diff mbox

[2/9] drm/i915: Split setting of vswing and pre_emph levels to separate file

Message ID 1444631122-7586-3-git-send-email-ander.conselvan.de.oliveira@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Ander Conselvan de Oliveira Oct. 12, 2015, 6:25 a.m. UTC
No functional changes, just moving code around.

Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
---
 drivers/gpu/drm/i915/Makefile                 |   1 +
 drivers/gpu/drm/i915/intel_dp.c               | 523 -------------------------
 drivers/gpu/drm/i915/intel_dp_signal_levels.c | 542 ++++++++++++++++++++++++++
 drivers/gpu/drm/i915/intel_drv.h              |   7 +
 4 files changed, 550 insertions(+), 523 deletions(-)
 create mode 100644 drivers/gpu/drm/i915/intel_dp_signal_levels.c
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index 0851de07..9cf9978 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -79,6 +79,7 @@  i915-y += dvo_ch7017.o \
 	  intel_ddi.o \
 	  intel_dp_link_training.o \
 	  intel_dp_mst.o \
+	  intel_dp_signal_levels.o \
 	  intel_dp.o \
 	  intel_dsi.o \
 	  intel_dsi_panel_vbt.o \
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 05374a7..9a159c0 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -111,13 +111,6 @@  static bool is_edp(struct intel_dp *intel_dp)
 	return intel_dig_port->base.type == INTEL_OUTPUT_EDP;
 }
 
-static struct drm_device *intel_dp_to_dev(struct intel_dp *intel_dp)
-{
-	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
-
-	return intel_dig_port->base.base.dev;
-}
-
 static struct intel_dp *intel_attached_dp(struct drm_connector *connector)
 {
 	return enc_to_intel_dp(&intel_attached_encoder(connector)->base);
@@ -3058,522 +3051,6 @@  intel_dp_get_link_status(struct intel_dp *intel_dp, uint8_t link_status[DP_LINK_
 				       DP_LINK_STATUS_SIZE) == DP_LINK_STATUS_SIZE;
 }
 
-/* These are source-specific values. */
-uint8_t
-intel_dp_voltage_max(struct intel_dp *intel_dp)
-{
-	struct drm_device *dev = intel_dp_to_dev(intel_dp);
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	enum port port = dp_to_dig_port(intel_dp)->port;
-
-	if (IS_BROXTON(dev))
-		return DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
-	else if (INTEL_INFO(dev)->gen >= 9) {
-		if (dev_priv->edp_low_vswing && port == PORT_A)
-			return DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
-		return DP_TRAIN_VOLTAGE_SWING_LEVEL_2;
-	} else if (IS_VALLEYVIEW(dev))
-		return DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
-	else if (IS_GEN7(dev) && port == PORT_A)
-		return DP_TRAIN_VOLTAGE_SWING_LEVEL_2;
-	else if (HAS_PCH_CPT(dev) && port != PORT_A)
-		return DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
-	else
-		return DP_TRAIN_VOLTAGE_SWING_LEVEL_2;
-}
-
-uint8_t
-intel_dp_pre_emphasis_max(struct intel_dp *intel_dp, uint8_t voltage_swing)
-{
-	struct drm_device *dev = intel_dp_to_dev(intel_dp);
-	enum port port = dp_to_dig_port(intel_dp)->port;
-
-	if (INTEL_INFO(dev)->gen >= 9) {
-		switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-			return DP_TRAIN_PRE_EMPH_LEVEL_3;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
-			return DP_TRAIN_PRE_EMPH_LEVEL_2;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
-			return DP_TRAIN_PRE_EMPH_LEVEL_1;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
-			return DP_TRAIN_PRE_EMPH_LEVEL_0;
-		default:
-			return DP_TRAIN_PRE_EMPH_LEVEL_0;
-		}
-	} else if (IS_HASWELL(dev) || IS_BROADWELL(dev)) {
-		switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-			return DP_TRAIN_PRE_EMPH_LEVEL_3;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
-			return DP_TRAIN_PRE_EMPH_LEVEL_2;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
-			return DP_TRAIN_PRE_EMPH_LEVEL_1;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
-		default:
-			return DP_TRAIN_PRE_EMPH_LEVEL_0;
-		}
-	} else if (IS_VALLEYVIEW(dev)) {
-		switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-			return DP_TRAIN_PRE_EMPH_LEVEL_3;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
-			return DP_TRAIN_PRE_EMPH_LEVEL_2;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
-			return DP_TRAIN_PRE_EMPH_LEVEL_1;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
-		default:
-			return DP_TRAIN_PRE_EMPH_LEVEL_0;
-		}
