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(p: str, q: 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(phys_addr: dmi_base, size: orig_dmi_len);
144 if (buf == NULL)
145 return -ENOMEM;
146
147 dmi_decode_table(buf, decode, NULL);
148
149 add_device_randomness(buf, len: dmi_len);
150
151 dmi_early_unmap(addr: buf, size: 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, s: 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(len: 8);
210 if (!s)
211 return;
212
213 sprintf(buf: s, fmt: "%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(len: 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(buf: s, fmt: "%pUl", d);
250 else
251 sprintf(buf: s, fmt: "%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(len: 4);
266 if (!s)
267 return;
268
269 d = (u8 *) dm + index;
270 sprintf(buf: s, fmt: "%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(len: sizeof(*dev) + strlen(name) + 1);
283 if (!dev)
284 return;
285
286 dev->type = type;
287 strcpy(p: (char *)(dev + 1), q: name);
288 dev->name = (char *)(dev + 1);
289 dev->device_data = NULL;
290 list_add(new: &dev->list, head: &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(type: *d & 0x7f, name: dmi_string_nosave(dm, s: *(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, s: i);
319
320 if (devname == dmi_empty_string)
321 continue;
322
323 dev = dmi_alloc(len: 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(new: &dev->list, head: &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(len: dm->length);
341 if (data == NULL)
342 return;
343
344 memcpy(data, dm, dm->length);
345
346 dev = dmi_alloc(len: 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(new: &dev->list, head: &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(len: 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(p: (char *)&dev[1], q: name);
377 dev->dev.type = type;
378 dev->dev.name = (char *)&dev[1];
379 dev->dev.device_data = dev;
380
381 list_add(new: &dev->dev.list, head: &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, s: d[0x4]);
397 dmi_save_dev_pciaddr(instance: d[0x6], segment: *(u16 *)(d + 0x7), bus: d[0x9], devfn: d[0xA], name,
398 type: DMI_DEV_TYPE_DEV_ONBOARD);
399 dmi_save_one_device(type: 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(instance: *(u16 *)(d + 0x9), segment: *(u16 *)(d + 0xD), bus: d[0xF],
410 devfn: d[0x10], name: dmi_string_nosave(dm, s: d[0x4]),
411 type: 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, s: d[0x10]);
436 dmi_memdev[nr].bank = dmi_string(dm, s: 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(decode: count_mem_devices) == 0 && dmi_memdev_nr) {
458 dmi_memdev = dmi_alloc(len: sizeof(*dmi_memdev) * dmi_memdev_nr);
459 if (dmi_memdev)
460 dmi_walk_early(decode: 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, slot: DMI_BIOS_VENDOR, string: 4);
474 dmi_save_ident(dm, slot: DMI_BIOS_VERSION, string: 5);
475 dmi_save_ident(dm, slot: DMI_BIOS_DATE, string: 8);
476 dmi_save_release(dm, slot: DMI_BIOS_RELEASE, index: 21);
477 dmi_save_release(dm, slot: DMI_EC_FIRMWARE_RELEASE, index: 23);
478 break;
479 case 1: /* System Information */
480 dmi_save_ident(dm, slot: DMI_SYS_VENDOR, string: 4);
481 dmi_save_ident(dm, slot: DMI_PRODUCT_NAME, string: 5);
482 dmi_save_ident(dm, slot: DMI_PRODUCT_VERSION, string: 6);
483 dmi_save_ident(dm, slot: DMI_PRODUCT_SERIAL, string: 7);
484 dmi_save_uuid(dm, slot: DMI_PRODUCT_UUID, index: 8);
485 dmi_save_ident(dm, slot: DMI_PRODUCT_SKU, string: 25);
486 dmi_save_ident(dm, slot: DMI_PRODUCT_FAMILY, string: 26);
487 break;
488 case 2: /* Base Board Information */
