system could not boot up

Linux system folder “/lib” in Tegra A are deleted by mistake, which makes the system unable to boot up.
while system power on, bootloader fails to load Linux image, and then the bootloader repeatedly loads Linux image.
How to deal with this situation that can make the system restore? Thanks.

More info for debug:
Connect with the serial port When the system is powered on, and the output of the screen is :
booting and load Linux image fails,
system will reboot automatically…

and then repeatedly

Hi zhoujianwen,

Please follow the instruction in Linux Development Guide to flash your DRIVE PX2 device.