ARM: sunxi: Add sunxi restart function via onchip watchdog
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
diff --git a/arch/arm/mach-sunxi/sunxi.c b/arch/arm/mach-sunxi/sunxi.c
index 13d4d96..dc634ae 100644
--- a/arch/arm/mach-sunxi/sunxi.c
+++ b/arch/arm/mach-sunxi/sunxi.c
@@ -12,6 +12,7 @@
#include <linux/kernel.h>
#include <linux/init.h>
+#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/io.h>
@@ -26,6 +27,36 @@
#include "sunxi.h"
+#define WATCHDOG_CTRL_REG 0x00
+#define WATCHDOG_MODE_REG 0x04
+
+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)
+{
+ if (!wdt_base)
+ return;
+
+ /* Enable timer and set reset bit in the watchdog */
+ writel(3, wdt_base + WATCHDOG_MODE_REG);
+ writel(0xa57 << 1 | 1, wdt_base + WATCHDOG_CTRL_REG);
+ while(1) {
+ mdelay(5);
+ writel(3, wdt_base + WATCHDOG_MODE_REG);
+ }
+}
+
static struct map_desc sunxi_io_desc[] __initdata = {
{
.virtual = (unsigned long) SUNXI_REGS_VIRT_BASE,
@@ -42,6 +73,8 @@
static void __init sunxi_dt_init(void)
{
+ sunxi_setup_restart();
+
of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
}
@@ -56,6 +89,7 @@
.map_io = sunxi_map_io,
.init_irq = sunxi_init_irq,
.handle_irq = sunxi_handle_irq,
+ .restart = sunxi_restart,
.timer = &sunxi_timer,
.dt_compat = sunxi_board_dt_compat,
MACHINE_END