libfdt.h
#ifndef _LIBFDT_H
#define _LIBFDT_H
/*
* 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: Attempted 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, 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 = 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_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 - 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_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
*/
int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
const char *propname,
const void *propval, int proplen);
/**
* fdt_node_offset_by_phandle - find the node with a given phandle
* @fdt: pointer to the device tree blob
* @phandle: phandle value
*
* fdt_node_offset_by_phandle() returns the offset of the node
* which has the given phandle value. If there is more than one node
* in the tree with the given phandle (an invalid tree), results are
* undefined.
*
* returns:
* structure block offset of the located node (>= 0), on success
* -FDT_ERR_NOTFOUND, no node with that phandle exists
* -FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
* -FDT_ERR_BADMAGIC,
* -FDT_ERR_BADVERSION,
* -FDT_ERR_BADSTATE,
* -FDT_ERR_BADSTRUCTURE, standard meanings
*/
int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
/**
* fdt_node_check_compatible: check a node's compatible property
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of a tree node
* @compatible: string to match against
*
*
* fdt_node_check_compatible() returns 0 if the given node contains a
* 'compatible' property with the given string as one of its elements,
* it returns non-zero otherwise, or on error.
*
* returns:
* 0, if the node has a 'compatible' property listing the given string
* 1, if the node has a 'compatible' property, but it does not list
* the given string
* -FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
* -FDT_ERR_BADOFFSET, if 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_check_compatible(const void *fdt, int nodeoffset,
const char *compatible);
/**
* fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
* @fdt: pointer to the device tree blob
* @startoffset: only find nodes after this offset
* @compatible: 'compatible' string to match against
*
* fdt_node_offset_by_compatible() returns the offset of the first
* node after startoffset, which has a 'compatible' property which
* lists the given compatible string; 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_compatible(fdt, -1, compatible);
* while (offset != -FDT_ERR_NOTFOUND) {
* // other code here
* offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
* }
*
* 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
*/
int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
const char *compatible);
/**********************************************************************/
/* Write-in-place functions */
/**********************************************************************/
/**
* fdt_setprop_inplace - change a property's value, but not its size
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of the node whose property to change
* @name: name of the property to change
* @val: pointer to data to replace the property value with
* @len: length of the property value
*
* fdt_setprop_inplace() replaces the value of a given property with
* the data in val, of length len. This function cannot change the
* size of a property, and so will only work if len is equal to the
* current length of the property.
*
* This function will alter only the bytes in the blob which contain
* the given property value, and will not alter or move any other part
* of the tree.
*
* returns:
* 0, on success
* -FDT_ERR_NOSPACE, if len is not equal to the property's current length
* -FDT_ERR_NOTFOUND, node does not have the 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
*/
int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
const void *val, int len);
/**
* fdt_setprop_inplace_cell - change the value of a single-cell property
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of the node whose property to change
* @name: name of the property to change
* @val: cell (32-bit integer) value to replace the property with
*
* fdt_setprop_inplace_cell() replaces the value of a given property
* with the 32-bit integer cell value in val, converting val to
* big-endian if necessary. This function cannot change the size of a
* property, and so will only work if the property already exists and
* has length 4.
*
* This function will alter only the bytes in the blob which contain
* the given property value, and will not alter or move any other part
* of the tree.
*
* returns:
* 0, on success
* -FDT_ERR_NOSPACE, if the property's length is not equal to 4
* -FDT_ERR_NOTFOUND, node does not have the 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
*/
static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
const char *name, uint32_t val)
{
val = cpu_to_fdt32(val);
return fdt_setprop_inplace(fdt, nodeoffset, name, &val, sizeof(val));
}
/**
* fdt_nop_property - replace a property with nop tags
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of the node whose property to nop
* @name: name of the property to nop
*
* fdt_nop_property() will replace a given property's representation
* in the blob with FDT_NOP tags, effectively removing it from the
* tree.
*
* This function will alter only the bytes in the blob which contain
* the property, and will not alter or move any other part of the
* tree.
*
* returns:
* 0, on success
* -FDT_ERR_NOTFOUND, node does not have the 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
*/
int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
/**
* fdt_nop_node - replace a node (subtree) with nop tags
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of the node to nop
*
* fdt_nop_node() will replace a given node's representation in the
* blob, including all its subnodes, if any, with FDT_NOP tags,
* effectively removing it from the tree.
*
* This function will alter only the bytes in the blob which contain
* the node and its properties and subnodes, and will not alter or
* move any other part of the tree.
