How to enable watchdog in xavier NX

Hi guys,
I’d like to use watchdog timer , but i cannot find any watchdog dev in my device.
there is nothing to run <ls /dev/w*> in the terminal.
how should I do?

The default r32.4 should enable the watchdog.
Could you check the kernel message?

[    0.708497] hw-breakpoint: found 6 breakpoint and 4 watchpoint registers.
[    0.947480] tegra_wdt_t18x 30c0000.watchdog: Expiry count is deprecated
[    0.947746] tegra_wdt_t18x 30c0000.watchdog: Tegra WDT init timeout = 120 sec
[    0.947780] tegra_wdt_t18x 30c0000.watchdog: Registered successfully
[    4.658489] systemd[1]: Started Forward Password Requests to Wall Directory Watch.