Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 1 | /* |
| 2 | * libfdt - Flat Device Tree manipulation |
| 3 | * Copyright (C) 2006 David Gibson, IBM Corporation. |
| 4 | * |
| 5 | * This library is free software; you can redistribute it and/or |
| 6 | * modify it under the terms of the GNU Lesser General Public License |
| 7 | * as published by the Free Software Foundation; either version 2.1 of |
| 8 | * the License, or (at your option) any later version. |
| 9 | * |
| 10 | * This library is distributed in the hope that it will be useful, but |
| 11 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | * Lesser General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU Lesser General Public |
| 16 | * License along with this library; if not, write to the Free Software |
| 17 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 18 | */ |
Gerald Van Baren | 8096b3b | 2007-04-20 22:46:53 -0400 | [diff] [blame] | 19 | #include "config.h" |
| 20 | #if CONFIG_OF_LIBFDT |
| 21 | |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 22 | #include "libfdt_env.h" |
| 23 | |
| 24 | #include <fdt.h> |
| 25 | #include <libfdt.h> |
| 26 | |
| 27 | #include "libfdt_internal.h" |
| 28 | |
Wolfgang Denk | 94abd7c | 2007-04-04 01:49:15 +0200 | [diff] [blame] | 29 | #define CHECK_HEADER(fdt) { \ |
| 30 | int err; \ |
Gerald Van Baren | 6679f92 | 2007-04-06 14:17:14 -0400 | [diff] [blame] | 31 | if ((err = fdt_check_header(fdt)) != 0) \ |
Wolfgang Denk | 94abd7c | 2007-04-04 01:49:15 +0200 | [diff] [blame] | 32 | return err; \ |
| 33 | } |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 34 | |
| 35 | static int offset_streq(const void *fdt, int offset, |
| 36 | const char *s, int len) |
| 37 | { |
| 38 | const char *p = fdt_offset_ptr(fdt, offset, len+1); |
| 39 | |
| 40 | if (! p) |
| 41 | /* short match */ |
| 42 | return 0; |
| 43 | |
| 44 | if (memcmp(p, s, len) != 0) |
| 45 | return 0; |
| 46 | |
| 47 | if (p[len] != '\0') |
| 48 | return 0; |
| 49 | |
| 50 | return 1; |
| 51 | } |
| 52 | |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 53 | /* |
| 54 | * Return a pointer to the string at the given string offset. |
| 55 | */ |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 56 | char *fdt_string(const void *fdt, int stroffset) |
| 57 | { |
| 58 | return (char *)fdt + fdt_off_dt_strings(fdt) + stroffset; |
| 59 | } |
| 60 | |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 61 | /* |
| 62 | * Return the node offset of the node specified by: |
| 63 | * parentoffset - starting place (0 to start at the root) |
| 64 | * name - name being searched for |
| 65 | * namelen - length of the name: typically strlen(name) |
| 66 | * |
| 67 | * Notes: |
| 68 | * If the start node has subnodes, the subnodes are _not_ searched for the |
| 69 | * requested name. |
| 70 | */ |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 71 | int fdt_subnode_offset_namelen(const void *fdt, int parentoffset, |
| 72 | const char *name, int namelen) |
| 73 | { |
| 74 | int level = 0; |
| 75 | uint32_t tag; |
| 76 | int offset, nextoffset; |
| 77 | |
| 78 | CHECK_HEADER(fdt); |
| 79 | |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 80 | tag = fdt_next_tag(fdt, parentoffset, &nextoffset, NULL); |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 81 | if (tag != FDT_BEGIN_NODE) |
| 82 | return -FDT_ERR_BADOFFSET; |
| 83 | |
| 84 | do { |
| 85 | offset = nextoffset; |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 86 | tag = fdt_next_tag(fdt, offset, &nextoffset, NULL); |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 87 | |
| 88 | switch (tag) { |
| 89 | case FDT_END: |
| 90 | return -FDT_ERR_TRUNCATED; |
| 91 | |
| 92 | case FDT_BEGIN_NODE: |
