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 #ifndef SMBIOS_ENTRY_POINT_SCAN_START
15 #define SMBIOS_ENTRY_POINT_SCAN_START 0xF0000
16 #endif
17
18 struct kobject *dmi_kobj;
19 EXPORT_SYMBOL_GPL(dmi_kobj);
20
21 /*
22 * DMI stands for "Desktop Management Interface". It is part
23 * of and an antecedent to, SMBIOS, which stands for System
24 * Management BIOS. See further: https://www.dmtf.org/standards
25 */
26 static const char dmi_empty_string[] = "";
27
28 static u32 dmi_ver __initdata;
29 static u32 dmi_len;
30 static u16 dmi_num;
31 static u8 smbios_entry_point[32];
32 static int smbios_entry_point_size;
33
34 /* DMI system identification string used during boot */
35 static char dmi_ids_string[128] __initdata;
36
37 static struct dmi_memdev_info {
38 const char *device;
39 const char *bank;
40 u64 size; /* bytes */
41 u16 handle;
42 u8 type; /* DDR2, DDR3, DDR4 etc */
43 } *dmi_memdev;
44 static int dmi_memdev_nr;
45
dmi_string_nosave(const struct dmi_header * dm,u8 s)46 static const char * __init dmi_string_nosave(const struct dmi_header *dm, u8 s)
47 {
48 const u8 *bp = ((u8 *) dm) + dm->length;
49 const u8 *nsp;
50
51 if (s) {
52 while (--s > 0 && *bp)
53 bp += strlen(bp) + 1;
54
55 /* Strings containing only spaces are considered empty */
56 nsp = bp;
57 while (*nsp == ' ')
58 nsp++;
59 if (*nsp != '\0')
60 return bp;
61 }
62
63 return dmi_empty_string;
64 }
65
dmi_string(const struct dmi_header * dm,u8 s)66 static const char * __init dmi_string(const struct dmi_header *dm, u8 s)
67 {
68 const char *bp = dmi_string_nosave(dm, s);
69 char *str;
70 size_t len;
71
72 if (bp == dmi_empty_string)
73 return dmi_empty_string;
74
75 len = strlen(bp) + 1;
76 str = dmi_alloc(len);
77 if (str != NULL)
78 strcpy(str, bp);
79
80 return str;
81 }
82
83 /*
84 * We have to be cautious here. We have seen BIOSes with DMI pointers
85 * pointing to completely the wrong place for example
86 */
dmi_decode_table(u8 * buf,void (* decode)(const struct dmi_header *,void *),void * private_data)87 static void dmi_decode_table(u8 *buf,
88 void (*decode)(const struct dmi_header *, void *),
89 void *private_data)
90 {
91 u8 *data = buf;
92 int i = 0;
93
94 /*
95 * Stop when we have seen all the items the table claimed to have
96 * (SMBIOS < 3.0 only) OR we reach an end-of-table marker (SMBIOS
97 * >= 3.0 only) OR we run off the end of the table (should never
98 * happen but sometimes does on bogus implementations.)
99 */
100 while ((!dmi_num || i < dmi_num) &&
101 (data - buf + sizeof(struct dmi_header)) <= dmi_len) {
102 const struct dmi_header *dm = (const struct dmi_header *)data;
103
104 /*
105 * We want to know the total length (formatted area and
106 * strings) before decoding to make sure we won't run off the
107 * table in dmi_decode or dmi_string
108 */
109 data += dm->length;
110 while ((data - buf < dmi_len - 1) && (data[0] || data[1]))
111 data++;
112 if (data - buf < dmi_len - 1)
113 decode(dm, private_data);
114
115 data += 2;
116 i++;
117
118 /*
119 * 7.45 End-of-Table (Type 127) [SMBIOS reference spec v3.0.0]
120 * For tables behind a 64-bit entry point, we have no item
121 * count and no exact table length, so stop on end-of-table
122 * marker. For tables behind a 32-bit entry point, we have
123 * seen OEM structures behind the end-of-table marker on
124 * some systems, so don't trust it.
