1 #ifndef _LIBFDT_H 2 #define _LIBFDT_H 3 /* 4 * libfdt - Flat Device Tree manipulation 5 * Copyright (C) 2006 David Gibson, IBM Corporation. 6 * 7 * libfdt is dual licensed: you can use it either under the terms of 8 * the GPL, or the BSD license, at your option. 9 * 10 * a) This library is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public License as 12 * published by the Free Software Foundation; either version 2 of the 13 * License, or (at your option) any later version. 14 * 15 * This library is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public 21 * License along with this library; if not, write to the Free 22 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, 23 * MA 02110-1301 USA 24 * 25 * Alternatively, 26 * 27 * b) Redistribution and use in source and binary forms, with or 28 * without modification, are permitted provided that the following 29 * conditions are met: 30 * 31 * 1. Redistributions of source code must retain the above 32 * copyright notice, this list of conditions and the following 33 * disclaimer. 34 * 2. Redistributions in binary form must reproduce the above 35 * copyright notice, this list of conditions and the following 36 * disclaimer in the documentation and/or other materials 37 * provided with the distribution. 38 * 39 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 40 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 41 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 42 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 43 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 44 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 49 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 50 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 51 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 52 */ 53 54 #include "libfdt_env.h" 55 #include "fdt.h" 56 57 #define FDT_FIRST_SUPPORTED_VERSION 0x10 58 #define FDT_LAST_SUPPORTED_VERSION 0x11 59 60 /* Error codes: informative error codes */ 61 #define FDT_ERR_NOTFOUND 1 62 /* FDT_ERR_NOTFOUND: The requested node or property does not exist */ 63 #define FDT_ERR_EXISTS 2 64 /* FDT_ERR_EXISTS: Attempted to create a node or property which 65 * already exists */ 66 #define FDT_ERR_NOSPACE 3 67 /* FDT_ERR_NOSPACE: Operation needed to expand the device 68 * tree, but its buffer did not have sufficient space to 69 * contain the expanded tree. Use fdt_open_into() to move the 70 * device tree to a buffer with more space. */ 71 72 /* Error codes: codes for bad parameters */ 73 #define FDT_ERR_BADOFFSET 4 74 /* FDT_ERR_BADOFFSET: Function was passed a structure block 75 * offset which is out-of-bounds, or which points to an 76 * unsuitable part of the structure for the operation. */ 77 #define FDT_ERR_BADPATH 5 78 /* FDT_ERR_BADPATH: Function was passed a badly formatted path 79 * (e.g. missing a leading / for a function which requires an 80 * absolute path) */ 81 #define FDT_ERR_BADPHANDLE 6 82 /* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle. 83 * This can be caused either by an invalid phandle property 84 * length, or the phandle value was either 0 or -1, which are 85 * not permitted. */ 86 #define FDT_ERR_BADSTATE 7 87 /* FDT_ERR_BADSTATE: Function was passed an incomplete device 88 * tree created by the sequential-write functions, which is 89 * not sufficiently complete for the requested operation. */ 90 91 /* Error codes: codes for bad device tree blobs */ 92 #define FDT_ERR_TRUNCATED 8 93 /* FDT_ERR_TRUNCATED: Structure block of the given device tree 94 * ends without an FDT_END tag. */ 95 #define FDT_ERR_BADMAGIC 9 96 /* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a 97 * device tree at all - it is missing the flattened device 98 * tree magic number. */ 99 #define FDT_ERR_BADVERSION 10 100 /* FDT_ERR_BADVERSION: Given device tree has a version which 101 * can't be handled by the requested operation. For 102 * read-write functions, this may mean that fdt_open_into() is 103 * required to convert the tree to the expected version. */ 104 #define FDT_ERR_BADSTRUCTURE 11 105 /* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt 106 * structure block or other serious error (e.g. misnested 107 * nodes, or subnodes preceding properties). */ 108 #define FDT_ERR_BADLAYOUT 12 109 /* FDT_ERR_BADLAYOUT: For read-write functions, the given 110 * device tree has it's sub-blocks in an order that the 111 * function can't handle (memory reserve map, then structure, 112 * then strings). Use fdt_open_into() to reorganize the tree 113 * into a form suitable for the read-write operations. */ 114 115 /* "Can't happen" error indicating a bug in libfdt */ 116 #define FDT_ERR_INTERNAL 13 117 /* FDT_ERR_INTERNAL: libfdt has failed an internal assertion. 118 * Should never be returned, if it is, it indicates a bug in 119 * libfdt itself. */ 120 121 /* Errors in device tree content */ 122 #define FDT_ERR_BADNCELLS 14 123 /* FDT_ERR_BADNCELLS: Device tree has a #address-cells, #size-cells 124 * or similar property with a bad format or value */ 125 126 #define FDT_ERR_BADVALUE 15 127 /* FDT_ERR_BADVALUE: Device tree has a property with an unexpected 128 * value. For example: a property expected to contain a string list 129 * is not NUL-terminated within the length of its value. */ 130 131 #define FDT_ERR_BADOVERLAY 16 132 /* FDT_ERR_BADOVERLAY: The device tree overlay, while 133 * correctly structured, cannot be applied due to some 134 * unexpected or missing value, property or node. */ 135 136 #define FDT_ERR_NOPHANDLES 17 137 /* FDT_ERR_NOPHANDLES: The device tree doesn't have any 138 * phandle available anymore without causing an overflow */ 139 140 #define FDT_ERR_MAX 17 141 142 /**********************************************************************/ 143 /* Low-level functions (you probably don't need these) */ 144 /**********************************************************************/ 145 146 const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen); 147 static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen) 148 { 149 return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen); 150 } 151 152 uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset); 153 154 /**********************************************************************/ 155 /* Traversal functions */ 156 /**********************************************************************/ 157 158 int fdt_next_node(const void *fdt, int offset, int *depth); 159 160 /** 161 * fdt_first_subnode() - get offset of first direct subnode 162 * 163 * @fdt: FDT blob 164 * @offset: Offset of node to check 165 * @return offset of first subnode, or -FDT_ERR_NOTFOUND if there is none 166 */ 167 int fdt_first_subnode(const void *fdt, int offset); 168 169 /** 170 * fdt_next_subnode() - get offset of next direct subnode 171 * 172 * After first calling fdt_first_subnode(), call this function repeatedly to 173 * get direct subnodes of a parent node. 174 * 175 * @fdt: FDT blob 176 * @offset: Offset of previous subnode 177 * @return offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more 178 * subnodes 179 */ 180 int fdt_next_subnode(const void *fdt, int offset); 181 182 /** 183 * fdt_for_each_subnode - iterate over all subnodes of a parent 184 * 185 * @node: child node (int, lvalue) 186 * @fdt: FDT blob (const void *) 187 * @parent: parent node (int) 188 * 189 * This is actually a wrapper around a for loop and would be used like so: 190 * 191 * fdt_for_each_subnode(node, fdt, parent) { 192 * Use node 193 * ... 194 * } 195 * 196 * if ((node < 0) && (node != -FDT_ERR_NOT_FOUND)) { 197 * Error handling 198 * } 199 * 200 * Note that this is implemented as a macro and @node is used as 201 * iterator in the loop. The parent variable be constant or even a 202 * literal. 