Move dtc and libfdt sources from arch/powerpc/boot to scripts/dtc

The powerpc kernel always requires an Open Firmware like device tree
to supply device information.  On systems without OF, this comes from
a flattened device tree blob.  This blob is usually generated by dtc,
a tool which compiles a text description of the device tree into the
flattened format used by the kernel.  Sometimes, the bootwrapper makes
small changes to the pre-compiled device tree blob (e.g. filling in
the size of RAM).  To do this it uses the libfdt library.

Because these are only used on powerpc, the code for both these tools
is included under arch/powerpc/boot (these were imported and are
periodically updated from the upstream dtc tree).

However, the microblaze architecture, currently being prepared for
merging to mainline also uses dtc to produce device tree blobs.  A few
other archs have also mentioned some interest in using dtc.
Therefore, this patch moves dtc and libfdt from arch/powerpc into
scripts, where it can be used by any architecture.

The vast bulk of this patch is a literal move, the rest is adjusting
the various Makefiles to use dtc and libfdt correctly from their new
locations.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1076 insertions, 0 deletions

diff --git a/scripts/dtc/libfdt/libfdt.h b/scripts/dtc/libfdt/libfdt.h
new file mode 100644
index 000000000000..ce80e4fb41b2
--- /dev/null
+++ b/scripts/dtc/libfdt/libfdt.h
@@ -0,0 +1,1076 @@
+#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 *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
+}
+
+uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
+
+/**********************************************************************/
+/* Traversal functions                                                */
+/**********************************************************************/
+
+int fdt_next_node(const void *fdt, int offset, int *depth);
+
+/**********************************************************************/
+/* General functions                                                  */
+/**********************************************************************/
+
+#define fdt_get_header(fdt, field) \
+        (fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
+#define fdt_magic(fdt)                  (fdt_get_header(fdt, magic))
+#define fdt_totalsize(fdt)              (fdt_get_header(fdt, totalsize))
+#define fdt_off_dt_struct(fdt)          (fdt_get_header(fdt, off_dt_struct))
+#define fdt_off_dt_strings(fdt)         (fdt_get_header(fdt, off_dt_strings))
+#define fdt_off_mem_rsvmap(fdt)         (fdt_get_header(fdt, off_mem_rsvmap))
+#define fdt_version(fdt)                (fdt_get_header(fdt, version))
+#define fdt_last_comp_version(fdt)      (fdt_get_header(fdt, last_comp_version))
+#define fdt_boot_cpuid_phys(fdt)        (fdt_get_header(fdt, boot_cpuid_phys))
+#define fdt_size_dt_strings(fdt)        (fdt_get_header(fdt, size_dt_strings))
+#define fdt_size_dt_struct(fdt)         (fdt_get_header(fdt, size_dt_struct))
+
+#define __fdt_set_hdr(name) \
+        static inline void fdt_set_##name(void *fdt, uint32_t val) \
+        { \
+                struct fdt_header *fdth = fdt; \
+                fdth->name = cpu_to_fdt32(val); \
+        }
+__fdt_set_hdr(magic);
+__fdt_set_hdr(totalsize);
+__fdt_set_hdr(off_dt_struct);
+__fdt_set_hdr(off_dt_strings);
+__fdt_set_hdr(off_mem_rsvmap);
+__fdt_set_hdr(version);
+__fdt_set_hdr(last_comp_version);
+__fdt_set_hdr(boot_cpuid_phys);
+__fdt_set_hdr(size_dt_strings);
+__fdt_set_hdr(size_dt_struct);
+#undef __fdt_set_hdr
+
+/**
+ * fdt_check_header - sanity check a device tree or possible device tree
+ * @fdt: pointer to data which might be a flattened device tree
+ *
+ * fdt_check_header() checks that the given buffer contains what
+ * appears to be a flattened device tree with sane information in its
+ * header.
