Looks like this is a bug in DRM itself with the parsing.

[    1.325111] [drm] parse error at position 12 in video mode '1920x1080@59.94'
[    1.335096] [drm:dc_link_detect [amdgpu]] *ERROR* No EDID read.

It's hitting the "." as part of the video mode and erroring out because DRM
doesn't consider it a valid character.