203 * 204 */ 205 #define fdt_for_each_subnode(node, fdt, parent) \ 206 for (node = fdt_first_subnode(fdt, parent); \ 207 node >= 0; \ 208 node = fdt_next_subnode(fdt, node)) 209 210 /**********************************************************************/ 211 /* General functions */ 212 /**********************************************************************/ 213 214 #define fdt_get_header(fdt, field) \ 215 (fdt32_to_cpu(((const struct fdt_header *)(fdt))->field)) 216 #define fdt_magic(fdt) (fdt_get_header(fdt, magic)) 217 #define fdt_totalsize(fdt) (fdt_get_header(fdt, totalsize)) 218 #define fdt_off_dt_struct(fdt) (fdt_get_header(fdt, off_dt_struct)) 219 #define fdt_off_dt_strings(fdt) (fdt_get_header(fdt, off_dt_strings)) 220 #define fdt_off_mem_rsvmap(fdt) (fdt_get_header(fdt, off_mem_rsvmap)) 221 #define fdt_version(fdt) (fdt_get_header(fdt, version)) 222 #define fdt_last_comp_version(fdt) (fdt_get_header(fdt, last_comp_version)) 223 #define fdt_boot_cpuid_phys(fdt) (fdt_get_header(fdt, boot_cpuid_phys)) 224 #define fdt_size_dt_strings(fdt) (fdt_get_header(fdt, size_dt_strings)) 225 #define fdt_size_dt_struct(fdt) (fdt_get_header(fdt, size_dt_struct)) 226 227 #define __fdt_set_hdr(name) \ 228 static inline void fdt_set_##name(void *fdt, uint32_t val) \ 229 { \ 230 struct fdt_header *fdth = (struct fdt_header *)fdt; \ 231 fdth->name = cpu_to_fdt32(val); \ 232 } 233 __fdt_set_hdr(magic); 234 __fdt_set_hdr(totalsize); 235 __fdt_set_hdr(off_dt_struct); 236 __fdt_set_hdr(off_dt_strings); 237 __fdt_set_hdr(off_mem_rsvmap); 238 __fdt_set_hdr(version); 239 __fdt_set_hdr(last_comp_version); 240 __fdt_set_hdr(boot_cpuid_phys); 241 __fdt_set_hdr(size_dt_strings); 242 __fdt_set_hdr(size_dt_struct); 243 #undef __fdt_set_hdr 244 245 /** 246 * fdt_check_header - sanity check a device tree or possible device tree 247 * @fdt: pointer to data which might be a flattened device tree 248 * 249 * fdt_check_header() checks that the given buffer contains what 250 * appears to be a flattened device tree with sane information in its 251 * header. 252 * 253 * returns: 254 * 0, if the buffer appears to contain a valid device tree 255 * -FDT_ERR_BADMAGIC, 256 * -FDT_ERR_BADVERSION, 257 * -FDT_ERR_BADSTATE, standard meanings, as above 258 */ 259 int fdt_check_header(const void *fdt); 260 261 /** 262 * fdt_move - move a device tree around in memory 263 * @fdt: pointer to the device tree to move 264 * @buf: pointer to memory where the device is to be moved 265 * @bufsize: size of the memory space at buf 266 * 267 * fdt_move() relocates, if possible, the device tree blob located at 268 * fdt to the buffer at buf of size bufsize. The buffer may overlap 269 * with the existing device tree blob at fdt. Therefore, 270 * fdt_move(fdt, fdt, fdt_totalsize(fdt)) 271 * should always succeed. 272 * 273 * returns: 274 * 0, on success 275 * -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree 276 * -FDT_ERR_BADMAGIC, 277 * -FDT_ERR_BADVERSION, 278 * -FDT_ERR_BADSTATE, standard meanings 279 */ 280 int fdt_move(const void *fdt, void *buf, int bufsize); 281 282 /**********************************************************************/ 283 /* Read-only functions */ 284 /**********************************************************************/ 285 286 /** 287 * fdt_string - retrieve a string from the strings block of a device tree 288 * @fdt: pointer to the device tree blob 289 * @stroffset: offset of the string within the strings block (native endian) 290 * 291 * fdt_string() retrieves a pointer to a single string from the 292 * strings block of the device tree blob at fdt. 293 * 294 * returns: 295 * a pointer to the string, on success 296 * NULL, if stroffset is out of bounds 297 */ 298 const char *fdt_string(const void *fdt, int stroffset); 299 300 /** 301 * fdt_get_max_phandle - retrieves the highest phandle in a tree 302 * @fdt: pointer to the device tree blob 303 * 304 * fdt_get_max_phandle retrieves the highest phandle in the given 305 * device tree. This will ignore badly formatted phandles, or phandles 306 * with a value of 0 or -1. 307 * 308 * returns: 309 * the highest phandle on success 310 * 0, if no phandle was found in the device tree 311 * -1, if an error occurred 312 */ 313 uint32_t fdt_get_max_phandle(const void *fdt); 314 315 /** 316 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries 317 * @fdt: pointer to the device tree blob 318 * 319 * Returns the number of entries in the device tree blob's memory 320 * reservation map. This does not include the terminating 0,0 entry 321 * or any other (0,0) entries reserved for expansion. 322 * 323 * returns: 324 * the number of entries 325 */ 326 int fdt_num_mem_rsv(const void *fdt); 327 328 /** 329 * fdt_get_mem_rsv - retrieve one memory reserve map entry 330 * @fdt: pointer to the device tree blob 331 * @address, @size: pointers to 64-bit variables 332 * 333 * On success, *address and *size will contain the address and size of 334 * the n-th reserve map entry from the device tree blob, in 335 * native-endian format. 336 * 337 * returns: 338 * 0, on success 339 * -FDT_ERR_BADMAGIC, 340 * -FDT_ERR_BADVERSION, 341 * -FDT_ERR_BADSTATE, standard meanings 342 */ 343 int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size); 344 345 /** 346 * fdt_subnode_offset_namelen - find a subnode based on substring 347 * @fdt: pointer to the device tree blob 348 * @parentoffset: structure block offset of a node 349 * @name: name of the subnode to locate 350 * @namelen: number of characters of name to consider 351 * 352 * Identical to fdt_subnode_offset(), but only examine the first 353 * namelen characters of name for matching the subnode name. This is 354 * useful for finding subnodes based on a portion of a larger string, 355 * such as a full path. 356 */ 357 int fdt_subnode_offset_namelen(const void *fdt, int parentoffset, 358 const char *name, int namelen); 359 /** 360 * fdt_subnode_offset - find a subnode of a given node 361 * @fdt: pointer to the device tree blob 362 * @parentoffset: structure block offset of a node 363 * @name: name of the subnode to locate 364 * 365 * fdt_subnode_offset() finds a subnode of the node at structure block 366 * offset parentoffset with the given name. name may include a unit 367 * address, in which case fdt_subnode_offset() will find the subnode 368 * with that unit address, or the unit address may be omitted, in 369 * which case fdt_subnode_offset() will find an arbitrary subnode 370 * whose name excluding unit address matches the given name. 371 * 372 * returns: 373 * structure block offset of the requested subnode (>=0), on success 374 * -FDT_ERR_NOTFOUND, if the requested subnode does not exist 375 * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE 376 * tag 377 * -FDT_ERR_BADMAGIC, 378 * -FDT_ERR_BADVERSION, 379 * -FDT_ERR_BADSTATE, 380 * -FDT_ERR_BADSTRUCTURE, 381 * -FDT_ERR_TRUNCATED, standard meanings. 382 */ 383 int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name); 384 385 /** 386 * fdt_path_offset_namelen - find a tree node by its full path 387 * @fdt: pointer to the device tree blob 388 * @path: full path of the node to locate 389 * @namelen: number of characters of path to consider 390 * 391 * Identical to fdt_path_offset(), but only consider the first namelen 392 * characters of path as the path name. 393 */ 394 int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen); 395 396 /** 397 * fdt_path_offset - find a tree node by its full path 398 * @fdt: pointer to the device tree blob 399 * @path: full path of the node to locate 400 * 401 * fdt_path_offset() finds a node of a given path in the device tree. 402 * Each path component may omit the unit address portion, but the 403 * results of this are undefined if any such path component is 404 * ambiguous (that is if there are multiple nodes at the relevant 405 * level matching the given component, differentiated only by unit 406 * address). 407 * 408 * returns: 409 * structure block offset of the node with the requested path (>=0), on 410 * success 411 * -FDT_ERR_BADPATH, given path does not begin with '/' or is invalid 412 * -FDT_ERR_NOTFOUND, if the requested node does not exist 413 * -FDT_ERR_BADMAGIC, 414 * -FDT_ERR_BADVERSION, 415 * -FDT_ERR_BADSTATE, 416 * -FDT_ERR_BADSTRUCTURE, 417 * -FDT_ERR_TRUNCATED, standard meanings. 418 */ 419 int fdt_path_offset(const void *fdt, const char *path); 420 421 /** 422 * fdt_get_name - retrieve the name of a given node 423 * @fdt: pointer to the device tree blob 424 * @nodeoffset: structure block offset of the starting node 425 * @lenp: pointer to an integer variable (will be overwritten) or NULL 426 * 427 * fdt_get_name() retrieves the name (including unit address) of the 428 * device tree node at structure block offset nodeoffset. If lenp is 429 * non-NULL, the length of this name is also returned, in the integer 430 * pointed to by lenp. 431 * 432 * returns: 433 * pointer to the node's name, on success 434 * If lenp is non-NULL, *lenp contains the length of that name 435 * (>=0) 436 * NULL, on error 437 * if lenp is non-NULL *lenp contains an error code (<0): 438 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE 439 * tag 440 * -FDT_ERR_BADMAGIC, 441 * -FDT_ERR_BADVERSION, 442 * -FDT_ERR_BADSTATE, standard meanings 443 */ 444 const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp); 445 446 /** 447 * fdt_first_property_offset - find the offset of a node's first property 448 * @fdt: pointer to the device tree blob 449 * @nodeoffset: structure block offset of a node 450 * 451 * fdt_first_property_offset() finds the first property of the node at 452 * the given structure block offset. 