Commit cd6a9a1c authored by Wenjing Liu's avatar Wenjing Liu Committed by Alex Deucher
Browse files

drm/amd/display: isolate 8b 10b link training sequence into its own function 



[how]
1. move 8b 10 link trianing into its own function
2. make link status check after a link success link as part of
dp transition to video idle sequence.

Signed-off-by: default avatarWenjing Liu <wenjing.liu@amd.com>
Reviewed-by: default avatarJun Lei <Jun.Lei@amd.com>
Acked-by: default avatarQingqing Zhuo <qingqing.zhuo@amd.com>
Tested-by: default avatarDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 3df21257

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

+62 −56
Original line number Diff line number Diff line
@@ -1170,8 +1170,16 @@ static inline enum link_training_result dp_transition_to_video_idle( 
	 * TPS4 must be used instead of POST_LT_ADJ_REQ.

	 */

	if (link->dpcd_caps.max_ln_count.bits.POST_LT_ADJ_REQ_SUPPORTED != 1 ||

			lt_settings->pattern_for_eq == DP_TRAINING_PATTERN_SEQUENCE_4)

			lt_settings->pattern_for_eq == DP_TRAINING_PATTERN_SEQUENCE_4) {

		/* delay 5ms after Main Link output idle pattern and then check

		 * DPCD 0202h.

		 */

		if (link->connector_signal != SIGNAL_TYPE_EDP && status == LINK_TRAINING_SUCCESS) {

			msleep(5);

			status = dp_check_link_loss_status(link, lt_settings);

		}

		return status;

	}



	if (status == LINK_TRAINING_SUCCESS &&

		perform_post_lt_adj_req_sequence(link, lt_settings) == false)
@@ -1621,18 +1629,9 @@ enum dc_status dpcd_configure_lttpr_mode(struct dc_link *link, struct link_train 


static void dpcd_exit_training_mode(struct dc_link *link)

{

	const uint8_t clear_pattern = 0;



	/* clear training pattern set */

	core_link_write_dpcd(

			link,

			DP_TRAINING_PATTERN_SET,

			&clear_pattern,

			sizeof(clear_pattern));

	DC_LOG_HW_LINK_TRAINING("%s\n %x pattern = %x\n",

			__func__,

			DP_TRAINING_PATTERN_SET,

			clear_pattern);

	dpcd_set_training_pattern(link, DP_TRAINING_PATTERN_VIDEOIDLE);

}



enum dc_status dpcd_configure_channel_coding(struct dc_link *link,
@@ -1656,41 +1655,22 @@ enum dc_status dpcd_configure_channel_coding(struct dc_link *link, 
	return status;

}



enum link_training_result dc_link_dp_perform_link_training(

static enum link_training_result dp_perform_8b_10b_link_training(

		struct dc_link *link,

	const struct dc_link_settings *link_settings,

	bool skip_video_pattern)

		struct link_training_settings *lt_settings)

{

	enum link_training_result status = LINK_TRAINING_SUCCESS;

	struct link_training_settings lt_settings;



	/* reset previous training states */

	dpcd_exit_training_mode(link);



	/* decide training settings */

	dp_decide_training_settings(

			link,

			link_settings,

			&link->preferred_training_settings,

			&lt_settings);

	dpcd_configure_lttpr_mode(link, &lt_settings);

	dp_set_fec_ready(link, lt_settings.should_set_fec_ready);

	dpcd_configure_channel_coding(link, &lt_settings);



	/* enter training mode:

	 * Per DP specs starting from here, DPTX device shall not issue

	 * Non-LT AUX transactions inside training mode.

	 */

	uint8_t repeater_cnt;

	uint8_t repeater_id;



	if (link->ctx->dc->work_arounds.lt_early_cr_pattern)

		start_clock_recovery_pattern_early(link, &lt_settings, DPRX);

		start_clock_recovery_pattern_early(link, lt_settings, DPRX);



	/* 1. set link rate, lane count and spread. */

	dpcd_set_link_settings(link, &lt_settings);

	dpcd_set_link_settings(link, lt_settings);



	if (link->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) {

		uint8_t repeater_cnt;

		uint8_t repeater_id;



		/* 2. perform link training (set link training done

		 *  to false is done as well)
@@ -1699,13 +1679,13 @@ enum link_training_result dc_link_dp_perform_link_training( 


		for (repeater_id = repeater_cnt; (repeater_id > 0 && status == LINK_TRAINING_SUCCESS);

				repeater_id--) {

			status = perform_clock_recovery_sequence(link, &lt_settings, repeater_id);

			status = perform_clock_recovery_sequence(link, lt_settings, repeater_id);



			if (status != LINK_TRAINING_SUCCESS)

				break;



			status = perform_channel_equalization_sequence(link,

					&lt_settings,

					lt_settings,

					repeater_id);



			if (status != LINK_TRAINING_SUCCESS)
@@ -1716,36 +1696,62 @@ enum link_training_result dc_link_dp_perform_link_training( 
	}



	if (status == LINK_TRAINING_SUCCESS) {

		status = perform_clock_recovery_sequence(link, &lt_settings, DPRX);

		status = perform_clock_recovery_sequence(link, lt_settings, DPRX);

	if (status == LINK_TRAINING_SUCCESS) {

		status = perform_channel_equalization_sequence(link,

					&lt_settings,

					lt_settings,

					DPRX);

		}

	}



	/* 3. set training not in progress*/

	dpcd_set_training_pattern(link, DP_TRAINING_PATTERN_VIDEOIDLE);

	if ((status == LINK_TRAINING_SUCCESS) || !skip_video_pattern) {

		status = dp_transition_to_video_idle(link,

				&lt_settings,

				status);

	return status;

}



	/* delay 5ms after Main Link output idle pattern and then check

	 * DPCD 0202h.

enum link_training_result dc_link_dp_perform_link_training(

	struct dc_link *link,

	const struct dc_link_settings *link_settings,

	bool skip_video_pattern)

{

	enum link_training_result status = LINK_TRAINING_SUCCESS;

	struct link_training_settings lt_settings;

	enum dp_link_encoding encoding =

			dp_get_link_encoding_format(link_settings);



	/* decide training settings */

	dp_decide_training_settings(

			link,

			link_settings,

			&link->preferred_training_settings,

			&lt_settings);



	/* reset previous training states */

	dpcd_exit_training_mode(link);



	/* configure link prior to entering training mode */

	dpcd_configure_lttpr_mode(link, &lt_settings);

	dp_set_fec_ready(link, lt_settings.should_set_fec_ready);

	dpcd_configure_channel_coding(link, &lt_settings);



	/* enter training mode:

	 * Per DP specs starting from here, DPTX device shall not issue

	 * Non-LT AUX transactions inside training mode.

	 */

	if (link->connector_signal != SIGNAL_TYPE_EDP && status == LINK_TRAINING_SUCCESS) {

		msleep(5);

		status = dp_check_link_loss_status(link, &lt_settings);

	}

	if (encoding == DP_8b_10b_ENCODING)

		status = dp_perform_8b_10b_link_training(link, &lt_settings);

	else

		ASSERT(0);



	/* 6. print status message*/

	print_status_message(link, &lt_settings, status);

	/* exit training mode and switch to video idle */

	dpcd_exit_training_mode(link);

	if ((status == LINK_TRAINING_SUCCESS) || !skip_video_pattern)

		status = dp_transition_to_video_idle(link,

				&lt_settings,

				status);



	/* dump debug data */

	print_status_message(link, &lt_settings, status);

	if (status != LINK_TRAINING_SUCCESS)

		link->ctx->dc->debug_data.ltFailCount++;



	return status;

}