On 8/8/2023 3:19 PM, Kuogee Hsieh wrote:
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.
There should be a line break here.
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@xxxxxxxxxxx>
I tested and confirm that without this patch, I see this spam atleast
once per reboot but after this patch, I have not seen this for 5
consecutive reboots.
Hence,
Tested-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx> # sc7280
Looking at the code flow, the dp_ctrl_reinitialize_mainlink() certainly
looks redundant where it is, considering that the clks were enabled just
a couple of lines above in dp_ctrl_enable_mainlink_clocks().
Hence with the minor fix in the commit,
Reviewed-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
---
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 a7a5c7e..77a8d93 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -1774,13 +1774,6 @@ 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) {
@@ -1832,6 +1825,12 @@ 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)
