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 extern rwlock_t devtree_lock;   /* temporary while merging */
  31
  32 struct device_node *of_get_parent(const struct device_node *node)
  33 {
  34         struct device_node *np;
  35
  36         if (!node)
  37                 return NULL;
  38
  39         np = node->parent;
  40
  41         return np;
  42 }
  43 EXPORT_SYMBOL(of_get_parent);
  44
  45 struct device_node *of_get_next_child(const struct device_node *node,
  46         struct device_node *prev)
  47 {
  48         struct device_node *next;
  49
  50         next = prev ? prev->sibling : node->child;
  51         for (; next != 0; next = next->sibling) {
  52                 break;
  53         }
  54
  55         return next;
  56 }
  57 EXPORT_SYMBOL(of_get_next_child);
  58
  59 struct device_node *of_find_node_by_path(const char *path)
  60 {
  61         struct device_node *np = allnodes;
  62
  63         for (; np != 0; np = np->allnext) {
  64                 if (np->full_name != 0 && strcmp(np->full_name, path) == 0)
  65                         break;
  66         }
  67
  68         return np;
  69 }
  70 EXPORT_SYMBOL(of_find_node_by_path);
  71
  72 struct device_node *of_find_node_by_phandle(phandle handle)
  73 {
  74         struct device_node *np;
  75
  76         for (np = allnodes; np != 0; np = np->allnext)
  77                 if (np->node == handle)
  78                         break;
  79
  80         return np;
  81 }
  82 EXPORT_SYMBOL(of_find_node_by_phandle);
  83
  84 struct device_node *of_find_node_by_name(struct device_node *from,
  85         const char *name)
  86 {
  87         struct device_node *np;
  88
  89         np = from ? from->allnext : allnodes;
  90         for (; np != NULL; np = np->allnext)
  91                 if (np->name != NULL && strcmp(np->name, name) == 0)
  92                         break;
  93
  94         return np;
  95 }
  96 EXPORT_SYMBOL(of_find_node_by_name);
  97
  98 struct device_node *of_find_node_by_type(struct device_node *from,
  99         const char *type)
 100 {
 101         struct device_node *np;
 102
 103         np = from ? from->allnext : allnodes;
 104         for (; np != 0; np = np->allnext)
 105                 if (np->type != 0 && strcmp(np->type, type) == 0)
 106                         break;
 107
 108         return np;
 109 }
 110 EXPORT_SYMBOL(of_find_node_by_type);
 111
 112 struct device_node *of_find_compatible_node(struct device_node *from,
 113         const char *type, const char *compatible)
 114 {
 115         struct device_node *np;
 116
 117         np = from ? from->allnext : allnodes;
 118         for (; np != 0; np = np->allnext) {
 119                 if (type != NULL
 120                     && !(np->type != 0 && strcmp(np->type, type) == 0))
 121                         continue;
 122                 if (of_device_is_compatible(np, compatible))
 123                         break;
 124         }
 125
 126         return np;
 127 }
 128 EXPORT_SYMBOL(of_find_compatible_node);
 129
 130 int of_getintprop_default(struct device_node *np, const char *name, int def)
 131 {
 132         struct property *prop;
 133         int len;
 134
 135         prop = of_find_property(np, name, &len);
 136         if (!prop || len != 4)
 137                 return def;
 138
 139         return *(int *) prop->value;
 140 }
 141 EXPORT_SYMBOL(of_getintprop_default);
 142
 143 int of_set_property(struct device_node *dp, const char *name, void *val, int len)
 144 {
 145         struct property **prevp;
 146         void *new_val;
 147         int err;
 148
 149         new_val = kmalloc(len, GFP_KERNEL);
 150         if (!new_val)
 151                 return -ENOMEM;
 152
 153         memcpy(new_val, val, len);
 154
 155         err = -ENODEV;
 156
 157         write_lock(&devtree_lock);
 158         prevp = &dp->properties;
 159         while (*prevp) {
 160                 struct property *prop = *prevp;
 161
 162                 if (!strcasecmp(prop->name, name)) {
 163                         void *old_val = prop->value;
 164                         int ret;
 165
 166                         ret = prom_setprop(dp->node, (char *) name, val, len);
 167                         err = -EINVAL;
 168                         if (ret >= 0) {
 169                                 prop->value = new_val;
 170                                 prop->length = len;
 171
 172                                 if (OF_IS_DYNAMIC(prop))
 173                                         kfree(old_val);
 174
 175                                 OF_MARK_DYNAMIC(prop);
 176
 177                                 err = 0;
 178                         }
 179                         break;
 180                 }
 181                 prevp = &(*prevp)->next;
 182         }
 183         write_unlock(&devtree_lock);
 184
 185         /* XXX Upate procfs if necessary... */
 186
 187         return err;
 188 }
 189 EXPORT_SYMBOL(of_set_property);
 190
 191 static unsigned int prom_early_allocated;
 192
 193 static void * __init prom_early_alloc(unsigned long size)
 194 {
 195         void *ret;
 196
 197         ret = __alloc_bootmem(size, SMP_CACHE_BYTES, 0UL);
 198         if (ret != NULL)
 199                 memset(ret, 0, size);
 200
 201         prom_early_allocated += size;
 202
 203         return ret;
 204 }
 205
 206 static int is_root_node(const struct device_node *dp)
 207 {
 208         if (!dp)
 209                 return 0;
 210
 211         return (dp->parent == NULL);
 212 }
 213
 214 /* The following routines deal with the black magic of fully naming a
 215  * node.
