drm/i915: Don't bypass LRC on CHV

The docs are unclear as usual, so it's not clear whether LRC should be
bypassed, performed normally or GRC code should be used as the LRC code.
Some old docs stated that LRC bypass ought to be used, more recent ones
no longer say that. Some docs indicated that we could use GRC as the LRC
code on CHV, but the BIOS doesn't do that, so let's not do it either.

Besides to enable LRC bypass properly, I believe we should set the bit
already before deasserting cmnreset.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Deepak S<deepak.s@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_dp.c

@@ -3417,11 +3417,6 @@ static uint32_t chv_signal_levels(struct intel_dp *intel_dp)
 		vlv_dpio_write(dev_priv, pipe, VLV_PCS23_DW10(ch), val);
 	}
 
-	/* LRC Bypass */
-	val = vlv_dpio_read(dev_priv, pipe, CHV_CMN_DW30);
-	val |= DPIO_LRC_BYPASS;
-	vlv_dpio_write(dev_priv, pipe, CHV_CMN_DW30, val);
-
 	mutex_unlock(&dev_priv->sb_lock);
 
 	return 0;

drivers/gpu/drm/i915/intel_hdmi.c

@@ -1952,11 +1952,6 @@ static void chv_hdmi_pre_enable(struct intel_encoder *encoder)
 	val |= DPIO_PCS_SWING_CALC_TX0_TX2 | DPIO_PCS_SWING_CALC_TX1_TX3;
 	vlv_dpio_write(dev_priv, pipe, VLV_PCS23_DW10(ch), val);
 
-	/* LRC Bypass */
-	val = vlv_dpio_read(dev_priv, pipe, CHV_CMN_DW30);
-	val |= DPIO_LRC_BYPASS;
-	vlv_dpio_write(dev_priv, pipe, CHV_CMN_DW30, val);
-
 	mutex_unlock(&dev_priv->sb_lock);
 
 	intel_hdmi->set_infoframes(&encoder->base,