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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 <linux/unaligned.h>
13
14#ifndef SMBIOS_ENTRY_POINT_SCAN_START
15#define SMBIOS_ENTRY_POINT_SCAN_START 0xF0000
16#endif
17
18struct kobject *dmi_kobj;
19EXPORT_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 */
26static const char dmi_empty_string[] = "";
27
28static u32 dmi_ver __initdata;
29static u32 dmi_len;
30static u16 dmi_num;
31static u8 smbios_entry_point[32];
32static int smbios_entry_point_size;
33
34/* DMI system identification string used during boot */
35static char dmi_ids_string[128] __initdata;
36
37static 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;
44static int dmi_memdev_nr;
45static int dmi_memdev_populated_nr __initdata;
46
47static const char * __init dmi_string_nosave(const struct dmi_header *dm, u8 s)
48{
49 const u8 *bp = ((u8 *) dm) + dm->length;
50 const u8 *nsp;
51
52 if (s) {
53 while (--s > 0 && *bp)
54 bp += strlen(bp) + 1;
55
56 /* Strings containing only spaces are considered empty */
57 nsp = bp;
58 while (*nsp == ' ')
59 nsp++;
60 if (*nsp != '\0')
61 return bp;
62 }
63
64 return dmi_empty_string;
65}
66
67static const char * __init dmi_string(const struct dmi_header *dm, u8 s)
68{
69 const char *bp = dmi_string_nosave(dm, s);
70 char *str;
71 size_t len;
72
73 if (bp == dmi_empty_string)
74 return dmi_empty_string;
75
76 len = strlen(bp) + 1;
77 str = dmi_alloc(len);
78 if (str != NULL)
79 strcpy(str, bp);
80
81 return str;
82}
83
84/*
85 * We have to be cautious here. We have seen BIOSes with DMI pointers
86 * pointing to completely the wrong place for example
87 */
88static void dmi_decode_table(u8 *buf,
89 void (*decode)(const struct dmi_header *, void *),
90 void *private_data)
91{
92 u8 *data = buf;
93 int i = 0;
94
95 /*
96 * Stop when we have seen all the items the table claimed to have
97 * (SMBIOS < 3.0 only) OR we reach an end-of-table marker (SMBIOS
98 * >= 3.0 only) OR we run off the end of the table (should never
99 * happen but sometimes does on bogus implementations.)
100 */
101 while ((!dmi_num || i < dmi_num) &&
102 (data - buf + sizeof(struct dmi_header)) <= dmi_len) {
103 const struct dmi_header *dm = (const struct dmi_header *)data;
104
105 /*
106 * If a short entry is found (less than 4 bytes), not only it
107 * is invalid, but we cannot reliably locate the next entry.
108 */
109 if (dm->length < sizeof(struct dmi_header)) {
110 pr_warn(FW_BUG
111 "Corrupted DMI table, offset %zd (only %d entries processed)\n",
112 data - buf, i);
113 break;
114 }
115
116 /*
117 * We want to know the total length (formatted area and
118 * strings) before decoding to make sure we won't run off the
119 * table in dmi_decode or dmi_string
120 */
121 data += dm->length;
122 while ((data - buf < dmi_len - 1) && (data[0] || data[1]))
123 data++;
124 if (data - buf < dmi_len - 1)
125 decode(dm, private_data);
126
127 data += 2;
128 i++;
129
130 /*
131 * 7.45 End-of-Table (Type 127) [SMBIOS reference spec v3.0.0]
132 * For tables behind a 64-bit entry point, we have no item
133 * count and no exact table length, so stop on end-of-table
134 * marker. For tables behind a 32-bit entry point, we have
135 * seen OEM structures behind the end-of-table marker on
136 * some systems, so don't trust it.
137 */
138 if (!dmi_num && dm->type == DMI_ENTRY_END_OF_TABLE)
139 break;
140 }
141
142 /* Trim DMI table length if needed */
143 if (dmi_len > data - buf)
144 dmi_len = data - buf;
145}
146
147static phys_addr_t dmi_base;
148
149static int __init dmi_walk_early(void (*decode)(const struct dmi_header *,
150 void *))
151{
152 u8 *buf;
153 u32 orig_dmi_len = dmi_len;
154
155 buf = dmi_early_remap(dmi_base, orig_dmi_len);
156 if (buf == NULL)
157 return -ENOMEM;
158
159 dmi_decode_table(buf, decode, NULL);
160
161 add_device_randomness(buf, dmi_len);
162
163 dmi_early_unmap(buf, orig_dmi_len);
164 return 0;
165}
166
167static int __init dmi_checksum(const u8 *buf, u8 len)
168{
169 u8 sum = 0;
170 int a;
171
172 for (a = 0; a < len; a++)
173 sum += buf[a];
174
175 return sum == 0;
176}
177
178static const char *dmi_ident[DMI_STRING_MAX];
