diff --git a/sys/arm64/acpica/OsdEnvironment.c b/sys/arm64/acpica/OsdEnvironment.c
index 3d8afd0ab2d5..d1590bee7753 100644
--- a/sys/arm64/acpica/OsdEnvironment.c
+++ b/sys/arm64/acpica/OsdEnvironment.c
@@ -1,87 +1,88 @@
 /*-
  * Copyright (c) 2000,2001 Michael Smith
  * Copyright (c) 2000 BSDi
  * All rights reserved.
  *
  * 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.
  */
 
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
 #include <sys/types.h>
 #include <sys/bus.h>
+#include <sys/kernel.h>
 #include <sys/sysctl.h>
 
 #include <contrib/dev/acpica/include/acpi.h>
 #include <contrib/dev/acpica/include/aclocal.h>
 #include <contrib/dev/acpica/include/actables.h>
 
 static u_long acpi_root_phys;
 
 SYSCTL_ULONG(_machdep, OID_AUTO, acpi_root, CTLFLAG_RD, &acpi_root_phys, 0,
     "The physical address of the RSDP");
 
 ACPI_STATUS
 AcpiOsInitialize(void)
 {
 
 	return (AE_OK);
 }
 
 ACPI_STATUS
 AcpiOsTerminate(void)
 {
 
 	return (AE_OK);
 }
 
 static u_long
 acpi_get_root_from_loader(void)
 {
 	long acpi_root;
 
 	if (TUNABLE_ULONG_FETCH("acpi.rsdp", &acpi_root))
 		return (acpi_root);
 
 	/*
 	 * The hints mechanism is unreliable (it fails if anybody ever
 	 * compiled in hints to the kernel). It has been replaced
 	 * by the tunable method, but is used here as a fallback to
 	 * retain maximum compatibility between old loaders and new
 	 * kernels. It can be removed after 14.0R.
 	 */
 	if (resource_long_value("acpi", 0, "rsdp", &acpi_root) == 0)
 		return (acpi_root);
 
 	return (0);
 }
 
 ACPI_PHYSICAL_ADDRESS
 AcpiOsGetRootPointer(void)
 {
 
 	if (acpi_root_phys == 0)
 		acpi_root_phys = acpi_get_root_from_loader();
 
 	return (acpi_root_phys);
 }