From: Michael Walle <michael@xxxxxxxx>
commit ea104a9e4d3e9ebc26fb78dac35585b142ee288b upstream.
The restart handler is missing two things, first, the registers
has to be unlocked and second there is no synchronization for the
write_relaxed() calls.
This was tested on a custom board with the NXP LS1028A SoC.
Fixes: 6c5c0d48b686c ("watchdog: sp805: add restart handler")
Signed-off-by: Michael Walle <michael@xxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20200327162450.28506-1-michael@xxxxxxxx
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Wim Van Sebroeck <wim@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/watchdog/sp805_wdt.c | 4 ++++
1 file changed, 4 insertions(+)
--- a/drivers/watchdog/sp805_wdt.c
+++ b/drivers/watchdog/sp805_wdt.c
@@ -137,10 +137,14 @@ wdt_restart(struct watchdog_device *wdd,
{
struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
+ writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
writel_relaxed(0, wdt->base + WDTCONTROL);
writel_relaxed(0, wdt->base + WDTLOAD);
writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base + WDTCONTROL);
+ /* Flush posted writes. */
+ readl_relaxed(wdt->base + WDTLOCK);
+
return 0;
}