179static LIST_HEAD(dmi_devices);
180int dmi_available;
181EXPORT_SYMBOL_GPL(dmi_available);
182
183/*
184 * Save a DMI string
185 */
186static void __init dmi_save_ident(const struct dmi_header *dm, int slot,
187 int string)
188{
189 const char *d = (const char *) dm;
190 const char *p;
191
192 if (dmi_ident[slot] || dm->length <= string)
193 return;
194
195 p = dmi_string(dm, d[string]);
196 if (p == NULL)
197 return;
198
199 dmi_ident[slot] = p;
200}
201
202static void __init dmi_save_release(const struct dmi_header *dm, int slot,
203 int index)
204{
205 const u8 *minor, *major;
206 char *s;
207
208 /* If the table doesn't have the field, let's return */
209 if (dmi_ident[slot] || dm->length < index)
210 return;
211
212 minor = (u8 *) dm + index;
213 major = (u8 *) dm + index - 1;
214
215 /* As per the spec, if the system doesn't support this field,
216 * the value is FF
217 */
218 if (*major == 0xFF && *minor == 0xFF)
219 return;
220
221 s = dmi_alloc(8);
222 if (!s)
223 return;
224
225 sprintf(s, "%u.%u", *major, *minor);
226
227 dmi_ident[slot] = s;
228}
229
230static void __init dmi_save_uuid(const struct dmi_header *dm, int slot,
231 int index)
232{
233 const u8 *d;
234 char *s;
235 int is_ff = 1, is_00 = 1, i;
236
237 if (dmi_ident[slot] || dm->length < index + 16)
238 return;
239
240 d = (u8 *) dm + index;
241 for (i = 0; i < 16 && (is_ff || is_00); i++) {
242 if (d[i] != 0x00)
243 is_00 = 0;
244 if (d[i] != 0xFF)
245 is_ff = 0;
246 }
247
248 if (is_ff || is_00)
249 return;
250
251 s = dmi_alloc(16*2+4+1);
252 if (!s)
253 return;
254
255 /*
256 * As of version 2.6 of the SMBIOS specification, the first 3 fields of
257 * the UUID are supposed to be little-endian encoded. The specification
258 * says that this is the defacto standard.
259 */
260 if (dmi_ver >= 0x020600)
261 sprintf(s, "%pUl", d);
262 else
263 sprintf(s, "%pUb", d);
264
265 dmi_ident[slot] = s;
266}
267
268static void __init dmi_save_type(const struct dmi_header *dm, int slot,
269 int index)
270{
271 const u8 *d;
272 char *s;
273
274 if (dmi_ident[slot] || dm->length <= index)
275 return;
276
277 s = dmi_alloc(4);
278 if (!s)
279 return;
280
281 d = (u8 *) dm + index;
282 sprintf(s, "%u", *d & 0x7F);
283 dmi_ident[slot] = s;
284}
285
286static void __init dmi_save_one_device(int type, const char *name)
287{
288 struct dmi_device *dev;
289
290 /* No duplicate device */
291 if (dmi_find_device(type, name, NULL))
292 return;
293
294 dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
295 if (!dev)
296 return;
297
298 dev->type = type;
299 strcpy((char *)(dev + 1), name);
300 dev->name = (char *)(dev + 1);
301 dev->device_data = NULL;
302 list_add(&dev->list, &dmi_devices);
303}
304
305static void __init dmi_save_devices(const struct dmi_header *dm)
306{
307 int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
308
309 for (i = 0; i < count; i++) {
310 const char *d = (char *)(dm + 1) + (i * 2);
311
312 /* Skip disabled device */
313 if ((*d & 0x80) == 0)
314 continue;
315
316 dmi_save_one_device(*d & 0x7f, dmi_string_nosave(dm, *(d + 1)));
317 }
318}
319
320static void __init dmi_save_oem_strings_devices(const struct dmi_header *dm)
321{
322 int i, count;
323 struct dmi_device *dev;
324
325 if (dm->length < 0x05)
326 return;
327
328 count = *(u8 *)(dm + 1);
329 for (i = 1; i <= count; i++) {
330 const char *devname = dmi_string(dm, i);
331
332 if (devname == dmi_empty_string)
333 continue;
334
335 dev = dmi_alloc(sizeof(*dev));
336 if (!dev)
337 break;
338
339 dev->type = DMI_DEV_TYPE_OEM_STRING;
340 dev->name = devname;
341 dev->device_data = NULL;
342
343 list_add(&dev->list, &dmi_devices);
344 }
345}
346
347static void __init dmi_save_ipmi_device(const struct dmi_header *dm)
348{
349 struct dmi_device *dev;
350 void *data;
351
352 data = dmi_alloc(dm->length);
353 if (data == NULL)
354 return;
355
356 memcpy(data, dm, dm->length);
357
358 dev = dmi_alloc(sizeof(*dev));
359 if (!dev)
360 return;
361
362 dev->type = DMI_DEV_TYPE_IPMI;
363 dev->name = "IPMI controller";
364 dev->device_data = data;
365
366 list_add_tail(&dev->list, &dmi_devices);
367}
368
369static void __init dmi_save_dev_pciaddr(int instance, int segment, int bus,
