watchdog: rti: support SPL (or re-start)
If the RTI watchdog has been enabled in SPL, enabling it in U-Boot proper
fails because it can only be enabled once in HW and never stopped. This
however leads to a situation that wdt_cyclic() watchdog trigger is not
being started any longer and the WDT fires at some point.
Allow for WDT re-start by not bailing out if the [previously] configured
period matches the one to be configured.
Enabling in [A53] SPL has been tested on AM62x-based HW (where [A53] SPL is
responsible for loading R5 DM firmware and not this driver).
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
index 99168d0..320c5ca 100644
--- a/drivers/watchdog/rti_wdt.c
+++ b/drivers/watchdog/rti_wdt.c
@@ -131,18 +131,19 @@
u32 timer_margin;
int ret;
- if (readl(priv->regs + RTIDWDCTRL) == WDENABLE_KEY)
+ timer_margin = timeout_ms * priv->clk_hz / 1000;
+ timer_margin >>= WDT_PRELOAD_SHIFT;
+ if (timer_margin > WDT_PRELOAD_MAX)
+ timer_margin = WDT_PRELOAD_MAX;
+
+ if (readl(priv->regs + RTIDWDCTRL) == WDENABLE_KEY &&
+ readl(priv->regs + RTIDWDPRLD) != timer_margin)
return -EBUSY;
ret = rti_wdt_load_fw(dev);
if (ret < 0)
return ret;
- timer_margin = timeout_ms * priv->clk_hz / 1000;
- timer_margin >>= WDT_PRELOAD_SHIFT;
- if (timer_margin > WDT_PRELOAD_MAX)
- timer_margin = WDT_PRELOAD_MAX;
-
writel(timer_margin, priv->regs + RTIDWDPRLD);
writel(RTIWWDRX_NMI, priv->regs + RTIWWDRXCTRL);
writel(RTIWWDSIZE_50P, priv->regs + RTIWWDSIZECTRL);