N2 with Ubuntu - dark screen after boot

[blissarts]

Hello,
I have gotten my Odroid N2 last week and it works without any issue with the delivered CoreElec SD card.
However I want to use Ubuntu (image provided by HK) with my USB SSD.
It is booting up and I can work via ssh without problems but my TV screen stays dark. I see that the TV is switching off when I shut the odroid down so some signal is coming through the HDMI.
I can also see proper screen output in the SPI (when selecting the SSD for boot).
Tried now both the minimal latest ubuntu image with Kodi installed and the one with Mate Desktop. Same for both.
Also switching off the auto detection and defining a resolution/frequency via boot.ini (that I know is working) did bring me further.
It must be some kind of configuration issue I think but I don't know where to look further.

Hope someone can help me out.

Thanks, BR

[odroid]

Do you have a HDR capable 4K TV?
What is the brand/model name of your display?

[blissarts]

Thanks for the fast reply.

No it's a 1080p capable model:
Toshiba 40TL968G

[odroid]

Post your modified boot.ini file and we will try to find a possible solution.

[blissarts]

Hi,
I have tried several tweaks, but these two versions I still have that both did not work.
I want to highlight again that the screen and HW in general is working well since the default SD card Coreelec was working well.

Thank you, BR

[odroid]

I couldn't find any clue in your boot.ini files.

I hope @joy or @tobetter can help you.

[joy]

Hi @blissarts,
I also checked your boot.ini files but, nothing strange because it works well when you try CoreElec from SD card booting.

1. Can you check if you have a normal display, Petitboot menu without USB storage connected?
If so, please share petitboot version information.

2. And I will reproduce it with my test environment, so could you share Coreelec image version that you're using?

3. One more question..
Is the HDMI cable kept connected during boot after power-on?

[blissarts]

thx for the replay joy.
I want to highlight that the boot.ini is differnt for CoreElec as I have received it from Hardkernel together with the N2. I did not alter it by myself. And for the HK Ubuntu image the boot.ini is also provided by default (posted above). I am really not used to the bootloader config stuff...

1. Petitboot menu is shown at every startup. Version 20191213 (original version)
2. As I did not flash it myself I don't know. I think we need to ask the Hardkernel guy who prepared it
3. yes. But I have tried both, keep it connected and connect it after startup

One very strange thing after I have done a full re-install with the ubuntu minimal: Once I could see kodi normally when starting it via kodi-standalone via ssh (because my actual screen is dark) after deleting the Addons27.db (I have found that somewhere else). But after that it was not reproducible any more so still dark screen.

[blissarts]

I tried two more things:
1) install Debian Buster to my SSD => same issue as before
2) install Debian Buster to the SD card => it's working

So where is it going wrong when booting from SSD?
I mean the booting itself is OK since I can connect via SSH and do everything but just the difference for me seems to be the HDMI output.

[joy]

Thank you for sharing the information, @bilssarts,
I will try to reproduce it early next week.

And can I ask one more?
To synchronize my HDMI timing property with your monitor's spec, could you share the following debug files?
(1) edid.bin
(2) display.bin

You can get the files from SD card booting.
- Boot from SD card
- "display_autodetect" option should be set as "true"

Code: Select all

setenv display_autodetect "true"

- The files will be generated in fat filesystem of your SD Card.

[blissarts]

Hi,

here are the files:

[joy]

Thanks for sharing it.
Let me check this issue for a couple of days.

[blissarts]

Hello
is there any conclusion on this topic?
Seems i have crashed my so far well working Debian installation and now i am considering to go back to ubuntu if there is a solution to this issue

Thanks

[odroid]

We forgot this thread and sorry about that.

Which Debian OS image did you use?
Is it @tobetter's Netboot Installer?

[blissarts]

No problem. This one worked for me: viewtopic.php?f=179&t=35658

[eddiepropane]

Hi and sorry to jump on this thread but I am having similar boot to black screen issues on an older 1080p set.

I'd posted in another thread but was looking through the petitboot thread and came across this thread which if display specific and was wondering if anyone could help with my situation.

I have the N2 connected to 1080p LGTV - LG 47LW450U - edid.bin and display.bin attached.

I cannot boot any OS from petitboot from emmc, usd (SanDisk) or usb without losing the display and having to cycle inputs, if the display sleeps or the TV is on standby then it takes a reboot of the box to get the display back.

I also see issues on a straight boot to Android where it will get past the Android bootplash and as the leanback launcher appears the screen sleeps and a power cycle is required, this is quite intermittent unlike petitboot so may be a separate issue.

The only option that works is autodetect false and voutmode dvi but this does not give me any sound.

This is using Android, Ubuntu, Armbian etc, going through all the troubleshooting options for Android I think I have tried all combinations of boot well now env.ini options suggested (autodetect, disablehpe, suspendphy etc.) with no success, all attached in a zip, I also tried using a modeline as when looking at the display.bin the 1080p string was different by 1 digit to the a 1080p example.

I have tried amending the uhd option in petitboot and also manual setting the resolution to 1080p50hz and 720p60hz to see if petitboot being a different resolution to the booting OS would trigger a display mode change but this also goes to no signal.

I do not have a compatible UART for the N2 but happy to get one shipped from odroid.uk if that will help out with any investigation required on my end

It think it is 100% related to the TV as I get no issues on a 1080p Samsung and a 4k Panasonic set.

Sorry for jumping in the thread but would be great if anyone could help with a fix if it is possible, thanks.

[joy]

Hi @eddiepropane,
Sorry for very late response.
We will reproduce this issue here using your information.

You have the same issue when you use Ubuntu image from petitboot, right?

[blissarts]

Correct.
Thanks for taking care.

[eddiepropane]

Hi @joy

Massive apologies from myself for the delayed response, I've subscribed to the thread but did must not have mail notifications setup, I get them for the Petitboot thread but not on this one!!

Yes I can confirm the issues are there using the most recent Ubuntu Mate image I could find (ubuntu-20.04-4.9-mate-odroid-n2-20200716.img.xz) and also the most recent Android image.

There must have been some changes to CoreELEC/EmuELEC as recent builds of those do not show using voutmode dvi, I now get an invalid format error from the TV.

Thanks again

[joy]

Hi @eddiepropane, @blissarts,
Thank you for your confirmation.
I could reproduce the dark screen issue here.
Once it's fixed, I will share the status.
I'm sorry for very late update.

[joy]

Hi @eddiepropane,

Can I ask your favor?

It looks the issue pattern with my environment is a bit different from @blissarts' and yours.

So to make sure and narrow the root cause,
when you're available, can you share "dmesg" log when you have the issue on Ubuntu with your LG monitor?

ex) 1080p60hz manual, HDMI mode case -> have dark screen issue

[joy]

Hello @eddiepropane, @blissarts,

[1]
Can you check the output from this sysfs node when you have no display issue?

Code: Select all

$ cat /sys/class/display/mode

[2]
And please share 'dmesg' output, too.

I doubt a part of hdmi hot plug logic and those information can help me to figure it out.