xref: /openbmc/linux/drivers/firmware/dmi_scan.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
1 #include <linux/types.h>
2 #include <linux/string.h>
3 #include <linux/init.h>
4 #include <linux/module.h>
5 #include <linux/dmi.h>
6 #include <linux/efi.h>
7 #include <linux/bootmem.h>
8 #include <linux/slab.h>
9 #include <asm/dmi.h>
10 
11 static char * __init dmi_string(const struct dmi_header *dm, u8 s)
12 {
13 	const u8 *bp = ((u8 *) dm) + dm->length;
14 	char *str = "";
15 
16 	if (s) {
17 		s--;
18 		while (s > 0 && *bp) {
19 			bp += strlen(bp) + 1;
20 			s--;
21 		}
22 
23 		if (*bp != 0) {
24 			str = dmi_alloc(strlen(bp) + 1);
25 			if (str != NULL)
26 				strcpy(str, bp);
27 			else
28 				printk(KERN_ERR "dmi_string: out of memory.\n");
29 		}
30 	}
31 
32 	return str;
33 }
34 
35 /*
36  *	We have to be cautious here. We have seen BIOSes with DMI pointers
37  *	pointing to completely the wrong place for example
38  */
39 static int __init dmi_table(u32 base, int len, int num,
40 			    void (*decode)(const struct dmi_header *))
41 {
42 	u8 *buf, *data;
43 	int i = 0;
44 
45 	buf = dmi_ioremap(base, len);
46 	if (buf == NULL)
47 		return -1;
48 
49 	data = buf;
50 
51 	/*
52 	 *	Stop when we see all the items the table claimed to have
53 	 *	OR we run off the end of the table (also happens)
54 	 */
55 	while ((i < num) && (data - buf + sizeof(struct dmi_header)) <= len) {
56 		const struct dmi_header *dm = (const struct dmi_header *)data;
57 
58 		/*
59 		 *  We want to know the total length (formated area and strings)
60 		 *  before decoding to make sure we won't run off the table in
61 		 *  dmi_decode or dmi_string
62 		 */
63 		data += dm->length;
64 		while ((data - buf < len - 1) && (data[0] || data[1]))
65 			data++;
66 		if (data - buf < len - 1)
67 			decode(dm);
68 		data += 2;
69 		i++;
70 	}
71 	dmi_iounmap(buf, len);
72 	return 0;
73 }
74 
75 static int __init dmi_checksum(const u8 *buf)
76 {
77 	u8 sum = 0;
78 	int a;
79 
80 	for (a = 0; a < 15; a++)
81 		sum += buf[a];
82 
83 	return sum == 0;
84 }
85 
86 static char *dmi_ident[DMI_STRING_MAX];
87 static LIST_HEAD(dmi_devices);
88 int dmi_available;
89 
90 /*
91  *	Save a DMI string
92  */
93 static void __init dmi_save_ident(const struct dmi_header *dm, int slot, int string)
94 {
95 	const char *d = (const char*) dm;
96 	char *p;
97 
98 	if (dmi_ident[slot])
99 		return;
100 
101 	p = dmi_string(dm, d[string]);
102 	if (p == NULL)
103 		return;
104 
105 	dmi_ident[slot] = p;
106 }
107 
108 static void __init dmi_save_uuid(const struct dmi_header *dm, int slot, int index)
109 {
110 	const u8 *d = (u8*) dm + index;
111 	char *s;
112 	int is_ff = 1, is_00 = 1, i;
113 
114 	if (dmi_ident[slot])
115 		return;
116 
117 	for (i = 0; i < 16 && (is_ff || is_00); i++) {
