drm/dp_mst: Parse FEC capability on MST ports (a3c2b0ff) · Commits · 戴 / test

As of DP1.4, ENUM_PATH_RESOURCES returns a bit indicating if FEC can be supported up to that point in the MST network. The bit is the first byte of the ENUM_PATH_RESOURCES ack reply, bottom-most bit (refer to section 2.11.9.4 of DP standard, v1.4) That value is needed for FEC and DSC support Store it on drm_dp_mst_port Reviewed-by:

Lyude Paul <lyude@redhat.com> Reviewed-by:

Harry Wentland <harry.wentland@amd.com> Signed-off-by:

David Francis <David.Francis@amd.com> Signed-off-by:

Mikita Lipski <mikita.lipski@amd.com> Signed-off-by:

Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/drm_dp_mst_topology.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -853,6 +853,7 @@ static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband
		{
		int idx = 1;
		repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf;
		repmsg->u.path_resources.fec_capable = raw->msg[idx] & 0x1;
		idx++;
		if (idx > raw->curlen)
		goto fail_len;
		@@ -2951,6 +2952,7 @@ drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
		path_res->avail_payload_bw_number);
		port->available_pbn =
		path_res->avail_payload_bw_number;
		port->fec_capable = path_res->fec_capable;
		}
		}

include/drm/drm_dp_mst_helper.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -156,6 +156,8 @@ struct drm_dp_mst_port {
		* audio-capable.
		*/
		bool has_audio;

		bool fec_capable;
		};

		/**
		@@ -383,6 +385,7 @@ struct drm_dp_port_number_req {

		struct drm_dp_enum_path_resources_ack_reply {
		u8 port_number;
		bool fec_capable;
		u16 full_payload_bw_number;
		u16 avail_payload_bw_number;
		};

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