I am trying to get the KGDB going for AGX Xavier. Currently, my serial connection(minicom) to the Xavier box is through the micro-USB FTDI serial device (/dev/ttyTCU0).
root@magneto:~# cat /proc/cmdline root=/dev/mmcblk0p1 rw rootwait console=ttyTCU0,115200n8 console=tty0 fbcon=map:0 net.ifnames=0 rootfstype=ext4 OS=l4t memtype=0 video=tegrafb no_console_suspend=1 earlycon=tegra_comb_uart,mmio32,0x0c168000 gpt tegra_fbmem=0x140000@0x96183000 lut_mem=0x2008@0x9607e000 usbcore.old_scheme_first=1 tegraid=126.96.36.199.0 tegra_keep_boot_clocks maxcpus=8 boot.slot_suffix= boot.ratchetvalues=0.2.2 sdhci_tegra.en_boot_part_access=1 root@magneto:~#
But when I get to the KDB prompt by following below steps:
echo ttyTCU0 > /sys/module/kgdboc/parameters/kgdboc echo g > /proc/sysrq-trigger
the system doesn’t accept any input from the keyboard. So, I have to hard reset the system. I think that the driver for ttyTCU0 needs similar hooks as ttyS0 has. Can you please guide me in fixing this?
Also, I tried connecting the Adafruit USB to TTL Serial Cable – Debug / Console Cable for Raspberry Pi cable from a TX2 to the 40-pin expansion header. But I don’t see anything on the minicom opened for that /dev/ttyUSB* port. I have set console=ttyS0, 115200n8 in the kernel boot parameter through flash.sh script. Am I missing something here? I can provide photo of the connection I have made, but it is similar to that of TX2’s with Pin1 assumed to be the upper-right pin of the expansion header.
Please let me know if more information is required.