u-boot/include/libfdt.h
Simon Glass f8a2d7a416 libfdt: Add a function to write a property placeholder
The existing function to add a new property to a tree being built requires
that the entire contents of the new property be passed in. For some
applications it is more convenient to be able to add the property contents
later, perhaps by reading from a file. This avoids double-buffering of the
contents.

Add a new function to support this and adust the existing fdt_property() to
use it.

Signed-off-by: Simon Glass <sjg@chromium.org>
2016-03-14 14:19:11 -04:00

1984 lines
73 KiB
C

#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: 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. */
/* Errors in device tree content */
#define FDT_ERR_BADNCELLS 14
/* FDT_ERR_BADNCELLS: Device tree has a #address-cells, #size-cells
* or similar property with a bad format or value */
#define FDT_ERR_TOODEEP 15
/* FDT_ERR_TOODEEP: The depth of a node has exceeded the internal
* libfdt limit. This can happen if you have more than
* FDT_MAX_DEPTH nested nodes. */
#define FDT_ERR_MAX 15
/**********************************************************************/
/* 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);
/**
* fdt_first_subnode() - get offset of first direct subnode
*
* @fdt: FDT blob
* @offset: Offset of node to check
* @return offset of first subnode, or -FDT_ERR_NOTFOUND if there is none
*/
int fdt_first_subnode(const void *fdt, int offset);
/**
* fdt_next_subnode() - get offset of next direct subnode
*
* After first calling fdt_first_subnode(), call this function repeatedly to
* get direct subnodes of a parent node.
*
* @fdt: FDT blob
* @offset: Offset of previous subnode
* @return offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more
* subnodes
*/
int fdt_next_subnode(const void *fdt, int offset);
/**
* fdt_for_each_subnode - iterate over all subnodes of a parent
*
* This is actually a wrapper around a for loop and would be used like so:
*
* fdt_for_each_subnode(fdt, node, parent) {
* ...
* use node
* ...
* }
*
* Note that this is implemented as a macro and node is used as iterator in
* the loop. It should therefore be a locally allocated variable. The parent
* variable on the other hand is never modified, so it can be constant or
* even a literal.
*
* @fdt: FDT blob (const void *)
* @node: child node (int)
* @parent: parent node (int)
*/
#define fdt_for_each_subnode(fdt, node, parent) \
for (node = fdt_first_subnode(fdt, parent); \
node >= 0; \
node = fdt_next_subnode(fdt, node))
/**********************************************************************/
/* 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', if 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
*/
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);
/**
* fdt_stringlist_contains - check a string list property for a string
* @strlist: Property containing a list of strings to check
* @listlen: Length of property
* @str: String to search for
*
* This is a utility function provided for convenience. The list contains
* one or more strings, each terminated by \0, as is found in a device tree
* "compatible" property.
*
* @return: 1 if the string is found in the list, 0 not found, or invalid list
*/
int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
/**
* fdt_count_strings - count the number of strings in a string list
* @fdt: pointer to the device tree blob
* @node: offset of the node
* @property: name of the property containing the string list
* @return: the number of strings in the given property
*/
int fdt_count_strings(const void *fdt, int node, const char *property);
/**
* fdt_find_string - find a string in a string list and return its index
* @fdt: pointer to the device tree blob
* @node: offset of the node
* @property: name of the property containing the string list
* @string: string to look up in the string list
* @return: the index of the string or negative on error
*/
int fdt_find_string(const void *fdt, int node, const char *property,
const char *string);
/**
* fdt_get_string_index() - obtain the string at a given index in a string list
* @fdt: pointer to the device tree blob
* @node: offset of the node
* @property: name of the property containing the string list
* @index: index of the string to return
* @output: return location for the string
* @return: 0 if the string was found or a negative error code otherwise
*/
int fdt_get_string_index(const void *fdt, int node, const char *property,
int index, const char **output);
/**
* fdt_get_string() - obtain the first string in a string list
* @fdt: pointer to the device tree blob
* @node: offset of the node
* @property: name of the property containing the string list
* @output: return location for the string
* @return: 0 if the string was found or a negative error code otherwise
*
* This is a shortcut for:
*
* fdt_get_string_index(fdt, node, property, 0, output).
*/
int fdt_get_string(const void *fdt, int node, const char *property,
const char **output);
/**********************************************************************/
/* Read-only functions (addressing related) */
/**********************************************************************/
/**
* FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells
*
* This is the maximum value for #address-cells, #size-cells and
* similar properties that will be processed by libfdt. IEE1275
* requires that OF implementations handle values up to 4.
