There was regression on drm-tip CI_DRM_6936 where these patches were on that build: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_6936/git-log-oneline.txt.
Previous build was https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_6935/git-log-oneline.txt that has working colors
For this there is already revert: https://patchwork.freedesktop.org/series/67174/
and with that screen is again normal. Tested on TGL.
1b8588741fdc ("Revert "drm/i915/color: Extract icl_read_luts()"")