*
* returns:
* 0, on success
* -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
*/
int fdt_nop_node(void *fdt, int nodeoffset);
/**********************************************************************/
/* Sequential write functions */
/**********************************************************************/
int fdt_create(void *buf, int bufsize);
int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
int fdt_finish_reservemap(void *fdt);
int fdt_begin_node(void *fdt, const char *name);
int fdt_property(void *fdt, const char *name, const void *val, int len);
static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
{
val = cpu_to_fdt32(val);
return fdt_property(fdt, name, &val, sizeof(val));
}
#define fdt_property_string(fdt, name, str) \
fdt_property(fdt, name, str, strlen(str)+1)
int fdt_end_node(void *fdt);
int fdt_finish(void *fdt);
/**********************************************************************/
/* Read-write functions */
/**********************************************************************/
int fdt_open_into(const void *fdt, void *buf, int bufsize);
int fdt_pack(void *fdt);
/**
* fdt_add_mem_rsv - add one memory reserve map entry
* @fdt: pointer to the device tree blob
* @address, @size: 64-bit values (native endian)
*
* Adds a reserve map entry to the given blob reserving a region at
* address address of length size.
*
* This function will insert data into the reserve map and will
* therefore change the indexes of some entries in the table.
*
* returns:
* 0, on success
* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
* contain the new reservation entry
* -FDT_ERR_BADMAGIC,
* -FDT_ERR_BADVERSION,
* -FDT_ERR_BADSTATE,
* -FDT_ERR_BADSTRUCTURE,
* -FDT_ERR_BADLAYOUT,
* -FDT_ERR_TRUNCATED, standard meanings
*/
int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
/**
* fdt_del_mem_rsv - remove a memory reserve map entry
* @fdt: pointer to the device tree blob
* @n: entry to remove
*
* fdt_del_mem_rsv() removes the n-th memory reserve map entry from
* the blob.
*
* This function will delete data from the reservation table and will
* therefore change the indexes of some entries in the table.
*
* returns:
* 0, on success
* -FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
* are less than n+1 reserve map entries)
* -FDT_ERR_BADMAGIC,
* -FDT_ERR_BADVERSION,
* -FDT_ERR_BADSTATE,
* -FDT_ERR_BADSTRUCTURE,
* -FDT_ERR_BADLAYOUT,
* -FDT_ERR_TRUNCATED, standard meanings
*/
int fdt_del_mem_rsv(void *fdt, int n);
/**
* fdt_set_name - change the name of a given node
* @fdt: pointer to the device tree blob
* @nodeoffset: structure block offset of a node
* @name: name to give the node
*
* fdt_set_name() replaces the name (including unit address, if any)
* of the given node with the given string. NOTE: this function can't
* efficiently check if the new name is unique amongst the given
* node's siblings; results are undefined if this function is invoked
* with a name equal to one of the given node's siblings.
*
* This function may insert or delete data from the blob, and will
* therefore change the offsets of some existing nodes.
*
* returns:
* 0, on success
* -FDT_ERR_NOSPACE, there is insufficient free space in the blob
* to contain the new name
* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
* -FDT_ERR_BADMAGIC,
* -FDT_ERR_BADVERSION,
* -FDT_ERR_BADSTATE, standard meanings
*/
int fdt_set_name(void *fdt, int nodeoffset, const char *name);
/**
* fdt_setprop - create or change a property
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of the node whose property to change
* @name: name of the property to change
* @val: pointer to data to set the property value to
* @len: length of the property value
*
* fdt_setprop() sets the value of the named property in the given
* node to the given value and length, creating the property if it
* does not already exist.
*
* This function may insert or delete data from the blob, and will
* therefore change the offsets of some existing nodes.
*
* returns:
* 0, on success
* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
* contain the new property value
* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
* -FDT_ERR_BADLAYOUT,
* -FDT_ERR_BADMAGIC,
* -FDT_ERR_BADVERSION,
* -FDT_ERR_BADSTATE,
* -FDT_ERR_BADSTRUCTURE,
* -FDT_ERR_BADLAYOUT,
* -FDT_ERR_TRUNCATED, standard meanings
*/
int fdt_setprop(void *fdt, int nodeoffset, const char *name,
const void *val, int len);
/**
* fdt_setprop_cell - set a property to a single cell value
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of the node whose property to change
* @name: name of the property to change
* @val: 32-bit integer value for the property (native endian)
*
* fdt_setprop_cell() sets the value of the named property in the
* given node to the given cell value (converting to big-endian if
* necessary), or creates a new property with that value if it does
* not already exist.
