diff --git a/sys/powerpc/powerpc/suswintr.c b/sys/powerpc/powerpc/suswintr.c
index 949a0ade6e5..0252201e8a4 100644
--- a/sys/powerpc/powerpc/suswintr.c
+++ b/sys/powerpc/powerpc/suswintr.c
@@ -35,6 +35,7 @@
 __FBSDID("$FreeBSD$");
 
 #include <sys/param.h>
+#include <sys/systm.h>
 #include <sys/resourcevar.h>
 
 /*