489 dmi_save_ident(dm, slot: DMI_BOARD_VENDOR, string: 4);
490 dmi_save_ident(dm, slot: DMI_BOARD_NAME, string: 5);
491 dmi_save_ident(dm, slot: DMI_BOARD_VERSION, string: 6);
492 dmi_save_ident(dm, slot: DMI_BOARD_SERIAL, string: 7);
493 dmi_save_ident(dm, slot: DMI_BOARD_ASSET_TAG, string: 8);
494 break;
495 case 3: /* Chassis Information */
496 dmi_save_ident(dm, slot: DMI_CHASSIS_VENDOR, string: 4);
497 dmi_save_type(dm, slot: DMI_CHASSIS_TYPE, index: 5);
498 dmi_save_ident(dm, slot: DMI_CHASSIS_VERSION, string: 6);
499 dmi_save_ident(dm, slot: DMI_CHASSIS_SERIAL, string: 7);
500 dmi_save_ident(dm, slot: DMI_CHASSIS_ASSET_TAG, string: 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: buf + c, size: len - c, fmt: "%c", *p);
530 else
531 c += scnprintf(buf: buf + c, size: len - c, fmt: "\\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: buf + c, len: len - c,
541 info: dmi_get_system_info(field: DMI_SYS_VENDOR));
542 c += scnprintf(buf: buf + c, size: len - c, fmt: " ");
543 c += print_filtered(buf: buf + c, len: len - c,
544 info: dmi_get_system_info(field: DMI_PRODUCT_NAME));
545
546 board = dmi_get_system_info(field: DMI_BOARD_NAME);
547 if (board) {
548 c += scnprintf(buf: buf + c, size: len - c, fmt: "/");
549 c += print_filtered(buf: buf + c, len: len - c, info: board);
550 }
551 c += scnprintf(buf: buf + c, size: len - c, fmt: ", BIOS ");
552 c += print_filtered(buf: buf + c, len: len - c,
553 info: dmi_get_system_info(field: DMI_BIOS_VERSION));
554 c += scnprintf(buf: buf + c, size: len - c, fmt: " ");
555 c += print_filtered(buf: buf + c, len: len - c,
556 info: dmi_get_system_info(field: 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 /*
571 * The size of this structure is 31 bytes, but we also accept value
572 * 30 due to a mistake in SMBIOS specification version 2.1.
573 */
574 if (memcmp(p: buf, q: "_SM_", size: 4) == 0 &&
575 buf[5] >= 30 && buf[5] <= 32 &&
576 dmi_checksum(buf, len: buf[5])) {
577 smbios_ver = get_unaligned_be16(p: buf + 6);
578 smbios_entry_point_size = buf[5];
579 memcpy(smbios_entry_point, buf, smbios_entry_point_size);
580
581 /* Some BIOS report weird SMBIOS version, fix that up */
582 switch (smbios_ver) {
583 case 0x021F:
584 case 0x0221:
585 pr_debug("SMBIOS version fixup (2.%d->2.%d)\n",
586 smbios_ver & 0xFF, 3);
587 smbios_ver = 0x0203;
588 break;
589 case 0x0233:
590 pr_debug("SMBIOS version fixup (2.%d->2.%d)\n", 51, 6);
591 smbios_ver = 0x0206;
592 break;
593 }
594 } else {
595 smbios_ver = 0;
596 }
597
598 buf += 16;
599
600 if (memcmp(p: buf, q: "_DMI_", size: 5) == 0 && dmi_checksum(buf, len: 15)) {
601 if (smbios_ver)
602 dmi_ver = smbios_ver;
603 else
604 dmi_ver = (buf[14] & 0xF0) << 4 | (buf[14] & 0x0F);
605 dmi_ver <<= 8;
606 dmi_num = get_unaligned_le16(p: buf + 12);
607 dmi_len = get_unaligned_le16(p: buf + 6);
608 dmi_base = get_unaligned_le32(p: buf + 8);
609
610 if (dmi_walk_early(decode: dmi_decode) == 0) {
611 if (smbios_ver) {
612 pr_info("SMBIOS %d.%d present.\n",
613 dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
614 } else {
615 smbios_entry_point_size = 15;
616 memcpy(smbios_entry_point, buf,
617 smbios_entry_point_size);
618 pr_info("Legacy DMI %d.%d present.\n",
619 dmi_ver >> 16, (dmi_ver >> 8) & 0xFF);
620 }
621 dmi_format_ids(buf: dmi_ids_string, len: sizeof(dmi_ids_string));
622 pr_info("DMI: %s\n", dmi_ids_string);
623 return 0;
624 }
625 }
626
627 return 1;
628}
629
630/*
631 * Check for the SMBIOS 3.0 64-bit entry point signature. Unlike the legacy
632 * 32-bit entry point, there is no embedded DMI header (_DMI_) in here.
