include/libfdt.h

   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 #define FDT_ERR_MAX             13
 120
 121 /**********************************************************************/
 122 /* Low-level functions (you probably don't need these)                */
 123 /**********************************************************************/
 124
 125 const void *fdt_offset_ptr(const void *fdt, int offset, int checklen);
 126 static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
 127 {
 128         return (void *)fdt_offset_ptr(fdt, offset, checklen);
 129 }
 130
 131 uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
 132
 133 /**********************************************************************/
 134 /* Traversal functions                                                */
 135 /**********************************************************************/
 136
 137 int fdt_next_node(const void *fdt, int offset, int *depth);
 138
 139 /**********************************************************************/
 140 /* General functions                                                  */
 141 /**********************************************************************/
 142
 143 #define fdt_get_header(fdt, field) \
 144         (fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
 145 #define fdt_magic(fdt)                  (fdt_get_header(fdt, magic))
 146 #define fdt_totalsize(fdt)              (fdt_get_header(fdt, totalsize))
 147 #define fdt_off_dt_struct(fdt)          (fdt_get_header(fdt, off_dt_struct))
 148 #define fdt_off_dt_strings(fdt)         (fdt_get_header(fdt, off_dt_strings))
 149 #define fdt_off_mem_rsvmap(fdt)         (fdt_get_header(fdt, off_mem_rsvmap))
 150 #define fdt_version(fdt)                (fdt_get_header(fdt, version))
 151 #define fdt_last_comp_version(fdt)      (fdt_get_header(fdt, last_comp_version))
 152 #define fdt_boot_cpuid_phys(fdt)        (fdt_get_header(fdt, boot_cpuid_phys))
 153 #define fdt_size_dt_strings(fdt)        (fdt_get_header(fdt, size_dt_strings))
 154 #define fdt_size_dt_struct(fdt)         (fdt_get_header(fdt, size_dt_struct))
 155
 156 #define __fdt_set_hdr(name) \
 157         static inline void fdt_set_##name(void *fdt, uint32_t val) \
 158         { \
 159                 struct fdt_header *fdth = fdt; \
 160                 fdth->name = cpu_to_fdt32(val); \
 161         }
 162 __fdt_set_hdr(magic);
 163 __fdt_set_hdr(totalsize);
 164 __fdt_set_hdr(off_dt_struct);
 165 __fdt_set_hdr(off_dt_strings);
 166 __fdt_set_hdr(off_mem_rsvmap);
 167 __fdt_set_hdr(version);
 168 __fdt_set_hdr(last_comp_version);
 169 __fdt_set_hdr(boot_cpuid_phys);
 170 __fdt_set_hdr(size_dt_strings);
 171 __fdt_set_hdr(size_dt_struct);
 172 #undef __fdt_set_hdr
 173
 174 /**
 175  * fdt_check_header - sanity check a device tree or possible device tree
 176  * @fdt: pointer to data which might be a flattened device tree
 177  *
 178  * fdt_check_header() checks that the given buffer contains what
 179  * appears to be a flattened device tree with sane information in its
 180  * header.
 181  *
 182  * returns:
 183  *     0, if the buffer appears to contain a valid device tree
 184  *     -FDT_ERR_BADMAGIC,
 185  *     -FDT_ERR_BADVERSION,
 186  *     -FDT_ERR_BADSTATE, standard meanings, as above
 187  */
 188 int fdt_check_header(const void *fdt);
 189
 190 /**
 191  * fdt_move - move a device tree around in memory
 192  * @fdt: pointer to the device tree to move
 193  * @buf: pointer to memory where the device is to be moved
 194  * @bufsize: size of the memory space at buf
 195  *
 196  * fdt_move() relocates, if possible, the device tree blob located at
 197  * fdt to the buffer at buf of size bufsize.  The buffer may overlap
 198  * with the existing device tree blob at fdt.  Therefore,
 199  *     fdt_move(fdt, fdt, fdt_totalsize(fdt))
 200  * should always succeed.
 201  *
 202  * returns:
 203  *     0, on success
 204  *     -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
 205  *     -FDT_ERR_BADMAGIC,
 206  *     -FDT_ERR_BADVERSION,
 207  *     -FDT_ERR_BADSTATE, standard meanings
 208  */
 209 int fdt_move(const void *fdt, void *buf, int bufsize);
 210
 211 /**********************************************************************/
 212 /* Read-only functions                                                */
 213 /**********************************************************************/
 214
 215 /**
 216  * fdt_string - retreive a string from the strings block of a device tree
 217  * @fdt: pointer to the device tree blob
 218  * @stroffset: offset of the string within the strings block (native endian)
 219  *
 220  * fdt_string() retrieves a pointer to a single string from the
 221  * strings block of the device tree blob at fdt.
