drm/amd/display: Stub out DPIA link training call

[why & how]
Add stub for DPIA link training and define new DPIA DMUB commands
to support it.
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Wayne Lin <Wayne.Lin@amd.com>
Acked-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Jimmy Kizito <Jimmy.Kizito@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c

@@ -2310,6 +2310,23 @@ enum link_training_result dc_link_dp_perform_link_training(
 	return status;
 }
 
+/*
+ * Train DP tunneling link for USB4 DPIA display endpoint.
+ *
+ * DPIA equivalent of dc_link_dp_perfrorm_link_training.
+ */
+enum link_training_result dc_link_dpia_perform_link_training(struct dc_link *link,
+	const struct dc_link_settings *link_setting,
+	bool skip_video_pattern)
+{
+	enum link_training_result status;
+
+	/** @todo Always fail until USB4 DPIA training implemented. */
+	status = LINK_TRAINING_CR_FAIL_LANE0;
+
+	return status;
+}
+
 bool perform_link_training_with_retries(
 	const struct dc_link_settings *link_setting,
 	bool skip_video_pattern,
@@ -2381,10 +2398,15 @@ bool perform_link_training_with_retries(
 			dc_link_dp_perform_link_training_skip_aux(link, &current_setting);
 			return true;
 		} else {
-				status = dc_link_dp_perform_link_training(
-										link,
+			if (link->is_dig_mapping_flexible)
+				status = dc_link_dpia_perform_link_training(link,
+									    link_setting,
+									    skip_video_pattern);
+			else
+				status = dc_link_dp_perform_link_training(link,
 									  &current_setting,
 									  skip_video_pattern);
+
 			if (status == LINK_TRAINING_SUCCESS)
 				return true;
 		}

drivers/gpu/drm/amd/display/dc/dcn31/dcn31_dio_link_encoder.c

@@ -366,11 +366,44 @@ void dcn31_link_encoder_construct_minimal(
 		SIGNAL_TYPE_EDP;
 }
 
+/* DPIA equivalent of link_transmitter_control. */
+static bool link_dpia_control(struct dc_context *dc_ctx,
+	struct dmub_cmd_dig_dpia_control_data *dpia_control)
+{
+	union dmub_rb_cmd cmd;
+	struct dc_dmub_srv *dmub = dc_ctx->dmub_srv;
+
+	memset(&cmd, 0, sizeof(cmd));
+
+	cmd.dig1_dpia_control.header.type = DMUB_CMD__DPIA;
+	cmd.dig1_dpia_control.header.sub_type =
+			DMUB_CMD__DPIA_DIG1_DPIA_CONTROL;
+	cmd.dig1_dpia_control.header.payload_bytes =
+		sizeof(cmd.dig1_dpia_control) -
+		sizeof(cmd.dig1_dpia_control.header);
+
+	cmd.dig1_dpia_control.dpia_control = *dpia_control;
+
+	dc_dmub_srv_cmd_queue(dmub, &cmd);
+	dc_dmub_srv_cmd_execute(dmub);
+	dc_dmub_srv_wait_idle(dmub);
+
+	return false;
+}
+
+static void link_encoder_disable(struct dcn10_link_encoder *enc10)
+{
+	/* reset training complete */
+	REG_UPDATE(DP_LINK_CNTL, DP_LINK_TRAINING_COMPLETE, 0);
+}
+
 void dcn31_link_encoder_enable_dp_output(
 	struct link_encoder *enc,
 	const struct dc_link_settings *link_settings,
 	enum clock_source_id clock_source)
 {
+	struct dcn10_link_encoder *enc10 = TO_DCN10_LINK_ENC(enc);
+
 	/* Enable transmitter and encoder. */
 	if (!link_enc_cfg_is_transmitter_mappable(enc->ctx->dc, enc)) {
 
