* libfdt - Flat Device Tree manipulation
* Copyright (C) 2006 David Gibson, IBM Corporation.
*
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public License
- * as published by the Free Software Foundation; either version 2.1 of
- * the License, or (at your option) any later version.
+ * libfdt is dual licensed: you can use it either under the terms of
+ * the GPL, or the BSD license, at your option.
*
- * 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
- * Lesser General Public License for more details.
+ * 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.
*
- * You should have received a copy of the GNU Lesser 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
+ * 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 <fdt.h>
#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
-#define FDT_ERR_BADSTATE 6
+ /* 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 7
-#define FDT_ERR_BADMAGIC 8
-#define FDT_ERR_BADVERSION 9
-#define FDT_ERR_BADSTRUCTURE 10
-#define FDT_ERR_BADLAYOUT 11
+#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
-#define FDT_ERR_MAX 11
+/**********************************************************************/
+/* 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(((struct fdt_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_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_header(fdt, field, val) \
- ((struct fdt_header *)(fdt))->field = cpu_to_fdt32(val)
-
-void *fdt_offset_ptr(const void *fdt, int offset, int checklen);
+#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
-#define fdt_offset_ptr_typed(fdt, offset, var) \
- ((typeof(var))(fdt_offset_ptr((fdt), (offset), sizeof(*(var)))))
+/**
+ * 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 */
-char *fdt_string(const void *fdt, int stroffset);
+/**********************************************************************/
+/* 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);
-struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
- const char *name, int *lenp);
-void *fdt_getprop(const void *fdt, int nodeoffset,
- const char *name, int *lenp);
+/**
+ * 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);
+
-uint32_t fdt_next_tag(const void *fdt, int offset,
- int *nextoffset, char **namep);
+/**********************************************************************/
+/* Write-in-place functions */
+/**********************************************************************/
-/* 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);
-#define fdt_setprop_inplace_typed(fdt, nodeoffset, name, val) \
- ({ \
- typeof(val) x = val; \
- fdt_setprop_inplace(fdt, nodeoffset, name, &x, sizeof(x)); \
- })
+/**
+ * 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 */
+/**********************************************************************/
+/* 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);
-#define fdt_property_typed(fdt, name, val) \
- ({ \
- typeof(val) x = (val); \
- fdt_property((fdt), (name), &x, sizeof(x)); \
- })
+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);
+}
#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(void *fdt, void *buf, int bufsize);
+/**********************************************************************/
+/* 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);
-#define fdt_setprop_typed(fdt, nodeoffset, name, val) \
- ({ \
- typeof(val) x = (val); \
- fdt_setprop((fdt), (nodeoffset), (name), &x, sizeof(x)); \
- })
+
+/**
+ * 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);
-/* Extra functions */
+/**********************************************************************/
+/* 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 */