-	} else if (IS_GEN7(dev) && port == PORT_A) {
-		switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-			return DP_TRAIN_PRE_EMPH_LEVEL_2;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
-			return DP_TRAIN_PRE_EMPH_LEVEL_1;
-		default:
-			return DP_TRAIN_PRE_EMPH_LEVEL_0;
-		}
-	} else {
-		switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-			return DP_TRAIN_PRE_EMPH_LEVEL_2;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
-			return DP_TRAIN_PRE_EMPH_LEVEL_2;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
-			return DP_TRAIN_PRE_EMPH_LEVEL_1;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
-		default:
-			return DP_TRAIN_PRE_EMPH_LEVEL_0;
-		}
-	}
-}
-
-static uint32_t vlv_signal_levels(struct intel_dp *intel_dp)
-{
-	struct drm_device *dev = intel_dp_to_dev(intel_dp);
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	struct intel_digital_port *dport = dp_to_dig_port(intel_dp);
-	struct intel_crtc *intel_crtc =
-		to_intel_crtc(dport->base.base.crtc);
-	unsigned long demph_reg_value, preemph_reg_value,
-		uniqtranscale_reg_value;
-	uint8_t train_set = intel_dp->train_set[0];
-	enum dpio_channel port = vlv_dport_to_channel(dport);
-	int pipe = intel_crtc->pipe;
-
-	switch (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) {
-	case DP_TRAIN_PRE_EMPH_LEVEL_0:
-		preemph_reg_value = 0x0004000;
-		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-			demph_reg_value = 0x2B405555;
-			uniqtranscale_reg_value = 0x552AB83A;
-			break;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
-			demph_reg_value = 0x2B404040;
-			uniqtranscale_reg_value = 0x5548B83A;
-			break;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
-			demph_reg_value = 0x2B245555;
-			uniqtranscale_reg_value = 0x5560B83A;
-			break;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
-			demph_reg_value = 0x2B405555;
-			uniqtranscale_reg_value = 0x5598DA3A;
-			break;
-		default:
-			return 0;
-		}
-		break;
-	case DP_TRAIN_PRE_EMPH_LEVEL_1:
-		preemph_reg_value = 0x0002000;
-		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-			demph_reg_value = 0x2B404040;
-			uniqtranscale_reg_value = 0x5552B83A;
-			break;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
-			demph_reg_value = 0x2B404848;
-			uniqtranscale_reg_value = 0x5580B83A;
-			break;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
-			demph_reg_value = 0x2B404040;
-			uniqtranscale_reg_value = 0x55ADDA3A;
-			break;
-		default:
-			return 0;
-		}
-		break;
-	case DP_TRAIN_PRE_EMPH_LEVEL_2:
-		preemph_reg_value = 0x0000000;
-		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-			demph_reg_value = 0x2B305555;
-			uniqtranscale_reg_value = 0x5570B83A;
-			break;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
-			demph_reg_value = 0x2B2B4040;
-			uniqtranscale_reg_value = 0x55ADDA3A;
-			break;
-		default:
-			return 0;
-		}
-		break;
-	case DP_TRAIN_PRE_EMPH_LEVEL_3:
-		preemph_reg_value = 0x0006000;
-		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-			demph_reg_value = 0x1B405555;
-			uniqtranscale_reg_value = 0x55ADDA3A;
-			break;
-		default:
-			return 0;
-		}
-		break;
-	default:
-		return 0;
-	}
-
-	mutex_lock(&dev_priv->sb_lock);
-	vlv_dpio_write(dev_priv, pipe, VLV_TX_DW5(port), 0x00000000);
-	vlv_dpio_write(dev_priv, pipe, VLV_TX_DW4(port), demph_reg_value);
-	vlv_dpio_write(dev_priv, pipe, VLV_TX_DW2(port),
-			 uniqtranscale_reg_value);
-	vlv_dpio_write(dev_priv, pipe, VLV_TX_DW3(port), 0x0C782040);
-	vlv_dpio_write(dev_priv, pipe, VLV_PCS_DW11(port), 0x00030000);
-	vlv_dpio_write(dev_priv, pipe, VLV_PCS_DW9(port), preemph_reg_value);
-	vlv_dpio_write(dev_priv, pipe, VLV_TX_DW5(port), 0x80000000);
-	mutex_unlock(&dev_priv->sb_lock);
-
-	return 0;
-}
-
-static bool chv_need_uniq_trans_scale(uint8_t train_set)
-{
-	return (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) == DP_TRAIN_PRE_EMPH_LEVEL_0 &&
-		(train_set & DP_TRAIN_VOLTAGE_SWING_MASK) == DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
-}
-
-static uint32_t chv_signal_levels(struct intel_dp *intel_dp)
-{
-	struct drm_device *dev = intel_dp_to_dev(intel_dp);
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	struct intel_digital_port *dport = dp_to_dig_port(intel_dp);
-	struct intel_crtc *intel_crtc = to_intel_crtc(dport->base.base.crtc);
