- * libfdt - Flat Device Tree manipulation
- * Copyright (C) 2006 David Gibson, IBM Corporation.
- *
- * libfdt is dual licensed: you can use it either under the terms of
- * the GPL, or the BSD license, at your option.
- *
- * a) This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public
- * License along with this library; if not, write to the Free
- * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
- * MA 02110-1301 USA
- *
- * Alternatively,
- *
- * b) Redistribution and use in source and binary forms, with or
- * without modification, are permitted provided that the following
- * conditions are met:
- *
- * 1. Redistributions of source code must retain the above
- * copyright notice, this list of conditions and the following
- * disclaimer.
- * 2. Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following
- * disclaimer in the documentation and/or other materials
- * provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
- * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <libfdt_env.h>
-#include <fdt.h>
-
-#define FDT_FIRST_SUPPORTED_VERSION 0x10
-#define FDT_LAST_SUPPORTED_VERSION 0x11
-
-/* Error codes: informative error codes */
-#define FDT_ERR_NOTFOUND 1
- /* FDT_ERR_NOTFOUND: The requested node or property does not exist */
-#define FDT_ERR_EXISTS 2
- /* FDT_ERR_EXISTS: Attemped to create a node or property which
- * already exists */
-#define FDT_ERR_NOSPACE 3
- /* FDT_ERR_NOSPACE: Operation needed to expand the device
- * tree, but its buffer did not have sufficient space to
- * contain the expanded tree. Use fdt_open_into() to move the
- * device tree to a buffer with more space. */
-
-/* Error codes: codes for bad parameters */
-#define FDT_ERR_BADOFFSET 4
- /* FDT_ERR_BADOFFSET: Function was passed a structure block
- * offset which is out-of-bounds, or which points to an
- * unsuitable part of the structure for the operation. */
-#define FDT_ERR_BADPATH 5
- /* FDT_ERR_BADPATH: Function was passed a badly formatted path
- * (e.g. missing a leading / for a function which requires an
- * absolute path) */
-#define FDT_ERR_BADPHANDLE 6
- /* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle
- * value. phandle values of 0 and -1 are not permitted. */
-#define FDT_ERR_BADSTATE 7
- /* FDT_ERR_BADSTATE: Function was passed an incomplete device
- * tree created by the sequential-write functions, which is
- * not sufficiently complete for the requested operation. */
-
-/* Error codes: codes for bad device tree blobs */
-#define FDT_ERR_TRUNCATED 8
- /* FDT_ERR_TRUNCATED: Structure block of the given device tree
- * ends without an FDT_END tag. */
-#define FDT_ERR_BADMAGIC 9
- /* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
- * device tree at all - it is missing the flattened device
- * tree magic number. */
-#define FDT_ERR_BADVERSION 10
- /* FDT_ERR_BADVERSION: Given device tree has a version which
- * can't be handled by the requested operation. For
- * read-write functions, this may mean that fdt_open_into() is
- * required to convert the tree to the expected version. */
-#define FDT_ERR_BADSTRUCTURE 11
- /* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
- * structure block or other serious error (e.g. misnested
- * nodes, or subnodes preceding properties). */
-#define FDT_ERR_BADLAYOUT 12
- /* FDT_ERR_BADLAYOUT: For read-write functions, the given
- * device tree has it's sub-blocks in an order that the
- * function can't handle (memory reserve map, then structure,
- * then strings). Use fdt_open_into() to reorganize the tree
- * into a form suitable for the read-write operations. */
-
-/* "Can't happen" error indicating a bug in libfdt */
-#define FDT_ERR_INTERNAL 13
- /* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
- * Should never be returned, if it is, it indicates a bug in
- * libfdt itself. */
-
-#define FDT_ERR_MAX 13
-
-/**********************************************************************/
-/* Low-level functions (you probably don't need these) */
-/**********************************************************************/
-
