Hdmi doesn’t work for some monitors ,Discovering Again

504566020 · April 6, 2023, 2:41am

The same issue occurred when we conducted EMC testing and found several monitors that were unable to adapt.

with custom board ，jetpack 5.1 ，L4T 35.2.1
I found that hdmi adapts to specific monitors.

with DELL monitor model is P2319H is ok。
but with DELL monitor model is U2414Hb cannot display。

and this time，is with Lenovo monitor model is P27u-10 cannot display.

Last post
（https://forums.developer.nvidia.com/t/hdmi-doesnt-work-for-some-monitors/243444）

WayneWWW · April 6, 2023, 3:28am

Hi,

請問一下你們有orin nx + xavier nx devkit可以測試這台螢幕嗎?

Do you have Orin NX + Xavier NX devkit on there side to test this monitor?

504566020 · April 6, 2023, 3:34am

Hi，
我们有orin 的 devikit ，但是这个开发板，只有DP接口。没有hdmi接口。而我们自己做的板子，是hdmi接口。

WayneWWW · April 6, 2023, 3:40am

基本上希望你能弄到orin NX + xavier nx做devkit測試. 所有的問題能在公板上複製最好.
如果真的沒辦法的話麻煩先dump這個螢幕的 xrandr的資訊給我

Basically, we would hope you can get on Orin NX + Xavier NX devkit to test.
If you really cannot get one, please dump the xrandr info based on this monitor.

504566020 · April 6, 2023, 6:08am

我们有 xavier NX 核心板，然后在我们自己做的xarvier NX 的底板上，是没有这个问题的。

WayneWWW · April 6, 2023, 6:10am

Hi,

用xaiver nx module比較是沒有意義的. Orin的display架構跟以前完全不一樣.
所以我們只能請你們用orin nx + xavier nx devkit. Orin nx 跟Orin AGX的架構才是一樣的這樣比較才有用.

It does not help with xavier nx module. Orin display structure is totally different from previous SoC.

Thus, we can only ask you to try Orin NX + Xavier NX devkit. Orin NX is same display driver as Orin AGX. Only this check matters.

504566020 · April 6, 2023, 6:26am

好的，请问，如何操作，dump xrandr呢?

以下是使用DELL U2414Hb拿到的dmesg打印。
dmesg.all_20230406 (97.7 KB)

WayneWWW · April 6, 2023, 6:28am

請不要用root跑xrandr.
跑xrandr之前請先export DISPLAY=:0

你可以先用能正常運作的HDMI螢幕操作確認步驟能正確使用之後在移往有問題的那個螢幕

504566020 · April 6, 2023, 6:41am

现在使用的是DELL P2319H，显示正常。
dmesg_dell2319.txt (67.4 KB)

WayneWWW · April 6, 2023, 6:42am

也試試看 export DISPLAY=:1

如果xrandr還是無法給出結果. 麻煩把/var/log/Xorg.0.log 上傳

504566020 · April 6, 2023, 6:50am

现在使用的是DELL P2319H，显示正常。

Xorg.0.log (15.7 KB)
Xorg.0.log.old (28.4 KB)

