuerk, linux-watchdog, devicetree,
	linux-arm-kernel, linux-kernel
  Cc: Linux-imx

Select CONFIG_IMX7ULP_WDT by default to support i.MX7ULP watchdog.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
No changes.
---
 arch/arm/configs/imx_v6_v7_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/configs/imx_v6_v7_defconfig b/arch/arm/configs/imx_v6_v7_defconfig
index 9bfffbe..be2a694 100644
--- a/arch/arm/configs/imx_v6_v7_defconfig
+++ b/arch/arm/configs/imx_v6_v7_defconfig
@@ -236,6 +236,7 @@ CONFIG_DA9062_WATCHDOG=y
 CONFIG_DA9063_WATCHDOG=m
 CONFIG_RN5T618_WATCHDOG=y
 CONFIG_IMX2_WDT=y
+CONFIG_IMX7ULP_WDT=y
 CONFIG_MFD_DA9052_I2C=y
 CONFIG_MFD_DA9062=y
 CONFIG_MFD_DA9063=y
-- 
2.7.4


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH V4 4/4] ARM: dts: imx7ulp: Add wdog1 node
  2019-08-22  2:37 [PATCH V4 1/4] dt-bindings: watchdog: Add i.MX7ULP bindings Anson Huang
  2019-08-22  2:37 ` [PATCH V4 2/4] watchdog: Add i.MX7ULP watchdog support Anson Huang
  2019-08-22  2:37 ` [PATCH V4 3/4] ARM: imx_v6_v7_defconfig: Enable CONFIG_IMX7ULP_WDT by default Anson Huang
@ 2019-08-22  2:37 ` Anson Huang
  2019-08-27 20:08 ` [PATCH V4 1/4] dt-bindings: watchdog: Add i.MX7ULP bindings Rob Herring
  2019-08-30 16:50 ` Guenter Roeck
  4 siblings, 0 replies; 8+ messages in thread
From: Anson Huang @ 2019-08-22  2:37 UTC (permalink / raw)
  To: wim, linux, robh+dt, mark.rutland, shawnguo, s.hauer, kernel,
	festevam, linux, otavio, leonard.crestez, schnitzeltony,
	u.kleine-koenig, jan.tuerk, linux-watchdog, devicetree,
	linux-arm-kernel, linux-kernel
  Cc: Linux-imx

Add wdog1 node to support watchdog driver.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
No changes.
---
 arch/arm/boot/dts/imx7ulp.dtsi | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/arm/boot/dts/imx7ulp.dtsi b/arch/arm/boot/dts/imx7ulp.dtsi
index 6859a3a..1fdb5a35 100644
--- a/arch/arm/boot/dts/imx7ulp.dtsi
+++ b/arch/arm/boot/dts/imx7ulp.dtsi
@@ -264,6 +264,16 @@
 			#clock-cells = <1>;
 		};
 
+		wdog1: wdog@403d0000 {
+			compatible = "fsl,imx7ulp-wdt";
+			reg = <0x403d0000 0x10000>;
+			interrupts = <GIC_SPI 55 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&pcc2 IMX7ULP_CLK_WDG1>;
+			assigned-clocks = <&pcc2 IMX7ULP_CLK_WDG1>;
+			assigned-clocks-parents = <&scg1 IMX7ULP_CLK_FIRC_BUS_CLK>;
+			timeout-sec = <40>;
+		};
+
 		pcc2: clock-controller@403f0000 {
 			compatible = "fsl,imx7ulp-pcc2";
 			reg = <0x403f0000 0x10000>;
-- 
2.7.4