-	u32 deemph_reg_value, margin_reg_value, val;
-	uint8_t train_set = intel_dp->train_set[0];
-	enum dpio_channel ch = vlv_dport_to_channel(dport);
-	enum pipe pipe = intel_crtc->pipe;
-	int i;
-
-	switch (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) {
-	case DP_TRAIN_PRE_EMPH_LEVEL_0:
-		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-			deemph_reg_value = 128;
-			margin_reg_value = 52;
-			break;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
-			deemph_reg_value = 128;
-			margin_reg_value = 77;
-			break;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
-			deemph_reg_value = 128;
-			margin_reg_value = 102;
-			break;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
-			deemph_reg_value = 128;
-			margin_reg_value = 154;
-			/* FIXME extra to set for 1200 */
-			break;
-		default:
-			return 0;
-		}
-		break;
-	case DP_TRAIN_PRE_EMPH_LEVEL_1:
-		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-			deemph_reg_value = 85;
-			margin_reg_value = 78;
-			break;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
-			deemph_reg_value = 85;
-			margin_reg_value = 116;
-			break;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
-			deemph_reg_value = 85;
-			margin_reg_value = 154;
-			break;
-		default:
-			return 0;
-		}
-		break;
-	case DP_TRAIN_PRE_EMPH_LEVEL_2:
-		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-			deemph_reg_value = 64;
-			margin_reg_value = 104;
-			break;
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
-			deemph_reg_value = 64;
-			margin_reg_value = 154;
-			break;
-		default:
-			return 0;
-		}
-		break;
-	case DP_TRAIN_PRE_EMPH_LEVEL_3:
-		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
-		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-			deemph_reg_value = 43;
-			margin_reg_value = 154;
-			break;
-		default:
-			return 0;
-		}
-		break;
-	default:
-		return 0;
-	}
-
-	mutex_lock(&dev_priv->sb_lock);
-
-	/* Clear calc init */
-	val = vlv_dpio_read(dev_priv, pipe, VLV_PCS01_DW10(ch));
-	val &= ~(DPIO_PCS_SWING_CALC_TX0_TX2 | DPIO_PCS_SWING_CALC_TX1_TX3);
-	val &= ~(DPIO_PCS_TX1DEEMP_MASK | DPIO_PCS_TX2DEEMP_MASK);
-	val |= DPIO_PCS_TX1DEEMP_9P5 | DPIO_PCS_TX2DEEMP_9P5;
-	vlv_dpio_write(dev_priv, pipe, VLV_PCS01_DW10(ch), val);
-
-	if (intel_crtc->config->lane_count > 2) {
-		val = vlv_dpio_read(dev_priv, pipe, VLV_PCS23_DW10(ch));
-		val &= ~(DPIO_PCS_SWING_CALC_TX0_TX2 | DPIO_PCS_SWING_CALC_TX1_TX3);
-		val &= ~(DPIO_PCS_TX1DEEMP_MASK | DPIO_PCS_TX2DEEMP_MASK);
-		val |= DPIO_PCS_TX1DEEMP_9P5 | DPIO_PCS_TX2DEEMP_9P5;
-		vlv_dpio_write(dev_priv, pipe, VLV_PCS23_DW10(ch), val);
-	}
-
-	val = vlv_dpio_read(dev_priv, pipe, VLV_PCS01_DW9(ch));
-	val &= ~(DPIO_PCS_TX1MARGIN_MASK | DPIO_PCS_TX2MARGIN_MASK);
-	val |= DPIO_PCS_TX1MARGIN_000 | DPIO_PCS_TX2MARGIN_000;
-	vlv_dpio_write(dev_priv, pipe, VLV_PCS01_DW9(ch), val);
-
-	if (intel_crtc->config->lane_count > 2) {
-		val = vlv_dpio_read(dev_priv, pipe, VLV_PCS23_DW9(ch));
-		val &= ~(DPIO_PCS_TX1MARGIN_MASK | DPIO_PCS_TX2MARGIN_MASK);
-		val |= DPIO_PCS_TX1MARGIN_000 | DPIO_PCS_TX2MARGIN_000;
-		vlv_dpio_write(dev_priv, pipe, VLV_PCS23_DW9(ch), val);
-	}
-
-	/* Program swing deemph */
-	for (i = 0; i < intel_crtc->config->lane_count; i++) {
-		val = vlv_dpio_read(dev_priv, pipe, CHV_TX_DW4(ch, i));
-		val &= ~DPIO_SWING_DEEMPH9P5_MASK;
-		val |= deemph_reg_value << DPIO_SWING_DEEMPH9P5_SHIFT;
-		vlv_dpio_write(dev_priv, pipe, CHV_TX_DW4(ch, i), val);
-	}
-
-	/* Program swing margin */
-	for (i = 0; i < intel_crtc->config->lane_count; i++) {
-		val = vlv_dpio_read(dev_priv, pipe, CHV_TX_DW2(ch, i));
-
-		val &= ~DPIO_SWING_MARGIN000_MASK;
-		val |= margin_reg_value << DPIO_SWING_MARGIN000_SHIFT;
-
-		/*
-		 * Supposedly this value shouldn't matter when unique transition
-		 * scale is disabled, but in fact it does matter. Let's just
-		 * always program the same value and hope it's OK.
-		 */
-		val &= ~(0xff << DPIO_UNIQ_TRANS_SCALE_SHIFT);
-		val |= 0x9a << DPIO_UNIQ_TRANS_SCALE_SHIFT;
-
-		vlv_dpio_write(dev_priv, pipe, CHV_TX_DW2(ch, i), val);
-	}
-
-	/*
-	 * The document said it needs to set bit 27 for ch0 and bit 26
-	 * for ch1. Might be a typo in the doc.
-	 * For now, for this unique transition scale selection, set bit
-	 * 27 for ch0 and ch1.
