drm/amd/display: Allow spatial dither to 10 bpc on all DCE

Spatial dithering to 10 bpc depth was disabled for all DCE's.

Testing on DCE-8.3 and DCE-11.2 did not show any obvious ill
effects, but a measureable precision improvement (via colorimeter)
when displaying a fp16 framebuffer to a 10 bpc DP or HDMI connected
HDR-10 monitor.

v2: enable it for all DCEs (Alex)

Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Cc: Alex Deucher <alexdeucher@gmail.com>
Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com> (v2)
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_opp.c b/drivers/gpu/drm/amd/display/dc/dce/dce_opp.c
index 4600231..895b015 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dce/dce_opp.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dce_opp.c
@@ -216,9 +216,7 @@ static void set_spatial_dither(
        REG_UPDATE(FMT_BIT_DEPTH_CONTROL,
                FMT_TEMPORAL_DITHER_EN, 0);
 
-       /* no 10bpc on DCE11*/
-       if (params->flags.SPATIAL_DITHER_ENABLED == 0 ||
-               params->flags.SPATIAL_DITHER_DEPTH == 2)
+       if (params->flags.SPATIAL_DITHER_ENABLED == 0)
                return;
 
        /* only use FRAME_COUNTER_MAX if frameRandom == 1*/