drm/amd: use fixed dsc bits-per-pixel from edid

VESA vendor header from DisplayID spec may contain fixed bit per pixel
rate, it should be used by drm driver for the modes that declare
they are only supported with the declared fixed bits per pixel value.

Signed-off-by: Yaroslav Bolyukin <iam@lach.pw>
Reviewed-by: Wayne Lin <Wayne.Lin@amd.com>

Author: CertainLach

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -6804,6 +6804,11 @@ static void fill_stream_properties_from_drm_display_mode(
 
 	stream->output_color_space = get_output_color_space(timing_out, connector_state);
 	stream->content_type = get_output_content_type(connector_state);
+
+	/* DisplayID Type VII pass-through timings. */
+	if (mode_in->dsc_passthrough_timings_support && info->dp_dsc_bpp_x16 != 0) {
+		stream->timing.dsc_fixed_bits_per_pixel_x16 = info->dp_dsc_bpp_x16;
+	}
 }
 
 static void fill_audio_info(struct audio_info *audio_info,
@@ -7262,6 +7267,7 @@ create_stream_for_sink(struct drm_connector *connector,
 	struct drm_display_mode mode;
 	struct drm_display_mode saved_mode;
 	struct drm_display_mode *freesync_mode = NULL;
+	struct drm_display_mode *dsc_passthru_mode = NULL;
 	bool native_mode_found = false;
 	bool recalculate_timing = false;
 	bool scale = dm_state->scaling != RMX_OFF;
@@ -7353,6 +7359,16 @@ create_stream_for_sink(struct drm_connector *connector,
 		}
 	}
 
+	list_for_each_entry(dsc_passthru_mode, &connector->modes, head) {
+		if (dsc_passthru_mode->hdisplay == mode.hdisplay &&
+		    dsc_passthru_mode->vdisplay == mode.vdisplay &&
+		    drm_mode_vrefresh(dsc_passthru_mode) == mode_refresh) {
+			mode.dsc_passthrough_timings_support =
+				dsc_passthru_mode->dsc_passthrough_timings_support;
+			break;
+		}
+	}
+
 	if (recalculate_timing)
 		drm_mode_set_crtcinfo(&saved_mode, 0);