* Implementations may support larger values, but in practice higher
* values aren't used.
*/
#define FDT_MAX_NCELLS 4
/**
* fdt_address_cells - retrieve address size for a bus represented in the tree
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of the node to find the address size for
*
* When the node has a valid #address-cells property, returns its value.
*
* returns:
* 0 <= n < FDT_MAX_NCELLS, on success
* 2, if the node has no #address-cells property
* -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
* #address-cells property
* -FDT_ERR_BADMAGIC,
* -FDT_ERR_BADVERSION,
* -FDT_ERR_BADSTATE,
* -FDT_ERR_BADSTRUCTURE,
* -FDT_ERR_TRUNCATED, standard meanings
*/
int fdt_address_cells(const void *fdt, int nodeoffset);
/**
* fdt_size_cells - retrieve address range size for a bus represented in the
* tree
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of the node to find the address range size for
*
* When the node has a valid #size-cells property, returns its value.
*
* returns:
* 0 <= n < FDT_MAX_NCELLS, on success
* 2, if the node has no #address-cells property
* -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
* #size-cells property
* -FDT_ERR_BADMAGIC,
* -FDT_ERR_BADVERSION,
* -FDT_ERR_BADSTATE,
* -FDT_ERR_BADSTRUCTURE,
* -FDT_ERR_TRUNCATED, standard meanings
*/
int fdt_size_cells(const void *fdt, int nodeoffset);
/**********************************************************************/
/* 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_u32 - change the value of a 32-bit integer 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: 32-bit integer value to replace the property with
*
* fdt_setprop_inplace_u32() replaces the value of a given property
* with the 32-bit integer 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_u32(void *fdt, int nodeoffset,
const char *name, uint32_t val)
{
fdt32_t tmp = cpu_to_fdt32(val);
return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
}
/**
* fdt_setprop_inplace_u64 - change the value of a 64-bit integer 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: 64-bit integer value to replace the property with
*
* fdt_setprop_inplace_u64() replaces the value of a given property
* with the 64-bit integer 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
* 8.
*
* 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 8
* -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_u64(void *fdt, int nodeoffset,
const char *name, uint64_t val)
{
fdt64_t tmp = cpu_to_fdt64(val);
return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
}
/**
* fdt_setprop_inplace_cell - change the value of a single-cell property
*
* This is an alternative name for fdt_setprop_inplace_u32()
*/
static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
const char *name, uint32_t val)
{
return fdt_setprop_inplace_u32(fdt, nodeoffset, name, 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_resize(void *fdt, 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_u32(void *fdt, const char *name, uint32_t val)
{
fdt32_t tmp = cpu_to_fdt32(val);
return fdt_property(fdt, name, &tmp, sizeof(tmp));
}
static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
{
fdt64_t tmp = cpu_to_fdt64(val);
return fdt_property(fdt, name, &tmp, sizeof(tmp));
}
static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
{
return fdt_property_u32(fdt, name, val);
}
/**
* fdt_property_placeholder - add a new property and return a ptr to its value
*
* @fdt: pointer to the device tree blob
* @name: name of property to add
* @len: length of property value in bytes
* @valp: returns a pointer to where where the value should be placed
*
* returns:
* 0, on success
* -FDT_ERR_BADMAGIC,
* -FDT_ERR_NOSPACE, standard meanings
*/
int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp);
#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_create_empty_tree(void *buf, int bufsize);
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_u32 - set a property to a 32-bit integer
* @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_u32() sets the value of the named property in the given
* node to the given 32-bit integer 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_u32(void *fdt, int nodeoffset, const char *name,
uint32_t val)
{
fdt32_t tmp = cpu_to_fdt32(val);
return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
}
/**
* fdt_setprop_u64 - set a property to a 64-bit integer
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of the node whose property to change
* @name: name of the property to change
* @val: 64-bit integer value for the property (native endian)
*
* fdt_setprop_u64() sets the value of the named property in the given
* node to the given 64-bit integer 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_u64(void *fdt, int nodeoffset, const char *name,
uint64_t val)
{
fdt64_t tmp = cpu_to_fdt64(val);
return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
}
/**
* fdt_setprop_cell - set a property to a single cell value
*
* This is an alternative name for fdt_setprop_u32()
*/
static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
uint32_t val)
{
return fdt_setprop_u32(fdt, nodeoffset, name, 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_appendprop - append to or create a property
* @fdt: pointer to the device tree blob
* @nodeoffset: offset of the node whose property to change
* @name: name of the property to append to
* @val: pointer to data to append to the property value
* @len: length of the data to append to the property value
*
* fdt_appendprop() appends the value to the named property in the
* given node, creating the property if it does not already exist.
