dmi_scan.c revision ebad6a4230bdb5927495e28bc7837f515bf667a7 
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/bootmem.h>
7
8
9static char * __init dmi_string(struct dmi_header *dm, u8 s)
10{
11	u8 *bp = ((u8 *) dm) + dm->length;
12	char *str = "";
13
14	if (s) {
15		s--;
16		while (s > 0 && *bp) {
17			bp += strlen(bp) + 1;
18			s--;
19		}
20
21		if (*bp != 0) {
22			str = alloc_bootmem(strlen(bp) + 1);
23			if (str != NULL)
24				strcpy(str, bp);
25			else
26				printk(KERN_ERR "dmi_string: out of memory.\n");
27		}
28 	}
29
30	return str;
31}
32
33/*
34 *	We have to be cautious here. We have seen BIOSes with DMI pointers
35 *	pointing to completely the wrong place for example
36 */
37static int __init dmi_table(u32 base, int len, int num,
38			    void (*decode)(struct dmi_header *))
39{
40	u8 *buf, *data;
41	int i = 0;
42
43	buf = bt_ioremap(base, len);
44	if (buf == NULL)
45		return -1;
46
47	data = buf;
48
49	/*
50 	 *	Stop when we see all the items the table claimed to have
51 	 *	OR we run off the end of the table (also happens)
52 	 */
53	while ((i < num) && (data - buf + sizeof(struct dmi_header)) <= len) {
54		struct dmi_header *dm = (struct dmi_header *)data;
55		/*
56		 *  We want to know the total length (formated area and strings)
57		 *  before decoding to make sure we won't run off the table in
58		 *  dmi_decode or dmi_string
59		 */
60		data += dm->length;
61		while ((data - buf < len - 1) && (data[0] || data[1]))
62			data++;
63		if (data - buf < len - 1)
64			decode(dm);
65		data += 2;
66		i++;
67	}
68	bt_iounmap(buf, len);
69	return 0;
70}
71
72static int __init dmi_checksum(u8 *buf)
73{
74	u8 sum = 0;
75	int a;
76
77	for (a = 0; a < 15; a++)
78		sum += buf[a];
79
80	return sum == 0;
81}
82
83static char *dmi_ident[DMI_STRING_MAX];
84static LIST_HEAD(dmi_devices);
85
86/*
87 *	Save a DMI string
88 */
89static void __init dmi_save_ident(struct dmi_header *dm, int slot, int string)
90{
91	char *p, *d = (char*) dm;
92
93	if (dmi_ident[slot])
94		return;
95
96	p = dmi_string(dm, d[string]);
97	if (p == NULL)
98		return;
99
100	dmi_ident[slot] = p;
101}
102
103static void __init dmi_save_devices(struct dmi_header *dm)
104{
105	int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
106	struct dmi_device *dev;
107
108	for (i = 0; i < count; i++) {
109		char *d = ((char *) dm) + (i * 2);
110
111		/* Skip disabled device */
112		if ((*d & 0x80) == 0)
113			continue;
114
115		dev = alloc_bootmem(sizeof(*dev));
116		if (!dev) {
117			printk(KERN_ERR "dmi_save_devices: out of memory.\n");
118			break;
119		}
120
121		dev->type = *d++ & 0x7f;
122		dev->name = dmi_string(dm, *d);
123		dev->device_data = NULL;
124
125		list_add(&dev->list, &dmi_devices);
126	}
127}
128
129static void __init dmi_save_ipmi_device(struct dmi_header *dm)
130{
131	struct dmi_device *dev;
132	void * data;
133
134	data = alloc_bootmem(dm->length);
135	if (data == NULL) {
136		printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
137		return;
138	}
139
140	memcpy(data, dm, dm->length);
141
142	dev = alloc_bootmem(sizeof(*dev));
143	if (!dev) {
144		printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
145		return;
146	}
147
148	dev->type = DMI_DEV_TYPE_IPMI;
149	dev->name = "IPMI controller";
150	dev->device_data = data;
151
152	list_add(&dev->list, &dmi_devices);
153}
154
155/*
156 *	Process a DMI table entry. Right now all we care about are the BIOS
157 *	and machine entries. For 2.5 we should pull the smbus controller info
158 *	out of here.