370 int devfn, const char *name, int type)
371{
372 struct dmi_dev_onboard *dev;
373
374 /* Ignore invalid values */
375 if (type == DMI_DEV_TYPE_DEV_SLOT &&
376 segment == 0xFFFF && bus == 0xFF && devfn == 0xFF)
377 return;
378
379 dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
380 if (!dev)
381 return;
382
383 dev->instance = instance;
384 dev->segment = segment;
385 dev->bus = bus;
386 dev->devfn = devfn;
387
388 strcpy((char *)&dev[1], name);
389 dev->dev.type = type;
390 dev->dev.name = (char *)&dev[1];
391 dev->dev.device_data = dev;
392
393 list_add(&dev->dev.list, &dmi_devices);
394}
395
396static void __init dmi_save_extended_devices(const struct dmi_header *dm)
397{
398 const char *name;
399 const u8 *d = (u8 *)dm;
400
401 if (dm->length < 0x0B)
402 return;
403
404 /* Skip disabled device */
405 if ((d[0x5] & 0x80) == 0)
406 return;
407
408 name = dmi_string_nosave(dm, d[0x4]);
409 dmi_save_dev_pciaddr(d[0x6], *(u16 *)(d + 0x7), d[0x9], d[0xA], name,
410 DMI_DEV_TYPE_DEV_ONBOARD);
411 dmi_save_one_device(d[0x5] & 0x7f, name);
412}
413
414static void __init dmi_save_system_slot(const struct dmi_header *dm)
415{
416 const u8 *d = (u8 *)dm;
417
418 /* Need SMBIOS 2.6+ structure */
419 if (dm->length < 0x11)
420 return;
421 dmi_save_dev_pciaddr(*(u16 *)(d + 0x9), *(u16 *)(d + 0xD), d[0xF],
422 d[0x10], dmi_string_nosave(dm, d[0x4]),
423 DMI_DEV_TYPE_DEV_SLOT);
424}
425
426static void __init count_mem_devices(const struct dmi_header *dm, void *v)
427{
428 if (dm->type != DMI_ENTRY_MEM_DEVICE)
429 return;
430 dmi_memdev_nr++;
431}
432
433static void __init save_mem_devices(const struct dmi_header *dm, void *v)
434{
435 const char *d = (const char *)dm;
436 static int nr;
437 u64 bytes;
438 u16 size;
439
440 if (dm->type != DMI_ENTRY_MEM_DEVICE || dm->length < 0x13)
441 return;
442 if (nr >= dmi_memdev_nr) {
443 pr_warn(FW_BUG "Too many DIMM entries in SMBIOS table\n");
444 return;
445 }
446 dmi_memdev[nr].handle = get_unaligned(&dm->handle);
447 dmi_memdev[nr].device = dmi_string(dm, d[0x10]);
448 dmi_memdev[nr].bank = dmi_string(dm, d[0x11]);
449 dmi_memdev[nr].type = d[0x12];
450
451 size = get_unaligned((u16 *)&d[0xC]);
452 if (size == 0)
453 bytes = 0;
454 else if (size == 0xffff)
455 bytes = ~0ull;
456 else if (size & 0x8000)
457 bytes = (u64)(size & 0x7fff) << 10;
458 else if (size != 0x7fff || dm->length < 0x20)
459 bytes = (u64)size << 20;
460 else
461 bytes = (u64)get_unaligned((u32 *)&d[0x1C]) << 20;
462
463 if (bytes)
464 dmi_memdev_populated_nr++;
465
466 dmi_memdev[nr].size = bytes;
467 nr++;
468}
469
470static void __init dmi_memdev_walk(void)
471{
472 if (dmi_walk_early(count_mem_devices) == 0 && dmi_memdev_nr) {
473 dmi_memdev = dmi_alloc(sizeof(*dmi_memdev) * dmi_memdev_nr);
474 if (dmi_memdev)
475 dmi_walk_early(save_mem_devices);
476 }
477}
478
479/*
480 * Process a DMI table entry. Right now all we care about are the BIOS
481 * and machine entries. For 2.5 we should pull the smbus controller info
482 * out of here.
483 */
484static void __init dmi_decode(const struct dmi_header *dm, void *dummy)
485{
486 switch (dm->type) {
487 case 0: /* BIOS Information */
488 dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
489 dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
490 dmi_save_ident(dm, DMI_BIOS_DATE, 8);
491 dmi_save_release(dm, DMI_BIOS_RELEASE, 21);
492 dmi_save_release(dm, DMI_EC_FIRMWARE_RELEASE, 23);
493 break;
494 case 1: /* System Information */
495 dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
496 dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
497 dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
498 dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
499 dmi_save_uuid(dm, DMI_PRODUCT_UUID, 8);
500 dmi_save_ident(dm, DMI_PRODUCT_SKU, 25);
501 dmi_save_ident(dm, DMI_PRODUCT_FAMILY, 26);
502 break;
503 case 2: /* Base Board Information */
504 dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
505 dmi_save_ident(dm, DMI_BOARD_NAME, 5);
506 dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
507 dmi_save_ident(dm, DMI_BOARD_SERIAL, 7);
508 dmi_save_ident(dm, DMI_BOARD_ASSET_TAG, 8);
