drivers/firmware/dmi

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This source file includes following definitions.
dmi_string_nosave
dmi_string
dmi_decode_table
dmi_walk_early
dmi_checksum
dmi_save_ident
dmi_save_uuid
dmi_save_type
dmi_save_one_device
dmi_save_devices
dmi_save_oem_strings_devices
dmi_save_ipmi_device
dmi_save_dev_pciaddr
dmi_save_extended_devices
dmi_save_system_slot
count_mem_devices
save_mem_devices
dmi_memdev_walk
dmi_decode
print_filtered
dmi_format_ids
dmi_present
dmi_smbios3_present
dmi_scan_machine
raw_table_read
dmi_init
dmi_setup
dmi_matches
dmi_is_end_of_table
dmi_check_system
dmi_first_match
dmi_get_system_info
dmi_name_in_serial
dmi_name_in_vendors
dmi_find_device
dmi_get_date
dmi_get_bios_year
dmi_walk
dmi_match
dmi_memdev_name
dmi_memdev_size
   1 // SPDX-License-Identifier: GPL-2.0-only
   2 #include <linux/types.h>
   3 #include <linux/string.h>
   4 #include <linux/init.h>
   5 #include <linux/module.h>
   6 #include <linux/ctype.h>
   7 #include <linux/dmi.h>
   8 #include <linux/efi.h>
   9 #include <linux/memblock.h>
  10 #include <linux/random.h>
  11 #include <asm/dmi.h>
  12 #include <asm/unaligned.h>
  13 
  14 struct kobject *dmi_kobj;
  15 EXPORT_SYMBOL_GPL(dmi_kobj);
  16 
  17 /*
  18  * DMI stands for "Desktop Management Interface".  It is part
  19  * of and an antecedent to, SMBIOS, which stands for System
  20  * Management BIOS.  See further: http://www.dmtf.org/standards
  21  */
  22 static const char dmi_empty_string[] = "";
  23 
  24 static u32 dmi_ver __initdata;
  25 static u32 dmi_len;
  26 static u16 dmi_num;
  27 static u8 smbios_entry_point[32];
  28 static int smbios_entry_point_size;
  29 
  30 /* DMI system identification string used during boot */
  31 static char dmi_ids_string[128] __initdata;
  32 
  33 static struct dmi_memdev_info {
  34         const char *device;
  35         const char *bank;
  36         u64 size;               /* bytes */
  37         u16 handle;
  38 } *dmi_memdev;
  39 static int dmi_memdev_nr;
  40 
  41 static const char * __init dmi_string_nosave(const struct dmi_header *dm, u8 s)
  42 {
  43         const u8 *bp = ((u8 *) dm) + dm->length;
  44         const u8 *nsp;
  45 
  46         if (s) {
  47                 while (--s > 0 && *bp)
  48                         bp += strlen(bp) + 1;
  49 
  50                 /* Strings containing only spaces are considered empty */
  51                 nsp = bp;
  52                 while (*nsp == ' ')
  53                         nsp++;
  54                 if (*nsp != '\0')
  55                         return bp;
  56         }
  57 
  58         return dmi_empty_string;
  59 }
  60 
  61 static const char * __init dmi_string(const struct dmi_header *dm, u8 s)
  62 {
  63         const char *bp = dmi_string_nosave(dm, s);
  64         char *str;
  65         size_t len;
  66 
  67         if (bp == dmi_empty_string)
  68                 return dmi_empty_string;
  69 
  70         len = strlen(bp) + 1;
  71         str = dmi_alloc(len);
  72         if (str != NULL)
  73                 strcpy(str, bp);
  74 
  75         return str;
  76 }
  77 
  78 /*
  79  *      We have to be cautious here. We have seen BIOSes with DMI pointers
  80  *      pointing to completely the wrong place for example
  81  */
  82 static void dmi_decode_table(u8 *buf,
  83                              void (*decode)(const struct dmi_header *, void *),
  84                              void *private_data)
  85 {
  86         u8 *data = buf;
  87         int i = 0;
  88 
  89         /*
  90          * Stop when we have seen all the items the table claimed to have
  91          * (SMBIOS < 3.0 only) OR we reach an end-of-table marker (SMBIOS
  92          * >= 3.0 only) OR we run off the end of the table (should never
  93          * happen but sometimes does on bogus implementations.)
  94          */
  95         while ((!dmi_num || i < dmi_num) &&
  96                (data - buf + sizeof(struct dmi_header)) <= dmi_len) {
  97                 const struct dmi_header *dm = (const struct dmi_header *)data;
  98 
  99                 /*
 100                  *  We want to know the total length (formatted area and
 101                  *  strings) before decoding to make sure we won't run off the
 102                  *  table in dmi_decode or dmi_string
 103                  */
 104                 data += dm->length;
 105                 while ((data - buf < dmi_len - 1) && (data[0] || data[1]))
 106                         data++;
 107                 if (data - buf < dmi_len - 1)
 108                         decode(dm, private_data);
 109 
 110                 data += 2;
 111                 i++;
 112 
 113                 /*
 114                  * 7.45 End-of-Table (Type 127) [SMBIOS reference spec v3.0.0]
 115                  * For tables behind a 64-bit entry point, we have no item
 116                  * count and no exact table length, so stop on end-of-table
 117                  * marker. For tables behind a 32-bit entry point, we have
 118                  * seen OEM structures behind the end-of-table marker on
 119                  * some systems, so don't trust it.
