Commit c43027a9 authored by Imre Deak's avatar Imre Deak
Browse files

drm/i915: Factor out a helper to disable the DPCD training pattern 



To prepare for a follow-up LTTPR change factor out a helper to disable
the training pattern in DPCD. We'll need to do this for each LTTPR
(without programming the port to output the idle pattern) when training
in LTTPR non-transparent mode.

While at it also move the disable-link-training logic from
intel_dp_set_link_train() to intel_dp_stop_link_train(), since the
latter is the only user of this.

v2:
- Move the disable-link-training logic to intel_dp_stop_link_train()
  (Ville)

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: default avatarImre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201007170917.1764556-4-imre.deak@intel.com
parent 0a5991f5

drivers/gpu/drm/i915/display/intel_dp_link_training.c

+17 −16
Original line number Diff line number Diff line
@@ -94,26 +94,18 @@ intel_dp_set_link_train(struct intel_dp *intel_dp, 
			u8 dp_train_pat)

{

	u8 buf[sizeof(intel_dp->train_set) + 1];

	int ret, len;

	int len;



	intel_dp_program_link_training_pattern(intel_dp, crtc_state,

					       dp_train_pat);



	buf[0] = dp_train_pat;

	if (intel_dp_training_pattern_symbol(dp_train_pat) ==

	    DP_TRAINING_PATTERN_DISABLE) {

		/* don't write DP_TRAINING_LANEx_SET on disable */

		len = 1;

	} else {

	/* DP_TRAINING_LANEx_SET follow DP_TRAINING_PATTERN_SET */

	memcpy(buf + 1, intel_dp->train_set, crtc_state->lane_count);

	len = crtc_state->lane_count + 1;

	}



	ret = drm_dp_dpcd_write(&intel_dp->aux, DP_TRAINING_PATTERN_SET,

				buf, len);



	return ret == len;

	return drm_dp_dpcd_write(&intel_dp->aux, DP_TRAINING_PATTERN_SET,

				 buf, len) == len;

}



static bool
@@ -406,6 +398,13 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp, 
	return channel_eq;

}



static bool intel_dp_disable_dpcd_training_pattern(struct intel_dp *intel_dp)

{

	u8 val = DP_TRAINING_PATTERN_DISABLE;



	return drm_dp_dpcd_write(&intel_dp->aux, DP_TRAINING_PATTERN_SET, &val, 1) == 1;

}



/**

 * intel_dp_stop_link_train - stop link training

 * @intel_dp: DP struct
@@ -427,8 +426,10 @@ void intel_dp_stop_link_train(struct intel_dp *intel_dp, 
{

	intel_dp->link_trained = true;



	intel_dp_set_link_train(intel_dp, crtc_state,

	intel_dp_program_link_training_pattern(intel_dp,

					       crtc_state,

					       DP_TRAINING_PATTERN_DISABLE);

	intel_dp_disable_dpcd_training_pattern(intel_dp);

}



static bool

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