633 */
634static int __init dmi_smbios3_present(const u8 *buf)
635{
636 if (memcmp(p: buf, q: "_SM3_", size: 5) == 0 &&
637 buf[6] >= 24 && buf[6] <= 32 &&
638 dmi_checksum(buf, len: buf[6])) {
639 dmi_ver = get_unaligned_be24(p: buf + 7);
640 dmi_num = 0; /* No longer specified */
641 dmi_len = get_unaligned_le32(p: buf + 12);
642 dmi_base = get_unaligned_le64(p: buf + 16);
643 smbios_entry_point_size = buf[6];
644 memcpy(smbios_entry_point, buf, smbios_entry_point_size);
645
646 if (dmi_walk_early(decode: dmi_decode) == 0) {
647 pr_info("SMBIOS %d.%d.%d present.\n",
648 dmi_ver >> 16, (dmi_ver >> 8) & 0xFF,
649 dmi_ver & 0xFF);
650 dmi_format_ids(buf: dmi_ids_string, len: sizeof(dmi_ids_string));
651 pr_info("DMI: %s\n", dmi_ids_string);
652 return 0;
653 }
654 }
655 return 1;
656}
657
658static void __init dmi_scan_machine(void)
659{
660 char __iomem *p, *q;
661 char buf[32];
662
663 if (efi_enabled(EFI_CONFIG_TABLES)) {
664 /*
665 * According to the DMTF SMBIOS reference spec v3.0.0, it is
666 * allowed to define both the 64-bit entry point (smbios3) and
667 * the 32-bit entry point (smbios), in which case they should
668 * either both point to the same SMBIOS structure table, or the
669 * table pointed to by the 64-bit entry point should contain a
670 * superset of the table contents pointed to by the 32-bit entry
671 * point (section 5.2)
672 * This implies that the 64-bit entry point should have
673 * precedence if it is defined and supported by the OS. If we
674 * have the 64-bit entry point, but fail to decode it, fall
675 * back to the legacy one (if available)
676 */
677 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) {
678 p = dmi_early_remap(phys_addr: efi.smbios3, size: 32);
679 if (p == NULL)
680 goto error;
681 memcpy_fromio(buf, p, 32);
682 dmi_early_unmap(addr: p, size: 32);
683
684 if (!dmi_smbios3_present(buf)) {
685 dmi_available = 1;
686 return;
687 }
688 }
689 if (efi.smbios == EFI_INVALID_TABLE_ADDR)
690 goto error;
691
692 /* This is called as a core_initcall() because it isn't
693 * needed during early boot. This also means we can
694 * iounmap the space when we're done with it.
695 */
696 p = dmi_early_remap(phys_addr: efi.smbios, size: 32);
697 if (p == NULL)
698 goto error;
699 memcpy_fromio(buf, p, 32);
700 dmi_early_unmap(addr: p, size: 32);
701
702 if (!dmi_present(buf)) {
703 dmi_available = 1;
704 return;
705 }
706 } else if (IS_ENABLED(CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK)) {
707 p = dmi_early_remap(SMBIOS_ENTRY_POINT_SCAN_START, size: 0x10000);
708 if (p == NULL)
709 goto error;
710
711 /*
712 * Same logic as above, look for a 64-bit entry point
713 * first, and if not found, fall back to 32-bit entry point.
714 */
715 memcpy_fromio(buf, p, 16);
716 for (q = p + 16; q < p + 0x10000; q += 16) {
717 memcpy_fromio(buf + 16, q, 16);
718 if (!dmi_smbios3_present(buf)) {
719 dmi_available = 1;
720 dmi_early_unmap(addr: p, size: 0x10000);
721 return;
722 }
723 memcpy(buf, buf + 16, 16);
724 }
725
726 /*
727 * Iterate over all possible DMI header addresses q.