*
* This function may insert data into 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_appendprop(void *fdt, int nodeoffset, const char *name,
const void *val, int len);
/**
* fdt_appendprop_u32 - append a 32-bit integer value to 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: 32-bit integer value to append to the property (native endian)
*
* fdt_appendprop_u32() appends the given 32-bit integer value
* (converting to big-endian if necessary) to the value of the named
* property in the given node, or creates a new property with that
* value if it does not already exist.
*
* This function may insert data into 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_appendprop_u32(void *fdt, int nodeoffset,
const char *name, uint32_t val)
{
fdt32_t tmp = cpu_to_fdt32(val);
return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
}
/**
* fdt_appendprop_u64 - append a 64-bit integer value to 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: 64-bit integer value to append to the property (native endian)
*
* fdt_appendprop_u64() appends the given 64-bit integer value
* (converting to big-endian if necessary) to the value of the named
* property in the given node, or creates a new property with that
* value if it does not already exist.
*
* This function may insert data into 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_appendprop_u64(void *fdt, int nodeoffset,
const char *name, uint64_t val)
{
fdt64_t tmp = cpu_to_fdt64(val);
return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
}
/**
* fdt_appendprop_cell - append a single cell value to a property
*
* This is an alternative name for fdt_appendprop_u32()
*/
static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
const char *name, uint32_t val)
{
return fdt_appendprop_u32(fdt, nodeoffset, name, val);
}
/**
* fdt_appendprop_string - append a string to 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
* @str: string value to append to the property
*
* fdt_appendprop_string() appends the given string to the value of
* the named property in the given node, or creates a new property
* with that value if it does not already exist.
*
* This function may insert data into 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_appendprop_string(fdt, nodeoffset, name, str) \
fdt_appendprop((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);
/**
* fdt_remove_unused_strings() - Remove any unused strings from an FDT
*
* This creates a new device tree in @new with unused strings removed. The
* called can then use fdt_pack() to minimise the space consumed.
*
* @old: Old device tree blog
* @new: Place to put new device tree blob, which must be as large as
* @old
* @return
* 0, on success
* -FDT_ERR_BADOFFSET, corrupt device tree
* -FDT_ERR_NOSPACE, out of space, which should not happen unless there
* is something very wrong with the device tree input
*/
int fdt_remove_unused_strings(const void *old, void *new);
struct fdt_region {
int offset;
int size;
};
/*
* Flags for fdt_find_regions()
*
* Add a region for the string table (always the last region)
*/
#define FDT_REG_ADD_STRING_TAB (1 << 0)
/*
* Add all supernodes of a matching node/property, useful for creating a
* valid subset tree
*/
#define FDT_REG_SUPERNODES (1 << 1)
/* Add the FDT_BEGIN_NODE tags of subnodes, including their names */
#define FDT_REG_DIRECT_SUBNODES (1 << 2)
/* Add all subnodes of a matching node */
#define FDT_REG_ALL_SUBNODES (1 << 3)
/* Add a region for the mem_rsvmap table (always the first region) */
#define FDT_REG_ADD_MEM_RSVMAP (1 << 4)
/* Indicates what an fdt part is (node, property, value) */
#define FDT_IS_NODE (1 << 0)
#define FDT_IS_PROP (1 << 1)
#define FDT_IS_VALUE (1 << 2) /* not supported */
#define FDT_IS_COMPAT (1 << 3) /* used internally */
#define FDT_NODE_HAS_PROP (1 << 4) /* node contains prop */
#define FDT_ANY_GLOBAL (FDT_IS_NODE | FDT_IS_PROP | FDT_IS_VALUE | \
FDT_IS_COMPAT)
#define FDT_IS_ANY 0x1f /* all the above */
/* We set a reasonable limit on the number of nested nodes */
#define FDT_MAX_DEPTH 32
/* Decribes what we want to include from the current tag */
enum want_t {
WANT_NOTHING,
WANT_NODES_ONLY, /* No properties */
WANT_NODES_AND_PROPS, /* Everything for one level */
WANT_ALL_NODES_AND_PROPS /* Everything for all levels */
};
/* Keeps track of the state at parent nodes */
struct fdt_subnode_stack {
int offset; /* Offset of node */
enum want_t want; /* The 'want' value here */
int included; /* 1 if we included this node, 0 if not */
};
struct fdt_region_ptrs {
int depth; /* Current tree depth */
int done; /* What we have completed scanning */
enum want_t want; /* What we are currently including */
char *end; /* Pointer to end of full node path */
int nextoffset; /* Next node offset to check */
};
/* The state of our finding algortihm */
struct fdt_region_state {
struct fdt_subnode_stack stack[FDT_MAX_DEPTH]; /* node stack */
struct fdt_region *region; /* Contains list of regions found */
int count; /* Numnber of regions found */
const void *fdt; /* FDT blob */
int max_regions; /* Maximum regions to find */
int can_merge; /* 1 if we can merge with previous region */
int start; /* Start position of current region */
struct fdt_region_ptrs ptrs; /* Pointers for what we are up to */
};
/**
* fdt_find_regions() - find regions in device tree
*
* Given a list of nodes to include and properties to exclude, find
* the regions of the device tree which describe those included parts.