+ *
+ * returns:
+ *     0, if the buffer appears to contain a valid device tree
+ *     -FDT_ERR_BADMAGIC,
+ *     -FDT_ERR_BADVERSION,
+ *     -FDT_ERR_BADSTATE, standard meanings, as above
+ */
+int fdt_check_header(const void *fdt);
+
+/**
+ * fdt_move - move a device tree around in memory
+ * @fdt: pointer to the device tree to move
+ * @buf: pointer to memory where the device is to be moved
+ * @bufsize: size of the memory space at buf
+ *
+ * fdt_move() relocates, if possible, the device tree blob located at
+ * fdt to the buffer at buf of size bufsize.  The buffer may overlap
+ * with the existing device tree blob at fdt.  Therefore,
+ *     fdt_move(fdt, fdt, fdt_totalsize(fdt))
+ * should always succeed.
+ *
+ * returns:
+ *     0, on success
+ *     -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
+ *     -FDT_ERR_BADMAGIC,
+ *     -FDT_ERR_BADVERSION,
+ *     -FDT_ERR_BADSTATE, standard meanings
+ */
+int fdt_move(const void *fdt, void *buf, int bufsize);
+
+/**********************************************************************/
+/* Read-only functions                                                */
+/**********************************************************************/
+
+/**
+ * fdt_string - retrieve a string from the strings block of a device tree
+ * @fdt: pointer to the device tree blob
+ * @stroffset: offset of the string within the strings block (native endian)
+ *
+ * fdt_string() retrieves a pointer to a single string from the
+ * strings block of the device tree blob at fdt.
+ *
+ * returns:
+ *     a pointer to the string, on success
+ *     NULL, if stroffset is out of bounds
+ */
+const char *fdt_string(const void *fdt, int stroffset);
+
+/**
+ * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
+ * @fdt: pointer to the device tree blob
+ *
+ * Returns the number of entries in the device tree blob's memory
+ * reservation map.  This does not include the terminating 0,0 entry
+ * or any other (0,0) entries reserved for expansion.
+ *
+ * returns:
+ *     the number of entries
+ */
+int fdt_num_mem_rsv(const void *fdt);
+
+/**
+ * fdt_get_mem_rsv - retrieve one memory reserve map entry
+ * @fdt: pointer to the device tree blob
+ * @address, @size: pointers to 64-bit variables
+ *
+ * On success, *address and *size will contain the address and size of
+ * the n-th reserve map entry from the device tree blob, in
+ * native-endian format.
+ *
+ * returns:
+ *     0, on success
+ *     -FDT_ERR_BADMAGIC,
+ *     -FDT_ERR_BADVERSION,
+ *     -FDT_ERR_BADSTATE, standard meanings
+ */
+int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
+
+/**
+ * fdt_subnode_offset_namelen - find a subnode based on substring
+ * @fdt: pointer to the device tree blob
+ * @parentoffset: structure block offset of a node
+ * @name: name of the subnode to locate
+ * @namelen: number of characters of name to consider
+ *
+ * Identical to fdt_subnode_offset(), but only examine the first
+ * namelen characters of name for matching the subnode name.  This is
+ * useful for finding subnodes based on a portion of a larger string,
+ * such as a full path.
+ */
+int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
+                               const char *name, int namelen);
+/**
+ * fdt_subnode_offset - find a subnode of a given node
+ * @fdt: pointer to the device tree blob
+ * @parentoffset: structure block offset of a node
+ * @name: name of the subnode to locate
+ *
+ * fdt_subnode_offset() finds a subnode of the node at structure block
+ * offset parentoffset with the given name.  name may include a unit
+ * address, in which case fdt_subnode_offset() will find the subnode
+ * with that unit address, or the unit address may be omitted, in
+ * which case fdt_subnode_offset() will find an arbitrary subnode
+ * whose name excluding unit address matches the given name.
+ *
+ * returns:
+ *      structure block offset of the requested subnode (>=0), on success
+ *      -FDT_ERR_NOTFOUND, if the requested subnode does not exist
+ *      -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_TRUNCATED, standard meanings.
+ */
+int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
+
+/**
+ * fdt_path_offset - find a tree node by its full path
+ * @fdt: pointer to the device tree blob
+ * @path: full path of the node to locate
+ *
+ * fdt_path_offset() finds a node of a given path in the device tree.
+ * Each path component may omit the unit address portion, but the
+ * results of this are undefined if any such path component is
+ * ambiguous (that is if there are multiple nodes at the relevant
+ * level matching the given component, differentiated only by unit
+ * address).