-	 */
-	for (i = 0; i < intel_crtc->config->lane_count; i++) {
-		val = vlv_dpio_read(dev_priv, pipe, CHV_TX_DW3(ch, i));
-		if (chv_need_uniq_trans_scale(train_set))
-			val |= DPIO_TX_UNIQ_TRANS_SCALE_EN;
-		else
-			val &= ~DPIO_TX_UNIQ_TRANS_SCALE_EN;
-		vlv_dpio_write(dev_priv, pipe, CHV_TX_DW3(ch, i), val);
-	}
-
-	/* Start swing calculation */
-	val = vlv_dpio_read(dev_priv, pipe, VLV_PCS01_DW10(ch));
-	val |= DPIO_PCS_SWING_CALC_TX0_TX2 | DPIO_PCS_SWING_CALC_TX1_TX3;
-	vlv_dpio_write(dev_priv, pipe, VLV_PCS01_DW10(ch), val);
-
-	if (intel_crtc->config->lane_count > 2) {
-		val = vlv_dpio_read(dev_priv, pipe, VLV_PCS23_DW10(ch));
-		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);
-
-	return 0;
-}
-
-static uint32_t
-gen4_signal_levels(uint8_t train_set)
-{
-	uint32_t	signal_levels = 0;
-
-	switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
-	default:
-		signal_levels |= DP_VOLTAGE_0_4;
-		break;
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
-		signal_levels |= DP_VOLTAGE_0_6;
-		break;
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
-		signal_levels |= DP_VOLTAGE_0_8;
-		break;
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
-		signal_levels |= DP_VOLTAGE_1_2;
-		break;
-	}
-	switch (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) {
-	case DP_TRAIN_PRE_EMPH_LEVEL_0:
-	default:
-		signal_levels |= DP_PRE_EMPHASIS_0;
-		break;
-	case DP_TRAIN_PRE_EMPH_LEVEL_1:
-		signal_levels |= DP_PRE_EMPHASIS_3_5;
-		break;
-	case DP_TRAIN_PRE_EMPH_LEVEL_2:
-		signal_levels |= DP_PRE_EMPHASIS_6;
-		break;
-	case DP_TRAIN_PRE_EMPH_LEVEL_3:
-		signal_levels |= DP_PRE_EMPHASIS_9_5;
-		break;
-	}
-	return signal_levels;
-}
-
-/* Gen6's DP voltage swing and pre-emphasis control */
-static uint32_t
-gen6_edp_signal_levels(uint8_t train_set)
-{
-	int signal_levels = train_set & (DP_TRAIN_VOLTAGE_SWING_MASK |
-					 DP_TRAIN_PRE_EMPHASIS_MASK);
-	switch (signal_levels) {
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_0:
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_0:
-		return EDP_LINK_TRAIN_400_600MV_0DB_SNB_B;
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_1:
-		return EDP_LINK_TRAIN_400MV_3_5DB_SNB_B;
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_2:
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_2:
-		return EDP_LINK_TRAIN_400_600MV_6DB_SNB_B;
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_1:
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_1:
-		return EDP_LINK_TRAIN_600_800MV_3_5DB_SNB_B;
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_0:
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_3 | DP_TRAIN_PRE_EMPH_LEVEL_0:
-		return EDP_LINK_TRAIN_800_1200MV_0DB_SNB_B;
-	default:
-		DRM_DEBUG_KMS("Unsupported voltage swing/pre-emphasis level:"
-			      "0x%x\n", signal_levels);
-		return EDP_LINK_TRAIN_400_600MV_0DB_SNB_B;
-	}
-}
-
-/* Gen7's DP voltage swing and pre-emphasis control */
-static uint32_t
-gen7_edp_signal_levels(uint8_t train_set)
-{
-	int signal_levels = train_set & (DP_TRAIN_VOLTAGE_SWING_MASK |
-					 DP_TRAIN_PRE_EMPHASIS_MASK);
-	switch (signal_levels) {
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_0:
-		return EDP_LINK_TRAIN_400MV_0DB_IVB;
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_1:
-		return EDP_LINK_TRAIN_400MV_3_5DB_IVB;
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_2:
-		return EDP_LINK_TRAIN_400MV_6DB_IVB;
-
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_0:
-		return EDP_LINK_TRAIN_600MV_0DB_IVB;
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_1:
-		return EDP_LINK_TRAIN_600MV_3_5DB_IVB;
-
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_0:
-		return EDP_LINK_TRAIN_800MV_0DB_IVB;
-	case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_1:
-		return EDP_LINK_TRAIN_800MV_3_5DB_IVB;
-
-	default:
-		DRM_DEBUG_KMS("Unsupported voltage swing/pre-emphasis level:"
-			      "0x%x\n", signal_levels);
-		return EDP_LINK_TRAIN_500MV_0DB_IVB;
-	}
-}
-
-void
-intel_dp_update_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;
-	struct drm_device *dev = intel_dig_port->base.base.dev;
-	struct drm_i915_private *dev_priv = to_i915(dev);
-	uint32_t signal_levels, mask = 0;
-	uint8_t train_set = intel_dp->train_set[0];
-
-	if (HAS_DDI(dev)) {
-		signal_levels = ddi_signal_levels(intel_dp);
-
-		if (IS_BROXTON(dev))
-			signal_levels = 0;
-		else
-			mask = DDI_BUF_EMP_MASK;
-	} else if (IS_CHERRYVIEW(dev)) {
-		signal_levels = chv_signal_levels(intel_dp);
-	} else if (IS_VALLEYVIEW(dev)) {
-		signal_levels = vlv_signal_levels(intel_dp);
