[Intel-gfx] [PATCH v2 4/5] drm/i915: Pimp link training debug prints

Imre Deak imre.deak at intel.com
Wed Oct 6 16:09:02 UTC 2021


On Mon, Oct 04, 2021 at 08:05:34PM +0300, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Unify all debug prints during link training to include information
> on both the encoder and the LTTPR. We unify the format to something
> like "[ENCODER:1:FOO][LTTPR 1] Something something". Though not
> sure if those brackets around the dp_phy just make it look like
> line noise? I'll accept suggestions on better formatting.
> 
> I'm slightly on the fence about also including the connector,
> but technically only the DPRX is the SST connector (ie.
> intel_dp->attached_connector). I suppose you could think of it
> as the branch device/whatever in the topology, and we're training
> the link leading to it. So that could argue for its inclusion.
> But it's all getting a bit long alrady, so not going to do it
> I think.

Imo including the connector info eventually would be good to be able to
match these lines with those only showing the connector, or connectors
in i915_display_info etc.

> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

Reviewed-by: Imre Deak <imre.deak at intel.com>

> ---
>  .../drm/i915/display/intel_dp_link_training.c | 167 +++++++++++-------
>  1 file changed, 106 insertions(+), 61 deletions(-)
> 
> 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 5657be1461ec..18f4b469766e 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
> @@ -25,15 +25,6 @@
>  #include "intel_dp.h"
>  #include "intel_dp_link_training.h"
>  
> -static void
> -intel_dp_dump_link_status(struct drm_device *drm,
> -			  const u8 link_status[DP_LINK_STATUS_SIZE])
> -{
> -	drm_dbg_kms(drm,
> -		    "ln0_1:0x%x ln2_3:0x%x align:0x%x sink:0x%x adj_req0_1:0x%x adj_req2_3:0x%x\n",
> -		    link_status[0], link_status[1], link_status[2],
> -		    link_status[3], link_status[4], link_status[5]);
> -}
>  
>  static void intel_dp_reset_lttpr_common_caps(struct intel_dp *intel_dp)
>  {
> @@ -66,6 +57,7 @@ static u8 *intel_dp_lttpr_phy_caps(struct intel_dp *intel_dp,
>  static void intel_dp_read_lttpr_phy_caps(struct intel_dp *intel_dp,
>  					 enum drm_dp_phy dp_phy)
>  {
> +	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
>  	u8 *phy_caps = intel_dp_lttpr_phy_caps(intel_dp, dp_phy);
>  	char phy_name[10];
>  
> @@ -73,21 +65,22 @@ static void intel_dp_read_lttpr_phy_caps(struct intel_dp *intel_dp,
>  
>  	if (drm_dp_read_lttpr_phy_caps(&intel_dp->aux, dp_phy, phy_caps) < 0) {
>  		drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
> -			    "failed to read the PHY caps for %s\n",
> -			    phy_name);
> +			    "[ENCODER:%d:%s][%s] failed to read the PHY caps\n",
> +			    encoder->base.base.id, encoder->base.name, phy_name);
>  		return;
>  	}
>  
>  	drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
> -		    "%s PHY capabilities: %*ph\n",
> -		    phy_name,
> +		    "[ENCODER:%d:%s][%s] PHY capabilities: %*ph\n",
> +		    encoder->base.base.id, encoder->base.name, phy_name,
>  		    (int)sizeof(intel_dp->lttpr_phy_caps[0]),
>  		    phy_caps);
>  }
>  
>  static bool intel_dp_read_lttpr_common_caps(struct intel_dp *intel_dp)
>  {
> -	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> +	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
> +	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
>  
>  	if (intel_dp_is_edp(intel_dp))
>  		return false;
> @@ -104,7 +97,8 @@ static bool intel_dp_read_lttpr_common_caps(struct intel_dp *intel_dp)
>  		goto reset_caps;
>  
>  	drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
> -		    "LTTPR common capabilities: %*ph\n",