125 */
126 if (!dmi_num && dm->type == DMI_ENTRY_END_OF_TABLE)
127 break;
128 }
129
130 /* Trim DMI table length if needed */
131 if (dmi_len > data - buf)
132 dmi_len = data - buf;
133 }
134
135 static phys_addr_t dmi_base;
136
dmi_walk_early(void (* decode)(const struct dmi_header *,void *))137 static int __init dmi_walk_early(void (*decode)(const struct dmi_header *,
138 void *))
139 {
140 u8 *buf;
141 u32 orig_dmi_len = dmi_len;
142
143 buf = dmi_early_remap(dmi_base, orig_dmi_len);
144 if (buf == NULL)
145 return -ENOMEM;
146
147 dmi_decode_table(buf, decode, NULL);
148
149 add_device_randomness(buf, dmi_len);
150
151 dmi_early_unmap(buf, orig_dmi_len);
152 return 0;
153 }
154
dmi_checksum(const u8 * buf,u8 len)155 static int __init dmi_checksum(const u8 *buf, u8 len)
156 {
157 u8 sum = 0;
158 int a;
159
160 for (a = 0; a < len; a++)
161 sum += buf[a];
162
163 return sum == 0;
164 }
165
166 static const char *dmi_ident[DMI_STRING_MAX];
167 static LIST_HEAD(dmi_devices);
168 int dmi_available;
169 EXPORT_SYMBOL_GPL(dmi_available);
170
171 /*
172 * Save a DMI string
173 */
dmi_save_ident(const struct dmi_header * dm,int slot,int string)174 static void __init dmi_save_ident(const struct dmi_header *dm, int slot,
175 int string)
176 {
177 const char *d = (const char *) dm;
178 const char *p;
179
180 if (dmi_ident[slot] || dm->length <= string)
181 return;
182
183 p = dmi_string(dm, d[string]);
184 if (p == NULL)
185 return;
186
187 dmi_ident[slot] = p;
188 }
189
dmi_save_release(const struct dmi_header * dm,int slot,int index)190 static void __init dmi_save_release(const struct dmi_header *dm, int slot,
191 int index)
192 {
193 const u8 *minor, *major;
194 char *s;
195
196 /* If the table doesn't have the field, let's return */
197 if (dmi_ident[slot] || dm->length < index)
198 return;
199
200 minor = (u8 *) dm + index;
201 major = (u8 *) dm + index - 1;
202
203 /* As per the spec, if the system doesn't support this field,
204 * the value is FF
205 */
206 if (*major == 0xFF && *minor == 0xFF)
207 return;
208
209 s = dmi_alloc(8);
210 if (!s)
211 return;
212
213 sprintf(s, "%u.%u", *major, *minor);
214
215 dmi_ident[slot] = s;
216 }
217
dmi_save_uuid(const struct dmi_header * dm,int slot,int index)218 static void __init dmi_save_uuid(const struct dmi_header *dm, int slot,
219 int index)
220 {
221 const u8 *d;
222 char *s;
223 int is_ff = 1, is_00 = 1, i;
224
225 if (dmi_ident[slot] || dm->length < index + 16)
226 return;
227
228 d = (u8 *) dm + index;
229 for (i = 0; i < 16 && (is_ff || is_00); i++) {
230 if (d[i] != 0x00)
231 is_00 = 0;
232 if (d[i] != 0xFF)
233 is_ff = 0;
234 }
235
236 if (is_ff || is_00)
237 return;
238
239 s = dmi_alloc(16*2+4+1);
240 if (!s)
241 return;
242
243 /*
244 * As of version 2.6 of the SMBIOS specification, the first 3 fields of
245 * the UUID are supposed to be little-endian encoded. The specification
246 * says that this is the defacto standard.
247 */
248 if (dmi_ver >= 0x020600)
249 sprintf(s, "%pUl", d);
250 else
251 sprintf(s, "%pUb", d);
252
253 dmi_ident[slot] = s;
254 }
255
dmi_save_type(const struct dmi_header * dm,int slot,int index)256 static void __init dmi_save_type(const struct dmi_header *dm, int slot,
257 int index)
258 {
259 const u8 *d;
260 char *s;
261
262 if (dmi_ident[slot] || dm->length <= index)
263 return;
264
265 s = dmi_alloc(4);
266 if (!s)
267 return;
268
269 d = (u8 *) dm + index;
270 sprintf(s, "%u", *d & 0x7F);
271 dmi_ident[slot] = s;
272 }
273
dmi_save_one_device(int type,const char * name)274 static void __init dmi_save_one_device(int type, const char *name)
275 {
276 struct dmi_device *dev;
277
278 /* No duplicate device */
279 if (dmi_find_device(type, name, NULL))
280 return;
281
282 dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
283 if (!dev)
284 return;
285
286 dev->type = type;
287 strcpy((char *)(dev + 1), name);
288 dev->name = (char *)(dev + 1);
289 dev->device_data = NULL;
290 list_add(&dev->list, &dmi_devices);
291 }
292
dmi_save_devices(const struct dmi_header * dm)293 static void __init dmi_save_devices(const struct dmi_header *dm)
294 {
295 int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
296
297 for (i = 0; i < count; i++) {
298 const char *d = (char *)(dm + 1) + (i * 2);
299
300 /* Skip disabled device */
301 if ((*d & 0x80) == 0)
302 continue;
303
304 dmi_save_one_device(*d & 0x7f, dmi_string_nosave(dm, *(d + 1)));
305 }
306 }
307
