xref: /freebsd/sys/arm64/acpica/OsdEnvironment.c (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a)
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/types.h>
29 #include <sys/bus.h>
30 #include <sys/kernel.h>
31 #include <sys/sysctl.h>
32 
33 #include <contrib/dev/acpica/include/acpi.h>
34 #include <contrib/dev/acpica/include/aclocal.h>
35 #include <contrib/dev/acpica/include/actables.h>
36 
37 static u_long acpi_root_phys;
38 
39 SYSCTL_ULONG(_machdep, OID_AUTO, acpi_root, CTLFLAG_RD, &acpi_root_phys, 0,
40     "The physical address of the RSDP");
41 
42 ACPI_STATUS
43 AcpiOsInitialize(void)
44 {
45 
46 	return (AE_OK);
47 }
48 
49 ACPI_STATUS
50 AcpiOsTerminate(void)
51 {
52 
53 	return (AE_OK);
54 }
55 
56 static u_long
57 acpi_get_root_from_loader(void)
58 {
59 	long acpi_root;
60 
61 	if (TUNABLE_ULONG_FETCH("acpi.rsdp", &acpi_root))
62 		return (acpi_root);
63 
64 	/*
65 	 * The hints mechanism is considered legacy and has been replaced
66 	 * by the tunable method, but is used here as a fallback to
67 	 * retain maximum compatibility between old loaders and new
68 	 * kernels. It can be removed after 14.0R.
69 	 */
70 	if (resource_long_value("acpi", 0, "rsdp", &acpi_root) == 0)
71 		return (acpi_root);
72 
73 	return (0);
74 }
75 
76 ACPI_PHYSICAL_ADDRESS
77 AcpiOsGetRootPointer(void)
78 {
79 
80 	if (acpi_root_phys == 0)
81 		acpi_root_phys = acpi_get_root_from_loader();
82 
83 	return (acpi_root_phys);
84 }
85