Setting the link bandwidth may change the PLL parameters, which will cause
the PLL to go out of lock, so make sure to apply the MACRO_RST, which
according to the comment is required to be pulsed after the PLL is locked.
Signed-off-by: Lucas Stach <l.st...@pengutronix.de>
---
.../gpu/drm/bridge/analogix/analogix_dp_core.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index b4a47311cfe8..736b2ed745e1 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -243,6 +243,11 @@ static int analogix_dp_link_start(struct
analogix_dp_device *dp)
/* Set link rate and count as you want to establish*/
analogix_dp_set_link_bandwidth(dp, dp->link_train.link_rate);
+ /*
+ * MACRO_RST must be applied after the PLL_LOCK to avoid
+ * the DP inter pair skew issue for at least 10 us
+ */
+ analogix_dp_reset_macro(dp);
analogix_dp_set_lane_count(dp, dp->link_train.lane_count);
/* Setup RX configuration */
@@ -565,12 +570,6 @@ static int analogix_dp_full_link_train(struct
analogix_dp_device *dp,
int retval = 0;
bool training_finished = false;
- /*
- * MACRO_RST must be applied after the PLL_LOCK to avoid
- * the DP inter pair skew issue for at least 10 us
- */
- analogix_dp_reset_macro(dp);
-
/* Initialize by reading RX's DPCD */
analogix_dp_get_max_rx_bandwidth(dp, &dp->link_train.link_rate);
analogix_dp_get_max_rx_lane_count(dp, &dp->link_train.lane_count);
@@ -637,9 +636,12 @@ static int analogix_dp_fast_link_train(struct
analogix_dp_device *dp)
u8 link_align, link_status[2];
enum pll_status status;
- analogix_dp_reset_macro(dp);
-
analogix_dp_set_link_bandwidth(dp, dp->link_train.link_rate);
+ /*
+ * MACRO_RST must be applied after the PLL_LOCK to avoid
+ * the DP inter pair skew issue for at least 10 us
+ */
+ analogix_dp_reset_macro(dp);
analogix_dp_set_lane_count(dp, dp->link_train.lane_count);
analogix_dp_set_lane_link_training(dp);
--
2.39.2
