Hi As there is none u-boot mailing list anymore I will ask question here. Maybe someone will know answer. I have two watchdogs in hardware. One is synopsys designware one (so standard u-boot global functions hw_watchdog_init and hw_watchdog_reset are implemented by open source synopsys designware driver. And I have second watchdog for which I implement my own driver and it bases on device tree model. Let's see at below code: include/watchdog.h (I added second config and modify macro WATCHDOG_RESET) [code] extern void hw_watchdog_reset(void); #if defined(CONFIG_DM_HW_WATCHDOG) extern void dm_hw_watchdog_reset(void); #define WATCHDOG_RESET() {hw_watchdog_reset(); dm_hw_watchdog_reset();} #else #define WATCHDOG_RESET hw_watchdog_reset #endif [/code] implementation of dm_hw_watchdog_reset function: [code] #ifndef CONFIG_SPL_BUILD struct udevice* wdt = NULL; void dm_hw_watchdog_reset(void) { int ret; if (wdt) { printf("dm_hw_watchdog_reset\n"); wdt_reset(wdt); } else { ret = 2+8; /*ret = uclass_get_device_by_driver(UCLASS_WDT, DM_GET_DRIVER(wdt_bmu), &wdt); if (ret) printf("Lack of watchdog device\n"); else wdt_start(wdt, 60000, 0);*/ } } #else void dm_hw_watchdog_reset(void) { } #endif [/code] What is weird when Uboot is started it prints tens of times: " dm_hw_watchdog_reset" and then hangs on. I have to power on/off the board and recovery it with the aid of jtag. I don't understand why 'wdt' variable isn't NULL and code under if (wdt) is executed. Seems like something uboot specific.