aboutsummaryrefslogtreecommitdiff
path: root/drivers/firmware/dmi_scan.c
blob: 8daf4793ac32485824194af5e14f332c50fc6f26 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
#include <linux/types.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/dmi.h>
#include <linux/efi.h>
#include <linux/bootmem.h>
#include <linux/slab.h>
#include <asm/dmi.h>

/*
 * DMI stands for "Desktop Management Interface".  It is part
 * of and an antecedent to, SMBIOS, which stands for System
 * Management BIOS.  See further: http://www.dmtf.org/standards
 */
static char dmi_empty_string[] = "        ";

/*
 * Catch too early calls to dmi_check_system():
 */
static int dmi_initialized;

static const char * __init dmi_string_nosave(const struct dmi_header *dm, u8 s)
{
	const u8 *bp = ((u8 *) dm) + dm->length;

	if (s) {
		s--;
		while (s > 0 && *bp) {
			bp += strlen(bp) + 1;
			s--;
		}

		if (*bp != 0) {
			size_t len = strlen(bp)+1;
			size_t cmp_len = len > 8 ? 8 : len;

			if (!memcmp(bp, dmi_empty_string, cmp_len))
				return dmi_empty_string;
			return bp;
		}
	}

	return "";
}

static char * __init dmi_string(const struct dmi_header *dm, u8 s)
{
	const char *bp = dmi_string_nosave(dm, s);
	char *str;
	size_t len;

	if (bp == dmi_empty_string)
		return dmi_empty_string;

	len = strlen(bp) + 1;
	str = dmi_alloc(len);
	if (str != NULL)
		strcpy(str, bp);
	else
		printk(KERN_ERR "dmi_string: cannot allocate %Zu bytes.\n", len);

	return str;
}

/*
 *	We have to be cautious here. We have seen BIOSes with DMI pointers
 *	pointing to completely the wrong place for example
 */
static void dmi_table(u8 *buf, int len, int num,
		      void (*decode)(const struct dmi_header *))
{
	u8 *data = buf;
	int i = 0;

	/*
	 *	Stop when we see all the items the table claimed to have
	 *	OR we run off the end of the table (also happens)
	 */
	while ((i < num) && (data - buf + sizeof(struct dmi_header)) <= len) {
		const struct dmi_header *dm = (const struct dmi_header *)data;

		/*
		 *  We want to know the total length (formatted area and
		 *  strings) before decoding to make sure we won't run off the
		 *  table in dmi_decode or dmi_string
		 */
		data += dm->length;
		while ((data - buf < len - 1) && (data[0] || data[1]))
			data++;
		if (data - buf < len - 1)
			decode(dm);
		data += 2;
		i++;
	}
}

static u32 dmi_base;
static u16 dmi_len;
static u16 dmi_num;

static int __init dmi_walk_early(void (*decode)(const struct dmi_header *))
{
	u8 *buf;

	buf = dmi_ioremap(dmi_base, dmi_len);
	if (buf == NULL)
		return -1;

	dmi_table(buf, dmi_len, dmi_num, decode);

	dmi_iounmap(buf, dmi_len);
	return 0;
}

static int __init dmi_checksum(const u8 *buf)
{
	u8 sum = 0;
	int a;

	for (a = 0; a < 15; a++)
		sum += buf[a];

	return sum == 0;
}

static char *dmi_ident[DMI_STRING_MAX];
static LIST_HEAD(dmi_devices);
int dmi_available;

/*
 *	Save a DMI string
 */
static void __init dmi_save_ident(const struct dmi_header *dm, int slot, int string)
{
	const char *d = (const char*) dm;
	char *p;

	if (dmi_ident[slot])
		return;

	p = dmi_string(dm, d[string]);
	if (p == NULL)
		return;

	dmi_ident[slot] = p;
}

static void __init dmi_save_uuid(const struct dmi_header *dm, int slot, int index)
{
	const u8 *d = (u8*) dm + index;
	char *s;
	int is_ff = 1, is_00 = 1, i;

	if (dmi_ident[slot])
		return;