504566020 · April 6, 2023, 6:56am

如果我从DELL P2319H 换为DELL U2414H，Xrog.0.log 增加的打印如下。显示器不正常

[ 21.804] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): connected
[ 21.804] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): Internal TMDS
[ 21.804] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): 165.0 MHz maximum pixel clock
[ 21.804] (–) NVIDIA(GPU-0):
[ 336.418] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): connected
[ 336.418] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): Internal TMDS
[ 336.418] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): 165.0 MHz maximum pixel clock
[ 336.418] (–) NVIDIA(GPU-0):
[ 336.566] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): connected
[ 336.567] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): Internal TMDS
[ 336.567] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): 165.0 MHz maximum pixel clock
[ 336.567] (–) NVIDIA(GPU-0):
[ 336.667] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): connected
[ 336.667] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): Internal TMDS
[ 336.667] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): 165.0 MHz maximum pixel clock
[ 336.667] (–) NVIDIA(GPU-0):
[ 336.765] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): connected
[ 336.765] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): Internal TMDS
[ 336.765] (–) NVIDIA(GPU-0): DELL P2319H (DFP-1): 165.0 MHz maximum pixel clock
[ 336.765] (–) NVIDIA(GPU-0):
[ 337.190] (–) NVIDIA(GPU-0): DFP-1: disconnected
[ 337.191] (–) NVIDIA(GPU-0): DFP-1: Internal TMDS
[ 337.191] (–) NVIDIA(GPU-0): DFP-1: 165.0 MHz maximum pixel clock
[ 337.191] (–) NVIDIA(GPU-0):
[ 337.217] (–) NVIDIA(GPU-0): DFP-1: disconnected
[ 337.217] (–) NVIDIA(GPU-0): DFP-1: Internal TMDS
[ 337.217] (–) NVIDIA(GPU-0): DFP-1: 165.0 MHz maximum pixel clock
[ 337.217] (–) NVIDIA(GPU-0):
[ 337.222] (–) NVIDIA(GPU-0): DFP-0: disconnected
[ 337.223] (–) NVIDIA(GPU-0): DFP-0: Internal DisplayPort
[ 337.223] (–) NVIDIA(GPU-0): DFP-0: 2380.0 MHz maximum pixel clock
[ 337.223] (–) NVIDIA(GPU-0):
[ 337.248] (–) NVIDIA(GPU-0): DFP-1: disconnected
[ 337.248] (–) NVIDIA(GPU-0): DFP-1: Internal TMDS
[ 337.248] (–) NVIDIA(GPU-0): DFP-1: 165.0 MHz maximum pixel clock
[ 337.248] (–) NVIDIA(GPU-0):
[ 337.348] (II) NVIDIA(0): Setting mode “NULL”
[ 337.406] (–) NVIDIA(GPU-0): DFP-0: disconnected
[ 337.406] (–) NVIDIA(GPU-0): DFP-0: Internal DisplayPort
[ 337.406] (–) NVIDIA(GPU-0): DFP-0: 2380.0 MHz maximum pixel clock
[ 337.406] (–) NVIDIA(GPU-0):
[ 337.432] (–) NVIDIA(GPU-0): DFP-1: disconnected
[ 337.432] (–) NVIDIA(GPU-0): DFP-1: Internal TMDS
[ 337.432] (–) NVIDIA(GPU-0): DFP-1: 165.0 MHz maximum pixel clock
[ 337.432] (–) NVIDIA(GPU-0):
[ 341.574] (–) NVIDIA(GPU-0): DELL U2414H (DFP-1): connected
[ 341.574] (–) NVIDIA(GPU-0): DELL U2414H (DFP-1): Internal TMDS
[ 341.574] (–) NVIDIA(GPU-0): DELL U2414H (DFP-1): 165.0 MHz maximum pixel clock
[ 341.574] (–) NVIDIA(GPU-0):
[ 341.576] (–) NVIDIA(GPU-0): DFP-0: disconnected
[ 341.576] (–) NVIDIA(GPU-0): DFP-0: Internal DisplayPort
[ 341.576] (–) NVIDIA(GPU-0): DFP-0: 2380.0 MHz maximum pixel clock
[ 341.576] (–) NVIDIA(GPU-0):
[ 341.673] (–) NVIDIA(GPU-0): DELL U2414H (DFP-1): connected
[ 341.673] (–) NVIDIA(GPU-0): DELL U2414H (DFP-1): Internal TMDS
[ 341.673] (–) NVIDIA(GPU-0): DELL U2414H (DFP-1): 165.0 MHz maximum pixel clock
[ 341.673] (–) NVIDIA(GPU-0):
[ 341.773] (II) NVIDIA(0): Setting mode “DP-1: nvidia-auto-select @1920x1080 +0+0 {ViewPortIn=1920x1080, ViewPortOut=1920x1080+0+0}”
[ 341.952] (–) NVIDIA(GPU-0): DFP-0: disconnected
[ 341.952] (–) NVIDIA(GPU-0): DFP-0: Internal DisplayPort
[ 341.952] (–) NVIDIA(GPU-0): DFP-0: 2380.0 MHz maximum pixel clock
[ 341.953] (–) NVIDIA(GPU-0):
[ 342.050] (–) NVIDIA(GPU-0): DELL U2414H (DFP-1): connected
[ 342.050] (–) NVIDIA(GPU-0): DELL U2414H (DFP-1): Internal TMDS
[ 342.050] (–) NVIDIA(GPU-0): DELL U2414H (DFP-1): 165.0 MHz maximum pixel clock
[ 342.050] (–) NVIDIA(GPU-0):

504566020 · April 6, 2023, 7:02am

接入U2414H，并且重启的话，屏幕没有任何显示，完全是黑的也不闪烁。
拿出如下Xorg日志。
U2414H-Xorg.0.log (59.7 KB)

WayneWWW · April 6, 2023, 8:17am

Hi,

請問一下, 你知道HDMI要支援的話要改device tree這件事嗎

我看了一下你的xorg log,看起來好像還在用DP的設定…

504566020 · April 6, 2023, 8:27am

这个我不知道要怎么改DT。
但是请看我这一次的操作，Hdmi doesn’t work for some monitors ,Discovering Again - #14 by 504566020
这次的是先接上了HDMI，然后reboot的，没有热拔插HDMI。这次应该是使用了HDMI的接口的。

那次显示使用的是DP接口的（Hdmi doesn’t work for some monitors ,Discovering Again - #13 by 504566020
是因为，我热拔插了HDMI，换到了U2414上，可能本身操作就不正确。

这俩个显示器，都是dell的，并且，都是通过HDMI接入的，一个不显示，一个可以显示。如果是DT配置的问题，我觉得应该是俩个显示器，都不能正确显示。

WayneWWW · April 6, 2023, 8:31am

Hi,

如同我前面說的, Orin的邏輯跟Xavier完全不一樣. Orin的display driver在你設置在DP mode的狀況下依然可以跑部份的HDMI 螢幕. 所以才有很多人誤以為自己不用改設定…

https://docs.nvidia.com/jetson/archives/r35.3.1/DeveloperGuide/text/SD/Kernel/DisplayConfigurationAndBringUp/OrinDisplayconfig.html

如果你沒有改任何東西, 那基本上我們就不用花時間討論你的測試手法或是螢幕有沒有問題.
預設的狀況就是沒辦法完整支援HDMI. 麻煩先去改DT.

WayneWWW · April 6, 2023, 8:35am

我有放一份其他用戶enable HDMI的過程在FAQ, 可以參考

→ Q: How to enable HDMI on Orin AGX if I design a custom board?

linuxdev · April 7, 2023, 1:11am

I want to point out that if you edit file “/etc/X11/Xorg.conf”, and find Section "Device", then you can add a line to get the driver to tell you about every mode it sees from the monitor’s EDID:

Section "Device"
   Option "ModeDebug"
....

Then, find the correct log during a boot via:
ls -ltr /var/log/Xorg.*.log | tail -n 1

Post that log after the Xorg.conf edit. It should tell you if the issue is related to EDID and modes. If not, then you can bet on the device tree being wrong for that format of display output (and this is likely to need edits if the carrier board is slightly different for display hardware).

504566020 · April 7, 2023, 2:19am

Hi,
the log
Xorg.0 (2).log (748.6 KB)

504566020 · April 7, 2023, 2:20am

Hi thanks:
i will do it ,next week.