*
* The intent is to get a list of regions which will be invariant provided
* those parts are invariant. For example, if you request a list of regions
* for all nodes but exclude the property "data", then you will get the
* same region contents regardless of any change to "data" properties.
*
* This function can be used to produce a byte-stream to send to a hashing
* function to verify that critical parts of the FDT have not changed.
*
* Nodes which are given in 'inc' are included in the region list, as
* are the names of the immediate subnodes nodes (but not the properties
* or subnodes of those subnodes).
*
* For eaxample "/" means to include the root node, all root properties
* and the FDT_BEGIN_NODE and FDT_END_NODE of all subnodes of /. The latter
* ensures that we capture the names of the subnodes. In a hashing situation
* it prevents the root node from changing at all Any change to non-excluded
* properties, names of subnodes or number of subnodes would be detected.
*
* When used with FITs this provides the ability to hash and sign parts of
* the FIT based on different configurations in the FIT. Then it is
* impossible to change anything about that configuration (include images
* attached to the configuration), but it may be possible to add new
* configurations, new images or new signatures within the existing
* framework.
*
* Adding new properties to a device tree may result in the string table
* being extended (if the new property names are different from those
* already added). This function can optionally include a region for
* the string table so that this can be part of the hash too.
*
* The device tree header is not included in the list.
*
* @fdt: Device tree to check
* @inc: List of node paths to included
* @inc_count: Number of node paths in list
* @exc_prop: List of properties names to exclude
* @exc_prop_count: Number of properties in exclude list
* @region: Returns list of regions
* @max_region: Maximum length of region list
* @path: Pointer to a temporary string for the function to use for
* building path names
* @path_len: Length of path, must be large enough to hold the longest
* path in the tree
* @add_string_tab: 1 to add a region for the string table
* @return number of regions in list. If this is >max_regions then the
* region array was exhausted. You should increase max_regions and try
* the call again.
*/
int fdt_find_regions(const void *fdt, char * const inc[], int inc_count,
char * const exc_prop[], int exc_prop_count,
struct fdt_region region[], int max_regions,
char *path, int path_len, int add_string_tab);
/**
* fdt_first_region() - find regions in device tree
*
* Given a nodes and properties to include and properties to exclude, find
* the regions of the device tree which describe those included parts.
*
* The use for this function is twofold. Firstly it provides a convenient
* way of performing a structure-aware grep of the tree. For example it is
* possible to grep for a node and get all the properties associated with
* that node. Trees can be subsetted easily, by specifying the nodes that
* are required, and then writing out the regions returned by this function.
* This is useful for small resource-constrained systems, such as boot
* loaders, which want to use an FDT but do not need to know about all of
* it.
*
* Secondly it makes it easy to hash parts of the tree and detect changes.
* The intent is to get a list of regions which will be invariant provided
* those parts are invariant. For example, if you request a list of regions
* for all nodes but exclude the property "data", then you will get the
* same region contents regardless of any change to "data" properties.
*
* This function can be used to produce a byte-stream to send to a hashing
* function to verify that critical parts of the FDT have not changed.
* Note that semantically null changes in order could still cause false
* hash misses. Such reordering might happen if the tree is regenerated
* from source, and nodes are reordered (the bytes-stream will be emitted
* in a different order and mnay hash functions will detect this). However
* if an existing tree is modified using libfdt functions, such as
* fdt_add_subnode() and fdt_setprop(), then this problem is avoided.
*
* The nodes/properties to include/exclude are defined by a function
* provided by the caller. This function is called for each node and
* property, and must return:
*
* 0 - to exclude this part
* 1 - to include this part
* -1 - for FDT_IS_PROP only: no information is available, so include
* if its containing node is included
*
* The last case is only used to deal with properties. Often a property is
* included if its containing node is included - this is the case where
* -1 is returned.. However if the property is specifically required to be
* included/excluded, then 0 or 1 can be returned. Note that including a
* property when the FDT_REG_SUPERNODES flag is given will force its
* containing node to be included since it is not valid to have a property
* that is not in a node.
