1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/types.h>
3 #include <linux/string.h>
4 #include <linux/init.h>
5 #include <linux/module.h>
6 #include <linux/ctype.h>
7 #include <linux/dmi.h>
8 #include <linux/efi.h>
9 #include <linux/memblock.h>
10 #include <linux/random.h>
11 #include <asm/dmi.h>
12 #include <asm/unaligned.h>
13
14 #ifndef SMBIOS_ENTRY_POINT_SCAN_START
15 #define SMBIOS_ENTRY_POINT_SCAN_START 0xF0000
16 #endif
17
18 struct kobject *dmi_kobj;
19 EXPORT_SYMBOL_GPL(dmi_kobj);
20
21 /*
22 * DMI stands for "Desktop Management Interface". It is part
23 * of and an antecedent to, SMBIOS, which stands for System
24 * Management BIOS. See further: https://www.dmtf.org/standards
25 */
26 static const char dmi_empty_string[] = "";
27
28 static u32 dmi_ver __initdata;
29 static u32 dmi_len;
30 static u16 dmi_num;
31 static u8 smbios_entry_point[32];
32 static int smbios_entry_point_size;
33
34 /* DMI system identification string used during boot */
35 static char dmi_ids_string[128] __initdata;
36
37 static struct dmi_memdev_info {
38 const char *device;
39 const char *bank;
40 u64 size; /* bytes */
41 u16 handle;
42 u8 type; /* DDR2, DDR3, DDR4 etc */
43 } *dmi_memdev;
44 static int dmi_memdev_nr;
45
dmi_string_nosave(const struct dmi_header * dm,u8 s)46 static const char * __init dmi_string_nosave(const struct dmi_header *dm, u8 s)
47 {
48 const u8 *bp = ((u8 *) dm) + dm->length;
49 const u8 *nsp;
50
51 if (s) {
52 while (--s > 0 && *bp)
53 bp += strlen(bp) + 1;
54
55 /* Strings containing only spaces are considered empty */
56 nsp = bp;
57 while (*nsp == ' ')
58 nsp++;
59 if (*nsp != '\0')
60 return bp;
61 }
62
63 return dmi_empty_string;
64 }
65
dmi_string(const struct dmi_header * dm,u8 s)66 static const char * __init dmi_string(const struct dmi_header *dm, u8 s)
67 {
68 const char *bp = dmi_string_nosave(dm, s);
69 char *str;
70 size_t len;
71
72 if (bp == dmi_empty_string)
73 return dmi_empty_string;
74
75 len = strlen(bp) + 1;
76 str = dmi_alloc(len);
77 if (str != NULL)
78 strcpy(str, bp);
79
80 return str;
81 }
82
83 /*
84 * We have to be cautious here. We have seen BIOSes with DMI pointers
85 * pointing to completely the wrong place for example
86 */
dmi_decode_table(u8 * buf,void (* decode)(const struct dmi_header *,void *),void * private_data)87 static void dmi_decode_table(u8 *buf,
88 void (*decode)(const struct dmi_header *, void *),
89 void *private_data)
90 {
91 u8 *data = buf;
92 int i = 0;
93
94 /*
95 * Stop when we have seen all the items the table claimed to have
96 * (SMBIOS < 3.0 only) OR we reach an end-of-table marker (SMBIOS
97 * >= 3.0 only) OR we run off the end of the table (should never
98 * happen but sometimes does on bogus implementations.)
99 */
100 while ((!dmi_num || i < dmi_num) &&
101 (data - buf + sizeof(struct dmi_header)) <= dmi_len) {
102 const struct dmi_header *dm = (const struct dmi_header *)data;
103
104 /*
105 * We want to know the total length (formatted area and
106 * strings) before decoding to make sure we won't run off the
107 * table in dmi_decode or dmi_string
108 */
109 data += dm->length;
110 while ((data - buf < dmi_len - 1) && (data[0] || data[1]))
111 data++;
112 if (data - buf < dmi_len - 1)
113 decode(dm, private_data);
114
115 data += 2;
116 i++;
117
118 /*
119 * 7.45 End-of-Table (Type 127) [SMBIOS reference spec v3.0.0]
120 * For tables behind a 64-bit entry point, we have no item
121 * count and no exact table length, so stop on end-of-table
122 * marker. For tables behind a 32-bit entry point, we have
123 * seen OEM structures behind the end-of-table marker on
124 * some systems, so don't trust it.
