2 * Copyright (c) 2000,2001 Michael Smith
3 * Copyright (c) 2000 BSDi
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
31 #include <sys/types.h>
33 #include <sys/kernel.h>
34 #include <sys/sysctl.h>
36 #include <contrib/dev/acpica/include/acpi.h>
37 #include <contrib/dev/acpica/include/aclocal.h>
38 #include <contrib/dev/acpica/include/actables.h>
40 static u_long acpi_root_phys;
42 SYSCTL_ULONG(_machdep, OID_AUTO, acpi_root, CTLFLAG_RD, &acpi_root_phys, 0,
43 "The physical address of the RSDP");
46 AcpiOsInitialize(void)
60 acpi_get_root_from_loader(void)
64 if (TUNABLE_ULONG_FETCH("acpi.rsdp", &acpi_root))
68 * The hints mechanism is unreliable (it fails if anybody ever
69 * compiled in hints to the kernel). It has been replaced
70 * by the tunable method, but is used here as a fallback to
71 * retain maximum compatibility between old loaders and new
72 * kernels. It can be removed after 11.0R.
74 if (resource_long_value("acpi", 0, "rsdp", &acpi_root) == 0)
81 acpi_get_root_from_memory(void)
83 ACPI_PHYSICAL_ADDRESS acpi_root;
85 if (ACPI_SUCCESS(AcpiFindRootPointer(&acpi_root)))
92 AcpiOsGetRootPointer(void)
95 if (acpi_root_phys == 0) {
96 acpi_root_phys = acpi_get_root_from_loader();
97 if (acpi_root_phys == 0)
98 acpi_root_phys = acpi_get_root_from_memory();
101 return (acpi_root_phys);