 222  *
 223  * returns:
 224  *     a pointer to the string, on success
 225  *     NULL, if stroffset is out of bounds
 226  */
 227 const char *fdt_string(const void *fdt, int stroffset);
 228
 229 /**
 230  * fdt_num_mem_rsv - retreive the number of memory reserve map entries
 231  * @fdt: pointer to the device tree blob
 232  *
 233  * Returns the number of entries in the device tree blob's memory
 234  * reservation map.  This does not include the terminating 0,0 entry
 235  * or any other (0,0) entries reserved for expansion.
 236  *
 237  * returns:
 238  *     the number of entries
 239  */
 240 int fdt_num_mem_rsv(const void *fdt);
 241
 242 /**
 243  * fdt_get_mem_rsv - retreive one memory reserve map entry
 244  * @fdt: pointer to the device tree blob
 245  * @address, @size: pointers to 64-bit variables
 246  *
 247  * On success, *address and *size will contain the address and size of
 248  * the n-th reserve map entry from the device tree blob, in
 249  * native-endian format.
 250  *
 251  * returns:
 252  *     0, on success
 253  *     -FDT_ERR_BADMAGIC,
 254  *     -FDT_ERR_BADVERSION,
 255  *     -FDT_ERR_BADSTATE, standard meanings
 256  */
 257 int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
 258
 259 /**
 260  * fdt_subnode_offset_namelen - find a subnode based on substring
 261  * @fdt: pointer to the device tree blob
 262  * @parentoffset: structure block offset of a node
 263  * @name: name of the subnode to locate
 264  * @namelen: number of characters of name to consider
 265  *
 266  * Identical to fdt_subnode_offset(), but only examine the first
 267  * namelen characters of name for matching the subnode name.  This is
 268  * useful for finding subnodes based on a portion of a larger string,
 269  * such as a full path.
 270  */
 271 int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
 272                                const char *name, int namelen);
 273 /**
 274  * fdt_subnode_offset - find a subnode of a given node
 275  * @fdt: pointer to the device tree blob
 276  * @parentoffset: structure block offset of a node
 277  * @name: name of the subnode to locate
 278  *
 279  * fdt_subnode_offset() finds a subnode of the node at structure block
 280  * offset parentoffset with the given name.  name may include a unit
 281  * address, in which case fdt_subnode_offset() will find the subnode
 282  * with that unit address, or the unit address may be omitted, in
 283  * which case fdt_subnode_offset() will find an arbitrary subnode
 284  * whose name excluding unit address matches the given name.
 285  *
 286  * returns:
 287  *      structure block offset of the requested subnode (>=0), on success
 288  *      -FDT_ERR_NOTFOUND, if the requested subnode does not exist
 289  *      -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
 290  *      -FDT_ERR_BADMAGIC,
 291  *      -FDT_ERR_BADVERSION,
 292  *      -FDT_ERR_BADSTATE,
 293  *      -FDT_ERR_BADSTRUCTURE,
 294  *      -FDT_ERR_TRUNCATED, standard meanings.
 295  */
 296 int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
 297
 298 /**
 299  * fdt_path_offset - find a tree node by its full path
 300  * @fdt: pointer to the device tree blob
 301  * @path: full path of the node to locate
 302  *
 303  * fdt_path_offset() finds a node of a given path in the device tree.
 304  * Each path component may omit the unit address portion, but the
 305  * results of this are undefined if any such path component is
 306  * ambiguous (that is if there are multiple nodes at the relevant
 307  * level matching the given component, differentiated only by unit
 308  * address).
 309  *
 310  * returns:
 311  *      structure block offset of the node with the requested path (>=0), on success
 312  *      -FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
 313  *      -FDT_ERR_NOTFOUND, if the requested node does not exist
 314  *      -FDT_ERR_BADMAGIC,
 315  *      -FDT_ERR_BADVERSION,
 316  *      -FDT_ERR_BADSTATE,
 317  *      -FDT_ERR_BADSTRUCTURE,
 318  *      -FDT_ERR_TRUNCATED, standard meanings.
 319  */
 320 int fdt_path_offset(const void *fdt, const char *path);
 321
 322 /**
 323  * fdt_get_name - retreive the name of a given node
 324  * @fdt: pointer to the device tree blob
 325  * @nodeoffset: structure block offset of the starting node
 326  * @lenp: pointer to an integer variable (will be overwritten) or NULL
 327  *
 328  * fdt_get_name() retrieves the name (including unit address) of the
 329  * device tree node at structure block offset nodeoffset.  If lenp is
 330  * non-NULL, the length of this name is also returned, in the integer
 331  * pointed to by lenp.
