diff --git a/sys/dev/cxgbe/common/t4_hw.c b/sys/dev/cxgbe/common/t4_hw.c
index c603c7144d02..2312b66cf7a8 100644
--- a/sys/dev/cxgbe/common/t4_hw.c
+++ b/sys/dev/cxgbe/common/t4_hw.c
@@ -5770,7 +5770,7 @@ int t4_set_sched_ipg(struct adapter *adap, int sched, unsigned int ipg)
  */
 static u64 chan_rate(struct adapter *adap, unsigned int bytes256)
 {
-	u64 v = bytes256 * adap->params.vpd.cclk;
+	u64 v = (u64)bytes256 * adap->params.vpd.cclk;
 
 	return v * 62 + v / 2;
 }