728 * Maintain the 32 bytes around q in buf. On the
729 * first iteration, substitute zero for the
730 * out-of-range bytes so there is no chance of falsely
731 * detecting an SMBIOS header.
732 */
733 memset(buf, 0, 16);
734 for (q = p; q < p + 0x10000; q += 16) {
735 memcpy_fromio(buf + 16, q, 16);
736 if (!dmi_present(buf)) {
737 dmi_available = 1;
738 dmi_early_unmap(addr: p, size: 0x10000);
739 return;
740 }
741 memcpy(buf, buf + 16, 16);
742 }
743 dmi_early_unmap(addr: p, size: 0x10000);
744 }
745 error:
746 pr_info("DMI not present or invalid.\n");
747}
748
749static ssize_t raw_table_read(struct file *file, struct kobject *kobj,
750 struct bin_attribute *attr, char *buf,
751 loff_t pos, size_t count)
752{
753 memcpy(buf, attr->private + pos, count);
754 return count;
755}
756
757static BIN_ATTR(smbios_entry_point, S_IRUSR, raw_table_read, NULL, 0);
758static BIN_ATTR(DMI, S_IRUSR, raw_table_read, NULL, 0);
759
760static int __init dmi_init(void)
761{
762 struct kobject *tables_kobj;
763 u8 *dmi_table;
764 int ret = -ENOMEM;
765
766 if (!dmi_available)
767 return 0;
768
769 /*
770 * Set up dmi directory at /sys/firmware/dmi. This entry should stay
771 * even after farther error, as it can be used by other modules like
772 * dmi-sysfs.
773 */
774 dmi_kobj = kobject_create_and_add(name: "dmi", parent: firmware_kobj);
775 if (!dmi_kobj)
776 goto err;
777
778 tables_kobj = kobject_create_and_add(name: "tables", parent: dmi_kobj);
779 if (!tables_kobj)
780 goto err;
781
782 dmi_table = dmi_remap(dmi_base, dmi_len);
783 if (!dmi_table)
784 goto err_tables;
785
786 bin_attr_smbios_entry_point.size = smbios_entry_point_size;
787 bin_attr_smbios_entry_point.private = smbios_entry_point;
788 ret = sysfs_create_bin_file(kobj: tables_kobj, attr: &bin_attr_smbios_entry_point);
789 if (ret)
790 goto err_unmap;
791
792 bin_attr_DMI.size = dmi_len;
793 bin_attr_DMI.private = dmi_table;
794 ret = sysfs_create_bin_file(kobj: tables_kobj, attr: &bin_attr_DMI);
795 if (!ret)
796 return 0;
797
798 sysfs_remove_bin_file(kobj: tables_kobj,
799 attr: &bin_attr_smbios_entry_point);
800 err_unmap:
801 dmi_unmap(dmi_table);
802 err_tables:
803 kobject_del(kobj: tables_kobj);
804 kobject_put(kobj: tables_kobj);
805 err:
806 pr_err("dmi: Firmware registration failed.\n");
807
808 return ret;
809}
810subsys_initcall(dmi_init);
811
812/**
813 * dmi_setup - scan and setup DMI system information
814 *
815 * Scan the DMI system information. This setups DMI identifiers
816 * (dmi_system_id) for printing it out on task dumps and prepares
817 * DIMM entry information (dmi_memdev_info) from the SMBIOS table
818 * for using this when reporting memory errors.