 120                  */
 121                 if (!dmi_num && dm->type == DMI_ENTRY_END_OF_TABLE)
 122                         break;
 123         }
 124 
 125         /* Trim DMI table length if needed */
 126         if (dmi_len > data - buf)
 127                 dmi_len = data - buf;
 128 }
 129 
 130 static phys_addr_t dmi_base;
 131 
 132 static int __init dmi_walk_early(void (*decode)(const struct dmi_header *,
 133                 void *))
 134 {
 135         u8 *buf;
 136         u32 orig_dmi_len = dmi_len;
 137 
 138         buf = dmi_early_remap(dmi_base, orig_dmi_len);
 139         if (buf == NULL)
 140                 return -ENOMEM;
 141 
 142         dmi_decode_table(buf, decode, NULL);
 143 
 144         add_device_randomness(buf, dmi_len);
 145 
 146         dmi_early_unmap(buf, orig_dmi_len);
 147         return 0;
 148 }
 149 
 150 static int __init dmi_checksum(const u8 *buf, u8 len)
 151 {
 152         u8 sum = 0;
 153         int a;
 154 
 155         for (a = 0; a < len; a++)
 156                 sum += buf[a];
 157 
 158         return sum == 0;
 159 }
 160 
 161 static const char *dmi_ident[DMI_STRING_MAX];
 162 static LIST_HEAD(dmi_devices);
 163 int dmi_available;
 164 
 165 /*
 166  *      Save a DMI string
 167  */
 168 static void __init dmi_save_ident(const struct dmi_header *dm, int slot,
 169                 int string)
 170 {
 171         const char *d = (const char *) dm;
 172         const char *p;
 173 
 174         if (dmi_ident[slot] || dm->length <= string)
 175                 return;
 176 
 177         p = dmi_string(dm, d[string]);
 178         if (p == NULL)
 179                 return;
 180 
 181         dmi_ident[slot] = p;
 182 }
 183 
 184 static void __init dmi_save_uuid(const struct dmi_header *dm, int slot,
 185                 int index)
 186 {
 187         const u8 *d;
 188         char *s;
 189         int is_ff = 1, is_00 = 1, i;
 190 
 191         if (dmi_ident[slot] || dm->length < index + 16)
 192                 return;
 193 
 194         d = (u8 *) dm + index;
 195         for (i = 0; i < 16 && (is_ff || is_00); i++) {
 196                 if (d[i] != 0x00)
 197                         is_00 = 0;
 198                 if (d[i] != 0xFF)
 199                         is_ff = 0;
 200         }
 201 
 202         if (is_ff || is_00)
 203                 return;
 204 
 205         s = dmi_alloc(16*2+4+1);
 206         if (!s)
 207                 return;
 208 
 209         /*
 210          * As of version 2.6 of the SMBIOS specification, the first 3 fields of
 211          * the UUID are supposed to be little-endian encoded.  The specification
 212          * says that this is the defacto standard.
 213          */
 214         if (dmi_ver >= 0x020600)
 215                 sprintf(s, "%pUl", d);
 216         else
 217                 sprintf(s, "%pUb", d);
 218 
 219         dmi_ident[slot] = s;
 220 }
 221 
 222 static void __init dmi_save_type(const struct dmi_header *dm, int slot,
 223                 int index)
 224 {
 225         const u8 *d;
 226         char *s;
 227 
 228         if (dmi_ident[slot] || dm->length <= index)
 229                 return;
 230 
 231         s = dmi_alloc(4);
 232         if (!s)
 233                 return;
 234 
 235         d = (u8 *) dm + index;
 236         sprintf(s, "%u", *d & 0x7F);
 237         dmi_ident[slot] = s;
 238 }
 239 
 240 static void __init dmi_save_one_device(int type, const char *name)
 241 {
 242         struct dmi_device *dev;
 243 
 244         /* No duplicate device */
 245         if (dmi_find_device(type, name, NULL))
 246                 return;
 247 
 248         dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
 249         if (!dev)
 250                 return;
 251 
 252         dev->type = type;
 253         strcpy((char *)(dev + 1), name);
 254         dev->name = (char *)(dev + 1);
 255         dev->device_data = NULL;
 256         list_add(&dev->list, &dmi_devices);
 257 }
 258 
 259 static void __init dmi_save_devices(const struct dmi_header *dm)
 260 {
 261         int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
 262 
 263         for (i = 0; i < count; i++) {
 264                 const char *d = (char *)(dm + 1) + (i * 2);
 265 
 266                 /* Skip disabled device */
 267                 if ((*d & 0x80) == 0)
 268                         continue;
 269 
 270                 dmi_save_one_device(*d & 0x7f, dmi_string_nosave(dm, *(d + 1)));
 271         }
 272 }
 273 
 274 static void __init dmi_save_oem_strings_devices(const struct dmi_header *dm)
 275 {
 276         int i, count;
 277         struct dmi_device *dev;
 278 
 279         if (dm->length < 0x05)
 280                 return;
 281 
 282         count = *(u8 *)(dm + 1);
 283         for (i = 1; i <= count; i++) {
 284                 const char *devname = dmi_string(dm, i);
 285 
 286                 if (devname == dmi_empty_string)
 287                         continue;
