[PATCH 09/19] drm/amd/display: Unconditionally clear training pattern set after lt

[Aurabindo Pillai]

From: Wesley Chalmers <wesley.chalm...@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.chalm...@amd.com>
Reviewed-by: Jun Lei <jun....@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pil...@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,
                                &lt_settings,
-- 
2.31.1

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