• Krunoslav Kovac's avatar
    drm/amd/display: Optimize regamma calculations · 8f8372c7
    Krunoslav Kovac authored
    There are several optimizations:
    1) Use predefined SRGB, don't calculate. This is the most common case.
    2) Precompute HW X points at boot since they're fixed in ColModule
    3) Precompute PQ - it never changes and is very CPU intensive in fixed pt.
    4) Reduce number of points in ColModule to 512 (32x16) from 1024. This also
    requires reducing some regions for legacy DCEs to 16 pts at most.
    
    Performance
    1) is super-fast, build_output_tf is 1-2us, down from 25000-30000.
    Programming also fast since only one reg write.
    2)+3) gives build_output_tf for PQ in ~100us range, down from ~80000-110000
    2) + 4) results in slightly over 50% improvement. It gives an idea of the
    savings when we can't use SRGB or PQ table (e.g. sdr white level > 80).
    
    There's also a bit of refactoring: renaming some stuff that was misleading
    and removing a lot of magic numbers that novices might not be able to
    understand where they come from and what they mean.
    Signed-off-by: default avatarKrunoslav Kovac <Krunoslav.Kovac@amd.com>
    Reviewed-by: default avatarTony Cheng <Tony.Cheng@amd.com>
    Acked-by: default avatarHarry Wentland <harry.wentland@amd.com>
    Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
    8f8372c7
dcn10_dpp.c 13.6 KB