diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 3283669..52a234c 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -451,7 +451,7 @@
 				     const struct drm_display_mode *mode)
 {
 	s64 linedur_ns = 0, pixeldur_ns = 0, framedur_ns = 0;
-	int dotclock = mode->clock;
+	int dotclock = mode->crtc_clock;
 
 	/* Fields of interlaced scanout modes are only half a frame duration.
 	 * Double the dotclock to get half the frame-/line-/pixelduration.