| 93 | level++; |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 94 | /* |
| 95 | * If we are nested down levels, ignore the strings |
| 96 | * until we get back to the proper level. |
| 97 | */ |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 98 | if (level != 1) |
| 99 | continue; |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 100 | |
| 101 | /* Return the offset if this is "our" string. */ |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 102 | if (offset_streq(fdt, offset+FDT_TAGSIZE, name, namelen)) |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 103 | return offset; |
| 104 | break; |
| 105 | |
| 106 | case FDT_END_NODE: |
| 107 | level--; |
| 108 | break; |
| 109 | |
| 110 | case FDT_PROP: |
| 111 | case FDT_NOP: |
| 112 | break; |
| 113 | |
| 114 | default: |
| 115 | return -FDT_ERR_BADSTRUCTURE; |
| 116 | } |
| 117 | } while (level >= 0); |
| 118 | |
| 119 | return -FDT_ERR_NOTFOUND; |
| 120 | } |
| 121 | |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 122 | /* |
| 123 | * See fdt_subnode_offset_namelen() |
| 124 | */ |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 125 | int fdt_subnode_offset(const void *fdt, int parentoffset, |
| 126 | const char *name) |
| 127 | { |
| 128 | return fdt_subnode_offset_namelen(fdt, parentoffset, name, strlen(name)); |
| 129 | } |
| 130 | |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 131 | /* |
| 132 | * Searches for the node corresponding to the given path and returns the |
| 133 | * offset of that node. |
| 134 | */ |
Gerald Van Baren | 1a86116 | 2007-06-06 22:47:58 -0400 | [diff] [blame^] | 135 | int fdt_find_node_by_path(const void *fdt, const char *path) |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 136 | { |
| 137 | const char *end = path + strlen(path); |
| 138 | const char *p = path; |
| 139 | int offset = 0; |
| 140 | |
| 141 | CHECK_HEADER(fdt); |
| 142 | |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 143 | /* Paths must be absolute */ |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 144 | if (*path != '/') |
| 145 | return -FDT_ERR_BADPATH; |
| 146 | |
| 147 | while (*p) { |
| 148 | const char *q; |
| 149 | |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 150 | /* Skip path separator(s) */ |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 151 | while (*p == '/') |
| 152 | p++; |
| 153 | if (! *p) |
| 154 | return -FDT_ERR_BADPATH; |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 155 | |
| 156 | /* |
| 157 | * Find the next path separator. The characters between |
| 158 | * p and q are the next segment of the the path to find. |
| 159 | */ |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 160 | q = strchr(p, '/'); |
| 161 | if (! q) |
| 162 | q = end; |
| 163 | |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 164 | /* |
| 165 | * Find the offset corresponding to the this path segment. |
| 166 | */ |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 167 | offset = fdt_subnode_offset_namelen(fdt, offset, p, q-p); |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 168 | |
| 169 | /* Oops, error, abort abort abort */ |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 170 | if (offset < 0) |
| 171 | return offset; |
| 172 | |
| 173 | p = q; |
| 174 | } |
| 175 | |
Gerald Van Baren | aea03c4 | 2007-03-31 14:30:53 -0400 | [diff] [blame] | 176 | return offset; |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 177 | } |
| 178 | |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 179 | /* |
| 180 | * Given the offset of a node and a name of a property in that node, return |
| 181 | * a pointer to the property struct. |
| 182 | */ |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 183 | struct fdt_property *fdt_get_property(const void *fdt, |