453 * 454 * returns: 455 * structure block offset of the property (>=0), on success 456 * -FDT_ERR_NOTFOUND, if the requested node has no properties 457 * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag 458 * -FDT_ERR_BADMAGIC, 459 * -FDT_ERR_BADVERSION, 460 * -FDT_ERR_BADSTATE, 461 * -FDT_ERR_BADSTRUCTURE, 462 * -FDT_ERR_TRUNCATED, standard meanings. 463 */ 464 int fdt_first_property_offset(const void *fdt, int nodeoffset); 465 466 /** 467 * fdt_next_property_offset - step through a node's properties 468 * @fdt: pointer to the device tree blob 469 * @offset: structure block offset of a property 470 * 471 * fdt_next_property_offset() finds the property immediately after the 472 * one at the given structure block offset. This will be a property 473 * of the same node as the given property. 474 * 475 * returns: 476 * structure block offset of the next property (>=0), on success 477 * -FDT_ERR_NOTFOUND, if the given property is the last in its node 478 * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag 479 * -FDT_ERR_BADMAGIC, 480 * -FDT_ERR_BADVERSION, 481 * -FDT_ERR_BADSTATE, 482 * -FDT_ERR_BADSTRUCTURE, 483 * -FDT_ERR_TRUNCATED, standard meanings. 484 */ 485 int fdt_next_property_offset(const void *fdt, int offset); 486 487 /** 488 * fdt_for_each_property_offset - iterate over all properties of a node 489 * 490 * @property_offset: property offset (int, lvalue) 491 * @fdt: FDT blob (const void *) 492 * @node: node offset (int) 493 * 494 * This is actually a wrapper around a for loop and would be used like so: 495 * 496 * fdt_for_each_property_offset(property, fdt, node) { 497 * Use property 498 * ... 499 * } 500 * 501 * if ((property < 0) && (property != -FDT_ERR_NOT_FOUND)) { 502 * Error handling 503 * } 504 * 505 * Note that this is implemented as a macro and property is used as 506 * iterator in the loop. The node variable can be constant or even a 507 * literal. 508 */ 509 #define fdt_for_each_property_offset(property, fdt, node) \ 510 for (property = fdt_first_property_offset(fdt, node); \ 511 property >= 0; \ 512 property = fdt_next_property_offset(fdt, property)) 513 514 /** 515 * fdt_get_property_by_offset - retrieve the property at a given offset 516 * @fdt: pointer to the device tree blob 517 * @offset: offset of the property to retrieve 518 * @lenp: pointer to an integer variable (will be overwritten) or NULL 519 * 520 * fdt_get_property_by_offset() retrieves a pointer to the 521 * fdt_property structure within the device tree blob at the given 522 * offset. If lenp is non-NULL, the length of the property value is 523 * also returned, in the integer pointed to by lenp. 524 * 525 * returns: 526 * pointer to the structure representing the property 527 * if lenp is non-NULL, *lenp contains the length of the property 528 * value (>=0) 529 * NULL, on error 530 * if lenp is non-NULL, *lenp contains an error code (<0): 531 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag 532 * -FDT_ERR_BADMAGIC, 533 * -FDT_ERR_BADVERSION, 534 * -FDT_ERR_BADSTATE, 535 * -FDT_ERR_BADSTRUCTURE, 536 * -FDT_ERR_TRUNCATED, standard meanings 537 */ 538 const struct fdt_property *fdt_get_property_by_offset(const void *fdt, 539 int offset, 540 int *lenp); 541 542 /** 543 * fdt_get_property_namelen - find a property based on substring 544 * @fdt: pointer to the device tree blob 545 * @nodeoffset: offset of the node whose property to find 546 * @name: name of the property to find 547 * @namelen: number of characters of name to consider 548 * @lenp: pointer to an integer variable (will be overwritten) or NULL 549 * 550 * Identical to fdt_get_property(), but only examine the first namelen 551 * characters of name for matching the property name. 552 */ 553 const struct fdt_property *fdt_get_property_namelen(const void *fdt, 554 int nodeoffset, 555 const char *name, 556 int namelen, int *lenp); 557 558 /** 559 * fdt_get_property - find a given property in a given node 560 * @fdt: pointer to the device tree blob 561 * @nodeoffset: offset of the node whose property to find 562 * @name: name of the property to find 563 * @lenp: pointer to an integer variable (will be overwritten) or NULL 564 * 565 * fdt_get_property() retrieves a pointer to the fdt_property 566 * structure within the device tree blob corresponding to the property 567 * named 'name' of the node at offset nodeoffset. If lenp is 568 * non-NULL, the length of the property value is also returned, in the 569 * integer pointed to by lenp. 570 * 571 * returns: 572 * pointer to the structure representing the property 573 * if lenp is non-NULL, *lenp contains the length of the property 574 * value (>=0) 575 * NULL, on error 576 * if lenp is non-NULL, *lenp contains an error code (<0): 577 * -FDT_ERR_NOTFOUND, node does not have named property 578 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE 579 * tag 580 * -FDT_ERR_BADMAGIC, 581 * -FDT_ERR_BADVERSION, 582 * -FDT_ERR_BADSTATE, 583 * -FDT_ERR_BADSTRUCTURE, 584 * -FDT_ERR_TRUNCATED, standard meanings 585 */ 586 const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset, 587 const char *name, int *lenp); 588 static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset, 589 const char *name, 590 int *lenp) 591 { 592 return (struct fdt_property *)(uintptr_t) 593 fdt_get_property(fdt, nodeoffset, name, lenp); 594 } 595 596 /** 597 * fdt_getprop_by_offset - retrieve the value of a property at a given offset 598 * @fdt: pointer to the device tree blob 599 * @ffset: offset of the property to read 600 * @namep: pointer to a string variable (will be overwritten) or NULL 601 * @lenp: pointer to an integer variable (will be overwritten) or NULL 602 * 603 * fdt_getprop_by_offset() retrieves a pointer to the value of the 604 * property at structure block offset 'offset' (this will be a pointer 605 * to within the device blob itself, not a copy of the value). If 606 * lenp is non-NULL, the length of the property value is also 607 * returned, in the integer pointed to by lenp. If namep is non-NULL, 608 * the property's namne will also be returned in the char * pointed to 609 * by namep (this will be a pointer to within the device tree's string 610 * block, not a new copy of the name). 611 * 612 * returns: 613 * pointer to the property's value 614 * if lenp is non-NULL, *lenp contains the length of the property 615 * value (>=0) 616 * if namep is non-NULL *namep contiains a pointer to the property 617 * name. 618 * NULL, on error 619 * if lenp is non-NULL, *lenp contains an error code (<0): 620 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag 621 * -FDT_ERR_BADMAGIC, 622 * -FDT_ERR_BADVERSION, 623 * -FDT_ERR_BADSTATE, 624 * -FDT_ERR_BADSTRUCTURE, 625 * -FDT_ERR_TRUNCATED, standard meanings 626 */ 627 const void *fdt_getprop_by_offset(const void *fdt, int offset, 628 const char **namep, int *lenp); 629 630 /** 631 * fdt_getprop_namelen - get property value based on substring 632 * @fdt: pointer to the device tree blob 633 * @nodeoffset: offset of the node whose property to find 634 * @name: name of the property to find 635 * @namelen: number of characters of name to consider 636 * @lenp: pointer to an integer variable (will be overwritten) or NULL 637 * 638 * Identical to fdt_getprop(), but only examine the first namelen 639 * characters of name for matching the property name. 640 */ 641 const void *fdt_getprop_namelen(const void *fdt, int nodeoffset, 642 const char *name, int namelen, int *lenp); 643 static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset, 644 const char *name, int namelen, 645 int *lenp) 646 { 647 return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name, 648 namelen, lenp); 649 } 650 651 /** 652 * fdt_getprop - retrieve the value of a given property 653 * @fdt: pointer to the device tree blob 654 * @nodeoffset: offset of the node whose property to find 655 * @name: name of the property to find 656 * @lenp: pointer to an integer variable (will be overwritten) or NULL 657 * 658 * fdt_getprop() retrieves a pointer to the value of the property 659 * named 'name' of the node at offset nodeoffset (this will be a 660 * pointer to within the device blob itself, not a copy of the value). 