[PATCH 09/19] drm/amd/display: Unconditionally clear training pattern set after lt
Aurabindo Pillai
aurabindo.pillai at amd.com
Fri Apr 16 14:34:07 UTC 2021
From: Wesley Chalmers <Wesley.Chalmers at amd.com>
[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 at amd.com>
Reviewed-by: Jun Lei <Jun.Lei at amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai at amd.com>
---
drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
index e6f8f3c255bc..bbf2865b25c5 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
@@ -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,
<_settings,
--
2.31.1
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