FDI_FE_ERRC_ENABLE);
 }
 
-static bool pipe_has_enabled_pch(struct intel_crtc *crtc)
-{
-       return crtc->base.state->enable && crtc->active &&
-               crtc->config->has_pch_encoder;
-}
-
 /* The FDI link training functions for ILK/Ibexpeak. */
 static void ironlake_fdi_link_train(struct drm_crtc *crtc)
 {
        return encoder->get_hw_state(encoder, &pipe);
 }
 
+static int pipe_required_fdi_lanes(struct drm_device *dev, enum pipe pipe)
+{
+       struct intel_crtc *crtc =
+               to_intel_crtc(intel_get_crtc_for_pipe(dev, pipe));
+
+       if (crtc->base.state->enable &&
+           crtc->config->has_pch_encoder)
+               return crtc->config->fdi_lanes;
+
+       return 0;
+}
+
 static bool ironlake_check_fdi_lanes(struct drm_device *dev, enum pipe pipe,
                                     struct intel_crtc_state *pipe_config)
 {
-       struct drm_i915_private *dev_priv = dev->dev_private;
-       struct intel_crtc *pipe_B_crtc =
-               to_intel_crtc(dev_priv->pipe_to_crtc_mapping[PIPE_B]);
-
        DRM_DEBUG_KMS("checking fdi config on pipe %c, lanes %i\n",
                      pipe_name(pipe), pipe_config->fdi_lanes);
        if (pipe_config->fdi_lanes > 4) {
        case PIPE_A:
                return true;
        case PIPE_B:
-               if (dev_priv->pipe_to_crtc_mapping[PIPE_C]->enabled &&
-                   pipe_config->fdi_lanes > 2) {
+               if (pipe_config->fdi_lanes > 2 &&
+                   pipe_required_fdi_lanes(dev, PIPE_C) > 0) {
                        DRM_DEBUG_KMS("invalid shared fdi lane config on pipe %c: %i lanes\n",
                                      pipe_name(pipe), pipe_config->fdi_lanes);
                        return false;
                                      pipe_name(pipe), pipe_config->fdi_lanes);
                        return false;
                }
-               if (pipe_has_enabled_pch(pipe_B_crtc) &&
-                   pipe_B_crtc->config->fdi_lanes > 2) {
+               if (pipe_required_fdi_lanes(dev, PIPE_B) > 2) {
                        DRM_DEBUG_KMS("fdi link B uses too many lanes to enable link C\n");
                        return false;
                }