@@ -1676,6 +1676,11 @@ found:
void intel_dp_set_link_params(struct intel_dp *intel_dp,
const struct intel_crtc_state *pipe_config)
{
+ if (intel_dp->link_rate != pipe_config->port_clock ||
+ intel_dp->lane_count != pipe_config->lane_count) {
+ intel_dp->train_set_valid = false;
+ }
+
intel_dp->link_rate = pipe_config->port_clock;
intel_dp->lane_count = pipe_config->lane_count;
}
@@ -85,6 +85,9 @@ static bool
intel_dp_reset_link_train(struct intel_dp *intel_dp,
uint8_t dp_train_pat)
{
+ DRM_DEBUG_KMS("link training optimization: %s\n",
+ yesno(intel_dp->train_set_valid));
+
if (!intel_dp->train_set_valid)
memset(intel_dp->train_set, 0, sizeof(intel_dp->train_set));
intel_dp_set_signal_levels(intel_dp);
Disable DP link training optimization if DP link configuration changes. If one of the DP link parameters i.e. link rate or lane count changes the link training does no longer apply the previously computed drive current and pre-emphasis level. Instead, the link training is started with zero values. v6: Debug message update to use yesno() routine (Ville) v5: Commit message update. Split the original patch in two. This part considers only changes on link configuration. Removed unnecessary debug messages. (Ville) v4: Parameter and debug message naming improvements. Fix for link parameter check (Ville) v3: Remove cached old link parameters. Instead, disable fast link training feature when link parameters are set (Ville) v2: Readout DPCD register to check if no aux handshaking is required in link training (Ander) Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91393 Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Mika Kahola <mika.kahola@intel.com> --- drivers/gpu/drm/i915/intel_dp.c | 5 +++++ drivers/gpu/drm/i915/intel_dp_link_training.c | 3 +++ 2 files changed, 8 insertions(+)