drm/i915: fix Haswell FDI link disable path

This covers the "Disable FDI" section from the CRT mode set sequence.
This disables the FDI receiver and also the FDI pll.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_ddi.c

@@ -1365,6 +1365,32 @@ void intel_ddi_prepare_link_retrain(struct drm_encoder *encoder)
 	udelay(600);
 }
 
+void intel_ddi_fdi_disable(struct drm_crtc *crtc)
+{
+	struct drm_i915_private *dev_priv = crtc->dev->dev_private;
+	struct intel_encoder *intel_encoder = intel_ddi_get_crtc_encoder(crtc);
+	uint32_t val;
+
+	intel_ddi_post_disable(intel_encoder);
+
+	val = I915_READ(_FDI_RXA_CTL);
+	val &= ~FDI_RX_ENABLE;
+	I915_WRITE(_FDI_RXA_CTL, val);
+
+	val = I915_READ(_FDI_RXA_MISC);
+	val &= ~(FDI_RX_PWRDN_LANE1_MASK | FDI_RX_PWRDN_LANE0_MASK);
+	val |= FDI_RX_PWRDN_LANE1_VAL(2) | FDI_RX_PWRDN_LANE0_VAL(2);
+	I915_WRITE(_FDI_RXA_MISC, val);
+
+	val = I915_READ(_FDI_RXA_CTL);
+	val &= ~FDI_PCDCLK;
+	I915_WRITE(_FDI_RXA_CTL, val);
+
+	val = I915_READ(_FDI_RXA_CTL);
+	val &= ~FDI_RX_PLL_ENABLE;
+	I915_WRITE(_FDI_RXA_CTL, val);
+}
+
 static void intel_ddi_hot_plug(struct intel_encoder *intel_encoder)
 {
 	struct intel_dp *intel_dp = enc_to_intel_dp(&intel_encoder->base);

drivers/gpu/drm/i915/intel_display.c

@@ -3632,9 +3632,8 @@ static void haswell_crtc_disable(struct drm_crtc *crtc)
 			encoder->post_disable(encoder);
 
 	if (is_pch_port) {
-		ironlake_fdi_disable(crtc);
 		lpt_disable_pch_transcoder(dev_priv);
-		ironlake_fdi_pll_disable(intel_crtc);
+		intel_ddi_fdi_disable(crtc);
 	}
 
 	intel_crtc->active = false;

drivers/gpu/drm/i915/intel_drv.h

@@ -662,6 +662,8 @@ extern bool intel_ddi_pll_mode_set(struct drm_crtc *crtc, int clock);
 extern void intel_ddi_put_crtc_pll(struct drm_crtc *crtc);
 extern void intel_ddi_set_pipe_settings(struct drm_crtc *crtc);
 extern void intel_ddi_prepare_link_retrain(struct drm_encoder *encoder);
-bool intel_ddi_connector_get_hw_state(struct intel_connector *intel_connector);
+extern bool
+intel_ddi_connector_get_hw_state(struct intel_connector *intel_connector);
+extern void intel_ddi_fdi_disable(struct drm_crtc *crtc);
 
 #endif /* __INTEL_DRV_H__ */