[PATCH v1] drm/amd/display: Add DP-HDMI PCON SST Support

[Fangzhi Zuo]

1. Parse DSC caps from PCON DPCD
2. Determine policy if decoding DSC at PCON
3. Enable/disable DSC at PCON

Signed-off-by: Fangzhi Zuo <Jerry.Zuo at amd.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 41 +++++++++++++++----
 .../amd/display/amdgpu_dm/amdgpu_dm_helpers.c | 13 +++++-
 2 files changed, 44 insertions(+), 10 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 9a1ac657faa2..9dbf6bf3f1c3 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -6047,10 +6047,12 @@ static void update_dsc_caps(struct amdgpu_dm_connector *aconnector,
 
 	if (aconnector->dc_link && (sink->sink_signal == SIGNAL_TYPE_DISPLAY_PORT ||
 		sink->sink_signal == SIGNAL_TYPE_EDP)) {
-		dc_dsc_parse_dsc_dpcd(aconnector->dc_link->ctx->dc,
-				      aconnector->dc_link->dpcd_caps.dsc_caps.dsc_basic_caps.raw,
-				      aconnector->dc_link->dpcd_caps.dsc_caps.dsc_branch_decoder_caps.raw,
-				      dsc_caps);
+		if (sink->link->dpcd_caps.dongle_type == DISPLAY_DONGLE_NONE ||
+			sink->link->dpcd_caps.dongle_type == DISPLAY_DONGLE_DP_HDMI_CONVERTER)
+			dc_dsc_parse_dsc_dpcd(aconnector->dc_link->ctx->dc,
+				aconnector->dc_link->dpcd_caps.dsc_caps.dsc_basic_caps.raw,
+				aconnector->dc_link->dpcd_caps.dsc_caps.dsc_branch_decoder_caps.raw,
+				dsc_caps);
 	}
 }
 
@@ -6120,6 +6122,8 @@ static void apply_dsc_policy_for_stream(struct amdgpu_dm_connector *aconnector,
 	uint32_t link_bandwidth_kbps;
 	uint32_t max_dsc_target_bpp_limit_override = 0;
 	struct dc *dc = sink->ctx->dc;
+	uint32_t max_supported_bw_in_kbps, timing_bw_in_kbps;
+	uint32_t dsc_max_supported_bw_in_kbps;
 
 	link_bandwidth_kbps = dc_link_bandwidth_kbps(aconnector->dc_link,
 							dc_link_get_link_cap(aconnector->dc_link));
@@ -6138,16 +6142,37 @@ static void apply_dsc_policy_for_stream(struct amdgpu_dm_connector *aconnector,
 		apply_dsc_policy_for_edp(aconnector, sink, stream, dsc_caps, max_dsc_target_bpp_limit_override);
 
 	} else if (aconnector->dc_link && sink->sink_signal == SIGNAL_TYPE_DISPLAY_PORT) {
-
-		if (dc_dsc_compute_config(aconnector->dc_link->ctx->dc->res_pool->dscs[0],
+		if (sink->link->dpcd_caps.dongle_type == DISPLAY_DONGLE_NONE) {
+			if (dc_dsc_compute_config(aconnector->dc_link->ctx->dc->res_pool->dscs[0],
 						dsc_caps,
 						aconnector->dc_link->ctx->dc->debug.dsc_min_slice_height_override,
 						max_dsc_target_bpp_limit_override,
 						link_bandwidth_kbps,
 						&stream->timing,
 						&stream->timing.dsc_cfg)) {
-			stream->timing.flags.DSC = 1;
-			DRM_DEBUG_DRIVER("%s: [%s] DSC is selected from SST RX\n", __func__, drm_connector->name);
+				stream->timing.flags.DSC = 1;
+				DRM_DEBUG_DRIVER("%s: [%s] DSC is selected from SST RX\n",
+								 __func__, drm_connector->name);
+			}
+		} else if (sink->link->dpcd_caps.dongle_type == DISPLAY_DONGLE_DP_HDMI_CONVERTER) {
+			timing_bw_in_kbps = dc_bandwidth_in_kbps_from_timing(&stream->timing);
+			max_supported_bw_in_kbps = link_bandwidth_kbps;
+			dsc_max_supported_bw_in_kbps = link_bandwidth_kbps;
+
+			if (timing_bw_in_kbps > max_supported_bw_in_kbps &&
+					max_supported_bw_in_kbps > 0 &&
+					dsc_max_supported_bw_in_kbps > 0)
+				if (dc_dsc_compute_config(aconnector->dc_link->ctx->dc->res_pool->dscs[0],
+						dsc_caps,
+						aconnector->dc_link->ctx->dc->debug.dsc_min_slice_height_override,
+						max_dsc_target_bpp_limit_override,
+						dsc_max_supported_bw_in_kbps,
+						&stream->timing,
+						&stream->timing.dsc_cfg)) {
+					stream->timing.flags.DSC = 1;
+					DRM_DEBUG_DRIVER("%s: [%s] DSC is selected from DP-HDMI PCON\n",
+									 __func__, drm_connector->name);
+				}
 		}
 	}
 
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index e8e70840a622..2c73594da85f 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -585,8 +585,17 @@ bool dm_helpers_dp_write_dsc_enable(
 	}
 
 	if (stream->signal == SIGNAL_TYPE_DISPLAY_PORT || stream->signal == SIGNAL_TYPE_EDP) {
-		ret = dm_helpers_dp_write_dpcd(ctx, stream->link, DP_DSC_ENABLE, &enable_dsc, 1);
-		DC_LOG_DC("Send DSC %s to sst display\n", enable_dsc ? "enable" : "disable");
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+		if (stream->sink->link->dpcd_caps.dongle_type == DISPLAY_DONGLE_NONE) {
+#endif
+			ret = dm_helpers_dp_write_dpcd(ctx, stream->link, DP_DSC_ENABLE, &enable_dsc, 1);
+			DC_LOG_DC("Send DSC %s to SST RX\n", enable_dsc ? "enable" : "disable");
+#if defined(CONFIG_DRM_AMD_DC_DCN)
+		} else if (stream->sink->link->dpcd_caps.dongle_type == DISPLAY_DONGLE_DP_HDMI_CONVERTER) {
+			ret = dm_helpers_dp_write_dpcd(ctx, stream->link, DP_DSC_ENABLE, &enable_dsc, 1);
+			DC_LOG_DC("Send DSC %s to DP-HDMI PCON\n", enable_dsc ? "enable" : "disable");
+		}
+#endif
 	}
 
 	return (ret > 0);
-- 
2.25.1