@@ -378,7 +411,30 @@ void dcn31_link_encoder_enable_dp_output(
 
 	} else {
 
-		/** @todo Handle transmitter with programmable mapping to link encoder. */
+		struct dmub_cmd_dig_dpia_control_data dpia_control = { 0 };
+		struct dc_link *link;
+
+		link = link_enc_cfg_get_link_using_link_enc(enc->ctx->dc, enc->preferred_engine);
+
+		enc1_configure_encoder(enc10, link_settings);
+
+		dpia_control.action = (uint8_t)TRANSMITTER_CONTROL_ENABLE;
+		dpia_control.enc_id = enc->preferred_engine;
+		dpia_control.mode_laneset.digmode = 0; /* 0 for SST; 5 for MST */
+		dpia_control.lanenum = (uint8_t)link_settings->lane_count;
+		dpia_control.symclk_10khz = link_settings->link_rate *
+				LINK_RATE_REF_FREQ_IN_KHZ / 10;
+		dpia_control.hpdsel = 5; /* Unused by DPIA */
+
+		if (link) {
+			dpia_control.dpia_id = link->ddc_hw_inst;
+		} else {
+			DC_LOG_ERROR("%s: Failed to execute DPIA enable DMUB command.\n", __func__);
+			BREAK_TO_DEBUGGER();
+			return;
+		}
+
+		link_dpia_control(enc->ctx, &dpia_control);
 	}
 }
 
@@ -387,6 +443,8 @@ void dcn31_link_encoder_enable_dp_mst_output(
 	const struct dc_link_settings *link_settings,
 	enum clock_source_id clock_source)
 {
+	struct dcn10_link_encoder *enc10 = TO_DCN10_LINK_ENC(enc);
+
 	/* Enable transmitter and encoder. */
 	if (!link_enc_cfg_is_transmitter_mappable(enc->ctx->dc, enc)) {
 
@@ -394,7 +452,30 @@ void dcn31_link_encoder_enable_dp_mst_output(
 
 	} else {
 
-		/** @todo Handle transmitter with programmable mapping to link encoder. */
+		struct dmub_cmd_dig_dpia_control_data dpia_control = { 0 };
+		struct dc_link *link;
+
+		link = link_enc_cfg_get_link_using_link_enc(enc->ctx->dc, enc->preferred_engine);
+
+		enc1_configure_encoder(enc10, link_settings);
+
+		dpia_control.action = (uint8_t)TRANSMITTER_CONTROL_ENABLE;
+		dpia_control.enc_id = enc->preferred_engine;
+		dpia_control.mode_laneset.digmode = 5; /* 0 for SST; 5 for MST */
+		dpia_control.lanenum = (uint8_t)link_settings->lane_count;
+		dpia_control.symclk_10khz = link_settings->link_rate *
+				LINK_RATE_REF_FREQ_IN_KHZ / 10;
+		dpia_control.hpdsel = 5; /* Unused by DPIA */
+
+		if (link) {
+			dpia_control.dpia_id = link->ddc_hw_inst;
+		} else {
+			DC_LOG_ERROR("%s: Failed to execute DPIA enable DMUB command.\n", __func__);
+			BREAK_TO_DEBUGGER();
+			return;
+		}
+
+		link_dpia_control(enc->ctx, &dpia_control);
 	}
 }
 
@@ -402,6 +483,8 @@ void dcn31_link_encoder_disable_output(
 	struct link_encoder *enc,
 	enum signal_type signal)
 {
+	struct dcn10_link_encoder *enc10 = TO_DCN10_LINK_ENC(enc);
+
 	/* Disable transmitter and encoder. */
 	if (!link_enc_cfg_is_transmitter_mappable(enc->ctx->dc, enc)) {
 
