[RESEND] [PATCH V3 0/2] Add watchdog DT nodes and use syscon regmap interface to configure pmu registers

[RESEND] [PATCH V3 0/2] Add watchdog DT nodes and use syscon regmap interface to configure pmu registers

[Leela Krishna Amudala]

This patchset does the following things
	- Adds watchdog DT nodes to Exynos5250 and 5420
	- Uses syscon regmap interface to configure pmu registers
	  to mask/unmask enable/disable of watchdog.
	
This patch set is rebased on Kgene's for-next branch and tested on SMDK5420

Changes since V2:
	- used syscon regmap interface to configure pmu registers in WDT driver
	  (suggested by Tomasz Figa <t.figa@samsung.com>)

Changes since V1:
        - Added new compatible string for Exynos5 SoCs
        - Introduced quirk mechanism to program PMU registers
        - Addressed comments given by Tomasz Figa <t.figa@samsung.com>

Leela Krishna Amudala (2):
  ARM: dts: add watchdog device nodes for Exynos5250 and Exynos5420
  watchdog: s3c2410_wdt: use syscon regmap interface to configure pmu
    register

 .../devicetree/bindings/watchdog/samsung-wdt.txt   |   13 ++-
 arch/arm/boot/dts/exynos5.dtsi                     |   12 +--
 arch/arm/boot/dts/exynos5250.dtsi                  |    7 +-
 arch/arm/boot/dts/exynos5420.dtsi                  |   10 ++
 drivers/watchdog/s3c2410_wdt.c                     |  114 ++++++++++++++++++--
 5 files changed, 139 insertions(+), 17 deletions(-)

-- 
1.7.10.4

[RESEND] [PATCH V3 1/2] ARM: dts: add watchdog device nodes for Exynos5250 and Exynos5420

[Leela Krishna Amudala]

Adds watchdog device nodes to the DT device list for Exynos5250 and Exynos5420

Signed-off-by: Leela Krishna Amudala <l.krishna@samsung.com>
---
 arch/arm/boot/dts/exynos5.dtsi    |   12 +++++-------
 arch/arm/boot/dts/exynos5250.dtsi |    7 ++++++-
 arch/arm/boot/dts/exynos5420.dtsi |   10 ++++++++++
 3 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/arch/arm/boot/dts/exynos5.dtsi b/arch/arm/boot/dts/exynos5.dtsi
index e52b038..e7b6dbd 100644
--- a/arch/arm/boot/dts/exynos5.dtsi
+++ b/arch/arm/boot/dts/exynos5.dtsi
@@ -81,13 +81,6 @@
 		status = "disabled";
 	};
 
-	watchdog {
-		compatible = "samsung,s3c2410-wdt";
-		reg = <0x101D0000 0x100>;
-		interrupts = <0 42 0>;
-		status = "disabled";
-	};
-
 	fimd@14400000 {
 		compatible = "samsung,exynos5250-fimd";
 		interrupt-parent = <&combiner>;
@@ -106,4 +99,9 @@
 		#size-cells = <0>;
 		status = "disabled";
 	};
+
+	pmu_sys_reg: pmusysreg {
+		compatible = "samsung,exynos5-pmureg", "syscon";
+		reg = <0x10040000 0x5000>;
+	};
 };
diff --git a/arch/arm/boot/dts/exynos5250.dtsi b/arch/arm/boot/dts/exynos5250.dtsi
index c4a8662..3ccd150 100644
--- a/arch/arm/boot/dts/exynos5250.dtsi
+++ b/arch/arm/boot/dts/exynos5250.dtsi
@@ -158,9 +158,14 @@
 		interrupts = <0 47 0>;
 	};
 
-	watchdog {
+	watchdog@101D0000 {
+		compatible = "samsung,s3c5250-wdt";
+		reg = <0x101D0000 0x100>;
+		interrupts = <0 42 0>;
 		clocks = <&clock 336>;
 		clock-names = "watchdog";
+		samsung,sysreg = <&pmu_sys_reg>;
+		status = "okay";
 	};
 
 	g2d@10850000 {
diff --git a/arch/arm/boot/dts/exynos5420.dtsi b/arch/arm/boot/dts/exynos5420.dtsi
index 6ffefd1..5fb7ae2 100644
--- a/arch/arm/boot/dts/exynos5420.dtsi
+++ b/arch/arm/boot/dts/exynos5420.dtsi
@@ -369,4 +369,14 @@
 		clock-names = "gscl";
 		samsung,power-domain = <&gsc_pd>;
 	};
+
+        watchdog@101D0000 {
+		compatible = "samsung,s3c5420-wdt";
+		reg = <0x101D0000 0x100>;
+		interrupts = <0 42 0>;
+		clocks = <&clock 316>;
+		clock-names = "watchdog";
+		samsung,sysreg = <&pmu_sys_reg>;
+		status = "okay";
+        };
 };
-- 
1.7.10.4

