drm/i915: Hook up Ivybridge eDP

The Ivybridge eDP control register looks like a cross between a
Cougarpoint PCH DP control register and a Sandybridge eDP control
register.

Where things trivially match, share the code. Where there are any
tricky bits, just split things out into two obviously separate code paths.
Signed-off-by: Keith Packard <keithp@keithp.com>
Tested-by: Fang Xun <xunx.fang@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=41991

drivers/gpu/drm/i915/i915_reg.h

@@ -3447,6 +3447,24 @@
 #define  EDP_LINK_TRAIN_800_1200MV_0DB_SNB_B	(0x38<<22)
 #define  EDP_LINK_TRAIN_VOL_EMP_MASK_SNB	(0x3f<<22)
 
+/* IVB */
+#define EDP_LINK_TRAIN_400MV_0DB_IVB		(0x24 <<22)
+#define EDP_LINK_TRAIN_400MV_3_5DB_IVB		(0x2a <<22)
+#define EDP_LINK_TRAIN_400MV_6DB_IVB		(0x2f <<22)
+#define EDP_LINK_TRAIN_600MV_0DB_IVB		(0x30 <<22)
+#define EDP_LINK_TRAIN_600MV_3_5DB_IVB		(0x36 <<22)
+#define EDP_LINK_TRAIN_800MV_0DB_IVB		(0x38 <<22)
+#define EDP_LINK_TRAIN_800MV_3_5DB_IVB		(0x33 <<22)
+
+/* legacy values */
+#define EDP_LINK_TRAIN_500MV_0DB_IVB		(0x00 <<22)
+#define EDP_LINK_TRAIN_1000MV_0DB_IVB		(0x20 <<22)
+#define EDP_LINK_TRAIN_500MV_3_5DB_IVB		(0x02 <<22)
+#define EDP_LINK_TRAIN_1000MV_3_5DB_IVB		(0x22 <<22)
+#define EDP_LINK_TRAIN_1000MV_6DB_IVB		(0x23 <<22)
+
+#define  EDP_LINK_TRAIN_VOL_EMP_MASK_IVB	(0x3f<<22)
+
 #define  FORCEWAKE				0xA18C
 #define  FORCEWAKE_ACK				0x130090
 #define  FORCEWAKE_MT				0xa188 /* multi-threaded */

drivers/gpu/drm/i915/intel_dp.c

@@ -362,8 +362,8 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
 	 * clock divider.
 	 */
 	if (is_cpu_edp(intel_dp)) {
-		if (IS_GEN6(dev))
-			aux_clock_divider = 200; /* SNB eDP input clock at 400Mhz */
+		if (IS_GEN6(dev) || IS_GEN7(dev))
+			aux_clock_divider = 200; /* SNB & IVB eDP input clock at 400Mhz */
 		else
 			aux_clock_divider = 225; /* eDP input clock at 450Mhz */
 	} else if (HAS_PCH_SPLIT(dev))
@@ -817,10 +817,11 @@ intel_dp_mode_set(struct drm_encoder *encoder, struct drm_display_mode *mode,
 	}
 
 	/*
-	 * There are three kinds of DP registers:
+	 * There are four kinds of DP registers:
 	 *
 	 * 	IBX PCH
-	 * 	CPU
+	 * 	SNB CPU
+	 *	IVB CPU
 	 * 	CPT PCH
 	 *
 	 * IBX PCH and CPU are the same for almost everything,
@@ -873,7 +874,25 @@ intel_dp_mode_set(struct drm_encoder *encoder, struct drm_display_mode *mode,
 