@@ -409,7 +492,36 @@ void dcn31_link_encoder_disable_output(
 
 	} else {
 
-		/** @todo Handle transmitter with programmable mapping to link encoder. */
+		struct dmub_cmd_dig_dpia_control_data dpia_control = { 0 };
+		struct dc_link *link;
+
+		if (!dcn10_is_dig_enabled(enc))
+			return;
+
+		link = link_enc_cfg_get_link_using_link_enc(enc->ctx->dc, enc->preferred_engine);
+
+		dpia_control.action = (uint8_t)TRANSMITTER_CONTROL_DISABLE;
+		dpia_control.enc_id = enc->preferred_engine;
+		if (signal == SIGNAL_TYPE_DISPLAY_PORT) {
+			dpia_control.mode_laneset.digmode = 0; /* 0 for SST; 5 for MST */
+		} else if (signal == SIGNAL_TYPE_DISPLAY_PORT_MST) {
+			dpia_control.mode_laneset.digmode = 5; /* 0 for SST; 5 for MST */
+		} else {
+			DC_LOG_ERROR("%s: USB4 DPIA only supports DisplayPort.\n", __func__);
+			BREAK_TO_DEBUGGER();
+		}
+
+		if (link) {
+			dpia_control.dpia_id = link->ddc_hw_inst;
+		} else {
+			DC_LOG_ERROR("%s: Failed to execute DPIA enable DMUB command.\n", __func__);
+			BREAK_TO_DEBUGGER();
+			return;
+		}
+
+		link_dpia_control(enc->ctx, &dpia_control);
+
+		link_encoder_disable(enc10);
 	}
 }
 

drivers/gpu/drm/amd/display/dmub/inc/dmub_cmd.h

@@ -653,6 +653,10 @@ enum dmub_cmd_type {
 	 * Command type used for all panel control commands.
 	 */
 	DMUB_CMD__PANEL_CNTL = 74,
+	/**
+	 * Command type used for interfacing with DPIA.
+	 */
+	DMUB_CMD__DPIA = 77,
 	/**
 	 * Command type used for EDID CEA parsing
 	 */
@@ -681,6 +685,11 @@ enum dmub_out_cmd_type {
 	DMUB_OUT_CMD__DP_HPD_NOTIFY = 2,
 };
 
+/* DMUB_CMD__DPIA command sub-types. */
+enum dmub_cmd_dpia_type {
+	DMUB_CMD__DPIA_DIG1_DPIA_CONTROL = 0,
+};
+
 #pragma pack(push, 1)
 
 /**
@@ -1000,6 +1009,34 @@ struct dmub_rb_cmd_dig1_transmitter_control {
 	union dmub_cmd_dig1_transmitter_control_data transmitter_control; /**< payload */
 };
 
+/**
+ * DPIA tunnel command parameters.
+ */
+struct dmub_cmd_dig_dpia_control_data {
+	uint8_t enc_id;         /** 0 = ENGINE_ID_DIGA, ... */
+	uint8_t action;         /** ATOM_TRANSMITER_ACTION_DISABLE/ENABLE/SETUP_VSEMPH */
+	union {
+		uint8_t digmode;    /** enum atom_encode_mode_def */
+		uint8_t dplaneset;  /** DP voltage swing and pre-emphasis value */
+	} mode_laneset;
+	uint8_t lanenum;        /** Lane number 1, 2, 4, 8 */
+	uint32_t symclk_10khz;  /** Symbol Clock in 10Khz */
+	uint8_t hpdsel;         /** =0: HPD is not assigned */
+	uint8_t digfe_sel;      /** DIG stream( front-end ) selection, bit0 - DIG0 FE */
+	uint8_t dpia_id;        /** Index of DPIA */
+	uint8_t fec_rdy : 1;
+	uint8_t reserved : 7;
+	uint32_t reserved1;
+};
+
+/**
+ * DMUB command for DPIA tunnel control.
+ */
+struct dmub_rb_cmd_dig1_dpia_control {
+	struct dmub_cmd_header header;
+	struct dmub_cmd_dig_dpia_control_data dpia_control;
+};
+
 /**
  * struct dmub_rb_cmd_dpphy_init - DPPHY init.
  */
@@ -2441,6 +2478,10 @@ union dmub_rb_cmd {
 	 * Definition of a DMUB_CMD__VBIOS_LVTMA_CONTROL command.
 	 */
 	struct dmub_rb_cmd_lvtma_control lvtma_control;
+	/**
+	 * Definition of a DMUB_CMD__DPIA_DIG1_CONTROL command.
+	 */
+	struct dmub_rb_cmd_dig1_dpia_control dig1_dpia_control;
 	/**
 	 * Definition of a DMUB_CMD__EDID_CEA command.
 	 */