xref: /freebsd/usr.sbin/acpi/acpidump/acpi_user.c (revision fa50a3552d1e759e1bb65e54cb0b7e863bcf54d5)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1999 Doug Rabson
5  * Copyright (c) 2000 Mitsuru IWASAKI <iwasaki@FreeBSD.org>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  *	$FreeBSD$
30  */
31 
32 #include <sys/param.h>
33 #include <sys/mman.h>
34 #include <sys/queue.h>
35 #include <sys/stat.h>
36 #include <sys/sysctl.h>
37 
38 #include <err.h>
39 #include <fcntl.h>
40 #include <kenv.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <unistd.h>
44 
45 #include "acpidump.h"
46 
47 static char	hint_acpi_0_rsdp[] = "hint.acpi.0.rsdp";
48 static char	machdep_acpi_root[] = "machdep.acpi_root";
49 static int      acpi_mem_fd = -1;
50 
51 struct acpi_user_mapping {
52 	LIST_ENTRY(acpi_user_mapping) link;
53 	vm_offset_t     pa;
54 	caddr_t         va;
55 	size_t          size;
56 };
57 
58 static LIST_HEAD(acpi_user_mapping_list, acpi_user_mapping) maplist;
59 
60 static void
61 acpi_user_init(void)
62 {
63 
64 	if (acpi_mem_fd == -1) {
65 		acpi_mem_fd = open("/dev/mem", O_RDONLY);
66 		if (acpi_mem_fd == -1)
67 			err(1, "opening /dev/mem");
68 		LIST_INIT(&maplist);
69 	}
70 }
71 
72 static struct acpi_user_mapping *
73 acpi_user_find_mapping(vm_offset_t pa, size_t size)
74 {
75 	struct	acpi_user_mapping *map;
76 
77 	/* First search for an existing mapping */
78 	for (map = LIST_FIRST(&maplist); map; map = LIST_NEXT(map, link)) {
79 		if (map->pa <= pa && map->size >= pa + size - map->pa)
80 			return (map);
81 	}
82 
83 	/* Then create a new one */
84 	size = round_page(pa + size) - trunc_page(pa);
85 	pa = trunc_page(pa);
86 	map = malloc(sizeof(struct acpi_user_mapping));
87 	if (!map)
88 		errx(1, "out of memory");
89 	map->pa = pa;
90 	map->va = mmap(0, size, PROT_READ, MAP_SHARED, acpi_mem_fd, pa);
91 	map->size = size;
92 	if ((intptr_t) map->va == -1)
93 		err(1, "can't map address");
94 	LIST_INSERT_HEAD(&maplist, map, link);
95 
96 	return (map);
97 }
98 
99 static ACPI_TABLE_RSDP *
100 acpi_get_rsdp(u_long addr)
101 {
102 	ACPI_TABLE_RSDP rsdp;
103 	size_t len;
104 
105 	/* Read in the table signature and check it. */
106 	pread(acpi_mem_fd, &rsdp, 8, addr);
107 	if (memcmp(rsdp.Signature, "RSD PTR ", 8))
108 		return (NULL);
109 
110 	/* Read the entire table. */
111 	pread(acpi_mem_fd, &rsdp, sizeof(rsdp), addr);
112 
113 	/* Check the standard checksum. */
114 	if (acpi_checksum(&rsdp, ACPI_RSDP_CHECKSUM_LENGTH) != 0)
115 		return (NULL);
116 
117 	/* Check extended checksum if table version >= 2. */
118 	if (rsdp.Revision >= 2 &&
119 	    acpi_checksum(&rsdp, ACPI_RSDP_XCHECKSUM_LENGTH) != 0)
120 		return (NULL);
121 
122 	/* If the revision is 0, assume a version 1 length. */
123 	if (rsdp.Revision == 0)
124 		len = sizeof(ACPI_RSDP_COMMON);
125 	else
126 		len = rsdp.Length;
127 
128 	return (acpi_map_physical(addr, len));
129 }
130 
131 static ACPI_TABLE_RSDP *
132 acpi_scan_rsd_ptr(void)
133 {
134 #if defined(__amd64__) || defined(__i386__)
135 	ACPI_TABLE_RSDP *rsdp;
136 	u_long		addr, end;
137 
138 	/*
139 	 * On ia32, scan physical memory for the RSD PTR if above failed.