159 */
160static void __init dmi_decode(struct dmi_header *dm)
161{
162	switch(dm->type) {
163	case 0:		/* BIOS Information */
164		dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
165		dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
166		dmi_save_ident(dm, DMI_BIOS_DATE, 8);
167		break;
168	case 1:		/* System Information */
169		dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
170		dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
171		dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
172		dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
173		break;
174	case 2:		/* Base Board Information */
175		dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
176		dmi_save_ident(dm, DMI_BOARD_NAME, 5);
177		dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
178		break;
179	case 10:	/* Onboard Devices Information */
180		dmi_save_devices(dm);
181		break;
182	case 38:	/* IPMI Device Information */
183		dmi_save_ipmi_device(dm);
184	}
185}
186
187void __init dmi_scan_machine(void)
188{
189	u8 buf[15];
190	char __iomem *p, *q;
191
192	/*
193	 * no iounmap() for that ioremap(); it would be a no-op, but it's
194	 * so early in setup that sucker gets confused into doing what
195	 * it shouldn't if we actually call it.
196	 */
197	p = ioremap(0xF0000, 0x10000);
198	if (p == NULL)
199		goto out;
200
201	for (q = p; q < p + 0x10000; q += 16) {
202		memcpy_fromio(buf, q, 15);
203		if ((memcmp(buf, "_DMI_", 5) == 0) && dmi_checksum(buf)) {
204			u16 num = (buf[13] << 8) | buf[12];
205			u16 len = (buf[7] << 8) | buf[6];
206			u32 base = (buf[11] << 24) | (buf[10] << 16) |
207				   (buf[9] << 8) | buf[8];
208
209			/*
210			 * DMI version 0.0 means that the real version is taken from
211			 * the SMBIOS version, which we don't know at this point.
212			 */
213			if (buf[14] != 0)
214				printk(KERN_INFO "DMI %d.%d present.\n",
215					buf[14] >> 4, buf[14] & 0xF);
216			else
217				printk(KERN_INFO "DMI present.\n");
218
219			if (dmi_table(base,len, num, dmi_decode) == 0)
220				return;
221		}
222	}
223
224out:	printk(KERN_INFO "DMI not present.\n");
225}
226
227
228/**
229 *	dmi_check_system - check system DMI data
230 *	@list: array of dmi_system_id structures to match against
231 *
232 *	Walk the blacklist table running matching functions until someone
233 *	returns non zero or we hit the end. Callback function is called for
234 *	each successfull match. Returns the number of matches.
235 */
236int dmi_check_system(struct dmi_system_id *list)
237{
238	int i, count = 0;
239	struct dmi_system_id *d = list;
240
241	while (d->ident) {
242		for (i = 0; i < ARRAY_SIZE(d->matches); i++) {
243			int s = d->matches[i].slot;
244			if (s == DMI_NONE)
245				continue;
246			if (dmi_ident[s] && strstr(dmi_ident[s], d->matches[i].substr))
247				continue;
248			/* No match */
249			goto fail;
250		}
251		if (d->callback && d->callback(d))
252			break;
253		count++;
254fail:		d++;
255	}
256
257	return count;
258}
259EXPORT_SYMBOL(dmi_check_system);
260
261/**
262 *	dmi_get_system_info - return DMI data value
263 *	@field: data index (see enum dmi_filed)
264 *
265 *	Returns one DMI data value, can be used to perform
266 *	complex DMI data checks.
267 */
268char *dmi_get_system_info(int field)
269{
270	return dmi_ident[field];
271}
272EXPORT_SYMBOL(dmi_get_system_info);
273
274/**
275 *	dmi_find_device - find onboard device by type/name
276 *	@type: device type or %DMI_DEV_TYPE_ANY to match all device types
277 *	@desc: device name string or %NULL to match all
278 *	@from: previous device found in search, or %NULL for new search.
279 *
280 *	Iterates through the list of known onboard devices. If a device is
281 *	found with a matching @vendor and @device, a pointer to its device
282 *	structure is returned.  Otherwise, %NULL is returned.
283 *	A new search is initiated by passing %NULL to the @from argument.
284 *	If @from is not %NULL, searches continue from next device.
285 */
286struct dmi_device * dmi_find_device(int type, const char *name,
287				    struct dmi_device *from)
288{
289	struct list_head *d, *head = from ? &from->list : &dmi_devices;
290
291	for(d = head->next; d != &dmi_devices; d = d->next) {
292		struct dmi_device *dev = list_entry(d, struct dmi_device, list);
293
294		if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
295		    ((name == NULL) || (strcmp(dev->name, name) == 0)))
296			return dev;
297	}
298
299	return NULL;
300}
301EXPORT_SYMBOL(dmi_find_device);
302