#ifndef _LIBFDT_H #define _LIBFDT_H /* * libfdt - Flat Device Tree manipulation * Copyright (C) 2006 David Gibson, IBM Corporation. * * libfdt is dual licensed: you can use it either under the terms of * the GPL, or the BSD license, at your option. * * a) This library is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of the * License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this library; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, * MA 02110-1301 USA * * Alternatively, * * b) Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * 1. Redistributions of source code must retain the above * copyright notice, this list of conditions and the following * disclaimer. * 2. Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials * provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include <libfdt_env.h> #include <fdt.h> #define FDT_FIRST_SUPPORTED_VERSION 0x10 #define FDT_LAST_SUPPORTED_VERSION 0x11 /* Error codes: informative error codes */ #define FDT_ERR_NOTFOUND 1 /* FDT_ERR_NOTFOUND: The requested node or property does not exist */ #define FDT_ERR_EXISTS 2 /* FDT_ERR_EXISTS: Attemped to create a node or property which * already exists */ #define FDT_ERR_NOSPACE 3 /* FDT_ERR_NOSPACE: Operation needed to expand the device * tree, but its buffer did not have sufficient space to * contain the expanded tree. Use fdt_open_into() to move the * device tree to a buffer with more space. */ /* Error codes: codes for bad parameters */ #define FDT_ERR_BADOFFSET 4 /* FDT_ERR_BADOFFSET: Function was passed a structure block * offset which is out-of-bounds, or which points to an * unsuitable part of the structure for the operation. */ #define FDT_ERR_BADPATH 5 /* FDT_ERR_BADPATH: Function was passed a badly formatted path * (e.g. missing a leading / for a function which requires an * absolute path) */ #define FDT_ERR_BADPHANDLE 6 /* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle * value. phandle values of 0 and -1 are not permitted. */ #define FDT_ERR_BADSTATE 7 /* FDT_ERR_BADSTATE: Function was passed an incomplete device * tree created by the sequential-write functions, which is * not sufficiently complete for the requested operation. */ /* Error codes: codes for bad device tree blobs */ #define FDT_ERR_TRUNCATED 8 /* FDT_ERR_TRUNCATED: Structure block of the given device tree * ends without an FDT_END tag. */ #define FDT_ERR_BADMAGIC 9 /* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a * device tree at all - it is missing the flattened device * tree magic number. */ #define FDT_ERR_BADVERSION 10 /* FDT_ERR_BADVERSION: Given device tree has a version which * can't be handled by the requested operation. For * read-write functions, this may mean that fdt_open_into() is * required to convert the tree to the expected version. */ #define FDT_ERR_BADSTRUCTURE 11 /* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt * structure block or other serious error (e.g. misnested * nodes, or subnodes preceding properties). */ #define FDT_ERR_BADLAYOUT 12 /* FDT_ERR_BADLAYOUT: For read-write functions, the given * device tree has it's sub-blocks in an order that the * function can't handle (memory reserve map, then structure, * then strings). Use fdt_open_into() to reorganize the tree * into a form suitable for the read-write operations. */ /* "Can't happen" error indicating a bug in libfdt */ #define FDT_ERR_INTERNAL 13 /* FDT_ERR_INTERNAL: libfdt has failed an internal assertion. * Should never be returned, if it is, it indicates a bug in * libfdt itself. */ /* Errors in device tree content */ #define FDT_ERR_BADNCELLS 14 /* FDT_ERR_BADNCELLS: Device tree has a #address-cells, #size-cells * or similar property with a bad format or value */ #define FDT_ERR_TOODEEP 15 /* FDT_ERR_TOODEEP: The depth of a node has exceeded the internal * libfdt limit. This can happen if you have more than * FDT_MAX_DEPTH nested nodes. */ #define FDT_ERR_MAX 15 /**********************************************************************/ /* Low-level functions (you probably don't need these) */ /**********************************************************************/ const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen); static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen) { return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen); } uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset); /**********************************************************************/ /* Traversal functions */ /**********************************************************************/ int fdt_next_node(const void *fdt, int offset, int *depth); /** * fdt_first_subnode() - get offset of first direct subnode * * @fdt: FDT blob * @offset: Offset of node to check * @return offset of first subnode, or -FDT_ERR_NOTFOUND if there is none */ int fdt_first_subnode(const void *fdt, int offset); /** * fdt_next_subnode() - get offset of next direct subnode * * After first calling fdt_first_subnode(), call this function repeatedly to * get direct subnodes of a parent node. * * @fdt: FDT blob * @offset: Offset of previous subnode * @return offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more * subnodes */ int fdt_next_subnode(const void *fdt, int offset); /** * fdt_for_each_subnode - iterate over all subnodes of a parent * * This is actually a wrapper around a for loop and would be used like so: * * fdt_for_each_subnode(fdt, node, parent) { * ... * use node * ... * } * * Note that this is implemented as a macro and node is used as iterator in * the loop. It should therefore be a locally allocated variable. The parent * variable on the other hand is never modified, so it can be constant or * even a literal. * * @fdt: FDT blob (const void *) * @node: child node (int) * @parent: parent node (int) */ #define fdt_for_each_subnode(fdt, node, parent) \ for (node = fdt_first_subnode(fdt, parent); \ node >= 0; \ node = fdt_next_subnode(fdt, node)) /**********************************************************************/ /* General functions */ /**********************************************************************/ #define fdt_get_header(fdt, field) \ (fdt32_to_cpu(((const struct fdt_header *)(fdt))->field)) #define fdt_magic(fdt) (fdt_get_header(fdt, magic)) #define fdt_totalsize(fdt) (fdt_get_header(fdt, totalsize)) #define fdt_off_dt_struct(fdt) (fdt_get_header(fdt, off_dt_struct)) #define fdt_off_dt_strings(fdt) (fdt_get_header(fdt, off_dt_strings)) #define fdt_off_mem_rsvmap(fdt) (fdt_get_header(fdt, off_mem_rsvmap)) #define fdt_version(fdt) (fdt_get_header(fdt, version)) #define fdt_last_comp_version(fdt) (fdt_get_header(fdt, last_comp_version)) #define fdt_boot_cpuid_phys(fdt) (fdt_get_header(fdt, boot_cpuid_phys)) #define fdt_size_dt_strings(fdt) (fdt_get_header(fdt, size_dt_strings)) #define fdt_size_dt_struct(fdt) (fdt_get_header(fdt, size_dt_struct)) #define __fdt_set_hdr(name) \ static inline void fdt_set_##name(void *fdt, uint32_t val) \ { \ struct fdt_header *fdth = (struct fdt_header*)fdt; \ fdth->name = cpu_to_fdt32(val); \ } __fdt_set_hdr(magic); __fdt_set_hdr(totalsize); __fdt_set_hdr(off_dt_struct); __fdt_set_hdr(off_dt_strings); __fdt_set_hdr(off_mem_rsvmap); __fdt_set_hdr(version); __fdt_set_hdr(last_comp_version); __fdt_set_hdr(boot_cpuid_phys); __fdt_set_hdr(size_dt_strings); __fdt_set_hdr(size_dt_struct); #undef __fdt_set_hdr /** * fdt_check_header - sanity check a device tree or possible device tree * @fdt: pointer to data which might be a flattened device tree * * fdt_check_header() checks that the given buffer contains what * appears to be a flattened device tree with sane information in its * header. * * returns: * 0, if the buffer appears to contain a valid device tree * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, standard meanings, as above */ int fdt_check_header(const void *fdt); /** * fdt_move - move a device tree around in memory * @fdt: pointer to the device tree to move * @buf: pointer to memory where the device is to be moved * @bufsize: size of the memory space at buf * * fdt_move() relocates, if possible, the device tree blob located at * fdt to the buffer at buf of size bufsize. The buffer may overlap * with the existing device tree blob at fdt. Therefore, * fdt_move(fdt, fdt, fdt_totalsize(fdt)) * should always succeed. * * returns: * 0, on success * -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, standard meanings */ int fdt_move(const void *fdt, void *buf, int bufsize); /**********************************************************************/ /* Read-only functions */ /**********************************************************************/ /** * fdt_string - retrieve a string from the strings block of a device tree * @fdt: pointer to the device tree blob * @stroffset: offset of the string within the strings block (native endian) * * fdt_string() retrieves a pointer to a single string from the * strings block of the device tree blob at fdt. * * returns: * a pointer to the string, on success * NULL, if stroffset is out of bounds */ const char *fdt_string(const void *fdt, int stroffset); /** * fdt_num_mem_rsv - retrieve the number of memory reserve map entries * @fdt: pointer to the device tree blob * * Returns the number of entries in the device tree blob's memory * reservation map. This does not include the terminating 0,0 entry * or any other (0,0) entries reserved for expansion. * * returns: * the number of entries */ int fdt_num_mem_rsv(const void *fdt); /** * fdt_get_mem_rsv - retrieve one memory reserve map entry * @fdt: pointer to the device tree blob * @address, @size: pointers to 64-bit variables * * On success, *address and *size will contain the address and size of * the n-th reserve map entry from the device tree blob, in * native-endian format. * * returns: * 0, on success * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, standard meanings */ int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size); /** * fdt_subnode_offset_namelen - find a subnode based on substring * @fdt: pointer to the device tree blob * @parentoffset: structure block offset of a node * @name: name of the subnode to locate * @namelen: number of characters of name to consider * * Identical to fdt_subnode_offset(), but only examine the first * namelen characters of name for matching the subnode name. This is * useful for finding subnodes based on a portion of a larger string, * such as a full path. */ int fdt_subnode_offset_namelen(const void *fdt, int parentoffset, const char *name, int namelen); /** * fdt_subnode_offset - find a subnode of a given node * @fdt: pointer to the device tree blob * @parentoffset: structure block offset of a node * @name: name of the subnode to locate * * fdt_subnode_offset() finds a subnode of the node at structure block * offset parentoffset with the given name. name may include a unit * address, in which case fdt_subnode_offset() will find the subnode * with that unit address, or the unit address may be omitted, in * which case fdt_subnode_offset() will find an arbitrary subnode * whose name excluding unit address matches the given name. * * returns: * structure block offset of the requested subnode (>=0), on success * -FDT_ERR_NOTFOUND, if the requested subnode does not exist * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings. */ int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name); /** * fdt_path_offset - find a tree node by its full path * @fdt: pointer to the device tree blob * @path: full path of the node to locate * * fdt_path_offset() finds a node of a given path in the device tree. * Each path component may omit the unit address portion, but the * results of this are undefined if any such path component is * ambiguous (that is if there are multiple nodes at the relevant * level matching the given component, differentiated only by unit * address). * * returns: * structure block offset of the node with the requested path (>=0), on success * -FDT_ERR_BADPATH, given path does not begin with '/' or is invalid * -FDT_ERR_NOTFOUND, if the requested node does not exist * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings. */ int fdt_path_offset(const void *fdt, const char *path); /** * fdt_get_name - retrieve the name of a given node * @fdt: pointer to the device tree blob * @nodeoffset: structure block offset of the starting node * @lenp: pointer to an integer variable (will be overwritten) or NULL * * fdt_get_name() retrieves the name (including unit address) of the * device tree node at structure block offset nodeoffset. If lenp is * non-NULL, the length of this name is also returned, in the integer * pointed to by lenp. * * returns: * pointer to the node's name, on success * If lenp is non-NULL, *lenp contains the length of that name (>=0) * NULL, on error * if lenp is non-NULL *lenp contains an error code (<0): * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, standard meanings */ const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp); /** * fdt_first_property_offset - find the offset of a node's first property * @fdt: pointer to the device tree blob * @nodeoffset: structure block offset of a node * * fdt_first_property_offset() finds the first property of the node at * the given structure block offset. * * returns: * structure block offset of the property (>=0), on success * -FDT_ERR_NOTFOUND, if the requested node has no properties * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings. */ int fdt_first_property_offset(const void *fdt, int nodeoffset); /** * fdt_next_property_offset - step through a node's properties * @fdt: pointer to the device tree blob * @offset: structure block offset of a property * * fdt_next_property_offset() finds the property immediately after the * one at the given structure block offset. This will be a property * of the same node as the given property. * * returns: * structure block offset of the next property (>=0), on success * -FDT_ERR_NOTFOUND, if the given property is the last in its node * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings. */ int fdt_next_property_offset(const void *fdt, int offset); /** * fdt_get_property_by_offset - retrieve the property at a given offset * @fdt: pointer to the device tree blob * @offset: offset of the property to retrieve * @lenp: pointer to an integer variable (will be overwritten) or NULL * * fdt_get_property_by_offset() retrieves a pointer to the * fdt_property structure within the device tree blob at the given * offset. If lenp is non-NULL, the length of the property value is * also returned, in the integer pointed to by lenp. * * returns: * pointer to the structure representing the property * if lenp is non-NULL, *lenp contains the length of the property * value (>=0) * NULL, on error * if lenp is non-NULL, *lenp contains an error code (<0): * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ const struct fdt_property *fdt_get_property_by_offset(const void *fdt, int offset, int *lenp); /** * fdt_get_property_namelen - find a property based on substring * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to find * @name: name of the property to find * @namelen: number of characters of name to consider * @lenp: pointer to an integer variable (will be overwritten) or NULL * * Identical to fdt_get_property_namelen(), but only examine the first * namelen characters of name for matching the property name. */ const struct fdt_property *fdt_get_property_namelen(const void *fdt, int nodeoffset, const