[PATCH 14/24] drm/amd/display: remove PHY repeater count check for LTTPR mode

Rodrigo Siqueira Rodrigo.Siqueira at amd.com
Sun Jan 23 18:20:11 UTC 2022


From: Sung Joon Kim <sungkim at amd.com>

[why]
Due to bad hardware, the PHY repeater count in LTTPR cap is read as 0xFF
in some monitors while the LTTPR is actually present.

[how]
Remove PHY repeater counter check when configuring LTTPR mode.

Reviewed-by: Jun Lei <Jun.Lei at amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira at amd.com>
Signed-off-by: Sung Joon Kim <sungkim at amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 3 +--
 1 file changed, 1 insertion(+), 2 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 0033d2a0cfe5..f7ddba9cc63a 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
@@ -5069,9 +5069,8 @@ bool dp_retrieve_lttpr_cap(struct dc_link *link)
 								DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV];
 
 		/* Attempt to train in LTTPR transparent mode if repeater count exceeds 8. */
-		is_lttpr_present = (dp_convert_to_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt) != 0 &&
+		is_lttpr_present = (link->dpcd_caps.lttpr_caps.max_lane_count > 0 &&
 				link->dpcd_caps.lttpr_caps.phy_repeater_cnt < 0xff &&
-				link->dpcd_caps.lttpr_caps.max_lane_count > 0 &&
 				link->dpcd_caps.lttpr_caps.max_lane_count <= 4 &&
 				link->dpcd_caps.lttpr_caps.revision.raw >= 0x14);
 		if (is_lttpr_present) {
-- 
2.25.1



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