1/*-
2 * Copyright (c) 2000,2001 Michael Smith
3 * Copyright (c) 2000 BSDi
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
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.
14 *
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
25 * SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD: stable/11/sys/x86/acpica/OsdEnvironment.c 316303 2017-03-30 20:18:34Z jkim $");
30
31#include <sys/types.h>
32#include <sys/bus.h>
33#include <sys/kernel.h>
34#include <sys/sysctl.h>
35
36#include <contrib/dev/acpica/include/acpi.h>
37#include <contrib/dev/acpica/include/aclocal.h>
38#include <contrib/dev/acpica/include/actables.h>
39
40static u_long acpi_root_phys;
41
42SYSCTL_ULONG(_machdep, OID_AUTO, acpi_root, CTLFLAG_RD, &acpi_root_phys, 0,
43    "The physical address of the RSDP");
44
45ACPI_STATUS
46AcpiOsInitialize(void)
47{
48
49	return (AE_OK);
50}
51
52ACPI_STATUS
53AcpiOsTerminate(void)
54{
55
56	return (AE_OK);
57}
58
59static u_long
60acpi_get_root_from_loader(void)
61{
62	long acpi_root;
63
64	if (TUNABLE_ULONG_FETCH("acpi.rsdp", &acpi_root))
65		return (acpi_root);
66
67	/*
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.
73	 */
74	if (resource_long_value("acpi", 0, "rsdp", &acpi_root) == 0)
75		return (acpi_root);
76
77	return (0);
78}
79
80static u_long
81acpi_get_root_from_memory(void)
82{
83	ACPI_PHYSICAL_ADDRESS acpi_root;
84
85	if (ACPI_SUCCESS(AcpiFindRootPointer(&acpi_root)))
86		return (acpi_root);
87
88	return (0);
89}
90
91ACPI_PHYSICAL_ADDRESS
92AcpiOsGetRootPointer(void)
93{
94
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();
99	}
100
101	return (acpi_root_phys);
102}
103