-	} else if (IS_GEN7(dev) && port == PORT_A) {
-		signal_levels = gen7_edp_signal_levels(train_set);
-		mask = EDP_LINK_TRAIN_VOL_EMP_MASK_IVB;
-	} else if (IS_GEN6(dev) && port == PORT_A) {
-		signal_levels = gen6_edp_signal_levels(train_set);
-		mask = EDP_LINK_TRAIN_VOL_EMP_MASK_SNB;
-	} else {
-		signal_levels = gen4_signal_levels(train_set);
-		mask = DP_VOLTAGE_MASK | DP_PRE_EMPHASIS_MASK;
-	}
-
-	if (mask)
-		DRM_DEBUG_KMS("Using signal levels %08x\n", signal_levels);
-
-	DRM_DEBUG_KMS("Using vswing level %d\n",
-		train_set & DP_TRAIN_VOLTAGE_SWING_MASK);
-	DRM_DEBUG_KMS("Using pre-emphasis level %d\n",
-		(train_set & DP_TRAIN_PRE_EMPHASIS_MASK) >>
-			DP_TRAIN_PRE_EMPHASIS_SHIFT);
-
-	intel_dp->DP &= ~mask;
-	intel_dp->DP |= signal_levels;
-
-	I915_WRITE(intel_dp->output_reg, intel_dp->DP);
-	POSTING_READ(intel_dp->output_reg);
-}
-
 void
 intel_dp_program_link_training_pattern(struct intel_dp *intel_dp,
 				       uint8_t dp_train_pat)
diff --git a/drivers/gpu/drm/i915/intel_dp_signal_levels.c b/drivers/gpu/drm/i915/intel_dp_signal_levels.c
new file mode 100644
index 0000000..6d21638
--- /dev/null
+++ b/drivers/gpu/drm/i915/intel_dp_signal_levels.c
@@ -0,0 +1,542 @@ 
+/*
+ * Copyright © 2008-2015 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "intel_drv.h"
+
+/* These are source-specific values. */
+uint8_t
+intel_dp_voltage_max(struct intel_dp *intel_dp)
+{
+	struct drm_device *dev = intel_dp_to_dev(intel_dp);
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	enum port port = dp_to_dig_port(intel_dp)->port;
+
+	if (IS_BROXTON(dev))
+		return DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
+	else if (INTEL_INFO(dev)->gen >= 9) {
+		if (dev_priv->edp_low_vswing && port == PORT_A)
+			return DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
+		return DP_TRAIN_VOLTAGE_SWING_LEVEL_2;
+	} else if (IS_VALLEYVIEW(dev))
+		return DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
+	else if (IS_GEN7(dev) && port == PORT_A)
+		return DP_TRAIN_VOLTAGE_SWING_LEVEL_2;
+	else if (HAS_PCH_CPT(dev) && port != PORT_A)
+		return DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
+	else
+		return DP_TRAIN_VOLTAGE_SWING_LEVEL_2;
+}
+
+uint8_t
+intel_dp_pre_emphasis_max(struct intel_dp *intel_dp, uint8_t voltage_swing)
+{
+	struct drm_device *dev = intel_dp_to_dev(intel_dp);
+	enum port port = dp_to_dig_port(intel_dp)->port;
+
+	if (INTEL_INFO(dev)->gen >= 9) {
+		switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+			return DP_TRAIN_PRE_EMPH_LEVEL_3;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
+			return DP_TRAIN_PRE_EMPH_LEVEL_2;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
+			return DP_TRAIN_PRE_EMPH_LEVEL_1;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
+			return DP_TRAIN_PRE_EMPH_LEVEL_0;
+		default:
+			return DP_TRAIN_PRE_EMPH_LEVEL_0;
+		}
+	} else if (IS_HASWELL(dev) || IS_BROADWELL(dev)) {
+		switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+			return DP_TRAIN_PRE_EMPH_LEVEL_3;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
+			return DP_TRAIN_PRE_EMPH_LEVEL_2;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
+			return DP_TRAIN_PRE_EMPH_LEVEL_1;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
+		default:
+			return DP_TRAIN_PRE_EMPH_LEVEL_0;
+		}
+	} else if (IS_VALLEYVIEW(dev)) {
+		switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+			return DP_TRAIN_PRE_EMPH_LEVEL_3;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
+			return DP_TRAIN_PRE_EMPH_LEVEL_2;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
+			return DP_TRAIN_PRE_EMPH_LEVEL_1;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
+		default:
+			return DP_TRAIN_PRE_EMPH_LEVEL_0;
+		}
+	} else if (IS_GEN7(dev) && port == PORT_A) {
+		switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+			return DP_TRAIN_PRE_EMPH_LEVEL_2;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
+			return DP_TRAIN_PRE_EMPH_LEVEL_1;
+		default:
+			return DP_TRAIN_PRE_EMPH_LEVEL_0;
+		}
+	} else {
+		switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+			return DP_TRAIN_PRE_EMPH_LEVEL_2;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
+			return DP_TRAIN_PRE_EMPH_LEVEL_2;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
+			return DP_TRAIN_PRE_EMPH_LEVEL_1;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
+		default:
+			return DP_TRAIN_PRE_EMPH_LEVEL_0;
+		}
+	}
+}
+
+static uint32_t vlv_signal_levels(struct intel_dp *intel_dp)
+{
+	struct drm_device *dev = intel_dp_to_dev(intel_dp);