-const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
-static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
-{
- return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
-}
-
-uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
-
-/**********************************************************************/
-/* Traversal functions */
-/**********************************************************************/
-
-int fdt_next_node(const void *fdt, int offset, int *depth);
-
-/**********************************************************************/
-/* General functions */
-/**********************************************************************/
-
-#define fdt_get_header(fdt, field) \
- (fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
-#define fdt_magic(fdt) (fdt_get_header(fdt, magic))
-#define fdt_totalsize(fdt) (fdt_get_header(fdt, totalsize))
-#define fdt_off_dt_struct(fdt) (fdt_get_header(fdt, off_dt_struct))
-#define fdt_off_dt_strings(fdt) (fdt_get_header(fdt, off_dt_strings))
-#define fdt_off_mem_rsvmap(fdt) (fdt_get_header(fdt, off_mem_rsvmap))
-#define fdt_version(fdt) (fdt_get_header(fdt, version))
-#define fdt_last_comp_version(fdt) (fdt_get_header(fdt, last_comp_version))
-#define fdt_boot_cpuid_phys(fdt) (fdt_get_header(fdt, boot_cpuid_phys))
-#define fdt_size_dt_strings(fdt) (fdt_get_header(fdt, size_dt_strings))
-#define fdt_size_dt_struct(fdt) (fdt_get_header(fdt, size_dt_struct))
-
-#define __fdt_set_hdr(name) \
- static inline void fdt_set_##name(void *fdt, uint32_t val) \
- { \
- struct fdt_header *fdth = (struct fdt_header*)fdt; \
- fdth->name = cpu_to_fdt32(val); \
- }
-__fdt_set_hdr(magic);
-__fdt_set_hdr(totalsize);
-__fdt_set_hdr(off_dt_struct);
-__fdt_set_hdr(off_dt_strings);
-__fdt_set_hdr(off_mem_rsvmap);
-__fdt_set_hdr(version);
-__fdt_set_hdr(last_comp_version);
-__fdt_set_hdr(boot_cpuid_phys);
-__fdt_set_hdr(size_dt_strings);
-__fdt_set_hdr(size_dt_struct);
-#undef __fdt_set_hdr
-
-/**
- * fdt_check_header - sanity check a device tree or possible device tree
- * @fdt: pointer to data which might be a flattened device tree
- *
- * fdt_check_header() checks that the given buffer contains what
- * appears to be a flattened device tree with sane information in its
- * header.
- *
- * returns:
- * 0, if the buffer appears to contain a valid device tree
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE, standard meanings, as above
- */
-int fdt_check_header(const void *fdt);
-
-/**
- * fdt_move - move a device tree around in memory
- * @fdt: pointer to the device tree to move
- * @buf: pointer to memory where the device is to be moved
- * @bufsize: size of the memory space at buf
- *
- * fdt_move() relocates, if possible, the device tree blob located at
- * fdt to the buffer at buf of size bufsize. The buffer may overlap
- * with the existing device tree blob at fdt. Therefore,
- * fdt_move(fdt, fdt, fdt_totalsize(fdt))
- * should always succeed.
- *
- * returns:
- * 0, on success
- * -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE, standard meanings
- */
-int fdt_move(const void *fdt, void *buf, int bufsize);
-
-/**********************************************************************/
-/* Read-only functions */
-/**********************************************************************/
-
-/**
- * fdt_string - retrieve a string from the strings block of a device tree
- * @fdt: pointer to the device tree blob
- * @stroffset: offset of the string within the strings block (native endian)
- *
- * fdt_string() retrieves a pointer to a single string from the
- * strings block of the device tree blob at fdt.
- *
- * returns:
- * a pointer to the string, on success
- * NULL, if stroffset is out of bounds
- */
-const char *fdt_string(const void *fdt, int stroffset);
-
-/**
- * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
- * @fdt: pointer to the device tree blob
- *
- * Returns the number of entries in the device tree blob's memory
- * reservation map. This does not include the terminating 0,0 entry
- * or any other (0,0) entries reserved for expansion.
