Add counters for link training pass/failure events and a connector
debugfs entry showing these and relevant link training information. This
is meant to be used by automated testing of the driver's link retraining
and link parameter fallback functionality.
Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx>
---
.../drm/i915/display/intel_display_debugfs.c | 38 +++++++++++++++++++
.../drm/i915/display/intel_display_types.h | 3 ++
drivers/gpu/drm/i915/display/intel_dp.c | 7 +++-
.../drm/i915/display/intel_dp_link_training.c | 3 ++
4 files changed, 50 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/display/intel_display_debugfs.c b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
index 4f19d30e6972f..b25af91883584 100644
--- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
+++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
@@ -1612,6 +1612,41 @@ DEFINE_DEBUGFS_ATTRIBUTE(i915_dp_force_link_retrain_fops,
i915_dp_force_link_retrain_show,
i915_dp_force_link_retrain_write, "%llu\n");
+static int i915_dp_link_training_info_show(struct seq_file *m, void *data)
+{
+ struct intel_connector *connector = to_intel_connector(m->private);
+ struct drm_i915_private *i915 = to_i915(connector->base.dev);
+ struct intel_dp *intel_dp;
+ int ret;
+
+ ret = drm_modeset_lock_single_interruptible(&i915->drm.mode_config.connection_mutex);
+ if (ret)
+ return ret;
+
+ intel_dp = intel_connector_to_intel_dp(connector);
+
+ seq_printf(m,
+ "max_rate: %d\n"
+ "max_lane_count: %d\n"
+ "train_count: %d\n"
+ "retrain_count: %d\n"
+ "retrain_disabled: %s\n"
+ "all_failures: %d\n"
+ "seq_failures: %d\n",
+ intel_dp->link_train.max_rate,
+ intel_dp->link_train.max_lane_count,
+ intel_dp->link_train.train_count,
+ intel_dp->link_train.retrain_count,
+ str_yes_no(intel_dp->link_train.retrain_disabled),
+ intel_dp->link_train.all_failures,
+ intel_dp->link_train.seq_failures);
+
+ drm_modeset_unlock(&i915->drm.mode_config.connection_mutex);
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(i915_dp_link_training_info);
+
static int i915_dsc_output_format_show(struct seq_file *m, void *data)
{
struct intel_connector *connector = m->private;
@@ -1832,6 +1867,9 @@ void intel_connector_debugfs_add(struct intel_connector *connector)
debugfs_create_file("i915_dp_force_link_retrain", 0644, root,
connector, &i915_dp_force_link_retrain_fops);
+
+ debugfs_create_file("i915_dp_link_training_info", 0444, root,
+ connector, &i915_dp_link_training_info_fops);
}
if (DISPLAY_VER(i915) >= 11 &&
diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index 345e2883d9cfc..6ff1819fc225e 100644
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -1765,7 +1765,10 @@ struct intel_dp {
int max_lane_count;
/* Max rate for the current link */
int max_rate;
+ int train_count;
+ int retrain_count;
bool retrain_disabled;
+ int all_failures;
/* Sequential failures after a passing LT */
int seq_failures;
int force_failure;
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 28842ae51039a..0da081c457726 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -2997,6 +2997,9 @@ void intel_dp_reset_link_train_params(struct intel_dp *intel_dp)
intel_dp->link_train.max_lane_count = intel_dp_max_common_lane_count(intel_dp);
intel_dp->link_train.max_rate = intel_dp_max_common_rate(intel_dp);
intel_dp->link_train.retrain_disabled = false;
+ intel_dp->link_train.train_count = 0;
+ intel_dp->link_train.retrain_count = 0;
+ intel_dp->link_train.all_failures = 0;
intel_dp->link_train.seq_failures = 0;
}
@@ -5290,8 +5293,10 @@ static int intel_dp_retrain_link(struct intel_encoder *encoder,
}
out:
- if (ret != -EDEADLK)
+ if (ret != -EDEADLK) {
+ intel_dp->link_train.retrain_count++;
intel_dp->link_train.force_retrain = false;
+ }
return ret;
}
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
index c260299c53b7c..c43af290a4373 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -1484,6 +1484,8 @@ void intel_dp_start_link_train(struct intel_dp *intel_dp,
else
passed = intel_dp_link_train_all_phys(intel_dp, crtc_state, lttpr_count);
+ intel_dp->link_train.train_count++;
+
if (intel_dp->link_train.force_failure) {
intel_dp->link_train.force_failure--;
lt_dbg(intel_dp, DP_PHY_DPRX, "Forcing link training failure\n");
@@ -1493,6 +1495,7 @@ void intel_dp_start_link_train(struct intel_dp *intel_dp,
return;
}
+ intel_dp->link_train.all_failures++;
intel_dp->link_train.seq_failures++;
/*
--
2.43.3
