diff --git a/include/u-boot/rsa-mod-exp.h b/include/u-boot/rsa-mod-exp.h
index 7b7c2915a9..fc9557c781 100644
--- a/include/u-boot/rsa-mod-exp.h
+++ b/include/u-boot/rsa-mod-exp.h
@@ -9,6 +9,8 @@
 #include <errno.h>
 #include <image.h>
 
+struct udevice;
+
 /**
  * struct key_prop - holder for a public key properties
  *