661 * If lenp is non-NULL, the length of the property value is also 662 * returned, in the integer pointed to by lenp. 663 * 664 * returns: 665 * pointer to the property's value 666 * if lenp is non-NULL, *lenp contains the length of the property 667 * value (>=0) 668 * NULL, on error 669 * if lenp is non-NULL, *lenp contains an error code (<0): 670 * -FDT_ERR_NOTFOUND, node does not have named property 671 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE 672 * tag 673 * -FDT_ERR_BADMAGIC, 674 * -FDT_ERR_BADVERSION, 675 * -FDT_ERR_BADSTATE, 676 * -FDT_ERR_BADSTRUCTURE, 677 * -FDT_ERR_TRUNCATED, standard meanings 678 */ 679 const void *fdt_getprop(const void *fdt, int nodeoffset, 680 const char *name, int *lenp); 681 static inline void *fdt_getprop_w(void *fdt, int nodeoffset, 682 const char *name, int *lenp) 683 { 684 return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp); 685 } 686 687 /** 688 * fdt_get_phandle - retrieve the phandle of a given node 689 * @fdt: pointer to the device tree blob 690 * @nodeoffset: structure block offset of the node 691 * 692 * fdt_get_phandle() retrieves the phandle of the device tree node at 693 * structure block offset nodeoffset. 694 * 695 * returns: 696 * the phandle of the node at nodeoffset, on success (!= 0, != -1) 697 * 0, if the node has no phandle, or another error occurs 698 */ 699 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset); 700 701 /** 702 * fdt_get_alias_namelen - get alias based on substring 703 * @fdt: pointer to the device tree blob 704 * @name: name of the alias th look up 705 * @namelen: number of characters of name to consider 706 * 707 * Identical to fdt_get_alias(), but only examine the first namelen 708 * characters of name for matching the alias name. 709 */ 710 const char *fdt_get_alias_namelen(const void *fdt, 711 const char *name, int namelen); 712 713 /** 714 * fdt_get_alias - retrieve the path referenced by a given alias 715 * @fdt: pointer to the device tree blob 716 * @name: name of the alias th look up 717 * 718 * fdt_get_alias() retrieves the value of a given alias. That is, the 719 * value of the property named 'name' in the node /aliases. 720 * 721 * returns: 722 * a pointer to the expansion of the alias named 'name', if it exists 723 * NULL, if the given alias or the /aliases node does not exist 724 */ 725 const char *fdt_get_alias(const void *fdt, const char *name); 726 727 /** 728 * fdt_get_path - determine the full path of a node 729 * @fdt: pointer to the device tree blob 730 * @nodeoffset: offset of the node whose path to find 731 * @buf: character buffer to contain the returned path (will be overwritten) 732 * @buflen: size of the character buffer at buf 733 * 734 * fdt_get_path() computes the full path of the node at offset 735 * nodeoffset, and records that path in the buffer at buf. 736 * 737 * NOTE: This function is expensive, as it must scan the device tree 738 * structure from the start to nodeoffset. 739 * 740 * returns: 741 * 0, on success 742 * buf contains the absolute path of the node at 743 * nodeoffset, as a NUL-terminated string. 744 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag 745 * -FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1) 746 * characters and will not fit in the given buffer. 747 * -FDT_ERR_BADMAGIC, 748 * -FDT_ERR_BADVERSION, 749 * -FDT_ERR_BADSTATE, 750 * -FDT_ERR_BADSTRUCTURE, standard meanings 751 */ 752 int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen); 753 754 /** 755 * fdt_supernode_atdepth_offset - find a specific ancestor of a node 756 * @fdt: pointer to the device tree blob 757 * @nodeoffset: offset of the node whose parent to find 758 * @supernodedepth: depth of the ancestor to find 759 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL 760 * 761 * fdt_supernode_atdepth_offset() finds an ancestor of the given node 762 * at a specific depth from the root (where the root itself has depth 763 * 0, its immediate subnodes depth 1 and so forth). So 764 * fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL); 765 * will always return 0, the offset of the root node. If the node at 766 * nodeoffset has depth D, then: 767 * fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL); 768 * will return nodeoffset itself. 769 * 770 * NOTE: This function is expensive, as it must scan the device tree 771 * structure from the start to nodeoffset. 772 * 773 * returns: 774 * structure block offset of the node at node offset's ancestor 775 * of depth supernodedepth (>=0), on success 776 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag 777 * -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of 778 * nodeoffset 779 * -FDT_ERR_BADMAGIC, 780 * -FDT_ERR_BADVERSION, 781 * -FDT_ERR_BADSTATE, 782 * -FDT_ERR_BADSTRUCTURE, standard meanings 783 */ 784 int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset, 785 int supernodedepth, int *nodedepth); 786 787 /** 788 * fdt_node_depth - find the depth of a given node 789 * @fdt: pointer to the device tree blob 790 * @nodeoffset: offset of the node whose parent to find 791 * 792 * fdt_node_depth() finds the depth of a given node. The root node 793 * has depth 0, its immediate subnodes depth 1 and so forth. 794 * 795 * NOTE: This function is expensive, as it must scan the device tree 796 * structure from the start to nodeoffset. 797 * 798 * returns: 799 * depth of the node at nodeoffset (>=0), on success 800 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag 801 * -FDT_ERR_BADMAGIC, 802 * -FDT_ERR_BADVERSION, 803 * -FDT_ERR_BADSTATE, 804 * -FDT_ERR_BADSTRUCTURE, standard meanings 805 */ 806 int fdt_node_depth(const void *fdt, int nodeoffset); 807 808 /** 809 * fdt_parent_offset - find the parent of a given node 810 * @fdt: pointer to the device tree blob 811 * @nodeoffset: offset of the node whose parent to find 812 * 813 * fdt_parent_offset() locates the parent node of a given node (that 814 * is, it finds the offset of the node which contains the node at 815 * nodeoffset as a subnode). 816 * 817 * NOTE: This function is expensive, as it must scan the device tree 818 * structure from the start to nodeoffset, *twice*. 819 * 820 * returns: 821 * structure block offset of the parent of the node at nodeoffset 822 * (>=0), on success 823 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag 824 * -FDT_ERR_BADMAGIC, 825 * -FDT_ERR_BADVERSION, 826 * -FDT_ERR_BADSTATE, 827 * -FDT_ERR_BADSTRUCTURE, standard meanings 828 */ 829 int fdt_parent_offset(const void *fdt, int nodeoffset); 830 831 /** 832 * fdt_node_offset_by_prop_value - find nodes with a given property value 833 * @fdt: pointer to the device tree blob 834 * @startoffset: only find nodes after this offset 835 * @propname: property name to check 836 * @propval: property value to search for 837 * @proplen: length of the value in propval 838 * 839 * fdt_node_offset_by_prop_value() returns the offset of the first 840 * node after startoffset, which has a property named propname whose 841 * value is of length proplen and has value equal to propval; or if 842 * startoffset is -1, the very first such node in the tree. 843 * 844 * To iterate through all nodes matching the criterion, the following 845 * idiom can be used: 846 * offset = fdt_node_offset_by_prop_value(fdt, -1, propname, 847 * propval, proplen); 848 * while (offset != -FDT_ERR_NOTFOUND) { 849 * // other code here 850 * offset = fdt_node_offset_by_prop_value(fdt, offset, propname, 851 * propval, proplen); 852 * } 853 * 854 * Note the -1 in the first call to the function, if 0 is used here 855 * instead, the function will never locate the root node, even if it 856 * matches the criterion. 857 * 858 * returns: 859 * structure block offset of the located node (>= 0, >startoffset), 860 * on success 861 * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the 862 * tree after startoffset 863 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag 864 * -FDT_ERR_BADMAGIC, 865 * -FDT_ERR_BADVERSION, 866 * -FDT_ERR_BADSTATE, 867 * -FDT_ERR_BADSTRUCTURE, standard meanings 868 */ 869 int fdt_node_offset_by_prop_value(const void *fdt, int startoffset, 870 const char *propname, 871 const void *propval, int proplen); 872 873 /** 874 * fdt_node_offset_by_phandle - find the node with a given phandle 875 * @fdt: pointer to the device tree blob 876 * @phandle: phandle value 877 * 878 * fdt_node_offset_by_phandle() returns the offset of the node 879 * which has the given phandle value. If there is more than one node 880 * in the tree with the given phandle (an invalid tree), results are 881 * undefined. 882 * 883 * returns: 884 * structure block offset of the located node (>= 0), on success 885 * -FDT_ERR_NOTFOUND, no node with that phandle exists 886 * -FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1) 887 * -FDT_ERR_BADMAGIC, 888 * -FDT_ERR_BADVERSION, 889 * -FDT_ERR_BADSTATE, 890 * -FDT_ERR_BADSTRUCTURE, standard meanings 891 */ 892 int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle); 893 894 /** 895 * fdt_node_check_compatible: check a node's compatible property 896 * @fdt: pointer to the device tree blob 897 * @nodeoffset: offset of a tree node 898 * @compatible: string to match against 899 * 900 * 901 * fdt_node_check_compatible() returns 0 if the given node contains a 902 * 'compatible' property with the given string as one of its elements, 903 * it returns non-zero otherwise, or on error. 