char *name, int namelen, int *lenp); /** * fdt_get_property - find a given property in a given node * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to find * @name: name of the property to find * @lenp: pointer to an integer variable (will be overwritten) or NULL * * fdt_get_property() retrieves a pointer to the fdt_property * structure within the device tree blob corresponding to the property * named 'name' of the node at offset nodeoffset. If lenp is * non-NULL, the length of the property value is also returned, in the * integer pointed to by lenp. * * returns: * pointer to the structure representing the property * if lenp is non-NULL, *lenp contains the length of the property * value (>=0) * NULL, on error * if lenp is non-NULL, *lenp contains an error code (<0): * -FDT_ERR_NOTFOUND, node does not have named property * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset, const char *name, int *lenp); static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset, const char *name, int *lenp) { return (struct fdt_property *)(uintptr_t) fdt_get_property(fdt, nodeoffset, name, lenp); } /** * fdt_getprop_by_offset - retrieve the value of a property at a given offset * @fdt: pointer to the device tree blob * @ffset: offset of the property to read * @namep: pointer to a string variable (will be overwritten) or NULL * @lenp: pointer to an integer variable (will be overwritten) or NULL * * fdt_getprop_by_offset() retrieves a pointer to the value of the * property at structure block offset 'offset' (this will be a pointer * to within the device blob itself, not a copy of the value). If * lenp is non-NULL, the length of the property value is also * returned, in the integer pointed to by lenp. If namep is non-NULL, * the property's namne will also be returned in the char * pointed to * by namep (this will be a pointer to within the device tree's string * block, not a new copy of the name). * * returns: * pointer to the property's value * if lenp is non-NULL, *lenp contains the length of the property * value (>=0) * if namep is non-NULL *namep contiains a pointer to the property * name. * NULL, on error * if lenp is non-NULL, *lenp contains an error code (<0): * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ const void *fdt_getprop_by_offset(const void *fdt, int offset, const char **namep, int *lenp); /** * fdt_getprop_namelen - get property value based on substring * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to find * @name: name of the property to find * @namelen: number of characters of name to consider * @lenp: pointer to an integer variable (will be overwritten) or NULL * * Identical to fdt_getprop(), but only examine the first namelen * characters of name for matching the property name. */ const void *fdt_getprop_namelen(const void *fdt, int nodeoffset, const char *name, int namelen, int *lenp); /** * fdt_getprop - retrieve the value of a given property * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to find * @name: name of the property to find * @lenp: pointer to an integer variable (will be overwritten) or NULL * * fdt_getprop() retrieves a pointer to the value of the property * named 'name' of the node at offset nodeoffset (this will be a * pointer to within the device blob itself, not a copy of the value). * If lenp is non-NULL, the length of the property value is also * returned, in the integer pointed to by lenp. * * returns: * pointer to the property's value * if lenp is non-NULL, *lenp contains the length of the property * value (>=0) * NULL, on error * if lenp is non-NULL, *lenp contains an error code (<0): * -FDT_ERR_NOTFOUND, node does not have named property * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ const void *fdt_getprop(const void *fdt, int nodeoffset, const char *name, int *lenp); static inline void *fdt_getprop_w(void *fdt, int nodeoffset, const char *name, int *lenp) { return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp); } /** * fdt_get_phandle - retrieve the phandle of a given node * @fdt: pointer to the device tree blob * @nodeoffset: structure block offset of the node * * fdt_get_phandle() retrieves the phandle of the device tree node at * structure block offset nodeoffset. * * returns: * the phandle of the node at nodeoffset, on success (!= 0, != -1) * 0, if the node has no phandle, or another error occurs */ uint32_t fdt_get_phandle(const void *fdt, int nodeoffset); /** * fdt_get_alias_namelen - get alias based on substring * @fdt: pointer to the device tree blob * @name: name of the alias th look up * @namelen: number of characters of name to consider * * Identical to fdt_get_alias(), but only examine the first namelen * characters of name for matching the alias name. */ const char *fdt_get_alias_namelen(const void *fdt, const char *name, int namelen); /** * fdt_get_alias - retreive the path referenced by a given alias * @fdt: pointer to the device tree blob * @name: name of the alias th look up * * fdt_get_alias() retrieves the value of a given alias. That is, the * value of the property named 'name' in the node /aliases. * * returns: * a pointer to the expansion of the alias named 'name', if it exists * NULL, if the given alias or the /aliases node does not exist */ const char *fdt_get_alias(const void *fdt, const char *name); /** * fdt_get_path - determine the full path of a node * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose path to find * @buf: character buffer to contain the returned path (will be overwritten) * @buflen: size of the character buffer at buf * * fdt_get_path() computes the full path of the node at offset * nodeoffset, and records that path in the buffer at buf. * * NOTE: This function is expensive, as it must scan the device tree * structure from the start to nodeoffset. * * returns: * 0, on success * buf contains the absolute path of the node at * nodeoffset, as a NUL-terminated string. * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag * -FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1) * characters and will not fit in the given buffer. * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, standard meanings */ int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen); /** * fdt_supernode_atdepth_offset - find a specific ancestor of a node * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose parent to find * @supernodedepth: depth of the ancestor to find * @nodedepth: pointer to an integer variable (will be overwritten) or NULL * * fdt_supernode_atdepth_offset() finds an ancestor of the given node * at a specific depth from the root (where the root itself has depth * 0, its immediate subnodes depth 1 and so forth). So * fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL); * will always return 0, the offset of the root node. If the node at * nodeoffset has depth D, then: * fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL); * will return nodeoffset itself. * * NOTE: This function is expensive, as it must scan the device tree * structure from the start to nodeoffset. * * returns: * structure block offset of the node at node offset's ancestor * of depth supernodedepth (>=0), on success * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag * -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of nodeoffset * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, standard meanings */ int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset, int supernodedepth, int *nodedepth); /** * fdt_node_depth - find the depth of a given node * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose parent to find * * fdt_node_depth() finds the depth of a given node. The root node * has depth 0, its immediate subnodes depth 1 and so forth. * * NOTE: This function