118 		if(d[i] != 0x00) is_ff = 0;
119 		if(d[i] != 0xFF) is_00 = 0;
120 	}
121 
122 	if (is_ff || is_00)
123 		return;
124 
125 	s = dmi_alloc(16*2+4+1);
126 	if (!s)
127 		return;
128 
129 	sprintf(s,
130 		"%02X%02X%02X%02X-%02X%02X-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X",
131 		d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7],
132 		d[8], d[9], d[10], d[11], d[12], d[13], d[14], d[15]);
133 
134         dmi_ident[slot] = s;
135 }
136 
137 static void __init dmi_save_type(const struct dmi_header *dm, int slot, int index)
138 {
139 	const u8 *d = (u8*) dm + index;
140 	char *s;
141 
142 	if (dmi_ident[slot])
143 		return;
144 
145 	s = dmi_alloc(4);
146 	if (!s)
147 		return;
148 
149 	sprintf(s, "%u", *d & 0x7F);
150 	dmi_ident[slot] = s;
151 }
152 
153 static void __init dmi_save_devices(const struct dmi_header *dm)
154 {
155 	int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
156 	struct dmi_device *dev;
157 
158 	for (i = 0; i < count; i++) {
159 		const char *d = (char *)(dm + 1) + (i * 2);
160 
161 		/* Skip disabled device */
162 		if ((*d & 0x80) == 0)
163 			continue;
164 
165 		dev = dmi_alloc(sizeof(*dev));
166 		if (!dev) {
167 			printk(KERN_ERR "dmi_save_devices: out of memory.\n");
168 			break;
169 		}
170 
171 		dev->type = *d++ & 0x7f;
172 		dev->name = dmi_string(dm, *d);
173 		dev->device_data = NULL;
174 		list_add(&dev->list, &dmi_devices);
175 	}
176 }
177 
178 static void __init dmi_save_oem_strings_devices(const struct dmi_header *dm)
179 {
180 	int i, count = *(u8 *)(dm + 1);
181 	struct dmi_device *dev;
182 
183 	for (i = 1; i <= count; i++) {
184 		dev = dmi_alloc(sizeof(*dev));
185 		if (!dev) {
186 			printk(KERN_ERR
187 			   "dmi_save_oem_strings_devices: out of memory.\n");
188 			break;
189 		}
190 
191 		dev->type = DMI_DEV_TYPE_OEM_STRING;
192 		dev->name = dmi_string(dm, i);
193 		dev->device_data = NULL;
194 
195 		list_add(&dev->list, &dmi_devices);
196 	}
197 }
198 
199 static void __init dmi_save_ipmi_device(const struct dmi_header *dm)
200 {
201 	struct dmi_device *dev;
202 	void * data;
203 
204 	data = dmi_alloc(dm->length);
205 	if (data == NULL) {
206 		printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
207 		return;
208 	}
209 
210 	memcpy(data, dm, dm->length);
211 
212 	dev = dmi_alloc(sizeof(*dev));
213 	if (!dev) {
214 		printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
215 		return;
216 	}
217 
218 	dev->type = DMI_DEV_TYPE_IPMI;
219 	dev->name = "IPMI controller";
220 	dev->device_data = data;
221 
222 	list_add(&dev->list, &dmi_devices);
223 }
224 
225 /*
226  *	Process a DMI table entry. Right now all we care about are the BIOS
227  *	and machine entries. For 2.5 we should pull the smbus controller info
228  *	out of here.
