[PATCH 07/31] drm/amd/display: add mst port output bw check

[Rodrigo Siqueira]

From: hersen wu <hersenxs.wu at amd.com>

[Why]
when connect one 4k at 144hz dp to dsc mst hub, 4k at 144hz mode is in valid
mode list. but some mst hub port output bandwidth does not support
4k at 144hz.

[How]
add mst port output bandwidth checks, include full_pbn, branch max
throughput mps.

Reviewed-by: Jerry Zuo <Jerry.Zuo at amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira at amd.com>
Signed-off-by: hersen wu <hersenxs.wu at amd.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c |  8 +++--
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h |  3 +-
 .../display/amdgpu_dm/amdgpu_dm_mst_types.c   | 36 +++++++++++++++++++
 .../display/amdgpu_dm/amdgpu_dm_mst_types.h   |  4 +++
 4 files changed, 48 insertions(+), 3 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 c2fc32dac712..ea91149ec3e6 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -7259,7 +7259,11 @@ create_validate_stream_for_sink(struct amdgpu_dm_connector *aconnector,
 			break;
 		}
 
-		dc_result = dc_validate_stream(adev->dm.dc, stream);
+		if (stream->signal == SIGNAL_TYPE_DISPLAY_PORT_MST)
+			dc_result = dm_dp_mst_is_port_support_mode(aconnector, stream);
+
+		if (dc_result == DC_OK)
+			dc_result = dc_validate_stream(adev->dm.dc, stream);
 
 		if (dc_result != DC_OK) {
 			DRM_DEBUG_KMS("Mode %dx%d (clk %d) failed DC validation with error %d (%s)\n",
@@ -7559,7 +7563,7 @@ static void dm_encoder_helper_disable(struct drm_encoder *encoder)
 
 }
 
-static int convert_dc_color_depth_into_bpc (enum dc_color_depth display_color_depth)
+int convert_dc_color_depth_into_bpc(enum dc_color_depth display_color_depth)
 {
 	switch (display_color_depth) {
 		case COLOR_DEPTH_666:
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
index cbd2e8f2ae50..8241a3795762 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
@@ -583,7 +583,6 @@ struct amdgpu_dm_connector {
 	struct drm_dp_mst_port *port;
 	struct amdgpu_dm_connector *mst_port;
 	struct drm_dp_aux *dsc_aux;
-
 	/* TODO see if we can merge with ddc_bus or make a dm_connector */
 	struct amdgpu_i2c_adapter *i2c;
 
@@ -747,4 +746,6 @@ int dm_atomic_get_state(struct drm_atomic_state *state,
 struct amdgpu_dm_connector *
 amdgpu_dm_find_first_crtc_matching_connector(struct drm_atomic_state *state,
 					     struct drm_crtc *crtc);
+
+int convert_dc_color_depth_into_bpc(enum dc_color_depth display_color_depth);
 #endif /* __AMDGPU_DM_H__ */
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 d005bb6a2956..ee5d6fa34a6b 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
@@ -1353,4 +1353,40 @@ bool pre_validate_dsc(struct drm_atomic_state *state,
 
 	return (ret == 0);
 }
+
 #endif
+
+enum dc_status dm_dp_mst_is_port_support_mode(
+	struct amdgpu_dm_connector *aconnector,
+	struct dc_stream_state *stream)
+{
+	int bpp, pbn, branch_max_throughput_mps = 0;
+
+	/* check if mode could be supported within fUll_pbn */
+	bpp = convert_dc_color_depth_into_bpc(stream->timing.display_color_depth) * 3;
+	pbn = drm_dp_calc_pbn_mode(stream->timing.pix_clk_100hz / 10, bpp, false);
+	if (pbn > aconnector->port->full_pbn)
+		return DC_FAIL_BANDWIDTH_VALIDATE;
+
+	/* check is mst dsc output bandwidth branch_overall_throughput_0_mps */
+	switch (stream->timing.pixel_encoding) {
+	case PIXEL_ENCODING_RGB:
+	case PIXEL_ENCODING_YCBCR444:
+		branch_max_throughput_mps =
+			aconnector->dc_sink->dsc_caps.dsc_dec_caps.branch_overall_throughput_0_mps;
+		break;
+	case PIXEL_ENCODING_YCBCR422:
+	case PIXEL_ENCODING_YCBCR420:
+		branch_max_throughput_mps =
+			aconnector->dc_sink->dsc_caps.dsc_dec_caps.branch_overall_throughput_1_mps;
+		break;
+	default:
+		break;
+	}
+
+	if (branch_max_throughput_mps != 0 &&
+		((stream->timing.pix_clk_100hz / 10) >  branch_max_throughput_mps * 1000))
+		return DC_FAIL_BANDWIDTH_VALIDATE;
+
+	return DC_OK;
+}
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h
index 2e13027d9b88..b92a7c5671aa 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h
@@ -63,4 +63,8 @@ bool pre_validate_dsc(struct drm_atomic_state *state,
 		      struct dm_atomic_state **dm_state_ptr,
 		      struct dsc_mst_fairness_vars *vars);
 
+enum dc_status dm_dp_mst_is_port_support_mode(
+	struct amdgpu_dm_connector *aconnector,
+	struct dc_stream_state *stream);
+
 #endif
-- 
2.25.1