*
* This function may insert or delete data from the blob, and will
* therefore change the offsets of some existing nodes.
*
* returns:
* 0, on success
* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
* contain the new property value
* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
* -FDT_ERR_BADLAYOUT,
* -FDT_ERR_BADMAGIC,
* -FDT_ERR_BADVERSION,
* -FDT_ERR_BADSTATE,
* -FDT_ERR_BADSTRUCTURE,
* -FDT_ERR_BADLAYOUT,
* -FDT_ERR_TRUNCATED, standard meanings
*/
static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
uint32_t val)
{
val = cpu_to_fdt32(val);
return fdt_setprop(fdt, nodeoffset, name, &val, sizeof(val));
}
/**
* fdt_setprop_string - set a property to a string value
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of the node whose property to change
* @name: name of the property to change
* @str: string value for the property
*
* fdt_setprop_string() sets the value of the named property in the
* given node to the given string value (using the length of the
* string to determine the new length of the property), or creates a
* new property with that value if it does not already exist.
*
* This function may insert or delete data from the blob, and will
* therefore change the offsets of some existing nodes.
*
* returns:
* 0, on success
* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
* contain the new property value
* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
* -FDT_ERR_BADLAYOUT,
* -FDT_ERR_BADMAGIC,
* -FDT_ERR_BADVERSION,
* -FDT_ERR_BADSTATE,
* -FDT_ERR_BADSTRUCTURE,
* -FDT_ERR_BADLAYOUT,
* -FDT_ERR_TRUNCATED, standard meanings
*/
#define fdt_setprop_string(fdt, nodeoffset, name, str) \
fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
/**
* fdt_delprop - delete a property
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of the node whose property to nop
* @name: name of the property to nop
*
* fdt_del_property() will delete the given property.
*
* This function will delete data from the blob, and will therefore
* change the offsets of some existing nodes.
*
* returns:
* 0, on success
* -FDT_ERR_NOTFOUND, node does not have the named property
* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
* -FDT_ERR_BADLAYOUT,
* -FDT_ERR_BADMAGIC,
* -FDT_ERR_BADVERSION,
* -FDT_ERR_BADSTATE,
* -FDT_ERR_BADSTRUCTURE,
* -FDT_ERR_TRUNCATED, standard meanings
*/
int fdt_delprop(void *fdt, int nodeoffset, const char *name);
/**
* fdt_add_subnode_namelen - creates a new node 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_add_subnode(), but use only the first namelen
* characters of name as the name of the new node. This is useful for
* creating subnodes based on a portion of a larger string, such as a
* full path.
*/
int fdt_add_subnode_namelen(void *fdt, int parentoffset,
const char *name, int namelen);
/**
* fdt_add_subnode - creates a new node
* @fdt: pointer to the device tree blob
* @parentoffset: structure block offset of a node
* @name: name of the subnode to locate
*
* fdt_add_subnode() creates a new node as a subnode of the node at
* structure block offset parentoffset, with the given name (which
* should include the unit address, if any).
*
* This function will insert data into the blob, and will therefore
* change the offsets of some existing nodes.
* returns:
* structure block offset of the created nodeequested 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_EXISTS, if the node at parentoffset already has a subnode of
* the given name
* -FDT_ERR_NOSPACE, if there is insufficient free space in the
* blob to contain the new node
* -FDT_ERR_NOSPACE
* -FDT_ERR_BADLAYOUT
* -FDT_ERR_BADMAGIC,
* -FDT_ERR_BADVERSION,
* -FDT_ERR_BADSTATE,
* -FDT_ERR_BADSTRUCTURE,
* -FDT_ERR_TRUNCATED, standard meanings.
*/
int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
/**
* fdt_del_node - delete a node (subtree)
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of the node to nop
*
* fdt_del_node() will remove the given node, including all its
* subnodes if any, from the blob.
*
* This function will delete data from the blob, and will therefore
* change the offsets of some existing nodes.
*
* returns:
* 0, on success
* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
* -FDT_ERR_BADLAYOUT,
* -FDT_ERR_BADMAGIC,
* -FDT_ERR_BADVERSION,
* -FDT_ERR_BADSTATE,
* -FDT_ERR_BADSTRUCTURE,
* -FDT_ERR_TRUNCATED, standard meanings
*/
int fdt_del_node(void *fdt, int nodeoffset);
/**********************************************************************/
/* Debugging / informational functions */
/**********************************************************************/
const char *fdt_strerror(int errval);
#endif /* _LIBFDT_H */