229  */
230 static void __init dmi_decode(const struct dmi_header *dm)
231 {
232 	switch(dm->type) {
233 	case 0:		/* BIOS Information */
234 		dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
235 		dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
236 		dmi_save_ident(dm, DMI_BIOS_DATE, 8);
237 		break;
238 	case 1:		/* System Information */
239 		dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
240 		dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
241 		dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
242 		dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
243 		dmi_save_uuid(dm, DMI_PRODUCT_UUID, 8);
244 		break;
245 	case 2:		/* Base Board Information */
246 		dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
247 		dmi_save_ident(dm, DMI_BOARD_NAME, 5);
248 		dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
249 		dmi_save_ident(dm, DMI_BOARD_SERIAL, 7);
250 		dmi_save_ident(dm, DMI_BOARD_ASSET_TAG, 8);
251 		break;
252 	case 3:		/* Chassis Information */
253 		dmi_save_ident(dm, DMI_CHASSIS_VENDOR, 4);
254 		dmi_save_type(dm, DMI_CHASSIS_TYPE, 5);
255 		dmi_save_ident(dm, DMI_CHASSIS_VERSION, 6);
256 		dmi_save_ident(dm, DMI_CHASSIS_SERIAL, 7);
257 		dmi_save_ident(dm, DMI_CHASSIS_ASSET_TAG, 8);
258 		break;
259 	case 10:	/* Onboard Devices Information */
260 		dmi_save_devices(dm);
261 		break;
262 	case 11:	/* OEM Strings */
263 		dmi_save_oem_strings_devices(dm);
264 		break;
265 	case 38:	/* IPMI Device Information */
266 		dmi_save_ipmi_device(dm);
267 	}
268 }
269 
270 static int __init dmi_present(const char __iomem *p)
271 {
272 	u8 buf[15];
273 
274 	memcpy_fromio(buf, p, 15);
275 	if ((memcmp(buf, "_DMI_", 5) == 0) && dmi_checksum(buf)) {
276 		u16 num = (buf[13] << 8) | buf[12];
277 		u16 len = (buf[7] << 8) | buf[6];
278 		u32 base = (buf[11] << 24) | (buf[10] << 16) |
279 			(buf[9] << 8) | buf[8];
280 
281 		/*
282 		 * DMI version 0.0 means that the real version is taken from
283 		 * the SMBIOS version, which we don't know at this point.
284 		 */
285 		if (buf[14] != 0)
286 			printk(KERN_INFO "DMI %d.%d present.\n",
287 			       buf[14] >> 4, buf[14] & 0xF);
288 		else
289 			printk(KERN_INFO "DMI present.\n");
290 		if (dmi_table(base,len, num, dmi_decode) == 0)
291 			return 0;
292 	}
293 	return 1;
294 }
295 
296 void __init dmi_scan_machine(void)
297 {
298 	char __iomem *p, *q;
299 	int rc;
300 
301 	if (efi_enabled) {
302 		if (efi.smbios == EFI_INVALID_TABLE_ADDR)
303 			goto out;
304 
305 		/* This is called as a core_initcall() because it isn't
306 		 * needed during early boot.  This also means we can
307 		 * iounmap the space when we're done with it.
308 		 */
309 		p = dmi_ioremap(efi.smbios, 32);
310 		if (p == NULL)
311 			goto out;
312 
313 		rc = dmi_present(p + 0x10); /* offset of _DMI_ string */
314 		dmi_iounmap(p, 32);
315 		if (!rc) {
316 			dmi_available = 1;
317 			return;
318 		}
319 	}
320 	else {
321 		/*
322 		 * no iounmap() for that ioremap(); it would be a no-op, but
323 		 * it's so early in setup that sucker gets confused into doing
324 		 * what it shouldn't if we actually call it.
325 		 */
326 		p = dmi_ioremap(0xF0000, 0x10000);
327 		if (p == NULL)
328 			goto out;
329 
330 		for (q = p; q < p + 0x10000; q += 16) {
331 			rc = dmi_present(q);
332 			if (!rc) {
333 				dmi_available = 1;
334 				return;
335 			}
336 		}
337 	}
338  out:	printk(KERN_INFO "DMI not present or invalid.\n");
339 }
340 
341 /**
342  *	dmi_check_system - check system DMI data
343  *	@list: array of dmi_system_id structures to match against
344  *		All non-null elements of the list must match
345  *		their slot's (field index's) data (i.e., each
346  *		list string must be a substring of the specified
347  *		DMI slot's string data) to be considered a
348  *		successful match.
349  *
350  *	Walk the blacklist table running matching functions until someone
351  *	returns non zero or we hit the end. Callback function is called for
352  *	each successful match. Returns the number of matches.