+ *
+ * returns:
+ *      structure block offset of the node with the requested path (>=0), on success
+ *      -FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
+ *      -FDT_ERR_NOTFOUND, if the requested node does not exist
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_TRUNCATED, standard meanings.
+ */
+int fdt_path_offset(const void *fdt, const char *path);
+
+/**
+ * fdt_get_name - retrieve the name of a given node
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: structure block offset of the starting node
+ * @lenp: pointer to an integer variable (will be overwritten) or NULL
+ *
+ * fdt_get_name() retrieves the name (including unit address) of the
+ * device tree node at structure block offset nodeoffset.  If lenp is
+ * non-NULL, the length of this name is also returned, in the integer
+ * pointed to by lenp.
+ *
+ * returns:
+ *      pointer to the node's name, on success
+ *              If lenp is non-NULL, *lenp contains the length of that name (>=0)
+ *      NULL, on error
+ *              if lenp is non-NULL *lenp contains an error code (<0):
+ *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *              -FDT_ERR_BADMAGIC,
+ *              -FDT_ERR_BADVERSION,
+ *              -FDT_ERR_BADSTATE, standard meanings
+ */
+const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
+
+/**
+ * fdt_get_property - find a given property in a given node
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to find
+ * @name: name of the property to find
+ * @lenp: pointer to an integer variable (will be overwritten) or NULL
+ *
+ * fdt_get_property() retrieves a pointer to the fdt_property
+ * structure within the device tree blob corresponding to the property
+ * named 'name' of the node at offset nodeoffset.  If lenp is
+ * non-NULL, the length of the property value is also returned, in the
+ * integer pointed to by lenp.
+ *
+ * returns:
+ *      pointer to the structure representing the property
+ *              if lenp is non-NULL, *lenp contains the length of the property
+ *              value (>=0)
+ *      NULL, on error
+ *              if lenp is non-NULL, *lenp contains an error code (<0):
+ *              -FDT_ERR_NOTFOUND, node does not have named property
+ *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *              -FDT_ERR_BADMAGIC,
+ *              -FDT_ERR_BADVERSION,
+ *              -FDT_ERR_BADSTATE,
+ *              -FDT_ERR_BADSTRUCTURE,
+ *              -FDT_ERR_TRUNCATED, standard meanings
+ */
+const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
+                                            const char *name, int *lenp);
+static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
+                                                      const char *name,
+                                                      int *lenp)
+{
+        return (struct fdt_property *)(uintptr_t)
+                fdt_get_property(fdt, nodeoffset, name, lenp);
+}
+
+/**
+ * fdt_getprop - retrieve the value of a given property
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to find
+ * @name: name of the property to find
+ * @lenp: pointer to an integer variable (will be overwritten) or NULL
+ *
+ * fdt_getprop() retrieves a pointer to the value of the property
+ * named 'name' of the node at offset nodeoffset (this will be a
+ * pointer to within the device blob itself, not a copy of the value).
+ * If lenp is non-NULL, the length of the property value is also
+ * returned, in the integer pointed to by lenp.
+ *
+ * returns:
+ *      pointer to the property's value
+ *              if lenp is non-NULL, *lenp contains the length of the property
+ *              value (>=0)
+ *      NULL, on error
+ *              if lenp is non-NULL, *lenp contains an error code (<0):
+ *              -FDT_ERR_NOTFOUND, node does not have named property
+ *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *              -FDT_ERR_BADMAGIC,
+ *              -FDT_ERR_BADVERSION,
+ *              -FDT_ERR_BADSTATE,
+ *              -FDT_ERR_BADSTRUCTURE,
+ *              -FDT_ERR_TRUNCATED, standard meanings
+ */
+const void *fdt_getprop(const void *fdt, int nodeoffset,
+                        const char *name, int *lenp);
+static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
+                                  const char *name, int *lenp)
+{
+        return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
+}
+
+/**
+ * fdt_get_phandle - retrieve the phandle of a given node
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: structure block offset of the node
+ *
+ * fdt_get_phandle() retrieves the phandle of the device tree node at
+ * structure block offset nodeoffset.
+ *
+ * returns:
+ *      the phandle of the node at nodeoffset, on success (!= 0, != -1)
+ *      0, if the node has no phandle, or another error occurs
+ */
+uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
+
+/**
+ * fdt_get_path - determine the full path of a node
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose path to find
+ * @buf: character buffer to contain the returned path (will be overwritten)
+ * @buflen: size of the character buffer at buf
+ *
+ * fdt_get_path() computes the full path of the node at offset
+ * nodeoffset, and records that path in the buffer at buf.
