diff --git a/arch/powerpc/platforms/powernv/opal-call.c b/arch/powerpc/platforms/powernv/opal-call.c
index daad8c45c8e729d53cf83c3a5011024be178affa..c53773a149e0669489bef48019e7ccee71e6cd12 100644
--- a/arch/powerpc/platforms/powernv/opal-call.c
+++ b/arch/powerpc/platforms/powernv/opal-call.c
@@ -120,6 +120,8 @@ static int64_t opal_call(int64_t a0, int64_t a1, int64_t a2, int64_t a3,
 }
 
 #define OPAL_CALL(name, opcode)					\
+int64_t name(int64_t a0, int64_t a1, int64_t a2, int64_t a3,	\
+	     int64_t a4, int64_t a5, int64_t a6, int64_t a7);	\
 int64_t name(int64_t a0, int64_t a1, int64_t a2, int64_t a3,	\
 	     int64_t a4, int64_t a5, int64_t a6, int64_t a7)	\
 {								\