[RESEND] [PATCH V3 2/2] watchdog: s3c2410_wdt: use syscon regmap interface to configure pmu register

[Leela Krishna Amudala]

The syscon regmap interface is used to configure AUTOMATIC_WDT_RESET_DISABLE
and MASK_WDT_RESET_REQUEST registers of PMU to mask/unmask enable/disable of
watchdog in probe and s2r scenarios.

Signed-off-by: Leela Krishna Amudala <l.krishna@samsung.com>
---
 .../devicetree/bindings/watchdog/samsung-wdt.txt   |   13 ++-
 drivers/watchdog/s3c2410_wdt.c                     |  114 ++++++++++++++++++--
 2 files changed, 118 insertions(+), 9 deletions(-)

diff --git a/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt b/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt
index 2aa486c..c46c7ce 100644
--- a/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt
+++ b/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt
@@ -5,10 +5,21 @@ after a preset amount of time during which the WDT reset event has not
 occurred.
 
 Required properties:
-- compatible : should be "samsung,s3c2410-wdt"
+- compatible : should be "samsung,s3c2410-wdt" or "samsung,s3c5250-wdt" or "samsung,s3c5420-wdt"
 - reg : base physical address of the controller and length of memory mapped
 	region.
 - interrupts : interrupt number to the cpu.
+- samsung,pmusysreg : reference node to pmu sysreg (required only in case of Exynos5250 and 5420)
 
 Optional properties:
 - timeout-sec : contains the watchdog timeout in seconds.
+
+watchdog@101D0000 {
+	compatible = "samsung,s3c5250-wdt";
+	reg = <0x101D0000 0x100>;
+	interrupts = <0 42 0>;
+	clocks = <&clock 336>;
+	clock-names = "watchdog";
+	samsung,sysreg = <&pmu_sys_reg>;
+	status = "okay";
+};
diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
index 23aad7c..2a3429c 100644
--- a/drivers/watchdog/s3c2410_wdt.c
+++ b/drivers/watchdog/s3c2410_wdt.c
@@ -41,6 +41,8 @@
 #include <linux/slab.h>
 #include <linux/err.h>
 #include <linux/of.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
 
 #define S3C2410_WTCON		0x00
 #define S3C2410_WTDAT		0x04
@@ -61,6 +63,10 @@
 #define CONFIG_S3C2410_WATCHDOG_ATBOOT		(0)
 #define CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME	(15)
 
+#define WDT_DISABLE_REG_OFFSET		0x0408
+#define WDT_MASK_RESET_REG_OFFSET	0x040c
+#define QUIRK_NEEDS_PMU_CONFIG		(1 << 0)
+
 static bool nowayout	= WATCHDOG_NOWAYOUT;
 static int tmr_margin;
 static int tmr_atboot	= CONFIG_S3C2410_WATCHDOG_ATBOOT;
@@ -84,6 +90,12 @@ MODULE_PARM_DESC(soft_noboot, "Watchdog action, set to 1 to ignore reboots, "
 			"0 to reboot (default 0)");
 MODULE_PARM_DESC(debug, "Watchdog debug, set to >1 for debug (default 0)");
 
+struct pmu_config {
+	int	disable_reg;
+	int	mask_reset_reg;
+	int	mask_bit;
+};
+
 struct s3c2410_wdt {
 	struct device		*dev;
 	struct clk		*clock;
@@ -94,7 +106,34 @@ struct s3c2410_wdt {
 	unsigned long		wtdat_save;
 	struct watchdog_device	wdt_device;
 	struct notifier_block	freq_transition;
+	struct pmu_config	*wdt_pmu_config;
+	struct regmap		*pmureg;
+	unsigned int		quirks;
+};
+
+static struct pmu_config pmu_config_5250  = {
+	.disable_reg = WDT_DISABLE_REG_OFFSET,
+	.mask_reset_reg = WDT_MASK_RESET_REG_OFFSET,
+	.mask_bit = 20
+};
+
+static struct pmu_config pmu_config_5420 = {
+	.disable_reg = WDT_DISABLE_REG_OFFSET,
+	.mask_reset_reg = WDT_MASK_RESET_REG_OFFSET,
+	.mask_bit = 0
+};
+
+#ifdef CONFIG_OF
+static const struct of_device_id s3c2410_wdt_match[] = {
+	{ .compatible = "samsung,s3c2410-wdt" },
+	{ .compatible = "samsung,s3c5250-wdt",
+	  .data = (struct pmu_config *) &pmu_config_5250 },
+	{ .compatible = "samsung,s3c5420-wdt",
+	  .data = (struct pmu_config *) &pmu_config_5420 },
+	{},
 };
+MODULE_DEVICE_TABLE(of, s3c2410_wdt_match);
+#endif
 