 	/* Split out the IBX/CPU vs CPT settings */
 
-	if (!HAS_PCH_CPT(dev) || is_cpu_edp(intel_dp)) {
+	if (is_cpu_edp(intel_dp) && IS_GEN7(dev)) {
+		if (adjusted_mode->flags & DRM_MODE_FLAG_PHSYNC)
+			intel_dp->DP |= DP_SYNC_HS_HIGH;
+		if (adjusted_mode->flags & DRM_MODE_FLAG_PVSYNC)
+			intel_dp->DP |= DP_SYNC_VS_HIGH;
+		intel_dp->DP |= DP_LINK_TRAIN_OFF_CPT;
+
+		if (intel_dp->link_configuration[1] & DP_LANE_COUNT_ENHANCED_FRAME_EN)
+			intel_dp->DP |= DP_ENHANCED_FRAMING;
+
+		intel_dp->DP |= intel_crtc->pipe << 29;
+
+		/* don't miss out required setting for eDP */
+		intel_dp->DP |= DP_PLL_ENABLE;
+		if (adjusted_mode->clock < 200000)
+			intel_dp->DP |= DP_PLL_FREQ_160MHZ;
+		else
+			intel_dp->DP |= DP_PLL_FREQ_270MHZ;
+	} else if (!HAS_PCH_CPT(dev) || is_cpu_edp(intel_dp)) {
 		intel_dp->DP |= intel_dp->color_range;
 
 		if (adjusted_mode->flags & DRM_MODE_FLAG_PHSYNC)
@@ -1375,12 +1394,36 @@ static char	*link_train_names[] = {
  * These are source-specific values; current Intel hardware supports
  * a maximum voltage of 800mV and a maximum pre-emphasis of 6dB
  */
-#define I830_DP_VOLTAGE_MAX	    DP_TRAIN_VOLTAGE_SWING_800
-#define I830_DP_VOLTAGE_MAX_CPT	    DP_TRAIN_VOLTAGE_SWING_1200
 
 static uint8_t
-intel_dp_pre_emphasis_max(uint8_t voltage_swing)
+intel_dp_voltage_max(struct intel_dp *intel_dp)
+{
+	struct drm_device *dev = intel_dp->base.base.dev;
+
+	if (IS_GEN7(dev) && is_cpu_edp(intel_dp))
+		return DP_TRAIN_VOLTAGE_SWING_800;
+	else if (HAS_PCH_CPT(dev) && !is_cpu_edp(intel_dp))
+		return DP_TRAIN_VOLTAGE_SWING_1200;
+	else
+		return DP_TRAIN_VOLTAGE_SWING_800;
+}
+
+static uint8_t
+intel_dp_pre_emphasis_max(struct intel_dp *intel_dp, uint8_t voltage_swing)
 {
+	struct drm_device *dev = intel_dp->base.base.dev;
+
+	if (IS_GEN7(dev) && is_cpu_edp(intel_dp)) {
+		switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
+		case DP_TRAIN_VOLTAGE_SWING_400:
+			return DP_TRAIN_PRE_EMPHASIS_6;
+		case DP_TRAIN_VOLTAGE_SWING_600:
+		case DP_TRAIN_VOLTAGE_SWING_800:
+			return DP_TRAIN_PRE_EMPHASIS_3_5;
+		default:
+			return DP_TRAIN_PRE_EMPHASIS_0;
+		}
+	} else {
 		switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
 		case DP_TRAIN_VOLTAGE_SWING_400:
 			return DP_TRAIN_PRE_EMPHASIS_6;
@@ -1392,17 +1435,18 @@ intel_dp_pre_emphasis_max(uint8_t voltage_swing)
 		default:
 			return DP_TRAIN_PRE_EMPHASIS_0;
 		}
+	}
 }
 
 static void
 intel_get_adjust_train(struct intel_dp *intel_dp, uint8_t link_status[DP_LINK_STATUS_SIZE])
 {
-	struct drm_device *dev = intel_dp->base.base.dev;
 	uint8_t v = 0;
 	uint8_t p = 0;
 	int lane;
 	uint8_t	*adjust_request = link_status + (DP_ADJUST_REQUEST_LANE0_1 - DP_LANE0_1_STATUS);
-	int voltage_max;
+	uint8_t voltage_max;
+	uint8_t preemph_max;
 
 	for (lane = 0; lane < intel_dp->lane_count; lane++) {
 		uint8_t this_v = intel_get_adjust_request_voltage(adjust_request, lane);
@@ -1414,15 +1458,13 @@ intel_get_adjust_train(struct intel_dp *intel_dp, uint8_t link_status[DP_LINK_ST
 			p = this_p;
 	}
 
