From: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxxxx>
Firmware (SC) WDT can be already enabled in U-Boot. Detect this case and
make CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED functional by setting
WDOG_HW_RUNNING.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxxxx>
---
drivers/watchdog/imx_sc_wdt.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
diff --git a/drivers/watchdog/imx_sc_wdt.c b/drivers/watchdog/imx_sc_wdt.c
index e51fe1b78518..e6d567b11795 100644
--- a/drivers/watchdog/imx_sc_wdt.c
+++ b/drivers/watchdog/imx_sc_wdt.c
@@ -56,6 +56,25 @@ static int imx_sc_wdt_ping(struct watchdog_device *wdog)
return 0;
}
+static bool imx_sc_wdt_is_running(void)
+{
+ struct arm_smccc_res res;
+
+ arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_START_WDOG,
+ 0, 0, 0, 0, 0, 0, &res);
+
+ /* Already enabled (SC_TIMER_ERR_BUSY)? */
+ if (res.a0 == SC_TIMER_ERR_BUSY)
+ return true;
+
+ /* Undo only if that was us who has (successfully) enabled the WDT */
+ if (!res.a0)
+ arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_STOP_WDOG,
+ 0, 0, 0, 0, 0, 0, &res);
+
+ return false;
+}
+
static int imx_sc_wdt_start(struct watchdog_device *wdog)
{
struct arm_smccc_res res;
@@ -183,6 +202,9 @@ static int imx_sc_wdt_probe(struct platform_device *pdev)
if (ret)
return ret;
+ if (imx_sc_wdt_is_running())
+ set_bit(WDOG_HW_RUNNING, &wdog->status);
+
watchdog_stop_on_reboot(wdog);
watchdog_stop_on_unregister(wdog);
--
2.46.0
