wdt command


wdt list
wdt dev [<name>]
wdt start <timeout_ms> [flags]
wdt stop
wdt reset
wdt expirer [flags]


The wdt command is used to control watchdog timers.

The ‘wdt list’ command shows a list of all watchdog devices.

The ‘wdt dev’ command called without argument shows the current watchdog device. The current device is set when passing the name of the device as argument.

The ‘wdt start’ command starts the current watchdog timer.

The ‘wdt stop’ command stops the current watchdog timer.

The ‘wdt reset’ command resets the current watchdog timer without stopping it.

The ‘wdt expire’ command let’s the current watchdog timer expire immediately. This will lead to a reset.


name of the watchdog device


timeout interval in milliseconds


unsigned long value passed to the driver. The usage is driver specific. The value is ignored by most drivers.


   => wdt dev
   No watchdog timer device set!
   => wdt list
   watchdog@1c20ca0 (sunxi_wdt)
   => wdt dev watchdog@1c20ca0
   => wdt dev
   dev: watchdog@1c20ca0
   => wdt start 3000
   => wdt reset
   => wdt stop
   => wdt expire

   U-Boot SPL 2022.04-rc3 (Mar 25 2022 - 13:48:33 +0000)

In the example above '(sunxi_wdt)' refers to the driver for the watchdog


The command is only available if CONFIG_CMD_WDT=y.

Return value

The return value $? is 0 if the command succeeds, 1 upon failure.