dmi_save_oem_strings_devices(const struct dmi_header * dm)308 static void __init dmi_save_oem_strings_devices(const struct dmi_header *dm)
309 {
310 int i, count;
311 struct dmi_device *dev;
312
313 if (dm->length < 0x05)
314 return;
315
316 count = *(u8 *)(dm + 1);
317 for (i = 1; i <= count; i++) {
318 const char *devname = dmi_string(dm, i);
319
320 if (devname == dmi_empty_string)
321 continue;
322
323 dev = dmi_alloc(sizeof(*dev));
324 if (!dev)
325 break;
326
327 dev->type = DMI_DEV_TYPE_OEM_STRING;
328 dev->name = devname;
329 dev->device_data = NULL;
330
331 list_add(&dev->list, &dmi_devices);
332 }
333 }
334
dmi_save_ipmi_device(const struct dmi_header * dm)335 static void __init dmi_save_ipmi_device(const struct dmi_header *dm)
336 {
337 struct dmi_device *dev;
338 void *data;
339
340 data = dmi_alloc(dm->length);
341 if (data == NULL)
342 return;
343
344 memcpy(data, dm, dm->length);
345
346 dev = dmi_alloc(sizeof(*dev));
347 if (!dev)
348 return;
349
350 dev->type = DMI_DEV_TYPE_IPMI;
351 dev->name = "IPMI controller";
352 dev->device_data = data;
353
354 list_add_tail(&dev->list, &dmi_devices);
355 }
356
dmi_save_dev_pciaddr(int instance,int segment,int bus,int devfn,const char * name,int type)357 static void __init dmi_save_dev_pciaddr(int instance, int segment, int bus,
358 int devfn, const char *name, int type)
359 {
360 struct dmi_dev_onboard *dev;
361
362 /* Ignore invalid values */
363 if (type == DMI_DEV_TYPE_DEV_SLOT &&
364 segment == 0xFFFF && bus == 0xFF && devfn == 0xFF)
365 return;
366
367 dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
368 if (!dev)
369 return;
370
371 dev->instance = instance;
372 dev->segment = segment;
373 dev->bus = bus;
374 dev->devfn = devfn;
375
376 strcpy((char *)&dev[1], name);
377 dev->dev.type = type;
378 dev->dev.name = (char *)&dev[1];
379 dev->dev.device_data = dev;
380
381 list_add(&dev->dev.list, &dmi_devices);
382 }
383
dmi_save_extended_devices(const struct dmi_header * dm)384 static void __init dmi_save_extended_devices(const struct dmi_header *dm)
385 {
386 const char *name;
387 const u8 *d = (u8 *)dm;
388
389 if (dm->length < 0x0B)
390 return;
391
392 /* Skip disabled device */
393 if ((d[0x5] & 0x80) == 0)
394 return;
395
396 name = dmi_string_nosave(dm, d[0x4]);
397 dmi_save_dev_pciaddr(d[0x6], *(u16 *)(d + 0x7), d[0x9], d[0xA], name,
398 DMI_DEV_TYPE_DEV_ONBOARD);
399 dmi_save_one_device(d[0x5] & 0x7f, name);
400 }
401
dmi_save_system_slot(const struct dmi_header * dm)402 static void __init dmi_save_system_slot(const struct dmi_header *dm)
403 {
404 const u8 *d = (u8 *)dm;
405
406 /* Need SMBIOS 2.6+ structure */
407 if (dm->length < 0x11)
408 return;
409 dmi_save_dev_pciaddr(*(u16 *)(d + 0x9), *(u16 *)(d + 0xD), d[0xF],
410 d[0x10], dmi_string_nosave(dm, d[0x4]),
411 DMI_DEV_TYPE_DEV_SLOT);
412 }
413
count_mem_devices(const struct dmi_header * dm,void * v)414 static void __init count_mem_devices(const struct dmi_header *dm, void *v)
415 {
416 if (dm->type != DMI_ENTRY_MEM_DEVICE)
417 return;
418 dmi_memdev_nr++;
419 }
420
save_mem_devices(const struct dmi_header * dm,void * v)421 static void __init save_mem_devices(const struct dmi_header *dm, void *v)
422 {
423 const char *d = (const char *)dm;
424 static int nr;
425 u64 bytes;
426 u16 size;
427
428 if (dm->type != DMI_ENTRY_MEM_DEVICE || dm->length < 0x13)
429 return;
430 if (nr >= dmi_memdev_nr) {
431 pr_warn(FW_BUG "Too many DIMM entries in SMBIOS table\n");
432 return;
433 }
434 dmi_memdev[nr].handle = get_unaligned(&dm->handle);
435 dmi_memdev[nr].device = dmi_string(dm, d[0x10]);
436 dmi_memdev[nr].bank = dmi_string(dm, d[0x11]);
437 dmi_memdev[nr].type = d[0x12];
438
439 size = get_unaligned((u16 *)&d[0xC]);
440 if (size == 0)
441 bytes = 0;
442 else if (size == 0xffff)
443 bytes = ~0ull;
444 else if (size & 0x8000)
445 bytes = (u64)(size & 0x7fff) << 10;
446 else if (size != 0x7fff || dm->length < 0x20)
447 bytes = (u64)size << 20;
448 else
449 bytes = (u64)get_unaligned((u32 *)&d[0x1C]) << 20;
450
451 dmi_memdev[nr].size = bytes;
452 nr++;
453 }
454
dmi_memdev_walk(void)455 static void __init dmi_memdev_walk(void)
456 {
457 if (dmi_walk_early(count_mem_devices) == 0 && dmi_memdev_nr) {
458 dmi_memdev = dmi_alloc(sizeof(*dmi_memdev) * dmi_memdev_nr);
459 if (dmi_memdev)
460 dmi_walk_early(save_mem_devices);
461 }
462 }
463
464 /*
465 * Process a DMI table entry. Right now all we care about are the BIOS
466 * and machine entries. For 2.5 we should pull the smbus controller info
467 * out of here.