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_digital_port *dport = dp_to_dig_port(intel_dp);
+	struct intel_crtc *intel_crtc =
+		to_intel_crtc(dport->base.base.crtc);
+	unsigned long demph_reg_value, preemph_reg_value,
+		uniqtranscale_reg_value;
+	uint8_t train_set = intel_dp->train_set[0];
+	enum dpio_channel port = vlv_dport_to_channel(dport);
+	int pipe = intel_crtc->pipe;
+
+	switch (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) {
+	case DP_TRAIN_PRE_EMPH_LEVEL_0:
+		preemph_reg_value = 0x0004000;
+		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+			demph_reg_value = 0x2B405555;
+			uniqtranscale_reg_value = 0x552AB83A;
+			break;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
+			demph_reg_value = 0x2B404040;
+			uniqtranscale_reg_value = 0x5548B83A;
+			break;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
+			demph_reg_value = 0x2B245555;
+			uniqtranscale_reg_value = 0x5560B83A;
+			break;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
+			demph_reg_value = 0x2B405555;
+			uniqtranscale_reg_value = 0x5598DA3A;
+			break;
+		default:
+			return 0;
+		}
+		break;
+	case DP_TRAIN_PRE_EMPH_LEVEL_1:
+		preemph_reg_value = 0x0002000;
+		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+			demph_reg_value = 0x2B404040;
+			uniqtranscale_reg_value = 0x5552B83A;
+			break;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
+			demph_reg_value = 0x2B404848;
+			uniqtranscale_reg_value = 0x5580B83A;
+			break;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
+			demph_reg_value = 0x2B404040;
+			uniqtranscale_reg_value = 0x55ADDA3A;
+			break;
+		default:
+			return 0;
+		}
+		break;
+	case DP_TRAIN_PRE_EMPH_LEVEL_2:
+		preemph_reg_value = 0x0000000;
+		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+			demph_reg_value = 0x2B305555;
+			uniqtranscale_reg_value = 0x5570B83A;
+			break;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
+			demph_reg_value = 0x2B2B4040;
+			uniqtranscale_reg_value = 0x55ADDA3A;
+			break;
+		default:
+			return 0;
+		}
+		break;
+	case DP_TRAIN_PRE_EMPH_LEVEL_3:
+		preemph_reg_value = 0x0006000;
+		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+			demph_reg_value = 0x1B405555;
+			uniqtranscale_reg_value = 0x55ADDA3A;
+			break;
+		default:
+			return 0;
+		}
+		break;
+	default:
+		return 0;
+	}
+
+	mutex_lock(&dev_priv->sb_lock);
+	vlv_dpio_write(dev_priv, pipe, VLV_TX_DW5(port), 0x00000000);
+	vlv_dpio_write(dev_priv, pipe, VLV_TX_DW4(port), demph_reg_value);
+	vlv_dpio_write(dev_priv, pipe, VLV_TX_DW2(port),
+			 uniqtranscale_reg_value);
+	vlv_dpio_write(dev_priv, pipe, VLV_TX_DW3(port), 0x0C782040);
+	vlv_dpio_write(dev_priv, pipe, VLV_PCS_DW11(port), 0x00030000);
+	vlv_dpio_write(dev_priv, pipe, VLV_PCS_DW9(port), preemph_reg_value);
+	vlv_dpio_write(dev_priv, pipe, VLV_TX_DW5(port), 0x80000000);
+	mutex_unlock(&dev_priv->sb_lock);
+
+	return 0;
+}
+
+static bool chv_need_uniq_trans_scale(uint8_t train_set)
+{
+	return (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) == DP_TRAIN_PRE_EMPH_LEVEL_0 &&
+		(train_set & DP_TRAIN_VOLTAGE_SWING_MASK) == DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
+}
+
+static uint32_t chv_signal_levels(struct intel_dp *intel_dp)
+{
+	struct drm_device *dev = intel_dp_to_dev(intel_dp);
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_digital_port *dport = dp_to_dig_port(intel_dp);
+	struct intel_crtc *intel_crtc = to_intel_crtc(dport->base.base.crtc);
+	u32 deemph_reg_value, margin_reg_value, val;
+	uint8_t train_set = intel_dp->train_set[0];
+	enum dpio_channel ch = vlv_dport_to_channel(dport);
+	enum pipe pipe = intel_crtc->pipe;
+	int i;
+
+	switch (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) {
+	case DP_TRAIN_PRE_EMPH_LEVEL_0:
+		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+			deemph_reg_value = 128;
+			margin_reg_value = 52;
+			break;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
+			deemph_reg_value = 128;
+			margin_reg_value = 77;
+			break;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
+			deemph_reg_value = 128;
+			margin_reg_value = 102;
+			break;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
+			deemph_reg_value = 128;
+			margin_reg_value = 154;
+			/* FIXME extra to set for 1200 */
+			break;
+		default:
+			return 0;
+		}
+		break;
+	case DP_TRAIN_PRE_EMPH_LEVEL_1:
+		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+			deemph_reg_value = 85;
+			margin_reg_value = 78;
+			break;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
