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