+ *
+ * NOTE: This function is expensive, as it must scan the device tree
+ * structure from the start to nodeoffset.
+ *
+ * returns:
+ *      0, on success
+ *              buf contains the absolute path of the node at
+ *              nodeoffset, as a NUL-terminated string.
+ *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *      -FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
+ *              characters and will not fit in the given buffer.
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE, standard meanings
+ */
+int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
+
+/**
+ * fdt_supernode_atdepth_offset - find a specific ancestor of a node
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose parent to find
+ * @supernodedepth: depth of the ancestor to find
+ * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
+ *
+ * fdt_supernode_atdepth_offset() finds an ancestor of the given node
+ * at a specific depth from the root (where the root itself has depth
+ * 0, its immediate subnodes depth 1 and so forth).  So
+ *      fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
+ * will always return 0, the offset of the root node.  If the node at
+ * nodeoffset has depth D, then:
+ *      fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
+ * will return nodeoffset itself.
+ *
+ * NOTE: This function is expensive, as it must scan the device tree
+ * structure from the start to nodeoffset.
+ *
+ * returns:
+
+ *      structure block offset of the node at node offset's ancestor
+ *              of depth supernodedepth (>=0), on success
+ *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+*       -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of nodeoffset
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE, standard meanings
+ */
+int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
+                                 int supernodedepth, int *nodedepth);
+
+/**
+ * fdt_node_depth - find the depth of a given node
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose parent to find
+ *
+ * fdt_node_depth() finds the depth of a given node.  The root node
+ * has depth 0, its immediate subnodes depth 1 and so forth.
+ *
+ * NOTE: This function is expensive, as it must scan the device tree
+ * structure from the start to nodeoffset.
+ *
+ * returns:
+ *      depth of the node at nodeoffset (>=0), on success
+ *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE, standard meanings
+ */
+int fdt_node_depth(const void *fdt, int nodeoffset);
+
+/**
+ * fdt_parent_offset - find the parent of a given node
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose parent to find
+ *
+ * fdt_parent_offset() locates the parent node of a given node (that
+ * is, it finds the offset of the node which contains the node at
+ * nodeoffset as a subnode).
+ *
+ * NOTE: This function is expensive, as it must scan the device tree
+ * structure from the start to nodeoffset, *twice*.
+ *
+ * returns:
+ *      structure block offset of the parent of the node at nodeoffset
+ *              (>=0), on success
+ *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE, standard meanings
+ */
+int fdt_parent_offset(const void *fdt, int nodeoffset);
+
+/**
+ * fdt_node_offset_by_prop_value - find nodes with a given property value
+ * @fdt: pointer to the device tree blob
+ * @startoffset: only find nodes after this offset
+ * @propname: property name to check
+ * @propval: property value to search for
+ * @proplen: length of the value in propval
+ *
+ * fdt_node_offset_by_prop_value() returns the offset of the first
+ * node after startoffset, which has a property named propname whose
+ * value is of length proplen and has value equal to propval; or if
+ * startoffset is -1, the very first such node in the tree.
+ *
+ * To iterate through all nodes matching the criterion, the following
+ * idiom can be used:
+ *      offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
+ *                                             propval, proplen);
+ *      while (offset != -FDT_ERR_NOTFOUND) {
+ *              // other code here
+ *              offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
+ *                                                     propval, proplen);
+ *      }
+ *
+ * Note the -1 in the first call to the function, if 0 is used here
+ * instead, the function will never locate the root node, even if it
+ * matches the criterion.
+ *
+ * returns:
+ *      structure block offset of the located node (>= 0, >startoffset),
+ *               on success
+ *      -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
+ *              tree after startoffset
+ *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE, standard meanings
+ */
+int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
+                                  const char *propname,
+                                  const void *propval, int proplen);
+
+/**
+ * fdt_node_offset_by_phandle - find the node with a given phandle
+ * @fdt: pointer to the device tree blob
+ * @phandle: phandle value
+ *
+ * fdt_node_offset_by_phandle() returns the offset of the node
+ * which has the given phandle value.  If there is more than one node
+ * in the tree with the given phandle (an invalid tree), results are
+ * undefined.