^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH V4 1/4] dt-bindings: watchdog: Add i.MX7ULP bindings
  2019-08-22  2:37 [PATCH V4 1/4] dt-bindings: watchdog: Add i.MX7ULP bindings Anson Huang
                   ` (2 preceding siblings ...)
  2019-08-22  2:37 ` [PATCH V4 4/4] ARM: dts: imx7ulp: Add wdog1 node Anson Huang
@ 2019-08-27 20:08 ` Rob Herring
  2019-08-30 16:50 ` Guenter Roeck
  4 siblings, 0 replies; 8+ messages in thread
From: Rob Herring @ 2019-08-27 20:08 UTC (permalink / raw)
  To: Anson Huang
  Cc: wim, linux, mark.rutland, shawnguo, s.hauer, kernel, festevam,
	linux, otavio, leonard.crestez, schnitzeltony, u.kleine-koenig,
	jan.tuerk, linux-watchdog, devicetree, linux-arm-kernel,
	linux-kernel, Linux-imx

On Wed, Aug 21, 2019 at 10:37:40PM -0400, Anson Huang wrote:
> Add the watchdog bindings for Freescale i.MX7ULP.
> 
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> ---
> No changes.
> ---
>  .../bindings/watchdog/fsl-imx7ulp-wdt.txt          | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/watchdog/fsl-imx7ulp-wdt.txt
> 
> diff --git a/Documentation/devicetree/bindings/watchdog/fsl-imx7ulp-wdt.txt b/Documentation/devicetree/bindings/watchdog/fsl-imx7ulp-wdt.txt
> new file mode 100644
> index 0000000..d83fc5c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/watchdog/fsl-imx7ulp-wdt.txt
> @@ -0,0 +1,22 @@
> +* Freescale i.MX7ULP Watchdog Timer (WDT) Controller
> +
> +Required properties:
> +- compatible : Should be "fsl,imx7ulp-wdt"
> +- reg : Should contain WDT registers location and length
> +- interrupts : Should contain WDT interrupt
> +- clocks: Should contain a phandle pointing to the gated peripheral clock.
> +
> +Optional properties:
> +- timeout-sec : Contains the watchdog timeout in seconds
> +
> +Examples:
> +
> +wdog1: wdog@403d0000 {

watchdog@...

With that,

Reviewed-by: Rob Herring <rohb@kernel.org>

> +	compatible = "fsl,imx7ulp-wdt";
> +	reg = <0x403d0000 0x10000>;
> +	interrupts = <GIC_SPI 55 IRQ_TYPE_LEVEL_HIGH>;
> +	clocks = <&pcc2 IMX7ULP_CLK_WDG1>;
> +	assigned-clocks = <&pcc2 IMX7ULP_CLK_WDG1>;
> +	assigned-clocks-parents = <&scg1 IMX7ULP_CLK_FIRC_BUS_CLK>;
> +	timeout-sec = <40>;
> +};
> -- 
> 2.7.4
> 

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH V4 2/4] watchdog: Add i.MX7ULP watchdog support
  2019-08-22  2:37 ` [PATCH V4 2/4] watchdog: Add i.MX7ULP watchdog support Anson Huang
@ 2019-08-30 16:49   ` Guenter Roeck
  0 siblings, 0 replies; 8+ messages in thread
From: Guenter Roeck @ 2019-08-30 16:49 UTC (permalink / raw)
  To: Anson Huang
  Cc: wim, robh+dt, mark.rutland, shawnguo, s.hauer, kernel, festevam,
	linux, otavio, leonard.crestez, schnitzeltony, u.kleine-koenig,
	jan.tuerk, linux-watchdog, devicetree, linux-arm-kernel,
	linux-kernel, Linux-imx

