EDID read issue on kernel 6.12 - missing 1280x800 mode (CB2)

[mecho]

I'm using Armbian with kernel 6.12 on a  (CB2) device. When I connect my monitor via HDMI, the EDID is successfully read and it includes both 1920x1080 and 1280x800 as supported resolutions.

However, only 1920x1080 appears in the available display modes. The 1280x800 mode is missing, even though it is clearly listed in the EDID.

[anarsoul]

This mode needs 80MHz pixel clock which is not in the table for clk-rk3568.c driver. You need a patch similar to https://lkml.org/lkml/2025/3/18/1337 to add this rate.

 

FWIW 1280x800@63.59Hz isn't a very common mode