diff --git a/hw/sh4/r2d.c b/hw/sh4/r2d.c
index 7eecd79fcc..e6cc156c23 100644
--- a/hw/sh4/r2d.c
+++ b/hw/sh4/r2d.c
@@ -43,6 +43,7 @@
 #include "hw/loader.h"
 #include "hw/usb.h"
 #include "hw/block/flash.h"
+#include "exec/tswap.h"
 
 #define FLASH_BASE 0x00000000
 #define FLASH_SIZE (16 * MiB)