During the BOOT image creation, config_lpd_wdt.cdo added in boot.bif will configure the expiry action of the LPD WDT to Subsystem Restart. PLM configures this action in the error management module. Whenever LPD WDT expires, the PLM gets the notification to perform the configured action.
RPU application of the TRD waits for the command from APU over libmetal. When it receives ‘Kill Watchdog’ request it will set a flag to stop the watchdog kicks. This will result in the watchdog expiry after the configured time. And hence PLM will perform Subsystem Restart.