Commit 80789bcf authored by Jimmy Kizito's avatar Jimmy Kizito Committed by Alex Deucher
Browse files

drm/amd/display: Implement end of training for hop in DPIA display path 



[Why & How]
Clear training pattern sequence for hop in display path once clock
recovery and equalization phases of DP tunnel link training completed.

Reviewed-by: default avatarJun Lei <Jun.Lei@amd.com>
Acked-by: default avatarWayne Lin <Wayne.Lin@amd.com>
Acked-by: default avatarNicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Acked-by: default avatarHarry Wentland <harry.wentland@amd.com>
Signed-off-by: default avatarJimmy Kizito <Jimmy.Kizito@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 847a9038

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

+9 −2
Original line number Diff line number Diff line
@@ -2389,14 +2389,21 @@ bool perform_link_training_with_retries( 
			dc_link_dp_perform_link_training_skip_aux(link, &current_setting);

			return true;

		} else {

			if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA)

			/** @todo Consolidate USB4 DP and DPx.x training. */

			if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA) {

				status = dc_link_dpia_perform_link_training(link,

									    &current_setting,

									    skip_video_pattern);

			else



				/* Transmit idle pattern once training successful. */

				if (status == LINK_TRAINING_SUCCESS)

					dp_set_hw_test_pattern(link, DP_TEST_PATTERN_VIDEO_MODE,

							       NULL, 0);

			} 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/core/dc_link_dpia.c

+74 −3
Original line number Diff line number Diff line
@@ -737,13 +737,84 @@ static enum link_training_result dpia_training_eq_phase(struct dc_link *link, 
}



/* End training of specified hop in display path. */

static enum dc_status dpcd_clear_lt_pattern(struct dc_link *link, uint32_t hop)

{

	union dpcd_training_pattern dpcd_pattern = { {0} };

	uint32_t dpcd_tps_offset = DP_TRAINING_PATTERN_SET;

	enum dc_status status;



	if (hop != DPRX)

		dpcd_tps_offset = DP_TRAINING_PATTERN_SET_PHY_REPEATER1 +

			((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * (hop - 1));



	status = core_link_write_dpcd(link,

			DP_TRAINING_PATTERN_SET,

			&dpcd_pattern.raw,

			sizeof(dpcd_pattern.raw));



	return status;

}



/* End training of specified hop in display path.

 *

 * In transparent LTTPR mode:

 * - driver clears training pattern for the specified hop in DPCD.

 * In non-transparent LTTPR mode:

 * - in addition to clearing training pattern, driver issues USB4 tunneling

 * (SET_CONFIG) messages to notify DPOA when training is done for first hop

 * (DPTX-to-DPIA) and last hop (DPRX).

 *

 * @param link DPIA link being trained.

 * @param hop The Hop in display path. DPRX = 0.

 */

static enum link_training_result dpia_training_end(struct dc_link *link,

		uint32_t hop)

{

	enum link_training_result result;

	enum link_training_result result = LINK_TRAINING_SUCCESS;

	uint8_t repeater_cnt = 0; /* Number of hops/repeaters in display path. */

	enum dc_status status;



	if (link->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) {

		repeater_cnt = dp_convert_to_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt);



	/** @todo Fail until implemented. */

		if (hop == repeater_cnt) { /* DPTX-to-DPIA */

			/* Send SET_CONFIG(SET_TRAINING:0xff) to notify DPOA that

			 * DPTX-to-DPIA hop trained. No DPCD write needed for first hop.

			 */

			status = core_link_send_set_config(link,

					DPIA_SET_CFG_SET_TRAINING,

					DPIA_TS_UFP_DONE);

			if (status != DC_OK)

				result = LINK_TRAINING_ABORT;

		} else { /* DPOA-to-x */

			/* Write 0x0 to TRAINING_PATTERN_SET */

			status = dpcd_clear_lt_pattern(link, hop);

			if (status != DC_OK)

				result = LINK_TRAINING_ABORT;

		}



		/* Notify DPOA that non-transparent link training of DPRX done. */

		if (hop == DPRX && result != LINK_TRAINING_ABORT) {

			status = core_link_send_set_config(link,

					DPIA_SET_CFG_SET_TRAINING,

					DPIA_TS_DPRX_DONE);

			if (status != DC_OK)

				result = LINK_TRAINING_ABORT;

		}



	} else { /* non-LTTPR or transparent LTTPR. */

		/* Write 0x0 to TRAINING_PATTERN_SET */

		status = dpcd_clear_lt_pattern(link, hop);

		if (status != DC_OK)

			result = LINK_TRAINING_ABORT;

	}



	DC_LOG_HW_LINK_TRAINING("%s\n DPIA(%d) end\n - hop(%d)\n - result(%d)\n - LTTPR mode(%d)\n",

				__func__,

				link->link_id.enum_id - ENUM_ID_1,

				hop,

				result,

				link->lttpr_mode);



	return result;

}