release/src-rt-6.x/linux/linux-2.6/arch/sparc/kernel/prom.c

   1 /*
   2  * Procedures for creating, accessing and interpreting the device tree.
   3  *
   4  * Paul Mackerras       August 1996.
   5  * Copyright (C) 1996-2005 Paul Mackerras.
   6  *
   7  *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
   8  *    {engebret|bergner}@us.ibm.com
   9  *
  10  *  Adapted for sparc32 by David S. Miller davem@davemloft.net
  11  *
  12  *      This program is free software; you can redistribute it and/or
  13  *      modify it under the terms of the GNU General Public License
  14  *      as published by the Free Software Foundation; either version
  15  *      2 of the License, or (at your option) any later version.
  16  */
  17
  18 #include <linux/kernel.h>
  19 #include <linux/types.h>
  20 #include <linux/string.h>
  21 #include <linux/mm.h>
  22 #include <linux/bootmem.h>
  23 #include <linux/module.h>
  24
  25 #include <asm/prom.h>
  26 #include <asm/oplib.h>
  27
  28 static struct device_node *allnodes;
  29
  30 /* use when traversing tree through the allnext, child, sibling,
  31  * or parent members of struct device_node.
  32  */
  33 static DEFINE_RWLOCK(devtree_lock);
  34
  35 int of_device_is_compatible(const struct device_node *device,
  36                             const char *compat)
  37 {
  38         const char* cp;
  39         int cplen, l;
  40
  41         cp = of_get_property(device, "compatible", &cplen);
  42         if (cp == NULL)
  43                 return 0;
  44         while (cplen > 0) {
  45                 if (strncmp(cp, compat, strlen(compat)) == 0)
  46                         return 1;
  47                 l = strlen(cp) + 1;
  48                 cp += l;
  49                 cplen -= l;
  50         }
  51
  52         return 0;
  53 }
  54 EXPORT_SYMBOL(of_device_is_compatible);
  55
  56 struct device_node *of_get_parent(const struct device_node *node)
  57 {
  58         struct device_node *np;
  59
  60         if (!node)
  61                 return NULL;
  62
  63         np = node->parent;
  64
  65         return np;
  66 }
  67 EXPORT_SYMBOL(of_get_parent);
  68
  69 struct device_node *of_get_next_child(const struct device_node *node,
  70         struct device_node *prev)
  71 {
  72         struct device_node *next;
  73
  74         next = prev ? prev->sibling : node->child;
  75         for (; next != 0; next = next->sibling) {
  76                 break;
  77         }
  78
  79         return next;
  80 }
  81 EXPORT_SYMBOL(of_get_next_child);
  82
  83 struct device_node *of_find_node_by_path(const char *path)
  84 {
  85         struct device_node *np = allnodes;
  86
  87         for (; np != 0; np = np->allnext) {
  88                 if (np->full_name != 0 && strcmp(np->full_name, path) == 0)
  89                         break;
  90         }
  91
  92         return np;
  93 }
  94 EXPORT_SYMBOL(of_find_node_by_path);
  95
  96 struct device_node *of_find_node_by_phandle(phandle handle)
  97 {
  98         struct device_node *np;
  99
 100         for (np = allnodes; np != 0; np = np->allnext)
 101                 if (np->node == handle)
 102                         break;
 103
 104         return np;
 105 }
 106 EXPORT_SYMBOL(of_find_node_by_phandle);
 107
 108 struct device_node *of_find_node_by_name(struct device_node *from,
 109         const char *name)
 110 {
 111         struct device_node *np;
 112
 113         np = from ? from->allnext : allnodes;
 114         for (; np != NULL; np = np->allnext)
 115                 if (np->name != NULL && strcmp(np->name, name) == 0)
 116                         break;
 117
 118         return np;
 119 }
 120 EXPORT_SYMBOL(of_find_node_by_name);
 121
 122 struct device_node *of_find_node_by_type(struct device_node *from,
 123         const char *type)
 124 {
 125         struct device_node *np;
 126
 127         np = from ? from->allnext : allnodes;
 128         for (; np != 0; np = np->allnext)
 129                 if (np->type != 0 && strcmp(np->type, type) == 0)
 130                         break;
 131
 132         return np;
 133 }
 134 EXPORT_SYMBOL(of_find_node_by_type);
 135
 136 struct device_node *of_find_compatible_node(struct device_node *from,
 137         const char *type, const char *compatible)
 138 {
 139         struct device_node *np;
 140
 141         np = from ? from->allnext : allnodes;
 142         for (; np != 0; np = np->allnext) {
 143                 if (type != NULL
 144                     && !(np->type != 0 && strcmp(np->type, type) == 0))
 145                         continue;
 146                 if (of_device_is_compatible(np, compatible))
 147                         break;
 148         }
 149
 150         return np;
 151 }
 152 EXPORT_SYMBOL(of_find_compatible_node);
 153
 154 struct property *of_find_property(const struct device_node *np,
 155                                   const char *name,
 156                                   int *lenp)
 157 {
 158         struct property *pp;
 159
 160         for (pp = np->properties; pp != 0; pp = pp->next) {
 161                 if (strcasecmp(pp->name, name) == 0) {
 162                         if (lenp != 0)
 163                                 *lenp = pp->length;
 164                         break;
 165                 }
 166         }
 167         return pp;
 168 }
 169 EXPORT_SYMBOL(of_find_property);
 170
 171 /*
 172  * Find a property with a given name for a given node
 173  * and return the value.