819 */
820void __init dmi_setup(void)
821{
822 dmi_scan_machine();
823 if (!dmi_available)
824 return;
825
826 dmi_memdev_walk();
827 dump_stack_set_arch_desc(fmt: "%s", dmi_ids_string);
828}
829
830/**
831 * dmi_matches - check if dmi_system_id structure matches system DMI data
832 * @dmi: pointer to the dmi_system_id structure to check
833 */
834static bool dmi_matches(const struct dmi_system_id *dmi)
835{
836 int i;
837
838 for (i = 0; i < ARRAY_SIZE(dmi->matches); i++) {
839 int s = dmi->matches[i].slot;
840 if (s == DMI_NONE)
841 break;
842 if (s == DMI_OEM_STRING) {
843 /* DMI_OEM_STRING must be exact match */
844 const struct dmi_device *valid;
845
846 valid = dmi_find_device(type: DMI_DEV_TYPE_OEM_STRING,
847 name: dmi->matches[i].substr, NULL);
848 if (valid)
849 continue;
850 } else if (dmi_ident[s]) {
851 if (dmi->matches[i].exact_match) {
852 if (!strcmp(dmi_ident[s],
853 dmi->matches[i].substr))
854 continue;
855 } else {
856 if (strstr(dmi_ident[s],
857 dmi->matches[i].substr))
858 continue;
859 }
860 }
861
862 /* No match */
863 return false;
864 }
865 return true;
866}
867
868/**
869 * dmi_is_end_of_table - check for end-of-table marker
870 * @dmi: pointer to the dmi_system_id structure to check
871 */
872static bool dmi_is_end_of_table(const struct dmi_system_id *dmi)
873{
874 return dmi->matches[0].slot == DMI_NONE;
875}
876
877/**
878 * dmi_check_system - check system DMI data
879 * @list: array of dmi_system_id structures to match against
880 * All non-null elements of the list must match
881 * their slot's (field index's) data (i.e., each
882 * list string must be a substring of the specified
883 * DMI slot's string data) to be considered a
884 * successful match.
885 *
886 * Walk the blacklist table running matching functions until someone
887 * returns non zero or we hit the end. Callback function is called for
888 * each successful match. Returns the number of matches.
889 *
890 * dmi_setup must be called before this function is called.
891 */
892int dmi_check_system(const struct dmi_system_id *list)
893{
894 int count = 0;
895 const struct dmi_system_id *d;
896
897 for (d = list; !dmi_is_end_of_table(dmi: d); d++)
898 if (dmi_matches(dmi: d)) {
899 count++;
900 if (d->callback && d->callback(d))
901 break;
902 }
903
904 return count;
905}
906EXPORT_SYMBOL(dmi_check_system);
907
908/**
909 * dmi_first_match - find dmi_system_id structure matching system DMI data
910 * @list: array of dmi_system_id structures to match against
911 * All non-null elements of the list must match
912 * their slot's (field index's) data (i.e., each
913 * list string must be a substring of the specified
914 * DMI slot's string data) to be considered a
915 * successful match.
916 *
917 * Walk the blacklist table until the first match is found. Return the
918 * pointer to the matching entry or NULL if there's no match.
919 *
920 * dmi_setup must be called before this function is called.
921 */
922const struct dmi_system_id *dmi_first_match(const struct dmi_system_id *list)
923{
924 const struct dmi_system_id *d;
925
926 for (d = list; !dmi_is_end_of_table(dmi: d); d++)
927 if (dmi_matches(dmi: d))
928 return d;
929
930 return NULL;
931}
932EXPORT_SYMBOL(dmi_first_match);
933
934/**
935 * dmi_get_system_info - return DMI data value
936 * @field: data index (see enum dmi_field)
937 *
938 * Returns one DMI data value, can be used to perform
939 * complex DMI data checks.
940 */
941const char *dmi_get_system_info(int field)
942{
943 return dmi_ident[field];
944}
945EXPORT_SYMBOL(dmi_get_system_info);
946
947/**
948 * dmi_name_in_serial - Check if string is in the DMI product serial information
949 * @str: string to check for
950 */
951int dmi_name_in_serial(const char *str)
952{
953 int f = DMI_PRODUCT_SERIAL;
954 if (dmi_ident[f] && strstr(dmi_ident[f], str))
955 return 1;
956 return 0;
957}
958
959/**
960 * dmi_name_in_vendors - Check if string is in the DMI system or board vendor name
961 * @str: Case sensitive Name
962 */
963int dmi_name_in_vendors(const char *str)
964{
965 static int fields[] = { DMI_SYS_VENDOR, DMI_BOARD_VENDOR, DMI_NONE };
966 int i;
967 for (i = 0; fields[i] != DMI_NONE; i++) {
968 int f = fields[i];
969 if (dmi_ident[f] && strstr(dmi_ident[f], str))
970 return 1;
971 }
972 return 0;
973}
974EXPORT_SYMBOL(dmi_name_in_vendors);
975
976/**
977 * dmi_find_device - find onboard device by type/name
978 * @type: device type or %DMI_DEV_TYPE_ANY to match all device types
979 * @name: device name string or %NULL to match all
980 * @from: previous device found in search, or %NULL for new search.