 /* watchdog control routines */
 
@@ -111,6 +150,40 @@ static inline struct s3c2410_wdt *freq_to_wdt(struct notifier_block *nb)
 	return container_of(nb, struct s3c2410_wdt, freq_transition);
 }
 
+static void s3c2410wdt_mask_and_disable_reset(int mask, struct s3c2410_wdt *wdt)
+{
+	unsigned int disable, mask_reset;
+	int ret;
+
+	ret = regmap_read(wdt->pmureg, wdt->wdt_pmu_config->disable_reg,
+								&disable);
+	if (ret < 0) {
+		dev_err(wdt->dev, "%s:%d fail to read disable reg(%d)\n",
+				__func__, __LINE__, ret);
+		return;
+	}
+
+	ret = regmap_read(wdt->pmureg, wdt->wdt_pmu_config->mask_reset_reg,
+								&mask_reset);
+	if (ret < 0) {
+		dev_err(wdt->dev, "%s:%d fail to read mask reset reg(%d)\n",
+				__func__, __LINE__, ret);
+		return;
+	}
+
+	if (mask) {
+		disable |= (1 << wdt->wdt_pmu_config->mask_bit);
+		mask_reset |= (1 << wdt->wdt_pmu_config->mask_bit);
+	} else {
+		disable &= ~(1 << wdt->wdt_pmu_config->mask_bit);
+		mask_reset &= ~(1 << wdt->wdt_pmu_config->mask_bit);
+	}
+
+	regmap_write(wdt->pmureg, wdt->wdt_pmu_config->disable_reg, disable);
+	regmap_write(wdt->pmureg, wdt->wdt_pmu_config->mask_reset_reg,
+								mask_reset);
+}
+
 static int s3c2410wdt_keepalive(struct watchdog_device *wdd)
 {
 	struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
@@ -332,6 +405,14 @@ static inline void s3c2410wdt_cpufreq_deregister(struct s3c2410_wdt *wdt)
 }
 #endif
 
+/* s3c2410_get_wdt_driver_data */
+static inline unsigned int get_wdt_driver_data(struct platform_device *pdev)
+{
+	const struct of_device_id *match;
+	match = of_match_node(s3c2410_wdt_match, pdev->dev.of_node);
+	return (unsigned int)match->data;
+}
+
 static int s3c2410wdt_probe(struct platform_device *pdev)
 {
 	struct device *dev;
@@ -354,6 +435,17 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
 	spin_lock_init(&wdt->lock);
 	wdt->wdt_device = s3c2410_wdd;
 
+	wdt->pmureg = syscon_regmap_lookup_by_phandle(dev->of_node,
+						"samsung,sysreg");
+	if (IS_ERR(wdt->pmureg)) {
+		dev_err(dev, "syscon regmap lookup failed.\n");
+		return PTR_ERR(wdt->pmureg);
+	}
+
+	wdt->wdt_pmu_config = (struct pmu_config *) get_wdt_driver_data(pdev);
+	if (wdt->wdt_pmu_config)
+		wdt->quirks = QUIRK_NEEDS_PMU_CONFIG;
+
 	wdt_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (wdt_irq == NULL) {
 		dev_err(dev, "no irq resource specified\n");
@@ -444,6 +536,8 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
 		 (wtcon & S3C2410_WTCON_RSTEN) ? "en" : "dis",
 		 (wtcon & S3C2410_WTCON_INTEN) ? "en" : "dis");
 
+	if (wdt->quirks & QUIRK_NEEDS_PMU_CONFIG)
+		s3c2410wdt_mask_and_disable_reset(0, wdt);
 	return 0;
 
  err_cpufreq:
@@ -461,6 +555,9 @@ static int s3c2410wdt_remove(struct platform_device *dev)
 {
 	struct s3c2410_wdt *wdt = platform_get_drvdata(dev);
 
+	if (wdt->quirks & QUIRK_NEEDS_PMU_CONFIG)
+		s3c2410wdt_mask_and_disable_reset(1, wdt);
+
 	watchdog_unregister_device(&wdt->wdt_device);
 
 	s3c2410wdt_cpufreq_deregister(wdt);
@@ -475,6 +572,9 @@ static void s3c2410wdt_shutdown(struct platform_device *dev)
 {
 	struct s3c2410_wdt *wdt = platform_get_drvdata(dev);
 