	for (i = 0; i < 16 && (is_ff || is_00); i++) {
		if(d[i] != 0x00) is_ff = 0;
		if(d[i] != 0xFF) is_00 = 0;
	}

	if (is_ff || is_00)
		return;

	s = dmi_alloc(16*2+4+1);
	if (!s)
		return;

	sprintf(s,
		"%02X%02X%02X%02X-%02X%02X-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X",
		d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7],
		d[8], d[9], d[10], d[11], d[12], d[13], d[14], d[15]);

        dmi_ident[slot] = s;
}

static void __init dmi_save_type(const struct dmi_header *dm, int slot, int index)
{
	const u8 *d = (u8*) dm + index;
	char *s;

	if (dmi_ident[slot])
		return;

	s = dmi_alloc(4);
	if (!s)
		return;

	sprintf(s, "%u", *d & 0x7F);
	dmi_ident[slot] = s;
}

static void __init dmi_save_one_device(int type, const char *name)
{
	struct dmi_device *dev;

	/* No duplicate device */
	if (dmi_find_device(type, name, NULL))
		return;

	dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
	if (!dev) {
		printk(KERN_ERR "dmi_save_one_device: out of memory.\n");
		return;
	}

	dev->type = type;
	strcpy((char *)(dev + 1), name);
	dev->name = (char *)(dev + 1);
	dev->device_data = NULL;
	list_add(&dev->list, &dmi_devices);
}

static void __init dmi_save_devices(const struct dmi_header *dm)
{
	int i, count = (dm->length - sizeof(struct dmi_header)) / 2;

	for (i = 0; i < count; i++) {
		const char *d = (char *)(dm + 1) + (i * 2);

		/* Skip disabled device */
		if ((*d & 0x80) == 0)
			continue;

		dmi_save_one_device(*d & 0x7f, dmi_string_nosave(dm, *(d + 1)));
	}
}

static void __init dmi_save_oem_strings_devices(const struct dmi_header *dm)
{
	int i, count = *(u8 *)(dm + 1);
	struct dmi_device *dev;

	for (i = 1; i <= count; i++) {
		char *devname = dmi_string(dm, i);

		if (devname == dmi_empty_string)
			continue;

		dev = dmi_alloc(sizeof(*dev));
		if (!dev) {
			printk(KERN_ERR
			   "dmi_save_oem_strings_devices: out of memory.\n");
			break;
		}

		dev->type = DMI_DEV_TYPE_OEM_STRING;
		dev->name = devname;
		dev->device_data = NULL;

		list_add(&dev->list, &dmi_devices);
	}
}

static void __init dmi_save_ipmi_device(const struct dmi_header *dm)
{
	struct dmi_device *dev;
	void * data;

	data = dmi_alloc(dm->length);
	if (data == NULL) {
		printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
		return;
	}

	memcpy(data, dm, dm->length);

	dev = dmi_alloc(sizeof(*dev));
	if (!dev) {
		printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
		return;
	}

	dev->type = DMI_DEV_TYPE_IPMI;
	dev->name = "IPMI controller";
	dev->device_data = data;

	list_add_tail(&dev->list, &dmi_devices);
}

static void __init dmi_save_extended_devices(const struct dmi_header *dm)
{
	const u8 *d = (u8*) dm + 5;

	/* Skip disabled device */
	if ((*d & 0x80) == 0)
		return;