| 184 | int nodeoffset, |
| 185 | const char *name, int *lenp) |
| 186 | { |
| 187 | int level = 0; |
| 188 | uint32_t tag; |
| 189 | struct fdt_property *prop; |
| 190 | int namestroff; |
| 191 | int offset, nextoffset; |
| 192 | int err; |
| 193 | |
Gerald Van Baren | 6679f92 | 2007-04-06 14:17:14 -0400 | [diff] [blame] | 194 | if ((err = fdt_check_header(fdt)) != 0) |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 195 | goto fail; |
| 196 | |
| 197 | err = -FDT_ERR_BADOFFSET; |
| 198 | if (nodeoffset % FDT_TAGSIZE) |
| 199 | goto fail; |
| 200 | |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 201 | tag = fdt_next_tag(fdt, nodeoffset, &nextoffset, NULL); |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 202 | if (tag != FDT_BEGIN_NODE) |
| 203 | goto fail; |
| 204 | |
| 205 | do { |
| 206 | offset = nextoffset; |
| 207 | |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 208 | tag = fdt_next_tag(fdt, offset, &nextoffset, NULL); |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 209 | switch (tag) { |
| 210 | case FDT_END: |
| 211 | err = -FDT_ERR_TRUNCATED; |
| 212 | goto fail; |
| 213 | |
| 214 | case FDT_BEGIN_NODE: |
| 215 | level++; |
| 216 | break; |
| 217 | |
| 218 | case FDT_END_NODE: |
| 219 | level--; |
| 220 | break; |
| 221 | |
| 222 | case FDT_PROP: |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 223 | /* |
| 224 | * If we are nested down levels, ignore the strings |
| 225 | * until we get back to the proper level. |
| 226 | */ |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 227 | if (level != 0) |
| 228 | continue; |
| 229 | |
| 230 | err = -FDT_ERR_BADSTRUCTURE; |
| 231 | prop = fdt_offset_ptr_typed(fdt, offset, prop); |
| 232 | if (! prop) |
| 233 | goto fail; |
| 234 | namestroff = fdt32_to_cpu(prop->nameoff); |
| 235 | if (streq(fdt_string(fdt, namestroff), name)) { |
| 236 | /* Found it! */ |
| 237 | int len = fdt32_to_cpu(prop->len); |
| 238 | prop = fdt_offset_ptr(fdt, offset, |
| 239 | sizeof(*prop)+len); |
| 240 | if (! prop) |
| 241 | goto fail; |
| 242 | |
| 243 | if (lenp) |
| 244 | *lenp = len; |
Gerald Van Baren | aea03c4 | 2007-03-31 14:30:53 -0400 | [diff] [blame] | 245 | |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 246 | return prop; |
| 247 | } |
| 248 | break; |
| 249 | |
| 250 | case FDT_NOP: |
| 251 | break; |
| 252 | |
| 253 | default: |
| 254 | err = -FDT_ERR_BADSTRUCTURE; |
| 255 | goto fail; |
| 256 | } |
| 257 | } while (level >= 0); |
| 258 | |
| 259 | err = -FDT_ERR_NOTFOUND; |
Wolfgang Denk | 94abd7c | 2007-04-04 01:49:15 +0200 | [diff] [blame] | 260 | fail: |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 261 | if (lenp) |
| 262 | *lenp = err; |
| 263 | return NULL; |
| 264 | } |
| 265 | |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 266 | /* |
| 267 | * Given the offset of a node and a name of a property in that node, return |
| 268 | * a pointer to the property data (ONLY). |
| 269 | */ |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 270 | void *fdt_getprop(const void *fdt, int nodeoffset, |
| 271 | const char *name, int *lenp) |
| 272 | { |
| 273 | const struct fdt_property *prop; |
| 274 | |
| 275 | prop = fdt_get_property(fdt, nodeoffset, name, lenp); |
| 276 | if (! prop) |
| 277 | return NULL; |
| 278 | |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 279 | return (void *)prop->data; |
Gerald Van Baren | 3574817 | 2007-03-31 12:00:56 -0400 | [diff] [blame] | 280 | } |
Gerald Van Baren | 3af0d58 | 2007-03-31 12:13:43 -0400 | [diff] [blame] | 281 | |
| 282 | |
| 283 | uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset, char **namep) |
| 284 | { |
| 285 | const uint32_t *tagp, *lenp; |