-	if (HAS_PCH_CPT(dev) && !is_cpu_edp(intel_dp))
-		voltage_max = I830_DP_VOLTAGE_MAX_CPT;
-	else
-		voltage_max = I830_DP_VOLTAGE_MAX;
+	voltage_max = intel_dp_voltage_max(intel_dp);
 	if (v >= voltage_max)
 		v = voltage_max | DP_TRAIN_MAX_SWING_REACHED;
 
-	if (p >= intel_dp_pre_emphasis_max(v))
-		p = intel_dp_pre_emphasis_max(v) | DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
+	preemph_max = intel_dp_pre_emphasis_max(intel_dp, v);
+	if (p >= preemph_max)
+		p = preemph_max | DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
 
 	for (lane = 0; lane < 4; lane++)
 		intel_dp->train_set[lane] = v | p;
@@ -1494,6 +1536,37 @@ intel_gen6_edp_signal_levels(uint8_t train_set)
 	}
 }
 
+/* Gen7's DP voltage swing and pre-emphasis control */
+static uint32_t
+intel_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_400 | DP_TRAIN_PRE_EMPHASIS_0:
+		return EDP_LINK_TRAIN_400MV_0DB_IVB;
+	case DP_TRAIN_VOLTAGE_SWING_400 | DP_TRAIN_PRE_EMPHASIS_3_5:
+		return EDP_LINK_TRAIN_400MV_3_5DB_IVB;
+	case DP_TRAIN_VOLTAGE_SWING_400 | DP_TRAIN_PRE_EMPHASIS_6:
+		return EDP_LINK_TRAIN_400MV_6DB_IVB;
+
+	case DP_TRAIN_VOLTAGE_SWING_600 | DP_TRAIN_PRE_EMPHASIS_0:
+		return EDP_LINK_TRAIN_600MV_0DB_IVB;
+	case DP_TRAIN_VOLTAGE_SWING_600 | DP_TRAIN_PRE_EMPHASIS_3_5:
+		return EDP_LINK_TRAIN_600MV_3_5DB_IVB;
+
+	case DP_TRAIN_VOLTAGE_SWING_800 | DP_TRAIN_PRE_EMPHASIS_0:
+		return EDP_LINK_TRAIN_800MV_0DB_IVB;
+	case DP_TRAIN_VOLTAGE_SWING_800 | DP_TRAIN_PRE_EMPHASIS_3_5:
+		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;
+	}
+}
+
 static uint8_t
 intel_get_lane_status(uint8_t link_status[DP_LINK_STATUS_SIZE],
 		      int lane)
@@ -1599,7 +1672,8 @@ intel_dp_start_link_train(struct intel_dp *intel_dp)
 				  DP_LINK_CONFIGURATION_SIZE);
 
 	DP |= DP_PORT_EN;
-	if (HAS_PCH_CPT(dev) && !is_cpu_edp(intel_dp))
+
+	if (HAS_PCH_CPT(dev) && (IS_GEN7(dev) || !is_cpu_edp(intel_dp)))
 		DP &= ~DP_LINK_TRAIN_MASK_CPT;
 	else
 		DP &= ~DP_LINK_TRAIN_MASK;
@@ -1613,7 +1687,11 @@ intel_dp_start_link_train(struct intel_dp *intel_dp)
 		uint8_t	    link_status[DP_LINK_STATUS_SIZE];
 		uint32_t    signal_levels;
 