On Wed, Aug 21, 2019 at 10:37:41PM -0400, Anson Huang wrote:
> The i.MX7ULP Watchdog Timer (WDOG) module is an independent timer
> that is available for system use.
> It provides a safety feature to ensure that software is executing
> as planned and that the CPU is not stuck in an infinite loop or
> executing unintended code. If the WDOG module is not serviced
> (refreshed) within a certain period, it resets the MCU.
> 
> Add driver support for i.MX7ULP watchdog.
> 
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
> Changes since V3:
> 	- pass clk directly for reset action to avoid dereference from structure;
> 	- use constant instead of variable for wdog clock rate, as it is fixed as 1KHz.
> ---
>  drivers/watchdog/Kconfig       |  13 +++
>  drivers/watchdog/Makefile      |   1 +
>  drivers/watchdog/imx7ulp_wdt.c | 243 +++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 257 insertions(+)
>  create mode 100644 drivers/watchdog/imx7ulp_wdt.c
> 
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index a8f5c81..d68e5b5 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -724,6 +724,19 @@ config IMX_SC_WDT
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called imx_sc_wdt.
>  
> +config IMX7ULP_WDT
> +	tristate "IMX7ULP Watchdog"
> +	depends on ARCH_MXC || COMPILE_TEST
> +	select WATCHDOG_CORE
> +	help
> +	  This is the driver for the hardware watchdog on the Freescale
> +	  IMX7ULP and later processors. 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 imx7ulp_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 b5a0aed..2ee352b 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -67,6 +67,7 @@ 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-$(CONFIG_IMX7ULP_WDT) += imx7ulp_wdt.o
>  obj-$(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/imx7ulp_wdt.c b/drivers/watchdog/imx7ulp_wdt.c
> new file mode 100644
> index 0000000..5ce5102
> --- /dev/null
> +++ b/drivers/watchdog/imx7ulp_wdt.c
> @@ -0,0 +1,243 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright 2019 NXP.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/init.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/reboot.h>
> +#include <linux/watchdog.h>
> +
> +#define WDOG_CS			0x0
> +#define WDOG_CS_CMD32EN		BIT(13)
> +#define WDOG_CS_ULK		BIT(11)
> +#define WDOG_CS_RCS		BIT(10)
> +#define WDOG_CS_EN		BIT(7)
> +#define WDOG_CS_UPDATE		BIT(5)
> +
> +#define WDOG_CNT	0x4
> +#define WDOG_TOVAL	0x8
> +
> +#define REFRESH_SEQ0	0xA602
> +#define REFRESH_SEQ1	0xB480
> +#define REFRESH		((REFRESH_SEQ1 << 16) | REFRESH_SEQ0)
> +
> +#define UNLOCK_SEQ0	0xC520
> +#define UNLOCK_SEQ1	0xD928
> +#define UNLOCK		((UNLOCK_SEQ1 << 16) | UNLOCK_SEQ0)
> +
> +#define DEFAULT_TIMEOUT	60
> +#define MAX_TIMEOUT	128
> +#define WDOG_CLOCK_RATE	1000
> +