509 break;
510 case 3: /* Chassis Information */
511 dmi_save_ident(dm, DMI_CHASSIS_VENDOR, 4);
512 dmi_save_type(dm, DMI_CHASSIS_TYPE, 5);
513 dmi_save_ident(dm, DMI_CHASSIS_VERSION, 6);
514 dmi_save_ident(dm, DMI_CHASSIS_SERIAL, 7);
515 dmi_save_ident(dm, DMI_CHASSIS_ASSET_TAG, 8);
516 break;
517 case 9: /* System Slots */
518 dmi_save_system_slot(dm);
519 break;
520 case 10: /* Onboard Devices Information */
521 dmi_save_devices(dm);
522 break;
523 case 11: /* OEM Strings */
524 dmi_save_oem_strings_devices(dm);
525 break;
526 case 38: /* IPMI Device Information */
527 dmi_save_ipmi_device(dm);
528 break;
529 case 41: /* Onboard Devices Extended Information */
530 dmi_save_extended_devices(dm);
531 }
532}
533
534static int __init print_filtered(char *buf, size_t len, const char *info)
535{
536 int c = 0;
537 const char *p;
538
539 if (!info)
540 return c;
541
542 for (p = info; *p; p++)
543 if (isprint(*p))
544 c += scnprintf(buf + c, len - c, "%c", *p);
545 else
546 c += scnprintf(buf + c, len - c, "\\x%02x", *p & 0xff);
547 return c;
548}
549
550static void __init dmi_format_ids(char *buf, size_t len)
551{
552 int c = 0;
553 const char *board; /* Board Name is optional */
554
555 c += print_filtered(buf + c, len - c,
556 dmi_get_system_info(DMI_SYS_VENDOR));
557 c += scnprintf(buf + c, len - c, " ");
558 c += print_filtered(buf + c, len - c,
559 dmi_get_system_info(DMI_PRODUCT_NAME));
560
561 board = dmi_get_system_info(DMI_BOARD_NAME);
562 if (board) {
563 c += scnprintf(buf + c, len - c, "/");
564 c += print_filtered(buf + c, len - c, board);
565 }
566 c += scnprintf(buf + c, len - c, ", BIOS ");
567 c += print_filtered(buf + c, len - c,
568 dmi_get_system_info(DMI_BIOS_VERSION));
569 c += scnprintf(buf + c, len - c, " ");
570 c += print_filtered(buf + c, len - c,
571 dmi_get_system_info(DMI_BIOS_DATE));
572}
573
574/*
575 * Check for DMI/SMBIOS headers in the system firmware image. Any
576 * SMBIOS header must start 16 bytes before the DMI header, so take a
577 * 32 byte buffer and check for DMI at offset 16 and SMBIOS at offset
578 * 0. If the DMI header is present, set dmi_ver accordingly (SMBIOS
579 * takes precedence) and return 0. Otherwise return 1.
580 */
581static int __init dmi_present(const u8 *buf)
582{
583 u32 smbios_ver;
584
585 /*
586 * The size of this structure is 31 bytes, but we also accept value
587 * 30 due to a mistake in SMBIOS specification version 2.1.
588 */
589 if (memcmp(buf, "_SM_", 4) == 0 &&
590 buf[5] >= 30 && buf[5] <= 32 &&
591 dmi_checksum(buf, buf[5])) {
592 smbios_ver = get_unaligned_be16(buf + 6);
593 smbios_entry_point_size = buf[5];
594 memcpy(smbios_entry_point, buf, smbios_entry_point_size);
595
596 /* Some BIOS report weird SMBIOS version, fix that up */
597 switch (smbios_ver) {
598 case 0x021F:
599 case 0x0221:
600 pr_debug("SMBIOS version fixup (2.%d->2.%d)\n",
601 smbios_ver & 0xFF, 3);
602 smbios_ver = 0x0203;
603 break;
604 case 0x0233:
605 pr_debug("SMBIOS version fixup (2.%d->2.%d)\n", 51, 6);
606 smbios_ver = 0x0206;
607 break;
608 }
609 } else {
610 smbios_ver = 0;
611 }
612
613 buf += 16;
614
615 if (memcmp(buf, "_DMI_", 5) == 0 && dmi_checksum(buf, 15)) {
616 if (smbios_ver)
617 dmi_ver = smbios_ver;
618 else
619 dmi_ver = (buf[14] & 0xF0) << 4 | (buf[14] & 0x0F);
620 dmi_ver <<= 8;
621 dmi_num = get_unaligned_le16(buf + 12);
622 dmi_len = get_unaligned_le16(buf + 6);
623 dmi_base = get_unaligned_le32(buf + 8);
624
625 if (dmi_walk_early(dmi_decode) == 0) {
626 if (smbios_ver) {
627 pr_info("SMBIOS %d.%d present.\n",
628 dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
629 } else {
630 smbios_entry_point_size = 15;
631 memcpy(smbios_entry_point, buf,
632 smbios_entry_point_size);
633 pr_info("Legacy DMI %d.%d present.\n",
634 dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
635 }
636 dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
637 pr_info("DMI: %s\n", dmi_ids_string);
638 return 0;
639 }
640 }
641
642 return 1;
643}
644
645/*
646 * Check for the SMBIOS 3.0 64-bit entry point signature. Unlike the legacy
647 * 32-bit entry point, there is no embedded DMI header (_DMI_) in here.