 216  *
 217  * Certain well known named nodes are just the simple name string.
 218  *
 219  * Actual devices have an address specifier appended to the base name
 220  * string, like this "foo@addr".  The "addr" can be in any number of
 221  * formats, and the platform plus the type of the node determine the
 222  * format and how it is constructed.
 223  *
 224  * For children of the ROOT node, the naming convention is fixed and
 225  * determined by whether this is a sun4u or sun4v system.
 226  *
 227  * For children of other nodes, it is bus type specific.  So
 228  * we walk up the tree until we discover a "device_type" property
 229  * we recognize and we go from there.
 230  */
 231 static void __init sparc32_path_component(struct device_node *dp, char *tmp_buf)
 232 {
 233         struct linux_prom_registers *regs;
 234         struct property *rprop;
 235
 236         rprop = of_find_property(dp, "reg", NULL);
 237         if (!rprop)
 238                 return;
 239
 240         regs = rprop->value;
 241         sprintf(tmp_buf, "%s@%x,%x",
 242                 dp->name,
 243                 regs->which_io, regs->phys_addr);
 244 }
 245
 246 /* "name@slot,offset"  */
 247 static void __init sbus_path_component(struct device_node *dp, char *tmp_buf)
 248 {
 249         struct linux_prom_registers *regs;
 250         struct property *prop;
 251
 252         prop = of_find_property(dp, "reg", NULL);
 253         if (!prop)
 254                 return;
 255
 256         regs = prop->value;
 257         sprintf(tmp_buf, "%s@%x,%x",
 258                 dp->name,
 259                 regs->which_io,
 260                 regs->phys_addr);
 261 }
 262
 263 /* "name@devnum[,func]" */
 264 static void __init pci_path_component(struct device_node *dp, char *tmp_buf)
 265 {
 266         struct linux_prom_pci_registers *regs;
 267         struct property *prop;
 268         unsigned int devfn;
 269
 270         prop = of_find_property(dp, "reg", NULL);
 271         if (!prop)
 272                 return;
 273
 274         regs = prop->value;
 275         devfn = (regs->phys_hi >> 8) & 0xff;
 276         if (devfn & 0x07) {
 277                 sprintf(tmp_buf, "%s@%x,%x",
 278                         dp->name,
 279                         devfn >> 3,
 280                         devfn & 0x07);
 281         } else {
 282                 sprintf(tmp_buf, "%s@%x",
 283                         dp->name,
 284                         devfn >> 3);
 285         }
 286 }
 287
 288 /* "name@addrhi,addrlo" */
 289 static void __init ebus_path_component(struct device_node *dp, char *tmp_buf)
 290 {
 291         struct linux_prom_registers *regs;
 292         struct property *prop;
 293
 294         prop = of_find_property(dp, "reg", NULL);
 295         if (!prop)
 296                 return;
 297
 298         regs = prop->value;
 299
 300         sprintf(tmp_buf, "%s@%x,%x",
 301                 dp->name,
 302                 regs->which_io, regs->phys_addr);
 303 }
 304
 305 static void __init __build_path_component(struct device_node *dp, char *tmp_buf)
 306 {
 307         struct device_node *parent = dp->parent;
 308
 309         if (parent != NULL) {
 310                 if (!strcmp(parent->type, "pci") ||
 311                     !strcmp(parent->type, "pciex"))
 312                         return pci_path_component(dp, tmp_buf);
 313                 if (!strcmp(parent->type, "sbus"))
 314                         return sbus_path_component(dp, tmp_buf);
 315                 if (!strcmp(parent->type, "ebus"))
 316                         return ebus_path_component(dp, tmp_buf);
 317
 318                 /* "isa" is handled with platform naming */
 319         }
 320
 321         /* Use platform naming convention.  */
 322         return sparc32_path_component(dp, tmp_buf);
 323 }
 324
 325 static char * __init build_path_component(struct device_node *dp)
 326 {
 327         char tmp_buf[64], *n;
 328
 329         tmp_buf[0] = '\0';
 330         __build_path_component(dp, tmp_buf);
 331         if (tmp_buf[0] == '\0')
 332                 strcpy(tmp_buf, dp->name);
 333
 334         n = prom_early_alloc(strlen(tmp_buf) + 1);
 335         strcpy(n, tmp_buf);
 336
 337         return n;
 338 }
 339
 340 static char * __init build_full_name(struct device_node *dp)
 341 {
 342         int len, ourlen, plen;
 343         char *n;
 344
 345         plen = strlen(dp->parent->full_name);
 346         ourlen = strlen(dp->path_component_name);
 347         len = ourlen + plen + 2;
 348
 349         n = prom_early_alloc(len);
 350         strcpy(n, dp->parent->full_name);
 351         if (!is_root_node(dp->parent)) {
 352                 strcpy(n + plen, "/");
 353                 plen++;
 354         }
 355         strcpy(n + plen, dp->path_component_name);
 356
 357         return n;
 358 }
 359
 360 static unsigned int unique_id;
