[Resolved] Black screen after update today

[Annie UK]

I did an apt Update and apt upgrade this evening and after a reboot I just got a black screen

I have to change
dtoverlay=vc4-kms-v3d
to
dtoverlay=vc4-fkms-v3d
in config.txt
I also added:
hdmi_group=1
hdmi_mode=16
To the end of config.txt

Is there a way to fix the screen issue without resulting to the above config.txt changes

I've been running this set up for well over a year with the same setting, is this just a dogy update that'll be fixed in the future?

[terribleted]

i believe that the issue is that SOME screens do not "properly" respond to the EDID data probe the PI sends to figure out what resolution to set.
i think it only happens with Some displays....
I don't have this issue with any of my monitors (or my TV) so i cant say for sure.
I'd say to try using xrandr in a terminal, (under FKMS) see what that returns as supported resolutions, then try to set it manually, switching back to the KMS driver to see if it works..

I'm not expecting this to be considered a "bug" (by PI staff) as it appears to happen only to Some displays... maybe they send malformed or incomplete EDID data? they might improve the results in KMS, but i would not expect it to get the same priorities as a "bug".
of course, that my (uninformed) opinion. PI staff may see it differently...

[Annie UK]

I've been using the same ASUS VG278 monitor and only the last update has caused the issue

xrandr output:

Code: Select all

Screen 0: minimum 16 x 16, current 1920 x 1080, maximum 32767 x 32767
XWAYLAND0 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 600mm x 340mm
   1920x1080     59.96*+
   1440x1080     59.99  
   1400x1050     59.98  
   1280x1024     59.89  
   1280x960      59.94  
   1152x864      59.96  
   1024x768      59.92  
   800x600       59.86  
   640x480       59.38  
   320x240       59.52  
   1680x1050     59.95  
   1440x900      59.89  
   1280x800      59.81  
   720x480       59.71  
   640x400       59.95  
   320x200       58.96  
   1600x900      59.95  
   1368x768      59.88  
   1280x720      59.86  
   1024x576      59.90  
   864x486       59.92  
   720x400       59.55  
   640x350       59.77  

[terribleted]

here is how to force the new driver to use a specific resolution
(from other posts)

- manually set resolution
Try adding hdmi_ignore_edid=0xa5000080 to config.txt and setting the resolution manually (in cmdline.txt).
in /boot/cmdline.txt (add to the end of the line, NOT a new line)
video=HDMI-A-1:1024x768@60D
(Above sets 1024x768 at 60hz, Digital (hdmi))

i should note that i could never get the PI to ignore my EDID data.... but others have said that the above method works.

also, you can use xrandr to set a resolution:
xrandr -s 1920x1080 (set video mode to 1920x1080)

i have only played with this a little, as all my displays do not exhibit the problem...

[Annie UK]

With those changes I still get a blank screen.

I think they have broken dtoverlay=vc4-kms-v3d as the only way I can get my monitor to wake is by using dtoverlay=vc4-fkms-v3d (Fake KMS)

[dom]

Try adding hdmi_ignore_edid=0xa5000080 to config.txt and setting the resolution manually (in cmdline.txt).
in /boot/cmdline.txt (add to the end of the line, NOT a new line)
video=HDMI-A-1:1024x768@60D
(Above sets 1024x768 at 60hz, Digital (hdmi))

i should note that i could never get the PI to ignore my EDID data.... but others have said that the above method works.

In general hdmi settings in config.txt only affect the firmware driver (fkms), not the kernel driver (kms).
cmdline.txt option are for the kernel.

Have a read here for how to force a different edid with kms.

[terribleted]

Thanks @dom !
now it makes sense.

[iSancheZ]

Hi. I have the same problem after update and nothing helps me...

[dom]

Hi. I have the same problem after update and nothing helps me...

Are you running Ubuntu on Pi4, and have a blank screen. And switching from kms to fkms driver avoids the blank screen?

[iSancheZ]

Are you running Ubuntu on Pi4, and have a blank screen. And switching from kms to fkms driver avoids the blank screen?

Ubuntu 22.10 with latest updates on Pi400. Yes, only switching from kms to fkms driver resolve problem.

[dom]

If you have a spare sdcard, please test latest RpiOS bullseye and report if the same issue happens.
If it does, then run rpi-update and report if it happens.

If either of these work, then it means recent downstream kernel patches (they will be currently in process of being submitted upstream)
are required by Ubuntu, and it's best to let Ubuntu devs know.

[kerry_s]

best to stick with ubuntu 22.04lts

[fprietog]

Take a look to this bug and it's fix:
https://bugs.launchpad.net/ubuntu/kinet ... ug/2007259

[kerry_s]

22.10 is still all kinds of buggy.

22.04lts works great though.

[Annie UK]

Looks like this is resolved in the next kernel update

[Annie UK]

New Kernel just release and I can confirm they have fixed the KMS driver

[Mitya Cohen]

Just installed the new image of raspbian with the Pi imager. It says it has to be updated. But as soon as I start update it shows me the black screen. Is there any working solution for this so far?

[Annie UK]

Change the display driver in config.txt