	dmi_save_one_device(*d & 0x7f, dmi_string_nosave(dm, *(d - 1)));
}

/*
 *	Process a DMI table entry. Right now all we care about are the BIOS
 *	and machine entries. For 2.5 we should pull the smbus controller info
 *	out of here.
 */
static void __init dmi_decode(const struct dmi_header *dm)
{
	switch(dm->type) {
	case 0:		/* BIOS Information */
		dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
		dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
		dmi_save_ident(dm, DMI_BIOS_DATE, 8);
		break;
	case 1:		/* System Information */
		dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
		dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
		dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
		dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
		dmi_save_uuid(dm, DMI_PRODUCT_UUID, 8);
		break;
	case 2:		/* Base Board Information */
		dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
		dmi_save_ident(dm, DMI_BOARD_NAME, 5);
		dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
		dmi_save_ident(dm, DMI_BOARD_SERIAL, 7);
		dmi_save_ident(dm, DMI_BOARD_ASSET_TAG, 8);
		break;
	case 3:		/* Chassis Information */
		dmi_save_ident(dm, DMI_CHASSIS_VENDOR, 4);
		dmi_save_type(dm, DMI_CHASSIS_TYPE, 5);
		dmi_save_ident(dm, DMI_CHASSIS_VERSION, 6);
		dmi_save_ident(dm, DMI_CHASSIS_SERIAL, 7);
		dmi_save_ident(dm, DMI_CHASSIS_ASSET_TAG, 8);
		break;
	case 10:	/* Onboard Devices Information */
		dmi_save_devices(dm);
		break;
	case 11:	/* OEM Strings */
		dmi_save_oem_strings_devices(dm);
		break;
	case 38:	/* IPMI Device Information */
		dmi_save_ipmi_device(dm);
		break;
	case 41:	/* Onboard Devices Extended Information */
		dmi_save_extended_devices(dm);
	}
}

static int __init dmi_present(const char __iomem *p)
{
	u8 buf[15];

	memcpy_fromio(buf, p, 15);
	if ((memcmp(buf, "_DMI_", 5) == 0) && dmi_checksum(buf)) {
		dmi_num = (buf[13] << 8) | buf[12];
		dmi_len = (buf[7] << 8) | buf[6];
		dmi_base = (buf[11] << 24) | (buf[10] << 16) |
			(buf[9] << 8) | buf[8];

		/*
		 * DMI version 0.0 means that the real version is taken from
		 * the SMBIOS version, which we don't know at this point.
		 */
		if (buf[14] != 0)
			printk(KERN_INFO "DMI %d.%d present.\n",
			       buf[14] >> 4, buf[14] & 0xF);
		else
			printk(KERN_INFO "DMI present.\n");
		if (dmi_walk_early(dmi_decode) == 0)
			return 0;
	}
	return 1;
}

void __init dmi_scan_machine(void)
{
	char __iomem *p, *q;
	int rc;

	if (efi_enabled) {
		if (efi.smbios == EFI_INVALID_TABLE_ADDR)
			goto error;

		/* This is called as a core_initcall() because it isn't
		 * needed during early boot.  This also means we can
		 * iounmap the space when we're done with it.
		 */
		p = dmi_ioremap(efi.smbios, 32);
		if (p == NULL)
			goto error;

		rc = dmi_present(p + 0x10); /* offset of _DMI_ string */
		dmi_iounmap(p, 32);
		if (!rc) {
			dmi_available = 1;
			goto out;
		}
	}
	else {
		/*
		 * no iounmap() for that ioremap(); it would be a no-op, but
		 * it's so early in setup that sucker gets confused into doing
		 * what it shouldn't if we actually call it.
		 */
		p = dmi_ioremap(0xF0000, 0x10000);
		if (p == NULL)
			goto error;

		for (q = p; q < p + 0x10000; q += 16) {
			rc = dmi_present(q);
			if (!rc) {
				dmi_available = 1;
				dmi_iounmap(p, 0x10000);
				goto out;
			}
		}
		dmi_iounmap(p, 0x10000);
	}
 error:
	printk(KERN_INFO "DMI not present or invalid.\n");
 out:
	dmi_initialized = 1;
}

/**
 *	dmi_check_system - check system DMI data
 *	@list: array of dmi_system_id structures to match against
 *		All non-null elements of the list must match
 *		their slot's (field index's) data (i.e., each
 *		list string must be a substring of the specified
 *		DMI slot's string data) to be considered a
 *		successful match.
 *
 *	Walk the blacklist table running matching functions until someone
 *	returns non zero or we hit the end. Callback function is called for
 *	each successful match. Returns the number of matches.
 */
int dmi_check_system(const struct dmi_system_id *list)
{
	int i, count = 0;
	const struct dmi_system_id *d = list;