- *
- * returns:
- * the number of entries
- */
-int fdt_num_mem_rsv(const void *fdt);
-
-/**
- * fdt_get_mem_rsv - retrieve one memory reserve map entry
- * @fdt: pointer to the device tree blob
- * @address, @size: pointers to 64-bit variables
- *
- * On success, *address and *size will contain the address and size of
- * the n-th reserve map entry from the device tree blob, in
- * native-endian format.
- *
- * returns:
- * 0, on success
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE, standard meanings
- */
-int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
-
-/**
- * fdt_subnode_offset_namelen - find a subnode based on substring
- * @fdt: pointer to the device tree blob
- * @parentoffset: structure block offset of a node
- * @name: name of the subnode to locate
- * @namelen: number of characters of name to consider
- *
- * Identical to fdt_subnode_offset(), but only examine the first
- * namelen characters of name for matching the subnode name. This is
- * useful for finding subnodes based on a portion of a larger string,
- * such as a full path.
- */
-int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
- const char *name, int namelen);
-/**
- * fdt_subnode_offset - find a subnode of a given node
- * @fdt: pointer to the device tree blob
- * @parentoffset: structure block offset of a node
- * @name: name of the subnode to locate
- *
- * fdt_subnode_offset() finds a subnode of the node at structure block
- * offset parentoffset with the given name. name may include a unit
- * address, in which case fdt_subnode_offset() will find the subnode
- * with that unit address, or the unit address may be omitted, in
- * which case fdt_subnode_offset() will find an arbitrary subnode
- * whose name excluding unit address matches the given name.
- *
- * returns:
- * structure block offset of the requested subnode (>=0), on success
- * -FDT_ERR_NOTFOUND, if the requested subnode does not exist
- * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE,
- * -FDT_ERR_BADSTRUCTURE,
- * -FDT_ERR_TRUNCATED, standard meanings.
- */
-int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
-
-/**
- * fdt_path_offset - find a tree node by its full path
- * @fdt: pointer to the device tree blob
- * @path: full path of the node to locate
- *
- * fdt_path_offset() finds a node of a given path in the device tree.
- * Each path component may omit the unit address portion, but the
- * results of this are undefined if any such path component is
- * ambiguous (that is if there are multiple nodes at the relevant
- * level matching the given component, differentiated only by unit
- * address).
- *
- * returns:
- * structure block offset of the node with the requested path (>=0), on success
- * -FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
- * -FDT_ERR_NOTFOUND, if the requested node does not exist
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE,
- * -FDT_ERR_BADSTRUCTURE,
- * -FDT_ERR_TRUNCATED, standard meanings.
- */
-int fdt_path_offset(const void *fdt, const char *path);
-
-/**
- * fdt_get_name - retrieve the name of a given node
- * @fdt: pointer to the device tree blob
- * @nodeoffset: structure block offset of the starting node
- * @lenp: pointer to an integer variable (will be overwritten) or NULL
- *
- * fdt_get_name() retrieves the name (including unit address) of the
- * device tree node at structure block offset nodeoffset. If lenp is
- * non-NULL, the length of this name is also returned, in the integer
- * pointed to by lenp.
- *
- * returns:
- * pointer to the node's name, on success
- * If lenp is non-NULL, *lenp contains the length of that name (>=0)
- * NULL, on error
- * if lenp is non-NULL *lenp contains an error code (<0):
- * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE, standard meanings
- */
-const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
-
-/**
- * fdt_first_property_offset - find the offset of a node's first property
- * @fdt: pointer to the device tree blob
- * @nodeoffset: structure block offset of a node
- *
- * fdt_first_property_offset() finds the first property of the node at
- * the given structure block offset.
- *
- * returns:
- * structure block offset of the property (>=0), on success
- * -FDT_ERR_NOTFOUND, if the requested node has no properties
- * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE,
- * -FDT_ERR_BADSTRUCTURE,
- * -FDT_ERR_TRUNCATED, standard meanings.
- */
-int fdt_first_property_offset(const void *fdt, int nodeoffset);
-
-/**
- * fdt_next_property_offset - step through a node's properties
- * @fdt: pointer to the device tree blob
- * @offset: structure block offset of a property
- *
- * fdt_next_property_offset() finds the property immediately after the
- * one at the given structure block offset. This will be a property
- * of the same node as the given property.
