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authorDavid Gibson <david@gibson.dropbear.id.au>2007-12-10 14:28:39 +1100
committerPaul Mackerras <paulus@samba.org>2007-12-11 13:46:13 +1100
commit1cade99497c881a8c719df561d1bdc96831ff040 (patch)
treed90f0f9c667c5379f79244d117f4c95299180a05 /arch/powerpc/boot/libfdt/libfdt.h
parent[POWERPC] EEH: Avoid a possible NULL pointer dereference (diff)
downloadlinux-dev-1cade99497c881a8c719df561d1bdc96831ff040.tar.xz
linux-dev-1cade99497c881a8c719df561d1bdc96831ff040.zip
[POWERPC] Merge libfdt upstream source
This incorporates a copy of dtc libfdt into the kernel source, in arch/powerpc/boot/libfdt. This only imports the upstream sources verbatim, later patches are needed to actually link it into the kernel Makefiles. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/boot/libfdt/libfdt.h')
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diff --git a/arch/powerpc/boot/libfdt/libfdt.h b/arch/powerpc/boot/libfdt/libfdt.h
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+++ b/arch/powerpc/boot/libfdt/libfdt.h
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+#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. */
+
+#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 *)fdt_offset_ptr(fdt, offset, checklen);
+}
+
+uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
+
+/**********************************************************************/
+/* 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 - retreive 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 - retreive 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 - retreive 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 - retreive 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 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 *)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 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 *)fdt_getprop(fdt, nodeoffset, name, lenp);
+}
+
+/**
+ * fdt_get_phandle - retreive 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 succes (!= 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:
+ * stucture 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_prop_value() 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 */
+/**********************************************************************/
+
+int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
+ const void *val, int len);
+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));
+}
+
+int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
+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);
+
+int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
+int fdt_del_mem_rsv(void *fdt, int n);
+
+int fdt_setprop(void *fdt, int nodeoffset, const char *name,
+ const void *val, int len);
+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));
+}
+#define fdt_setprop_string(fdt, nodeoffset, name, str) \
+ fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
+int fdt_delprop(void *fdt, int nodeoffset, const char *name);
+int fdt_add_subnode_namelen(void *fdt, int parentoffset,
+ const char *name, int namelen);
+int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
+int fdt_del_node(void *fdt, int nodeoffset);
+
+/**********************************************************************/
+/* Debugging / informational functions */
+/**********************************************************************/
+
+const char *fdt_strerror(int errval);
+
+#endif /* _LIBFDT_H */