is expensive, as it must scan the device tree * structure from the start to nodeoffset. * * returns: * depth of the node at nodeoffset (>=0), on success * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, standard meanings */ int fdt_node_depth(const void *fdt, int nodeoffset); /** * fdt_parent_offset - find the parent of a given node * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose parent to find * * fdt_parent_offset() locates the parent node of a given node (that * is, it finds the offset of the node which contains the node at * nodeoffset as a subnode). * * NOTE: This function is expensive, as it must scan the device tree * structure from the start to nodeoffset, *twice*. * * returns: * structure block offset of the parent of the node at nodeoffset * (>=0), on success * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, standard meanings */ int fdt_parent_offset(const void *fdt, int nodeoffset); /** * fdt_node_offset_by_prop_value - find nodes with a given property value * @fdt: pointer to the device tree blob * @startoffset: only find nodes after this offset * @propname: property name to check * @propval: property value to search for * @proplen: length of the value in propval * * fdt_node_offset_by_prop_value() returns the offset of the first * node after startoffset, which has a property named propname whose * value is of length proplen and has value equal to propval; or if * startoffset is -1, the very first such node in the tree. * * To iterate through all nodes matching the criterion, the following * idiom can be used: * offset = fdt_node_offset_by_prop_value(fdt, -1, propname, * propval, proplen); * while (offset != -FDT_ERR_NOTFOUND) { * // other code here * offset = fdt_node_offset_by_prop_value(fdt, offset, propname, * propval, proplen); * } * * Note the -1 in the first call to the function, if 0 is used here * instead, the function will never locate the root node, even if it * matches the criterion. * * returns: * structure block offset of the located node (>= 0, >startoffset), * on success * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the * tree after startoffset * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, standard meanings */ int fdt_node_offset_by_prop_value(const void *fdt, int startoffset, const char *propname, const void *propval, int proplen); /** * fdt_node_offset_by_phandle - find the node with a given phandle * @fdt: pointer to the device tree blob * @phandle: phandle value * * fdt_node_offset_by_phandle() returns the offset of the node * which has the given phandle value. If there is more than one node * in the tree with the given phandle (an invalid tree), results are * undefined. * * returns: * structure block offset of the located node (>= 0), on success * -FDT_ERR_NOTFOUND, no node with that phandle exists * -FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1) * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, standard meanings */ int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle); /** * fdt_node_check_compatible: check a node's compatible property * @fdt: pointer to the device tree blob * @nodeoffset: offset of a tree node * @compatible: string to match against * * * fdt_node_check_compatible() returns 0 if the given node contains a * 'compatible' property with the given string as one of its elements, * it returns non-zero otherwise, or on error. * * returns: * 0, if the node has a 'compatible' property listing the given string * 1, if the node has a 'compatible' property, but it does not list * the given string * -FDT_ERR_NOTFOUND, if the given node has no 'compatible' property * -FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, standard meanings */ int fdt_node_check_compatible(const void *fdt, int nodeoffset, const char *compatible); /** * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value * @fdt: pointer to the device tree blob * @startoffset: only find nodes after this offset * @compatible: 'compatible' string to match against * * fdt_node_offset_by_compatible() returns the offset of the first * node after startoffset, which has a 'compatible' property which * lists the given compatible string; or if startoffset is -1, the * very first such node in the tree. * * To iterate through all nodes matching the criterion, the following * idiom can be used: * offset = fdt_node_offset_by_compatible(fdt, -1, compatible); * while (offset != -FDT_ERR_NOTFOUND) { * // other code here * offset = fdt_node_offset_by_compatible(fdt, offset, compatible); * } * * Note the -1 in the first call to the function, if 0 is used here * instead, the function will never locate the root node, even if it * matches the criterion. * * returns: * structure block offset of the located node (>= 0, >startoffset), * on success * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the * tree after startoffset * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, standard meanings */ int fdt_node_offset_by_compatible(const void *fdt, int startoffset, const char *compatible); /** * fdt_stringlist_contains - check a string list property for a string * @strlist: Property containing a list of strings to check * @listlen: Length of property * @str: String to search for * * This is a utility function provided for convenience. The list contains * one or more strings, each terminated by \0, as is found in a device tree * "compatible" property. * * @return: 1 if the string is found in the list, 0 not found, or invalid list */ int fdt_stringlist_contains(const char *strlist, int listlen, const char *str); /** * fdt_count_strings - count the number of strings in a string list * @fdt: pointer to the device tree blob * @node: offset of the node * @property: name of the property containing the string list * @return: the number of strings in the given property */ int fdt_count_strings(const void *fdt, int node, const char *property); /** * fdt_find_string - find a string in a string list and return its index * @fdt: pointer to the device tree blob * @node: offset of the node * @property: name of the property containing the string list * @string: string to look up in the string list * @return: the index of the string or negative on error */ int fdt_find_string(const void *fdt, int node, const char *property, const char *string); /** * fdt_get_string_index() - obtain the string at a given index in a string list * @fdt: pointer to the device tree blob * @node: offset of the node * @property: name of the property containing the string list * @index: index of the string to return * @output: return location for the string * @return: 0 if the string was found or a negative error code otherwise */ int fdt_get_string_index(const void *fdt, int node, const char *property, int index, const char **output); /** * fdt_get_string() - obtain the first string in a string list * @fdt: pointer to the device tree blob * @node: offset of the node * @property: name of the property containing the string list * @output: return location for the string * @return: 0 if the string was found or a negative error code otherwise * * This is a shortcut for: * * fdt_get_string_index(fdt, node, property, 0, output). */ int fdt_get_string(const void *fdt, int node, const char *property, const char **output); /**********************************************************************/ /* Read-only functions (addressing related) */ /**********************************************************************/ /** * FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells * * This is the maximum value for #address-cells, #size-cells and * similar properties that will be processed by libfdt. IEE1275 * requires that OF implementations handle values up to 4. * Implementations may support larger values, but in practice higher * values aren't used. */ #define FDT_MAX_NCELLS 4 /** * fdt_address_cells - retrieve address size for a bus represented in the tree * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node to find the address size for * * When the node has a valid #address-cells property, returns its value. * * returns: * 0 <= n < FDT_MAX_NCELLS, on success * 2, if the node has no #address-cells property * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid * #address-cells property * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_address_cells(const void *fdt, int nodeoffset); /** * fdt_size_cells - retrieve address range size for a bus represented in the * tree * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node to find the address range size for * * When the node has a valid #size-cells property, returns its value. * * returns: * 0 <= n < FDT_MAX_NCELLS, on success * 2, if the node has no #address-cells property * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid * #size-cells property * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_size_cells(const void *fdt, int nodeoffset); /**********************************************************************/ /* Write-in-place functions */ /**********************************************************************/ /** * fdt_setprop_inplace - change a property's value, but not its size * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @val: pointer to data to replace the property value with * @len: length of the property value * * fdt_setprop_inplace() replaces the value of a given property with * the data in val, of length len. This function cannot change the * size of a property, and so will only work if len is equal to the * current length of the property. * * This function will alter only the bytes in the blob which contain * the given property value, and will not alter or move any other part * of the tree. * * returns: * 0, on success * -FDT_ERR_NOSPACE, if len is not equal to the property's current length * -FDT_ERR_NOTFOUND, node does not have the named property * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name, const void *val, int len); /** * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @val: 32-bit integer value to replace the property with * * fdt_setprop_inplace_u32() replaces the value of a given property * with the 32-bit integer value in val, converting val to big-endian * if necessary. This function cannot change the size of a property, * and so will only work if the property already exists and has length * 4. * * This function will alter only the bytes in the blob which contain * the given property value, and will not alter or move any other part * of the tree. * * returns: * 0, on success * -FDT_ERR_NOSPACE, if the property's length is not equal to 4 * -FDT_ERR_NOTFOUND, node does not have the named property * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset, const char *name, uint32_t val) { fdt32_t tmp = cpu_to_fdt32(val); return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp)); } /** * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @val: 64-bit integer value to replace the property with * * fdt_setprop_inplace_u64() replaces the value of a given property * with the 64-bit integer value in val, converting val to big-endian * if necessary. This function cannot change the size of a property, * and so will only work if the property already exists and has length * 8. * * This function will alter only the bytes in the blob which contain * the given property value, and will not alter or move any other part * of the tree. * * returns: * 0, on success * -FDT_ERR_NOSPACE, if the property's length is not equal to 8 * -FDT_ERR_NOTFOUND, node does not have the named property * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset, const char *name, uint64_t val) { fdt64_t tmp = cpu_to_fdt64(val); return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp)); } /** * fdt_setprop_inplace_cell - change the value of a single-cell property * * This is an alternative name for fdt_setprop_inplace_u32() */ static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset, const char *name, uint32_t val) { return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val); } /** * fdt_nop_property - replace a property with nop tags * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to nop * @name: name of the property to nop * * fdt_nop_property() will replace a given property's representation * in the blob with FDT_NOP tags, effectively removing it from the * tree. * * This function will alter only the bytes in the blob which contain * the property, and will not alter or move any other part of the * tree. * * returns: * 0, on success * -FDT_ERR_NOTFOUND, node does not have the named property * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_nop_property(void *fdt, int nodeoffset, const char *name); /** * fdt_nop_node - replace a node (subtree) with nop tags * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node to nop * * fdt_nop_node() will replace a given node's representation in the * blob, including all its subnodes, if any, with FDT_NOP tags, * effectively removing it from the tree. * * This function will alter only the bytes in the blob which contain * the node and its properties and subnodes, and will not alter or * move any other part of the tree. * * returns: * 0, on success * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_nop_node(void *fdt, int nodeoffset); /**********************************************************************/ /* Sequential write functions */ /**********************************************************************/ int fdt_create(void *buf, int bufsize); int fdt_resize(void *fdt, void *buf, int bufsize); int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size); int fdt_finish_reservemap(void *fdt); int fdt_begin_node(void *fdt, const char *name); int fdt_property(void *fdt, const char *name, const void *val, int len); static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val) { fdt32_t tmp = cpu_to_fdt32(val); return fdt_property(fdt, name, &tmp, sizeof(tmp)); } static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val) { fdt64_t tmp = cpu_to_fdt64(val); return fdt_property(fdt, name, &tmp, sizeof(tmp)); } static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val) { return fdt_property_u32(fdt, name, val); } #define fdt_property_string(fdt, name, str) \ fdt_property(fdt, name, str, strlen(str)+1) int fdt_end_node(void *fdt); int fdt_finish(void *fdt); /**********************************************************************/ /* Read-write functions */ /**********************************************************************/ int fdt_create_empty_tree(void *buf, int bufsize); int fdt_open_into(const void *fdt, void *buf, int bufsize); int fdt_pack(void *fdt); /** * fdt_add_mem_rsv - add one memory reserve map entry * @fdt: pointer to the device tree blob * @address, @size: 64-bit values (native endian) * * Adds a reserve map entry to the given blob reserving a region at * address address of length size. * * This function will insert data into the reserve map and will * therefore change the indexes of some entries in the table. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to * contain the new reservation entry * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size); /** * fdt_del_mem_rsv - remove a memory reserve map entry * @fdt: pointer to the device tree blob * @n: entry to remove * * fdt_del_mem_rsv() removes the n-th memory reserve map entry from * the blob. * * This function will delete data from the reservation table and will * therefore change the indexes of some entries in the table. * * returns: * 0, on success * -FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there * are less than n+1 reserve map entries) * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_del_mem_rsv(void *fdt, int n); /** * fdt_set_name - change the name of a given node * @fdt: pointer to the device tree blob * @nodeoffset: structure block offset of a node * @name: name to give the node * * fdt_set_name() replaces the name (including unit address, if any) * of the given node with the given string. NOTE: this function can't * efficiently check if the new name is unique amongst the given * node's siblings; results are undefined if this function is invoked * with a name equal to one of the given node's siblings. * * This function may insert or delete data from the blob, and will * therefore change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob * to contain the new name * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, standard meanings */ int fdt_set_name(void *fdt, int nodeoffset, const char *name); /** * fdt_setprop - create or change a property * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @val: pointer to data to set the property value to * @len: length of the property value * * fdt_setprop() sets the value of the named property in the given * node to the given value and length, creating the property if it * does not already exist. * * This function may insert or delete data from the blob, and will * therefore change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to * contain the new property value * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_setprop(void *fdt, int nodeoffset, const char *name, const void *val, int len); /** * fdt_setprop_u32 - set a property to a 32-bit integer * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @val: 32-bit integer value for the property (native endian) * * fdt_setprop_u32() sets the value of the named property in the given * node to the given 32-bit integer value (converting to big-endian if * necessary), or creates a new property with that value if it does * not already exist. * * This function may insert or delete data from the blob, and will * therefore change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to * contain the new property value * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name, uint32_t val) { fdt32_t tmp = cpu_to_fdt32(val); return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp)); } /** * fdt_setprop_u64 - set a property to a 64-bit integer * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @val: 64-bit integer value for the property (native endian) * * fdt_setprop_u64() sets the value of the named property in the given * node to the given 64-bit integer value (converting to big-endian if * necessary), or creates a new property with that value if it does * not already exist. * * This function may insert or delete data from the blob, and will * therefore change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to * contain the new property value * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name, uint64_t val) { fdt64_t tmp = cpu_to_fdt64(val); return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp)); } /** * fdt_setprop_cell - set a property to a single cell value * * This is an alternative name for fdt_setprop_u32() */ static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name, uint32_t val) { return fdt_setprop_u32(fdt, nodeoffset, name, val); } /** * fdt_setprop_string - set a property to a string value * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @str: string value for the property * * fdt_setprop_string() sets the value of the named property in the * given node to the given string value (using the length of the * string to determine the new length of the property), or creates a * new property with that value if it does not already exist. * * This function may insert or delete data from the blob, and will * therefore change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to * contain the new property value * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ #define fdt_setprop_string(fdt, nodeoffset, name, str) \ fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1) /** * fdt_appendprop - append to or create a property * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to append to * @val: pointer to data to append to the property value * @len: length of the data to append to the property value * * fdt_appendprop() appends the value to the named property in the * given node, creating the property if it does not already exist. * * This function may insert data into the blob, and will therefore * change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to * contain the new property value * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_appendprop(void *fdt, int nodeoffset, const char *name, const void *val, int len); /** * fdt_appendprop_u32 - append a 32-bit integer value to a property * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @val: 32-bit integer value to append to the property (native endian) * * fdt_appendprop_u32() appends the given 32-bit integer value * (converting to big-endian if necessary) to the value of the named * property in the given node, or creates a new property with that * value if it does not already exist. * * This function may insert data into the blob, and will therefore * change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to * contain the new property value * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ static inline int fdt_appendprop_u32(void *fdt, int nodeoffset, const char *name, uint32_t val) { fdt32_t tmp = cpu_to_fdt32(val); return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp)); } /** * fdt_appendprop_u64 - append a 64-bit integer value to a property * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @val: 64-bit integer value to append to the property (native endian) * * fdt_appendprop_u64() appends the given 64-bit integer value * (converting to big-endian if necessary) to the value of the named * property in the given node, or creates a new property with that * value if it does not already exist. * * This function may insert data into the blob, and will therefore * change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to * contain the new property value * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ static inline int fdt_appendprop_u64(void *fdt, int nodeoffset, const char *name, uint64_t val) { fdt64_t tmp = cpu_to_fdt64(val); return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp)); } /** * fdt_appendprop_cell - append a single cell value to a property * * This is an alternative name for fdt_appendprop_u32() */ static inline int fdt_appendprop_cell(void *fdt, int nodeoffset, const char *name, uint32_t val) { return fdt_appendprop_u32(fdt, nodeoffset, name, val); } /** * fdt_appendprop_string - append a string to a property * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @str: string value to append to the property * * fdt_appendprop_string() appends the given string to the value of * the named property in the given node, or creates a new property * with that value if it does not already exist. * * This function may insert data into the blob, and will therefore * change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to * contain the new property value * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ #define fdt_appendprop_string(fdt, nodeoffset, name, str) \ fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1) /** * fdt_delprop - delete a property * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to nop * @name: name of the property to nop * * fdt_del_property() will delete the given property. * * This function will delete data from the blob, and will therefore * change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOTFOUND, node does not have the named property * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_delprop(void *fdt, int nodeoffset, const char *name); /** * fdt_add_subnode_namelen - creates a new node based on substring * @fdt: pointer to the device tree blob * @parentoffset: structure block offset of a node * @name: name of the subnode to locate * @namelen: number of characters of name to consider * * Identical to fdt_add_subnode(), but use only the first namelen * characters of name as the name of the new node. This is useful for * creating subnodes based on a portion of a larger string, such as a * full path. */ int fdt_add_subnode_namelen(void *fdt, int parentoffset, const char *name, int namelen); /** * fdt_add_subnode - creates a new node * @fdt: pointer to the device tree blob * @parentoffset: structure block offset of a node * @name: name of the subnode to locate * * fdt_add_subnode() creates a new node as a subnode of the node at * structure block offset parentoffset, with the given name (which * should include the unit address, if any). * * This function will insert data into the blob, and will therefore * change the offsets of some existing nodes. * returns: * structure block offset of the created nodeequested subnode (>=0), on success * -FDT_ERR_NOTFOUND, if the requested subnode does not exist * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag * -FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of * the given name * -FDT_ERR_NOSPACE, if there is insufficient free space in the * blob to contain the new node * -FDT_ERR_NOSPACE * -FDT_ERR_BADLAYOUT * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings. */ int fdt_add_subnode(void *fdt, int parentoffset, const char *name); /** * fdt_del_node - delete a node (subtree) * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node to nop * * fdt_del_node() will remove the given node, including all its * subnodes if any, from the blob. * * This function will delete data from the blob, and will therefore * change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_del_node(void *fdt, int nodeoffset); /**********************************************************************/ /* Debugging / informational functions */ /**********************************************************************/ const char *fdt_strerror(int errval); /** * fdt_remove_unused_strings() - Remove any unused strings from an FDT * * This creates a new device tree in @new with unused strings removed. The * called can then use fdt_pack() to minimise the space consumed. * * @old: Old device tree blog * @new: Place to put new device tree blob, which must be as large as * @old * @return * 0, on success * -FDT_ERR_BADOFFSET, corrupt device tree * -FDT_ERR_NOSPACE, out of space, which should not happen unless there * is something very wrong with the device tree input */ int fdt_remove_unused_strings(const void *old, void *new); struct fdt_region { int offset; int size; }; /* * Flags for fdt_find_regions() * * Add a region for the string table (always the last region) */ #define FDT_REG_ADD_STRING_TAB (1 << 0) /* * Add all supernodes of a matching node/property, useful for creating a * valid subset tree */ #define FDT_REG_SUPERNODES (1 << 1) /* Add the FDT_BEGIN_NODE tags of subnodes, including their names */ #define FDT_REG_DIRECT_SUBNODES (1 << 2) /* Add all subnodes of a matching node */ #define FDT_REG_ALL_SUBNODES (1 << 3) /* Add a region for the mem_rsvmap table (always the first region) */ #define FDT_REG_ADD_MEM_RSVMAP (1 << 4) /* Indicates what an fdt part is (node, property, value) */ #define FDT_IS_NODE (1 << 0) #define FDT_IS_PROP (1 << 1) #define FDT_IS_VALUE (1 << 2) /* not supported */ #define FDT_IS_COMPAT (1 << 3) /* used internally */ #define FDT_NODE_HAS_PROP (1 << 4) /* node contains prop */ #define FDT_ANY_GLOBAL (FDT_IS_NODE | FDT_IS_PROP | FDT_IS_VALUE | \ FDT_IS_COMPAT) #define FDT_IS_ANY 0x1f /* all the above */ /* We set a reasonable limit on the number of nested nodes */ #define FDT_MAX_DEPTH 32 /* Decribes what we want to include from the current tag */ enum want_t { WANT_NOTHING, WANT_NODES_ONLY, /* No properties */ WANT_NODES_AND_PROPS, /* Everything for one level */ WANT_ALL_NODES_AND_PROPS /* Everything for all levels */ }; /* Keeps track of the state at parent nodes */ struct fdt_subnode_stack { int offset; /* Offset of node */ enum want_t want; /* The 'want' value here */ int included; /* 1 if we included this node, 0 if not */ }; struct fdt_region_ptrs { int depth; /* Current tree depth */ int done; /* What we have completed scanning */ enum want_t want; /* What we are currently including */ char *end; /* Pointer to end of full node path */ int nextoffset; /* Next node offset to check */ }; /* The state of our finding algortihm */ struct fdt_region_state { struct fdt_subnode_stack stack[FDT_MAX_DEPTH]; /* node stack */ struct fdt_region *region; /* Contains list of regions found */ int count; /* Numnber of regions found */ const void *fdt; /* FDT blob */ int max_regions; /* Maximum regions to find */ int can_merge; /* 1 if we can merge with previous region */ int start; /* Start position of current region */ struct fdt_region_ptrs ptrs; /* Pointers for what we are up to */ }; /** * fdt_find_regions() - find regions in device tree * * Given a list of nodes to include and properties to exclude, find * the regions of the device tree which describe those included parts. * * The intent is to get a list of regions which will be invariant provided * those parts are invariant. For example, if you request a list of regions * for all nodes but exclude the property "data", then you will get the * same region contents regardless of any change to "data" properties. * * This function can be used to produce a byte-stream to send to a hashing * function to verify that critical parts of the FDT have not changed. * * Nodes which are given in 'inc' are included in the region list, as * are the names of the immediate subnodes nodes (but not the properties * or subnodes of those subnodes). * * For eaxample "/" means to include the root node, all root properties * and the FDT_BEGIN_NODE and FDT_END_NODE of all subnodes of /. The latter * ensures that we capture the names of the subnodes. In a hashing situation * it prevents the root node from changing at all Any change to non-excluded * properties, names of subnodes or number of subnodes would be detected. * * When used with FITs this provides the ability to hash and sign parts of * the FIT based on different configurations in the FIT. Then it is * impossible to change anything about that configuration (include images * attached to the configuration), but it may be possible to add new * configurations, new images or new signatures within the existing * framework. * * Adding new properties to a device tree may result in the string table * being extended (if the new property names are different from those * already added). This function can optionally include a region for * the string table so that this can be part of the hash too. * * The device tree header is not included in the list. * * @fdt: Device tree to check * @inc: List of node paths to included * @inc_count: Number of node paths in list * @exc_prop: List of properties names to exclude * @exc_prop_count: Number of properties in exclude list * @region: Returns list of regions * @max_region: Maximum length of region list * @path: Pointer to a temporary string for the function to use for * building path names * @path_len: Length of path, must be large enough to hold the longest * path in the tree * @add_string_tab: 1 to add a