- *
- * returns:
- * structure block offset of the next property (>=0), on success
- * -FDT_ERR_NOTFOUND, if the given property is the last in its node
- * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE,
- * -FDT_ERR_BADSTRUCTURE,
- * -FDT_ERR_TRUNCATED, standard meanings.
- */
-int fdt_next_property_offset(const void *fdt, int offset);
-
-/**
- * fdt_get_property_by_offset - retrieve the property at a given offset
- * @fdt: pointer to the device tree blob
- * @offset: offset of the property to retrieve
- * @lenp: pointer to an integer variable (will be overwritten) or NULL
- *
- * fdt_get_property_by_offset() retrieves a pointer to the
- * fdt_property structure within the device tree blob at the given
- * offset. If lenp is non-NULL, the length of the property value is
- * also returned, in the integer pointed to by lenp.
- *
- * returns:
- * pointer to the structure representing the property
- * if lenp is non-NULL, *lenp contains the length of the property
- * value (>=0)
- * NULL, on error
- * if lenp is non-NULL, *lenp contains an error code (<0):
- * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE,
- * -FDT_ERR_BADSTRUCTURE,
- * -FDT_ERR_TRUNCATED, standard meanings
- */
-const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
- int offset,
- int *lenp);
-
-/**
- * fdt_get_property_namelen - find a property based on substring
- * @fdt: pointer to the device tree blob
- * @nodeoffset: offset of the node whose property to find
- * @name: name of the property to find
- * @namelen: number of characters of name to consider
- * @lenp: pointer to an integer variable (will be overwritten) or NULL
- *
- * Identical to fdt_get_property_namelen(), but only examine the first
- * namelen characters of name for matching the property name.
- */
-const struct fdt_property *fdt_get_property_namelen(const void *fdt,
- int nodeoffset,
- const char *name,
- int namelen, int *lenp);
-
-/**
- * fdt_get_property - find a given property in a given node
- * @fdt: pointer to the device tree blob
- * @nodeoffset: offset of the node whose property to find
- * @name: name of the property to find
- * @lenp: pointer to an integer variable (will be overwritten) or NULL
- *
- * fdt_get_property() retrieves a pointer to the fdt_property
- * structure within the device tree blob corresponding to the property
- * named 'name' of the node at offset nodeoffset. If lenp is
- * non-NULL, the length of the property value is also returned, in the
- * integer pointed to by lenp.
- *
- * returns:
- * pointer to the structure representing the property
- * if lenp is non-NULL, *lenp contains the length of the property
- * value (>=0)
- * NULL, on error
- * if lenp is non-NULL, *lenp contains an error code (<0):
- * -FDT_ERR_NOTFOUND, node does not have named property
- * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE,
- * -FDT_ERR_BADSTRUCTURE,
- * -FDT_ERR_TRUNCATED, standard meanings
- */
-const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
- const char *name, int *lenp);
-static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
- const char *name,
- int *lenp)
-{
- return (struct fdt_property *)(uintptr_t)
- fdt_get_property(fdt, nodeoffset, name, lenp);
-}
-
-/**
- * fdt_getprop_by_offset - retrieve the value of a property at a given offset
- * @fdt: pointer to the device tree blob
- * @ffset: offset of the property to read
- * @namep: pointer to a string variable (will be overwritten) or NULL
- * @lenp: pointer to an integer variable (will be overwritten) or NULL
- *
- * fdt_getprop_by_offset() retrieves a pointer to the value of the
- * property at structure block offset 'offset' (this will be a pointer
- * to within the device blob itself, not a copy of the value). If
- * lenp is non-NULL, the length of the property value is also
- * returned, in the integer pointed to by lenp. If namep is non-NULL,
- * the property's namne will also be returned in the char * pointed to
- * by namep (this will be a pointer to within the device tree's string
- * block, not a new copy of the name).