648 */
649static int __init dmi_smbios3_present(const u8 *buf)
650{
651 if (memcmp(buf, "_SM3_", 5) == 0 &&
652 buf[6] >= 24 && buf[6] <= 32 &&
653 dmi_checksum(buf, buf[6])) {
654 dmi_ver = get_unaligned_be24(buf + 7);
655 dmi_num = 0; /* No longer specified */
656 dmi_len = get_unaligned_le32(buf + 12);
657 dmi_base = get_unaligned_le64(buf + 16);
658 smbios_entry_point_size = buf[6];
659 memcpy(smbios_entry_point, buf, smbios_entry_point_size);
660
661 if (dmi_walk_early(dmi_decode) == 0) {
662 pr_info("SMBIOS %d.%d.%d present.\n",
663 dmi_ver >> 16, (dmi_ver >> 8) & 0xFF,
664 dmi_ver & 0xFF);
665 dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
666 pr_info("DMI: %s\n", dmi_ids_string);
667 return 0;
668 }
669 }
670 return 1;
671}
672
673static void __init dmi_scan_machine(void)
674{
675 char __iomem *p, *q;
676 char buf[32];
677
678 if (efi_enabled(EFI_CONFIG_TABLES)) {
679 /*
680 * According to the DMTF SMBIOS reference spec v3.0.0, it is
681 * allowed to define both the 64-bit entry point (smbios3) and
682 * the 32-bit entry point (smbios), in which case they should
683 * either both point to the same SMBIOS structure table, or the
684 * table pointed to by the 64-bit entry point should contain a
685 * superset of the table contents pointed to by the 32-bit entry
686 * point (section 5.2)
687 * This implies that the 64-bit entry point should have
688 * precedence if it is defined and supported by the OS. If we
689 * have the 64-bit entry point, but fail to decode it, fall
690 * back to the legacy one (if available)
691 */
692 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) {
693 p = dmi_early_remap(efi.smbios3, 32);
694 if (p == NULL)
695 goto error;
696 memcpy_fromio(buf, p, 32);
697 dmi_early_unmap(p, 32);
698
699 if (!dmi_smbios3_present(buf)) {
700 dmi_available = 1;
701 return;
702 }
703 }
704 if (efi.smbios == EFI_INVALID_TABLE_ADDR)
705 goto error;
706
707 /* This is called as a core_initcall() because it isn't
708 * needed during early boot. This also means we can
709 * iounmap the space when we're done with it.
710 */
711 p = dmi_early_remap(efi.smbios, 32);
712 if (p == NULL)
713 goto error;
714 memcpy_fromio(buf, p, 32);
715 dmi_early_unmap(p, 32);
716
717 if (!dmi_present(buf)) {
718 dmi_available = 1;
719 return;
720 }
721 } else if (IS_ENABLED(CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK)) {
722 p = dmi_early_remap(SMBIOS_ENTRY_POINT_SCAN_START, 0x10000);
723 if (p == NULL)
724 goto error;
725
726 /*
727 * Same logic as above, look for a 64-bit entry point
728 * first, and if not found, fall back to 32-bit entry point.
729 */
730 memcpy_fromio(buf, p, 16);
731 for (q = p + 16; q < p + 0x10000; q += 16) {
732 memcpy_fromio(buf + 16, q, 16);
733 if (!dmi_smbios3_present(buf)) {
734 dmi_available = 1;
735 dmi_early_unmap(p, 0x10000);
736 return;
737 }
738 memcpy(buf, buf + 16, 16);
739 }
740
741 /*
742 * Iterate over all possible DMI header addresses q.
743 * Maintain the 32 bytes around q in buf. On the
744 * first iteration, substitute zero for the
745 * out-of-range bytes so there is no chance of falsely
746 * detecting an SMBIOS header.
747 */
748 memset(buf, 0, 16);
749 for (q = p; q < p + 0x10000; q += 16) {
750 memcpy_fromio(buf + 16, q, 16);
751 if (!dmi_present(buf)) {
752 dmi_available = 1;
753 dmi_early_unmap(p, 0x10000);
754 return;
755 }
756 memcpy(buf, buf + 16, 16);
757 }
758 dmi_early_unmap(p, 0x10000);
759 }
760 error:
761 pr_info("DMI not present or invalid.\n");
762}
763
764static BIN_ATTR_SIMPLE_ADMIN_RO(smbios_entry_point);
765static BIN_ATTR_SIMPLE_ADMIN_RO(DMI);
766
767static int __init dmi_init(void)
768{
769 struct kobject *tables_kobj;
770 u8 *dmi_table;
771 int ret = -ENOMEM;
772
773 if (!dmi_available)
774 return 0;
775
776 /*
777 * Set up dmi directory at /sys/firmware/dmi. This entry should stay
778 * even after farther error, as it can be used by other modules like
779 * dmi-sysfs.
780 */
781 dmi_kobj = kobject_create_and_add("dmi", firmware_kobj);
782 if (!dmi_kobj)
783 goto err;
784
785 tables_kobj = kobject_create_and_add("tables", dmi_kobj);
786 if (!tables_kobj)
787 goto err;
788
789 dmi_table = dmi_remap(dmi_base, dmi_len);
790 if (!dmi_table)
791 goto err_tables;
792
793 bin_attr_smbios_entry_point.size = smbios_entry_point_size;
794 bin_attr_smbios_entry_point.private = smbios_entry_point;
795 ret = sysfs_create_bin_file(tables_kobj, &bin_attr_smbios_entry_point);
796 if (ret)
797 goto err_unmap;
798
799 bin_attr_DMI.size = dmi_len;
800 bin_attr_DMI.private = dmi_table;
801 ret = sysfs_create_bin_file(tables_kobj, &bin_attr_DMI);
802 if (!ret)
803 return 0;
804
805 sysfs_remove_bin_file(tables_kobj,
806 &bin_attr_smbios_entry_point);
807 err_unmap:
808 dmi_unmap(dmi_table);
809 err_tables:
810 kobject_del(tables_kobj);
811 kobject_put(tables_kobj);
812 err:
813 pr_err("dmi: Firmware registration failed.\n");
814
815 return ret;
816}
817subsys_initcall(dmi_init);
818
819/**
820 * dmi_setup - scan and setup DMI system information
821 *
822 * Scan the DMI system information. This setups DMI identifiers
823 * (dmi_system_id) for printing it out on task dumps and prepares
824 * DIMM entry information (dmi_memdev_info) from the SMBIOS table
825 * for using this when reporting memory errors.
