diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
index e16ac5a28c3cb178550f4f1763ea81fdd25d801e..d5c130202396bff52d96b877abd0b1f8a77cd767 100644
--- a/drivers/gpu/drm/i915/intel_crt.c
+++ b/drivers/gpu/drm/i915/intel_crt.c
@@ -569,7 +569,7 @@ void intel_crt_init(struct drm_device *dev)
 				   (1 << INTEL_ANALOG_CLONE_BIT) |
 				   (1 << INTEL_SDVO_LVDS_CLONE_BIT);
 	intel_encoder->crtc_mask = (1 << 0) | (1 << 1);
-	connector->interlace_allowed = 0;
+	connector->interlace_allowed = 1;
 	connector->doublescan_allowed = 0;
 
 	drm_encoder_helper_add(&intel_encoder->enc, &intel_crt_helper_funcs);
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 36afe94099640fe56abce08b6cb38c7bfa457fab..4c7c151114f7515a201481e908951c67493c1bc1 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2354,6 +2354,8 @@ static bool intel_crtc_mode_fixup(struct drm_crtc *crtc,
 		if (mode->clock * 3 > 27000 * 4)
 			return MODE_CLOCK_HIGH;
 	}
+
+	drm_mode_set_crtcinfo(adjusted_mode, 0);
 	return true;
 }
 
@@ -3781,6 +3783,18 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
 		}
 	}
 
+	if (adjusted_mode->flags & DRM_MODE_FLAG_INTERLACE) {
+		pipeconf |= PIPECONF_INTERLACE_W_FIELD_INDICATION;
+		/* the chip adds 2 halflines automatically */
+		adjusted_mode->crtc_vdisplay -= 1;
+		adjusted_mode->crtc_vtotal -= 1;
+		adjusted_mode->crtc_vblank_start -= 1;
+		adjusted_mode->crtc_vblank_end -= 1;
+		adjusted_mode->crtc_vsync_end -= 1;
+		adjusted_mode->crtc_vsync_start -= 1;
+	} else
+		pipeconf &= ~PIPECONF_INTERLACE_W_FIELD_INDICATION; /* progressive */
+
 	I915_WRITE(htot_reg, (adjusted_mode->crtc_hdisplay - 1) |
 		   ((adjusted_mode->crtc_htotal - 1) << 16));
 	I915_WRITE(hblank_reg, (adjusted_mode->crtc_hblank_start - 1) |