Commit bc34b5f2 authored by Maxime Ripard's avatar Maxime Ripard
Browse files

ARM: sunxi: Rework the restart code 



The Allwinner sun6i (A31) has a slightly different watchdog, that
doesn't allow to use the already existing restart code.

Rework a bit the restart code to allow to plug in more easily different
restart handlers depending on the device tree.

In the past, we were also meaning sunxi as a generic name covering all
Allwinner SoCs. This won't be true anymore with the A31 (sun6i) that
differs pretty much from sun4i and sun5i, and we will end up having
sunxi, for sun4i and sun5i, and sun6i, which is neither consistent nor
convenient. So, while we're at it, also change sunxi to sun4i.

Signed-off-by: default avatarMaxime Ripard <maxime.ripard@free-electrons.com>
parent d7fbc6ca

Documentation/devicetree/bindings/watchdog/sunxi-wdt.txt→Documentation/devicetree/bindings/watchdog/sun4i-wdt.txt

+3 −3
Original line number Diff line number Diff line 
Allwinner sunXi Watchdog timer

Allwinner sun4i Watchdog timer



Required properties:



- compatible : should be "allwinner,sunxi-wdt"

- compatible : should be "allwinner,sun4i-wdt"

- reg : Specifies base physical address and size of the registers.



Example:



wdt: watchdog@01c20c90 {

	compatible = "allwinner,sunxi-wdt";

	compatible = "allwinner,sun4i-wdt";

	reg = <0x01c20c90 0x10>;

};

arch/arm/mach-sunxi/sunxi.c

+35 −23
Original line number Diff line number Diff line
@@ -24,50 +24,63 @@ 


#include <asm/mach/arch.h>

#include <asm/mach/map.h>

#include <asm/system_misc.h>



#include "sunxi.h"



#define WATCHDOG_CTRL_REG	0x00

#define WATCHDOG_CTRL_RESTART		(1 << 0)

#define WATCHDOG_MODE_REG	0x04

#define WATCHDOG_MODE_ENABLE		(1 << 0)

#define WATCHDOG_MODE_RESET_ENABLE	(1 << 1)

#define SUN4I_WATCHDOG_CTRL_REG		0x00

#define SUN4I_WATCHDOG_CTRL_RESTART		(1 << 0)

#define SUN4I_WATCHDOG_MODE_REG		0x04

#define SUN4I_WATCHDOG_MODE_ENABLE		(1 << 0)

#define SUN4I_WATCHDOG_MODE_RESET_ENABLE	(1 << 1)



static void __iomem *wdt_base;



static void sunxi_setup_restart(void)

{

	struct device_node *np = of_find_compatible_node(NULL, NULL,

						"allwinner,sunxi-wdt");

	if (WARN(!np, "unable to setup watchdog restart"))

		return;



	wdt_base = of_iomap(np, 0);

	WARN(!wdt_base, "failed to map watchdog base address");

}



static void sunxi_restart(char mode, const char *cmd)

static void sun4i_restart(char mode, const char *cmd)

{

	if (!wdt_base)

		return;



	/* Enable timer and set reset bit in the watchdog */

	writel(WATCHDOG_MODE_ENABLE | WATCHDOG_MODE_RESET_ENABLE,

		wdt_base + WATCHDOG_MODE_REG);

	writel(SUN4I_WATCHDOG_MODE_ENABLE | SUN4I_WATCHDOG_MODE_RESET_ENABLE,

	       wdt_base + SUN4I_WATCHDOG_MODE_REG);



	/*

	 * Restart the watchdog. The default (and lowest) interval

	 * value for the watchdog is 0.5s.

	 */

	writel(WATCHDOG_CTRL_RESTART, wdt_base + WATCHDOG_CTRL_REG);

	writel(SUN4I_WATCHDOG_CTRL_RESTART, wdt_base + SUN4I_WATCHDOG_CTRL_REG);



	while (1) {

		mdelay(5);

		writel(WATCHDOG_MODE_ENABLE | WATCHDOG_MODE_RESET_ENABLE,

			wdt_base + WATCHDOG_MODE_REG);

		writel(SUN4I_WATCHDOG_MODE_ENABLE | SUN4I_WATCHDOG_MODE_RESET_ENABLE,

		       wdt_base + SUN4I_WATCHDOG_MODE_REG);

	}

}



static struct of_device_id sunxi_restart_ids[] = {

	{ .compatible = "allwinner,sun4i-wdt", .data = sun4i_restart },

	{ /*sentinel*/ }

};



static void sunxi_setup_restart(void)

{

	const struct of_device_id *of_id;

	struct device_node *np;



	np = of_find_matching_node(NULL, sunxi_restart_ids);

	if (WARN(!np, "unable to setup watchdog restart"))

		return;



	wdt_base = of_iomap(np, 0);

	WARN(!wdt_base, "failed to map watchdog base address");



	of_id = of_match_node(sunxi_restart_ids, np);

	WARN(!of_id, "restart function not available");



	arm_pm_restart = of_id->data;

}



static struct map_desc sunxi_io_desc[] __initdata = {

	{

		.virtual	= (unsigned long) SUNXI_REGS_VIRT_BASE,
@@ -105,7 +118,6 @@ DT_MACHINE_START(SUNXI_DT, "Allwinner A1X (Device Tree)") 
	.init_machine	= sunxi_dt_init,

	.map_io		= sunxi_map_io,

	.init_irq	= irqchip_init,

	.restart	= sunxi_restart,

	.init_time	= sunxi_timer_init,

	.dt_compat	= sunxi_board_dt_compat,

MACHINE_END

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