 288 
 289                 dev = dmi_alloc(sizeof(*dev));
 290                 if (!dev)
 291                         break;
 292 
 293                 dev->type = DMI_DEV_TYPE_OEM_STRING;
 294                 dev->name = devname;
 295                 dev->device_data = NULL;
 296 
 297                 list_add(&dev->list, &dmi_devices);
 298         }
 299 }
 300 
 301 static void __init dmi_save_ipmi_device(const struct dmi_header *dm)
 302 {
 303         struct dmi_device *dev;
 304         void *data;
 305 
 306         data = dmi_alloc(dm->length);
 307         if (data == NULL)
 308                 return;
 309 
 310         memcpy(data, dm, dm->length);
 311 
 312         dev = dmi_alloc(sizeof(*dev));
 313         if (!dev)
 314                 return;
 315 
 316         dev->type = DMI_DEV_TYPE_IPMI;
 317         dev->name = "IPMI controller";
 318         dev->device_data = data;
 319 
 320         list_add_tail(&dev->list, &dmi_devices);
 321 }
 322 
 323 static void __init dmi_save_dev_pciaddr(int instance, int segment, int bus,
 324                                         int devfn, const char *name, int type)
 325 {
 326         struct dmi_dev_onboard *dev;
 327 
 328         /* Ignore invalid values */
 329         if (type == DMI_DEV_TYPE_DEV_SLOT &&
 330             segment == 0xFFFF && bus == 0xFF && devfn == 0xFF)
 331                 return;
 332 
 333         dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
 334         if (!dev)
 335                 return;
 336 
 337         dev->instance = instance;
 338         dev->segment = segment;
 339         dev->bus = bus;
 340         dev->devfn = devfn;
 341 
 342         strcpy((char *)&dev[1], name);
 343         dev->dev.type = type;
 344         dev->dev.name = (char *)&dev[1];
 345         dev->dev.device_data = dev;
 346 
 347         list_add(&dev->dev.list, &dmi_devices);
 348 }
 349 
 350 static void __init dmi_save_extended_devices(const struct dmi_header *dm)
 351 {
 352         const char *name;
 353         const u8 *d = (u8 *)dm;
 354 
 355         if (dm->length < 0x0B)
 356                 return;
 357 
 358         /* Skip disabled device */
 359         if ((d[0x5] & 0x80) == 0)
 360                 return;
 361 
 362         name = dmi_string_nosave(dm, d[0x4]);
 363         dmi_save_dev_pciaddr(d[0x6], *(u16 *)(d + 0x7), d[0x9], d[0xA], name,
 364                              DMI_DEV_TYPE_DEV_ONBOARD);
 365         dmi_save_one_device(d[0x5] & 0x7f, name);
 366 }
 367 
 368 static void __init dmi_save_system_slot(const struct dmi_header *dm)
 369 {
 370         const u8 *d = (u8 *)dm;
 371 
 372         /* Need SMBIOS 2.6+ structure */
 373         if (dm->length < 0x11)
 374                 return;
 375         dmi_save_dev_pciaddr(*(u16 *)(d + 0x9), *(u16 *)(d + 0xD), d[0xF],
 376                              d[0x10], dmi_string_nosave(dm, d[0x4]),
 377                              DMI_DEV_TYPE_DEV_SLOT);
 378 }
 379 
 380 static void __init count_mem_devices(const struct dmi_header *dm, void *v)
 381 {
 382         if (dm->type != DMI_ENTRY_MEM_DEVICE)
 383                 return;
 384         dmi_memdev_nr++;
 385 }
 386 
 387 static void __init save_mem_devices(const struct dmi_header *dm, void *v)
 388 {
 389         const char *d = (const char *)dm;
 390         static int nr;
 391         u64 bytes;
 392         u16 size;
 393 
 394         if (dm->type != DMI_ENTRY_MEM_DEVICE || dm->length < 0x12)
 395                 return;
 396         if (nr >= dmi_memdev_nr) {
 397                 pr_warn(FW_BUG "Too many DIMM entries in SMBIOS table\n");
 398                 return;
 399         }
 400         dmi_memdev[nr].handle = get_unaligned(&dm->handle);
 401         dmi_memdev[nr].device = dmi_string(dm, d[0x10]);
 402         dmi_memdev[nr].bank = dmi_string(dm, d[0x11]);
 403 
 404         size = get_unaligned((u16 *)&d[0xC]);
 405         if (size == 0)
 406                 bytes = 0;
 407         else if (size == 0xffff)
 408                 bytes = ~0ull;
 409         else if (size & 0x8000)
 410                 bytes = (u64)(size & 0x7fff) << 10;
 411         else if (size != 0x7fff || dm->length < 0x20)
 412                 bytes = (u64)size << 20;
 413         else
 414                 bytes = (u64)get_unaligned((u32 *)&d[0x1C]) << 20;
 415 
 416         dmi_memdev[nr].size = bytes;
 417         nr++;
 418 }
 419 
 420 static void __init dmi_memdev_walk(void)
 421 {
 422         if (dmi_walk_early(count_mem_devices) == 0 && dmi_memdev_nr) {
 423                 dmi_memdev = dmi_alloc(sizeof(*dmi_memdev) * dmi_memdev_nr);
 424                 if (dmi_memdev)
 425                         dmi_walk_early(save_mem_devices);
 426         }
 427 }
 428 
 429 /*
 430  *      Process a DMI table entry. Right now all we care about are the BIOS
 431  *      and machine entries. For 2.5 we should pull the smbus controller info
 432  *      out of here.