904 * 905 * returns: 906 * 0, if the node has a 'compatible' property listing the given string 907 * 1, if the node has a 'compatible' property, but it does not list 908 * the given string 909 * -FDT_ERR_NOTFOUND, if the given node has no 'compatible' property 910 * -FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag 911 * -FDT_ERR_BADMAGIC, 912 * -FDT_ERR_BADVERSION, 913 * -FDT_ERR_BADSTATE, 914 * -FDT_ERR_BADSTRUCTURE, standard meanings 915 */ 916 int fdt_node_check_compatible(const void *fdt, int nodeoffset, 917 const char *compatible); 918 919 /** 920 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value 921 * @fdt: pointer to the device tree blob 922 * @startoffset: only find nodes after this offset 923 * @compatible: 'compatible' string to match against 924 * 925 * fdt_node_offset_by_compatible() returns the offset of the first 926 * node after startoffset, which has a 'compatible' property which 927 * lists the given compatible string; or if startoffset is -1, the 928 * very first such node in the tree. 929 * 930 * To iterate through all nodes matching the criterion, the following 931 * idiom can be used: 932 * offset = fdt_node_offset_by_compatible(fdt, -1, compatible); 933 * while (offset != -FDT_ERR_NOTFOUND) { 934 * // other code here 935 * offset = fdt_node_offset_by_compatible(fdt, offset, compatible); 936 * } 937 * 938 * Note the -1 in the first call to the function, if 0 is used here 939 * instead, the function will never locate the root node, even if it 940 * matches the criterion. 941 * 942 * returns: 943 * structure block offset of the located node (>= 0, >startoffset), 944 * on success 945 * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the 946 * tree after startoffset 947 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag 948 * -FDT_ERR_BADMAGIC, 949 * -FDT_ERR_BADVERSION, 950 * -FDT_ERR_BADSTATE, 951 * -FDT_ERR_BADSTRUCTURE, standard meanings 952 */ 953 int fdt_node_offset_by_compatible(const void *fdt, int startoffset, 954 const char *compatible); 955 956 /** 957 * fdt_stringlist_contains - check a string list property for a string 958 * @strlist: Property containing a list of strings to check 959 * @listlen: Length of property 960 * @str: String to search for 961 * 962 * This is a utility function provided for convenience. The list contains 963 * one or more strings, each terminated by \0, as is found in a device tree 964 * "compatible" property. 965 * 966 * @return: 1 if the string is found in the list, 0 not found, or invalid list 967 */ 968 int fdt_stringlist_contains(const char *strlist, int listlen, const char *str); 969 970 /** 971 * fdt_stringlist_count - count the number of strings in a string list 972 * @fdt: pointer to the device tree blob 973 * @nodeoffset: offset of a tree node 974 * @property: name of the property containing the string list 975 * @return: 976 * the number of strings in the given property 977 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated 978 * -FDT_ERR_NOTFOUND if the property does not exist 979 */ 980 int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property); 981 982 /** 983 * fdt_stringlist_search - find a string in a string list and return its index 984 * @fdt: pointer to the device tree blob 985 * @nodeoffset: offset of a tree node 986 * @property: name of the property containing the string list 987 * @string: string to look up in the string list 988 * 989 * Note that it is possible for this function to succeed on property values 990 * that are not NUL-terminated. That's because the function will stop after 991 * finding the first occurrence of @string. This can for example happen with 992 * small-valued cell properties, such as #address-cells, when searching for 993 * the empty string. 994 * 995 * @return: 996 * the index of the string in the list of strings 997 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated 998 * -FDT_ERR_NOTFOUND if the property does not exist or does not contain 999 * the given string 1000 */ 1001 int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property, 1002 const char *string); 1003 1004 /** 1005 * fdt_stringlist_get() - obtain the string at a given index in a string list 1006 * @fdt: pointer to the device tree blob 1007 * @nodeoffset: offset of a tree node 1008 * @property: name of the property containing the string list 1009 * @index: index of the string to return 1010 * @lenp: return location for the string length or an error code on failure 1011 * 1012 * Note that this will successfully extract strings from properties with 1013 * non-NUL-terminated values. For example on small-valued cell properties 1014 * this function will return the empty string. 1015 * 1016 * If non-NULL, the length of the string (on success) or a negative error-code 1017 * (on failure) will be stored in the integer pointer to by lenp. 1018 * 1019 * @return: 1020 * A pointer to the string at the given index in the string list or NULL on 1021 * failure. On success the length of the string will be stored in the memory 1022 * location pointed to by the lenp parameter, if non-NULL. On failure one of 1023 * the following negative error codes will be returned in the lenp parameter 1024 * (if non-NULL): 1025 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated 1026 * -FDT_ERR_NOTFOUND if the property does not exist 1027 */ 1028 const char *fdt_stringlist_get(const void *fdt, int nodeoffset, 1029 const char *property, int index, 1030 int *lenp); 1031 1032 /**********************************************************************/ 1033 /* Read-only functions (addressing related) */ 1034 /**********************************************************************/ 1035 1036 /** 1037 * FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells 1038 * 1039 * This is the maximum value for #address-cells, #size-cells and 1040 * similar properties that will be processed by libfdt. IEE1275 1041 * requires that OF implementations handle values up to 4. 1042 * Implementations may support larger values, but in practice higher 1043 * values aren't used. 1044 */ 1045 #define FDT_MAX_NCELLS 4 1046 1047 /** 1048 * fdt_address_cells - retrieve address size for a bus represented in the tree 1049 * @fdt: pointer to the device tree blob 1050 * @nodeoffset: offset of the node to find the address size for 1051 * 1052 * When the node has a valid #address-cells property, returns its value. 1053 * 1054 * returns: 1055 * 0 <= n < FDT_MAX_NCELLS, on success 1056 * 2, if the node has no #address-cells property 1057 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid 1058 * #address-cells property 1059 * -FDT_ERR_BADMAGIC, 1060 * -FDT_ERR_BADVERSION, 1061 * -FDT_ERR_BADSTATE, 1062 * -FDT_ERR_BADSTRUCTURE, 1063 * -FDT_ERR_TRUNCATED, standard meanings 1064 */ 1065 int fdt_address_cells(const void *fdt, int nodeoffset); 1066 1067 /** 1068 * fdt_size_cells - retrieve address range size for a bus represented in the 1069 * tree 1070 * @fdt: pointer to the device tree blob 1071 * @nodeoffset: offset of the node to find the address range size for 1072 * 1073 * When the node has a valid #size-cells property, returns its value. 1074 * 1075 * returns: 1076 * 0 <= n < FDT_MAX_NCELLS, on success 1077 * 2, if the node has no #address-cells property 1078 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid 1079 * #size-cells property 1080 * -FDT_ERR_BADMAGIC, 1081 * -FDT_ERR_BADVERSION, 1082 * -FDT_ERR_BADSTATE, 1083 * -FDT_ERR_BADSTRUCTURE, 1084 * -FDT_ERR_TRUNCATED, standard meanings 1085 */ 1086 int fdt_size_cells(const void *fdt, int nodeoffset); 1087 1088 1089 /**********************************************************************/ 1090 /* Write-in-place functions */ 1091 /**********************************************************************/ 1092 1093 /** 1094 * fdt_setprop_inplace_namelen_partial - change a property's value, 1095 * but not its size 1096 * @fdt: pointer to the device tree blob 1097 * @nodeoffset: offset of the node whose property to change 1098 * @name: name of the property to change 1099 * @namelen: number of characters of name to consider 1100 * @idx: index of the property to change in the array 1101 * @val: pointer to data to replace the property value with 1102 * @len: length of the property value 1103 * 1104 * Identical to fdt_setprop_inplace(), but modifies the given property 1105 * starting from the given index, and using only the first characters 1106 * of the name. It is useful when you want to manipulate only one value of 1107 * an array and you have a string that doesn't end with \0. 