On 09/19/2014 08:07 PM, Guenter Roeck wrote:
On 09/18/2014 11:29 PM, Jisheng Zhang wrote:
The kernel core now provides an API to trigger a system restart.
Register with it to support restarting the system via. watchdog.
Signed-off-by: Jisheng Zhang <jszh...@marvell.com>
---
drivers/watchdog/dw_wdt.c | 27 +++++++++++++++++++++++++++
1 file changed, 27 insertions(+)
diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c
index ad0619d..4ca41e9 100644
--- a/drivers/watchdog/dw_wdt.c
+++ b/drivers/watchdog/dw_wdt.c
@@ -29,9 +29,11 @@
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
+#include <linux/notifier.h>
#include <linux/of.h>
#include <linux/pm.h>
#include <linux/platform_device.h>
+#include <linux/reboot.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <linux/uaccess.h>
@@ -62,6 +64,7 @@ static struct {
unsigned long next_heartbeat;
struct timer_list timer;
int expect_close;
+ struct notifier_block restart_handler;
} dw_wdt;
static inline int dw_wdt_is_enabled(void)
@@ -119,6 +122,22 @@ static void dw_wdt_keepalive(void)
WDOG_COUNTER_RESTART_REG_OFFSET);
}
+static int dw_wdt_restart_handle(struct notifier_block *this,
+ unsigned long mode, void *cmd)
+{
+ u32 val;
+
+ writel(0, dw_wdt.regs + WDOG_TIMEOUT_RANGE_REG_OFFSET);
+ val = readl(dw_wdt.regs + WDOG_CONTROL_REG_OFFSET);
+ if (val & WDOG_CONTROL_REG_WDT_EN_MASK)
+ writel(WDOG_COUNTER_RESTART_KICK_VALUE, dw_wdt.regs +
+ WDOG_COUNTER_RESTART_REG_OFFSET);
+ else
+ writel(WDOG_CONTROL_REG_WDT_EN_MASK,
+ dw_wdt.regs + WDOG_CONTROL_REG_OFFSET);
Don't you have to write WDOG_COUNTER_RESTART_KICK_VALUE into
WDOG_COUNTER_RESTART_REG_OFFSET in the else case as well ?
According to the datasheet, it should be sufficient to
- Write 0 into WDOG_TIMEOUT_RANGE_REG_OFFSET to select the minimum timeout
period
- Write 0x1 into WDOG_CONTROL_REG_OFFSET to enable the watchdog and select reset
as desired action. This can be unconditional.
Writing into the restart register should not be necessary.
Thanks,
Guenter
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
