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 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 * 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 * 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 * 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 * 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 * 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 * 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