diff --git a/chip/ish/uart.c b/chip/ish/uart.c
index cd05aee329..96a55f94c7 100644
--- a/chip/ish/uart.c
+++ b/chip/ish/uart.c
@@ -13,6 +13,7 @@
 #include "uart.h"
 #include "uart_defs.h"
 #include "interrupts.h"
+#include "system.h"
 
 #define CPUTS(outstr) cputs(CC_LPC, outstr)
 #define CPRINTS(format, args...) cprints(CC_LPC, format, ## args)