468 */
dmi_decode(const struct dmi_header * dm,void * dummy)469 static void __init dmi_decode(const struct dmi_header *dm, void *dummy)
470 {
471 switch (dm->type) {
472 case 0: /* BIOS Information */
473 dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
474 dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
475 dmi_save_ident(dm, DMI_BIOS_DATE, 8);
476 dmi_save_release(dm, DMI_BIOS_RELEASE, 21);
477 dmi_save_release(dm, DMI_EC_FIRMWARE_RELEASE, 23);
478 break;
479 case 1: /* System Information */
480 dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
481 dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
482 dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
483 dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
484 dmi_save_uuid(dm, DMI_PRODUCT_UUID, 8);
485 dmi_save_ident(dm, DMI_PRODUCT_SKU, 25);
486 dmi_save_ident(dm, DMI_PRODUCT_FAMILY, 26);
487 break;
488 case 2: /* Base Board Information */
489 dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
490 dmi_save_ident(dm, DMI_BOARD_NAME, 5);
491 dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
492 dmi_save_ident(dm, DMI_BOARD_SERIAL, 7);
493 dmi_save_ident(dm, DMI_BOARD_ASSET_TAG, 8);
494 break;
495 case 3: /* Chassis Information */
496 dmi_save_ident(dm, DMI_CHASSIS_VENDOR, 4);
497 dmi_save_type(dm, DMI_CHASSIS_TYPE, 5);
498 dmi_save_ident(dm, DMI_CHASSIS_VERSION, 6);
499 dmi_save_ident(dm, DMI_CHASSIS_SERIAL, 7);
500 dmi_save_ident(dm, DMI_CHASSIS_ASSET_TAG, 8);
501 break;
502 case 9: /* System Slots */
503 dmi_save_system_slot(dm);
504 break;
505 case 10: /* Onboard Devices Information */
506 dmi_save_devices(dm);
507 break;
508 case 11: /* OEM Strings */
509 dmi_save_oem_strings_devices(dm);
510 break;
511 case 38: /* IPMI Device Information */
512 dmi_save_ipmi_device(dm);
513 break;
514 case 41: /* Onboard Devices Extended Information */
515 dmi_save_extended_devices(dm);
516 }
517 }
518
print_filtered(char * buf,size_t len,const char * info)519 static int __init print_filtered(char *buf, size_t len, const char *info)
520 {
521 int c = 0;
522 const char *p;
523
524 if (!info)
525 return c;
526
527 for (p = info; *p; p++)
528 if (isprint(*p))
529 c += scnprintf(buf + c, len - c, "%c", *p);
530 else
531 c += scnprintf(buf + c, len - c, "\\x%02x", *p & 0xff);
532 return c;
533 }
534
dmi_format_ids(char * buf,size_t len)535 static void __init dmi_format_ids(char *buf, size_t len)
536 {
537 int c = 0;
538 const char *board; /* Board Name is optional */
539
540 c += print_filtered(buf + c, len - c,
541 dmi_get_system_info(DMI_SYS_VENDOR));
542 c += scnprintf(buf + c, len - c, " ");
543 c += print_filtered(buf + c, len - c,
544 dmi_get_system_info(DMI_PRODUCT_NAME));
545
546 board = dmi_get_system_info(DMI_BOARD_NAME);
547 if (board) {
548 c += scnprintf(buf + c, len - c, "/");
549 c += print_filtered(buf + c, len - c, board);
550 }
551 c += scnprintf(buf + c, len - c, ", BIOS ");
552 c += print_filtered(buf + c, len - c,
553 dmi_get_system_info(DMI_BIOS_VERSION));
554 c += scnprintf(buf + c, len - c, " ");
555 c += print_filtered(buf + c, len - c,
556 dmi_get_system_info(DMI_BIOS_DATE));
557 }
558
559 /*
560 * Check for DMI/SMBIOS headers in the system firmware image. Any
561 * SMBIOS header must start 16 bytes before the DMI header, so take a
562 * 32 byte buffer and check for DMI at offset 16 and SMBIOS at offset
563 * 0. If the DMI header is present, set dmi_ver accordingly (SMBIOS
564 * takes precedence) and return 0. Otherwise return 1.
565 */
dmi_present(const u8 * buf)566 static int __init dmi_present(const u8 *buf)
567 {
568 u32 smbios_ver;
569
570 if (memcmp(buf, "_SM_", 4) == 0 &&
571 buf[5] < 32 && dmi_checksum(buf, buf[5])) {
572 smbios_ver = get_unaligned_be16(buf + 6);
573 smbios_entry_point_size = buf[5];
574 memcpy(smbios_entry_point, buf, smbios_entry_point_size);
575
576 /* Some BIOS report weird SMBIOS version, fix that up */
577 switch (smbios_ver) {
578 case 0x021F:
579 case 0x0221:
580 pr_debug("SMBIOS version fixup (2.%d->2.%d)\n",
581 smbios_ver & 0xFF, 3);
582 smbios_ver = 0x0203;
583 break;
584 case 0x0233:
585 pr_debug("SMBIOS version fixup (2.%d->2.%d)\n", 51, 6);
586 smbios_ver = 0x0206;
587 break;
588 }
589 } else {
590 smbios_ver = 0;
591 }
592
593 buf += 16;
594
595 if (memcmp(buf, "_DMI_", 5) == 0 && dmi_checksum(buf, 15)) {
596 if (smbios_ver)
597 dmi_ver = smbios_ver;
598 else
599 dmi_ver = (buf[14] & 0xF0) << 4 | (buf[14] & 0x0F);
600 dmi_ver <<= 8;
601 dmi_num = get_unaligned_le16(buf + 12);
602 dmi_len = get_unaligned_le16(buf + 6);
603 dmi_base = get_unaligned_le32(buf + 8);
604
605 if (dmi_walk_early(dmi_decode) == 0) {
606 if (smbios_ver) {
607 pr_info("SMBIOS %d.%d present.\n",
608 dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
609 } else {
610 smbios_entry_point_size = 15;
611 memcpy(smbios_entry_point, buf,
612 smbios_entry_point_size);
613 pr_info("Legacy DMI %d.%d present.\n",
614 dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
615 }
616 dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
617 pr_info("DMI: %s\n", dmi_ids_string);
618 return 0;
619 }
620 }
621
622 return 1;
623 }
624
625 /*
626 * Check for the SMBIOS 3.0 64-bit entry point signature. Unlike the legacy
627 * 32-bit entry point, there is no embedded DMI header (_DMI_) in here.