1108 */ 1109 int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset, 1110 const char *name, int namelen, 1111 uint32_t idx, const void *val, 1112 int len); 1113 1114 /** 1115 * fdt_setprop_inplace - change a property's value, but not its size 1116 * @fdt: pointer to the device tree blob 1117 * @nodeoffset: offset of the node whose property to change 1118 * @name: name of the property to change 1119 * @val: pointer to data to replace the property value with 1120 * @len: length of the property value 1121 * 1122 * fdt_setprop_inplace() replaces the value of a given property with 1123 * the data in val, of length len. This function cannot change the 1124 * size of a property, and so will only work if len is equal to the 1125 * current length of the property. 1126 * 1127 * This function will alter only the bytes in the blob which contain 1128 * the given property value, and will not alter or move any other part 1129 * of the tree. 1130 * 1131 * returns: 1132 * 0, on success 1133 * -FDT_ERR_NOSPACE, if len is not equal to the property's current length 1134 * -FDT_ERR_NOTFOUND, node does not have the named property 1135 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1136 * -FDT_ERR_BADMAGIC, 1137 * -FDT_ERR_BADVERSION, 1138 * -FDT_ERR_BADSTATE, 1139 * -FDT_ERR_BADSTRUCTURE, 1140 * -FDT_ERR_TRUNCATED, standard meanings 1141 */ 1142 int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name, 1143 const void *val, int len); 1144 1145 /** 1146 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property 1147 * @fdt: pointer to the device tree blob 1148 * @nodeoffset: offset of the node whose property to change 1149 * @name: name of the property to change 1150 * @val: 32-bit integer value to replace the property with 1151 * 1152 * fdt_setprop_inplace_u32() replaces the value of a given property 1153 * with the 32-bit integer value in val, converting val to big-endian 1154 * if necessary. This function cannot change the size of a property, 1155 * and so will only work if the property already exists and has length 1156 * 4. 1157 * 1158 * This function will alter only the bytes in the blob which contain 1159 * the given property value, and will not alter or move any other part 1160 * of the tree. 1161 * 1162 * returns: 1163 * 0, on success 1164 * -FDT_ERR_NOSPACE, if the property's length is not equal to 4 1165 * -FDT_ERR_NOTFOUND, node does not have the named property 1166 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1167 * -FDT_ERR_BADMAGIC, 1168 * -FDT_ERR_BADVERSION, 1169 * -FDT_ERR_BADSTATE, 1170 * -FDT_ERR_BADSTRUCTURE, 1171 * -FDT_ERR_TRUNCATED, standard meanings 1172 */ 1173 static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset, 1174 const char *name, uint32_t val) 1175 { 1176 fdt32_t tmp = cpu_to_fdt32(val); 1177 return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp)); 1178 } 1179 1180 /** 1181 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property 1182 * @fdt: pointer to the device tree blob 1183 * @nodeoffset: offset of the node whose property to change 1184 * @name: name of the property to change 1185 * @val: 64-bit integer value to replace the property with 1186 * 1187 * fdt_setprop_inplace_u64() replaces the value of a given property 1188 * with the 64-bit integer value in val, converting val to big-endian 1189 * if necessary. This function cannot change the size of a property, 1190 * and so will only work if the property already exists and has length 1191 * 8. 1192 * 1193 * This function will alter only the bytes in the blob which contain 1194 * the given property value, and will not alter or move any other part 1195 * of the tree. 1196 * 1197 * returns: 1198 * 0, on success 1199 * -FDT_ERR_NOSPACE, if the property's length is not equal to 8 1200 * -FDT_ERR_NOTFOUND, node does not have the named property 1201 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1202 * -FDT_ERR_BADMAGIC, 1203 * -FDT_ERR_BADVERSION, 1204 * -FDT_ERR_BADSTATE, 1205 * -FDT_ERR_BADSTRUCTURE, 1206 * -FDT_ERR_TRUNCATED, standard meanings 1207 */ 1208 static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset, 1209 const char *name, uint64_t val) 1210 { 1211 fdt64_t tmp = cpu_to_fdt64(val); 1212 return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp)); 1213 } 1214 1215 /** 1216 * fdt_setprop_inplace_cell - change the value of a single-cell property 1217 * 1218 * This is an alternative name for fdt_setprop_inplace_u32() 1219 */ 1220 static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset, 1221 const char *name, uint32_t val) 1222 { 1223 return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val); 1224 } 1225 1226 /** 1227 * fdt_nop_property - replace a property with nop tags 1228 * @fdt: pointer to the device tree blob 1229 * @nodeoffset: offset of the node whose property to nop 1230 * @name: name of the property to nop 1231 * 1232 * fdt_nop_property() will replace a given property's representation 1233 * in the blob with FDT_NOP tags, effectively removing it from the 1234 * tree. 1235 * 1236 * This function will alter only the bytes in the blob which contain 1237 * the property, and will not alter or move any other part of the 1238 * tree. 1239 * 1240 * returns: 1241 * 0, on success 1242 * -FDT_ERR_NOTFOUND, node does not have the named property 1243 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1244 * -FDT_ERR_BADMAGIC, 1245 * -FDT_ERR_BADVERSION, 1246 * -FDT_ERR_BADSTATE, 1247 * -FDT_ERR_BADSTRUCTURE, 1248 * -FDT_ERR_TRUNCATED, standard meanings 1249 */ 1250 int fdt_nop_property(void *fdt, int nodeoffset, const char *name); 1251 1252 /** 1253 * fdt_nop_node - replace a node (subtree) with nop tags 1254 * @fdt: pointer to the device tree blob 1255 * @nodeoffset: offset of the node to nop 1256 * 1257 * fdt_nop_node() will replace a given node's representation in the 1258 * blob, including all its subnodes, if any, with FDT_NOP tags, 1259 * effectively removing it from the tree. 1260 * 1261 * This function will alter only the bytes in the blob which contain 1262 * the node and its properties and subnodes, and will not alter or 1263 * move any other part of the tree. 1264 * 1265 * returns: 1266 * 0, on success 1267 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1268 * -FDT_ERR_BADMAGIC, 1269 * -FDT_ERR_BADVERSION, 1270 * -FDT_ERR_BADSTATE, 1271 * -FDT_ERR_BADSTRUCTURE, 1272 * -FDT_ERR_TRUNCATED, standard meanings 1273 */ 1274 int fdt_nop_node(void *fdt, int nodeoffset); 1275 1276 /**********************************************************************/ 1277 /* Sequential write functions */ 1278 /**********************************************************************/ 1279 1280 int fdt_create(void *buf, int bufsize); 1281 int fdt_resize(void *fdt, void *buf, int bufsize); 1282 int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size); 1283 int fdt_finish_reservemap(void *fdt); 1284 int fdt_begin_node(void *fdt, const char *name); 1285 int fdt_property(void *fdt, const char *name, const void *val, int len); 1286 static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val) 1287 { 1288 fdt32_t tmp = cpu_to_fdt32(val); 1289 return fdt_property(fdt, name, &tmp, sizeof(tmp)); 1290 } 1291 static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val) 1292 { 1293 fdt64_t tmp = cpu_to_fdt64(val); 1294 return fdt_property(fdt, name, &tmp, sizeof(tmp)); 1295 } 1296 static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val) 1297 { 1298 return fdt_property_u32(fdt, name, val); 1299 } 1300 #define fdt_property_string(fdt, name, str) \ 1301 fdt_property(fdt, name, str, strlen(str)+1) 1302 int fdt_end_node(void *fdt); 1303 int fdt_finish(void *fdt); 1304 1305 /**********************************************************************/ 1306 /* Read-write functions */ 1307 /**********************************************************************/ 1308 1309 int fdt_create_empty_tree(void *buf, int bufsize); 1310 int fdt_open_into(const void *fdt, void *buf, int bufsize); 1311 int fdt_pack(void *fdt); 1312 1313 /** 1314 * fdt_add_mem_rsv - add one memory reserve map entry 1315 * @fdt: pointer to the device tree blob 1316 * @address, @size: 64-bit values (native endian) 1317 * 1318 * Adds a reserve map entry to the given blob reserving a region at 1319 * address address of length size. 1320 * 1321 * This function will insert data into the reserve map and will 1322 * therefore change the indexes of some entries in the table. 