+ *
+ * returns:
+ *      structure block offset of the located node (>= 0), on success
+ *      -FDT_ERR_NOTFOUND, no node with that phandle exists
+ *      -FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE, standard meanings
+ */
+int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
+
+/**
+ * fdt_node_check_compatible: check a node's compatible property
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of a tree node
+ * @compatible: string to match against
+ *
+ *
+ * fdt_node_check_compatible() returns 0 if the given node contains a
+ * 'compatible' property with the given string as one of its elements,
+ * it returns non-zero otherwise, or on error.
+ *
+ * returns:
+ *      0, if the node has a 'compatible' property listing the given string
+ *      1, if the node has a 'compatible' property, but it does not list
+ *              the given string
+ *      -FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
+ *      -FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE, standard meanings
+ */
+int fdt_node_check_compatible(const void *fdt, int nodeoffset,
+                              const char *compatible);
+
+/**
+ * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
+ * @fdt: pointer to the device tree blob
+ * @startoffset: only find nodes after this offset
+ * @compatible: 'compatible' string to match against
+ *
+ * fdt_node_offset_by_compatible() returns the offset of the first
+ * node after startoffset, which has a 'compatible' property which
+ * lists the given compatible string; or if startoffset is -1, the
+ * very first such node in the tree.
+ *
+ * To iterate through all nodes matching the criterion, the following
+ * idiom can be used:
+ *      offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
+ *      while (offset != -FDT_ERR_NOTFOUND) {
+ *              // other code here
+ *              offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
+ *      }
+ *
+ * Note the -1 in the first call to the function, if 0 is used here
+ * instead, the function will never locate the root node, even if it
+ * matches the criterion.
+ *
+ * returns:
+ *      structure block offset of the located node (>= 0, >startoffset),
+ *               on success
+ *      -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
+ *              tree after startoffset
+ *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE, standard meanings
+ */
+int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
+                                  const char *compatible);
+
+/**********************************************************************/
+/* Write-in-place functions                                           */
+/**********************************************************************/
+
+/**
+ * fdt_setprop_inplace - change a property's value, but not its size
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @val: pointer to data to replace the property value with
+ * @len: length of the property value
+ *
+ * fdt_setprop_inplace() replaces the value of a given property with
+ * the data in val, of length len.  This function cannot change the
+ * size of a property, and so will only work if len is equal to the
+ * current length of the property.
+ *
+ * This function will alter only the bytes in the blob which contain
+ * the given property value, and will not alter or move any other part
+ * of the tree.
+ *
+ * returns:
+ *      0, on success
+ *      -FDT_ERR_NOSPACE, if len is not equal to the property's current length
+ *      -FDT_ERR_NOTFOUND, node does not have the named property
+ *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
+                        const void *val, int len);
+
+/**
+ * fdt_setprop_inplace_cell - change the value of a single-cell property
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @val: cell (32-bit integer) value to replace the property with
+ *
+ * fdt_setprop_inplace_cell() replaces the value of a given property
+ * with the 32-bit integer cell value in val, converting val to
+ * big-endian if necessary.  This function cannot change the size of a
+ * property, and so will only work if the property already exists and
+ * has length 4.
+ *
+ * This function will alter only the bytes in the blob which contain
+ * the given property value, and will not alter or move any other part
+ * of the tree.
+ *
+ * returns:
+ *      0, on success
+ *      -FDT_ERR_NOSPACE, if the property's length is not equal to 4
+  *     -FDT_ERR_NOTFOUND, node does not have the named property
+ *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_TRUNCATED, standard meanings
+ */
+static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
+                                           const char *name, uint32_t val)
+{
+        val = cpu_to_fdt32(val);
+        return fdt_setprop_inplace(fdt, nodeoffset, name, &val, sizeof(val));
+}
+
+/**
+ * fdt_nop_property - replace a property with nop tags
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to nop
+ * @name: name of the property to nop
+ *
+ * fdt_nop_property() will replace a given property's representation
+ * in the blob with FDT_NOP tags, effectively removing it from the
+ * tree.