981 *
982 * Iterates through the list of known onboard devices. If a device is
983 * found with a matching @type and @name, a pointer to its device
984 * structure is returned. Otherwise, %NULL is returned.
985 * A new search is initiated by passing %NULL as the @from argument.
986 * If @from is not %NULL, searches continue from next device.
987 */
988const struct dmi_device *dmi_find_device(int type, const char *name,
989 const struct dmi_device *from)
990{
991 const struct list_head *head = from ? &from->list : &dmi_devices;
992 struct list_head *d;
993
994 for (d = head->next; d != &dmi_devices; d = d->next) {
995 const struct dmi_device *dev =
996 list_entry(d, struct dmi_device, list);
997
998 if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
999 ((name == NULL) || (strcmp(dev->name, name) == 0)))
1000 return dev;
1001 }
1002
1003 return NULL;
1004}
1005EXPORT_SYMBOL(dmi_find_device);
1006
1007/**
1008 * dmi_get_date - parse a DMI date
1009 * @field: data index (see enum dmi_field)
1010 * @yearp: optional out parameter for the year
1011 * @monthp: optional out parameter for the month
1012 * @dayp: optional out parameter for the day
1013 *
1014 * The date field is assumed to be in the form resembling
1015 * [mm[/dd]]/yy[yy] and the result is stored in the out
1016 * parameters any or all of which can be omitted.
1017 *
1018 * If the field doesn't exist, all out parameters are set to zero
1019 * and false is returned. Otherwise, true is returned with any
1020 * invalid part of date set to zero.
1021 *
1022 * On return, year, month and day are guaranteed to be in the
1023 * range of [0,9999], [0,12] and [0,31] respectively.
1024 */
1025bool dmi_get_date(int field, int *yearp, int *monthp, int *dayp)
1026{
1027 int year = 0, month = 0, day = 0;
1028 bool exists;
1029 const char *s, *y;
1030 char *e;
1031
1032 s = dmi_get_system_info(field);
1033 exists = s;
1034 if (!exists)
1035 goto out;
1036
1037 /*
1038 * Determine year first. We assume the date string resembles
1039 * mm/dd/yy[yy] but the original code extracted only the year
1040 * from the end. Keep the behavior in the spirit of no
1041 * surprises.
1042 */
1043 y = strrchr(s, '/');
1044 if (!y)
1045 goto out;
1046
1047 y++;
1048 year = simple_strtoul(y, &e, 10);
1049 if (y != e && year < 100) { /* 2-digit year */
1050 year += 1900;
1051 if (year < 1996) /* no dates < spec 1.0 */
1052 year += 100;
1053 }
1054 if (year > 9999) /* year should fit in %04d */
1055 year = 0;
1056
1057 /* parse the mm and dd */
1058 month = simple_strtoul(s, &e, 10);
1059 if (s == e || *e != '/' || !month || month > 12) {
1060 month = 0;
1061 goto out;
1062 }
1063
1064 s = e + 1;
1065 day = simple_strtoul(s, &e, 10);
1066 if (s == y || s == e || *e != '/' || day > 31)
1067 day = 0;
1068out:
1069 if (yearp)
1070 *yearp = year;
1071 if (monthp)
1072 *monthp = month;
1073 if (dayp)
1074 *dayp = day;
1075 return exists;
1076}
1077EXPORT_SYMBOL(dmi_get_date);
1078
1079/**
1080 * dmi_get_bios_year - get a year out of DMI_BIOS_DATE field
1081 *
1082 * Returns year on success, -ENXIO if DMI is not selected,
1083 * or a different negative error code if DMI field is not present
1084 * or not parseable.
