Re: [PATCH] drm/amd/display: pull colorops into state when recreating a plane

Reviewed-by: Alex Hung <[email protected]>

On 8/25/26 09:35, Harry Wentland wrote:
> [Why]
> When should_reset_plane() forces a plane's dc_plane_state to be
> recreated (e.g. on every ALLOW_MODESET commit on DCN < 3.2),
> fill_dc_plane_attributes() re-derives the plane's color pipeline from
> the DRM colorop states. The per-stage helpers look up each colorop
> with for_each_new_colorop_in_state(), which only iterates colorops
> attached to the current commit. If userspace didn't touch color in
> that commit the colorops are absent, so the fixed matrix (YUV->RGB),
> shaper, 3D LUT and regamma all silently fall back to bypass. This
> corrupts the plane's colors - e.g. an HDR P010 video losing its
> color-space conversion - until the pipeline happens to be re-committed.
> 
> [How]
> When recreating a plane that has an active color_pipeline, call
> drm_atomic_add_affected_colorops() so the plane's colorops are pulled
> into the commit and the derivation sees the current pipeline instead
> of defaulting every stage to bypass. This mirrors what the core
> already does on a modeset via drm_atomic_add_affected_planes().
> 
> Assisted-by: Copilot:claude-opus-4.8
> Signed-off-by: Harry Wentland <[email protected]>
> ---
>   drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 13 +++++++++++++
>   1 file changed, 13 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 49f1a22f2888..4ee677f5b8b7 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -6337,6 +6337,19 @@ static int dm_update_plane_state(struct dc *dc,
>   		if (ret)
>   			goto out;
>   
> +		/*
> +		 * Recreating the plane re-derives its DC color pipeline from the
> +		 * colorop states in this commit. Pull the plane's colorops in so
> +		 * the derivation sees the current pipeline; otherwise every stage
> +		 * silently defaults to bypass (dropping YUV->RGB, shaper, 3D LUT
> +		 * and regamma) when userspace didn't touch color in this commit.
> +		 */
> +		if (new_plane_state->color_pipeline) {
> +			ret = drm_atomic_add_affected_colorops(state, plane);
> +			if (ret)
> +				goto out;
> +		}
> +
>   		WARN_ON(dm_new_plane_state->dc_state);
>   
>   		dc_new_plane_state = dc_create_plane_state(dc);