628 */
dmi_smbios3_present(const u8 * buf)629 static int __init dmi_smbios3_present(const u8 *buf)
630 {
631 if (memcmp(buf, "_SM3_", 5) == 0 &&
632 buf[6] < 32 && dmi_checksum(buf, buf[6])) {
633 dmi_ver = get_unaligned_be32(buf + 6) & 0xFFFFFF;
634 dmi_num = 0; /* No longer specified */
635 dmi_len = get_unaligned_le32(buf + 12);
636 dmi_base = get_unaligned_le64(buf + 16);
637 smbios_entry_point_size = buf[6];
638 memcpy(smbios_entry_point, buf, smbios_entry_point_size);
639
640 if (dmi_walk_early(dmi_decode) == 0) {
641 pr_info("SMBIOS %d.%d.%d present.\n",
642 dmi_ver >> 16, (dmi_ver >> 8) & 0xFF,
643 dmi_ver & 0xFF);
644 dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
645 pr_info("DMI: %s\n", dmi_ids_string);
646 return 0;
647 }
648 }
649 return 1;
650 }
651
dmi_scan_machine(void)652 static void __init dmi_scan_machine(void)
653 {
654 char __iomem *p, *q;
655 char buf[32];
656
657 if (efi_enabled(EFI_CONFIG_TABLES)) {
658 /*
659 * According to the DMTF SMBIOS reference spec v3.0.0, it is
660 * allowed to define both the 64-bit entry point (smbios3) and
661 * the 32-bit entry point (smbios), in which case they should
662 * either both point to the same SMBIOS structure table, or the
663 * table pointed to by the 64-bit entry point should contain a
664 * superset of the table contents pointed to by the 32-bit entry
665 * point (section 5.2)
666 * This implies that the 64-bit entry point should have
667 * precedence if it is defined and supported by the OS. If we
668 * have the 64-bit entry point, but fail to decode it, fall
669 * back to the legacy one (if available)
670 */
671 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) {
672 p = dmi_early_remap(efi.smbios3, 32);
673 if (p == NULL)
674 goto error;
675 memcpy_fromio(buf, p, 32);
676 dmi_early_unmap(p, 32);
677
678 if (!dmi_smbios3_present(buf)) {
679 dmi_available = 1;
680 return;
681 }
682 }
683 if (efi.smbios == EFI_INVALID_TABLE_ADDR)
684 goto error;
685
686 /* This is called as a core_initcall() because it isn't
687 * needed during early boot. This also means we can
688 * iounmap the space when we're done with it.
689 */
690 p = dmi_early_remap(efi.smbios, 32);
691 if (p == NULL)
692 goto error;
693 memcpy_fromio(buf, p, 32);
694 dmi_early_unmap(p, 32);
695
696 if (!dmi_present(buf)) {
697 dmi_available = 1;
698 return;
699 }
700 } else if (IS_ENABLED(CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK)) {
701 p = dmi_early_remap(SMBIOS_ENTRY_POINT_SCAN_START, 0x10000);
702 if (p == NULL)
703 goto error;
704
705 /*
706 * Same logic as above, look for a 64-bit entry point
707 * first, and if not found, fall back to 32-bit entry point.
708 */
709 memcpy_fromio(buf, p, 16);
710 for (q = p + 16; q < p + 0x10000; q += 16) {
711 memcpy_fromio(buf + 16, q, 16);
712 if (!dmi_smbios3_present(buf)) {
713 dmi_available = 1;
714 dmi_early_unmap(p, 0x10000);
715 return;
716 }
717 memcpy(buf, buf + 16, 16);
718 }
719
720 /*
721 * Iterate over all possible DMI header addresses q.
722 * Maintain the 32 bytes around q in buf. On the
723 * first iteration, substitute zero for the
724 * out-of-range bytes so there is no chance of falsely
725 * detecting an SMBIOS header.
726 */
727 memset(buf, 0, 16);
728 for (q = p; q < p + 0x10000; q += 16) {
729 memcpy_fromio(buf + 16, q, 16);
730 if (!dmi_present(buf)) {
731 dmi_available = 1;
732 dmi_early_unmap(p, 0x10000);
733 return;
734 }
735 memcpy(buf, buf + 16, 16);
736 }
737 dmi_early_unmap(p, 0x10000);
738 }
739 error:
740 pr_info("DMI not present or invalid.\n");
741 }
742
raw_table_read(struct file * file,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t pos,size_t count)743 static ssize_t raw_table_read(struct file *file, struct kobject *kobj,
744 struct bin_attribute *attr, char *buf,
745 loff_t pos, size_t count)
746 {
747 memcpy(buf, attr->private + pos, count);
748 return count;
749 }
750
751 static BIN_ATTR(smbios_entry_point, S_IRUSR, raw_table_read, NULL, 0);
752 static BIN_ATTR(DMI, S_IRUSR, raw_table_read, NULL, 0);
753
dmi_init(void)754 static int __init dmi_init(void)
755 {
756 struct kobject *tables_kobj;
757 u8 *dmi_table;
758 int ret = -ENOMEM;
759
760 if (!dmi_available)
761 return 0;
762
763 /*
764 * Set up dmi directory at /sys/firmware/dmi. This entry should stay
765 * even after farther error, as it can be used by other modules like
766 * dmi-sysfs.
