drivers/firmware/dmi_scan.c

   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(struct dmi_header *dm, u8 s)
  12 {
  13         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)(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                 struct dmi_header *dm = (struct dmi_header *)data;
  57                 /*
  58                  *  We want to know the total length (formated area and strings)
  59                  *  before decoding to make sure we won't run off the table in
  60                  *  dmi_decode or dmi_string
  61                  */
  62                 data += dm->length;
  63                 while ((data - buf < len - 1) && (data[0] || data[1]))
  64                         data++;
  65                 if (data - buf < len - 1)
  66                         decode(dm);
  67                 data += 2;
  68                 i++;
  69         }
  70         dmi_iounmap(buf, len);
  71         return 0;
  72 }
  73
  74 static int __init dmi_checksum(u8 *buf)
  75 {
  76         u8 sum = 0;
  77         int a;
  78
  79         for (a = 0; a < 15; a++)
  80                 sum += buf[a];
  81
  82         return sum == 0;
  83 }
  84
  85 static char *dmi_ident[DMI_STRING_MAX];
  86 static LIST_HEAD(dmi_devices);
  87
  88 /*
  89  *      Save a DMI string
  90  */
  91 static void __init dmi_save_ident(struct dmi_header *dm, int slot, int string)
  92 {
  93         char *p, *d = (char*) dm;
  94
  95         if (dmi_ident[slot])
  96                 return;
  97
  98         p = dmi_string(dm, d[string]);
  99         if (p == NULL)
 100                 return;
 101
 102         dmi_ident[slot] = p;
 103 }
 104
 105 static void __init dmi_save_devices(struct dmi_header *dm)
 106 {
 107         int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
 108         struct dmi_device *dev;
 109
 110         for (i = 0; i < count; i++) {
 111                 char *d = (char *)(dm + 1) + (i * 2);
 112
 113                 /* Skip disabled device */
 114                 if ((*d & 0x80) == 0)
 115                         continue;
 116
 117                 dev = dmi_alloc(sizeof(*dev));
 118                 if (!dev) {
 119                         printk(KERN_ERR "dmi_save_devices: out of memory.\n");
 120                         break;
 121                 }
 122
 123                 dev->type = *d++ & 0x7f;
 124                 dev->name = dmi_string(dm, *d);
 125                 dev->device_data = NULL;
 126
 127                 list_add(&dev->list, &dmi_devices);
 128         }
 129 }
 130
 131 static void __init dmi_save_ipmi_device(struct dmi_header *dm)
 132 {
 133         struct dmi_device *dev;
 134         void * data;
 135
 136         data = dmi_alloc(dm->length);
 137         if (data == NULL) {
 138                 printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
 139                 return;
 140         }
 141
 142         memcpy(data, dm, dm->length);
 143
 144         dev = dmi_alloc(sizeof(*dev));
 145         if (!dev) {
 146                 printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
 147                 return;
 148         }
 149
 150         dev->type = DMI_DEV_TYPE_IPMI;
 151         dev->name = "IPMI controller";
 152         dev->device_data = data;
 153
 154         list_add(&dev->list, &dmi_devices);
 155 }
 156
 157 /*
 158  *      Process a DMI table entry. Right now all we care about are the BIOS
 159  *      and machine entries. For 2.5 we should pull the smbus controller info
 160  *      out of here.
 161  */
 162 static void __init dmi_decode(struct dmi_header *dm)
 163 {
 164         switch(dm->type) {
 165         case 0:         /* BIOS Information */
 166                 dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
 167                 dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
 168                 dmi_save_ident(dm, DMI_BIOS_DATE, 8);
 169                 break;
 170         case 1:         /* System Information */
 171                 dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
 172                 dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
 173                 dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
 174                 dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
 175                 break;
 176         case 2:         /* Base Board Information */
 177                 dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
 178                 dmi_save_ident(dm, DMI_BOARD_NAME, 5);
 179                 dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
 180                 break;
 181         case 10:        /* Onboard Devices Information */
 182                 dmi_save_devices(dm);
 183                 break;
 184         case 38:        /* IPMI Device Information */
 185                 dmi_save_ipmi_device(dm);
 186         }
 187 }
 188
 189 static int __init dmi_present(char __iomem *p)
 190 {
 191         u8 buf[15];
 192         memcpy_fromio(buf, p, 15);
 193         if ((memcmp(buf, "_DMI_", 5) == 0) && dmi_checksum(buf)) {
 194                 u16 num = (buf[13] << 8) | buf[12];
 195                 u16 len = (buf[7] << 8) | buf[6];
 196                 u32 base = (buf[11] << 24) | (buf[10] << 16) |
 197                         (buf[9] << 8) | buf[8];
 198
 199                 /*
 200                  * DMI version 0.0 means that the real version is taken from
 201                  * the SMBIOS version, which we don't know at this point.
 202                  */
 203                 if (buf[14] != 0)
 204                         printk(KERN_INFO "DMI %d.%d present.\n",
 205                                buf[14] >> 4, buf[14] & 0xF);
 206                 else
 207                         printk(KERN_INFO "DMI present.\n");
 208                 if (dmi_table(base,len, num, dmi_decode) == 0)
 209                         return 0;
 210         }
 211         return 1;
 212 }
 213
 214 void __init dmi_scan_machine(void)
 215 {
 216         char __iomem *p, *q;
 217         int rc;
 218
 219         if (efi_enabled) {
 220                 if (efi.smbios == EFI_INVALID_TABLE_ADDR)
 221                         goto out;
 222
 223                /* This is called as a core_initcall() because it isn't
 224                 * needed during early boot.  This also means we can
 225                 * iounmap the space when we're done with it.