 174  */
 175 const void *of_get_property(const struct device_node *np, const char *name,
 176                             int *lenp)
 177 {
 178         struct property *pp = of_find_property(np,name,lenp);
 179         return pp ? pp->value : NULL;
 180 }
 181 EXPORT_SYMBOL(of_get_property);
 182
 183 int of_getintprop_default(struct device_node *np, const char *name, int def)
 184 {
 185         struct property *prop;
 186         int len;
 187
 188         prop = of_find_property(np, name, &len);
 189         if (!prop || len != 4)
 190                 return def;
 191
 192         return *(int *) prop->value;
 193 }
 194 EXPORT_SYMBOL(of_getintprop_default);
 195
 196 int of_n_addr_cells(struct device_node *np)
 197 {
 198         const int* ip;
 199         do {
 200                 if (np->parent)
 201                         np = np->parent;
 202                 ip = of_get_property(np, "#address-cells", NULL);
 203                 if (ip != NULL)
 204                         return *ip;
 205         } while (np->parent);
 206         /* No #address-cells property for the root node, default to 2 */
 207         return 2;
 208 }
 209 EXPORT_SYMBOL(of_n_addr_cells);
 210
 211 int of_n_size_cells(struct device_node *np)
 212 {
 213         const int* ip;
 214         do {
 215                 if (np->parent)
 216                         np = np->parent;
 217                 ip = of_get_property(np, "#size-cells", NULL);
 218                 if (ip != NULL)
 219                         return *ip;
 220         } while (np->parent);
 221         /* No #size-cells property for the root node, default to 1 */
 222         return 1;
 223 }
 224 EXPORT_SYMBOL(of_n_size_cells);
 225
 226 int of_set_property(struct device_node *dp, const char *name, void *val, int len)
 227 {
 228         struct property **prevp;
 229         void *new_val;
 230         int err;
 231
 232         new_val = kmalloc(len, GFP_KERNEL);
 233         if (!new_val)
 234                 return -ENOMEM;
 235
 236         memcpy(new_val, val, len);
 237
 238         err = -ENODEV;
 239
 240         write_lock(&devtree_lock);
 241         prevp = &dp->properties;
 242         while (*prevp) {
 243                 struct property *prop = *prevp;
 244
 245                 if (!strcasecmp(prop->name, name)) {
 246                         void *old_val = prop->value;
 247                         int ret;
 248
 249                         ret = prom_setprop(dp->node, (char *) name, val, len);
 250                         err = -EINVAL;
 251                         if (ret >= 0) {
 252                                 prop->value = new_val;
 253                                 prop->length = len;
 254
 255                                 if (OF_IS_DYNAMIC(prop))
 256                                         kfree(old_val);
 257
 258                                 OF_MARK_DYNAMIC(prop);
 259
 260                                 err = 0;
 261                         }
 262                         break;
 263                 }
 264                 prevp = &(*prevp)->next;
 265         }
 266         write_unlock(&devtree_lock);
 267
 268         /* XXX Upate procfs if necessary... */
 269
 270         return err;
 271 }
 272 EXPORT_SYMBOL(of_set_property);
 273
 274 static unsigned int prom_early_allocated;
 275
 276 static void * __init prom_early_alloc(unsigned long size)
 277 {
 278         void *ret;
 279
 280         ret = __alloc_bootmem(size, SMP_CACHE_BYTES, 0UL);
 281         if (ret != NULL)
 282                 memset(ret, 0, size);
 283
 284         prom_early_allocated += size;
 285
 286         return ret;
 287 }
 288
 289 static int is_root_node(const struct device_node *dp)
 290 {
 291         if (!dp)
 292                 return 0;
 293
 294         return (dp->parent == NULL);
 295 }
 296
 297 /* The following routines deal with the black magic of fully naming a
 298  * node.
 299  *
 300  * Certain well known named nodes are just the simple name string.
