HDMI Output Lost

Robotics & Edge Computing Jetson Systems Jetson AGX Orin
1

Hi there. I am busy configuring my UART (as part of another ongoing forum) and have suddenly lost HDMI output after reflashing. I typically plug the hdmi in as soon as its finished flashing, so perhaps something went wrong when i plugged it in. Below is the boot logs, and dmesg. Please advise if there are any obvious things that could cause this problem.

dmesg.txt (38.0 KB)

output.zip (38.7 KB)

I have a fear that the display hardware inside the jetson is damaged as i also had the monitors hdmi get damaged at the same time. Please advise how I can check for any damage.

2

Ive got HDMI connected to DP2. I configured it and it worked in a previous forum. See attached, ive replicated it again from scratch to see what went wrong, but still having the same issues. See that forum here:

Im just going to post the troubvleshooting that im doing here incase it helps solve the issue

3

With the HDMI plugged in from boot, i cant access the debug uart to troubleshoot - so clearly something to do with the HPD is working. When i boot without HDMI connected and then plug it in after ive got access to uart, the card1-HDMI is disabled and disconnected.

4

please help share your xorg log after you hotplug the monitor.

5

Xorg.txt (15.8 KB)

6

I saw xorg shows the monitor is connected. What is the result of your xrandr ?

7

Is this the correct command:
root@ubuntudev:/home/devdev# xrandr
Can’t open display

cant recall what it should be

9

run xrandr without sudo .

do it like this.

export DISPLAY=:0
xrandr

10

Thanks for the guidance,

devdev@ubuntudev:~$ export DISPLAY=:0
devdev@ubuntudev:~$ xrandr
Authorization required, but no authorization protocol specified
Can’t open display :0

11

what is the result of this command?

ls -l ~/.Xauthority

12

Cant find the file/directory

I saw a previous forum had issues with the HPD, a file was overwriting the HPD to be active low. I’m not sure what the GPIO_ACTIVE_HIGH is in hex so cant check the dts file i attached above

comparing with other gpio_active_high values in hex, it seems as though the current dtc is 0x01, while active high seems to be 0x04

13

If xorg log could correctly tell you the connected/disconnected situation, then you don’t need to care about hpd gpio read result.

14

Understood, do you have any idea why the command “ls -l ~/.Xauthority” wont run?

15

Ignore that first. Please check if your xorg log really could detect your unplug and plug correctly.

16

Wasnt able to detect any change to HPD when i unplug and replug in display. I’ll reflash after some changes and let you know.

17

Wait. Let me check one thing first.

Is your xorg log content really got updated in each reboot?

I mean maybe you are checking a file that is totally not updated.

18

I may be making that mistake. I’m honestly not sure

19

I didn’t mean any special trick or anything that needs technical knowlege.

Just check the timestamp of your /var/log/xorg.0.log… is that a timestamp that happened right after you do a hotplug? or it is a date that is totally not today.

20

Oh, i understand. No, it seemed like the timestamp wasnt recent at all. Here is what I observed:

  • unplugged the HDMI

  • ran v# cat /var/log/Xorg.0.log

  • note this as the final line:
    [ 154.097] (II) Module libinput: vendor=“X.Org Foundation”
    [ 154.097] compiled for 1.20.14, module version = 1.2.1
    [ 154.097] Module class: X.Org XInput Driver
    [ 154.097] ABI class: X.Org XInput driver, version 24.1
    [ 154.097] (II) Using input driver ‘libinput’ for ‘gpio-keys’
    [ 154.099] (II) systemd-logind: got fd for /dev/input/event0 13:64 fd 39 paused 0
    [ 154.099] () gpio-keys: always reports core events
    [ 154.099] (    ) Option “Device” “/dev/input/event0”
    [ 154.103] (II) event0 - gpio-keys: is tagged by udev as: Keyboard
    [ 154.103] (II) event0 - gpio-keys: device is a keyboard
    [ 154.103] (II) event0 - gpio-keys: device removed
    [ 154.103] () Option “config_info” “udev:/sys/devices/platform/gpio-keys/input/input0/event0”
    [ 154.104] (II) XINPUT: Adding extended input device “gpio-keys” (type: KEYBOARD, id 6)
    [ 154.104] (    ) Option “xkb_model” “pc105”
    [ 154.104] (**) Option “xkb_layout” “us”
    [ 154.105] (II) event0 - gpio-keys: is tagged by udev as: Keyboard
    [ 154.105] (II) event0 - gpio-keys: device is a keyboard
    [ 154.872] (–) NVIDIA(GPU-0): DFP-0: disconnected
    [ 154.872] (–) NVIDIA(GPU-0): DFP-0: Internal TMDS
    [ 154.872] (–) NVIDIA(GPU-0): DFP-0: 165.0 MHz maximum pixel clock
    [ 154.872] (–) NVIDIA(GPU-0):

  • plugged the hdmi back in

  • issues the the same command cat /var/log/Xorg.0.log, and saw no new logs

i do notice 2 drm cards, HDMI is on card1. Is there the xorg generic to all displays?

21

so basically this file is some old file that is in use for a while ago?