diff --git a/src/northbridge/intel/x4x/x4x.h b/src/northbridge/intel/x4x/x4x.h
index 05479a1602..76d94c6c17 100644
--- a/src/northbridge/intel/x4x/x4x.h
+++ b/src/northbridge/intel/x4x/x4x.h
@@ -18,6 +18,8 @@
 #ifndef __NORTHBRIDGE_INTEL_X4X_H__
 #define __NORTHBRIDGE_INTEL_X4X_H__
 
+#include "iomap.h"
+
 /*
  * D0:F0
  */