 301  *
 302  * Actual devices have an address specifier appended to the base name
 303  * string, like this "foo@addr".  The "addr" can be in any number of
 304  * formats, and the platform plus the type of the node determine the
 305  * format and how it is constructed.
 306  *
 307  * For children of the ROOT node, the naming convention is fixed and
 308  * determined by whether this is a sun4u or sun4v system.
 309  *
 310  * For children of other nodes, it is bus type specific.  So
 311  * we walk up the tree until we discover a "device_type" property
 312  * we recognize and we go from there.
 313  */
 314 static void __init sparc32_path_component(struct device_node *dp, char *tmp_buf)
 315 {
 316         struct linux_prom_registers *regs;
 317         struct property *rprop;
 318
 319         rprop = of_find_property(dp, "reg", NULL);
 320         if (!rprop)
 321                 return;
 322
 323         regs = rprop->value;
 324         sprintf(tmp_buf, "%s@%x,%x",
 325                 dp->name,
 326                 regs->which_io, regs->phys_addr);
 327 }
 328
 329 /* "name@slot,offset"  */
 330 static void __init sbus_path_component(struct device_node *dp, char *tmp_buf)
 331 {
 332         struct linux_prom_registers *regs;
 333         struct property *prop;
 334
 335         prop = of_find_property(dp, "reg", NULL);
 336         if (!prop)
 337                 return;
 338
 339         regs = prop->value;
 340         sprintf(tmp_buf, "%s@%x,%x",
 341                 dp->name,
 342                 regs->which_io,
 343                 regs->phys_addr);
 344 }
 345
 346 /* "name@devnum[,func]" */
 347 static void __init pci_path_component(struct device_node *dp, char *tmp_buf)
 348 {
 349         struct linux_prom_pci_registers *regs;
 350         struct property *prop;
 351         unsigned int devfn;
 352
 353         prop = of_find_property(dp, "reg", NULL);
 354         if (!prop)
 355                 return;
 356
 357         regs = prop->value;
 358         devfn = (regs->phys_hi >> 8) & 0xff;
 359         if (devfn & 0x07) {
 360                 sprintf(tmp_buf, "%s@%x,%x",
 361                         dp->name,
 362                         devfn >> 3,
 363                         devfn & 0x07);
 364         } else {
 365                 sprintf(tmp_buf, "%s@%x",
 366                         dp->name,
 367                         devfn >> 3);
 368         }
 369 }
 370
 371 /* "name@addrhi,addrlo" */
 372 static void __init ebus_path_component(struct device_node *dp, char *tmp_buf)
 373 {
 374         struct linux_prom_registers *regs;
 375         struct property *prop;
 376
 377         prop = of_find_property(dp, "reg", NULL);
 378         if (!prop)
 379                 return;
 380
 381         regs = prop->value;
 382
 383         sprintf(tmp_buf, "%s@%x,%x",
 384                 dp->name,
 385                 regs->which_io, regs->phys_addr);
 386 }
 387
 388 static void __init __build_path_component(struct device_node *dp, char *tmp_buf)
 389 {
 390         struct device_node *parent = dp->parent;
 391
 392         if (parent != NULL) {
 393                 if (!strcmp(parent->type, "pci") ||
 394                     !strcmp(parent->type, "pciex"))
 395                         return pci_path_component(dp, tmp_buf);
 396                 if (!strcmp(parent->type, "sbus"))
 397                         return sbus_path_component(dp, tmp_buf);
 398                 if (!strcmp(parent->type, "ebus"))
 399                         return ebus_path_component(dp, tmp_buf);
 400
 401                 /* "isa" is handled with platform naming */
 402         }
 403
 404         /* Use platform naming convention.  */
 405         return sparc32_path_component(dp, tmp_buf);
 406 }
 407
 408 static char * __init build_path_component(struct device_node *dp)
 409 {
 410         char tmp_buf[64], *n;
 411
 412         tmp_buf[0] = '\0';
 413         __build_path_component(dp, tmp_buf);
 414         if (tmp_buf[0] == '\0')
 415                 strcpy(tmp_buf, dp->name);
 416
 417         n = prom_early_alloc(strlen(tmp_buf) + 1);
 418         strcpy(n, tmp_buf);
 419
 420         return n;
 421 }
 422
 423 static char * __init build_full_name(struct device_node *dp)
 424 {
 425         int len, ourlen, plen;
 426         char *n;
 427
 428         plen = strlen(dp->parent->full_name);
 429         ourlen = strlen(dp->path_component_name);
 430         len = ourlen + plen + 2;
 431
 432         n = prom_early_alloc(len);
 433         strcpy(n, dp->parent->full_name);
 434         if (!is_root_node(dp->parent)) {
 435                 strcpy(n + plen, "/");
 436                 plen++;
 437         }
 438         strcpy(n + plen, dp->path_component_name);
 439
 440         return n;
 441 }
 442
 443 static unsigned int unique_id;
 444
