ARM: SAMSUNG: Add watchdog reset driver (a4658e57) · Commits · 戴 / test

arch/arm/plat-samsung/Kconfig

+6 −0

Original line number	Diff line number	Diff line
		@@ -475,6 +475,12 @@ config SAMSUNG_WAKEMASK
		and above. This code allows a set of interrupt to wakeup-mask
		mappings. See <plat/wakeup-mask.h>

		config SAMSUNG_WDT_RESET
		bool
		help
		Compile support for system restart by triggering watchdog reset.
		Used on SoCs that do not provide dedicated reset control.

		config S5P_PM
		bool
		help

arch/arm/plat-samsung/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -56,6 +56,7 @@ obj-$(CONFIG_PM) += pm-gpio.o
		obj-$(CONFIG_SAMSUNG_PM_CHECK) += pm-check.o

		obj-$(CONFIG_SAMSUNG_WAKEMASK) += wakeup-mask.o
		obj-$(CONFIG_SAMSUNG_WDT_RESET) += watchdog-reset.o

		obj-$(CONFIG_S5P_PM) += s5p-pm.o s5p-irq-pm.o
		obj-$(CONFIG_S5P_SLEEP) += s5p-sleep.o

arch/arm/plat-samsung/include/plat/watchdog-reset.h

+9 −0

Original line number	Diff line number	Diff line
		@@ -10,6 +10,9 @@
		* published by the Free Software Foundation.
		*/

		#ifndef __PLAT_SAMSUNG_WATCHDOG_RESET_H
		#define __PLAT_SAMSUNG_WATCHDOG_RESET_H

		#include <plat/clock.h>
		#include <plat/regs-watchdog.h>
		#include <mach/map.h>
		@@ -44,3 +47,9 @@ static inline void arch_wdt_reset(void)
		/* delay to allow the serial port to show the message */
		mdelay(50);
		}

		extern void samsung_wdt_reset(void);
		extern void samsung_wdt_reset_of_init(void);
		extern void samsung_wdt_reset_init(void __iomem *base);

		#endif /* __PLAT_SAMSUNG_WATCHDOG_RESET_H */

arch/arm/plat-samsung/watchdog-reset.c

0 → 100644

+97 −0

Original line number	Diff line number	Diff line
		/* arch/arm/plat-samsung/watchdog-reset.c
		*
		* Copyright (c) 2008 Simtec Electronics
		* Ben Dooks <ben@simtec.co.uk>
		*
		* Coyright (c) 2013 Tomasz Figa <tomasz.figa@gmail.com>
		*
		* Watchdog reset support for Samsung SoCs.
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License version 2 as
		* published by the Free Software Foundation.
		*/

		#include <linux/clk.h>
		#include <linux/err.h>
		#include <linux/io.h>
		#include <linux/delay.h>
		#include <linux/of.h>
		#include <linux/of_address.h>

		#define S3C2410_WTCON 0x00
		#define S3C2410_WTDAT 0x04
		#define S3C2410_WTCNT 0x08

		#define S3C2410_WTCON_ENABLE (1 << 5)
		#define S3C2410_WTCON_DIV16 (0 << 3)
		#define S3C2410_WTCON_RSTEN (1 << 0)
		#define S3C2410_WTCON_PRESCALE(x) ((x) << 8)

		static void __iomem *wdt_base;
		static struct clk *wdt_clock;

		void samsung_wdt_reset(void)
		{
		if (!wdt_base) {
		pr_err("%s: wdt reset not initialized\n", __func__);
		/* delay to allow the serial port to show the message */
		mdelay(50);
		return;
		}

		if (!IS_ERR(wdt_clock))
		clk_prepare_enable(wdt_clock);

		/* disable watchdog, to be safe */
		__raw_writel(0, wdt_base + S3C2410_WTCON);

		/* put initial values into count and data */
		__raw_writel(0x80, wdt_base + S3C2410_WTCNT);
		__raw_writel(0x80, wdt_base + S3C2410_WTDAT);

		/* set the watchdog to go and reset... */
		__raw_writel(S3C2410_WTCON_ENABLE \| S3C2410_WTCON_DIV16 \|
		S3C2410_WTCON_RSTEN \| S3C2410_WTCON_PRESCALE(0x20),
		wdt_base + S3C2410_WTCON);

		/* wait for reset to assert... */
		mdelay(500);

		pr_err("Watchdog reset failed to assert reset\n");

		/* delay to allow the serial port to show the message */
		mdelay(50);
		}

		#ifdef CONFIG_OF
		static const struct of_device_id s3c2410_wdt_match[] = {
		{ .compatible = "samsung,s3c2410-wdt" },
		{},
		};

		void __init samsung_wdt_reset_of_init(void)
		{
		struct device_node *np;

		np = of_find_matching_node(NULL, s3c2410_wdt_match);
		if (!np) {
		pr_err("%s: failed to find watchdog node\n", __func__);
		return;
		}

		wdt_base = of_iomap(np, 0);
		if (!wdt_base) {
		pr_err("%s: failed to map watchdog registers\n", __func__);
		return;
		}

		wdt_clock = of_clk_get(np, 0);
		}
		#endif

		void __init samsung_wdt_reset_init(void __iomem *base)
		{
		wdt_base = base;
		wdt_clock = clk_get(NULL, "watchdog");
		}

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