Commit 97d1765e authored by Wesley Chalmers's avatar Wesley Chalmers Committed by Alex Deucher
Browse files

drm/amd/display: Unconditionally clear training pattern set after lt 



[WHY]
While Link Training is being performed,
and the LTTPRs are in Non-LTTPR or LTTPR Transparent mode,
any DPCD registers besides those used for Link Training are not to be
accessed.

The spec defines the link training registers as DP_TRAINING_PATTERN_SET
(102h) to DP_TRAINING_LANE3_SET (106h), and DP_LANE0_1_STATUS (202h)
to DP_ADJUST_REQUEST_LANE2_3 (207h).

[HOW]
Move the current write to DPCD Address DP_LINK_TRAINING_PATTERN_SET out
of its conditional block.

Signed-off-by: default avatarWesley Chalmers <Wesley.Chalmers@amd.com>
Reviewed-by: default avatarJun Lei <Jun.Lei@amd.com>
Acked-by: default avatarAurabindo Pillai <aurabindo.pillai@amd.com>
Tested-by: default avatarDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 41ef8fbb

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

+4 −5
Original line number Diff line number Diff line
@@ -1132,11 +1132,6 @@ static inline enum link_training_result perform_link_training_int( 
	enum link_training_result status)

{

	union lane_count_set lane_count_set = { {0} };

	union dpcd_training_pattern dpcd_pattern = { {0} };



	/* 3. set training not in progress*/

	dpcd_pattern.v1_4.TRAINING_PATTERN_SET = DPCD_TRAINING_PATTERN_VIDEOIDLE;

	dpcd_set_training_pattern(link, dpcd_pattern);



	/* 4. mainlink output idle pattern*/

	dp_set_hw_test_pattern(link, DP_TEST_PATTERN_VIDEO_MODE, NULL, 0);
@@ -1560,6 +1555,7 @@ enum link_training_result dc_link_dp_perform_link_training( 
{

	enum link_training_result status = LINK_TRAINING_SUCCESS;

	struct link_training_settings lt_settings;

	union dpcd_training_pattern dpcd_pattern = { { 0 } };



	bool fec_enable;

	uint8_t repeater_cnt;
@@ -1624,6 +1620,9 @@ enum link_training_result dc_link_dp_perform_link_training( 
		}

	}



	/* 3. set training not in progress*/

	dpcd_pattern.v1_4.TRAINING_PATTERN_SET = DPCD_TRAINING_PATTERN_VIDEOIDLE;

	dpcd_set_training_pattern(link, dpcd_pattern);

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

		status = perform_link_training_int(link,

				&lt_settings,