767 */
768 dmi_kobj = kobject_create_and_add("dmi", firmware_kobj);
769 if (!dmi_kobj)
770 goto err;
771
772 tables_kobj = kobject_create_and_add("tables", dmi_kobj);
773 if (!tables_kobj)
774 goto err;
775
776 dmi_table = dmi_remap(dmi_base, dmi_len);
777 if (!dmi_table)
778 goto err_tables;
779
780 bin_attr_smbios_entry_point.size = smbios_entry_point_size;
781 bin_attr_smbios_entry_point.private = smbios_entry_point;
782 ret = sysfs_create_bin_file(tables_kobj, &bin_attr_smbios_entry_point);
783 if (ret)
784 goto err_unmap;
785
786 bin_attr_DMI.size = dmi_len;
787 bin_attr_DMI.private = dmi_table;
788 ret = sysfs_create_bin_file(tables_kobj, &bin_attr_DMI);
789 if (!ret)
790 return 0;
791
792 sysfs_remove_bin_file(tables_kobj,
793 &bin_attr_smbios_entry_point);
794 err_unmap:
795 dmi_unmap(dmi_table);
796 err_tables:
797 kobject_del(tables_kobj);
798 kobject_put(tables_kobj);
799 err:
800 pr_err("dmi: Firmware registration failed.\n");
801
802 return ret;
803 }
804 subsys_initcall(dmi_init);
805
806 /**
807 * dmi_setup - scan and setup DMI system information
808 *
809 * Scan the DMI system information. This setups DMI identifiers
810 * (dmi_system_id) for printing it out on task dumps and prepares
811 * DIMM entry information (dmi_memdev_info) from the SMBIOS table
812 * for using this when reporting memory errors.
813 */
dmi_setup(void)814 void __init dmi_setup(void)
815 {
816 dmi_scan_machine();
817 if (!dmi_available)
818 return;
819
820 dmi_memdev_walk();
821 dump_stack_set_arch_desc("%s", dmi_ids_string);
822 }
823
824 /**
825 * dmi_matches - check if dmi_system_id structure matches system DMI data
826 * @dmi: pointer to the dmi_system_id structure to check
827 */
dmi_matches(const struct dmi_system_id * dmi)828 static bool dmi_matches(const struct dmi_system_id *dmi)
829 {
830 int i;
831
832 for (i = 0; i < ARRAY_SIZE(dmi->matches); i++) {
833 int s = dmi->matches[i].slot;
834 if (s == DMI_NONE)
835 break;
836 if (s == DMI_OEM_STRING) {
837 /* DMI_OEM_STRING must be exact match */
838 const struct dmi_device *valid;
839
840 valid = dmi_find_device(DMI_DEV_TYPE_OEM_STRING,
841 dmi->matches[i].substr, NULL);
842 if (valid)
843 continue;
844 } else if (dmi_ident[s]) {
845 if (dmi->matches[i].exact_match) {
846 if (!strcmp(dmi_ident[s],
847 dmi->matches[i].substr))
848 continue;
849 } else {
850 if (strstr(dmi_ident[s],
851 dmi->matches[i].substr))
852 continue;
853 }
854 }
855
856 /* No match */
857 return false;
858 }
859 return true;
860 }
861
862 /**
863 * dmi_is_end_of_table - check for end-of-table marker
864 * @dmi: pointer to the dmi_system_id structure to check
865 */
dmi_is_end_of_table(const struct dmi_system_id * dmi)866 static bool dmi_is_end_of_table(const struct dmi_system_id *dmi)
867 {
868 return dmi->matches[0].slot == DMI_NONE;
869 }
870
871 /**
872 * dmi_check_system - check system DMI data
873 * @list: array of dmi_system_id structures to match against
874 * All non-null elements of the list must match
875 * their slot's (field index's) data (i.e., each
876 * list string must be a substring of the specified
877 * DMI slot's string data) to be considered a
878 * successful match.
879 *
880 * Walk the blacklist table running matching functions until someone
881 * returns non zero or we hit the end. Callback function is called for
882 * each successful match. Returns the number of matches.
883 *
884 * dmi_setup must be called before this function is called.
885 */
dmi_check_system(const struct dmi_system_id * list)886 int dmi_check_system(const struct dmi_system_id *list)
887 {
888 int count = 0;
889 const struct dmi_system_id *d;
890
891 for (d = list; !dmi_is_end_of_table(d); d++)
892 if (dmi_matches(d)) {
893 count++;
894 if (d->callback && d->callback(d))
895 break;
896 }
897
898 return count;
899 }
900 EXPORT_SYMBOL(dmi_check_system);
901
902 /**
903 * dmi_first_match - find dmi_system_id structure matching system DMI data
904 * @list: array of dmi_system_id structures to match against
905 * All non-null elements of the list must match
906 * their slot's (field index's) data (i.e., each
907 * list string must be a substring of the specified
908 * DMI slot's string data) to be considered a
909 * successful match.
