diff --git a/ipl/pdc_misc.c b/ipl/pdc_misc.c
index f516bd8..60f0d92 100644
--- a/ipl/pdc_misc.c
+++ b/ipl/pdc_misc.c
@@ -95,7 +95,7 @@ firmware_call(unsigned long long fn, ...)
     }
     else
     {
-	typedef int (*firmware_entry)();
+	typedef int (*firmware_entry)(unsigned long arg0, ...);
 	unsigned long arg0, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8,
 	    arg9, arg10, arg11, arg12, arg13;
 
