| Message ID | 20200327162450.28506-1-michael@walle.cc (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | watchdog: sp805: fix restart handler | expand |
On 3/27/20 9:24 AM, Michael Walle wrote: > 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@walle.cc> Reviewed-by: Guenter Roeck <linux@roeck-us.net> > --- > drivers/watchdog/sp805_wdt.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c > index 53e04926a7b2..190d26e2e75f 100644 > --- a/drivers/watchdog/sp805_wdt.c > +++ b/drivers/watchdog/sp805_wdt.c > @@ -137,10 +137,14 @@ wdt_restart(struct watchdog_device *wdd, unsigned long mode, void *cmd) > { > 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; > } > >
diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c index 53e04926a7b2..190d26e2e75f 100644 --- a/drivers/watchdog/sp805_wdt.c +++ b/drivers/watchdog/sp805_wdt.c @@ -137,10 +137,14 @@ wdt_restart(struct watchdog_device *wdd, unsigned long mode, void *cmd) { 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; }
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@walle.cc> --- drivers/watchdog/sp805_wdt.c | 4 ++++ 1 file changed, 4 insertions(+)