 433  */
 434 static void __init dmi_decode(const struct dmi_header *dm, void *dummy)
 435 {
 436         switch (dm->type) {
 437         case 0:         /* BIOS Information */
 438                 dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
 439                 dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
 440                 dmi_save_ident(dm, DMI_BIOS_DATE, 8);
 441                 break;
 442         case 1:         /* System Information */
 443                 dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
 444                 dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
 445                 dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
 446                 dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
 447                 dmi_save_uuid(dm, DMI_PRODUCT_UUID, 8);
 448                 dmi_save_ident(dm, DMI_PRODUCT_SKU, 25);
 449                 dmi_save_ident(dm, DMI_PRODUCT_FAMILY, 26);
 450                 break;
 451         case 2:         /* Base Board Information */
 452                 dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
 453                 dmi_save_ident(dm, DMI_BOARD_NAME, 5);
 454                 dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
 455                 dmi_save_ident(dm, DMI_BOARD_SERIAL, 7);
 456                 dmi_save_ident(dm, DMI_BOARD_ASSET_TAG, 8);
 457                 break;
 458         case 3:         /* Chassis Information */
 459                 dmi_save_ident(dm, DMI_CHASSIS_VENDOR, 4);
 460                 dmi_save_type(dm, DMI_CHASSIS_TYPE, 5);
 461                 dmi_save_ident(dm, DMI_CHASSIS_VERSION, 6);
 462                 dmi_save_ident(dm, DMI_CHASSIS_SERIAL, 7);
 463                 dmi_save_ident(dm, DMI_CHASSIS_ASSET_TAG, 8);
 464                 break;
 465         case 9:         /* System Slots */
 466                 dmi_save_system_slot(dm);
 467                 break;
 468         case 10:        /* Onboard Devices Information */
 469                 dmi_save_devices(dm);
 470                 break;
 471         case 11:        /* OEM Strings */
 472                 dmi_save_oem_strings_devices(dm);
 473                 break;
 474         case 38:        /* IPMI Device Information */
 475                 dmi_save_ipmi_device(dm);
 476                 break;
 477         case 41:        /* Onboard Devices Extended Information */
 478                 dmi_save_extended_devices(dm);
 479         }
 480 }
 481 
 482 static int __init print_filtered(char *buf, size_t len, const char *info)
 483 {
 484         int c = 0;
 485         const char *p;
 486 
 487         if (!info)
 488                 return c;
 489 
 490         for (p = info; *p; p++)
 491                 if (isprint(*p))
 492                         c += scnprintf(buf + c, len - c, "%c", *p);
 493                 else
 494                         c += scnprintf(buf + c, len - c, "\\x%02x", *p & 0xff);
 495         return c;
 496 }
 497 
 498 static void __init dmi_format_ids(char *buf, size_t len)
 499 {
 500         int c = 0;
 501         const char *board;      /* Board Name is optional */
 502 
 503         c += print_filtered(buf + c, len - c,
 504                             dmi_get_system_info(DMI_SYS_VENDOR));
 505         c += scnprintf(buf + c, len - c, " ");
 506         c += print_filtered(buf + c, len - c,
 507                             dmi_get_system_info(DMI_PRODUCT_NAME));
 508 
 509         board = dmi_get_system_info(DMI_BOARD_NAME);
 510         if (board) {
 511                 c += scnprintf(buf + c, len - c, "/");
 512                 c += print_filtered(buf + c, len - c, board);
 513         }
 514         c += scnprintf(buf + c, len - c, ", BIOS ");
 515         c += print_filtered(buf + c, len - c,
 516                             dmi_get_system_info(DMI_BIOS_VERSION));
 517         c += scnprintf(buf + c, len - c, " ");
 518         c += print_filtered(buf + c, len - c,
 519                             dmi_get_system_info(DMI_BIOS_DATE));
 520 }
 521 
 522 /*
 523  * Check for DMI/SMBIOS headers in the system firmware image.  Any
 524  * SMBIOS header must start 16 bytes before the DMI header, so take a
 525  * 32 byte buffer and check for DMI at offset 16 and SMBIOS at offset
 526  * 0.  If the DMI header is present, set dmi_ver accordingly (SMBIOS
 527  * takes precedence) and return 0.  Otherwise return 1.
