xref: /freebsd/sys/arm64/acpica/OsdEnvironment.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
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 #include <sys/types.h>
30 #include <sys/bus.h>
31 #include <sys/kernel.h>
32 #include <sys/sysctl.h>
33 
34 #include <contrib/dev/acpica/include/acpi.h>
35 #include <contrib/dev/acpica/include/aclocal.h>
36 #include <contrib/dev/acpica/include/actables.h>
37 
38 static u_long acpi_root_phys;
39 
40 SYSCTL_ULONG(_machdep, OID_AUTO, acpi_root, CTLFLAG_RD, &acpi_root_phys, 0,
41     "The physical address of the RSDP");
42 
43 ACPI_STATUS
44 AcpiOsInitialize(void)
45 {
46 
47 	return (AE_OK);
48 }
49 
50 ACPI_STATUS
51 AcpiOsTerminate(void)
52 {
53 
54 	return (AE_OK);
55 }
56 
57 static u_long
58 acpi_get_root_from_loader(void)
59 {
60 	long acpi_root;
61 
62 	if (TUNABLE_ULONG_FETCH("acpi.rsdp", &acpi_root))
63 		return (acpi_root);
64 
65 	/*
66 	 * The hints mechanism is considered legacy and has been replaced
67 	 * by the tunable method, but is used here as a fallback to
68 	 * retain maximum compatibility between old loaders and new
69 	 * kernels. It can be removed after 14.0R.
70 	 */
71 	if (resource_long_value("acpi", 0, "rsdp", &acpi_root) == 0)
72 		return (acpi_root);
73 
74 	return (0);
75 }
76 
77 ACPI_PHYSICAL_ADDRESS
78 AcpiOsGetRootPointer(void)
79 {
80 
81 	if (acpi_root_phys == 0)
82 		acpi_root_phys = acpi_get_root_from_loader();
83 
84 	return (acpi_root_phys);
85 }
86