Commit db60d55e authored by Alexander Sverdlin's avatar Alexander Sverdlin Committed by Wim Van Sebroeck
Browse files

watchdog: imx_sc_wdt: detect if already running 



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: default avatarAlexander Sverdlin <alexander.sverdlin@siemens.com>
Reviewed-by: default avatarGuenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20240828060212.108608-1-alexander.sverdlin@siemens.com


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarWim Van Sebroeck <wim@linux-watchdog.org>
parent 6adb5591

drivers/watchdog/imx_sc_wdt.c

+22 −0
Original line number Diff line number Diff line
@@ -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);