If the watchdog hardware is already enabled during the boot process, when the Linux watchdog driver loads, it should reset the watchdog and tell the watchdog framework. As a result, ping can be generated from the watchdog framework (if CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED is set), until the userspace watchdog daemon takes over control Verified : Watchdog enable in Uboot + HANDLE_BOOT_ENABLE is not set + daemon watchdog in userland ON ==> No reset IWDG2 Watchdog enable in Uboot + HANDLE_BOOT_ENABLE is not set ==> Reset IWDG2 Watchdog enable in Uboot + HANDLE_BOOT_ENABLE=y ==> No reset IWDG2 Watchdog enable in Uboot + HANDLE_BOOT_ENABLE=y + daemon watchdog in userland ON puis OFF ==> Reset IWDG2 Watchdog disable in Uboot + HANDLE_BOOT_ENABLE is not set ==> No reset IWDG2 Watchdog disable in Uboot + HANDLE_BOOT_ENABLE=y ==> No reset IWDG2 Watchdog disable in Uboot + HANDLE_BOOT_ENABLE=y + daemon watchdog in userland ON ==> No reset IWDG2 Watchdog disable in Uboot + HANDLE_BOOT_ENABLE=y + daemon watchdog in userland ON puis OFF ==> Reset IWDG2 Christophe Roullier (1): drivers: watchdog: stm32_iwdg: set WDOG_HW_RUNNING at probe drivers/watchdog/stm32_iwdg.c | 57 ++++++++++++++++++++++++----------- 1 file changed, 40 insertions(+), 17 deletions(-) -- 2.17.1