826 */
827void __init dmi_setup(void)
828{
829 dmi_scan_machine();
830 if (!dmi_available)
831 return;
832
833 dmi_memdev_walk();
834 pr_info("DMI: Memory slots populated: %d/%d\n",
835 dmi_memdev_populated_nr, dmi_memdev_nr);
836 dump_stack_set_arch_desc("%s", dmi_ids_string);
837}
838
839/**
840 * dmi_matches - check if dmi_system_id structure matches system DMI data
841 * @dmi: pointer to the dmi_system_id structure to check
842 */
843static bool dmi_matches(const struct dmi_system_id *dmi)
844{
845 int i;
846
847 for (i = 0; i < ARRAY_SIZE(dmi->matches); i++) {
848 int s = dmi->matches[i].slot;
849 if (s == DMI_NONE)
850 break;
851 if (s == DMI_OEM_STRING) {
852 /* DMI_OEM_STRING must be exact match */
853 const struct dmi_device *valid;
854
855 valid = dmi_find_device(DMI_DEV_TYPE_OEM_STRING,
856 dmi->matches[i].substr, NULL);
857 if (valid)
858 continue;
859 } else if (dmi_ident[s]) {
860 if (dmi->matches[i].exact_match) {
861 if (!strcmp(dmi_ident[s],
862 dmi->matches[i].substr))
863 continue;
864 } else {
865 if (strstr(dmi_ident[s],
866 dmi->matches[i].substr))
867 continue;
868 }
869 }
870
871 /* No match */
872 return false;
873 }
874 return true;
875}
876
877/**
878 * dmi_is_end_of_table - check for end-of-table marker
879 * @dmi: pointer to the dmi_system_id structure to check
880 */
881static bool dmi_is_end_of_table(const struct dmi_system_id *dmi)
882{
883 return dmi->matches[0].slot == DMI_NONE;
884}
885
886/**
887 * dmi_check_system - check system DMI data
888 * @list: array of dmi_system_id structures to match against
889 * All non-null elements of the list must match
890 * their slot's (field index's) data (i.e., each
891 * list string must be a substring of the specified
892 * DMI slot's string data) to be considered a
893 * successful match.
894 *
895 * Walk the blacklist table running matching functions until someone
896 * returns non zero or we hit the end. Callback function is called for
897 * each successful match. Returns the number of matches.
898 *
899 * dmi_setup must be called before this function is called.
900 */
901int dmi_check_system(const struct dmi_system_id *list)
902{
903 int count = 0;
904 const struct dmi_system_id *d;
905
906 for (d = list; !dmi_is_end_of_table(d); d++)
907 if (dmi_matches(d)) {
908 count++;
909 if (d->callback && d->callback(d))
910 break;
911 }
912
913 return count;
914}
915EXPORT_SYMBOL(dmi_check_system);
916
917/**
918 * dmi_first_match - find dmi_system_id structure matching system DMI data
919 * @list: array of dmi_system_id structures to match against
920 * All non-null elements of the list must match
921 * their slot's (field index's) data (i.e., each
922 * list string must be a substring of the specified
923 * DMI slot's string data) to be considered a
924 * successful match.
925 *
926 * Walk the blacklist table until the first match is found. Return the
927 * pointer to the matching entry or NULL if there's no match.
928 *
929 * dmi_setup must be called before this function is called.
930 */
931const struct dmi_system_id *dmi_first_match(const struct dmi_system_id *list)
932{
933 const struct dmi_system_id *d;
934
935 for (d = list; !dmi_is_end_of_table(d); d++)
936 if (dmi_matches(d))
937 return d;
938
939 return NULL;
940}
941EXPORT_SYMBOL(dmi_first_match);
942
943/**
944 * dmi_get_system_info - return DMI data value
945 * @field: data index (see enum dmi_field)
946 *
947 * Returns one DMI data value, can be used to perform
948 * complex DMI data checks.
949 */
950const char *dmi_get_system_info(int field)
951{
952 return dmi_ident[field];
953}
954EXPORT_SYMBOL(dmi_get_system_info);
955
956/**
957 * dmi_name_in_serial - Check if string is in the DMI product serial information
958 * @str: string to check for
959 */
960int dmi_name_in_serial(const char *str)
961{
962 int f = DMI_PRODUCT_SERIAL;
963 if (dmi_ident[f] && strstr(dmi_ident[f], str))
964 return 1;
965 return 0;
966}
967
968/**
969 * dmi_name_in_vendors - Check if string is in the DMI system or board vendor name
970 * @str: Case sensitive Name
971 */
972int dmi_name_in_vendors(const char *str)
973{
974 static int fields[] = { DMI_SYS_VENDOR, DMI_BOARD_VENDOR, DMI_NONE };
975 int i;
976 for (i = 0; fields[i] != DMI_NONE; i++) {
977 int f = fields[i];
978 if (dmi_ident[f] && strstr(dmi_ident[f], str))
979 return 1;
980 }
981 return 0;
982}
983EXPORT_SYMBOL(dmi_name_in_vendors);
984
985/**
986 * dmi_find_device - find onboard device by type/name
987 * @type: device type or %DMI_DEV_TYPE_ANY to match all device types
988 * @name: device name string or %NULL to match all
989 * @from: previous device found in search, or %NULL for new search.