910 *
911 * Walk the blacklist table until the first match is found. Return the
912 * pointer to the matching entry or NULL if there's no match.
913 *
914 * dmi_setup must be called before this function is called.
915 */
dmi_first_match(const struct dmi_system_id * list)916 const struct dmi_system_id *dmi_first_match(const struct dmi_system_id *list)
917 {
918 const struct dmi_system_id *d;
919
920 for (d = list; !dmi_is_end_of_table(d); d++)
921 if (dmi_matches(d))
922 return d;
923
924 return NULL;
925 }
926 EXPORT_SYMBOL(dmi_first_match);
927
928 /**
929 * dmi_get_system_info - return DMI data value
930 * @field: data index (see enum dmi_field)
931 *
932 * Returns one DMI data value, can be used to perform
933 * complex DMI data checks.
934 */
dmi_get_system_info(int field)935 const char *dmi_get_system_info(int field)
936 {
937 return dmi_ident[field];
938 }
939 EXPORT_SYMBOL(dmi_get_system_info);
940
941 /**
942 * dmi_name_in_serial - Check if string is in the DMI product serial information
943 * @str: string to check for
944 */
dmi_name_in_serial(const char * str)945 int dmi_name_in_serial(const char *str)
946 {
947 int f = DMI_PRODUCT_SERIAL;
948 if (dmi_ident[f] && strstr(dmi_ident[f], str))
949 return 1;
950 return 0;
951 }
952
953 /**
954 * dmi_name_in_vendors - Check if string is in the DMI system or board vendor name
955 * @str: Case sensitive Name
956 */
dmi_name_in_vendors(const char * str)957 int dmi_name_in_vendors(const char *str)
958 {
959 static int fields[] = { DMI_SYS_VENDOR, DMI_BOARD_VENDOR, DMI_NONE };
960 int i;
961 for (i = 0; fields[i] != DMI_NONE; i++) {
962 int f = fields[i];
963 if (dmi_ident[f] && strstr(dmi_ident[f], str))
964 return 1;
965 }
966 return 0;
967 }
968 EXPORT_SYMBOL(dmi_name_in_vendors);
969
970 /**
971 * dmi_find_device - find onboard device by type/name
972 * @type: device type or %DMI_DEV_TYPE_ANY to match all device types
973 * @name: device name string or %NULL to match all
974 * @from: previous device found in search, or %NULL for new search.
975 *
976 * Iterates through the list of known onboard devices. If a device is
977 * found with a matching @type and @name, a pointer to its device
978 * structure is returned. Otherwise, %NULL is returned.
979 * A new search is initiated by passing %NULL as the @from argument.
980 * If @from is not %NULL, searches continue from next device.
981 */
dmi_find_device(int type,const char * name,const struct dmi_device * from)982 const struct dmi_device *dmi_find_device(int type, const char *name,
983 const struct dmi_device *from)
984 {
985 const struct list_head *head = from ? &from->list : &dmi_devices;
986 struct list_head *d;
987
988 for (d = head->next; d != &dmi_devices; d = d->next) {
989 const struct dmi_device *dev =
990 list_entry(d, struct dmi_device, list);
991
992 if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
993 ((name == NULL) || (strcmp(dev->name, name) == 0)))
994 return dev;
995 }
996
997 return NULL;
998 }
999 EXPORT_SYMBOL(dmi_find_device);
1000
1001 /**
1002 * dmi_get_date - parse a DMI date
1003 * @field: data index (see enum dmi_field)
1004 * @yearp: optional out parameter for the year
1005 * @monthp: optional out parameter for the month
1006 * @dayp: optional out parameter for the day
1007 *
1008 * The date field is assumed to be in the form resembling
1009 * [mm[/dd]]/yy[yy] and the result is stored in the out
1010 * parameters any or all of which can be omitted.
1011 *
1012 * If the field doesn't exist, all out parameters are set to zero
1013 * and false is returned. Otherwise, true is returned with any
1014 * invalid part of date set to zero.
1015 *
1016 * On return, year, month and day are guaranteed to be in the
1017 * range of [0,9999], [0,12] and [0,31] respectively.
1018 */
dmi_get_date(int field,int * yearp,int * monthp,int * dayp)1019 bool dmi_get_date(int field, int *yearp, int *monthp, int *dayp)
1020 {
1021 int year = 0, month = 0, day = 0;
1022 bool exists;
1023 const char *s, *y;
1024 char *e;
1025
1026 s = dmi_get_system_info(field);
1027 exists = s;
1028 if (!exists)
1029 goto out;
1030
1031 /*
1032 * Determine year first. We assume the date string resembles
1033 * mm/dd/yy[yy] but the original code extracted only the year
1034 * from the end. Keep the behavior in the spirit of no
1035 * surprises.
