1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index b6e4a762806b..eacbb2f9e091 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -698,6 +698,12 @@ static int i915_get_crtc_scanoutpos(struct drm_device *dev, int pipe,
         vbl_start = mode->crtc_vblank_start;
         vbl_end = mode->crtc_vblank_end;
 
+        if (mode->flags & DRM_MODE_FLAG_INTERLACE) {
+                vbl_start = DIV_ROUND_UP(vbl_start, 2);
+                vbl_end /= 2;
+                vtotal /= 2;
+        }
+
         ret |= DRM_SCANOUTPOS_VALID | DRM_SCANOUTPOS_ACCURATE;
 
         /*