5.15-stable review patch. If anyone has any objections, please let me know.
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From: Kuogee Hsieh quic_khsieh@quicinc.com
[ Upstream commit 0c1a2e69bcb506f48ebf94bd199bab0b93f66da2 ]
DP PHY re-initialization done using dp_ctrl_reinitialize_mainlink() will cause PLL unlocked initially and then PLL gets locked at the end of initialization. PLL_UNLOCKED interrupt will fire during this time if the interrupt mask is enabled.
However currently DP driver link training implementation incorrectly re-initializes PHY unconditionally during link training as the PHY was already configured in dp_ctrl_enable_mainlink_clocks().
Fix this by re-initializing the PHY only if the previous link training failed.
[drm:dp_aux_isr] *ERROR* Unexpected DP AUX IRQ 0x01000000 when not busy
Fixes: c943b4948b58 ("drm/msm/dp: add displayPort driver support") Closes: https://gitlab.freedesktop.org/drm/msm/-/issues/30 Signed-off-by: Kuogee Hsieh quic_khsieh@quicinc.com Tested-by: Abhinav Kumar quic_abhinavk@quicinc.com # sc7280 Reviewed-by: Abhinav Kumar quic_abhinavk@quicinc.com Reviewed-by: Stephen Boyd swboyd@chromium.org Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Tested-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Patchwork: https://patchwork.freedesktop.org/patch/551847/ Link: https://lore.kernel.org/r/1691533190-19335-1-git-send-email-quic_khsieh@quic... [quic_abhinavk@quicinc.com: added line break in commit text] Signed-off-by: Abhinav Kumar quic_abhinavk@quicinc.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/msm/dp/dp_ctrl.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c index 6d9eec98e0d38..854173df67018 100644 --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c @@ -1682,13 +1682,6 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl) return rc;
while (--link_train_max_retries) { - rc = dp_ctrl_reinitialize_mainlink(ctrl); - if (rc) { - DRM_ERROR("Failed to reinitialize mainlink. rc=%d\n", - rc); - break; - } - training_step = DP_TRAINING_NONE; rc = dp_ctrl_setup_main_link(ctrl, &training_step); if (rc == 0) { @@ -1740,6 +1733,12 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl) /* stop link training before start re training */ dp_ctrl_clear_training_pattern(ctrl); } + + rc = dp_ctrl_reinitialize_mainlink(ctrl); + if (rc) { + DRM_ERROR("Failed to reinitialize mainlink. rc=%d\n", rc); + break; + } }
if (ctrl->link->sink_request & DP_TEST_LINK_PHY_TEST_PATTERN)