125 */
126 if (!dmi_num && dm->type == DMI_ENTRY_END_OF_TABLE)
127 break;
128 }
129
130 /* Trim DMI table length if needed */
131 if (dmi_len > data - buf)
132 dmi_len = data - buf;
133 }
134
135 static phys_addr_t dmi_base;
136
dmi_walk_early(void (* decode)(const struct dmi_header *,void *))137 static int __init dmi_walk_early(void (*decode)(const struct dmi_header *,
138 void *))
139 {
140 u8 *buf;
141 u32 orig_dmi_len = dmi_len;
142
143 buf = dmi_early_remap(dmi_base, orig_dmi_len);
144 if (buf == NULL)
145 return -ENOMEM;
146
147 dmi_decode_table(buf, decode, NULL);
148
149 add_device_randomness(buf, dmi_len);
150
151 dmi_early_unmap(buf, orig_dmi_len);
152 return 0;
153 }
154
dmi_checksum(const u8 * buf,u8 len)155 static int __init dmi_checksum(const u8 *buf, u8 len)
156 {
157 u8 sum = 0;
158 int a;
159
160 for (a = 0; a < len; a++)
161 sum += buf[a];
162
163 return sum == 0;
164 }
165
166 static const char *dmi_ident[DMI_STRING_MAX];
167 static LIST_HEAD(dmi_devices);
168 int dmi_available;
169
170 /*
171 * Save a DMI string
172 */
dmi_save_ident(const struct dmi_header * dm,int slot,int string)173 static 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
dmi_save_release(const struct dmi_header * dm,int slot,int index)189 static 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
dmi_save_uuid(const struct dmi_header * dm,int slot,int index)217 static 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
dmi_save_type(const struct dmi_header * dm,int slot,int index)255 static 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
dmi_save_one_device(int type,const char * name)273 static 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
dmi_save_devices(const struct dmi_header * dm)292 static 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
dmi_save_oem_strings_devices(const struct dmi_header * dm)307 static 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
dmi_save_ipmi_device(const struct dmi_header * dm)334 static 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
dmi_save_dev_pciaddr(int instance,int segment,int bus,int devfn,const char * name,int type)356 static 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
dmi_save_extended_devices(const struct dmi_header * dm)383 static 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
dmi_save_system_slot(const struct dmi_header * dm)401 static 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
count_mem_devices(const struct dmi_header * dm,void * v)413 static 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
save_mem_devices(const struct dmi_header * dm,void * v)420 static 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
dmi_memdev_walk(void)454 static 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 */
dmi_decode(const struct dmi_header * dm,void * dummy)468 static 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
print_filtered(char * buf,size_t len,const char * info)518 static 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
dmi_format_ids(char * buf,size_t len)534 static 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 */
dmi_present(const u8 * buf)565 static 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 */
dmi_smbios3_present(const u8 * buf)628 static 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
dmi_scan_machine(void)651 static 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
raw_table_read(struct file * file,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t pos,size_t count)742 static 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
750 static BIN_ATTR(smbios_entry_point, S_IRUSR, raw_table_read, NULL, 0);
751 static BIN_ATTR(DMI, S_IRUSR, raw_table_read, NULL, 0);
752
dmi_init(void)753 static 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 }
803 subsys_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 */
dmi_setup(void)813 void __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 */
dmi_matches(const struct dmi_system_id * dmi)827 static 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 */
dmi_is_end_of_table(const struct dmi_system_id * dmi)865 static 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 */
dmi_check_system(const struct dmi_system_id * list)885 int 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 }
899 EXPORT_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 */
dmi_first_match(const struct dmi_system_id * list)915 const 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 }
925 EXPORT_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 */
dmi_get_system_info(int field)934 const char *dmi_get_system_info(int field)
935 {
936 return dmi_ident[field];
937 }
938 EXPORT_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 */
dmi_name_in_serial(const char * str)944 int 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 */
dmi_name_in_vendors(const char * str)956 int 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 }
967 EXPORT_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 */
dmi_find_device(int type,const char * name,const struct dmi_device * from)981 const 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 }
998 EXPORT_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 */
dmi_get_date(int field,int * yearp,int * monthp,int * dayp)1018 bool 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;
1061 out:
1062 if (yearp)
1063 *yearp = year;
1064 if (monthp)
1065 *monthp = month;
1066 if (dayp)
1067 *dayp = day;
1068 return exists;
1069 }
1070 EXPORT_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 */
dmi_get_bios_year(void)1079 int 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 }
1090 EXPORT_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 */
dmi_walk(void (* decode)(const struct dmi_header *,void *),void * private_data)1100 int 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 }
1117 EXPORT_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 */
dmi_match(enum dmi_field f,const char * str)1126 bool 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 }
1135 EXPORT_SYMBOL_GPL(dmi_match);
1136
dmi_memdev_name(u16 handle,const char ** bank,const char ** device)1137 void 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 }
1152 EXPORT_SYMBOL_GPL(dmi_memdev_name);
1153
dmi_memdev_size(u16 handle)1154 u64 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 }
1166 EXPORT_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 */
dmi_memdev_type(u16 handle)1175 u8 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 }
1187 EXPORT_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 */
dmi_memdev_handle(int slot)1196 u16 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 }
1203 EXPORT_SYMBOL_GPL(dmi_memdev_handle);
1204