Commit f4eb692e authored by Ander Conselvan de Oliveira's avatar Ander Conselvan de Oliveira
Browse files

drm/i915: Don't pass *DP around to link training functions 



It just makes the code more confusing, so just reference intel_dp_>DP
directly.

Note that this also fix a bug where the value of intel_dp->DP could be
different than the last value written to the hw, due to an early return
that would skip the 'intel_dp->DP = DP' line.

v2: Don't preserve old DP value on failure. (Sivakumar)
  - Don't call drm_dp_clock_recovery_ok() twice. (Sivakumar)
  - Keep return type of clock recovery and channel equalization
    functions as void. (Ander)

v3: Remove DP parameter from intel_dp_set_signal_levels(). (Sivakumar)

Signed-off-by: default avatarAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: default avatarSivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1445594525-7174-2-git-send-email-ander.conselvan.de.oliveira@intel.com
parent 00ce5c8a

drivers/gpu/drm/i915/intel_dp.c

+20 −27
Original line number Diff line number Diff line
@@ -3552,7 +3552,7 @@ gen7_edp_signal_levels(uint8_t train_set) 


/* Properly updates "DP" with the correct signal levels. */

static void

intel_dp_set_signal_levels(struct intel_dp *intel_dp, uint32_t *DP)

intel_dp_set_signal_levels(struct intel_dp *intel_dp)

{

	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);

	enum port port = intel_dig_port->port;
@@ -3591,12 +3591,11 @@ intel_dp_set_signal_levels(struct intel_dp *intel_dp, uint32_t *DP) 
		(train_set & DP_TRAIN_PRE_EMPHASIS_MASK) >>

			DP_TRAIN_PRE_EMPHASIS_SHIFT);



	*DP = (*DP & ~mask) | signal_levels;

	intel_dp->DP = (intel_dp->DP & ~mask) | signal_levels;

}



static bool

intel_dp_set_link_train(struct intel_dp *intel_dp,

			uint32_t *DP,

			uint8_t dp_train_pat)

{

	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
@@ -3605,9 +3604,9 @@ intel_dp_set_link_train(struct intel_dp *intel_dp, 
	uint8_t buf[sizeof(intel_dp->train_set) + 1];

	int ret, len;



	_intel_dp_set_link_train(intel_dp, DP, dp_train_pat);

	_intel_dp_set_link_train(intel_dp, &intel_dp->DP, dp_train_pat);



	I915_WRITE(intel_dp->output_reg, *DP);

	I915_WRITE(intel_dp->output_reg, intel_dp->DP);

	POSTING_READ(intel_dp->output_reg);



	buf[0] = dp_train_pat;
@@ -3628,17 +3627,17 @@ intel_dp_set_link_train(struct intel_dp *intel_dp, 
}



static bool

intel_dp_reset_link_train(struct intel_dp *intel_dp, uint32_t *DP,

intel_dp_reset_link_train(struct intel_dp *intel_dp,

			uint8_t dp_train_pat)

{

	if (!intel_dp->train_set_valid)

		memset(intel_dp->train_set, 0, sizeof(intel_dp->train_set));

	intel_dp_set_signal_levels(intel_dp, DP);

	return intel_dp_set_link_train(intel_dp, DP, dp_train_pat);

	intel_dp_set_signal_levels(intel_dp);

	return intel_dp_set_link_train(intel_dp, dp_train_pat);

}



static bool

intel_dp_update_link_train(struct intel_dp *intel_dp, uint32_t *DP,

intel_dp_update_link_train(struct intel_dp *intel_dp,

			   const uint8_t link_status[DP_LINK_STATUS_SIZE])

{

	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
@@ -3647,9 +3646,9 @@ intel_dp_update_link_train(struct intel_dp *intel_dp, uint32_t *DP, 
	int ret;



	intel_get_adjust_train(intel_dp, link_status);

	intel_dp_set_signal_levels(intel_dp, DP);

	intel_dp_set_signal_levels(intel_dp);



	I915_WRITE(intel_dp->output_reg, *DP);

	I915_WRITE(intel_dp->output_reg, intel_dp->DP);

	POSTING_READ(intel_dp->output_reg);



	ret = drm_dp_dpcd_write(&intel_dp->aux, DP_TRAINING_LANE0_SET,
@@ -3698,7 +3697,6 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp) 
	int i;

	uint8_t voltage;

	int voltage_tries, loop_tries;

	uint32_t DP = intel_dp->DP;

	uint8_t link_config[2];

	uint8_t link_bw, rate_select;
@@ -3722,10 +3720,10 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp) 
	link_config[1] = DP_SET_ANSI_8B10B;

	drm_dp_dpcd_write(&intel_dp->aux, DP_DOWNSPREAD_CTRL, link_config, 2);