 528  */
 529 static int __init dmi_present(const u8 *buf)
 530 {
 531         u32 smbios_ver;
 532 
 533         if (memcmp(buf, "_SM_", 4) == 0 &&
 534             buf[5] < 32 && dmi_checksum(buf, buf[5])) {
 535                 smbios_ver = get_unaligned_be16(buf + 6);
 536                 smbios_entry_point_size = buf[5];
 537                 memcpy(smbios_entry_point, buf, smbios_entry_point_size);
 538 
 539                 /* Some BIOS report weird SMBIOS version, fix that up */
 540                 switch (smbios_ver) {
 541                 case 0x021F:
 542                 case 0x0221:
 543                         pr_debug("SMBIOS version fixup (2.%d->2.%d)\n",
 544                                  smbios_ver & 0xFF, 3);
 545                         smbios_ver = 0x0203;
 546                         break;
 547                 case 0x0233:
 548                         pr_debug("SMBIOS version fixup (2.%d->2.%d)\n", 51, 6);
 549                         smbios_ver = 0x0206;
 550                         break;
 551                 }
 552         } else {
 553                 smbios_ver = 0;
 554         }
 555 
 556         buf += 16;
 557 
 558         if (memcmp(buf, "_DMI_", 5) == 0 && dmi_checksum(buf, 15)) {
 559                 if (smbios_ver)
 560                         dmi_ver = smbios_ver;
 561                 else
 562                         dmi_ver = (buf[14] & 0xF0) << 4 | (buf[14] & 0x0F);
 563                 dmi_ver <<= 8;
 564                 dmi_num = get_unaligned_le16(buf + 12);
 565                 dmi_len = get_unaligned_le16(buf + 6);
 566                 dmi_base = get_unaligned_le32(buf + 8);
 567 
 568                 if (dmi_walk_early(dmi_decode) == 0) {
 569                         if (smbios_ver) {
 570                                 pr_info("SMBIOS %d.%d present.\n",
 571                                         dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
 572                         } else {
 573                                 smbios_entry_point_size = 15;
 574                                 memcpy(smbios_entry_point, buf,
 575                                        smbios_entry_point_size);
 576                                 pr_info("Legacy DMI %d.%d present.\n",
 577                                         dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
 578                         }
 579                         dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
 580                         pr_info("DMI: %s\n", dmi_ids_string);
 581                         return 0;
 582                 }
 583         }
 584 
 585         return 1;
 586 }
 587 
 588 /*
 589  * Check for the SMBIOS 3.0 64-bit entry point signature. Unlike the legacy
 590  * 32-bit entry point, there is no embedded DMI header (_DMI_) in here.
 591  */
 592 static int __init dmi_smbios3_present(const u8 *buf)
 593 {
 594         if (memcmp(buf, "_SM3_", 5) == 0 &&
 595             buf[6] < 32 && dmi_checksum(buf, buf[6])) {
 596                 dmi_ver = get_unaligned_be32(buf + 6) & 0xFFFFFF;
 597                 dmi_num = 0;                    /* No longer specified */
 598                 dmi_len = get_unaligned_le32(buf + 12);
 599                 dmi_base = get_unaligned_le64(buf + 16);
 600                 smbios_entry_point_size = buf[6];
 601                 memcpy(smbios_entry_point, buf, smbios_entry_point_size);
 602 
 603                 if (dmi_walk_early(dmi_decode) == 0) {
 604                         pr_info("SMBIOS %d.%d.%d present.\n",
 605                                 dmi_ver >> 16, (dmi_ver >> 8) & 0xFF,
 606                                 dmi_ver & 0xFF);
 607                         dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
 608                         pr_info("DMI: %s\n", dmi_ids_string);
 609                         return 0;
 610                 }
 611         }
 612         return 1;
 613 }
 614 
 615 static void __init dmi_scan_machine(void)
 616 {
 617         char __iomem *p, *q;
 618         char buf[32];
 619 
 620         if (efi_enabled(EFI_CONFIG_TABLES)) {
 621                 /*
 622                  * According to the DMTF SMBIOS reference spec v3.0.0, it is
 623                  * allowed to define both the 64-bit entry point (smbios3) and
 624                  * the 32-bit entry point (smbios), in which case they should
 625                  * either both point to the same SMBIOS structure table, or the
 626                  * table pointed to by the 64-bit entry point should contain a
 627                  * superset of the table contents pointed to by the 32-bit entry
 628                  * point (section 5.2)
 629                  * This implies that the 64-bit entry point should have
 630                  * precedence if it is defined and supported by the OS. If we
 631                  * have the 64-bit entry point, but fail to decode it, fall
 632                  * back to the legacy one (if available)
 633                  */
 634                 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) {
 635                         p = dmi_early_remap(efi.smbios3, 32);
 636                         if (p == NULL)
 637                                 goto error;
 638                         memcpy_fromio(buf, p, 32);
 639                         dmi_early_unmap(p, 32);
 640 
 641                         if (!dmi_smbios3_present(buf)) {
 642                                 dmi_available = 1;
 643                                 return;
 644                         }
 645                 }
 646                 if (efi.smbios == EFI_INVALID_TABLE_ADDR)
 647                         goto error;
 648 
 649                 /* This is called as a core_initcall() because it isn't
 650                  * needed during early boot.  This also means we can
 651                  * iounmap the space when we're done with it.
 652                  */
 653                 p = dmi_early_remap(efi.smbios, 32);
 654                 if (p == NULL)
 655                         goto error;
 656                 memcpy_fromio(buf, p, 32);
 657                 dmi_early_unmap(p, 32);
 658 
 659                 if (!dmi_present(buf)) {
 660                         dmi_available = 1;
 661                         return;
 662                 }
 663         } else if (IS_ENABLED(CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK)) {
 664                 p = dmi_early_remap(0xF0000, 0x10000);
 665                 if (p == NULL)
 666                         goto error;
 667 
 668                 /*
 669                  * Same logic as above, look for a 64-bit entry point
 670                  * first, and if not found, fall back to 32-bit entry point.
 671                  */
 672                 memcpy_fromio(buf, p, 16);
 673                 for (q = p + 16; q < p + 0x10000; q += 16) {
 674                         memcpy_fromio(buf + 16, q, 16);
 675                         if (!dmi_smbios3_present(buf)) {
 676                                 dmi_available = 1;
 677                                 dmi_early_unmap(p, 0x10000);
 678                                 return;
 679                         }
 680                         memcpy(buf, buf + 16, 16);
 681                 }
 682 
 683                 /*
 684                  * Iterate over all possible DMI header addresses q.