> +		    "[ENCODER:%d:%s] LTTPR common capabilities: %*ph\n",
> +		    encoder->base.base.id, encoder->base.name,
>  		    (int)sizeof(intel_dp->lttpr_common_caps),
>  		    intel_dp->lttpr_common_caps);
>  
> @@ -130,6 +124,8 @@ intel_dp_set_lttpr_transparent_mode(struct intel_dp *intel_dp, bool enable)
>  
>  static int intel_dp_init_lttpr(struct intel_dp *intel_dp)
>  {
> +	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
> +	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
>  	int lttpr_count;
>  	int i;
>  
> @@ -161,8 +157,9 @@ static int intel_dp_init_lttpr(struct intel_dp *intel_dp)
>  		return 0;
>  
>  	if (!intel_dp_set_lttpr_transparent_mode(intel_dp, false)) {
> -		drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
> -			    "Switching to LTTPR non-transparent LT mode failed, fall-back to transparent mode\n");
> +		drm_dbg_kms(&i915->drm,
> +			    "[ENCODER:%d:%s] Switching to LTTPR non-transparent LT mode failed, fall-back to transparent mode\n",
> +			    encoder->base.base.id, encoder->base.name);
>  
>  		intel_dp_set_lttpr_transparent_mode(intel_dp, true);
>  		intel_dp_reset_lttpr_count(intel_dp);
> @@ -366,17 +363,18 @@ intel_dp_get_adjust_train(struct intel_dp *intel_dp,
>  			  const u8 link_status[DP_LINK_STATUS_SIZE])
>  {
>  	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
> +	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
>  	char phy_name[10];
>  	int lane;
>  
> -	drm_dbg_kms(encoder->base.dev, "[ENCODER:%d:%s] lanes: %d, "
> +	drm_dbg_kms(&i915->drm, "[ENCODER:%d:%s][%s] lanes: %d, "
>  		    "vswing request: " TRAIN_REQ_FMT ", "
> -		    "pre-emphasis request: " TRAIN_REQ_FMT ", at %s\n",
> +		    "pre-emphasis request: " TRAIN_REQ_FMT "\n",
>  		    encoder->base.base.id, encoder->base.name,
> +		    intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name)),
>  		    crtc_state->lane_count,
>  		    TRAIN_REQ_VSWING_ARGS(link_status),
> -		    TRAIN_REQ_PREEMPH_ARGS(link_status),
> -		    intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name)));
> +		    TRAIN_REQ_PREEMPH_ARGS(link_status));
>  
>  	for (lane = 0; lane < 4; lane++)
>  		intel_dp->train_set[lane] =
> @@ -435,16 +433,16 @@ intel_dp_program_link_training_pattern(struct intel_dp *intel_dp,
>  				       u8 dp_train_pat)
>  {
>  	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
> -	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
> +	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
>  	u8 train_pat = intel_dp_training_pattern_symbol(dp_train_pat);
>  	char phy_name[10];
>  
>  	if (train_pat != DP_TRAINING_PATTERN_DISABLE)
> -		drm_dbg_kms(&dev_priv->drm,
> -			    "[ENCODER:%d:%s] Using DP training pattern TPS%c, at %s\n",
> +		drm_dbg_kms(&i915->drm,
> +			    "[ENCODER:%d:%s][%s] Using DP training pattern TPS%c\n",
>  			    encoder->base.base.id, encoder->base.name,
> -			    dp_training_pattern_name(train_pat),
> -			    intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name)));
> +			    intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name)),
> +			    dp_training_pattern_name(train_pat));
>  
>  	intel_dp->set_link_train(intel_dp, crtc_state, dp_train_pat);
>  }
> @@ -472,17 +470,17 @@ void intel_dp_set_signal_levels(struct intel_dp *intel_dp,
>  				enum drm_dp_phy dp_phy)
>  {
>  	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
> -	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
> +	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
>  	char phy_name[10];
>  
> -	drm_dbg_kms(&dev_priv->drm, "[ENCODER:%d:%s] lanes: %d, "
> +	drm_dbg_kms(&i915->drm, "[ENCODER:%d:%s][%s] lanes: %d, "
