drm/i915: Add eDP support on IGDNG mobile chip

This adds embedded DisplayPort support on next mobile chip which
aims to replace origin LVDS port. VBT's driver feature block has
been used to determine the type of current internal panel for eDP
or LVDS.

Currently no panel fitting support for eDP and backlight control
would be added in future.

Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

1 files changed, 105 insertions, 7 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 0715911cbd8..a6ff15ac548 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -40,6 +40,8 @@
 
 #define DP_LINK_CONFIGURATION_SIZE	9
 
+#define IS_eDP(i) ((i)->type == INTEL_OUTPUT_EDP)
+
 struct intel_dp_priv {
 	uint32_t output_reg;
 	uint32_t DP;
@@ -63,6 +65,19 @@ intel_dp_link_train(struct intel_output *intel_output, uint32_t DP,
 static void
 intel_dp_link_down(struct intel_output *intel_output, uint32_t DP);
 
+void
+intel_edp_link_config (struct intel_output *intel_output,
+		int *lane_num, int *link_bw)
+{
+	struct intel_dp_priv   *dp_priv = intel_output->dev_priv;
+
+	*lane_num = dp_priv->lane_count;
+	if (dp_priv->link_bw == DP_LINK_BW_1_62)
+		*link_bw = 162000;
+	else if (dp_priv->link_bw == DP_LINK_BW_2_7)
+		*link_bw = 270000;
+}
+
 static int
 intel_dp_max_lane_count(struct intel_output *intel_output)
 {
@@ -206,9 +221,10 @@ intel_dp_aux_ch(struct intel_output *intel_output,
 	 * and would like to run at 2MHz. So, take the
 	 * hrawclk value and divide by 2 and use that
 	 */
-	/* IGDNG: input clock fixed at 125Mhz, so aux_bit_clk always 62 */
-	if (IS_IGDNG(dev))
-		aux_clock_divider = 62;
+	if (IS_eDP(intel_output))
+		aux_clock_divider = 225; /* eDP input clock at 450Mhz */
+	else if (IS_IGDNG(dev))
+		aux_clock_divider = 62; /* IGDNG: input clock fixed at 125Mhz */
 	else
 		aux_clock_divider = intel_hrawclk(dev) / 2;
 
@@ -579,8 +595,38 @@ intel_dp_mode_set(struct drm_encoder *encoder, struct drm_display_mode *mode,
 
 	if (intel_crtc->pipe == 1)
 		dp_priv->DP |= DP_PIPEB_SELECT;
+
+	if (IS_eDP(intel_output)) {
+		/* don't miss out required setting for eDP */
+		dp_priv->DP |= DP_PLL_ENABLE;
+		if (adjusted_mode->clock < 200000)
+			dp_priv->DP |= DP_PLL_FREQ_160MHZ;
+		else
+			dp_priv->DP |= DP_PLL_FREQ_270MHZ;
+	}
 }
 
+static void igdng_edp_backlight_on (struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	u32 pp;
+
+	DRM_DEBUG("\n");
+	pp = I915_READ(PCH_PP_CONTROL);
+	pp |= EDP_BLC_ENABLE;
+	I915_WRITE(PCH_PP_CONTROL, pp);
+}
+
+static void igdng_edp_backlight_off (struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	u32 pp;
+
+	DRM_DEBUG("\n");
+	pp = I915_READ(PCH_PP_CONTROL);
+	pp &= ~EDP_BLC_ENABLE;
+	I915_WRITE(PCH_PP_CONTROL, pp);
+}
 
 static void
 intel_dp_dpms(struct drm_encoder *encoder, int mode)
@@ -592,11 +638,17 @@ intel_dp_dpms(struct drm_encoder *encoder, int mode)
 	uint32_t dp_reg = I915_READ(dp_priv->output_reg);
 
 	if (mode != DRM_MODE_DPMS_ON) {
-		if (dp_reg & DP_PORT_EN)
+		if (dp_reg & DP_PORT_EN) {
 			intel_dp_link_down(intel_output, dp_priv->DP);
+			if (IS_eDP(intel_output))
+				igdng_edp_backlight_off(dev);
+		}
 	} else {
-		if (!(dp_reg & DP_PORT_EN))
+		if (!(dp_reg & DP_PORT_EN)) {
 			intel_dp_link_train(intel_output, dp_priv->DP, dp_priv->link_configuration);
+			if (IS_eDP(intel_output))
+				igdng_edp_backlight_on(dev);
+		}
 	}
 	dp_priv->dpms_mode = mode;
 }
@@ -958,12 +1010,23 @@ intel_dp_link_down(struct intel_output *intel_output, uint32_t DP)
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_dp_priv *dp_priv = intel_output->dev_priv;
 