 332  *
 333  * returns:
 334  *      pointer to the node's name, on success
 335  *              If lenp is non-NULL, *lenp contains the length of that name (>=0)
 336  *      NULL, on error
 337  *              if lenp is non-NULL *lenp contains an error code (<0):
 338  *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 339  *              -FDT_ERR_BADMAGIC,
 340  *              -FDT_ERR_BADVERSION,
 341  *              -FDT_ERR_BADSTATE, standard meanings
 342  */
 343 const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
 344
 345 /**
 346  * fdt_get_property - find a given property in a given node
 347  * @fdt: pointer to the device tree blob
 348  * @nodeoffset: offset of the node whose property to find
 349  * @name: name of the property to find
 350  * @lenp: pointer to an integer variable (will be overwritten) or NULL
 351  *
 352  * fdt_get_property() retrieves a pointer to the fdt_property
 353  * structure within the device tree blob corresponding to the property
 354  * named 'name' of the node at offset nodeoffset.  If lenp is
 355  * non-NULL, the length of the property value also returned, in the
 356  * integer pointed to by lenp.
 357  *
 358  * returns:
 359  *      pointer to the structure representing the property
 360  *              if lenp is non-NULL, *lenp contains the length of the property
 361  *              value (>=0)
 362  *      NULL, on error
 363  *              if lenp is non-NULL, *lenp contains an error code (<0):
 364  *              -FDT_ERR_NOTFOUND, node does not have named property
 365  *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 366  *              -FDT_ERR_BADMAGIC,
 367  *              -FDT_ERR_BADVERSION,
 368  *              -FDT_ERR_BADSTATE,
 369  *              -FDT_ERR_BADSTRUCTURE,
 370  *              -FDT_ERR_TRUNCATED, standard meanings
 371  */
 372 const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
 373                                             const char *name, int *lenp);
 374 static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
 375                                                       const char *name,
 376                                                       int *lenp)
 377 {
 378         return (struct fdt_property *)fdt_get_property(fdt, nodeoffset,
 379                                                        name, lenp);
 380 }
 381
 382 /**
 383  * fdt_getprop - retrieve the value of a given property
 384  * @fdt: pointer to the device tree blob
 385  * @nodeoffset: offset of the node whose property to find
 386  * @name: name of the property to find
 387  * @lenp: pointer to an integer variable (will be overwritten) or NULL
 388  *
 389  * fdt_getprop() retrieves a pointer to the value of the property
 390  * named 'name' of the node at offset nodeoffset (this will be a
 391  * pointer to within the device blob itself, not a copy of the value).
 392  * If lenp is non-NULL, the length of the property value also
 393  * returned, in the integer pointed to by lenp.
 394  *
 395  * returns:
 396  *      pointer to the property's value
 397  *              if lenp is non-NULL, *lenp contains the length of the property
 398  *              value (>=0)
 399  *      NULL, on error
 400  *              if lenp is non-NULL, *lenp contains an error code (<0):
 401  *              -FDT_ERR_NOTFOUND, node does not have named property
 402  *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 403  *              -FDT_ERR_BADMAGIC,
 404  *              -FDT_ERR_BADVERSION,
 405  *              -FDT_ERR_BADSTATE,
 406  *              -FDT_ERR_BADSTRUCTURE,
 407  *              -FDT_ERR_TRUNCATED, standard meanings
 408  */
 409 const void *fdt_getprop(const void *fdt, int nodeoffset,
 410                         const char *name, int *lenp);
 411 static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
 412                                   const char *name, int *lenp)
 413 {
 414         return (void *)fdt_getprop(fdt, nodeoffset, name, lenp);
 415 }
 416
 417 /**
 418  * fdt_get_phandle - retreive the phandle of a given node
 419  * @fdt: pointer to the device tree blob
 420  * @nodeoffset: structure block offset of the node
 421  *
 422  * fdt_get_phandle() retrieves the phandle of the device tree node at
 423  * structure block offset nodeoffset.
 424  *
 425  * returns:
 426  *      the phandle of the node at nodeoffset, on succes (!= 0, != -1)
 427  *      0, if the node has no phandle, or another error occurs
 428  */
 429 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
 430
 431 /**
 432  * fdt_get_path - determine the full path of a node
 433  * @fdt: pointer to the device tree blob
 434  * @nodeoffset: offset of the node whose path to find
 435  * @buf: character buffer to contain the returned path (will be overwritten)
 436  * @buflen: size of the character buffer at buf
 437  *
 438  * fdt_get_path() computes the full path of the node at offset
 439  * nodeoffset, and records that path in the buffer at buf.
 440  *
 441  * NOTE: This function is expensive, as it must scan the device tree
 442  * structure from the start to nodeoffset.
 443  *
 444  * returns:
 445  *      0, on success
 446  *              buf contains the absolute path of the node at
 447  *              nodeoffset, as a NUL-terminated string.
 448  *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 449  *      -FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
 450  *              characters and will not fit in the given buffer.
 451  *      -FDT_ERR_BADMAGIC,
 452  *      -FDT_ERR_BADVERSION,
 453  *      -FDT_ERR_BADSTATE,
 454  *      -FDT_ERR_BADSTRUCTURE, standard meanings
 455  */
 456 int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
 457
 458 /**
 459  * fdt_supernode_atdepth_offset - find a specific ancestor of a node
 460  * @fdt: pointer to the device tree blob
 461  * @nodeoffset: offset of the node whose parent to find
 462  * @supernodedepth: depth of the ancestor to find
 463  * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
 464  *
 465  * fdt_supernode_atdepth_offset() finds an ancestor of the given node
 466  * at a specific depth from the root (where the root itself has depth
 467  * 0, its immediate subnodes depth 1 and so forth).  So
 468  *      fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
 469  * will always return 0, the offset of the root node.  If the node at
 470  * nodeoffset has depth D, then:
 471  *      fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
 472  * will return nodeoffset itself.
 473  *
 474  * NOTE: This function is expensive, as it must scan the device tree
 475  * structure from the start to nodeoffset.
 476  *
 477  * returns:
 478
 479  *      structure block offset of the node at node offset's ancestor
 480  *              of depth supernodedepth (>=0), on success
 481  *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 482 *       -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of nodeoffset
 483  *      -FDT_ERR_BADMAGIC,
 484  *      -FDT_ERR_BADVERSION,
 485  *      -FDT_ERR_BADSTATE,
 486  *      -FDT_ERR_BADSTRUCTURE, standard meanings
 487  */
 488 int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
 489                                  int supernodedepth, int *nodedepth);
 490
 491 /**
 492  * fdt_node_depth - find the depth of a given node
 493  * @fdt: pointer to the device tree blob
 494  * @nodeoffset: offset of the node whose parent to find
 495  *
 496  * fdt_node_depth() finds the depth of a given node.  The root node
 497  * has depth 0, its immediate subnodes depth 1 and so forth.
 498  *
 499  * NOTE: This function is expensive, as it must scan the device tree
 500  * structure from the start to nodeoffset.
 501  *
 502  * returns:
 503  *      depth of the node at nodeoffset (>=0), on success
 504  *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 505  *      -FDT_ERR_BADMAGIC,
 506  *      -FDT_ERR_BADVERSION,
 507  *      -FDT_ERR_BADSTATE,
 508  *      -FDT_ERR_BADSTRUCTURE, standard meanings
 509  */
 510 int fdt_node_depth(const void *fdt, int nodeoffset);
 511
 512 /**
 513  * fdt_parent_offset - find the parent of a given node
 514  * @fdt: pointer to the device tree blob
 515  * @nodeoffset: offset of the node whose parent to find
 516  *
 517  * fdt_parent_offset() locates the parent node of a given node (that
 518  * is, it finds the offset of the node which contains the node at
 519  * nodeoffset as a subnode).
 520  *
 521  * NOTE: This function is expensive, as it must scan the device tree
 522  * structure from the start to nodeoffset, *twice*.
 523  *
 524  * returns:
 525  *      stucture block offset of the parent of the node at nodeoffset
 526  *              (>=0), on success
 527  *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 528  *      -FDT_ERR_BADMAGIC,
 529  *      -FDT_ERR_BADVERSION,
 530  *      -FDT_ERR_BADSTATE,
 531  *      -FDT_ERR_BADSTRUCTURE, standard meanings
 532  */
 533 int fdt_parent_offset(const void *fdt, int nodeoffset);
 534
 535 /**
 536  * fdt_node_offset_by_prop_value - find nodes with a given property value
 537  * @fdt: pointer to the device tree blob
 538  * @startoffset: only find nodes after this offset
 539  * @propname: property name to check
 540  * @propval: property value to search for
 541  * @proplen: length of the value in propval
 542  *
 543  * fdt_node_offset_by_prop_value() returns the offset of the first
 544  * node after startoffset, which has a property named propname whose
 545  * value is of length proplen and has value equal to propval; or if
 546  * startoffset is -1, the very first such node in the tree.
 547  *
 548  * To iterate through all nodes matching the criterion, the following
 549  * idiom can be used:
 550  *      offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
 551  *                                             propval, proplen);
 552  *      while (offset != -FDT_ERR_NOTFOUND) {
 553  *              ... other code here ...
 554  *              offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
 555  *                                                     propval, proplen);
 556  *      }
 557  *
 558  * Note the -1 in the first call to the function, if 0 is used here
 559  * instead, the function will never locate the root node, even if it
 560  * matches the criterion.
 561  *
 562  * returns:
 563  *      structure block offset of the located node (>= 0, >startoffset),
 564  *               on success
 565  *      -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 566  *              tree after startoffset
 567  *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 568  *      -FDT_ERR_BADMAGIC,
 569  *      -FDT_ERR_BADVERSION,
 570  *      -FDT_ERR_BADSTATE,
 571  *      -FDT_ERR_BADSTRUCTURE, standard meanings
 572  */
 573 int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
 574                                   const char *propname,
 575                                   const void *propval, int proplen);
 576
 577 /**
 578  * fdt_node_offset_by_phandle - find the node with a given phandle
 579  * @fdt: pointer to the device tree blob
 580  * @phandle: phandle value
 581  *
 582  * fdt_node_offset_by_prop_value() returns the offset of the node
 583  * which has the given phandle value.  If there is more than one node
 584  * in the tree with the given phandle (an invalid tree), results are
 585  * undefined.
 586  *
 587  * returns:
 588  *      structure block offset of the located node (>= 0), on success
 589  *      -FDT_ERR_NOTFOUND, no node with that phandle exists
 590  *      -FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
 591  *      -FDT_ERR_BADMAGIC,
 592  *      -FDT_ERR_BADVERSION,
 593  *      -FDT_ERR_BADSTATE,
 594  *      -FDT_ERR_BADSTRUCTURE, standard meanings
 595  */
 596 int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
 597
 598 /**
 599  * fdt_node_check_compatible: check a node's compatible property
 600  * @fdt: pointer to the device tree blob
 601  * @nodeoffset: offset of a tree node
 602  * @compatible: string to match against
 603  *
 604  *
 605  * fdt_node_check_compatible() returns 0 if the given node contains a
 606  * 'compatible' property with the given string as one of its elements,
 607  * it returns non-zero otherwise, or on error.
 608  *
 609  * returns:
 610  *      0, if the node has a 'compatible' property listing the given string
 611  *      1, if the node has a 'compatible' property, but it does not list
 612  *              the given string
 613  *      -FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
 614  *      -FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
 615  *      -FDT_ERR_BADMAGIC,
 616  *      -FDT_ERR_BADVERSION,
 617  *      -FDT_ERR_BADSTATE,
 618  *      -FDT_ERR_BADSTRUCTURE, standard meanings
 619  */
 620 int fdt_node_check_compatible(const void *fdt, int nodeoffset,
 621                               const char *compatible);
 622
 623 /**
 624  * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
 625  * @fdt: pointer to the device tree blob
 626  * @startoffset: only find nodes after this offset
 627  * @compatible: 'compatible' string to match against
 628  *
 629  * fdt_node_offset_by_compatible() returns the offset of the first
 630  * node after startoffset, which has a 'compatible' property which
 631  * lists the given compatible string; or if startoffset is -1, the
 632  * very first such node in the tree.
 633  *
 634  * To iterate through all nodes matching the criterion, the following
 635  * idiom can be used:
 636  *      offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
 637  *      while (offset != -FDT_ERR_NOTFOUND) {
 638  *              ... other code here ...
 639  *              offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
 640  *      }
 641  *
 642  * Note the -1 in the first call to the function, if 0 is used here
 643  * instead, the function will never locate the root node, even if it
 644  * matches the criterion.
 645  *
 646  * returns:
 647  *      structure block offset of the located node (>= 0, >startoffset),
 648  *               on success
 649  *      -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 650  *              tree after startoffset
 651  *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 652  *      -FDT_ERR_BADMAGIC,
 653  *      -FDT_ERR_BADVERSION,
 654  *      -FDT_ERR_BADSTATE,
 655  *      -FDT_ERR_BADSTRUCTURE, standard meanings
 656  */
 657 int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
 658                                   const char *compatible);
 659
 660 /**********************************************************************/
 661 /* Write-in-place functions                                           */
 662 /**********************************************************************/
 663
 664 /**
 665  * fdt_setprop_inplace - change a property's value, but not its size
 666  * @fdt: pointer to the device tree blob
 667  * @nodeoffset: offset of the node whose property to change
 668  * @name: name of the property to change
 669  * @val: pointer to data to replace the property value with
 670  * @len: length of the property value
 671  *
 672  * fdt_setprop_inplace() replaces the value of a given property with
 673  * the data in val, of length len.  This function cannot change the
 674  * size of a property, and so will only work if len is equal to the
 675  * current length of the property.
 676  *
 677  * This function will alter only the bytes in the blob which contain
 678  * the given property value, and will not alter or move any other part
 679  * of the tree.
 680  *
 681  * returns:
 682  *      0, on success
 683  *      -FDT_ERR_NOSPACE, if len is not equal to the property's current length
 684  *      -FDT_ERR_NOTFOUND, node does not have the named property
 685  *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 686  *      -FDT_ERR_BADMAGIC,
 687  *      -FDT_ERR_BADVERSION,
 688  *      -FDT_ERR_BADSTATE,
 689  *      -FDT_ERR_BADSTRUCTURE,
 690  *      -FDT_ERR_TRUNCATED, standard meanings
 691  */
 692 int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
 693                         const void *val, int len);
 694
 695 /**
 696  * fdt_setprop_inplace_cell - change the value of a single-cell property
 697  * @fdt: pointer to the device tree blob
 698  * @nodeoffset: offset of the node whose property to change
 699  * @name: name of the property to change
 700  * @val: cell (32-bit integer) value to replace the property with
 701  *
 702  * fdt_setprop_inplace_cell() replaces the value of a given property
 703  * with the 32-bit integer cell value in val, converting val to
 704  * big-endian if necessary.  This function cannot change the size of a
 705  * property, and so will only work if the property already exists and
 706  * has length 4.
 707  *
 708  * This function will alter only the bytes in the blob which contain
 709  * the given property value, and will not alter or move any other part
 710  * of the tree.
 711  *
 712  * returns:
 713  *      0, on success
 714  *      -FDT_ERR_NOSPACE, if the property's length is not equal to 4
 715   *     -FDT_ERR_NOTFOUND, node does not have the named property
 716  *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 717  *      -FDT_ERR_BADMAGIC,
 718  *      -FDT_ERR_BADVERSION,
 719  *      -FDT_ERR_BADSTATE,
 720  *      -FDT_ERR_BADSTRUCTURE,
 721  *      -FDT_ERR_TRUNCATED, standard meanings
 722  */
 723 static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
 724                                            const char *name, uint32_t val)
 725 {
 726         val = cpu_to_fdt32(val);
 727         return fdt_setprop_inplace(fdt, nodeoffset, name, &val, sizeof(val));
 728 }
 729
 730 /**
 731  * fdt_nop_property - replace a property with nop tags
 732  * @fdt: pointer to the device tree blob
 733  * @nodeoffset: offset of the node whose property to nop
 734  * @name: name of the property to nop
 735  *
 736  * fdt_nop_property() will replace a given property's representation
 737  * in the blob with FDT_NOP tags, effectively removing it from the
 738  * tree.
 739  *
 740  * This function will alter only the bytes in the blob which contain
 741  * the property, and will not alter or move any other part of the
 742  * tree.
 743  *
 744  * returns:
 745  *      0, on success
 746  *      -FDT_ERR_NOTFOUND, node does not have the named property
 747  *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 748  *      -FDT_ERR_BADMAGIC,
 749  *      -FDT_ERR_BADVERSION,
 750  *      -FDT_ERR_BADSTATE,
 751  *      -FDT_ERR_BADSTRUCTURE,
 752  *      -FDT_ERR_TRUNCATED, standard meanings
 753  */
 754 int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
 755
 756 /**
 757  * fdt_nop_node - replace a node (subtree) with nop tags
 758  * @fdt: pointer to the device tree blob
 759  * @nodeoffset: offset of the node to nop
 760  *
 761  * fdt_nop_node() will replace a given node's representation in the
 762  * blob, including all its subnodes, if any, with FDT_NOP tags,
 763  * effectively removing it from the tree.
 764  *
 765  * This function will alter only the bytes in the blob which contain
 766  * the node and its properties and subnodes, and will not alter or
 767  * move any other part of the tree.
 768  *
 769  * returns:
 770  *      0, on success
 771  *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 772  *      -FDT_ERR_BADMAGIC,
 773  *      -FDT_ERR_BADVERSION,
 774  *      -FDT_ERR_BADSTATE,
 775  *      -FDT_ERR_BADSTRUCTURE,
 776  *      -FDT_ERR_TRUNCATED, standard meanings
 777  */
 778 int fdt_nop_node(void *fdt, int nodeoffset);
 779
 780 /**********************************************************************/
 781 /* Sequential write functions                                         */
 782 /**********************************************************************/
 783
 784 int fdt_create(void *buf, int bufsize);
 785 int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
 786 int fdt_finish_reservemap(void *fdt);
 787 int fdt_begin_node(void *fdt, const char *name);
 788 int fdt_property(void *fdt, const char *name, const void *val, int len);
 789 static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
 790 {
 791         val = cpu_to_fdt32(val);
 792         return fdt_property(fdt, name, &val, sizeof(val));
 793 }
 794 #define fdt_property_string(fdt, name, str) \
 795         fdt_property(fdt, name, str, strlen(str)+1)
 796 int fdt_end_node(void *fdt);
 797 int fdt_finish(void *fdt);
 798
 799 /**********************************************************************/
 800 /* Read-write functions                                               */
 801 /**********************************************************************/
 802
 803 int fdt_open_into(const void *fdt, void *buf, int bufsize);
 804 int fdt_pack(void *fdt);
 805
 806 /**
 807  * fdt_add_mem_rsv - add one memory reserve map entry
 808  * @fdt: pointer to the device tree blob
 809  * @addres, @size: 64-bit values (native endian)
 810  *
 811  * Adds a reserve map entry to the given blob reserving a region at
 812  * address address of length size.
 813  *
 814  * This function will insert data into the reserve map and will
 815  * therfore change the indexes of some entries in the table.
 816  *
 817  * returns:
 818  *      0, on success
 819  *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 820  *              contain the new reservation entry
 821  *      -FDT_ERR_BADMAGIC,
 822  *      -FDT_ERR_BADVERSION,
 823  *      -FDT_ERR_BADSTATE,
 824  *      -FDT_ERR_BADSTRUCTURE,
 825  *      -FDT_ERR_BADLAYOUT,
 826  *      -FDT_ERR_TRUNCATED, standard meanings
 827  */
 828 int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
 829
 830 /**
 831  * fdt_del_mem_rsv - remove a memory reserve map entry
 832  * @fdt: pointer to the device tree blob
 833  * @n: entry to remove
 834  *
 835  * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
 836  * the blob.
