drm/amd/display: fix default dithering

bug: default is mapped to no dithering.

default to spatial dithering based on color depth
Signed-off-by: Tony Cheng <tony.cheng@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc.c

@@ -341,23 +341,9 @@ void set_dither_option(struct dc_stream_state *stream,
 		return;
 	if (option > DITHER_OPTION_MAX)
 		return;
-	if (option == DITHER_OPTION_DEFAULT) {
-		switch (stream->timing.display_color_depth) {
-		case COLOR_DEPTH_666:
-			stream->dither_option = DITHER_OPTION_SPATIAL6;
-			break;
-		case COLOR_DEPTH_888:
-			stream->dither_option = DITHER_OPTION_SPATIAL8;
-			break;
-		case COLOR_DEPTH_101010:
-			stream->dither_option = DITHER_OPTION_SPATIAL10;
-			break;
-		default:
-			option = DITHER_OPTION_DISABLE;
-		}
-	} else {
+
 	stream->dither_option = option;
-	}
+
 	resource_build_bit_depth_reduction_params(stream,
 				&params);
 	stream->bit_depth_params = params;

drivers/gpu/drm/amd/display/dc/core/dc_resource.c

@@ -2607,6 +2607,22 @@ void resource_build_bit_depth_reduction_params(struct dc_stream_state *stream,
 
 	memset(fmt_bit_depth, 0, sizeof(*fmt_bit_depth));
 
+	if (option == DITHER_OPTION_DEFAULT) {
+		switch (stream->timing.display_color_depth) {
+		case COLOR_DEPTH_666:
+			option = DITHER_OPTION_SPATIAL6;
+			break;
+		case COLOR_DEPTH_888:
+			option = DITHER_OPTION_SPATIAL8;
+			break;
+		case COLOR_DEPTH_101010:
+			option = DITHER_OPTION_SPATIAL10;
+			break;
+		default:
+			option = DITHER_OPTION_DISABLE;
+		}
+	}
+
 	if (option == DITHER_OPTION_DISABLE)
 		return;
 

drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c

@@ -1104,15 +1104,11 @@ static enum dc_status apply_single_controller_ctx_to_hw(
 		stream->timing.timing_3d_format != TIMING_3D_FORMAT_NONE);
 
 
-/*vbios crtc_source_selection and encoder_setup will override fmt_C*/
-	if (pipe_ctx->stream->signal != SIGNAL_TYPE_EDP &&
-		pipe_ctx->stream->signal != SIGNAL_TYPE_LVDS) {
-	/*for embedded panel, don't override VBIOS's setting*/
 	pipe_ctx->stream_res.opp->funcs->opp_program_fmt(
 		pipe_ctx->stream_res.opp,
 		&stream->bit_depth_params,
 		&stream->clamping);
-	}
+
 	if (dc_is_dp_signal(pipe_ctx->stream->signal))
 		pipe_ctx->stream_res.stream_enc->funcs->dp_set_stream_attribute(
 			pipe_ctx->stream_res.stream_enc,