Question about HF-EEODB EDID extension override handling

Question about HF-EEODB EDID extension override handling

[Timo Prömer]

Hi,

I am trying to get my Samsung Odyssey Neo G8 to run on 3840x2160@240Hz
over HDMI 2.1 (Linux 7.2-rc2), but that mode does not show up.

I noticed that the EDID only contains block 0 and 1,
even though the HF-EEODB specifies an extension block count of 3.

From my reading, the EDID parsing code in 'drivers/gpu/drm/drm_edid.c' 
does respect this override as far as i can tell.
However I also found some code that appears to be copying / truncating the 
EDID in 'drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c:1208'
(function: 'dm_helpers_read_local_edid') without accounting for this override.

I am new to kernel-level development, so I apologize in advance if I 
am misunderstanding the intended flow here. Could this be the reason for
my incomplete EDID? The kernel does not log any EDID-related errors or
warnings, so I am not sure whether this is expected behavior or a bug.

Please keep me on Cc; I am not subscribed to the list.

Thanks,
Timo Prömer