+ *
+ * This function will alter only the bytes in the blob which contain
+ * the property, and will not alter or move any other part of the
+ * tree.
+ *
+ * returns:
+ *      0, on success
+ *      -FDT_ERR_NOTFOUND, node does not have the named property
+ *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
+
+/**
+ * fdt_nop_node - replace a node (subtree) with nop tags
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node to nop
+ *
+ * fdt_nop_node() will replace a given node's representation in the
+ * blob, including all its subnodes, if any, with FDT_NOP tags,
+ * effectively removing it from the tree.
+ *
+ * This function will alter only the bytes in the blob which contain
+ * the node and its properties and subnodes, and will not alter or
+ * move any other part of the tree.
+ *
+ * returns:
+ *      0, on success
+ *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_nop_node(void *fdt, int nodeoffset);
+
+/**********************************************************************/
+/* Sequential write functions                                         */
+/**********************************************************************/
+
+int fdt_create(void *buf, int bufsize);
+int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
+int fdt_finish_reservemap(void *fdt);
+int fdt_begin_node(void *fdt, const char *name);
+int fdt_property(void *fdt, const char *name, const void *val, int len);
+static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
+{
+        val = cpu_to_fdt32(val);
+        return fdt_property(fdt, name, &val, sizeof(val));
+}
+#define fdt_property_string(fdt, name, str) \
+        fdt_property(fdt, name, str, strlen(str)+1)
+int fdt_end_node(void *fdt);
+int fdt_finish(void *fdt);
+
+/**********************************************************************/
+/* Read-write functions                                               */
+/**********************************************************************/
+
+int fdt_open_into(const void *fdt, void *buf, int bufsize);
+int fdt_pack(void *fdt);
+
+/**
+ * fdt_add_mem_rsv - add one memory reserve map entry
+ * @fdt: pointer to the device tree blob
+ * @address, @size: 64-bit values (native endian)
+ *
+ * Adds a reserve map entry to the given blob reserving a region at
+ * address address of length size.
+ *
+ * This function will insert data into the reserve map and will
+ * therefore change the indexes of some entries in the table.
+ *
+ * returns:
+ *      0, on success
+ *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
+ *              contain the new reservation entry
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_BADLAYOUT,
+ *      -FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
+
+/**
+ * fdt_del_mem_rsv - remove a memory reserve map entry
+ * @fdt: pointer to the device tree blob
+ * @n: entry to remove
+ *
+ * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
+ * the blob.
+ *
+ * This function will delete data from the reservation table and will
+ * therefore change the indexes of some entries in the table.
+ *
+ * returns:
+ *      0, on success
+ *      -FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
+ *              are less than n+1 reserve map entries)
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_BADLAYOUT,
+ *      -FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_del_mem_rsv(void *fdt, int n);
+
+/**
+ * fdt_set_name - change the name of a given node
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: structure block offset of a node
+ * @name: name to give the node
+ *
+ * fdt_set_name() replaces the name (including unit address, if any)
+ * of the given node with the given string.  NOTE: this function can't
+ * efficiently check if the new name is unique amongst the given
+ * node's siblings; results are undefined if this function is invoked
+ * with a name equal to one of the given node's siblings.
+ *
+ * This function may insert or delete data from the blob, and will
+ * therefore change the offsets of some existing nodes.
+ *
+ * returns:
+ *      0, on success
+ *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob
+ *              to contain the new name
+ *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE, standard meanings
+ */
+int fdt_set_name(void *fdt, int nodeoffset, const char *name);
+
+/**
+ * fdt_setprop - create or change a property
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @val: pointer to data to set the property value to
+ * @len: length of the property value
+ *
+ * fdt_setprop() sets the value of the named property in the given
+ * node to the given value and length, creating the property if it
+ * does not already exist.
+ *
+ * This function may insert or delete data from the blob, and will
+ * therefore change the offsets of some existing nodes.
+ *
+ * returns:
+ *      0, on success
+ *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
+ *              contain the new property value
+ *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *      -FDT_ERR_BADLAYOUT,
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_BADLAYOUT,
+ *      -FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_setprop(void *fdt, int nodeoffset, const char *name,
+                const void *val, int len);
+
+/**
+ * fdt_setprop_cell - set a property to a single cell value
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @val: 32-bit integer value for the property (native endian)
+ *
+ * fdt_setprop_cell() sets the value of the named property in the
+ * given node to the given cell value (converting to big-endian if
+ * necessary), or creates a new property with that value if it does
+ * not already exist.