-		if (IS_GEN6(dev) && is_cpu_edp(intel_dp)) {
+
+		if (IS_GEN7(dev) && is_cpu_edp(intel_dp)) {
+			signal_levels = intel_gen7_edp_signal_levels(intel_dp->train_set[0]);
+			DP = (DP & ~EDP_LINK_TRAIN_VOL_EMP_MASK_IVB) | signal_levels;
+		} else if (IS_GEN6(dev) && is_cpu_edp(intel_dp)) {
 			signal_levels = intel_gen6_edp_signal_levels(intel_dp->train_set[0]);
 			DP = (DP & ~EDP_LINK_TRAIN_VOL_EMP_MASK_SNB) | signal_levels;
 		} else {
@@ -1622,7 +1700,7 @@ intel_dp_start_link_train(struct intel_dp *intel_dp)
 			DP = (DP & ~(DP_VOLTAGE_MASK|DP_PRE_EMPHASIS_MASK)) | signal_levels;
 		}
 
-		if (HAS_PCH_CPT(dev) && !is_cpu_edp(intel_dp))
+		if (HAS_PCH_CPT(dev) && (IS_GEN7(dev) || !is_cpu_edp(intel_dp)))
 			reg = DP | DP_LINK_TRAIN_PAT_1_CPT;
 		else
 			reg = DP | DP_LINK_TRAIN_PAT_1;
@@ -1703,7 +1781,10 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp)
 			break;
 		}
 
-		if (IS_GEN6(dev) && is_cpu_edp(intel_dp)) {
+		if (IS_GEN7(dev) && is_cpu_edp(intel_dp)) {
+			signal_levels = intel_gen7_edp_signal_levels(intel_dp->train_set[0]);
+			DP = (DP & ~EDP_LINK_TRAIN_VOL_EMP_MASK_IVB) | signal_levels;
+		} else if (IS_GEN6(dev) && is_cpu_edp(intel_dp)) {
 			signal_levels = intel_gen6_edp_signal_levels(intel_dp->train_set[0]);
 			DP = (DP & ~EDP_LINK_TRAIN_VOL_EMP_MASK_SNB) | signal_levels;
 		} else {
@@ -1711,7 +1792,7 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp)
 			DP = (DP & ~(DP_VOLTAGE_MASK|DP_PRE_EMPHASIS_MASK)) | signal_levels;
 		}
 
-		if (HAS_PCH_CPT(dev) && !is_cpu_edp(intel_dp))
+		if (HAS_PCH_CPT(dev) && (IS_GEN7(dev) || !is_cpu_edp(intel_dp)))
 			reg = DP | DP_LINK_TRAIN_PAT_2_CPT;
 		else
 			reg = DP | DP_LINK_TRAIN_PAT_2;
@@ -1752,7 +1833,7 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp)
 		++tries;
 	}
 
-	if (HAS_PCH_CPT(dev) && !is_cpu_edp(intel_dp))
+	if (HAS_PCH_CPT(dev) && (IS_GEN7(dev) || !is_cpu_edp(intel_dp)))
 		reg = DP | DP_LINK_TRAIN_OFF_CPT;
 	else
 		reg = DP | DP_LINK_TRAIN_OFF;
@@ -1782,7 +1863,7 @@ intel_dp_link_down(struct intel_dp *intel_dp)
 		udelay(100);
 	}
 
-	if (HAS_PCH_CPT(dev) && !is_cpu_edp(intel_dp)) {
+	if (HAS_PCH_CPT(dev) && (IS_GEN7(dev) || !is_cpu_edp(intel_dp))) {
 		DP &= ~DP_LINK_TRAIN_MASK_CPT;
 		I915_WRITE(intel_dp->output_reg, DP | DP_LINK_TRAIN_PAT_IDLE_CPT);
 	} else {
@@ -1794,7 +1875,7 @@ intel_dp_link_down(struct intel_dp *intel_dp)
 	msleep(17);
 
 	if (is_edp(intel_dp)) {
-		if (HAS_PCH_CPT(dev) && !is_cpu_edp(intel_dp))
+		if (HAS_PCH_CPT(dev) && (IS_GEN7(dev) || !is_cpu_edp(intel_dp)))
 			DP |= DP_LINK_TRAIN_OFF_CPT;
 		else
 			DP |= DP_LINK_TRAIN_OFF;