XO-1.75/Kernel/FIQ

Change /etc/init/ttySx.conf

Change /dev/ttyS2 to /dev/ttyFIQ0 two times in this file.

sed --in-place 's/ttyS2/ttyFIQ0/g' /etc/init/ttySx.conf

Corrects missing serial console shell.

Disable watchdog

The watchdog is normally not enabled. If it is, and a hang occurs, and the FIQ debugger is entered, only a short time is available for interaction before the watchdog restarts the CPU. If you have enabled the watchdog, disabling by removing the empty marker file:

rm /runin/watchdog