Disable Boot Messages on Jetson-TX1 (R28.1 (JetPack 3.1))

Hi all,

How can i disable all booting messages appears on HDMI screen when using JetPack 3.1?
I have earlier followed this (for JetPack 3.0):
https://devtalk.nvidia.com/default/topic/931661/disable-boot-messages-on-jetson-tx1/

But now that line that I normally edited has changed to:

APPEND ${cbootargs} root=/dev/mmcblk0p1 rw rootwait

How can I get the value of ${cbootargs} and remove the fbcon=map:0 console=tty1 that I normally do?

Is the only way to start over with a new image and change it when creating it from scratch? (I hope not)

I guess if someone can tell me the values that cbootargs hold then I can just change them? (type them instead of the variable).

/Kasper

Ok, I have done the following and it seems to work:

edit extlinux.conf
change:

APPEND ${cbootargs} root=/dev/mmcblk0p1 rw rootwait

to:

APPEND console=ttyS0,115200n8 OS=l4t net.ifnames=0 root=/dev/mmcblk0p1 rw rootwait quiet

I found the $cbootargs in the p2371-2180.conf file that is used when you create a new image. I hope this is the right approach?

Double post.

“cbootargs” is just an environment variable in U-Boot…put in place by that device tree…and when Linux boots, extlinux.conf appends to that. I guess the trick with having part of this in U-Boot is that it is more difficult to “unappend” what has been appended. Some variables simply use the last value seen, others may behave oddly if a variable is shown twice (or at least unpredictably). Basically if you edit the device tree in the right place and flash it to the partition (for R28.1…earlier releases don’t do this), then cbootargs will be updated in U-Boot.

If you have a serial console you can interrupt boot and see what U-Boot environment variables are with “printenv”. There are also commands to change this…and if you boot without saving, then this applies to one boot. If you saveenv, then this is persistent…but I don’t know if at the next boot the device tree will overwrite your changes or not. Having the device tree changed and written to the right partition will work.

Slightly different naming exists between a TX1 partition name versus a TX2 partition name, but mostly the R28.1 dtb update is the same. See:
https://elinux.org/Jetson/TX2_DTB

Thanks for the fast reply, linuxdev.