> +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) ")");
> +
> +struct imx7ulp_wdt_device {
> +	struct notifier_block restart_handler;
> +	struct watchdog_device wdd;
> +	void __iomem *base;
> +	struct clk *clk;
> +};
> +
> +static inline void imx7ulp_wdt_enable(void __iomem *base, bool enable)
> +{
> +	u32 val = readl(base + WDOG_CS);
> +
> +	writel(UNLOCK, base + WDOG_CNT);
> +	if (enable)
> +		writel(val | WDOG_CS_EN, base + WDOG_CS);
> +	else
> +		writel(val & ~WDOG_CS_EN, base + WDOG_CS);
> +}
> +
> +static inline bool imx7ulp_wdt_is_enabled(void __iomem *base)
> +{
> +	u32 val = readl(base + WDOG_CS);
> +
> +	return val & WDOG_CS_EN;
> +}
> +
> +static int imx7ulp_wdt_ping(struct watchdog_device *wdog)
> +{
> +	struct imx7ulp_wdt_device *wdt = watchdog_get_drvdata(wdog);
> +
> +	writel(REFRESH, wdt->base + WDOG_CNT);
> +
> +	return 0;
> +}
> +
> +static int imx7ulp_wdt_start(struct watchdog_device *wdog)
> +{
> +	struct imx7ulp_wdt_device *wdt = watchdog_get_drvdata(wdog);
> +
> +	imx7ulp_wdt_enable(wdt->base, true);
> +
> +	return 0;
> +}
> +
> +static int imx7ulp_wdt_stop(struct watchdog_device *wdog)
> +{
> +	struct imx7ulp_wdt_device *wdt = watchdog_get_drvdata(wdog);
> +
> +	imx7ulp_wdt_enable(wdt->base, false);
> +
> +	return 0;
> +}
> +
> +static int imx7ulp_wdt_set_timeout(struct watchdog_device *wdog,
> +				   unsigned int timeout)
> +{
> +	struct imx7ulp_wdt_device *wdt = watchdog_get_drvdata(wdog);
> +	u32 val = WDOG_CLOCK_RATE * timeout;
> +
> +	writel(UNLOCK, wdt->base + WDOG_CNT);
> +	writel(val, wdt->base + WDOG_TOVAL);
> +
> +	wdog->timeout = timeout;
> +
> +	return 0;
> +}
> +
> +static const struct watchdog_ops imx7ulp_wdt_ops = {
> +	.owner = THIS_MODULE,
> +	.start = imx7ulp_wdt_start,
> +	.stop  = imx7ulp_wdt_stop,
> +	.ping  = imx7ulp_wdt_ping,
> +	.set_timeout = imx7ulp_wdt_set_timeout,
> +};
> +
> +static const struct watchdog_info imx7ulp_wdt_info = {
> +	.identity = "i.MX7ULP watchdog timer",
> +	.options  = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING |
> +		    WDIOF_MAGICCLOSE,
> +};
> +
> +static inline void imx7ulp_wdt_init(void __iomem *base, unsigned int timeout)
> +{
> +	u32 val;
> +
> +	/* unlock the wdog for reconfiguration */
> +	writel_relaxed(UNLOCK_SEQ0, base + WDOG_CNT);
> +	writel_relaxed(UNLOCK_SEQ1, base + WDOG_CNT);
> +
> +	/* set an initial timeout value in TOVAL */
> +	writel(timeout, base + WDOG_TOVAL);
> +	/* enable 32bit command sequence and reconfigure */
> +	val = BIT(13) | BIT(8) | BIT(5);
> +	writel(val, base + WDOG_CS);
> +}
> +
> +static void imx7ulp_wdt_action(void *data)
> +{
> +	clk_disable_unprepare(data);
> +}
> +
> +static int imx7ulp_wdt_probe(struct platform_device *pdev)
> +{
> +	struct imx7ulp_wdt_device *imx7ulp_wdt;
> +	struct device *dev = &pdev->dev;
> +	struct watchdog_device *wdog;