 685                  * Maintain the 32 bytes around q in buf.  On the
 686                  * first iteration, substitute zero for the
 687                  * out-of-range bytes so there is no chance of falsely
 688                  * detecting an SMBIOS header.
 689                  */
 690                 memset(buf, 0, 16);
 691                 for (q = p; q < p + 0x10000; q += 16) {
 692                         memcpy_fromio(buf + 16, q, 16);
 693                         if (!dmi_present(buf)) {
 694                                 dmi_available = 1;
 695                                 dmi_early_unmap(p, 0x10000);
 696                                 return;
 697                         }
 698                         memcpy(buf, buf + 16, 16);
 699                 }
 700                 dmi_early_unmap(p, 0x10000);
 701         }
 702  error:
 703         pr_info("DMI not present or invalid.\n");
 704 }
 705 
 706 static ssize_t raw_table_read(struct file *file, struct kobject *kobj,
 707                               struct bin_attribute *attr, char *buf,
 708                               loff_t pos, size_t count)
 709 {
 710         memcpy(buf, attr->private + pos, count);
 711         return count;
 712 }
 713 
 714 static BIN_ATTR(smbios_entry_point, S_IRUSR, raw_table_read, NULL, 0);
 715 static BIN_ATTR(DMI, S_IRUSR, raw_table_read, NULL, 0);
 716 
 717 static int __init dmi_init(void)
 718 {
 719         struct kobject *tables_kobj;
 720         u8 *dmi_table;
 721         int ret = -ENOMEM;
 722 
 723         if (!dmi_available)
 724                 return 0;
 725 
 726         /*
 727          * Set up dmi directory at /sys/firmware/dmi. This entry should stay
 728          * even after farther error, as it can be used by other modules like
 729          * dmi-sysfs.
 730          */
 731         dmi_kobj = kobject_create_and_add("dmi", firmware_kobj);
 732         if (!dmi_kobj)
 733                 goto err;
 734 
 735         tables_kobj = kobject_create_and_add("tables", dmi_kobj);
 736         if (!tables_kobj)
 737                 goto err;
 738 
 739         dmi_table = dmi_remap(dmi_base, dmi_len);
 740         if (!dmi_table)
 741                 goto err_tables;
 742 
 743         bin_attr_smbios_entry_point.size = smbios_entry_point_size;
 744         bin_attr_smbios_entry_point.private = smbios_entry_point;
 745         ret = sysfs_create_bin_file(tables_kobj, &bin_attr_smbios_entry_point);
 746         if (ret)
 747                 goto err_unmap;
 748 
 749         bin_attr_DMI.size = dmi_len;
 750         bin_attr_DMI.private = dmi_table;
 751         ret = sysfs_create_bin_file(tables_kobj, &bin_attr_DMI);
 752         if (!ret)
 753                 return 0;
 754 
 755         sysfs_remove_bin_file(tables_kobj,
 756                               &bin_attr_smbios_entry_point);
 757  err_unmap:
 758         dmi_unmap(dmi_table);
 759  err_tables:
 760         kobject_del(tables_kobj);
 761         kobject_put(tables_kobj);
 762  err:
 763         pr_err("dmi: Firmware registration failed.\n");
 764 
 765         return ret;
 766 }
 767 subsys_initcall(dmi_init);
 768 
 769 /**
 770  *      dmi_setup - scan and setup DMI system information
 771  *
 772  *      Scan the DMI system information. This setups DMI identifiers
 773  *      (dmi_system_id) for printing it out on task dumps and prepares
 774  *      DIMM entry information (dmi_memdev_info) from the SMBIOS table
 775  *      for using this when reporting memory errors.
 776  */
 777 void __init dmi_setup(void)
 778 {
 779         dmi_scan_machine();
 780         if (!dmi_available)
 781                 return;
 782 
 783         dmi_memdev_walk();
 784         dump_stack_set_arch_desc("%s", dmi_ids_string);
 785 }
 786 
 787 /**
 788  *      dmi_matches - check if dmi_system_id structure matches system DMI data
 789  *      @dmi: pointer to the dmi_system_id structure to check
 790  */
 791 static bool dmi_matches(const struct dmi_system_id *dmi)
 792 {
 793         int i;
 794 
 795         for (i = 0; i < ARRAY_SIZE(dmi->matches); i++) {
 796                 int s = dmi->matches[i].slot;
 797                 if (s == DMI_NONE)
 798                         break;
 799                 if (s == DMI_OEM_STRING) {
 800                         /* DMI_OEM_STRING must be exact match */
 801                         const struct dmi_device *valid;
 802 
 803                         valid = dmi_find_device(DMI_DEV_TYPE_OEM_STRING,
 804                                                 dmi->matches[i].substr, NULL);
 805                         if (valid)
 806                                 continue;
 807                 } else if (dmi_ident[s]) {
 808                         if (dmi->matches[i].exact_match) {
 809                                 if (!strcmp(dmi_ident[s],
 810                                             dmi->matches[i].substr))
 811                                         continue;
 812                         } else {
 813                                 if (strstr(dmi_ident[s],
 814                                            dmi->matches[i].substr))
 815                                         continue;
 816                         }
 817                 }
 818 
 819                 /* No match */
 820                 return false;
 821         }
 822         return true;
 823 }
 824 
 825 /**
 826  *      dmi_is_end_of_table - check for end-of-table marker
 827  *      @dmi: pointer to the dmi_system_id structure to check
 828  */
 829 static bool dmi_is_end_of_table(const struct dmi_system_id *dmi)
 830 {
 831         return dmi->matches[0].slot == DMI_NONE;
 832 }
 833 
 834 /**
 835  *      dmi_check_system - check system DMI data
 836  *      @list: array of dmi_system_id structures to match against
 837  *              All non-null elements of the list must match
 838  *              their slot's (field index's) data (i.e., each
 839  *              list string must be a substring of the specified
 840  *              DMI slot's string data) to be considered a
 841  *              successful match.
