Re: [PATCH v2 31/34] drm/amd/display: set stream gamut remap matrix to MPC for DCN301

[Pekka Paalanen]

On Thu, 10 Aug 2023 15:03:11 -0100
Melissa Wen <mwen@xxxxxxxxxx> wrote:

> dc->caps.color.mpc.gamut_remap says there is a post-blending color block
> for gamut remap matrix for DCN3 HW family and newer versions. However,
> those drivers still follow DCN10 programming that remap stream
> gamut_remap_matrix to DPP (pre-blending).

That's ok only as long as CRTC degamma is pass-through. Blending itself
is a linear operation, so it doesn't matter if a matrix is applied to
the blending result or to all blending inputs. But you cannot move a
matrix operation to the other side of a non-linear operation, and you
cannot move a non-linear operation across blending.


Thanks,
pq

> To enable pre-blending and post-blending gamut_remap matrix supports at
> the same time, set stream gamut_remap to MPC and plane gamut_remap to
> DPP for DCN301 that support both.
> 
> It was tested using IGT KMS color tests for DRM CRTC CTM property and it
> preserves test results.
> 
> Signed-off-by: Melissa Wen <mwen@xxxxxxxxxx>
> ---
>  .../drm/amd/display/dc/dcn30/dcn30_hwseq.c    | 37 +++++++++++++++++++
>  .../drm/amd/display/dc/dcn30/dcn30_hwseq.h    |  3 ++
>  .../drm/amd/display/dc/dcn301/dcn301_init.c   |  2 +-
>  3 files changed, 41 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c
> index 4cd4ae07d73d..4fb4e9ec03f1 100644
> --- a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c
> +++ b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c
> @@ -186,6 +186,43 @@ bool dcn30_set_input_transfer_func(struct dc *dc,
>  	return result;
>  }
>  
> +void dcn30_program_gamut_remap(struct pipe_ctx *pipe_ctx)
> +{
> +	int i = 0;
> +	struct dpp_grph_csc_adjustment dpp_adjust;
> +	struct mpc_grph_gamut_adjustment mpc_adjust;
> +	int mpcc_id = pipe_ctx->plane_res.hubp->inst;
> +	struct mpc *mpc = pipe_ctx->stream_res.opp->ctx->dc->res_pool->mpc;
> +
> +	memset(&dpp_adjust, 0, sizeof(dpp_adjust));
> +	dpp_adjust.gamut_adjust_type = GRAPHICS_GAMUT_ADJUST_TYPE_BYPASS;
> +
> +	if (pipe_ctx->plane_state &&
> +	    pipe_ctx->plane_state->gamut_remap_matrix.enable_remap == true) {
> +		dpp_adjust.gamut_adjust_type = GRAPHICS_GAMUT_ADJUST_TYPE_SW;
> +		for (i = 0; i < CSC_TEMPERATURE_MATRIX_SIZE; i++)
> +			dpp_adjust.temperature_matrix[i] =
> +				pipe_ctx->plane_state->gamut_remap_matrix.matrix[i];
> +	}
> +
> +	pipe_ctx->plane_res.dpp->funcs->dpp_set_gamut_remap(pipe_ctx->plane_res.dpp,
> +							    &dpp_adjust);
> +
> +	memset(&mpc_adjust, 0, sizeof(mpc_adjust));
> +	mpc_adjust.gamut_adjust_type = GRAPHICS_GAMUT_ADJUST_TYPE_BYPASS;
> +
> +	if (pipe_ctx->top_pipe == NULL) {
> +		if (pipe_ctx->stream->gamut_remap_matrix.enable_remap == true) {
> +			mpc_adjust.gamut_adjust_type = GRAPHICS_GAMUT_ADJUST_TYPE_SW;
> +			for (i = 0; i < CSC_TEMPERATURE_MATRIX_SIZE; i++)
> +				mpc_adjust.temperature_matrix[i] =
> +					pipe_ctx->stream->gamut_remap_matrix.matrix[i];
> +		}
> +	}
> +
> +	mpc->funcs->set_gamut_remap(mpc, mpcc_id, &mpc_adjust);
> +}
> +
>  bool dcn30_set_output_transfer_func(struct dc *dc,
>  				struct pipe_ctx *pipe_ctx,
>  				const struct dc_stream_state *stream)
> diff --git a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.h b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.h
> index a24a8e33a3d2..cb34ca932a5f 100644
> --- a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.h
> +++ b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.h
> @@ -58,6 +58,9 @@ bool dcn30_set_blend_lut(struct pipe_ctx *pipe_ctx,
>  bool dcn30_set_input_transfer_func(struct dc *dc,
>  				struct pipe_ctx *pipe_ctx,
>  				const struct dc_plane_state *plane_state);
> +
> +void dcn30_program_gamut_remap(struct pipe_ctx *pipe_ctx);
> +
>  bool dcn30_set_output_transfer_func(struct dc *dc,
>  				struct pipe_ctx *pipe_ctx,
>  				const struct dc_stream_state *stream);
> diff --git a/drivers/gpu/drm/amd/display/dc/dcn301/dcn301_init.c b/drivers/gpu/drm/amd/display/dc/dcn301/dcn301_init.c
> index 257df8660b4c..81fd50ee97c3 100644
> --- a/drivers/gpu/drm/amd/display/dc/dcn301/dcn301_init.c
> +++ b/drivers/gpu/drm/amd/display/dc/dcn301/dcn301_init.c
> @@ -33,7 +33,7 @@
>  #include "dcn301_init.h"
>  
>  static const struct hw_sequencer_funcs dcn301_funcs = {
> -	.program_gamut_remap = dcn10_program_gamut_remap,
> +	.program_gamut_remap = dcn30_program_gamut_remap,
>  	.init_hw = dcn10_init_hw,
>  	.power_down_on_boot = dcn10_power_down_on_boot,
>  	.apply_ctx_to_hw = dce110_apply_ctx_to_hw,