 226                 */
 227                 p = dmi_ioremap(efi.smbios, 32);
 228                 if (p == NULL)
 229                         goto out;
 230
 231                 rc = dmi_present(p + 0x10); /* offset of _DMI_ string */
 232                 dmi_iounmap(p, 32);
 233                 if (!rc)
 234                         return;
 235         }
 236         else {
 237                 /*
 238                  * no iounmap() for that ioremap(); it would be a no-op, but
 239                  * it's so early in setup that sucker gets confused into doing
 240                  * what it shouldn't if we actually call it.
 241                  */
 242                 p = dmi_ioremap(0xF0000, 0x10000);
 243                 if (p == NULL)
 244                         goto out;
 245
 246                 for (q = p; q < p + 0x10000; q += 16) {
 247                         rc = dmi_present(q);
 248                         if (!rc)
 249                                 return;
 250                 }
 251         }
 252  out:   printk(KERN_INFO "DMI not present or invalid.\n");
 253 }
 254
 255 /**
 256  *      dmi_check_system - check system DMI data
 257  *      @list: array of dmi_system_id structures to match against
 258  *              All non-null elements of the list must match
 259  *              their slot's (field index's) data (i.e., each
 260  *              list string must be a substring of the specified
 261  *              DMI slot's string data) to be considered a
 262  *              successful match.
 263  *
 264  *      Walk the blacklist table running matching functions until someone
 265  *      returns non zero or we hit the end. Callback function is called for
 266  *      each successful match. Returns the number of matches.
 267  */
 268 int dmi_check_system(struct dmi_system_id *list)
 269 {
 270         int i, count = 0;
 271         struct dmi_system_id *d = list;
 272
 273         while (d->ident) {
 274                 for (i = 0; i < ARRAY_SIZE(d->matches); i++) {
 275                         int s = d->matches[i].slot;
 276                         if (s == DMI_NONE)
 277                                 continue;
 278                         if (dmi_ident[s] && strstr(dmi_ident[s], d->matches[i].substr))
 279                                 continue;
 280                         /* No match */
 281                         goto fail;
 282                 }
 283                 count++;
 284                 if (d->callback && d->callback(d))
 285                         break;
 286 fail:           d++;
 287         }
 288
 289         return count;
 290 }
 291 EXPORT_SYMBOL(dmi_check_system);
 292
 293 /**
 294  *      dmi_get_system_info - return DMI data value
 295  *      @field: data index (see enum dmi_field)
 296  *
 297  *      Returns one DMI data value, can be used to perform
 298  *      complex DMI data checks.
 299  */
 300 char *dmi_get_system_info(int field)
 301 {
 302         return dmi_ident[field];
 303 }
 304 EXPORT_SYMBOL(dmi_get_system_info);
 305
 306 /**
 307  *      dmi_find_device - find onboard device by type/name
 308  *      @type: device type or %DMI_DEV_TYPE_ANY to match all device types
 309  *      @name: device name string or %NULL to match all
 310  *      @from: previous device found in search, or %NULL for new search.
 311  *
 312  *      Iterates through the list of known onboard devices. If a device is
 313  *      found with a matching @vendor and @device, a pointer to its device
 314  *      structure is returned.  Otherwise, %NULL is returned.
 315  *      A new search is initiated by passing %NULL as the @from argument.
 316  *      If @from is not %NULL, searches continue from next device.
 317  */
 318 struct dmi_device * dmi_find_device(int type, const char *name,
 319                                     struct dmi_device *from)
 320 {
 321         struct list_head *d, *head = from ? &from->list : &dmi_devices;
 322
 323         for(d = head->next; d != &dmi_devices; d = d->next) {
 324                 struct dmi_device *dev = list_entry(d, struct dmi_device, list);
 325
 326                 if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
 327                     ((name == NULL) || (strcmp(dev->name, name) == 0)))
 328                         return dev;
 329         }
 330
 331         return NULL;
 332 }
 333 EXPORT_SYMBOL(dmi_find_device);
 334
 335 /**
 336  *      dmi_get_year - Return year of a DMI date
 337  *      @field: data index (like dmi_get_system_info)
 338  *
 339  *      Returns -1 when the field doesn't exist. 0 when it is broken.
 340  */
 341 int dmi_get_year(int field)
 342 {
 343         int year;
 344         char *s = dmi_get_system_info(field);
 345
 346         if (!s)
 347                 return -1;
 348         if (*s == '\0')
 349                 return 0;
 350         s = strrchr(s, '/');
 351         if (!s)
 352                 return 0;
 353
 354         s += 1;
 355         year = simple_strtoul(s, NULL, 0);
 356         if (year && year < 100) {       /* 2-digit year */
 357                 year += 1900;
 358                 if (year < 1996)        /* no dates < spec 1.0 */
 359                         year += 100;
 360         }
 361
 362         return year;
 363 }