*
* Using the information provided, the inclusion of a node can be controlled
* either by a node name or its compatible string, or any other property
* that the function can determine.
*
* As an example, including node "/" means to include the root node and all
* root properties. A flag provides a way of also including supernodes (of
* which there is none for the root node), and another flag includes
* immediate subnodes, so in this case we would get the FDT_BEGIN_NODE and
* FDT_END_NODE of all subnodes of /.
*
* The subnode feature helps in a hashing situation since it prevents the
* root node from changing at all. Any change to non-excluded properties,
* names of subnodes or number of subnodes would be detected.
*
* When used with FITs this provides the ability to hash and sign parts of
* the FIT based on different configurations in the FIT. Then it is
* impossible to change anything about that configuration (include images
* attached to the configuration), but it may be possible to add new
* configurations, new images or new signatures within the existing
* framework.
*
* Adding new properties to a device tree may result in the string table
* being extended (if the new property names are different from those
* already added). This function can optionally include a region for
* the string table so that this can be part of the hash too. This is always
* the last region.
*
* The FDT also has a mem_rsvmap table which can also be included, and is
* always the first region if so.
*
* The device tree header is not included in the region list. Since the
* contents of the FDT are changing (shrinking, often), the caller will need
* to regenerate the header anyway.
*
* @fdt: Device tree to check
* @h_include: Function to call to determine whether to include a part or
* not:
*
* @priv: Private pointer as passed to fdt_find_regions()
* @fdt: Pointer to FDT blob
* @offset: Offset of this node / property
* @type: Type of this part, FDT_IS_...
* @data: Pointer to data (node name, property name, compatible
* string, value (not yet supported)
* @size: Size of data, or 0 if none
* @return 0 to exclude, 1 to include, -1 if no information is
* available
* @priv: Private pointer passed to h_include
* @region: Returns list of regions, sorted by offset
* @max_regions: Maximum length of region list
* @path: Pointer to a temporary string for the function to use for
* building path names
* @path_len: Length of path, must be large enough to hold the longest
* path in the tree
* @flags: Various flags that control the region algortihm, see
* FDT_REG_...
* @return number of regions in list. If this is >max_regions then the
* region array was exhausted. You should increase max_regions and try
* the call again. Only the first max_regions elements are available in the
* array.
*
* On error a -ve value is return, which can be:
*
* -FDT_ERR_BADSTRUCTURE (too deep or more END tags than BEGIN tags
* -FDT_ERR_BADLAYOUT
* -FDT_ERR_NOSPACE (path area is too small)
*/
int fdt_first_region(const void *fdt,
int (*h_include)(void *priv, const void *fdt, int offset,
int type, const char *data, int size),
void *priv, struct fdt_region *region,
char *path, int path_len, int flags,
struct fdt_region_state *info);
/** fdt_next_region() - find next region
*
* See fdt_first_region() for full description. This function finds the
* next region according to the provided parameters, which must be the same
* as passed to fdt_first_region().
*
* This function can additionally return -FDT_ERR_NOTFOUND when there are no
* more regions
*/
int fdt_next_region(const void *fdt,
int (*h_include)(void *priv, const void *fdt, int offset,
int type, const char *data, int size),
void *priv, struct fdt_region *region,
char *path, int path_len, int flags,
struct fdt_region_state *info);
/**
* fdt_add_alias_regions() - find aliases that point to existing regions
*
* Once a device tree grep is complete some of the nodes will be present
* and some will have been dropped. This function checks all the alias nodes
* to figure out which points point to nodes which are still present. These
* aliases need to be kept, along with the nodes they reference.
*
* Given a list of regions function finds the aliases that still apply and
* adds more regions to the list for these. This function is called after
* fdt_next_region() has finished returning regions and requires the same
* state.
*
* @fdt: Device tree file to reference
* @region: List of regions that will be kept
* @count: Number of regions
* @max_regions: Number of entries that can fit in @region
* @info: Region state as returned from fdt_next_region()
* @return new number of regions in @region (i.e. count + the number added)
* or -FDT_ERR_NOSPACE if there was not enough space.
*/
int fdt_add_alias_regions(const void *fdt, struct fdt_region *region, int count,
int max_regions, struct fdt_region_state *info);
#endif /* _LIBFDT_H */