+			deemph_reg_value = 85;
+			margin_reg_value = 116;
+			break;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
+			deemph_reg_value = 85;
+			margin_reg_value = 154;
+			break;
+		default:
+			return 0;
+		}
+		break;
+	case DP_TRAIN_PRE_EMPH_LEVEL_2:
+		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+			deemph_reg_value = 64;
+			margin_reg_value = 104;
+			break;
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
+			deemph_reg_value = 64;
+			margin_reg_value = 154;
+			break;
+		default:
+			return 0;
+		}
+		break;
+	case DP_TRAIN_PRE_EMPH_LEVEL_3:
+		switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+			deemph_reg_value = 43;
+			margin_reg_value = 154;
+			break;
+		default:
+			return 0;
+		}
+		break;
+	default:
+		return 0;
+	}
+
+	mutex_lock(&dev_priv->sb_lock);
+
+	/* Clear calc init */
+	val = vlv_dpio_read(dev_priv, pipe, VLV_PCS01_DW10(ch));
+	val &= ~(DPIO_PCS_SWING_CALC_TX0_TX2 | DPIO_PCS_SWING_CALC_TX1_TX3);
+	val &= ~(DPIO_PCS_TX1DEEMP_MASK | DPIO_PCS_TX2DEEMP_MASK);
+	val |= DPIO_PCS_TX1DEEMP_9P5 | DPIO_PCS_TX2DEEMP_9P5;
+	vlv_dpio_write(dev_priv, pipe, VLV_PCS01_DW10(ch), val);
+
+	if (intel_crtc->config->lane_count > 2) {
+		val = vlv_dpio_read(dev_priv, pipe, VLV_PCS23_DW10(ch));
+		val &= ~(DPIO_PCS_SWING_CALC_TX0_TX2 | DPIO_PCS_SWING_CALC_TX1_TX3);
+		val &= ~(DPIO_PCS_TX1DEEMP_MASK | DPIO_PCS_TX2DEEMP_MASK);
+		val |= DPIO_PCS_TX1DEEMP_9P5 | DPIO_PCS_TX2DEEMP_9P5;
+		vlv_dpio_write(dev_priv, pipe, VLV_PCS23_DW10(ch), val);
+	}
+
+	val = vlv_dpio_read(dev_priv, pipe, VLV_PCS01_DW9(ch));
+	val &= ~(DPIO_PCS_TX1MARGIN_MASK | DPIO_PCS_TX2MARGIN_MASK);
+	val |= DPIO_PCS_TX1MARGIN_000 | DPIO_PCS_TX2MARGIN_000;
+	vlv_dpio_write(dev_priv, pipe, VLV_PCS01_DW9(ch), val);
+
+	if (intel_crtc->config->lane_count > 2) {
+		val = vlv_dpio_read(dev_priv, pipe, VLV_PCS23_DW9(ch));
+		val &= ~(DPIO_PCS_TX1MARGIN_MASK | DPIO_PCS_TX2MARGIN_MASK);
+		val |= DPIO_PCS_TX1MARGIN_000 | DPIO_PCS_TX2MARGIN_000;
+		vlv_dpio_write(dev_priv, pipe, VLV_PCS23_DW9(ch), val);
+	}
+
+	/* Program swing deemph */
+	for (i = 0; i < intel_crtc->config->lane_count; i++) {
+		val = vlv_dpio_read(dev_priv, pipe, CHV_TX_DW4(ch, i));
+		val &= ~DPIO_SWING_DEEMPH9P5_MASK;
+		val |= deemph_reg_value << DPIO_SWING_DEEMPH9P5_SHIFT;
+		vlv_dpio_write(dev_priv, pipe, CHV_TX_DW4(ch, i), val);
+	}
+
+	/* Program swing margin */
+	for (i = 0; i < intel_crtc->config->lane_count; i++) {
+		val = vlv_dpio_read(dev_priv, pipe, CHV_TX_DW2(ch, i));
+
+		val &= ~DPIO_SWING_MARGIN000_MASK;
+		val |= margin_reg_value << DPIO_SWING_MARGIN000_SHIFT;
+
+		/*
+		 * Supposedly this value shouldn't matter when unique transition
+		 * scale is disabled, but in fact it does matter. Let's just
+		 * always program the same value and hope it's OK.
+		 */
+		val &= ~(0xff << DPIO_UNIQ_TRANS_SCALE_SHIFT);
+		val |= 0x9a << DPIO_UNIQ_TRANS_SCALE_SHIFT;
+
+		vlv_dpio_write(dev_priv, pipe, CHV_TX_DW2(ch, i), val);
+	}
+
+	/*
+	 * The document said it needs to set bit 27 for ch0 and bit 26
+	 * for ch1. Might be a typo in the doc.
+	 * For now, for this unique transition scale selection, set bit
+	 * 27 for ch0 and ch1.
+	 */
+	for (i = 0; i < intel_crtc->config->lane_count; i++) {
+		val = vlv_dpio_read(dev_priv, pipe, CHV_TX_DW3(ch, i));
+		if (chv_need_uniq_trans_scale(train_set))
+			val |= DPIO_TX_UNIQ_TRANS_SCALE_EN;
+		else
+			val &= ~DPIO_TX_UNIQ_TRANS_SCALE_EN;
+		vlv_dpio_write(dev_priv, pipe, CHV_TX_DW3(ch, i), val);
+	}
+
+	/* Start swing calculation */
+	val = vlv_dpio_read(dev_priv, pipe, VLV_PCS01_DW10(ch));
+	val |= DPIO_PCS_SWING_CALC_TX0_TX2 | DPIO_PCS_SWING_CALC_TX1_TX3;
+	vlv_dpio_write(dev_priv, pipe, VLV_PCS01_DW10(ch), val);
+
+	if (intel_crtc->config->lane_count > 2) {
+		val = vlv_dpio_read(dev_priv, pipe, VLV_PCS23_DW10(ch));
+		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);
+
+	return 0;
+}
+
+static uint32_t
+gen4_signal_levels(uint8_t train_set)
+{
+	uint32_t	signal_levels = 0;
+
+	switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
+	default:
+		signal_levels |= DP_VOLTAGE_0_4;
+		break;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
+		signal_levels |= DP_VOLTAGE_0_6;
+		break;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
+		signal_levels |= DP_VOLTAGE_0_8;
+		break;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
+		signal_levels |= DP_VOLTAGE_1_2;
+		break;
+	}
+	switch (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) {
+	case DP_TRAIN_PRE_EMPH_LEVEL_0:
+	default:
+		signal_levels |= DP_PRE_EMPHASIS_0;
+		break;