- *
- * returns:
- * pointer to the property's value
- * if lenp is non-NULL, *lenp contains the length of the property
- * value (>=0)
- * if namep is non-NULL *namep contiains a pointer to the property
- * name.
- * NULL, on error
- * if lenp is non-NULL, *lenp contains an error code (<0):
- * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE,
- * -FDT_ERR_BADSTRUCTURE,
- * -FDT_ERR_TRUNCATED, standard meanings
- */
-const void *fdt_getprop_by_offset(const void *fdt, int offset,
- const char **namep, int *lenp);
-
-/**
- * fdt_getprop_namelen - get property value based on substring
- * @fdt: pointer to the device tree blob
- * @nodeoffset: offset of the node whose property to find
- * @name: name of the property to find
- * @namelen: number of characters of name to consider
- * @lenp: pointer to an integer variable (will be overwritten) or NULL
- *
- * Identical to fdt_getprop(), but only examine the first namelen
- * characters of name for matching the property name.
- */
-const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
- const char *name, int namelen, int *lenp);
-
-/**
- * fdt_getprop - retrieve the value of a given property
- * @fdt: pointer to the device tree blob
- * @nodeoffset: offset of the node whose property to find
- * @name: name of the property to find
- * @lenp: pointer to an integer variable (will be overwritten) or NULL
- *
- * fdt_getprop() retrieves a pointer to the value of the property
- * named 'name' of the node at offset nodeoffset (this will be a
- * pointer to within the device blob itself, not a copy of the value).
- * If lenp is non-NULL, the length of the property value is also
- * returned, in the integer pointed to by lenp.
- *
- * returns:
- * pointer to the property's value
- * if lenp is non-NULL, *lenp contains the length of the property
- * value (>=0)
- * NULL, on error
- * if lenp is non-NULL, *lenp contains an error code (<0):
- * -FDT_ERR_NOTFOUND, node does not have named property
- * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE,
- * -FDT_ERR_BADSTRUCTURE,
- * -FDT_ERR_TRUNCATED, standard meanings
- */
-const void *fdt_getprop(const void *fdt, int nodeoffset,
- const char *name, int *lenp);
-static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
- const char *name, int *lenp)
-{
- return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
-}
-
-/**
- * fdt_get_phandle - retrieve the phandle of a given node
- * @fdt: pointer to the device tree blob
- * @nodeoffset: structure block offset of the node
- *
- * fdt_get_phandle() retrieves the phandle of the device tree node at
- * structure block offset nodeoffset.
- *
- * returns:
- * the phandle of the node at nodeoffset, on success (!= 0, != -1)
- * 0, if the node has no phandle, or another error occurs
- */
-uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
-
-/**
- * fdt_get_alias_namelen - get alias based on substring
- * @fdt: pointer to the device tree blob
- * @name: name of the alias th look up
- * @namelen: number of characters of name to consider
- *
- * Identical to fdt_get_alias(), but only examine the first namelen
- * characters of name for matching the alias name.
- */
-const char *fdt_get_alias_namelen(const void *fdt,
- const char *name, int namelen);
-
-/**
- * fdt_get_alias - retreive the path referenced by a given alias
- * @fdt: pointer to the device tree blob
- * @name: name of the alias th look up
- *
- * fdt_get_alias() retrieves the value of a given alias. That is, the
- * value of the property named 'name' in the node /aliases.
- *
- * returns:
- * a pointer to the expansion of the alias named 'name', of it exists
- * NULL, if the given alias or the /aliases node does not exist
- */
-const char *fdt_get_alias(const void *fdt, const char *name);
-
-/**
- * fdt_get_path - determine the full path of a node
- * @fdt: pointer to the device tree blob
- * @nodeoffset: offset of the node whose path to find
- * @buf: character buffer to contain the returned path (will be overwritten)
- * @buflen: size of the character buffer at buf
- *
- * fdt_get_path() computes the full path of the node at offset
- * nodeoffset, and records that path in the buffer at buf.
