diff --git a/include/common/debug.h b/include/common/debug.h
index 646daba..814cf84 100644
--- a/include/common/debug.h
+++ b/include/common/debug.h
@@ -64,6 +64,7 @@
 void __dead2 __stack_chk_fail(void);
 
 void tf_printf(const char *fmt, ...) __printflike(1, 2);
+int tf_snprintf(char *s, size_t n, const char *fmt, ...) __printflike(3, 4);
 
 #endif /* __ASSEMBLY__ */
 #endif /* __DEBUG_H__ */