	DP |= DP_PORT_EN;

	intel_dp->DP |= DP_PORT_EN;



	/* clock recovery */

	if (!intel_dp_reset_link_train(intel_dp, &DP,

	if (!intel_dp_reset_link_train(intel_dp,

				       DP_TRAINING_PATTERN_1 |

				       DP_LINK_SCRAMBLING_DISABLE)) {

		DRM_ERROR("failed to enable link training\n");
@@ -3757,7 +3755,7 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp) 
			DRM_DEBUG_KMS("clock recovery not ok, reset");

			/* clear the flag as we are not reusing train set */

			intel_dp->train_set_valid = false;

			if (!intel_dp_reset_link_train(intel_dp, &DP,

			if (!intel_dp_reset_link_train(intel_dp,

						       DP_TRAINING_PATTERN_1 |

						       DP_LINK_SCRAMBLING_DISABLE)) {

				DRM_ERROR("failed to enable link training\n");
@@ -3776,7 +3774,7 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp) 
				DRM_ERROR("too many full retries, give up\n");

				break;

			}

			intel_dp_reset_link_train(intel_dp, &DP,

			intel_dp_reset_link_train(intel_dp,

						  DP_TRAINING_PATTERN_1 |

						  DP_LINK_SCRAMBLING_DISABLE);

			voltage_tries = 0;
@@ -3795,13 +3793,11 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp) 
		voltage = intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;



		/* Update training set as requested by target */

		if (!intel_dp_update_link_train(intel_dp, &DP, link_status)) {

		if (!intel_dp_update_link_train(intel_dp, link_status)) {

			DRM_ERROR("failed to update link training\n");

			break;

		}

	}



	intel_dp->DP = DP;

}



static void
@@ -3811,7 +3807,6 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp) 
	struct drm_device *dev = dig_port->base.base.dev;

	bool channel_eq = false;

	int tries, cr_tries;

	uint32_t DP = intel_dp->DP;

	uint32_t training_pattern = DP_TRAINING_PATTERN_2;



	/*
@@ -3830,7 +3825,7 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp) 
		DRM_ERROR("5.4 Gbps link rate without HBR2/TPS3 support\n");



	/* channel equalization */

	if (!intel_dp_set_link_train(intel_dp, &DP,

	if (!intel_dp_set_link_train(intel_dp,

				     training_pattern |

				     DP_LINK_SCRAMBLING_DISABLE)) {

		DRM_ERROR("failed to start channel equalization\n");
@@ -3859,7 +3854,7 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp) 
					      intel_dp->lane_count)) {

			intel_dp->train_set_valid = false;

			intel_dp_link_training_clock_recovery(intel_dp);

			intel_dp_set_link_train(intel_dp, &DP,

			intel_dp_set_link_train(intel_dp,

						training_pattern |

						DP_LINK_SCRAMBLING_DISABLE);

			cr_tries++;
@@ -3876,7 +3871,7 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp) 
		if (tries > 5) {

			intel_dp->train_set_valid = false;

			intel_dp_link_training_clock_recovery(intel_dp);

			intel_dp_set_link_train(intel_dp, &DP,

			intel_dp_set_link_train(intel_dp,

						training_pattern |

						DP_LINK_SCRAMBLING_DISABLE);

			tries = 0;
@@ -3885,7 +3880,7 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp) 
		}



		/* Update training set as requested by target */

		if (!intel_dp_update_link_train(intel_dp, &DP, link_status)) {

		if (!intel_dp_update_link_train(intel_dp, link_status)) {

			DRM_ERROR("failed to update link training\n");

			break;

		}
@@ -3894,8 +3889,6 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp) 


	intel_dp_set_idle_link_train(intel_dp);



	intel_dp->DP = DP;



	if (channel_eq) {

		intel_dp->train_set_valid = true;

		DRM_DEBUG_KMS("Channel EQ done. DP Training successful\n");
@@ -3904,7 +3897,7 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp) 


void intel_dp_stop_link_train(struct intel_dp *intel_dp)

{

	intel_dp_set_link_train(intel_dp, &intel_dp->DP,

	intel_dp_set_link_train(intel_dp,

				DP_TRAINING_PATTERN_DISABLE);

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE