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