+	case DP_TRAIN_PRE_EMPH_LEVEL_1:
+		signal_levels |= DP_PRE_EMPHASIS_3_5;
+		break;
+	case DP_TRAIN_PRE_EMPH_LEVEL_2:
+		signal_levels |= DP_PRE_EMPHASIS_6;
+		break;
+	case DP_TRAIN_PRE_EMPH_LEVEL_3:
+		signal_levels |= DP_PRE_EMPHASIS_9_5;
+		break;
+	}
+	return signal_levels;
+}
+
+/* Gen6's DP voltage swing and pre-emphasis control */
+static uint32_t
+gen6_edp_signal_levels(uint8_t train_set)
+{
+	int signal_levels = train_set & (DP_TRAIN_VOLTAGE_SWING_MASK |
+					 DP_TRAIN_PRE_EMPHASIS_MASK);
+	switch (signal_levels) {
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_0:
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_0:
+		return EDP_LINK_TRAIN_400_600MV_0DB_SNB_B;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_1:
+		return EDP_LINK_TRAIN_400MV_3_5DB_SNB_B;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_2:
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_2:
+		return EDP_LINK_TRAIN_400_600MV_6DB_SNB_B;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_1:
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_1:
+		return EDP_LINK_TRAIN_600_800MV_3_5DB_SNB_B;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_0:
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_3 | DP_TRAIN_PRE_EMPH_LEVEL_0:
+		return EDP_LINK_TRAIN_800_1200MV_0DB_SNB_B;
+	default:
+		DRM_DEBUG_KMS("Unsupported voltage swing/pre-emphasis level:"
+			      "0x%x\n", signal_levels);
+		return EDP_LINK_TRAIN_400_600MV_0DB_SNB_B;
+	}
+}
+
+/* Gen7's DP voltage swing and pre-emphasis control */
+static uint32_t
+gen7_edp_signal_levels(uint8_t train_set)
+{
+	int signal_levels = train_set & (DP_TRAIN_VOLTAGE_SWING_MASK |
+					 DP_TRAIN_PRE_EMPHASIS_MASK);
+	switch (signal_levels) {
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_0:
+		return EDP_LINK_TRAIN_400MV_0DB_IVB;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_1:
+		return EDP_LINK_TRAIN_400MV_3_5DB_IVB;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_2:
+		return EDP_LINK_TRAIN_400MV_6DB_IVB;
+
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_0:
+		return EDP_LINK_TRAIN_600MV_0DB_IVB;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_1:
+		return EDP_LINK_TRAIN_600MV_3_5DB_IVB;
+
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_0:
+		return EDP_LINK_TRAIN_800MV_0DB_IVB;
+	case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_1:
+		return EDP_LINK_TRAIN_800MV_3_5DB_IVB;
+
+	default:
+		DRM_DEBUG_KMS("Unsupported voltage swing/pre-emphasis level:"
+			      "0x%x\n", signal_levels);
+		return EDP_LINK_TRAIN_500MV_0DB_IVB;
+	}
+}
+
+void
+intel_dp_update_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;
+	struct drm_device *dev = intel_dig_port->base.base.dev;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	uint32_t signal_levels, mask = 0;
+	uint8_t train_set = intel_dp->train_set[0];
+
+	if (HAS_DDI(dev)) {
+		signal_levels = ddi_signal_levels(intel_dp);
+
+		if (IS_BROXTON(dev))
+			signal_levels = 0;
+		else
+			mask = DDI_BUF_EMP_MASK;
+	} else if (IS_CHERRYVIEW(dev)) {
+		signal_levels = chv_signal_levels(intel_dp);
+	} else if (IS_VALLEYVIEW(dev)) {
+		signal_levels = vlv_signal_levels(intel_dp);
+	} else if (IS_GEN7(dev) && port == PORT_A) {
+		signal_levels = gen7_edp_signal_levels(train_set);
+		mask = EDP_LINK_TRAIN_VOL_EMP_MASK_IVB;
+	} else if (IS_GEN6(dev) && port == PORT_A) {
+		signal_levels = gen6_edp_signal_levels(train_set);
+		mask = EDP_LINK_TRAIN_VOL_EMP_MASK_SNB;
+	} else {
+		signal_levels = gen4_signal_levels(train_set);
+		mask = DP_VOLTAGE_MASK | DP_PRE_EMPHASIS_MASK;
+	}
+
+	if (mask)
+		DRM_DEBUG_KMS("Using signal levels %08x\n", signal_levels);
+
+	DRM_DEBUG_KMS("Using vswing level %d\n",
+		train_set & DP_TRAIN_VOLTAGE_SWING_MASK);
+	DRM_DEBUG_KMS("Using pre-emphasis level %d\n",
+		(train_set & DP_TRAIN_PRE_EMPHASIS_MASK) >>
+			DP_TRAIN_PRE_EMPHASIS_SHIFT);
+
+	intel_dp->DP &= ~mask;
+	intel_dp->DP |= signal_levels;
+
+	I915_WRITE(intel_dp->output_reg, intel_dp->DP);
+	POSTING_READ(intel_dp->output_reg);
+}
+
+
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 298050f..d341210 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -936,6 +936,13 @@  dp_to_dig_port(struct intel_dp *intel_dp)
 	return container_of(intel_dp, struct intel_digital_port, dp);
 }
 
+static inline struct drm_device *intel_dp_to_dev(struct intel_dp *intel_dp)
+{
+	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
+
+	return intel_dig_port->base.base.dev;
+}
+
 static inline struct intel_digital_port *
 hdmi_to_dig_port(struct intel_hdmi *intel_hdmi)
 {