upgrade_app
is the built-in upgrade flasher on the PlayStation Classic. It
reads an upgrade file from USB, verifies it, and flashes it. In normal boot,
it needs to be called to start the upgrade process. In recovery boot, it is
automatically started and polls for files on an attached USB drive to flash
the normal system. The program takes a single argument as a command. They are:
normal
: Reboots the system to recovery and waits to flash a normal system. It will refuse to boot into recovery if it detects recovery is not successfully