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