 361
 362 static struct property * __init build_one_prop(phandle node, char *prev, char *special_name, void *special_val, int special_len)
 363 {
 364         static struct property *tmp = NULL;
 365         struct property *p;
 366         int len;
 367         const char *name;
 368
 369         if (tmp) {
 370                 p = tmp;
 371                 memset(p, 0, sizeof(*p) + 32);
 372                 tmp = NULL;
 373         } else {
 374                 p = prom_early_alloc(sizeof(struct property) + 32);
 375                 p->unique_id = unique_id++;
 376         }
 377
 378         p->name = (char *) (p + 1);
 379         if (special_name) {
 380                 strcpy(p->name, special_name);
 381                 p->length = special_len;
 382                 p->value = prom_early_alloc(special_len);
 383                 memcpy(p->value, special_val, special_len);
 384         } else {
 385                 if (prev == NULL) {
 386                         name = prom_firstprop(node, NULL);
 387                 } else {
 388                         name = prom_nextprop(node, prev, NULL);
 389                 }
 390                 if (strlen(name) == 0) {
 391                         tmp = p;
 392                         return NULL;
 393                 }
 394                 strcpy(p->name, name);
 395                 p->length = prom_getproplen(node, p->name);
 396                 if (p->length <= 0) {
 397                         p->length = 0;
 398                 } else {
 399                         p->value = prom_early_alloc(p->length + 1);
 400                         len = prom_getproperty(node, p->name, p->value,
 401                                                p->length);
 402                         if (len <= 0)
 403                                 p->length = 0;
 404                         ((unsigned char *)p->value)[p->length] = '\0';
 405                 }
 406         }
 407         return p;
 408 }
 409
 410 static struct property * __init build_prop_list(phandle node)
 411 {
 412         struct property *head, *tail;
 413
 414         head = tail = build_one_prop(node, NULL,
 415                                      ".node", &node, sizeof(node));
 416
 417         tail->next = build_one_prop(node, NULL, NULL, NULL, 0);
 418         tail = tail->next;
 419         while(tail) {
 420                 tail->next = build_one_prop(node, tail->name,
 421                                             NULL, NULL, 0);
 422                 tail = tail->next;
 423         }
 424
 425         return head;
 426 }
 427
 428 static char * __init get_one_property(phandle node, char *name)
 429 {
 430         char *buf = "<NULL>";
 431         int len;
 432
 433         len = prom_getproplen(node, name);
 434         if (len > 0) {
 435                 buf = prom_early_alloc(len);
 436                 len = prom_getproperty(node, name, buf, len);
 437         }
 438
 439         return buf;
 440 }
 441
 442 static struct device_node * __init create_node(phandle node)
 443 {
 444         struct device_node *dp;
 445
 446         if (!node)
 447                 return NULL;
 448
 449         dp = prom_early_alloc(sizeof(*dp));
 450         dp->unique_id = unique_id++;
 451
 452         kref_init(&dp->kref);
 453
 454         dp->name = get_one_property(node, "name");
 455         dp->type = get_one_property(node, "device_type");
 456         dp->node = node;
 457
 458         /* Build interrupts later... */
 459
 460         dp->properties = build_prop_list(node);
 461
 462         return dp;
 463 }
 464
 465 static struct device_node * __init build_tree(struct device_node *parent, phandle node, struct device_node ***nextp)
 466 {
 467         struct device_node *dp;
 468
 469         dp = create_node(node);
 470         if (dp) {
 471                 *(*nextp) = dp;
 472                 *nextp = &dp->allnext;
 473
 474                 dp->parent = parent;
 475                 dp->path_component_name = build_path_component(dp);
 476                 dp->full_name = build_full_name(dp);
 477
 478                 dp->child = build_tree(dp, prom_getchild(node), nextp);
 479
 480                 dp->sibling = build_tree(parent, prom_getsibling(node), nextp);
 481         }
 482
 483         return dp;
 484 }
 485
 486 void __init prom_build_devicetree(void)
 487 {
 488         struct device_node **nextp;
 489
 490         allnodes = create_node(prom_root_node);
 491         allnodes->path_component_name = "";
 492         allnodes->full_name = "/";
 493
 494         nextp = &allnodes->allnext;
 495         allnodes->child = build_tree(allnodes,
 496                                      prom_getchild(allnodes->node),
 497                                      &nextp);
 498         printk("PROM: Built device tree with %u bytes of memory.\n",
 499                prom_early_allocated);
 500 }