140 	 * According to section 5.2.2 of the ACPI spec, we only consider
141 	 * two regions for the base address:
142 	 * 1. EBDA (1 KB area addressed by the 16 bit pointer at 0x40E
143 	 * 2. High memory (0xE0000 - 0xFFFFF)
144 	 */
145 	addr = ACPI_EBDA_PTR_LOCATION;
146 	pread(acpi_mem_fd, &addr, sizeof(uint16_t), addr);
147 	addr <<= 4;
148 	end = addr + ACPI_EBDA_WINDOW_SIZE;
149 	for (; addr < end; addr += 16)
150 		if ((rsdp = acpi_get_rsdp(addr)) != NULL)
151 			return (rsdp);
152 	addr = ACPI_HI_RSDP_WINDOW_BASE;
153 	end = addr + ACPI_HI_RSDP_WINDOW_SIZE;
154 	for (; addr < end; addr += 16)
155 		if ((rsdp = acpi_get_rsdp(addr)) != NULL)
156 			return (rsdp);
157 #endif /* __amd64__ || __i386__ */
158 	return (NULL);
159 }
160 
161 /*
162  * Public interfaces
163  */
164 ACPI_TABLE_RSDP *
165 acpi_find_rsd_ptr(void)
166 {
167 	ACPI_TABLE_RSDP *rsdp;
168 	char		buf[20];
169 	u_long		addr;
170 	size_t		len;
171 
172 	acpi_user_init();
173 
174 	addr = 0;
175 
176 	/* Attempt to use kenv or sysctl to find RSD PTR record. */
177 	if (kenv(KENV_GET, hint_acpi_0_rsdp, buf, 20) > 0)
178 		addr = strtoul(buf, NULL, 0);
179 	if (addr == 0) {
180 		len = sizeof(addr);
181 		if (sysctlbyname(machdep_acpi_root, &addr, &len, NULL, 0) != 0)
182 			addr = 0;
183 	}
184 	if (addr != 0 && (rsdp = acpi_get_rsdp(addr)) != NULL)
185 		return (rsdp);
186 
187 	return (acpi_scan_rsd_ptr());
188 }
189 
190 void *
191 acpi_map_physical(vm_offset_t pa, size_t size)
192 {
193 	struct	acpi_user_mapping *map;
194 
195 	map = acpi_user_find_mapping(pa, size);
196 	return (map->va + (pa - map->pa));
197 }
198 
199 ACPI_TABLE_HEADER *
200 dsdt_load_file(char *infile)
201 {
202 	ACPI_TABLE_HEADER *sdt;
203 	uint8_t		*dp;
204 	struct stat	 sb;
205 
206 	if ((acpi_mem_fd = open(infile, O_RDONLY)) == -1)
207 		errx(1, "opening %s", infile);
208 
209 	LIST_INIT(&maplist);
210 
211 	if (fstat(acpi_mem_fd, &sb) == -1)
212 		errx(1, "fstat %s", infile);
213 
214 	dp = mmap(0, sb.st_size, PROT_READ, MAP_PRIVATE, acpi_mem_fd, 0);
215 	if (dp == NULL)
216 		errx(1, "mmap %s", infile);
217 
218 	sdt = (ACPI_TABLE_HEADER *)dp;
219 	if (strncmp(dp, ACPI_SIG_DSDT, 4) != 0 ||
220 	    acpi_checksum(sdt, sdt->Length) != 0)
221 		return (NULL);
222 
223 	return (sdt);
224 }
225