 842  *
 843  *      Walk the blacklist table running matching functions until someone
 844  *      returns non zero or we hit the end. Callback function is called for
 845  *      each successful match. Returns the number of matches.
 846  *
 847  *      dmi_setup must be called before this function is called.
 848  */
 849 int dmi_check_system(const struct dmi_system_id *list)
 850 {
 851         int count = 0;
 852         const struct dmi_system_id *d;
 853 
 854         for (d = list; !dmi_is_end_of_table(d); d++)
 855                 if (dmi_matches(d)) {
 856                         count++;
 857                         if (d->callback && d->callback(d))
 858                                 break;
 859                 }
 860 
 861         return count;
 862 }
 863 EXPORT_SYMBOL(dmi_check_system);
 864 
 865 /**
 866  *      dmi_first_match - find dmi_system_id structure matching system DMI data
 867  *      @list: array of dmi_system_id structures to match against
 868  *              All non-null elements of the list must match
 869  *              their slot's (field index's) data (i.e., each
 870  *              list string must be a substring of the specified
 871  *              DMI slot's string data) to be considered a
 872  *              successful match.
 873  *
 874  *      Walk the blacklist table until the first match is found.  Return the
 875  *      pointer to the matching entry or NULL if there's no match.
 876  *
 877  *      dmi_setup must be called before this function is called.
 878  */
 879 const struct dmi_system_id *dmi_first_match(const struct dmi_system_id *list)
 880 {
 881         const struct dmi_system_id *d;
 882 
 883         for (d = list; !dmi_is_end_of_table(d); d++)
 884                 if (dmi_matches(d))
 885                         return d;
 886 
 887         return NULL;
 888 }
 889 EXPORT_SYMBOL(dmi_first_match);
 890 
 891 /**
 892  *      dmi_get_system_info - return DMI data value
 893  *      @field: data index (see enum dmi_field)
 894  *
 895  *      Returns one DMI data value, can be used to perform
 896  *      complex DMI data checks.
 897  */
 898 const char *dmi_get_system_info(int field)
 899 {
 900         return dmi_ident[field];
 901 }
 902 EXPORT_SYMBOL(dmi_get_system_info);
 903 
 904 /**
 905  * dmi_name_in_serial - Check if string is in the DMI product serial information
 906  * @str: string to check for
 907  */
 908 int dmi_name_in_serial(const char *str)
 909 {
 910         int f = DMI_PRODUCT_SERIAL;
 911         if (dmi_ident[f] && strstr(dmi_ident[f], str))
 912                 return 1;
 913         return 0;
 914 }
 915 
 916 /**
 917  *      dmi_name_in_vendors - Check if string is in the DMI system or board vendor name
 918  *      @str: Case sensitive Name
 919  */
 920 int dmi_name_in_vendors(const char *str)
 921 {
 922         static int fields[] = { DMI_SYS_VENDOR, DMI_BOARD_VENDOR, DMI_NONE };
 923         int i;
 924         for (i = 0; fields[i] != DMI_NONE; i++) {
 925                 int f = fields[i];
 926                 if (dmi_ident[f] && strstr(dmi_ident[f], str))
 927                         return 1;
 928         }
 929         return 0;
 930 }
 931 EXPORT_SYMBOL(dmi_name_in_vendors);
 932 
 933 /**
 934  *      dmi_find_device - find onboard device by type/name
 935  *      @type: device type or %DMI_DEV_TYPE_ANY to match all device types
 936  *      @name: device name string or %NULL to match all
 937  *      @from: previous device found in search, or %NULL for new search.
 938  *
 939  *      Iterates through the list of known onboard devices. If a device is
 940  *      found with a matching @type and @name, a pointer to its device
 941  *      structure is returned.  Otherwise, %NULL is returned.
 942  *      A new search is initiated by passing %NULL as the @from argument.
 943  *      If @from is not %NULL, searches continue from next device.
 944  */
 945 const struct dmi_device *dmi_find_device(int type, const char *name,
 946                                     const struct dmi_device *from)
 947 {
 948         const struct list_head *head = from ? &from->list : &dmi_devices;
 949         struct list_head *d;
 950 
 951         for (d = head->next; d != &dmi_devices; d = d->next) {
 952                 const struct dmi_device *dev =
 953                         list_entry(d, struct dmi_device, list);
 954 
 955                 if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
 956                     ((name == NULL) || (strcmp(dev->name, name) == 0)))
 957                         return dev;
 958         }
 959 
 960         return NULL;
 961 }
 962 EXPORT_SYMBOL(dmi_find_device);
 963 
 964 /**
 965  *      dmi_get_date - parse a DMI date
 966  *      @field: data index (see enum dmi_field)
 967  *      @yearp: optional out parameter for the year
 968  *      @monthp: optional out parameter for the month
 969  *      @dayp: optional out parameter for the day
 970  *
 971  *      The date field is assumed to be in the form resembling
 972  *      [mm[/dd]]/yy[yy] and the result is stored in the out
 973  *      parameters any or all of which can be omitted.