353  */
354 int dmi_check_system(const struct dmi_system_id *list)
355 {
356 	int i, count = 0;
357 	const struct dmi_system_id *d = list;
358 
359 	while (d->ident) {
360 		for (i = 0; i < ARRAY_SIZE(d->matches); i++) {
361 			int s = d->matches[i].slot;
362 			if (s == DMI_NONE)
363 				continue;
364 			if (dmi_ident[s] && strstr(dmi_ident[s], d->matches[i].substr))
365 				continue;
366 			/* No match */
367 			goto fail;
368 		}
369 		count++;
370 		if (d->callback && d->callback(d))
371 			break;
372 fail:		d++;
373 	}
374 
375 	return count;
376 }
377 EXPORT_SYMBOL(dmi_check_system);
378 
379 /**
380  *	dmi_get_system_info - return DMI data value
381  *	@field: data index (see enum dmi_field)
382  *
383  *	Returns one DMI data value, can be used to perform
384  *	complex DMI data checks.
385  */
386 const char *dmi_get_system_info(int field)
387 {
388 	return dmi_ident[field];
389 }
390 EXPORT_SYMBOL(dmi_get_system_info);
391 
392 
393 /**
394  *	dmi_name_in_vendors - Check if string is anywhere in the DMI vendor information.
395  *	@str: 	Case sensitive Name
396  */
397 int dmi_name_in_vendors(const char *str)
398 {
399 	static int fields[] = { DMI_BIOS_VENDOR, DMI_BIOS_VERSION, DMI_SYS_VENDOR,
400 				DMI_PRODUCT_NAME, DMI_PRODUCT_VERSION, DMI_BOARD_VENDOR,
401 				DMI_BOARD_NAME, DMI_BOARD_VERSION, DMI_NONE };
402 	int i;
403 	for (i = 0; fields[i] != DMI_NONE; i++) {
404 		int f = fields[i];
405 		if (dmi_ident[f] && strstr(dmi_ident[f], str))
406 			return 1;
407 	}
408 	return 0;
409 }
410 EXPORT_SYMBOL(dmi_name_in_vendors);
411 
412 /**
413  *	dmi_find_device - find onboard device by type/name
414  *	@type: device type or %DMI_DEV_TYPE_ANY to match all device types
415  *	@name: device name string or %NULL to match all
416  *	@from: previous device found in search, or %NULL for new search.
417  *
418  *	Iterates through the list of known onboard devices. If a device is
419  *	found with a matching @vendor and @device, a pointer to its device
420  *	structure is returned.  Otherwise, %NULL is returned.
421  *	A new search is initiated by passing %NULL as the @from argument.
422  *	If @from is not %NULL, searches continue from next device.
423  */
424 const struct dmi_device * dmi_find_device(int type, const char *name,
425 				    const struct dmi_device *from)
426 {
427 	const struct list_head *head = from ? &from->list : &dmi_devices;
428 	struct list_head *d;
429 
430 	for(d = head->next; d != &dmi_devices; d = d->next) {
431 		const struct dmi_device *dev =
432 			list_entry(d, struct dmi_device, list);
433 
434 		if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
435 		    ((name == NULL) || (strcmp(dev->name, name) == 0)))
436 			return dev;
437 	}
438 
439 	return NULL;
440 }
441 EXPORT_SYMBOL(dmi_find_device);
442 
443 /**
444  *	dmi_get_year - Return year of a DMI date
445  *	@field:	data index (like dmi_get_system_info)
446  *
447  *	Returns -1 when the field doesn't exist. 0 when it is broken.
448  */
449 int dmi_get_year(int field)
450 {
451 	int year;
452 	const char *s = dmi_get_system_info(field);
453 
454 	if (!s)
455 		return -1;
456 	if (*s == '\0')
457 		return 0;
458 	s = strrchr(s, '/');
459 	if (!s)
460 		return 0;
461 
462 	s += 1;
463 	year = simple_strtoul(s, NULL, 0);
464 	if (year && year < 100) {	/* 2-digit year */
465 		year += 1900;
466 		if (year < 1996)	/* no dates < spec 1.0 */
467 			year += 100;
468 	}
469 
470 	return year;
471 }
472 
473