Commit f0d9d0f4 authored by Matthew McClintock's avatar Matthew McClintock Committed by Wim Van Sebroeck
Browse files

watchdog: qcom: add option for standalone watchdog not in timer block 



Commit 0dfd582e ("watchdog: qcom: use timer devicetree
binding") moved to use the watchdog as a subset timer
register block. Some devices have the watchdog completely
standalone with slightly different register offsets as
well so let's account for the differences here.

The existing "kpss-standalone" compatible string doesn't
make it entirely clear exactly what the device is so
rename to "kpss-wdt" to reflect watchdog timer
functionality. Also update ipq4019 DTS with an SoC
specific compatible.

Signed-off-by: default avatarMatthew McClintock <mmcclint@codeaurora.org>
Signed-off-by: default avatarThomas Pedersen <twp@codeaurora.org>
Reviewed-by: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarWim Van Sebroeck <wim@iguana.be>
parent 6e062696

Documentation/devicetree/bindings/watchdog/qcom-wdt.txt

+2 −0
Original line number Diff line number Diff line
@@ -7,8 +7,10 @@ Required properties : 
			"qcom,kpss-wdt-msm8960"

			"qcom,kpss-wdt-apq8064"

			"qcom,kpss-wdt-ipq8064"

			"qcom,kpss-wdt-ipq4019"

			"qcom,kpss-timer"

			"qcom,scss-timer"

			"qcom,kpss-wdt"



- reg : shall contain base register location and length

- clocks : shall contain the input clock

arch/arm/boot/dts/qcom-ipq4019.dtsi

+1 −1
Original line number Diff line number Diff line
@@ -252,7 +252,7 @@ 
		};



		watchdog@b017000 {

			compatible = "qcom,kpss-standalone";

			compatible = "qcom,kpss-wdt", "qcom,kpss-wdt-ipq4019";

			reg = <0xb017000 0x40>;

			clocks = <&sleep_clk>;

			timeout-sec = <10>;

drivers/watchdog/qcom-wdt.c

+48 −16
Original line number Diff line number Diff line
@@ -18,19 +18,42 @@ 
#include <linux/of.h>

#include <linux/platform_device.h>

#include <linux/watchdog.h>

#include <linux/of_device.h>



#define WDT_RST		0x38

#define WDT_EN		0x40

#define WDT_STS		0x44

#define WDT_BITE_TIME	0x5C

enum wdt_reg {

	WDT_RST,

	WDT_EN,

	WDT_STS,

	WDT_BITE_TIME,

};



static const u32 reg_offset_data_apcs_tmr[] = {

	[WDT_RST] = 0x38,

	[WDT_EN] = 0x40,

	[WDT_STS] = 0x44,

	[WDT_BITE_TIME] = 0x5C,

};



static const u32 reg_offset_data_kpss[] = {

	[WDT_RST] = 0x4,

	[WDT_EN] = 0x8,

	[WDT_STS] = 0xC,

	[WDT_BITE_TIME] = 0x14,

};



struct qcom_wdt {

	struct watchdog_device	wdd;

	struct clk		*clk;

	unsigned long		rate;

	void __iomem		*base;

	const u32		*layout;

};



static void __iomem *wdt_addr(struct qcom_wdt *wdt, enum wdt_reg reg)

{

	return wdt->base + wdt->layout[reg];

}



static inline

struct qcom_wdt *to_qcom_wdt(struct watchdog_device *wdd)

{
@@ -41,10 +64,10 @@ static int qcom_wdt_start(struct watchdog_device *wdd) 
{

	struct qcom_wdt *wdt = to_qcom_wdt(wdd);



	writel(0, wdt->base + WDT_EN);

	writel(1, wdt->base + WDT_RST);

	writel(wdd->timeout * wdt->rate, wdt->base + WDT_BITE_TIME);

	writel(1, wdt->base + WDT_EN);

	writel(0, wdt_addr(wdt, WDT_EN));

	writel(1, wdt_addr(wdt, WDT_RST));

	writel(wdd->timeout * wdt->rate, wdt_addr(wdt, WDT_BITE_TIME));

	writel(1, wdt_addr(wdt, WDT_EN));

	return 0;

}
@@ -52,7 +75,7 @@ static int qcom_wdt_stop(struct watchdog_device *wdd) 
{

	struct qcom_wdt *wdt = to_qcom_wdt(wdd);



	writel(0, wdt->base + WDT_EN);

	writel(0, wdt_addr(wdt, WDT_EN));

	return 0;

}
@@ -60,7 +83,7 @@ static int qcom_wdt_ping(struct watchdog_device *wdd) 
{

	struct qcom_wdt *wdt = to_qcom_wdt(wdd);



	writel(1, wdt->base + WDT_RST);

	writel(1, wdt_addr(wdt, WDT_RST));

	return 0;

}
@@ -83,10 +106,10 @@ static int qcom_wdt_restart(struct watchdog_device *wdd, unsigned long action, 
	 */

	timeout = 128 * wdt->rate / 1000;



	writel(0, wdt->base + WDT_EN);

	writel(1, wdt->base + WDT_RST);

	writel(timeout, wdt->base + WDT_BITE_TIME);

	writel(1, wdt->base + WDT_EN);

	writel(0, wdt_addr(wdt, WDT_EN));

	writel(1, wdt_addr(wdt, WDT_RST));

	writel(timeout, wdt_addr(wdt, WDT_BITE_TIME));

	writel(1, wdt_addr(wdt, WDT_EN));



	/*

	 * Actually make sure the above sequence hits hardware before sleeping.
@@ -119,9 +142,16 @@ static int qcom_wdt_probe(struct platform_device *pdev) 
	struct qcom_wdt *wdt;

	struct resource *res;

	struct device_node *np = pdev->dev.of_node;

	const u32 *regs;

	u32 percpu_offset;

	int ret;



	regs = of_device_get_match_data(&pdev->dev);

	if (!regs) {

		dev_err(&pdev->dev, "Unsupported QCOM WDT module\n");

		return -ENODEV;

	}



	wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);

	if (!wdt)

		return -ENOMEM;
@@ -172,6 +202,7 @@ static int qcom_wdt_probe(struct platform_device *pdev) 
	wdt->wdd.min_timeout = 1;

	wdt->wdd.max_timeout = 0x10000000U / wdt->rate;

	wdt->wdd.parent = &pdev->dev;

	wdt->layout = regs;



	if (readl(wdt->base + WDT_STS) & 1)

		wdt->wdd.bootstatus = WDIOF_CARDRESET;
@@ -208,8 +239,9 @@ static int qcom_wdt_remove(struct platform_device *pdev) 
}



static const struct of_device_id qcom_wdt_of_table[] = {

	{ .compatible = "qcom,kpss-timer" },

	{ .compatible = "qcom,scss-timer" },

	{ .compatible = "qcom,kpss-timer", .data = reg_offset_data_apcs_tmr },

	{ .compatible = "qcom,scss-timer", .data = reg_offset_data_apcs_tmr },

	{ .compatible = "qcom,kpss-wdt", .data = reg_offset_data_kpss },

	{ },

};

MODULE_DEVICE_TABLE(of, qcom_wdt_of_table);

CRA Git | Maintained and supported by SUSTech CRA and CCSE