>  		    "vswing levels: " TRAIN_SET_FMT ", "
> -		    "pre-emphasis levels: " TRAIN_SET_FMT ", at %s\n",
> +		    "pre-emphasis levels: " TRAIN_SET_FMT "\n",
>  		    encoder->base.base.id, encoder->base.name,
> +		    intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name)),
>  		    crtc_state->lane_count,
>  		    TRAIN_SET_VSWING_ARGS(intel_dp->train_set),
> -		    TRAIN_SET_PREEMPH_ARGS(intel_dp->train_set),
> -		    intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name)));
> +		    TRAIN_SET_PREEMPH_ARGS(intel_dp->train_set));
>  
>  	if (intel_dp_phy_is_downstream_of_source(intel_dp, dp_phy))
>  		encoder->set_signal_levels(encoder, crtc_state);
> @@ -554,7 +552,8 @@ static bool
>  intel_dp_prepare_link_train(struct intel_dp *intel_dp,
>  			    const struct intel_crtc_state *crtc_state)
>  {
> -	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> +	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
> +	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
>  	u8 link_config[2];
>  	u8 link_bw, rate_select;
>  
> @@ -566,10 +565,12 @@ intel_dp_prepare_link_train(struct intel_dp *intel_dp,
>  
>  	if (link_bw)
>  		drm_dbg_kms(&i915->drm,
> -			    "Using LINK_BW_SET value %02x\n", link_bw);
> +			    "[ENCODER:%d:%s] Using LINK_BW_SET value %02x\n",
> +			    encoder->base.base.id, encoder->base.name, link_bw);
>  	else
>  		drm_dbg_kms(&i915->drm,
> -			    "Using LINK_RATE_SET value %02x\n", rate_select);
> +			    "[ENCODER:%d:%s] Using LINK_RATE_SET value %02x\n",
> +			    encoder->base.base.id, encoder->base.name, rate_select);
>  
>  	/* Write the link configuration data */
>  	link_config[0] = link_bw;
> @@ -619,6 +620,22 @@ static bool intel_dp_adjust_request_changed(int lane_count,
>  	return false;
>  }
>  
> +static void
> +intel_dp_dump_link_status(struct intel_dp *intel_dp, enum drm_dp_phy dp_phy,
> +			  const u8 link_status[DP_LINK_STATUS_SIZE])
> +{
> +	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
> +	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
> +	char phy_name[10];
> +
> +	drm_dbg_kms(&i915->drm,
> +		    "[ENCODER:%d:%s][%s] ln0_1:0x%x ln2_3:0x%x align:0x%x sink:0x%x adj_req0_1:0x%x adj_req2_3:0x%x\n",
> +		    encoder->base.base.id, encoder->base.name,
> +		    intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name)),
> +		    link_status[0], link_status[1], link_status[2],
> +		    link_status[3], link_status[4], link_status[5]);
> +}
> +
>  /*
>   * Perform the link training clock recovery phase on the given DP PHY using
>   * training pattern 1.
> @@ -628,16 +645,21 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp,
>  				      const struct intel_crtc_state *crtc_state,
>  				      enum drm_dp_phy dp_phy)
>  {
> -	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> +	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
> +	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
>  	u8 old_link_status[DP_LINK_STATUS_SIZE] = {};
>  	int voltage_tries, cr_tries, max_cr_tries;
>  	bool max_vswing_reached = false;
> +	char phy_name[10];
> +
> +	intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name));
>  
>  	/* clock recovery */
>  	if (!intel_dp_reset_link_train(intel_dp, crtc_state, dp_phy,
>  				       DP_TRAINING_PATTERN_1 |
>  				       DP_LINK_SCRAMBLING_DISABLE)) {
> -		drm_err(&i915->drm, "failed to enable link training\n");
> +		drm_err(&i915->drm, "[ENCODER:%d:%s][%s] Failed to enable link training\n",
> +			encoder->base.base.id, encoder->base.name, phy_name);
>  		return false;
>  	}
>  
> @@ -662,23 +684,29 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp,
>  
>  		if (drm_dp_dpcd_read_phy_link_status(&intel_dp->aux, dp_phy,
