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8f959d37c1
Some shimmer/colorful points appears when using the steamOS color pipeline for HDR on gaming with DCN32. These points look like black values being wrongly mapped to red/blue/green values. It was caused because the number of hw points in regular LUTs and in a shaper LUT was treated as the same. DCN3+ regular LUTs have 257 bases and implicit deltas (i.e. HW calculates them), but shaper LUT is a special case: it has 256 bases and 256 deltas, as in DCN1-2 regular LUTs, and outputs 14-bit values. Fix that by setting by decreasing in 1 the number of HW points computed in the LUT segmentation so that shaper LUT (i.e. fixpoint == true) keeps the same DCN10 CM logic and regular LUTs go with `hw_points + 1`. CC: Krunoslav Kovac <Krunoslav.Kovac@amd.com> Fixes:4d5fd3d08e("drm/amd/display: PQ tail accuracy") Signed-off-by: Melissa Wen <mwen@igalia.com> Reviewed-by: Alex Hung <alex.hung@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit5006505b19)