drm/i915: Unduplicate VLV phy pre pll enabling code

The code used by the DP and HDMI paths was very similar, so make them
share it. Note that this removes the write to signal level registers
from the HDMI pre pll enable path, but that's OK since those are set
in vlv_hdmi_pre_enable() function.

Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: Jim Bride <jim.bride@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1461761065-21195-9-git-send-email-ander.conselvan.de.oliveira@intel.com
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 8301a36..f59c13e 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -2791,32 +2791,9 @@
 
 static void vlv_dp_pre_pll_enable(struct intel_encoder *encoder)
 {
-	struct intel_digital_port *dport = enc_to_dig_port(&encoder->base);
-	struct drm_device *dev = encoder->base.dev;
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	struct intel_crtc *intel_crtc =
-		to_intel_crtc(encoder->base.crtc);
-	enum dpio_channel port = vlv_dport_to_channel(dport);
-	int pipe = intel_crtc->pipe;
-
 	intel_dp_prepare(encoder);
 
-	/* Program Tx lane resets to default */
-	mutex_lock(&dev_priv->sb_lock);
-	vlv_dpio_write(dev_priv, pipe, VLV_PCS_DW0(port),
-			 DPIO_PCS_TX_LANE2_RESET |
-			 DPIO_PCS_TX_LANE1_RESET);
-	vlv_dpio_write(dev_priv, pipe, VLV_PCS_DW1(port),
-			 DPIO_PCS_CLK_CRI_RXEB_EIOS_EN |
-			 DPIO_PCS_CLK_CRI_RXDIGFILTSG_EN |
-			 (1<<DPIO_PCS_CLK_DATAWIDTH_SHIFT) |
-				 DPIO_PCS_CLK_SOFT_RESET);
-
-	/* Fix up inter-pair skew failure */
-	vlv_dpio_write(dev_priv, pipe, VLV_PCS_DW12(port), 0x00750f00);
-	vlv_dpio_write(dev_priv, pipe, VLV_TX_DW11(port), 0x00001500);
-	vlv_dpio_write(dev_priv, pipe, VLV_TX_DW14(port), 0x40400000);
-	mutex_unlock(&dev_priv->sb_lock);
+	vlv_phy_pre_pll_enable(encoder);
 }
 
 static void chv_pre_enable_dp(struct intel_encoder *encoder)