 445 static struct property * __init build_one_prop(phandle node, char *prev, char *special_name, void *special_val, int special_len)
 446 {
 447         static struct property *tmp = NULL;
 448         struct property *p;
 449         int len;
 450         const char *name;
 451
 452         if (tmp) {
 453                 p = tmp;
 454                 memset(p, 0, sizeof(*p) + 32);
 455                 tmp = NULL;
 456         } else {
 457                 p = prom_early_alloc(sizeof(struct property) + 32);
 458                 p->unique_id = unique_id++;
 459         }
 460
 461         p->name = (char *) (p + 1);
 462         if (special_name) {
 463                 strcpy(p->name, special_name);
 464                 p->length = special_len;
 465                 p->value = prom_early_alloc(special_len);
 466                 memcpy(p->value, special_val, special_len);
 467         } else {
 468                 if (prev == NULL) {
 469                         name = prom_firstprop(node, NULL);
 470                 } else {
 471                         name = prom_nextprop(node, prev, NULL);
 472                 }
 473                 if (strlen(name) == 0) {
 474                         tmp = p;
 475                         return NULL;
 476                 }
 477                 strcpy(p->name, name);
 478                 p->length = prom_getproplen(node, p->name);
 479                 if (p->length <= 0) {
 480                         p->length = 0;
 481                 } else {
 482                         p->value = prom_early_alloc(p->length + 1);
 483                         len = prom_getproperty(node, p->name, p->value,
 484                                                p->length);
 485                         if (len <= 0)
 486                                 p->length = 0;
 487                         ((unsigned char *)p->value)[p->length] = '\0';
 488                 }
 489         }
 490         return p;
 491 }
 492
 493 static struct property * __init build_prop_list(phandle node)
 494 {
 495         struct property *head, *tail;
 496
 497         head = tail = build_one_prop(node, NULL,
 498                                      ".node", &node, sizeof(node));
 499
 500         tail->next = build_one_prop(node, NULL, NULL, NULL, 0);
 501         tail = tail->next;
 502         while(tail) {
 503                 tail->next = build_one_prop(node, tail->name,
 504                                             NULL, NULL, 0);
 505                 tail = tail->next;
 506         }
 507
 508         return head;
 509 }
 510
 511 static char * __init get_one_property(phandle node, char *name)
 512 {
 513         char *buf = "<NULL>";
 514         int len;
 515
 516         len = prom_getproplen(node, name);
 517         if (len > 0) {
 518                 buf = prom_early_alloc(len);
 519                 len = prom_getproperty(node, name, buf, len);
 520         }
 521
 522         return buf;
 523 }
 524
 525 static struct device_node * __init create_node(phandle node)
 526 {
 527         struct device_node *dp;
 528
 529         if (!node)
 530                 return NULL;
 531
 532         dp = prom_early_alloc(sizeof(*dp));
 533         dp->unique_id = unique_id++;
 534
 535         kref_init(&dp->kref);
 536
 537         dp->name = get_one_property(node, "name");
 538         dp->type = get_one_property(node, "device_type");
 539         dp->node = node;
 540
 541         /* Build interrupts later... */
 542
 543         dp->properties = build_prop_list(node);
 544
 545         return dp;
 546 }
 547
 548 static struct device_node * __init build_tree(struct device_node *parent, phandle node, struct device_node ***nextp)
 549 {
 550         struct device_node *dp;
 551
 552         dp = create_node(node);
 553         if (dp) {
 554                 *(*nextp) = dp;
 555                 *nextp = &dp->allnext;
 556
 557                 dp->parent = parent;
 558                 dp->path_component_name = build_path_component(dp);
 559                 dp->full_name = build_full_name(dp);
 560
 561                 dp->child = build_tree(dp, prom_getchild(node), nextp);
 562
 563                 dp->sibling = build_tree(parent, prom_getsibling(node), nextp);
 564         }
 565
 566         return dp;
 567 }
 568
 569 void __init prom_build_devicetree(void)
 570 {
 571         struct device_node **nextp;
 572
 573         allnodes = create_node(prom_root_node);
 574         allnodes->path_component_name = "";
 575         allnodes->full_name = "/";
 576
 577         nextp = &allnodes->allnext;
 578         allnodes->child = build_tree(allnodes,
 579                                      prom_getchild(allnodes->node),
 580                                      &nextp);
 581         printk("PROM: Built device tree with %u bytes of memory.\n",
 582                prom_early_allocated);
 583 }