+	DRM_DEBUG("\n");
+
+	if (IS_eDP(intel_output)) {
+		DP &= ~DP_PLL_ENABLE;
+		I915_WRITE(dp_priv->output_reg, DP);
+		POSTING_READ(dp_priv->output_reg);
+		udelay(100);
+	}
+
 	DP &= ~DP_LINK_TRAIN_MASK;
 	I915_WRITE(dp_priv->output_reg, DP | DP_LINK_TRAIN_PAT_IDLE);
 	POSTING_READ(dp_priv->output_reg);
 
 	udelay(17000);
 
+	if (IS_eDP(intel_output))
+		DP |= DP_LINK_TRAIN_OFF;
 	I915_WRITE(dp_priv->output_reg, DP & ~DP_PORT_EN);
 	POSTING_READ(dp_priv->output_reg);
 }
@@ -1089,11 +1152,27 @@ intel_dp_detect(struct drm_connector *connector)
 static int intel_dp_get_modes(struct drm_connector *connector)
 {
 	struct intel_output *intel_output = to_intel_output(connector);
+	struct drm_device *dev = intel_output->base.dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	int ret;
 
 	/* We should parse the EDID data and find out if it has an audio sink
 	 */
 
-	return intel_ddc_get_modes(intel_output);
+	ret = intel_ddc_get_modes(intel_output);
+	if (ret)
+		return ret;
+
+	/* if eDP has no EDID, try to use fixed panel mode from VBT */
+	if (IS_eDP(intel_output)) {
+		if (dev_priv->panel_fixed_mode != NULL) {
+			struct drm_display_mode *mode;
+			mode = drm_mode_duplicate(dev, dev_priv->panel_fixed_mode);
+			drm_mode_probed_add(connector, mode);
+			return 1;
+		}
+	}
+	return 0;
 }
 
 static void
@@ -1170,7 +1249,10 @@ intel_dp_init(struct drm_device *dev, int output_reg)
 			   DRM_MODE_CONNECTOR_DisplayPort);
 	drm_connector_helper_add(connector, &intel_dp_connector_helper_funcs);
 
-	intel_output->type = INTEL_OUTPUT_DISPLAYPORT;
+	if (output_reg == DP_A)
+		intel_output->type = INTEL_OUTPUT_EDP;
+	else
+		intel_output->type = INTEL_OUTPUT_DISPLAYPORT;
 
 	connector->interlace_allowed = true;
 	connector->doublescan_allowed = 0;
@@ -1191,6 +1273,9 @@ intel_dp_init(struct drm_device *dev, int output_reg)
 
 	/* Set up the DDC bus. */
 	switch (output_reg) {
+		case DP_A:
+			name = "DPDDC-A";
+			break;
 		case DP_B:
 		case PCH_DP_B:
 			name = "DPDDC-B";
@@ -1206,9 +1291,22 @@ intel_dp_init(struct drm_device *dev, int output_reg)
 	}
 
 	intel_dp_i2c_init(intel_output, name);
+
 	intel_output->ddc_bus = &dp_priv->adapter;
 	intel_output->hot_plug = intel_dp_hot_plug;
 
+	if (output_reg == DP_A) {
+		/* initialize panel mode from VBT if available for eDP */
+		if (dev_priv->lfp_lvds_vbt_mode) {
+			dev_priv->panel_fixed_mode =
+				drm_mode_duplicate(dev, dev_priv->lfp_lvds_vbt_mode);
+			if (dev_priv->panel_fixed_mode) {
+				dev_priv->panel_fixed_mode->type |=
+					DRM_MODE_TYPE_PREFERRED;
+			}
+		}
+	}
+
 	/* For G4X desktop chip, PEG_BAND_GAP_DATA 3:0 must first be written
 	 * 0xd.  Failure to do so will result in spurious interrupts being
 	 * generated on the port when a cable is not attached.