+	if (wdt->quirks & QUIRK_NEEDS_PMU_CONFIG)
+		s3c2410wdt_mask_and_disable_reset(1, wdt);
+
 	s3c2410wdt_stop(&wdt->wdt_device);
 }
 
@@ -488,6 +588,9 @@ static int s3c2410wdt_suspend(struct device *dev)
 	wdt->wtcon_save = readl(wdt->reg_base + S3C2410_WTCON);
 	wdt->wtdat_save = readl(wdt->reg_base + S3C2410_WTDAT);
 
+	if (wdt->quirks & QUIRK_NEEDS_PMU_CONFIG)
+		s3c2410wdt_mask_and_disable_reset(1, wdt);
+
 	/* Note that WTCNT doesn't need to be saved. */
 	s3c2410wdt_stop(&wdt->wdt_device);
 
@@ -503,6 +606,9 @@ static int s3c2410wdt_resume(struct device *dev)
 	writel(wdt->wtdat_save, wdt->reg_base + S3C2410_WTCNT);/* Reset count */
 	writel(wdt->wtcon_save, wdt->reg_base + S3C2410_WTCON);
 
+	if (wdt->quirks & QUIRK_NEEDS_PMU_CONFIG)
+		s3c2410wdt_mask_and_disable_reset(0, wdt);
+
 	dev_info(dev, "watchdog %sabled\n",
 		(wdt->wtcon_save & S3C2410_WTCON_ENABLE) ? "en" : "dis");
 
@@ -513,14 +619,6 @@ static int s3c2410wdt_resume(struct device *dev)
 static SIMPLE_DEV_PM_OPS(s3c2410wdt_pm_ops, s3c2410wdt_suspend,
 			s3c2410wdt_resume);
 
-#ifdef CONFIG_OF
-static const struct of_device_id s3c2410_wdt_match[] = {
-	{ .compatible = "samsung,s3c2410-wdt" },
-	{},
-};
-MODULE_DEVICE_TABLE(of, s3c2410_wdt_match);
-#endif
-
 static struct platform_driver s3c2410wdt_driver = {
 	.probe		= s3c2410wdt_probe,
 	.remove		= s3c2410wdt_remove,
-- 
1.7.10.4

Re: [RESEND] [PATCH V3 2/2] watchdog: s3c2410_wdt: use syscon regmap interface to configure pmu register

[Kumar Gala]

On Oct 30, 2013, at 2:01 AM, Leela Krishna Amudala wrote:

> The syscon regmap interface is used to configure AUTOMATIC_WDT_RESET_DISABLE
> and MASK_WDT_RESET_REQUEST registers of PMU to mask/unmask enable/disable of
> watchdog in probe and s2r scenarios.
> 
> Signed-off-by: Leela Krishna Amudala <l.krishna@samsung.com>
> ---
> .../devicetree/bindings/watchdog/samsung-wdt.txt   |   13 ++-
> drivers/watchdog/s3c2410_wdt.c                     |  114 ++++++++++++++++++--
> 2 files changed, 118 insertions(+), 9 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt b/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt
> index 2aa486c..c46c7ce 100644
> --- a/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt
> +++ b/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt
> @@ -5,10 +5,21 @@ after a preset amount of time during which the WDT reset event has not
> occurred.
> 
> Required properties:
> -- compatible : should be "samsung,s3c2410-wdt"
> +- compatible : should be "samsung,s3c2410-wdt" or "samsung,s3c5250-wdt" or "samsung,s3c5420-wdt"
> - reg : base physical address of the controller and length of memory mapped
> 	region.
> - interrupts : interrupt number to the cpu.
> +- samsung,pmusysreg : reference node to pmu sysreg (required only in case of Exynos5250 and 5420)

Rather than saying required only on Exynos5250 and 5420, how about saying required only in case of compatible being "samsung,s3c5250-wdt" or "samsung,s3c5420-wdt"

> 
> Optional properties:
> - timeout-sec : contains the watchdog timeout in seconds.
> +
> +watchdog@101D0000 {
> +	compatible = "samsung,s3c5250-wdt";
> +	reg = <0x101D0000 0x100>;
> +	interrupts = <0 42 0>;
> +	clocks = <&clock 336>;
> +	clock-names = "watchdog";
> +	samsung,sysreg = <&pmu_sys_reg>;
> +	status = "okay";
> +};

-- 
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