diff --git a/sys/dev/drm/amd/display/modules/freesync/freesync.c b/sys/dev/drm/amd/display/modules/freesync/freesync.c
--- a/sys/dev/drm/amd/display/modules/freesync/freesync.c
+++ b/sys/dev/drm/amd/display/modules/freesync/freesync.c
@@ -93,7 +93,12 @@
 static unsigned int calc_duration_in_us_from_refresh_in_uhz(
 		unsigned int refresh_in_uhz)
 {
-	unsigned int duration_in_us =
+	unsigned int duration_in_us;
+
+	if (refresh_in_uhz == 0)
+		return 0;
+
+	duration_in_us =
 			((unsigned int)(div64_u64((1000000000ULL * 1000),
 					refresh_in_uhz)));
 	return duration_in_us;