diff --git a/sys/arm64/include/ifunc.h b/sys/arm64/include/ifunc.h
index de452ad34c8f..34e783df8fe5 100644
--- a/sys/arm64/include/ifunc.h
+++ b/sys/arm64/include/ifunc.h
@@ -1,48 +1,66 @@
 /*-
  * Copyright (c) 2015-2018 The FreeBSD Foundation
  *
  * This software was developed by Konstantin Belousov <kib@FreeBSD.org>
  * under sponsorship from the FreeBSD Foundation.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
 
 #ifndef __ARM64_IFUNC_H
 #define	__ARM64_IFUNC_H
 
+struct __ifunc_arg_t
+{
+	unsigned long _size; /* Size of the struct, so it can grow. */
+	unsigned long _hwcap;
+	unsigned long _hwcap2;
+	unsigned long _hwcap3;
+	unsigned long _hwcap4;
+};
+
+typedef struct __ifunc_arg_t __ifunc_arg_t;
+
+#define _IFUNC_ARG_HWCAP (1ULL << 62)
+
 #define	DEFINE_IFUNC(qual, ret_type, name, args)			\
     static ret_type (*name##_resolver(void))args __used;		\
     qual ret_type name args __attribute__((ifunc(#name "_resolver")));	\
     static ret_type (*name##_resolver(void))args
 
 #define	DEFINE_UIFUNC(qual, ret_type, name, args)			\
-    static ret_type (*name##_resolver(uint64_t, uint64_t,		\
+    static ret_type (*name##_resolver(uint64_t,				\
+	const struct __ifunc_arg_t *ifunc_arg,				\
 	uint64_t, uint64_t, uint64_t, uint64_t, uint64_t,		\
 	uint64_t))args __used;						\
     qual ret_type name args __attribute__((ifunc(#name "_resolver")));	\
-    static ret_type (*name##_resolver(uint64_t _arg1 __unused,		\
-	uint64_t _arg2 __unused, uint64_t _arg3 __unused,		\
-	uint64_t _arg4 __unused, uint64_t _arg5 __unused,		\
-	uint64_t _arg6 __unused, uint64_t _arg7 __unused,		\
+    static ret_type (*name##_resolver(					\
+	uint64_t at_hwcap __unused,					\
+	const struct __ifunc_arg_t *ifunc_arg __unused,			\
+	uint64_t _arg3 __unused,					\
+	uint64_t _arg4 __unused,					\
+	uint64_t _arg5 __unused,					\
+	uint64_t _arg6 __unused,					\
+	uint64_t _arg7 __unused,					\
 	uint64_t _arg8 __unused))args
 
 #endif