diff --git a/src/include/nic.h b/src/include/nic.h
index 65e4be71..186b2ea4 100644
--- a/src/include/nic.h
+++ b/src/include/nic.h
@@ -17,6 +17,7 @@
 #include <gpxe/isa.h>
 #include <gpxe/eisa.h>
 #include <gpxe/mca.h>
+#include <gpxe/io.h>
 #include "dhcp.h"
 
 typedef enum {