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

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[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: Wesley Chalmers <Wesley.Chalmers@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Wesley Chalmers 2021-04-05 19:35:37 -04:00 committed by Alex Deucher
parent 41ef8fbbef
commit 97d1765e67
1 changed files with 4 additions and 5 deletions
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9
drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
View file

@ -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,