region for the string table * @return number of regions in list. If this is >max_regions then the * region array was exhausted. You should increase max_regions and try * the call again. */ int fdt_find_regions(const void *fdt, char * const inc[], int inc_count, char * const exc_prop[], int exc_prop_count, struct fdt_region region[], int max_regions, char *path, int path_len, int add_string_tab); /** * fdt_first_region() - find regions in device tree * * Given a nodes and properties to include and properties to exclude, find * the regions of the device tree which describe those included parts. * * The use for this function is twofold. Firstly it provides a convenient * way of performing a structure-aware grep of the tree. For example it is * possible to grep for a node and get all the properties associated with * that node. Trees can be subsetted easily, by specifying the nodes that * are required, and then writing out the regions returned by this function. * This is useful for small resource-constrained systems, such as boot * loaders, which want to use an FDT but do not need to know about all of * it. * * Secondly it makes it easy to hash parts of the tree and detect changes. * The intent is to get a list of regions which will be invariant provided * those parts are invariant. For example, if you request a list of regions * for all nodes but exclude the property "data", then you will get the * same region contents regardless of any change to "data" properties. * * This function can be used to produce a byte-stream to send to a hashing * function to verify that critical parts of the FDT have not changed. * Note that semantically null changes in order could still cause false * hash misses. Such reordering might happen if the tree is regenerated * from source, and nodes are reordered (the bytes-stream will be emitted * in a different order and mnay hash functions will detect this). However * if an existing tree is modified using libfdt functions, such as * fdt_add_subnode() and fdt_setprop(), then this problem is avoided. * * The nodes/properties to include/exclude are defined by a function * provided by the caller. This function is called for each node and * property, and must return: * * 0 - to exclude this part * 1 - to include this part * -1 - for FDT_IS_PROP only: no information is available, so include * if its containing node is included * * The last case is only used to deal with properties. Often a property is * included if its containing node is included - this is the case where * -1 is returned.. However if the property is specifically required to be * included/excluded, then 0 or 1 can be returned. Note that including a * property when the FDT_REG_SUPERNODES flag is given will force its * containing node to be included since it is not valid to have a property * that is not in a node. * * Using the information provided, the inclusion of a node can be controlled * either by a node name or its compatible string, or any other property * that the function can determine. * * As an example, including node "/" means to include the root node and all * root properties. A flag provides a way of also including supernodes (of * which there is none for the root node), and another flag includes * immediate subnodes, so in this case we would get the FDT_BEGIN_NODE and * FDT_END_NODE of all subnodes of /. * * The subnode feature helps in a hashing situation since it prevents the * root node from changing at all. Any change to non-excluded properties, * names of subnodes or number of subnodes would be detected. * * When used with FITs this provides the ability to hash and sign parts of * the FIT based on different configurations in the FIT. Then it is * impossible to change anything about that configuration (include images * attached to the configuration), but it may be possible to add new * configurations, new images or new signatures within the existing * framework. * * Adding new properties to a device tree may result in the string table * being extended (if the new property names are different from those * already added). This function can optionally include a region for * the string table so that this can be part of the hash too. This is always * the last region. * * The FDT also has a mem_rsvmap table which can also be included, and is * always the first region if so. * * The device tree header is not included in the region list. Since the * contents of the FDT are changing (shrinking, often), the caller will need * to regenerate the header anyway. * * @fdt: Device tree to check * @h_include: Function to call to determine whether to include a part or * not: * * @priv: Private pointer as passed to fdt_find_regions() * @fdt: Pointer to FDT blob * @offset: Offset of this node / property * @type: Type of this part, FDT_IS_... * @data: Pointer to data (node name, property name, compatible * string, value (not yet supported) * @size: Size of data, or 0 if none * @return 0 to exclude, 1 to include, -1 if no information is * available * @priv: Private pointer passed to h_include * @region: Returns list of regions, sorted by offset * @max_regions: Maximum length of region list * @path: Pointer to a temporary string for the function to use for * building path names * @path_len: Length of path, must be large enough to hold the longest * path in the tree * @flags: Various flags that control the region algortihm, see * FDT_REG_... * @return number of regions in list. If this is >max_regions then the * region array was exhausted. You should increase max_regions and try * the call again. Only the first max_regions elements are available in the * array. * * On error a -ve value is return, which can be: * * -FDT_ERR_BADSTRUCTURE (too deep or more END tags than BEGIN tags * -FDT_ERR_BADLAYOUT * -FDT_ERR_NOSPACE (path area is too small) */ int fdt_first_region(const void *fdt, int (*h_include)(void *priv, const void *fdt, int offset, int type, const char *data, int size), void *priv, struct fdt_region *region, char *path, int path_len, int flags, struct fdt_region_state *info); /** fdt_next_region() - find next region * * See fdt_first_region() for full description. This function finds the * next region according to the provided parameters, which must be the same * as passed to fdt_first_region(). * * This function can additionally return -FDT_ERR_NOTFOUND when there are no * more regions */ int fdt_next_region(const void *fdt, int (*h_include)(void *priv, const void *fdt, int offset, int type, const char *data, int size), void *priv, struct fdt_region *region, char *path, int path_len, int flags, struct fdt_region_state *info); /** * fdt_add_alias_regions() - find aliases that point to existing regions * * Once a device tree grep is complete some of the nodes will be present * and some will have been dropped. This function checks all the alias nodes * to figure out which points point to nodes which are still present. These * aliases need to be kept, along with the nodes they reference. * * Given a list of regions function finds the aliases that still apply and * adds more regions to the list for these. This function is called after * fdt_next_region() has finished returning regions and requires the same * state. * * @fdt: Device tree file to reference * @region: List of regions that will be kept * @count: Number of regions * @max_regions: Number of entries that can fit in @region * @info: Region state as returned from fdt_next_region() * @return new number of regions in @region (i.e. count + the number added) * or -FDT_ERR_NOSPACE if there was not enough space. */ int fdt_add_alias_regions(const void *fdt, struct fdt_region *region, int count, int max_regions, struct fdt_region_state *info); #endif /* _LIBFDT_H */