990 *
991 * Iterates through the list of known onboard devices. If a device is
992 * found with a matching @type and @name, a pointer to its device
993 * structure is returned. Otherwise, %NULL is returned.
994 * A new search is initiated by passing %NULL as the @from argument.
995 * If @from is not %NULL, searches continue from next device.
996 */
997const struct dmi_device *dmi_find_device(int type, const char *name,
998 const struct dmi_device *from)
999{
1000 const struct list_head *head = from ? &from->list : &dmi_devices;
1001 struct list_head *d;
1002
1003 for (d = head->next; d != &dmi_devices; d = d->next) {
1004 const struct dmi_device *dev =
1005 list_entry(d, struct dmi_device, list);
1006
1007 if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
1008 ((name == NULL) || (strcmp(dev->name, name) == 0)))
1009 return dev;
1010 }
1011
1012 return NULL;
1013}
1014EXPORT_SYMBOL(dmi_find_device);
1015
1016/**
1017 * dmi_get_date - parse a DMI date
1018 * @field: data index (see enum dmi_field)
1019 * @yearp: optional out parameter for the year
1020 * @monthp: optional out parameter for the month
1021 * @dayp: optional out parameter for the day
1022 *
1023 * The date field is assumed to be in the form resembling
1024 * [mm[/dd]]/yy[yy] and the result is stored in the out
1025 * parameters any or all of which can be omitted.
1026 *
1027 * If the field doesn't exist, all out parameters are set to zero
1028 * and false is returned. Otherwise, true is returned with any
1029 * invalid part of date set to zero.
1030 *
1031 * On return, year, month and day are guaranteed to be in the
1032 * range of [0,9999], [0,12] and [0,31] respectively.
1033 */
1034bool dmi_get_date(int field, int *yearp, int *monthp, int *dayp)
1035{
1036 int year = 0, month = 0, day = 0;
1037 bool exists;
1038 const char *s, *y;
1039 char *e;
1040
1041 s = dmi_get_system_info(field);
1042 exists = s;
1043 if (!exists)
1044 goto out;
1045
1046 /*
1047 * Determine year first. We assume the date string resembles
1048 * mm/dd/yy[yy] but the original code extracted only the year
1049 * from the end. Keep the behavior in the spirit of no
1050 * surprises.
1051 */
1052 y = strrchr(s, '/');
1053 if (!y)
1054 goto out;
1055
1056 y++;
1057 year = simple_strtoul(y, &e, 10);
1058 if (y != e && year < 100) { /* 2-digit year */
1059 year += 1900;
1060 if (year < 1996) /* no dates < spec 1.0 */
1061 year += 100;
1062 }
1063 if (year > 9999) /* year should fit in %04d */
1064 year = 0;
1065
1066 /* parse the mm and dd */
1067 month = simple_strtoul(s, &e, 10);
1068 if (s == e || *e != '/' || !month || month > 12) {
1069 month = 0;
1070 goto out;
1071 }
1072
1073 s = e + 1;
1074 day = simple_strtoul(s, &e, 10);
1075 if (s == y || s == e || *e != '/' || day > 31)
1076 day = 0;
1077out:
1078 if (yearp)
1079 *yearp = year;
1080 if (monthp)
1081 *monthp = month;
1082 if (dayp)
1083 *dayp = day;
1084 return exists;
1085}
1086EXPORT_SYMBOL(dmi_get_date);
1087
1088/**
1089 * dmi_get_bios_year - get a year out of DMI_BIOS_DATE field
1090 *
1091 * Returns year on success, -ENXIO if DMI is not selected,
1092 * or a different negative error code if DMI field is not present
1093 * or not parseable.
1094 */
1095int dmi_get_bios_year(void)
1096{
1097 bool exists;
1098 int year;
1099
1100 exists = dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL);
1101 if (!exists)
1102 return -ENODATA;
1103
1104 return year ? year : -ERANGE;
1105}
1106EXPORT_SYMBOL(dmi_get_bios_year);
1107
1108/**
1109 * dmi_walk - Walk the DMI table and get called back for every record
1110 * @decode: Callback function
1111 * @private_data: Private data to be passed to the callback function
1112 *
1113 * Returns 0 on success, -ENXIO if DMI is not selected or not present,
1114 * or a different negative error code if DMI walking fails.
1115 */
1116int dmi_walk(void (*decode)(const struct dmi_header *, void *),
1117 void *private_data)
1118{
1119 u8 *buf;
1120
1121 if (!dmi_available)
1122 return -ENXIO;
1123
1124 buf = dmi_remap(dmi_base, dmi_len);
1125 if (buf == NULL)
1126 return -ENOMEM;
1127
1128 dmi_decode_table(buf, decode, private_data);
1129
1130 dmi_unmap(buf);
1131 return 0;
1132}
1133EXPORT_SYMBOL_GPL(dmi_walk);
1134
1135/**
1136 * dmi_match - compare a string to the dmi field (if exists)
1137 * @f: DMI field identifier
1138 * @str: string to compare the DMI field to
1139 *
1140 * Returns true if the requested field equals to the str (including NULL).