1085 */
1086int dmi_get_bios_year(void)
1087{
1088 bool exists;
1089 int year;
1090
1091 exists = dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL);
1092 if (!exists)
1093 return -ENODATA;
1094
1095 return year ? year : -ERANGE;
1096}
1097EXPORT_SYMBOL(dmi_get_bios_year);
1098
1099/**
1100 * dmi_walk - Walk the DMI table and get called back for every record
1101 * @decode: Callback function
1102 * @private_data: Private data to be passed to the callback function
1103 *
1104 * Returns 0 on success, -ENXIO if DMI is not selected or not present,
1105 * or a different negative error code if DMI walking fails.
1106 */
1107int dmi_walk(void (*decode)(const struct dmi_header *, void *),
1108 void *private_data)
1109{
1110 u8 *buf;
1111
1112 if (!dmi_available)
1113 return -ENXIO;
1114
1115 buf = dmi_remap(dmi_base, dmi_len);
1116 if (buf == NULL)
1117 return -ENOMEM;
1118
1119 dmi_decode_table(buf, decode, private_data);
1120
1121 dmi_unmap(buf);
1122 return 0;
1123}
1124EXPORT_SYMBOL_GPL(dmi_walk);
1125
1126/**
1127 * dmi_match - compare a string to the dmi field (if exists)
1128 * @f: DMI field identifier
1129 * @str: string to compare the DMI field to
1130 *
1131 * Returns true if the requested field equals to the str (including NULL).
1132 */
1133bool dmi_match(enum dmi_field f, const char *str)
1134{
1135 const char *info = dmi_get_system_info(f);
1136
1137 if (info == NULL || str == NULL)
1138 return info == str;
1139
1140 return !strcmp(info, str);
1141}
1142EXPORT_SYMBOL_GPL(dmi_match);
1143
1144void dmi_memdev_name(u16 handle, const char **bank, const char **device)
1145{
1146 int n;
1147
1148 if (dmi_memdev == NULL)
1149 return;
1150
1151 for (n = 0; n < dmi_memdev_nr; n++) {
1152 if (handle == dmi_memdev[n].handle) {
1153 *bank = dmi_memdev[n].bank;
1154 *device = dmi_memdev[n].device;
1155 break;
1156 }
1157 }
1158}
1159EXPORT_SYMBOL_GPL(dmi_memdev_name);
1160
1161u64 dmi_memdev_size(u16 handle)
1162{
1163 int n;
1164
1165 if (dmi_memdev) {
1166 for (n = 0; n < dmi_memdev_nr; n++) {
1167 if (handle == dmi_memdev[n].handle)
1168 return dmi_memdev[n].size;
1169 }
1170 }
1171 return ~0ull;
1172}
1173EXPORT_SYMBOL_GPL(dmi_memdev_size);
1174
1175/**
1176 * dmi_memdev_type - get the memory type
1177 * @handle: DMI structure handle
1178 *
1179 * Return the DMI memory type of the module in the slot associated with the
1180 * given DMI handle, or 0x0 if no such DMI handle exists.
1181 */
1182u8 dmi_memdev_type(u16 handle)
1183{
1184 int n;
1185
1186 if (dmi_memdev) {
1187 for (n = 0; n < dmi_memdev_nr; n++) {
1188 if (handle == dmi_memdev[n].handle)
1189 return dmi_memdev[n].type;
1190 }
1191 }
1192 return 0x0; /* Not a valid value */
1193}
1194EXPORT_SYMBOL_GPL(dmi_memdev_type);
1195
1196/**
1197 * dmi_memdev_handle - get the DMI handle of a memory slot
1198 * @slot: slot number
1199 *
1200 * Return the DMI handle associated with a given memory slot, or %0xFFFF
1201 * if there is no such slot.
1202 */
1203u16 dmi_memdev_handle(int slot)
1204{
1205 if (dmi_memdev && slot >= 0 && slot < dmi_memdev_nr)
1206 return dmi_memdev[slot].handle;
1207
1208 return 0xffff; /* Not a valid value */
1209}
1210EXPORT_SYMBOL_GPL(dmi_memdev_handle);
1211

source code of linux/drivers/firmware/dmi_scan.c