> +	int ret;
> +
> +	imx7ulp_wdt = devm_kzalloc(dev, sizeof(*imx7ulp_wdt), GFP_KERNEL);
> +	if (!imx7ulp_wdt)
> +		return -ENOMEM;
> +
> +	platform_set_drvdata(pdev, imx7ulp_wdt);
> +
> +	imx7ulp_wdt->base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(imx7ulp_wdt->base))
> +		return PTR_ERR(imx7ulp_wdt->base);
> +
> +	imx7ulp_wdt->clk = devm_clk_get(dev, NULL);
> +	if (IS_ERR(imx7ulp_wdt->clk)) {
> +		dev_err(dev, "Failed to get watchdog clock\n");
> +		return PTR_ERR(imx7ulp_wdt->clk);
> +	}
> +
> +	ret = clk_prepare_enable(imx7ulp_wdt->clk);
> +	if (ret)
> +		return ret;
> +
> +	ret = devm_add_action_or_reset(dev, imx7ulp_wdt_action, imx7ulp_wdt->clk);
> +	if (ret)
> +		return ret;
> +
> +	wdog = &imx7ulp_wdt->wdd;
> +	wdog->info = &imx7ulp_wdt_info;
> +	wdog->ops = &imx7ulp_wdt_ops;
> +	wdog->min_timeout = 1;
> +	wdog->max_timeout = MAX_TIMEOUT;
> +	wdog->parent = dev;
> +	wdog->timeout = DEFAULT_TIMEOUT;
> +
> +	watchdog_init_timeout(wdog, 0, dev);
> +	watchdog_stop_on_reboot(wdog);
> +	watchdog_stop_on_unregister(wdog);
> +	watchdog_set_drvdata(wdog, imx7ulp_wdt);
> +	imx7ulp_wdt_init(imx7ulp_wdt->base, wdog->timeout * WDOG_CLOCK_RATE);
> +
> +	return devm_watchdog_register_device(dev, wdog);
> +}
> +
> +static int __maybe_unused imx7ulp_wdt_suspend(struct device *dev)
> +{
> +	struct imx7ulp_wdt_device *imx7ulp_wdt = dev_get_drvdata(dev);
> +
> +	if (watchdog_active(&imx7ulp_wdt->wdd))
> +		imx7ulp_wdt_stop(&imx7ulp_wdt->wdd);
> +
> +	clk_disable_unprepare(imx7ulp_wdt->clk);
> +
> +	return 0;
> +}
> +
> +static int __maybe_unused imx7ulp_wdt_resume(struct device *dev)
> +{
> +	struct imx7ulp_wdt_device *imx7ulp_wdt = dev_get_drvdata(dev);
> +	u32 timeout = imx7ulp_wdt->wdd.timeout * WDOG_CLOCK_RATE;
> +	int ret;
> +
> +	ret = clk_prepare_enable(imx7ulp_wdt->clk);
> +	if (ret)
> +		return ret;
> +
> +	if (imx7ulp_wdt_is_enabled(imx7ulp_wdt->base))
> +		imx7ulp_wdt_init(imx7ulp_wdt->base, timeout);
> +
> +	if (watchdog_active(&imx7ulp_wdt->wdd))
> +		imx7ulp_wdt_start(&imx7ulp_wdt->wdd);
> +
> +	return 0;
> +}
> +
> +static SIMPLE_DEV_PM_OPS(imx7ulp_wdt_pm_ops, imx7ulp_wdt_suspend,
> +			 imx7ulp_wdt_resume);
> +
> +static const struct of_device_id imx7ulp_wdt_dt_ids[] = {
> +	{ .compatible = "fsl,imx7ulp-wdt", },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, imx7ulp_wdt_dt_ids);
> +
> +static struct platform_driver imx7ulp_wdt_driver = {
> +	.probe		= imx7ulp_wdt_probe,
> +	.driver		= {
> +		.name	= "imx7ulp-wdt",
> +		.pm	= &imx7ulp_wdt_pm_ops,
> +		.of_match_table = imx7ulp_wdt_dt_ids,
> +	},
> +};
> +module_platform_driver(imx7ulp_wdt_driver);
> +
> +MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
> +MODULE_DESCRIPTION("Freescale i.MX7ULP watchdog driver");
> +MODULE_LICENSE("GPL v2");
> -- 
> 2.7.4
> 