1141 */
1142bool dmi_match(enum dmi_field f, const char *str)
1143{
1144 const char *info = dmi_get_system_info(f);
1145
1146 if (info == NULL || str == NULL)
1147 return info == str;
1148
1149 return !strcmp(info, str);
1150}
1151EXPORT_SYMBOL_GPL(dmi_match);
1152
1153void dmi_memdev_name(u16 handle, const char **bank, const char **device)
1154{
1155 int n;
1156
1157 if (dmi_memdev == NULL)
1158 return;
1159
1160 for (n = 0; n < dmi_memdev_nr; n++) {
1161 if (handle == dmi_memdev[n].handle) {
1162 *bank = dmi_memdev[n].bank;
1163 *device = dmi_memdev[n].device;
1164 break;
1165 }
1166 }
1167}
1168EXPORT_SYMBOL_GPL(dmi_memdev_name);
1169
1170u64 dmi_memdev_size(u16 handle)
1171{
1172 int n;
1173
1174 if (dmi_memdev) {
1175 for (n = 0; n < dmi_memdev_nr; n++) {
1176 if (handle == dmi_memdev[n].handle)
1177 return dmi_memdev[n].size;
1178 }
1179 }
1180 return ~0ull;
1181}
1182EXPORT_SYMBOL_GPL(dmi_memdev_size);
1183
1184/**
1185 * dmi_memdev_type - get the memory type
1186 * @handle: DMI structure handle
1187 *
1188 * Return the DMI memory type of the module in the slot associated with the
1189 * given DMI handle, or 0x0 if no such DMI handle exists.
1190 */
1191u8 dmi_memdev_type(u16 handle)
1192{
1193 int n;
1194
1195 if (dmi_memdev) {
1196 for (n = 0; n < dmi_memdev_nr; n++) {
1197 if (handle == dmi_memdev[n].handle)
1198 return dmi_memdev[n].type;
1199 }
1200 }
1201 return 0x0; /* Not a valid value */
1202}
1203EXPORT_SYMBOL_GPL(dmi_memdev_type);
1204
1205/**
1206 * dmi_memdev_handle - get the DMI handle of a memory slot
1207 * @slot: slot number
1208 *
1209 * Return the DMI handle associated with a given memory slot, or %0xFFFF
1210 * if there is no such slot.
1211 */
1212u16 dmi_memdev_handle(int slot)
1213{
1214 if (dmi_memdev && slot >= 0 && slot < dmi_memdev_nr)
1215 return dmi_memdev[slot].handle;
1216
1217 return 0xffff; /* Not a valid value */
1218}
1219EXPORT_SYMBOL_GPL(dmi_memdev_handle);
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
14struct kobject *dmi_kobj;
15EXPORT_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 */
22static const char dmi_empty_string[] = "";
23
24static u32 dmi_ver __initdata;
25static u32 dmi_len;
26static u16 dmi_num;
27static u8 smbios_entry_point[32];
28static int smbios_entry_point_size;
29
30/* DMI system identification string used during boot */
31static char dmi_ids_string[128] __initdata;
32
33static struct dmi_memdev_info {
34 const char *device;
35 const char *bank;
36 u64 size; /* bytes */
37 u16 handle;
38} *dmi_memdev;
39static int dmi_memdev_nr;
40
41static 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
61static 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 */
82static 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
130static phys_addr_t dmi_base;
131
132static 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
150static 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
161static const char *dmi_ident[DMI_STRING_MAX];
162static LIST_HEAD(dmi_devices);
163int dmi_available;
164
165/*
166 * Save a DMI string
167 */
168static 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
184static 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
222static 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
240static 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
259static 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
274static 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
301static 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
323static 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
350static 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
368static 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
380static 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
387static 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
420static 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 */
434static 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
482static 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
498static 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 */
529static 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 */
592static 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
615static 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
706static 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
714static BIN_ATTR(smbios_entry_point, S_IRUSR, raw_table_read, NULL, 0);
715static BIN_ATTR(DMI, S_IRUSR, raw_table_read, NULL, 0);
716
717static 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}
767subsys_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 */
777void __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 */
791static 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 */
829static 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 */
849int 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}
863EXPORT_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 */
879const 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}
889EXPORT_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 */
898const char *dmi_get_system_info(int field)
899{
900 return dmi_ident[field];
901}
902EXPORT_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 */
908int 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 */
920int 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}
931EXPORT_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 */
945const 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}
962EXPORT_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 */
982bool 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;
1025out:
1026 if (yearp)
1027 *yearp = year;
1028 if (monthp)
1029 *monthp = month;
1030 if (dayp)
1031 *dayp = day;
1032 return exists;
1033}
1034EXPORT_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 */
1043int 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}
1054EXPORT_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 */
1064int 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}
1081EXPORT_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 */
1090bool 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}
1099EXPORT_SYMBOL_GPL(dmi_match);
1100
1101void 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}
1116EXPORT_SYMBOL_GPL(dmi_memdev_name);
1117
1118u64 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}
1130EXPORT_SYMBOL_GPL(dmi_memdev_size);