1036 */
1037 y = strrchr(s, '/');
1038 if (!y)
1039 goto out;
1040
1041 y++;
1042 year = simple_strtoul(y, &e, 10);
1043 if (y != e && year < 100) { /* 2-digit year */
1044 year += 1900;
1045 if (year < 1996) /* no dates < spec 1.0 */
1046 year += 100;
1047 }
1048 if (year > 9999) /* year should fit in %04d */
1049 year = 0;
1050
1051 /* parse the mm and dd */
1052 month = simple_strtoul(s, &e, 10);
1053 if (s == e || *e != '/' || !month || month > 12) {
1054 month = 0;
1055 goto out;
1056 }
1057
1058 s = e + 1;
1059 day = simple_strtoul(s, &e, 10);
1060 if (s == y || s == e || *e != '/' || day > 31)
1061 day = 0;
1062 out:
1063 if (yearp)
1064 *yearp = year;
1065 if (monthp)
1066 *monthp = month;
1067 if (dayp)
1068 *dayp = day;
1069 return exists;
1070 }
1071 EXPORT_SYMBOL(dmi_get_date);
1072
1073 /**
1074 * dmi_get_bios_year - get a year out of DMI_BIOS_DATE field
1075 *
1076 * Returns year on success, -ENXIO if DMI is not selected,
1077 * or a different negative error code if DMI field is not present
1078 * or not parseable.
1079 */
dmi_get_bios_year(void)1080 int dmi_get_bios_year(void)
1081 {
1082 bool exists;
1083 int year;
1084
1085 exists = dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL);
1086 if (!exists)
1087 return -ENODATA;
1088
1089 return year ? year : -ERANGE;
1090 }
1091 EXPORT_SYMBOL(dmi_get_bios_year);
1092
1093 /**
1094 * dmi_walk - Walk the DMI table and get called back for every record
1095 * @decode: Callback function
1096 * @private_data: Private data to be passed to the callback function
1097 *
1098 * Returns 0 on success, -ENXIO if DMI is not selected or not present,
1099 * or a different negative error code if DMI walking fails.
1100 */
dmi_walk(void (* decode)(const struct dmi_header *,void *),void * private_data)1101 int dmi_walk(void (*decode)(const struct dmi_header *, void *),
1102 void *private_data)
1103 {
1104 u8 *buf;
1105
1106 if (!dmi_available)
1107 return -ENXIO;
1108
1109 buf = dmi_remap(dmi_base, dmi_len);
1110 if (buf == NULL)
1111 return -ENOMEM;
1112
1113 dmi_decode_table(buf, decode, private_data);
1114
1115 dmi_unmap(buf);
1116 return 0;
1117 }
1118 EXPORT_SYMBOL_GPL(dmi_walk);
1119
1120 /**
1121 * dmi_match - compare a string to the dmi field (if exists)
1122 * @f: DMI field identifier
1123 * @str: string to compare the DMI field to
1124 *
1125 * Returns true if the requested field equals to the str (including NULL).
1126 */
dmi_match(enum dmi_field f,const char * str)1127 bool dmi_match(enum dmi_field f, const char *str)
1128 {
1129 const char *info = dmi_get_system_info(f);
1130
1131 if (info == NULL || str == NULL)
1132 return info == str;
1133
1134 return !strcmp(info, str);
1135 }
1136 EXPORT_SYMBOL_GPL(dmi_match);
1137
dmi_memdev_name(u16 handle,const char ** bank,const char ** device)1138 void dmi_memdev_name(u16 handle, const char **bank, const char **device)
1139 {
1140 int n;
1141
1142 if (dmi_memdev == NULL)
1143 return;
1144
1145 for (n = 0; n < dmi_memdev_nr; n++) {
1146 if (handle == dmi_memdev[n].handle) {
1147 *bank = dmi_memdev[n].bank;
1148 *device = dmi_memdev[n].device;
1149 break;
1150 }
1151 }
1152 }
1153 EXPORT_SYMBOL_GPL(dmi_memdev_name);
1154
dmi_memdev_size(u16 handle)1155 u64 dmi_memdev_size(u16 handle)
1156 {
1157 int n;
1158
1159 if (dmi_memdev) {
1160 for (n = 0; n < dmi_memdev_nr; n++) {
1161 if (handle == dmi_memdev[n].handle)
1162 return dmi_memdev[n].size;
1163 }
1164 }
1165 return ~0ull;
1166 }
1167 EXPORT_SYMBOL_GPL(dmi_memdev_size);
1168
1169 /**
1170 * dmi_memdev_type - get the memory type
1171 * @handle: DMI structure handle
1172 *
1173 * Return the DMI memory type of the module in the slot associated with the
1174 * given DMI handle, or 0x0 if no such DMI handle exists.
1175 */
dmi_memdev_type(u16 handle)1176 u8 dmi_memdev_type(u16 handle)
1177 {
1178 int n;
1179
1180 if (dmi_memdev) {
1181 for (n = 0; n < dmi_memdev_nr; n++) {
1182 if (handle == dmi_memdev[n].handle)
1183 return dmi_memdev[n].type;
1184 }
1185 }
1186 return 0x0; /* Not a valid value */
1187 }
1188 EXPORT_SYMBOL_GPL(dmi_memdev_type);
1189
1190 /**
1191 * dmi_memdev_handle - get the DMI handle of a memory slot
1192 * @slot: slot number
1193 *
1194 * Return the DMI handle associated with a given memory slot, or %0xFFFF
1195 * if there is no such slot.
1196 */
dmi_memdev_handle(int slot)1197 u16 dmi_memdev_handle(int slot)
1198 {
1199 if (dmi_memdev && slot >= 0 && slot < dmi_memdev_nr)
1200 return dmi_memdev[slot].handle;
1201
1202 return 0xffff; /* Not a valid value */
1203 }
1204 EXPORT_SYMBOL_GPL(dmi_memdev_handle);
1205