1323 * 1324 * returns: 1325 * 0, on success 1326 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to 1327 * contain the new reservation entry 1328 * -FDT_ERR_BADMAGIC, 1329 * -FDT_ERR_BADVERSION, 1330 * -FDT_ERR_BADSTATE, 1331 * -FDT_ERR_BADSTRUCTURE, 1332 * -FDT_ERR_BADLAYOUT, 1333 * -FDT_ERR_TRUNCATED, standard meanings 1334 */ 1335 int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size); 1336 1337 /** 1338 * fdt_del_mem_rsv - remove a memory reserve map entry 1339 * @fdt: pointer to the device tree blob 1340 * @n: entry to remove 1341 * 1342 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from 1343 * the blob. 1344 * 1345 * This function will delete data from the reservation table and will 1346 * therefore change the indexes of some entries in the table. 1347 * 1348 * returns: 1349 * 0, on success 1350 * -FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there 1351 * are less than n+1 reserve map entries) 1352 * -FDT_ERR_BADMAGIC, 1353 * -FDT_ERR_BADVERSION, 1354 * -FDT_ERR_BADSTATE, 1355 * -FDT_ERR_BADSTRUCTURE, 1356 * -FDT_ERR_BADLAYOUT, 1357 * -FDT_ERR_TRUNCATED, standard meanings 1358 */ 1359 int fdt_del_mem_rsv(void *fdt, int n); 1360 1361 /** 1362 * fdt_set_name - change the name of a given node 1363 * @fdt: pointer to the device tree blob 1364 * @nodeoffset: structure block offset of a node 1365 * @name: name to give the node 1366 * 1367 * fdt_set_name() replaces the name (including unit address, if any) 1368 * of the given node with the given string. NOTE: this function can't 1369 * efficiently check if the new name is unique amongst the given 1370 * node's siblings; results are undefined if this function is invoked 1371 * with a name equal to one of the given node's siblings. 1372 * 1373 * This function may insert or delete data from the blob, and will 1374 * therefore change the offsets of some existing nodes. 1375 * 1376 * returns: 1377 * 0, on success 1378 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob 1379 * to contain the new name 1380 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1381 * -FDT_ERR_BADMAGIC, 1382 * -FDT_ERR_BADVERSION, 1383 * -FDT_ERR_BADSTATE, standard meanings 1384 */ 1385 int fdt_set_name(void *fdt, int nodeoffset, const char *name); 1386 1387 /** 1388 * fdt_setprop - create or change a property 1389 * @fdt: pointer to the device tree blob 1390 * @nodeoffset: offset of the node whose property to change 1391 * @name: name of the property to change 1392 * @val: pointer to data to set the property value to 1393 * @len: length of the property value 1394 * 1395 * fdt_setprop() sets the value of the named property in the given 1396 * node to the given value and length, creating the property if it 1397 * does not already exist. 1398 * 1399 * This function may insert or delete data from the blob, and will 1400 * therefore change the offsets of some existing nodes. 1401 * 1402 * returns: 1403 * 0, on success 1404 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to 1405 * contain the new property value 1406 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1407 * -FDT_ERR_BADLAYOUT, 1408 * -FDT_ERR_BADMAGIC, 1409 * -FDT_ERR_BADVERSION, 1410 * -FDT_ERR_BADSTATE, 1411 * -FDT_ERR_BADSTRUCTURE, 1412 * -FDT_ERR_BADLAYOUT, 1413 * -FDT_ERR_TRUNCATED, standard meanings 1414 */ 1415 int fdt_setprop(void *fdt, int nodeoffset, const char *name, 1416 const void *val, int len); 1417 1418 /** 1419 * fdt_setprop_u32 - set a property to a 32-bit integer 1420 * @fdt: pointer to the device tree blob 1421 * @nodeoffset: offset of the node whose property to change 1422 * @name: name of the property to change 1423 * @val: 32-bit integer value for the property (native endian) 1424 * 1425 * fdt_setprop_u32() sets the value of the named property in the given 1426 * node to the given 32-bit integer value (converting to big-endian if 1427 * necessary), or creates a new property with that value if it does 1428 * not already exist. 1429 * 1430 * This function may insert or delete data from the blob, and will 1431 * therefore change the offsets of some existing nodes. 1432 * 1433 * returns: 1434 * 0, on success 1435 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to 1436 * contain the new property value 1437 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1438 * -FDT_ERR_BADLAYOUT, 1439 * -FDT_ERR_BADMAGIC, 1440 * -FDT_ERR_BADVERSION, 1441 * -FDT_ERR_BADSTATE, 1442 * -FDT_ERR_BADSTRUCTURE, 1443 * -FDT_ERR_BADLAYOUT, 1444 * -FDT_ERR_TRUNCATED, standard meanings 1445 */ 1446 static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name, 1447 uint32_t val) 1448 { 1449 fdt32_t tmp = cpu_to_fdt32(val); 1450 return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp)); 1451 } 1452 1453 /** 1454 * fdt_setprop_u64 - set a property to a 64-bit integer 1455 * @fdt: pointer to the device tree blob 1456 * @nodeoffset: offset of the node whose property to change 1457 * @name: name of the property to change 1458 * @val: 64-bit integer value for the property (native endian) 1459 * 1460 * fdt_setprop_u64() sets the value of the named property in the given 1461 * node to the given 64-bit integer value (converting to big-endian if 1462 * necessary), or creates a new property with that value if it does 1463 * not already exist. 1464 * 1465 * This function may insert or delete data from the blob, and will 1466 * therefore change the offsets of some existing nodes. 1467 * 1468 * returns: 1469 * 0, on success 1470 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to 1471 * contain the new property value 1472 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1473 * -FDT_ERR_BADLAYOUT, 1474 * -FDT_ERR_BADMAGIC, 1475 * -FDT_ERR_BADVERSION, 1476 * -FDT_ERR_BADSTATE, 1477 * -FDT_ERR_BADSTRUCTURE, 1478 * -FDT_ERR_BADLAYOUT, 1479 * -FDT_ERR_TRUNCATED, standard meanings 1480 */ 1481 static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name, 1482 uint64_t val) 1483 { 1484 fdt64_t tmp = cpu_to_fdt64(val); 1485 return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp)); 1486 } 1487 1488 /** 1489 * fdt_setprop_cell - set a property to a single cell value 1490 * 1491 * This is an alternative name for fdt_setprop_u32() 1492 */ 1493 static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name, 1494 uint32_t val) 1495 { 1496 return fdt_setprop_u32(fdt, nodeoffset, name, val); 1497 } 1498 1499 /** 1500 * fdt_setprop_string - set a property to a string value 1501 * @fdt: pointer to the device tree blob 1502 * @nodeoffset: offset of the node whose property to change 1503 * @name: name of the property to change 1504 * @str: string value for the property 1505 * 1506 * fdt_setprop_string() sets the value of the named property in the 1507 * given node to the given string value (using the length of the 1508 * string to determine the new length of the property), or creates a 1509 * new property with that value if it does not already exist. 1510 * 1511 * This function may insert or delete data from the blob, and will 1512 * therefore change the offsets of some existing nodes. 1513 * 1514 * returns: 1515 * 0, on success 1516 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to 1517 * contain the new property value 1518 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1519 * -FDT_ERR_BADLAYOUT, 1520 * -FDT_ERR_BADMAGIC, 1521 * -FDT_ERR_BADVERSION, 1522 * -FDT_ERR_BADSTATE, 1523 * -FDT_ERR_BADSTRUCTURE, 1524 * -FDT_ERR_BADLAYOUT, 1525 * -FDT_ERR_TRUNCATED, standard meanings 1526 */ 1527 #define fdt_setprop_string(fdt, nodeoffset, name, str) \ 1528 fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1) 1529 1530 /** 1531 * fdt_appendprop - append to or create a property 1532 * @fdt: pointer to the device tree blob 1533 * @nodeoffset: offset of the node whose property to change 1534 * @name: name of the property to append to 1535 * @val: pointer to data to append to the property value 1536 * @len: length of the data to append to the property value 1537 * 1538 * fdt_appendprop() appends the value to the named property in the 1539 * given node, creating the property if it does not already exist. 1540 * 1541 * This function may insert data into the blob, and will therefore 1542 * change the offsets of some existing nodes. 1543 * 1544 * returns: 1545 * 0, on success 1546 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to 1547 * contain the new property value 1548 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1549 * -FDT_ERR_BADLAYOUT, 1550 * -FDT_ERR_BADMAGIC, 1551 * -FDT_ERR_BADVERSION, 1552 * -FDT_ERR_BADSTATE, 1553 * -FDT_ERR_BADSTRUCTURE, 1554 * -FDT_ERR_BADLAYOUT, 1555 * -FDT_ERR_TRUNCATED, standard meanings 1556 */ 1557 int fdt_appendprop(void *fdt, int nodeoffset, const char *name, 1558 const void *val, int len); 1559 1560 /** 1561 * fdt_appendprop_u32 - append a 32-bit integer value to a property 1562 * @fdt: pointer to the device tree blob 1563 * @nodeoffset: offset of the node whose property to change 1564 * @name: name of the property to change 1565 * @val: 32-bit integer value to append to the property (native endian) 1566 * 1567 * fdt_appendprop_u32() appends the given 32-bit integer value 1568 * (converting to big-endian if necessary) to the value of the named 1569 * property in the given node, or creates a new property with that 1570 * value if it does not already exist. 