>  						     link_status) < 0) {
> -			drm_err(&i915->drm, "failed to get link status\n");
> +			drm_err(&i915->drm, "[ENCODER:%d:%s][%s] Failed to get link status\n",
> +				encoder->base.base.id, encoder->base.name, phy_name);
>  			return false;
>  		}
>  
>  		if (drm_dp_clock_recovery_ok(link_status, crtc_state->lane_count)) {
> -			drm_dbg_kms(&i915->drm, "clock recovery OK\n");
> +			drm_dbg_kms(&i915->drm,
> +				    "[ENCODER:%d:%s][%s] Clock recovery OK\n",
> +				    encoder->base.base.id, encoder->base.name, phy_name);
>  			return true;
>  		}
>  
>  		if (voltage_tries == 5) {
>  			drm_dbg_kms(&i915->drm,
> -				    "Same voltage tried 5 times\n");
> +				    "[ENCODER:%d:%s][%s] Same voltage tried 5 times\n",
> +				    encoder->base.base.id, encoder->base.name, phy_name);
>  			return false;
>  		}
>  
>  		if (max_vswing_reached) {
> -			drm_dbg_kms(&i915->drm, "Max Voltage Swing reached\n");
> +			drm_dbg_kms(&i915->drm,
> +				    "[ENCODER:%d:%s][%s] Max Voltage Swing reached\n",
> +				    encoder->base.base.id, encoder->base.name, phy_name);
>  			return false;
>  		}
>  
> @@ -687,7 +715,8 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp,
>  					  link_status);
>  		if (!intel_dp_update_link_train(intel_dp, crtc_state, dp_phy)) {
>  			drm_err(&i915->drm,
> -				"failed to update link training\n");
> +				"[ENCODER:%d:%s][%s] Failed to update link training\n",
> +				encoder->base.base.id, encoder->base.name, phy_name);
>  			return false;
>  		}
>  
> @@ -701,10 +730,12 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp,
>  
>  		if (intel_dp_link_max_vswing_reached(intel_dp, crtc_state))
>  			max_vswing_reached = true;
> -
>  	}
> +
>  	drm_err(&i915->drm,
> -		"Failed clock recovery %d times, giving up!\n", max_cr_tries);
> +		"[ENCODER:%d:%s][%s] Failed clock recovery %d times, giving up!\n",
> +		encoder->base.base.id, encoder->base.name, phy_name, max_cr_tries);
> +
>  	return false;
>  }
>  
> @@ -788,11 +819,15 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp,
>  					    const struct intel_crtc_state *crtc_state,
>  					    enum drm_dp_phy dp_phy)
>  {
> -	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> +	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
> +	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
>  	int tries;
>  	u32 training_pattern;
>  	u8 link_status[DP_LINK_STATUS_SIZE];
>  	bool channel_eq = false;
> +	char phy_name[10];
> +
> +	intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name));
>  
>  	training_pattern = intel_dp_training_pattern(intel_dp, crtc_state, dp_phy);
>  	/* Scrambling is disabled for TPS2/3 and enabled for TPS4 */
> @@ -802,7 +837,10 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp,
>  	/* channel equalization */
>  	if (!intel_dp_set_link_train(intel_dp, crtc_state, dp_phy,
>  				     training_pattern)) {
> -		drm_err(&i915->drm, "failed to start channel equalization\n");
> +		drm_err(&i915->drm,
> +			"[ENCODER:%d:%s][%s] Failed to start channel equalization\n",
> +			encoder->base.base.id, encoder->base.name,
> +			phy_name);
>  		return false;
>  	}
>  
> @@ -812,25 +850,28 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp,
>  		if (drm_dp_dpcd_read_phy_link_status(&intel_dp->aux, dp_phy,
>  						     link_status) < 0) {
>  			drm_err(&i915->drm,
> -				"failed to get link status\n");
> +				"[ENCODER:%d:%s][%s] Failed to get link status\n",
> +				encoder->base.base.id, encoder->base.name, phy_name);
>  			break;
>  		}
>  
>  		/* Make sure clock is still ok */
>  		if (!drm_dp_clock_recovery_ok(link_status,
>  					      crtc_state->lane_count)) {