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH V4 1/4] dt-bindings: watchdog: Add i.MX7ULP bindings
  2019-08-22  2:37 [PATCH V4 1/4] dt-bindings: watchdog: Add i.MX7ULP bindings Anson Huang
                   ` (3 preceding siblings ...)
  2019-08-27 20:08 ` [PATCH V4 1/4] dt-bindings: watchdog: Add i.MX7ULP bindings Rob Herring
@ 2019-08-30 16:50 ` Guenter Roeck
  4 siblings, 0 replies; 8+ messages in thread
From: Guenter Roeck @ 2019-08-30 16:50 UTC (permalink / raw)
  To: Anson Huang
  Cc: wim, robh+dt, mark.rutland, shawnguo, s.hauer, kernel, festevam,
	linux, otavio, leonard.crestez, schnitzeltony, u.kleine-koenig,
	jan.tuerk, linux-watchdog, devicetree, linux-arm-kernel,
	linux-kernel, Linux-imx

On Wed, Aug 21, 2019 at 10:37:40PM -0400, Anson Huang wrote:
> Add the watchdog bindings for Freescale i.MX7ULP.
> 
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>

With the change requested by Rob:

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
> No changes.
> ---
>  .../bindings/watchdog/fsl-imx7ulp-wdt.txt          | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/watchdog/fsl-imx7ulp-wdt.txt
> 
> diff --git a/Documentation/devicetree/bindings/watchdog/fsl-imx7ulp-wdt.txt b/Documentation/devicetree/bindings/watchdog/fsl-imx7ulp-wdt.txt
> new file mode 100644
> index 0000000..d83fc5c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/watchdog/fsl-imx7ulp-wdt.txt
> @@ -0,0 +1,22 @@
> +* Freescale i.MX7ULP Watchdog Timer (WDT) Controller
> +
> +Required properties:
> +- compatible : Should be "fsl,imx7ulp-wdt"
> +- reg : Should contain WDT registers location and length
> +- interrupts : Should contain WDT interrupt
> +- clocks: Should contain a phandle pointing to the gated peripheral clock.
> +
> +Optional properties:
> +- timeout-sec : Contains the watchdog timeout in seconds
> +
> +Examples:
> +
> +wdog1: wdog@403d0000 {
> +	compatible = "fsl,imx7ulp-wdt";
> +	reg = <0x403d0000 0x10000>;
> +	interrupts = <GIC_SPI 55 IRQ_TYPE_LEVEL_HIGH>;
> +	clocks = <&pcc2 IMX7ULP_CLK_WDG1>;
> +	assigned-clocks = <&pcc2 IMX7ULP_CLK_WDG1>;
> +	assigned-clocks-parents = <&scg1 IMX7ULP_CLK_FIRC_BUS_CLK>;
> +	timeout-sec = <40>;
> +};
> -- 
> 2.7.4
> 

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH V4 3/4] ARM: imx_v6_v7_defconfig: Enable CONFIG_IMX7ULP_WDT by default
  2019-08-22  2:37 ` [PATCH V4 3/4] ARM: imx_v6_v7_defconfig: Enable CONFIG_IMX7ULP_WDT by default Anson Huang
@ 2019-09-11  6:24   ` Shawn Guo
  0 siblings, 0 replies; 8+ messages in thread
From: Shawn Guo @ 2019-09-11  6:24 UTC (permalink / raw)
  To: Anson Huang
  Cc: wim, linux, robh+dt, mark.rutland, s.hauer, kernel, festevam,
	linux, otavio, leonard.crestez, schnitzeltony, u.kleine-koenig,
	jan.tuerk, linux-watchdog, devicetree, linux-arm-kernel,
	linux-kernel, Linux-imx

On Wed, Aug 21, 2019 at 10:37:42PM -0400, Anson Huang wrote:
> Select CONFIG_IMX7ULP_WDT by default to support i.MX7ULP watchdog.
> 
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>

Patch #4 and #5 look good to me, and I will pick them up once the first
3 get applied by Guenter.

Shawn

^ permalink raw reply	[flat|nested] 8+ messages in thread

end of thread, back to index

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-08-22  2:37 [PATCH V4 1/4] dt-bindings: watchdog: Add i.MX7ULP bindings Anson Huang
2019-08-22  2:37 ` [PATCH V4 2/4] watchdog: Add i.MX7ULP watchdog support Anson Huang
2019-08-30 16:49   ` Guenter Roeck
2019-08-22  2:37 ` [PATCH V4 3/4] ARM: imx_v6_v7_defconfig: Enable CONFIG_IMX7ULP_WDT by default Anson Huang
2019-09-11  6:24   ` Shawn Guo
2019-08-22  2:37 ` [PATCH V4 4/4] ARM: dts: imx7ulp: Add wdog1 node Anson Huang
2019-08-27 20:08 ` [PATCH V4 1/4] dt-bindings: watchdog: Add i.MX7ULP bindings Rob Herring
2019-08-30 16:50 ` Guenter Roeck

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