acpi_user.c revision 129230 
1/*-
2 * Copyright (c) 1999 Doug Rabson
3 * Copyright (c) 2000 Mitsuru IWASAKI <iwasaki@FreeBSD.org>
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: head/usr.sbin/acpi/acpidump/acpi_user.c 129230 2004-05-14 16:52:39Z njl $
28 */
29
30#include <sys/param.h>
31#include <sys/mman.h>
32#include <sys/queue.h>
33#include <sys/stat.h>
34#include <sys/sysctl.h>
35
36#include <err.h>
37#include <fcntl.h>
38#include <stdlib.h>
39#include <string.h>
40#include <unistd.h>
41
42#include "acpidump.h"
43
44static char	machdep_acpi_root[] = "machdep.acpi_root";
45static int      acpi_mem_fd = -1;
46
47struct acpi_user_mapping {
48	LIST_ENTRY(acpi_user_mapping) link;
49	vm_offset_t     pa;
50	caddr_t         va;
51	size_t          size;
52};
53
54LIST_HEAD(acpi_user_mapping_list, acpi_user_mapping) maplist;
55
56static void
57acpi_user_init(void)
58{
59
60	if (acpi_mem_fd == -1) {
61		acpi_mem_fd = open("/dev/mem", O_RDONLY);
62		if (acpi_mem_fd == -1)
63			err(1, "opening /dev/mem");
64		LIST_INIT(&maplist);
65	}
66}
67
68static struct acpi_user_mapping *
69acpi_user_find_mapping(vm_offset_t pa, size_t size)
70{
71	struct	acpi_user_mapping *map;
72
73	/* First search for an existing mapping */
74	for (map = LIST_FIRST(&maplist); map; map = LIST_NEXT(map, link)) {
75		if (map->pa <= pa && map->size >= pa + size - map->pa)
76			return (map);
77	}
78
79	/* Then create a new one */
80	size = round_page(pa + size) - trunc_page(pa);
81	pa = trunc_page(pa);
82	map = malloc(sizeof(struct acpi_user_mapping));
83	if (!map)
84		errx(1, "out of memory");
85	map->pa = pa;
86	map->va = mmap(0, size, PROT_READ, MAP_SHARED, acpi_mem_fd, pa);
87	map->size = size;
88	if ((intptr_t) map->va == -1)
89		err(1, "can't map address");
90	LIST_INSERT_HEAD(&maplist, map, link);
91
92	return (map);
93}
94
95static struct ACPIrsdp *
96acpi_get_rsdp(u_long addr)
97{
98	struct ACPIrsdp rsdp;
99	size_t		len;
100
101	pread(acpi_mem_fd, &rsdp, 8, addr);
102	if (memcmp(rsdp.signature, "RSD PTR ", 8))
103		return (NULL);
104	/* Read the entire table. */
105	len = sizeof(rsdp);
106	pread(acpi_mem_fd, &rsdp, len, addr);
107	if (acpi_checksum(&rsdp, len))
108		return (NULL);
109	if (rsdp.revision > 0)
110		len = rsdp.length;
111	return (acpi_map_physical(addr, len));
112}
113
114/*
115 * Public interfaces
116 */
117struct ACPIrsdp *
118acpi_find_rsd_ptr(void)
119{
120	struct ACPIrsdp *rsdp;
121	u_long		addr;
122	size_t		len;
123
124	acpi_user_init();
125
126	/* Attempt to use sysctl to find RSD PTR record. */
127	len = sizeof(addr);
128	if (sysctlbyname(machdep_acpi_root, &addr, &len, NULL, 0) == 0) {
129		if ((rsdp = acpi_get_rsdp(addr)) != NULL)
130			return (rsdp);
131		else
132			warnx("sysctl %s does not point to RSDP",
133			    machdep_acpi_root);
134	}
135
136#if defined(__i386__)
137	/*
138	 * On ia32, scan physical memory for the RSD PTR if above failed.
139	 * According to section 5.2.2 of the ACPI spec, we only consider
140	 * two regions for the base address:
141	 * 1. EBDA (0x0 - 0x3FF)
142	 * 2. High memory (0xE0000 - 0xFFFFF)
143	 */
144	for (addr = RSDP_EBDA_START; addr < RSDP_EBDA_END; addr += 16)
145		if ((rsdp = acpi_get_rsdp(addr)) != NULL)
146			return (rsdp);
147	for (addr = RSDP_HI_START; addr < RSDP_HI_END; addr += 16)
148		if ((rsdp = acpi_get_rsdp(addr)) != NULL)
149			return (rsdp);
150#endif
151
152	return (NULL);
153}
154
155void *
156acpi_map_physical(vm_offset_t pa, size_t size)
157{
158	struct	acpi_user_mapping *map;
159
160	map = acpi_user_find_mapping(pa, size);
161	return (map->va + (pa - map->pa));
162}
163
164struct ACPIsdt *
165dsdt_load_file(char *infile)
166{
167	struct ACPIsdt	*sdt;
168	uint8_t		*dp;
169	struct stat	 sb;
170
171	if ((acpi_mem_fd = open(infile, O_RDONLY)) == -1)
172		errx(1, "opening %s", infile);
173
174	LIST_INIT(&maplist);
175
176	if (fstat(acpi_mem_fd, &sb) == -1)
177		errx(1, "fstat %s", infile);
178
179	dp = mmap(0, sb.st_size, PROT_READ, MAP_PRIVATE, acpi_mem_fd, 0);
180	if (dp == NULL)
181		errx(1, "mmap %s", infile);
182
183	sdt = (struct ACPIsdt *)dp;
184	if (strncmp(dp, "DSDT", 4) != 0 || acpi_checksum(sdt, sdt->len) != 0)
185		return (NULL);
186
187	return (sdt);
188}
189