Some progress...
When the vc4-kms-v3d driver is enabled then:
- trying to set a resolution through Preferences->Raspberry Pi Configuration results in an unresponsive systsem
- trying to set a resolution by editing /boot/config.txt works for the video signal, but the desktop and vnc get a different resolution
With the vc4-fkms-vc3 driver (the 'fake kms one'):
- I can set a resolution, which is honoured both for the video signal and the desktop resolution
- GLXgears gives a good performance
However I can not yet get a desktop resolution higher then 1920x1280.
I've tried a custom mode, e.g. for use on an ipad pro vncviewer
hdmi_cvt=2728 2046 15 1 0 0 1
hdmi_group=2
hdmi_mode=87
Booting headless, tvservice reports DMT (87), but the vncdesktop is 1920x1280 and actually quite slow
When the vc4-kms-v3d driver is enabled then:
- trying to set a resolution through Preferences->Raspberry Pi Configuration results in an unresponsive systsem
- trying to set a resolution by editing /boot/config.txt works for the video signal, but the desktop and vnc get a different resolution
With the vc4-fkms-vc3 driver (the 'fake kms one'):
- I can set a resolution, which is honoured both for the video signal and the desktop resolution
- GLXgears gives a good performance
However I can not yet get a desktop resolution higher then 1920x1280.
I've tried a custom mode, e.g. for use on an ipad pro vncviewer
hdmi_cvt=2728 2046 15 1 0 0 1
hdmi_group=2
hdmi_mode=87
Booting headless, tvservice reports DMT (87), but the vncdesktop is 1920x1280 and actually quite slow