1571 * 1572 * This function may insert data into the blob, and will therefore 1573 * change the offsets of some existing nodes. 1574 * 1575 * returns: 1576 * 0, on success 1577 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to 1578 * contain the new property value 1579 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1580 * -FDT_ERR_BADLAYOUT, 1581 * -FDT_ERR_BADMAGIC, 1582 * -FDT_ERR_BADVERSION, 1583 * -FDT_ERR_BADSTATE, 1584 * -FDT_ERR_BADSTRUCTURE, 1585 * -FDT_ERR_BADLAYOUT, 1586 * -FDT_ERR_TRUNCATED, standard meanings 1587 */ 1588 static inline int fdt_appendprop_u32(void *fdt, int nodeoffset, 1589 const char *name, uint32_t val) 1590 { 1591 fdt32_t tmp = cpu_to_fdt32(val); 1592 return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp)); 1593 } 1594 1595 /** 1596 * fdt_appendprop_u64 - append a 64-bit integer value to a property 1597 * @fdt: pointer to the device tree blob 1598 * @nodeoffset: offset of the node whose property to change 1599 * @name: name of the property to change 1600 * @val: 64-bit integer value to append to the property (native endian) 1601 * 1602 * fdt_appendprop_u64() appends the given 64-bit integer value 1603 * (converting to big-endian if necessary) to the value of the named 1604 * property in the given node, or creates a new property with that 1605 * value if it does not already exist. 1606 * 1607 * This function may insert data into the blob, and will therefore 1608 * change the offsets of some existing nodes. 1609 * 1610 * returns: 1611 * 0, on success 1612 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to 1613 * contain the new property value 1614 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1615 * -FDT_ERR_BADLAYOUT, 1616 * -FDT_ERR_BADMAGIC, 1617 * -FDT_ERR_BADVERSION, 1618 * -FDT_ERR_BADSTATE, 1619 * -FDT_ERR_BADSTRUCTURE, 1620 * -FDT_ERR_BADLAYOUT, 1621 * -FDT_ERR_TRUNCATED, standard meanings 1622 */ 1623 static inline int fdt_appendprop_u64(void *fdt, int nodeoffset, 1624 const char *name, uint64_t val) 1625 { 1626 fdt64_t tmp = cpu_to_fdt64(val); 1627 return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp)); 1628 } 1629 1630 /** 1631 * fdt_appendprop_cell - append a single cell value to a property 1632 * 1633 * This is an alternative name for fdt_appendprop_u32() 1634 */ 1635 static inline int fdt_appendprop_cell(void *fdt, int nodeoffset, 1636 const char *name, uint32_t val) 1637 { 1638 return fdt_appendprop_u32(fdt, nodeoffset, name, val); 1639 } 1640 1641 /** 1642 * fdt_appendprop_string - append a string to a property 1643 * @fdt: pointer to the device tree blob 1644 * @nodeoffset: offset of the node whose property to change 1645 * @name: name of the property to change 1646 * @str: string value to append to the property 1647 * 1648 * fdt_appendprop_string() appends the given string to the value of 1649 * the named property in the given node, or creates a new property 1650 * with that value if it does not already exist. 1651 * 1652 * This function may insert data into the blob, and will therefore 1653 * change the offsets of some existing nodes. 1654 * 1655 * returns: 1656 * 0, on success 1657 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to 1658 * contain the new property value 1659 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1660 * -FDT_ERR_BADLAYOUT, 1661 * -FDT_ERR_BADMAGIC, 1662 * -FDT_ERR_BADVERSION, 1663 * -FDT_ERR_BADSTATE, 1664 * -FDT_ERR_BADSTRUCTURE, 1665 * -FDT_ERR_BADLAYOUT, 1666 * -FDT_ERR_TRUNCATED, standard meanings 1667 */ 1668 #define fdt_appendprop_string(fdt, nodeoffset, name, str) \ 1669 fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1) 1670 1671 /** 1672 * fdt_delprop - delete a property 1673 * @fdt: pointer to the device tree blob 1674 * @nodeoffset: offset of the node whose property to nop 1675 * @name: name of the property to nop 1676 * 1677 * fdt_del_property() will delete the given property. 1678 * 1679 * This function will delete data from the blob, and will therefore 1680 * change the offsets of some existing nodes. 1681 * 1682 * returns: 1683 * 0, on success 1684 * -FDT_ERR_NOTFOUND, node does not have the named property 1685 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1686 * -FDT_ERR_BADLAYOUT, 1687 * -FDT_ERR_BADMAGIC, 1688 * -FDT_ERR_BADVERSION, 1689 * -FDT_ERR_BADSTATE, 1690 * -FDT_ERR_BADSTRUCTURE, 1691 * -FDT_ERR_TRUNCATED, standard meanings 1692 */ 1693 int fdt_delprop(void *fdt, int nodeoffset, const char *name); 1694 1695 /** 1696 * fdt_add_subnode_namelen - creates a new node based on substring 1697 * @fdt: pointer to the device tree blob 1698 * @parentoffset: structure block offset of a node 1699 * @name: name of the subnode to locate 1700 * @namelen: number of characters of name to consider 1701 * 1702 * Identical to fdt_add_subnode(), but use only the first namelen 1703 * characters of name as the name of the new node. This is useful for 1704 * creating subnodes based on a portion of a larger string, such as a 1705 * full path. 1706 */ 1707 int fdt_add_subnode_namelen(void *fdt, int parentoffset, 1708 const char *name, int namelen); 1709 1710 /** 1711 * fdt_add_subnode - creates a new node 1712 * @fdt: pointer to the device tree blob 1713 * @parentoffset: structure block offset of a node 1714 * @name: name of the subnode to locate 1715 * 1716 * fdt_add_subnode() creates a new node as a subnode of the node at 1717 * structure block offset parentoffset, with the given name (which 1718 * should include the unit address, if any). 1719 * 1720 * This function will insert data into the blob, and will therefore 1721 * change the offsets of some existing nodes. 1722 1723 * returns: 1724 * structure block offset of the created nodeequested subnode (>=0), on 1725 * success 1726 * -FDT_ERR_NOTFOUND, if the requested subnode does not exist 1727 * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE 1728 * tag 1729 * -FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of 1730 * the given name 1731 * -FDT_ERR_NOSPACE, if there is insufficient free space in the 1732 * blob to contain the new node 1733 * -FDT_ERR_NOSPACE 1734 * -FDT_ERR_BADLAYOUT 1735 * -FDT_ERR_BADMAGIC, 1736 * -FDT_ERR_BADVERSION, 1737 * -FDT_ERR_BADSTATE, 1738 * -FDT_ERR_BADSTRUCTURE, 1739 * -FDT_ERR_TRUNCATED, standard meanings. 1740 */ 1741 int fdt_add_subnode(void *fdt, int parentoffset, const char *name); 1742 1743 /** 1744 * fdt_del_node - delete a node (subtree) 1745 * @fdt: pointer to the device tree blob 1746 * @nodeoffset: offset of the node to nop 1747 * 1748 * fdt_del_node() will remove the given node, including all its 1749 * subnodes if any, from the blob. 1750 * 1751 * This function will delete data from the blob, and will therefore 1752 * change the offsets of some existing nodes. 1753 * 1754 * returns: 1755 * 0, on success 1756 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag 1757 * -FDT_ERR_BADLAYOUT, 1758 * -FDT_ERR_BADMAGIC, 1759 * -FDT_ERR_BADVERSION, 1760 * -FDT_ERR_BADSTATE, 1761 * -FDT_ERR_BADSTRUCTURE, 1762 * -FDT_ERR_TRUNCATED, standard meanings 1763 */ 1764 int fdt_del_node(void *fdt, int nodeoffset); 1765 1766 /** 1767 * fdt_overlay_apply - Applies a DT overlay on a base DT 1768 * @fdt: pointer to the base device tree blob 1769 * @fdto: pointer to the device tree overlay blob 1770 * 1771 * fdt_overlay_apply() will apply the given device tree overlay on the 1772 * given base device tree. 1773 * 1774 * Expect the base device tree to be modified, even if the function 1775 * returns an error. 1776 * 1777 * returns: 1778 * 0, on success 1779 * -FDT_ERR_NOSPACE, there's not enough space in the base device tree 1780 * -FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or 1781 * properties in the base DT 1782 * -FDT_ERR_BADPHANDLE, 1783 * -FDT_ERR_BADOVERLAY, 1784 * -FDT_ERR_NOPHANDLES, 1785 * -FDT_ERR_INTERNAL, 1786 * -FDT_ERR_BADLAYOUT, 1787 * -FDT_ERR_BADMAGIC, 1788 * -FDT_ERR_BADOFFSET, 1789 * -FDT_ERR_BADPATH, 1790 * -FDT_ERR_BADVERSION, 1791 * -FDT_ERR_BADSTRUCTURE, 1792 * -FDT_ERR_BADSTATE, 1793 * -FDT_ERR_TRUNCATED, standard meanings 1794 */ 1795 int fdt_overlay_apply(void *fdt, void *fdto); 1796 1797 /**********************************************************************/ 1798 /* Debugging / informational functions */ 1799 /**********************************************************************/ 1800 1801 const char *fdt_strerror(int errval); 1802 1803 #endif /* _LIBFDT_H */ 1804