Add a connector debugfs entry to force retrain an active link. This can be used to test both custom link parameters (previously set via the target link lane count/rate entries) or link train failure scenarios (previously forced via the force-failure entry). The entry will autoreset after the link-retrain is complete.
v2: Add the entry from intel_dp_link_training.c (Jani) Cc: Jani Nikula <[email protected]> Signed-off-by: Imre Deak <[email protected]> --- .../drm/i915/display/intel_display_types.h | 1 + drivers/gpu/drm/i915/display/intel_dp.c | 18 +++++-- .../drm/i915/display/intel_dp_link_training.c | 47 +++++++++++++++++++ 3 files changed, 61 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h index dbe1468fe471d..52c69c7eb52f5 100644 --- a/drivers/gpu/drm/i915/display/intel_display_types.h +++ b/drivers/gpu/drm/i915/display/intel_display_types.h @@ -1771,6 +1771,7 @@ struct intel_dp { /* Sequential link training failures after a passing LT */ int seq_train_failures; int force_train_failure; + bool force_retrain; } link; bool reset_link_params; int mso_link_count; diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index cf4a768fccd15..895074d548671 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -5042,7 +5042,7 @@ intel_dp_check_mst_status(struct intel_dp *intel_dp) drm_dp_mst_hpd_irq_send_new_request(&intel_dp->mst_mgr); } - if (!link_ok) + if (!link_ok || intel_dp->link.force_retrain) intel_ddi_queue_link_check(dig_port, 0); return !reprobe_needed; @@ -5091,6 +5091,9 @@ intel_dp_needs_link_retrain(struct intel_dp *intel_dp) if (intel_psr_enabled(intel_dp)) return false; + if (intel_dp->link.force_retrain) + return true; + if (drm_dp_dpcd_read_phy_link_status(&intel_dp->aux, DP_PHY_DPRX, link_status) < 0) return false; @@ -5237,8 +5240,9 @@ int intel_dp_retrain_link(struct intel_encoder *encoder, if (!intel_dp_needs_link_retrain(intel_dp)) return 0; - drm_dbg_kms(&dev_priv->drm, "[ENCODER:%d:%s] retraining link\n", - encoder->base.base.id, encoder->base.name); + drm_dbg_kms(&dev_priv->drm, "[ENCODER:%d:%s] retraining link (forced %s)\n", + encoder->base.base.id, encoder->base.name, + str_yes_no(intel_dp->link.force_retrain)); for_each_intel_crtc_in_pipe_mask(&dev_priv->drm, crtc, pipe_mask) { const struct intel_crtc_state *crtc_state = @@ -5266,7 +5270,7 @@ int intel_dp_retrain_link(struct intel_encoder *encoder, encoder->base.base.id, encoder->base.name, ERR_PTR(ret)); - return ret; + goto out; } for_each_intel_crtc_in_pipe_mask(&dev_priv->drm, crtc, pipe_mask) { @@ -5293,7 +5297,11 @@ int intel_dp_retrain_link(struct intel_encoder *encoder, intel_crtc_pch_transcoder(crtc), true); } - return 0; +out: + if (ret != -EDEADLK) + intel_dp->link.force_retrain = false; + + return ret; } static int intel_dp_prep_phy_test(struct intel_dp *intel_dp, 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 b40148a42f442..6fac8421a6918 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c @@ -26,6 +26,7 @@ #include "intel_dp.h" #include "intel_dp_link_training.h" #include "intel_ddi.h" +#include "intel_hotplug.h" #include "intel_panel.h" #define LT_MSG_PREFIX "[CONNECTOR:%d:%s][ENCODER:%d:%s][%s] " @@ -1846,6 +1847,49 @@ DEFINE_DEBUGFS_ATTRIBUTE(i915_dp_force_link_training_failure_fops, i915_dp_force_link_training_failure_show, i915_dp_force_link_training_failure_write, "%llu\n"); +static int i915_dp_force_link_retrain_show(void *data, u64 *val) +{ + struct intel_connector *connector = to_intel_connector(data); + struct drm_i915_private *i915 = to_i915(connector->base.dev); + struct intel_dp *intel_dp; + int err; + + err = drm_modeset_lock_single_interruptible(&i915->drm.mode_config.connection_mutex); + if (err) + return err; + + intel_dp = intel_connector_to_intel_dp(connector); + *val = intel_dp->link.force_retrain; + + drm_modeset_unlock(&i915->drm.mode_config.connection_mutex); + + return 0; +} + +static int i915_dp_force_link_retrain_write(void *data, u64 val) +{ + struct intel_connector *connector = to_intel_connector(data); + struct drm_i915_private *i915 = to_i915(connector->base.dev); + struct intel_dp *intel_dp; + int err; + + err = drm_modeset_lock_single_interruptible(&i915->drm.mode_config.connection_mutex); + if (err) + return err; + + intel_dp = intel_connector_to_intel_dp(connector); + + intel_dp->link.force_retrain = val; + intel_hpd_trigger_irq(dp_to_dig_port(intel_dp)); + + drm_modeset_unlock(&i915->drm.mode_config.connection_mutex); + + return 0; +} +DEFINE_DEBUGFS_ATTRIBUTE(i915_dp_force_link_retrain_fops, + i915_dp_force_link_retrain_show, + i915_dp_force_link_retrain_write, "%llu\n"); + void intel_dp_link_training_debugfs_add(struct intel_connector *connector) { struct dentry *root = connector->base.debugfs_entry; @@ -1868,4 +1912,7 @@ void intel_dp_link_training_debugfs_add(struct intel_connector *connector) debugfs_create_file("i915_dp_force_link_training_failure", 0644, root, connector, &i915_dp_force_link_training_failure_fops); + + debugfs_create_file("i915_dp_force_link_retrain", 0644, root, + connector, &i915_dp_force_link_retrain_fops); } -- 2.43.3