- *
- * NOTE: This function is expensive, as it must scan the device tree
- * structure from the start to nodeoffset.
- *
- * returns:
- * 0, on success
- * buf contains the absolute path of the node at
- * nodeoffset, as a NUL-terminated string.
- * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
- * -FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
- * characters and will not fit in the given buffer.
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE,
- * -FDT_ERR_BADSTRUCTURE, standard meanings
- */
-int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
-
-/**
- * fdt_supernode_atdepth_offset - find a specific ancestor of a node
- * @fdt: pointer to the device tree blob
- * @nodeoffset: offset of the node whose parent to find
- * @supernodedepth: depth of the ancestor to find
- * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
- *
- * fdt_supernode_atdepth_offset() finds an ancestor of the given node
- * at a specific depth from the root (where the root itself has depth
- * 0, its immediate subnodes depth 1 and so forth). So
- * fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
- * will always return 0, the offset of the root node. If the node at
- * nodeoffset has depth D, then:
- * fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
- * will return nodeoffset itself.
- *
- * NOTE: This function is expensive, as it must scan the device tree
- * structure from the start to nodeoffset.
- *
- * returns:
-
- * structure block offset of the node at node offset's ancestor
- * of depth supernodedepth (>=0), on success
- * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
-* -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of nodeoffset
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE,
- * -FDT_ERR_BADSTRUCTURE, standard meanings
- */
-int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
- int supernodedepth, int *nodedepth);
-
-/**
- * fdt_node_depth - find the depth of a given node
- * @fdt: pointer to the device tree blob
- * @nodeoffset: offset of the node whose parent to find
- *
- * fdt_node_depth() finds the depth of a given node. The root node
- * has depth 0, its immediate subnodes depth 1 and so forth.
- *
- * NOTE: This function is expensive, as it must scan the device tree
- * structure from the start to nodeoffset.
- *
- * returns:
- * depth of the node at nodeoffset (>=0), on success
- * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE,
- * -FDT_ERR_BADSTRUCTURE, standard meanings
- */
-int fdt_node_depth(const void *fdt, int nodeoffset);
-
-/**
- * fdt_parent_offset - find the parent of a given node
- * @fdt: pointer to the device tree blob
- * @nodeoffset: offset of the node whose parent to find
- *
- * fdt_parent_offset() locates the parent node of a given node (that
- * is, it finds the offset of the node which contains the node at
- * nodeoffset as a subnode).
- *
- * NOTE: This function is expensive, as it must scan the device tree
- * structure from the start to nodeoffset, *twice*.
- *
- * returns:
- * structure block offset of the parent of the node at nodeoffset
- * (>=0), on success
- * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE,
- * -FDT_ERR_BADSTRUCTURE, standard meanings
- */
-int fdt_parent_offset(const void *fdt, int nodeoffset);
-
-/**
- * fdt_node_offset_by_prop_value - find nodes with a given property value
- * @fdt: pointer to the device tree blob
- * @startoffset: only find nodes after this offset
- * @propname: property name to check
- * @propval: property value to search for
- * @proplen: length of the value in propval
- *
- * fdt_node_offset_by_prop_value() returns the offset of the first
- * node after startoffset, which has a property named propname whose
- * value is of length proplen and has value equal to propval; or if
- * startoffset is -1, the very first such node in the tree.
- *
- * To iterate through all nodes matching the criterion, the following
- * idiom can be used:
- * offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
- * propval, proplen);
- * while (offset != -FDT_ERR_NOTFOUND) {
- * ... other code here ...
- * offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
- * propval, proplen);
- * }
- *
- * Note the -1 in the first call to the function, if 0 is used here
- * instead, the function will never locate the root node, even if it
- * matches the criterion.
- *
- * returns:
- * structure block offset of the located node (>= 0, >startoffset),
- * on success
- * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
- * tree after startoffset
- * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
- * -FDT_ERR_BADMAGIC,
- * -FDT_ERR_BADVERSION,
- * -FDT_ERR_BADSTATE,
- * -FDT_ERR_BADSTRUCTURE, standard meanings