drm/amd/display: change dc stream color settings only in atomic commit

Don't update DC stream color components during atomic check. The driver
will continue validating the new CRTC color state but will not change DC
stream color components. The DC stream color state will only be
programmed at commit time in the `atomic_setup_commit` stage.

It fixes gamma LUT loss reported by KDE users when changing brightness
quickly or changing Display settings (such as overscan) with nightlight
on and HDR. As KWin can do a test commit with color settings different
from those that should be applied in a non-test-only commit, if the
driver changes DC stream color state in atomic check, this state can be
eventually HW programmed in commit tail, instead of the respective state
set by the non-blocking commit.

Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4444
Reported-by: Xaver Hugl <xaver.hugl@gmail.com>
Signed-off-by: Melissa Wen <mwen@igalia.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
index c41c0ee4687f..009f206226f0 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
@@ -1054,6 +1054,8 @@ void amdgpu_dm_init_color_mod(void);
 int amdgpu_dm_create_color_properties(struct amdgpu_device *adev);
 int amdgpu_dm_verify_lut_sizes(const struct drm_crtc_state *crtc_state);
 int amdgpu_dm_update_crtc_color_mgmt(struct dm_crtc_state *crtc);
+int amdgpu_dm_check_crtc_color_mgmt(struct dm_crtc_state *crtc,
+				    bool check_only);
 int amdgpu_dm_update_plane_color_mgmt(struct dm_crtc_state *crtc,
 				      struct drm_plane_state *plane_state,
 				      struct dc_plane_state *dc_plane_state);