Remote reboot into recovery mode?

Robotics & Edge Computing Jetson & Embedded Systems Jetson TK1
1

whether it is possible to remote reboot into recovery mode from running os?

edit:

i found way by serial console

Tegra124 (Jetson TK1)
enterrcm

Entering RCM...

But is any way add this to u-boot menu?

2

I doubt this could be done (though it might). Prior to a boot loader menu it has to set up registers at a very low level, including things like clock timings, tri-state logic, voltage-sensitive board settings, etc. Though I could be wrong I believe the recovery mode button changes registers before the boot loader even begins and the register states may not be compatible. As for security, be glad it doesn’t do this :P

On the other hand, you might find someone from nVidia that can answer this without doubt.

3

http://http.download.nvidia.com/tegra-public-appnotes/tegra-boot-flow.html

“If Tegra PMC register scratch0 bit 2 is set at power-up, recovery mode will be entered. This register bit is not cleared when Tegra resets, so any software may set this bit, then reboot, to request recovery mode.”

That one doesn’t list T124 though.

4

To answer Santyago’s initial question, the L4T kernel accepts “forced-recovery” as a command to the reboot syscall, e.g.:

syscall(SYS_reboot, 
            LINUX_REBOOT_MAGIC1, 
        LINUX_REBOOT_MAGIC2, 
        LINUX_REBOOT_CMD_RESTART2, "forced-recovery");