1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
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
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 <kenv.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <unistd.h>
42
43 #include "acpidump.h"
44
45 static char hint_acpi_0_rsdp[] = "hint.acpi.0.rsdp";
46 static char machdep_acpi_root[] = "machdep.acpi_root";
47 static int acpi_mem_fd = -1;
48
49 struct acpi_user_mapping {
50 LIST_ENTRY(acpi_user_mapping) link;
51 vm_offset_t pa;
52 caddr_t va;
53 size_t size;
54 };
55
56 static LIST_HEAD(acpi_user_mapping_list, acpi_user_mapping) maplist;
57
58 static void
acpi_user_init(void)59 acpi_user_init(void)
60 {
61
62 if (acpi_mem_fd == -1) {
63 acpi_mem_fd = open("/dev/mem", O_RDONLY);
64 if (acpi_mem_fd == -1)
65 err(1, "opening /dev/mem");
66 LIST_INIT(&maplist);
67 }
68 }
69
70 static struct acpi_user_mapping *
acpi_user_find_mapping(vm_offset_t pa,size_t size)71 acpi_user_find_mapping(vm_offset_t pa, size_t size)
72 {
73 struct acpi_user_mapping *map;
74
75 /* First search for an existing mapping */
76 for (map = LIST_FIRST(&maplist); map; map = LIST_NEXT(map, link)) {
77 if (map->pa <= pa && map->size >= pa + size - map->pa)
78 return (map);
79 }
80
81 /* Then create a new one */
82 size = round_page(pa + size) - trunc_page(pa);
83 pa = trunc_page(pa);
84 map = malloc(sizeof(struct acpi_user_mapping));
85 if (!map)
86 errx(1, "out of memory");
87 map->pa = pa;
88 map->va = mmap(0, size, PROT_READ, MAP_SHARED, acpi_mem_fd, pa);
89 map->size = size;
90 if ((intptr_t) map->va == -1)
91 err(1, "can't map address");
92 LIST_INSERT_HEAD(&maplist, map, link);
93
94 return (map);
95 }
96
97 static ACPI_TABLE_RSDP *
acpi_get_rsdp(u_long addr)98 acpi_get_rsdp(u_long addr)
99 {
100 ACPI_TABLE_RSDP rsdp;
101 size_t len;
102
103 /* Read in the table signature and check it. */
104 pread(acpi_mem_fd, &rsdp, 8, addr);
105 if (memcmp(rsdp.Signature, "RSD PTR ", 8))
106 return (NULL);
107
108 /* Read the entire table. */
109 pread(acpi_mem_fd, &rsdp, sizeof(rsdp), addr);
110
111 /* Check the standard checksum. */
112 if (acpi_checksum(&rsdp, ACPI_RSDP_CHECKSUM_LENGTH) != 0)
113 return (NULL);
114
115 /* Check extended checksum if table version >= 2. */
116 if (rsdp.Revision >= 2 &&
117 acpi_checksum(&rsdp, ACPI_RSDP_XCHECKSUM_LENGTH) != 0)
118 return (NULL);
119
120 /* If the revision is 0, assume a version 1 length. */
121 if (rsdp.Revision == 0)
122 len = sizeof(ACPI_RSDP_COMMON);
123 else
124 len = rsdp.Length;
125
126 return (acpi_map_physical(addr, len));
127 }
128
129 static ACPI_TABLE_RSDP *
acpi_scan_rsd_ptr(void)130 acpi_scan_rsd_ptr(void)
131 {
132 #if defined(__amd64__) || defined(__i386__)
133 ACPI_TABLE_RSDP *rsdp;
134 u_long addr, end;
135
136 /*
137 * On ia32, scan physical memory for the RSD PTR if above failed.
138 * According to section 5.2.2 of the ACPI spec, we only consider
139 * two regions for the base address:
140 * 1. EBDA (1 KB area addressed by the 16 bit pointer at 0x40E
141 * 2. High memory (0xE0000 - 0xFFFFF)
142 */
143 addr = ACPI_EBDA_PTR_LOCATION;
144 pread(acpi_mem_fd, &addr, sizeof(uint16_t), addr);
145 addr <<= 4;
146 end = addr + ACPI_EBDA_WINDOW_SIZE;
147 for (; addr < end; addr += 16)
148 if ((rsdp = acpi_get_rsdp(addr)) != NULL)
149 return (rsdp);
150 addr = ACPI_HI_RSDP_WINDOW_BASE;
151 end = addr + ACPI_HI_RSDP_WINDOW_SIZE;
152 for (; addr < end; addr += 16)
153 if ((rsdp = acpi_get_rsdp(addr)) != NULL)
154 return (rsdp);
155 #endif /* __amd64__ || __i386__ */
156 return (NULL);
157 }
158
159 /*
160 * Public interfaces
161 */
162 ACPI_TABLE_RSDP *
acpi_find_rsd_ptr(void)163 acpi_find_rsd_ptr(void)
164 {
165 ACPI_TABLE_RSDP *rsdp;
166 char buf[20];
167 u_long addr;
168 size_t len;
169
170 acpi_user_init();
171
172 addr = 0;
173
174 /* Attempt to use kenv or sysctl to find RSD PTR record. */
175 if (kenv(KENV_GET, hint_acpi_0_rsdp, buf, 20) > 0)
176 addr = strtoul(buf, NULL, 0);
177 if (addr == 0) {
178 len = sizeof(addr);
179 if (sysctlbyname(machdep_acpi_root, &addr, &len, NULL, 0) != 0)
180 addr = 0;
181 }
182 if (addr != 0 && (rsdp = acpi_get_rsdp(addr)) != NULL)
183 return (rsdp);
184
185 return (acpi_scan_rsd_ptr());
186 }
187
188 void *
acpi_map_physical(vm_offset_t pa,size_t size)189 acpi_map_physical(vm_offset_t pa, size_t size)
190 {
191 struct acpi_user_mapping *map;
192
193 map = acpi_user_find_mapping(pa, size);
194 return (map->va + (pa - map->pa));
195 }
196
197 ACPI_TABLE_HEADER *
dsdt_load_file(char * infile)198 dsdt_load_file(char *infile)
199 {
200 ACPI_TABLE_HEADER *sdt;
201 uint8_t *dp;
202 struct stat sb;
203
204 if ((acpi_mem_fd = open(infile, O_RDONLY)) == -1)
205 errx(1, "opening %s", infile);
206
207 LIST_INIT(&maplist);
208
209 if (fstat(acpi_mem_fd, &sb) == -1)
210 errx(1, "fstat %s", infile);
211
212 dp = mmap(0, sb.st_size, PROT_READ, MAP_PRIVATE, acpi_mem_fd, 0);
213 if (dp == NULL)
214 errx(1, "mmap %s", infile);
215
216 sdt = (ACPI_TABLE_HEADER *)dp;
217 if (strncmp(dp, ACPI_SIG_DSDT, 4) != 0 ||
218 acpi_checksum(sdt, sdt->Length) != 0)
219 return (NULL);
220
221 return (sdt);
222 }
223