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  * $FreeBSD: src/sys/i386/acpica/OsdEnvironment.c,v 1.10 2004/05/06 02:18:58 njl Exp $
28  */
29 
30 /*
31  * Environmental and ACPI Tables (partial)
32  */
33 
34 #include <sys/types.h>
35 #include <sys/linker_set.h>
36 #include <sys/sysctl.h>
37 
38 #include <machine/vmparam.h>
39 
40 #include "acpi.h"
41 
42 static u_long acpi_root_phys;
43 
44 SYSCTL_ULONG(_machdep, OID_AUTO, acpi_root, CTLFLAG_RD, &acpi_root_phys, 0,
45     "The physical address of the RSDP");
46 
47 ACPI_STATUS
48 AcpiOsInitialize(void)
49 {
50 	return (AE_OK);
51 }
52 
53 ACPI_STATUS
54 AcpiOsTerminate(void)
55 {
56 	return (AE_OK);
57 }
58 
59 ACPI_PHYSICAL_ADDRESS
60 AcpiOsGetRootPointer(void)
61 {
62 	ACPI_SIZE ptr;
63 	ACPI_STATUS status;
64 	u_long acpi_root;
65 
66 	if (acpi_root_phys == 0) {
67 		/*
68 		 * The loader passes the physical address at which it found the
69 		 * RSDP in a hint.  We try to recover this before searching
70 		 * manually here.
71 		 */
72 		if (kgetenv_ulong("hint.acpi.0.rsdp", &acpi_root) == 1) {
73 			acpi_root_phys = acpi_root;
74 		} else {
75 			status = AcpiFindRootPointer(&ptr);
76 			if (ACPI_SUCCESS(status))
77 				acpi_root_phys = ptr;
78 		}
79 	}
80 
81 	return (acpi_root_phys);
82 }
83