> -			intel_dp_dump_link_status(&i915->drm, link_status);
> +			intel_dp_dump_link_status(intel_dp, dp_phy, link_status);
>  			drm_dbg_kms(&i915->drm,
> -				    "Clock recovery check failed, cannot "
> -				    "continue channel equalization\n");
> +				    "[ENCODER:%d:%s][%s] Clock recovery check failed, cannot "
> +				    "continue channel equalization\n",
> +				    encoder->base.base.id, encoder->base.name, phy_name);
>  			break;
>  		}
>  
>  		if (drm_dp_channel_eq_ok(link_status,
>  					 crtc_state->lane_count)) {
>  			channel_eq = true;
> -			drm_dbg_kms(&i915->drm, "Channel EQ done. DP Training "
> -				    "successful\n");
> +			drm_dbg_kms(&i915->drm,
> +				    "[ENCODER:%d:%s][%s] Channel EQ done. DP Training successful\n",
> +				    encoder->base.base.id, encoder->base.name, phy_name);
>  			break;
>  		}
>  
> @@ -839,16 +880,18 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp,
>  					  link_status);
>  		if (!intel_dp_update_link_train(intel_dp, crtc_state, dp_phy)) {
>  			drm_err(&i915->drm,
> -				"failed to update link training\n");
> +				"[ENCODER:%d:%s][%s] Failed to update link training\n",
> +				encoder->base.base.id, encoder->base.name, phy_name);
>  			break;
>  		}
>  	}
>  
>  	/* Try 5 times, else fail and try at lower BW */
>  	if (tries == 5) {
> -		intel_dp_dump_link_status(&i915->drm, link_status);
> +		intel_dp_dump_link_status(intel_dp, dp_phy, link_status);
>  		drm_dbg_kms(&i915->drm,
> -			    "Channel equalization failed 5 times\n");
> +			    "[ENCODER:%d:%s][%s] Channel equalization failed 5 times\n",
> +			    encoder->base.base.id, encoder->base.name, phy_name);
>  	}
>  
>  	return channel_eq;
> @@ -894,7 +937,7 @@ intel_dp_link_train_phy(struct intel_dp *intel_dp,
>  			const struct intel_crtc_state *crtc_state,
>  			enum drm_dp_phy dp_phy)
>  {
> -	struct intel_connector *intel_connector = intel_dp->attached_connector;
> +	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
>  	char phy_name[10];
>  	bool ret = false;
>  
> @@ -908,12 +951,11 @@ intel_dp_link_train_phy(struct intel_dp *intel_dp,
>  
>  out:
>  	drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
> -		    "[CONNECTOR:%d:%s] Link Training %s at link rate = %d, lane count = %d, at %s\n",
> -		    intel_connector->base.base.id,
> -		    intel_connector->base.name,
> +		    "[ENCODER:%d:%s][%s] Link Training %s at link rate = %d, lane count = %d\n",
> +		    encoder->base.base.id, encoder->base.name,
> +		    intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name)),
>  		    ret ? "passed" : "failed",
> -		    crtc_state->port_clock, crtc_state->lane_count,
> -		    intel_dp_phy_name(dp_phy, phy_name, sizeof(phy_name)));
> +		    crtc_state->port_clock, crtc_state->lane_count);
>  
>  	return ret;
>  }
> @@ -922,10 +964,13 @@ static void intel_dp_schedule_fallback_link_training(struct intel_dp *intel_dp,
>  						     const struct intel_crtc_state *crtc_state)
>  {
>  	struct intel_connector *intel_connector = intel_dp->attached_connector;
> +	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
>  
>  	if (intel_dp->hobl_active) {
>  		drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
> -			    "Link Training failed with HOBL active, not enabling it from now on");
> +			    "[ENCODER:%d:%s] Link Training failed with HOBL active, "
> +			    "not enabling it from now on",
> +			    encoder->base.base.id, encoder->base.name);
>  		intel_dp->hobl_failed = true;
>  	} else if (intel_dp_get_link_train_fallback_values(intel_dp,
>  							   crtc_state->port_clock,
> -- 
> 2.32.0
> 


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