 974  *
 975  *      If the field doesn't exist, all out parameters are set to zero
 976  *      and false is returned.  Otherwise, true is returned with any
 977  *      invalid part of date set to zero.
 978  *
 979  *      On return, year, month and day are guaranteed to be in the
 980  *      range of [0,9999], [0,12] and [0,31] respectively.
 981  */
 982 bool dmi_get_date(int field, int *yearp, int *monthp, int *dayp)
 983 {
 984         int year = 0, month = 0, day = 0;
 985         bool exists;
 986         const char *s, *y;
 987         char *e;
 988 
 989         s = dmi_get_system_info(field);
 990         exists = s;
 991         if (!exists)
 992                 goto out;
 993 
 994         /*
 995          * Determine year first.  We assume the date string resembles
 996          * mm/dd/yy[yy] but the original code extracted only the year
 997          * from the end.  Keep the behavior in the spirit of no
 998          * surprises.
 999          */
1000         y = strrchr(s, '/');
1001         if (!y)
1002                 goto out;
1003 
1004         y++;
1005         year = simple_strtoul(y, &e, 10);
1006         if (y != e && year < 100) {     /* 2-digit year */
1007                 year += 1900;
1008                 if (year < 1996)        /* no dates < spec 1.0 */
1009                         year += 100;
1010         }
1011         if (year > 9999)                /* year should fit in %04d */
1012                 year = 0;
1013 
1014         /* parse the mm and dd */
1015         month = simple_strtoul(s, &e, 10);
1016         if (s == e || *e != '/' || !month || month > 12) {
1017                 month = 0;
1018                 goto out;
1019         }
1020 
1021         s = e + 1;
1022         day = simple_strtoul(s, &e, 10);
1023         if (s == y || s == e || *e != '/' || day > 31)
1024                 day = 0;
1025 out:
1026         if (yearp)
1027                 *yearp = year;
1028         if (monthp)
1029                 *monthp = month;
1030         if (dayp)
1031                 *dayp = day;
1032         return exists;
1033 }
1034 EXPORT_SYMBOL(dmi_get_date);
1035 
1036 /**
1037  *      dmi_get_bios_year - get a year out of DMI_BIOS_DATE field
1038  *
1039  *      Returns year on success, -ENXIO if DMI is not selected,
1040  *      or a different negative error code if DMI field is not present
1041  *      or not parseable.
1042  */
1043 int dmi_get_bios_year(void)
1044 {
1045         bool exists;
1046         int year;
1047 
1048         exists = dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL);
1049         if (!exists)
1050                 return -ENODATA;
1051 
1052         return year ? year : -ERANGE;
1053 }
1054 EXPORT_SYMBOL(dmi_get_bios_year);
1055 
1056 /**
1057  *      dmi_walk - Walk the DMI table and get called back for every record
1058  *      @decode: Callback function
1059  *      @private_data: Private data to be passed to the callback function
1060  *
1061  *      Returns 0 on success, -ENXIO if DMI is not selected or not present,
1062  *      or a different negative error code if DMI walking fails.
1063  */
1064 int dmi_walk(void (*decode)(const struct dmi_header *, void *),
1065              void *private_data)
1066 {
1067         u8 *buf;
1068 
1069         if (!dmi_available)
1070                 return -ENXIO;
1071 
1072         buf = dmi_remap(dmi_base, dmi_len);
1073         if (buf == NULL)
1074                 return -ENOMEM;
1075 
1076         dmi_decode_table(buf, decode, private_data);
1077 
1078         dmi_unmap(buf);
1079         return 0;
1080 }
1081 EXPORT_SYMBOL_GPL(dmi_walk);
1082 
1083 /**
1084  * dmi_match - compare a string to the dmi field (if exists)
1085  * @f: DMI field identifier
1086  * @str: string to compare the DMI field to
1087  *
1088  * Returns true if the requested field equals to the str (including NULL).
1089  */
1090 bool dmi_match(enum dmi_field f, const char *str)
1091 {
1092         const char *info = dmi_get_system_info(f);
1093 
1094         if (info == NULL || str == NULL)
1095                 return info == str;
1096 
1097         return !strcmp(info, str);
1098 }
1099 EXPORT_SYMBOL_GPL(dmi_match);
1100 
1101 void dmi_memdev_name(u16 handle, const char **bank, const char **device)
1102 {
1103         int n;
1104 
1105         if (dmi_memdev == NULL)
1106                 return;
1107 
1108         for (n = 0; n < dmi_memdev_nr; n++) {
1109                 if (handle == dmi_memdev[n].handle) {
1110                         *bank = dmi_memdev[n].bank;
1111                         *device = dmi_memdev[n].device;
1112                         break;
1113                 }
1114         }
1115 }
1116 EXPORT_SYMBOL_GPL(dmi_memdev_name);
1117 
1118 u64 dmi_memdev_size(u16 handle)
1119 {
1120         int n;
1121 
1122         if (dmi_memdev) {
1123                 for (n = 0; n < dmi_memdev_nr; n++) {
1124                         if (handle == dmi_memdev[n].handle)
1125                                 return dmi_memdev[n].size;
1126                 }
1127         }
1128         return ~0ull;
1129 }
1130 EXPORT_SYMBOL_GPL(dmi_memdev_size);
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/firmware/dmi_scan.c

DEFINITIONS