| 286 | uint32_t tag; |
| 287 | const char *p; |
| 288 | |
| 289 | if (offset % FDT_TAGSIZE) |
| 290 | return -1; |
| 291 | |
| 292 | tagp = fdt_offset_ptr(fdt, offset, FDT_TAGSIZE); |
| 293 | if (! tagp) |
| 294 | return FDT_END; /* premature end */ |
| 295 | tag = fdt32_to_cpu(*tagp); |
| 296 | offset += FDT_TAGSIZE; |
| 297 | |
| 298 | switch (tag) { |
| 299 | case FDT_BEGIN_NODE: |
| 300 | if(namep) |
| 301 | *namep = fdt_offset_ptr(fdt, offset, 1); |
| 302 | |
| 303 | /* skip name */ |
| 304 | do { |
| 305 | p = fdt_offset_ptr(fdt, offset++, 1); |
| 306 | } while (p && (*p != '\0')); |
| 307 | if (! p) |
| 308 | return FDT_END; |
| 309 | break; |
| 310 | case FDT_PROP: |
| 311 | lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp)); |
| 312 | if (! lenp) |
| 313 | return FDT_END; |
| 314 | /* |
| 315 | * Get the property and set the namep to the name. |
| 316 | */ |
| 317 | if(namep) { |
| 318 | struct fdt_property *prop; |
| 319 | |
| 320 | prop = fdt_offset_ptr_typed(fdt, offset - FDT_TAGSIZE, prop); |
| 321 | if (! prop) |
| 322 | return -FDT_ERR_BADSTRUCTURE; |
| 323 | *namep = fdt_string(fdt, fdt32_to_cpu(prop->nameoff)); |
| 324 | } |
| 325 | /* skip name offset, length and value */ |
| 326 | offset += 2*FDT_TAGSIZE + fdt32_to_cpu(*lenp); |
| 327 | break; |
| 328 | } |
| 329 | |
| 330 | if (nextoffset) |
| 331 | *nextoffset = ALIGN(offset, FDT_TAGSIZE); |
| 332 | |
| 333 | return tag; |
| 334 | } |
Gerald Van Baren | 3f9f08c | 2007-04-14 22:46:41 -0400 | [diff] [blame] | 335 | |
| 336 | /* |
| 337 | * Return the number of used reserve map entries and total slots available. |
| 338 | */ |
| 339 | int fdt_num_reservemap(void *fdt, int *used, int *total) |
| 340 | { |
| 341 | struct fdt_reserve_entry *re; |
| 342 | int start; |
| 343 | int end; |
| 344 | int err = fdt_check_header(fdt); |
| 345 | |
| 346 | if (err != 0) |
| 347 | return err; |
| 348 | |
| 349 | start = fdt_off_mem_rsvmap(fdt); |
| 350 | |
| 351 | /* |
| 352 | * Convention is that the reserve map is before the dt_struct, |
| 353 | * but it does not have to be. |
| 354 | */ |
| 355 | end = fdt_totalsize(fdt); |
| 356 | if (end > fdt_off_dt_struct(fdt)) |
| 357 | end = fdt_off_dt_struct(fdt); |
| 358 | if (end > fdt_off_dt_strings(fdt)) |
| 359 | end = fdt_off_dt_strings(fdt); |
| 360 | |
| 361 | /* |
| 362 | * Since the reserved area list is zero terminated, you get one fewer. |
| 363 | */ |
| 364 | if (total) |
| 365 | *total = ((end - start) / sizeof(struct fdt_reserve_entry)) - 1; |
| 366 | |
| 367 | if (used) { |
| 368 | *used = 0; |
| 369 | while (start < end) { |
| 370 | re = (struct fdt_reserve_entry *)(fdt + start); |
| 371 | if (re->size == 0) |
| 372 | return 0; /* zero size terminates the list */ |
| 373 | |
| 374 | *used += 1; |
| 375 | start += sizeof(struct fdt_reserve_entry); |
| 376 | } |
| 377 | /* |
| 378 | * If we get here, there was no zero size termination. |
| 379 | */ |
| 380 | return -FDT_ERR_BADLAYOUT; |
| 381 | } |
| 382 | return 0; |
| 383 | } |
| 384 | |
| 385 | /* |
| 386 | * Return the nth reserve map entry. |
| 387 | */ |
| 388 | int fdt_get_reservemap(void *fdt, int n, struct fdt_reserve_entry *re) |
| 389 | { |
| 390 | int used; |
| 391 | int total; |
| 392 | int err; |
| 393 | |
| 394 | err = fdt_num_reservemap(fdt, &used, &total); |
| 395 | if (err != 0) |
| 396 | return err; |
| 397 | |
| 398 | if (n >= total) |
| 399 | return -FDT_ERR_NOSPACE; |
| 400 | if (re) { |
| 401 | *re = *(struct fdt_reserve_entry *) |
| 402 | _fdt_offset_ptr(fdt, n * sizeof(struct fdt_reserve_entry)); |
| 403 | } |
| 404 | return 0; |
| 405 | } |
Gerald Van Baren | 8096b3b | 2007-04-20 22:46:53 -0400 | [diff] [blame] | 406 | |
| 407 | #endif /* CONFIG_OF_LIBFDT */ |
| 408 | |