 837  *
 838  * This function will delete data from the reservation table and will
 839  * therfore change the indexes of some entries in the table.
 840  *
 841  * returns:
 842  *      0, on success
 843  *      -FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
 844  *              are less than n+1 reserve map entries)
 845  *      -FDT_ERR_BADMAGIC,
 846  *      -FDT_ERR_BADVERSION,
 847  *      -FDT_ERR_BADSTATE,
 848  *      -FDT_ERR_BADSTRUCTURE,
 849  *      -FDT_ERR_BADLAYOUT,
 850  *      -FDT_ERR_TRUNCATED, standard meanings
 851  */
 852 int fdt_del_mem_rsv(void *fdt, int n);
 853
 854 /**
 855  * fdt_set_name - change the name of a given node
 856  * @fdt: pointer to the device tree blob
 857  * @nodeoffset: structure block offset of a node
 858  * @name: name to give the node
 859  *
 860  * fdt_set_name() replaces the name (including unit address, if any)
 861  * of the given node with the given string.  NOTE: this function can't
 862  * efficiently check if the new name is unique amongst the given
 863  * node's siblings; results are undefined if this function is invoked
 864  * with a name equal to one of the given node's siblings.
 865  *
 866  * This function may insert or delete data from the blob, and will
 867  * therefore change the offsets of some existing nodes.
 868  *
 869  * returns:
 870  *      0, on success
 871  *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob
 872  *              to contain the new name
 873  *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 874  *      -FDT_ERR_BADMAGIC,
 875  *      -FDT_ERR_BADVERSION,
 876  *      -FDT_ERR_BADSTATE, standard meanings
 877  */
 878 int fdt_set_name(void *fdt, int nodeoffset, const char *name);
 879
 880 /**
 881  * fdt_setprop - create or change a property
 882  * @fdt: pointer to the device tree blob
 883  * @nodeoffset: offset of the node whose property to change
 884  * @name: name of the property to change
 885  * @val: pointer to data to set the property value to
 886  * @len: length of the property value
 887  *
 888  * fdt_setprop() sets the value of the named property in the given
 889  * node to the given value and length, creeating the property if it
 890  * does not already exist.
 891  *
 892  * This function may insert or delete data from the blob, and will
 893  * therefore change the offsets of some existing nodes.
 894  *
 895  * returns:
 896  *      0, on success
 897  *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 898  *              contain the new property value
 899  *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 900  *      -FDT_ERR_BADLAYOUT,
 901  *      -FDT_ERR_BADMAGIC,
 902  *      -FDT_ERR_BADVERSION,
 903  *      -FDT_ERR_BADSTATE,
 904  *      -FDT_ERR_BADSTRUCTURE,
 905  *      -FDT_ERR_BADLAYOUT,
 906  *      -FDT_ERR_TRUNCATED, standard meanings
 907  */
 908 int fdt_setprop(void *fdt, int nodeoffset, const char *name,
 909                 const void *val, int len);
 910
 911 /**
 912  * fdt_setprop_cell - set a property to a single cell value
 913  * @fdt: pointer to the device tree blob
 914  * @nodeoffset: offset of the node whose property to change
 915  * @name: name of the property to change
 916  * @val: 32-bit integer value for the property (native endian)
 917  *
 918  * fdt_setprop_cell() sets the value of the named property in the
 919  * given node to the given cell value (converting to big-endian if
 920  * necessary), or creates a new property with that value if it does
 921  * not already exist.
 922  *
 923  * This function may insert or delete data from the blob, and will
 924  * therefore change the offsets of some existing nodes.
 925  *
 926  * returns:
 927  *      0, on success
 928  *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 929  *              contain the new property value
 930  *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 931  *      -FDT_ERR_BADLAYOUT,
 932  *      -FDT_ERR_BADMAGIC,
 933  *      -FDT_ERR_BADVERSION,
 934  *      -FDT_ERR_BADSTATE,
 935  *      -FDT_ERR_BADSTRUCTURE,
 936  *      -FDT_ERR_BADLAYOUT,
 937  *      -FDT_ERR_TRUNCATED, standard meanings
 938  */
 939 static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
 940                                    uint32_t val)
 941 {
 942         val = cpu_to_fdt32(val);
 943         return fdt_setprop(fdt, nodeoffset, name, &val, sizeof(val));
 944 }
 945
 946 /**
 947  * fdt_setprop_string - set a property to a string value
 948  * @fdt: pointer to the device tree blob
 949  * @nodeoffset: offset of the node whose property to change
 950  * @name: name of the property to change
 951  * @str: string value for the property
 952  *
 953  * fdt_setprop_string() sets the value of the named property in the
 954  * given node to the given string value (using the length of the
 955  * string to determine the new length of the property), or creates a
 956  * new property with that value if it does not already exist.
