drm/i915: Try harder to complete DP training pattern 1
In commit cdb0e95bf571dccc1f75fef9bdad21b167ef0b37
Author: Keith Packard <keithp@keithp.com>
Date: Tue Nov 1 20:00:06 2011 -0700
drm/i915: Try harder during dp pattern 1 link training
extra passes were made to retry the same voltage and then retry a full
clock reset. However, as coverity pointed out, we never tried the full
clock reset as we broke out of the loop early.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index c63f54e..c14d407 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1798,8 +1798,7 @@
if ((intel_dp->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0)
break;
if (i == intel_dp->lane_count && voltage_tries == 5) {
- ++loop_tries;
- if (loop_tries == 5) {
+ if (++loop_tries == 5) {
DRM_DEBUG_KMS("too many full retries, give up\n");
break;
}
@@ -1809,15 +1808,11 @@
}
/* Check to see if we've tried the same voltage 5 times */
- if ((intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) == voltage) {
- ++voltage_tries;
- if (voltage_tries == 5) {
- DRM_DEBUG_KMS("too many voltage retries, give up\n");
- break;
- }
- } else
+ if ((intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) != voltage) {
+ voltage = intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
voltage_tries = 0;
- voltage = intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
+ } else
+ ++voltage_tries;
/* Compute new intel_dp->train_set as requested by target */
intel_get_adjust_train(intel_dp, link_status);