+ *
+ * This function may insert or delete data from the blob, and will
+ * therefore change the offsets of some existing nodes.
+ *
+ * returns:
+ *      0, on success
+ *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
+ *              contain the new property value
+ *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *      -FDT_ERR_BADLAYOUT,
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_BADLAYOUT,
+ *      -FDT_ERR_TRUNCATED, standard meanings
+ */
+static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
+                                   uint32_t val)
+{
+        val = cpu_to_fdt32(val);
+        return fdt_setprop(fdt, nodeoffset, name, &val, sizeof(val));
+}
+
+/**
+ * fdt_setprop_string - set a property to a string value
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @str: string value for the property
+ *
+ * fdt_setprop_string() sets the value of the named property in the
+ * given node to the given string value (using the length of the
+ * string to determine the new length of the property), or creates a
+ * new property with that value if it does not already exist.
+ *
+ * This function may insert or delete data from the blob, and will
+ * therefore change the offsets of some existing nodes.
+ *
+ * returns:
+ *      0, on success
+ *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
+ *              contain the new property value
+ *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *      -FDT_ERR_BADLAYOUT,
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_BADLAYOUT,
+ *      -FDT_ERR_TRUNCATED, standard meanings
+ */
+#define fdt_setprop_string(fdt, nodeoffset, name, str) \
+        fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
+
+/**
+ * fdt_delprop - delete a property
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to nop
+ * @name: name of the property to nop
+ *
+ * fdt_del_property() will delete the given property.
+ *
+ * This function will delete data from the blob, and will therefore
+ * change the offsets of some existing nodes.
+ *
+ * returns:
+ *      0, on success
+ *      -FDT_ERR_NOTFOUND, node does not have the named property
+ *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *      -FDT_ERR_BADLAYOUT,
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_delprop(void *fdt, int nodeoffset, const char *name);
+
+/**
+ * fdt_add_subnode_namelen - creates a new node based on substring
+ * @fdt: pointer to the device tree blob
+ * @parentoffset: structure block offset of a node
+ * @name: name of the subnode to locate
+ * @namelen: number of characters of name to consider
+ *
+ * Identical to fdt_add_subnode(), but use only the first namelen
+ * characters of name as the name of the new node.  This is useful for
+ * creating subnodes based on a portion of a larger string, such as a
+ * full path.
+ */
+int fdt_add_subnode_namelen(void *fdt, int parentoffset,
+                            const char *name, int namelen);
+
+/**
+ * fdt_add_subnode - creates a new node
+ * @fdt: pointer to the device tree blob
+ * @parentoffset: structure block offset of a node
+ * @name: name of the subnode to locate
+ *
+ * fdt_add_subnode() creates a new node as a subnode of the node at
+ * structure block offset parentoffset, with the given name (which
+ * should include the unit address, if any).
+ *
+ * This function will insert data into the blob, and will therefore
+ * change the offsets of some existing nodes.
+
+ * returns:
+ *      structure block offset of the created nodeequested subnode (>=0), on success
+ *      -FDT_ERR_NOTFOUND, if the requested subnode does not exist
+ *      -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
+ *      -FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
+ *              the given name
+ *      -FDT_ERR_NOSPACE, if there is insufficient free space in the
+ *              blob to contain the new node
+ *      -FDT_ERR_NOSPACE
+ *      -FDT_ERR_BADLAYOUT
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_TRUNCATED, standard meanings.
+ */
+int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
+
+/**
+ * fdt_del_node - delete a node (subtree)
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node to nop
+ *
+ * fdt_del_node() will remove the given node, including all its
+ * subnodes if any, from the blob.
+ *
+ * This function will delete data from the blob, and will therefore
+ * change the offsets of some existing nodes.
+ *
+ * returns:
+ *      0, on success
+ *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *      -FDT_ERR_BADLAYOUT,
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_del_node(void *fdt, int nodeoffset);
+
+/**********************************************************************/
+/* Debugging / informational functions                                */
+/**********************************************************************/
+
+const char *fdt_strerror(int errval);
+
+#endif /* _LIBFDT_H */