 957  *
 958  * This function may insert or delete data from the blob, and will
 959  * therefore change the offsets of some existing nodes.
 960  *
 961  * returns:
 962  *      0, on success
 963  *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 964  *              contain the new property value
 965  *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 966  *      -FDT_ERR_BADLAYOUT,
 967  *      -FDT_ERR_BADMAGIC,
 968  *      -FDT_ERR_BADVERSION,
 969  *      -FDT_ERR_BADSTATE,
 970  *      -FDT_ERR_BADSTRUCTURE,
 971  *      -FDT_ERR_BADLAYOUT,
 972  *      -FDT_ERR_TRUNCATED, standard meanings
 973  */
 974 #define fdt_setprop_string(fdt, nodeoffset, name, str) \
 975         fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
 976
 977 /**
 978  * fdt_delprop - delete a property
 979  * @fdt: pointer to the device tree blob
 980  * @nodeoffset: offset of the node whose property to nop
 981  * @name: name of the property to nop
 982  *
 983  * fdt_del_property() will delete the given property.
 984  *
 985  * This function will delete data from the blob, and will therefore
 986  * change the offsets of some existing nodes.
 987  *
 988  * returns:
 989  *      0, on success
 990  *      -FDT_ERR_NOTFOUND, node does not have the named property
 991  *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 992  *      -FDT_ERR_BADLAYOUT,
 993  *      -FDT_ERR_BADMAGIC,
 994  *      -FDT_ERR_BADVERSION,
 995  *      -FDT_ERR_BADSTATE,
 996  *      -FDT_ERR_BADSTRUCTURE,
 997  *      -FDT_ERR_TRUNCATED, standard meanings
 998  */
 999 int fdt_delprop(void *fdt, int nodeoffset, const char *name);
1000
1001 /**
1002  * fdt_add_subnode_namelen - creates a new node based on substring
1003  * @fdt: pointer to the device tree blob
1004  * @parentoffset: structure block offset of a node
1005  * @name: name of the subnode to locate
1006  * @namelen: number of characters of name to consider
1007  *
1008  * Identical to fdt_add_subnode(), but use only the first namelen
1009  * characters of name as the name of the new node.  This is useful for
1010  * creating subnodes based on a portion of a larger string, such as a
1011  * full path.
1012  */
1013 int fdt_add_subnode_namelen(void *fdt, int parentoffset,
1014                             const char *name, int namelen);
1015
1016 /**
1017  * fdt_add_subnode - creates a new node
1018  * @fdt: pointer to the device tree blob
1019  * @parentoffset: structure block offset of a node
1020  * @name: name of the subnode to locate
1021  *
1022  * fdt_add_subnode() creates a new node as a subnode of the node at
1023  * structure block offset parentoffset, with the given name (which
1024  * should include the unit address, if any).
1025  *
1026  * This function will insert data into the blob, and will therefore
1027  * change the offsets of some existing nodes.
1028
1029  * returns:
1030  *      structure block offset of the created nodeequested subnode (>=0), on success
1031  *      -FDT_ERR_NOTFOUND, if the requested subnode does not exist
1032  *      -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
1033  *      -FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
1034  *              the given name
1035  *      -FDT_ERR_NOSPACE, if there is insufficient free space in the
1036  *              blob to contain the new node
1037  *      -FDT_ERR_NOSPACE
1038  *      -FDT_ERR_BADLAYOUT
1039  *      -FDT_ERR_BADMAGIC,
1040  *      -FDT_ERR_BADVERSION,
1041  *      -FDT_ERR_BADSTATE,
1042  *      -FDT_ERR_BADSTRUCTURE,
1043  *      -FDT_ERR_TRUNCATED, standard meanings.
1044  */
1045 int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
1046
1047 /**
1048  * fdt_del_node - delete a node (subtree)
1049  * @fdt: pointer to the device tree blob
1050  * @nodeoffset: offset of the node to nop
1051  *
1052  * fdt_del_node() will remove the given node, including all its
1053  * subnodes if any, from the blob.
1054  *
1055  * This function will delete data from the blob, and will therefore
1056  * change the offsets of some existing nodes.
1057  *
1058  * returns:
1059  *      0, on success
1060  *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1061  *      -FDT_ERR_BADLAYOUT,
1062  *      -FDT_ERR_BADMAGIC,
1063  *      -FDT_ERR_BADVERSION,
1064  *      -FDT_ERR_BADSTATE,
1065  *      -FDT_ERR_BADSTRUCTURE,
1066  *      -FDT_ERR_TRUNCATED, standard meanings
1067  */
1068 int fdt_del_node(void *fdt, int nodeoffset);
1069
1070 /**********************************************************************/
1071 /* Debugging / informational functions                                */
1072 /**********************************************************************/
1073
1074 const char *fdt_strerror(int errval);
1075
1076 #endif /* _LIBFDT_H */