[PATCH v2 3/4] drm/amd/display: Add handling for new "force color format" property

[Andri Yngvason]

From: Werner Sembach <wse at tuxedocomputers.com>

This commit implements the "force color format" drm property for the
AMD GPU driver.

Signed-off-by: Werner Sembach <wse at tuxedocomputers.com>
Co-Developed-by: Andri Yngvason <andri at yngvason.is>
Signed-off-by: Andri Yngvason <andri at yngvason.is>
Tested-by: Andri Yngvason <andri at yngvason.is>
---

Changes in v2:
 - Renamed to "force color format" from "preferred color format"
 - Modeset will fail if color format cannot be satisfied

---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 63 ++++++++++++++++---
 .../display/amdgpu_dm/amdgpu_dm_mst_types.c   |  4 ++
 2 files changed, 60 insertions(+), 7 deletions(-)

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 cc4d1f7f97b98..26c4260c78d7b 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -5573,15 +5573,32 @@ static void fill_stream_properties_from_drm_display_mode(
 	timing_out->h_border_right = 0;
 	timing_out->v_border_top = 0;
 	timing_out->v_border_bottom = 0;
-	/* TODO: un-hardcode */
-	if (drm_mode_is_420_only(info, mode_in)
-			|| (drm_mode_is_420_also(info, mode_in) && aconnector->force_yuv420_output))
+
+	if (connector_state
+			&& (connector_state->force_color_format == DRM_COLOR_FORMAT_YCBCR420
+			|| aconnector->force_yuv420_output) && drm_mode_is_420(info, mode_in))
 		timing_out->pixel_encoding = PIXEL_ENCODING_YCBCR420;
-	else if ((connector->display_info.color_formats & DRM_COLOR_FORMAT_YCBCR444)
-			&& stream->signal == SIGNAL_TYPE_HDMI_TYPE_A)
+	else if (connector_state
+			&& connector_state->force_color_format == DRM_COLOR_FORMAT_YCBCR444
+			&& connector->display_info.color_formats & DRM_COLOR_FORMAT_YCBCR444)
 		timing_out->pixel_encoding = PIXEL_ENCODING_YCBCR444;
-	else
+	else if (connector_state
+			&& connector_state->force_color_format == DRM_COLOR_FORMAT_RGB444
+			&& !drm_mode_is_420_only(info, mode_in))
 		timing_out->pixel_encoding = PIXEL_ENCODING_RGB;
+	else
+		/*
+		 * connector_state->force_color_format not possible
+		 * || connector_state->force_color_format == 0 (auto)
+		 * || connector_state->force_color_format == DRM_COLOR_FORMAT_YCBCR422
+		 */
+		if (drm_mode_is_420_only(info, mode_in))
+			timing_out->pixel_encoding = PIXEL_ENCODING_YCBCR420;
+		else if ((connector->display_info.color_formats & DRM_COLOR_FORMAT_YCBCR444)
+				&& stream->signal == SIGNAL_TYPE_HDMI_TYPE_A)
+			timing_out->pixel_encoding = PIXEL_ENCODING_YCBCR444;
+		else
+			timing_out->pixel_encoding = PIXEL_ENCODING_RGB;
 
 	timing_out->timing_3d_format = TIMING_3D_FORMAT_NONE;
 	timing_out->display_color_depth = convert_color_depth_from_display_info(
@@ -6685,6 +6702,33 @@ static enum dc_status dm_validate_stream_and_context(struct dc *dc,
 	return dc_result;
 }
 
+static enum dc_status
+dm_validate_stream_color_format(const struct drm_connector_state *drm_state,
+				const struct dc_stream_state *stream)
+{
+	if (!drm_state->force_color_format)
+		return DC_OK;
+
+	enum dc_pixel_encoding encoding = PIXEL_ENCODING_UNDEFINED;
+	switch (drm_state->force_color_format) {
+	case DRM_COLOR_FORMAT_RGB444:
+		encoding = PIXEL_ENCODING_RGB;
+		break;
+	case DRM_COLOR_FORMAT_YCBCR444:
+		encoding = PIXEL_ENCODING_YCBCR444;
+		break;
+	case DRM_COLOR_FORMAT_YCBCR422:
+		encoding = PIXEL_ENCODING_YCBCR422;
+		break;
+	case DRM_COLOR_FORMAT_YCBCR420:
+		encoding = PIXEL_ENCODING_YCBCR420;
+		break;
+	}
+
+	return encoding == stream->timing.pixel_encoding ?
+	       DC_OK : DC_UNSUPPORTED_VALUE;
+}
+
 struct dc_stream_state *
 create_validate_stream_for_sink(struct amdgpu_dm_connector *aconnector,
 				const struct drm_display_mode *drm_mode,
@@ -6717,6 +6761,9 @@ create_validate_stream_for_sink(struct amdgpu_dm_connector *aconnector,
 		if (dc_result == DC_OK)
 			dc_result = dm_validate_stream_and_context(adev->dm.dc, stream);
 
+		if (dc_result == DC_OK)
+			dc_result = dm_validate_stream_color_format(drm_state, stream);
+
 		if (dc_result != DC_OK) {
 			DRM_DEBUG_KMS("Mode %dx%d (clk %d) failed DC validation with error %d (%s)\n",
 				      drm_mode->hdisplay,
@@ -7512,8 +7559,10 @@ void amdgpu_dm_connector_init_helper(struct amdgpu_display_manager *dm,
 				adev->mode_info.underscan_vborder_property,
 				0);
 
-	if (!aconnector->mst_root)
+	if (!aconnector->mst_root) {
 		drm_connector_attach_max_bpc_property(&aconnector->base, 8, 16);
+		drm_connector_attach_force_color_format_property(&aconnector->base);
+	}
 
 	aconnector->base.state->max_bpc = 16;
 	aconnector->base.state->max_requested_bpc = aconnector->base.state->max_bpc;
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
index 941e96f100f4e..437d50f53eb97 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
@@ -601,6 +601,10 @@ dm_dp_add_mst_connector(struct drm_dp_mst_topology_mgr *mgr,
 	if (connector->max_bpc_property)
 		drm_connector_attach_max_bpc_property(connector, 8, 16);
 
+	connector->force_color_format_property = master->base.force_color_format_property;
+	if (connector->force_color_format_property)
+		drm_connector_attach_force_color_format_property(&aconnector->base);
+
 	connector->vrr_capable_property = master->base.vrr_capable_property;
 	if (connector->vrr_capable_property)
 		drm_connector_attach_vrr_capable_property(connector);
-- 
2.43.0