	WARN(!dmi_initialized, KERN_ERR "dmi check: not initialized yet.\n");

	while (d->ident) {
		for (i = 0; i < ARRAY_SIZE(d->matches); i++) {
			int s = d->matches[i].slot;
			if (s == DMI_NONE)
				continue;
			if (dmi_ident[s] && strstr(dmi_ident[s], d->matches[i].substr))
				continue;
			/* No match */
			goto fail;
		}
		count++;
		if (d->callback && d->callback(d))
			break;
fail:		d++;
	}

	return count;
}
EXPORT_SYMBOL(dmi_check_system);

/**
 *	dmi_get_system_info - return DMI data value
 *	@field: data index (see enum dmi_field)
 *
 *	Returns one DMI data value, can be used to perform
 *	complex DMI data checks.
 */
const char *dmi_get_system_info(int field)
{
	return dmi_ident[field];
}
EXPORT_SYMBOL(dmi_get_system_info);


/**
 *	dmi_name_in_vendors - Check if string is anywhere in the DMI vendor information.
 *	@str: 	Case sensitive Name
 */
int dmi_name_in_vendors(const char *str)
{
	static int fields[] = { DMI_BIOS_VENDOR, DMI_BIOS_VERSION, DMI_SYS_VENDOR,
				DMI_PRODUCT_NAME, DMI_PRODUCT_VERSION, DMI_BOARD_VENDOR,
				DMI_BOARD_NAME, DMI_BOARD_VERSION, DMI_NONE };
	int i;
	for (i = 0; fields[i] != DMI_NONE; i++) {
		int f = fields[i];
		if (dmi_ident[f] && strstr(dmi_ident[f], str))
			return 1;
	}
	return 0;
}
EXPORT_SYMBOL(dmi_name_in_vendors);

/**
 *	dmi_find_device - find onboard device by type/name
 *	@type: device type or %DMI_DEV_TYPE_ANY to match all device types
 *	@name: device name string or %NULL to match all
 *	@from: previous device found in search, or %NULL for new search.
 *
 *	Iterates through the list of known onboard devices. If a device is
 *	found with a matching @vendor and @device, a pointer to its device
 *	structure is returned.  Otherwise, %NULL is returned.
 *	A new search is initiated by passing %NULL as the @from argument.
 *	If @from is not %NULL, searches continue from next device.
 */
const struct dmi_device * dmi_find_device(int type, const char *name,
				    const struct dmi_device *from)
{
	const struct list_head *head = from ? &from->list : &dmi_devices;
	struct list_head *d;

	for(d = head->next; d != &dmi_devices; d = d->next) {
		const struct dmi_device *dev =
			list_entry(d, struct dmi_device, list);

		if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
		    ((name == NULL) || (strcmp(dev->name, name) == 0)))
			return dev;
	}

	return NULL;
}
EXPORT_SYMBOL(dmi_find_device);

/**
 *	dmi_get_year - Return year of a DMI date
 *	@field:	data index (like dmi_get_system_info)
 *
 *	Returns -1 when the field doesn't exist. 0 when it is broken.
 */
int dmi_get_year(int field)
{
	int year;
	const char *s = dmi_get_system_info(field);

	if (!s)
		return -1;
	if (*s == '\0')
		return 0;
	s = strrchr(s, '/');
	if (!s)
		return 0;

	s += 1;
	year = simple_strtoul(s, NULL, 0);
	if (year && year < 100) {	/* 2-digit year */
		year += 1900;
		if (year < 1996)	/* no dates < spec 1.0 */
			year += 100;
	}

	return year;
}

/**
 *	dmi_walk - Walk the DMI table and get called back for every record
 *	@decode: Callback function
 *
 *	Returns -1 when the DMI table can't be reached, 0 on success.
 */
int dmi_walk(void (*decode)(const struct dmi_header *))
{
	u8 *buf;

	if (!dmi_available)
		return -1;

	buf = ioremap(dmi_base, dmi_len);
	if (buf == NULL)
		return -1;

	dmi_table(buf, dmi_len, dmi_num, decode);

	iounmap(buf);
	return 0;
}
EXPORT_SYMBOL_GPL(dmi_walk);