#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 #include #define FDT_FIRST_SUPPORTED_VERSION 0x10 #define FDT_LAST_SUPPORTED_VERSION 0x11 /* Error codes: informative error codes */ #define FDT_ERR_NOTFOUND 1 /* FDT_ERR_NOTFOUND: The requested node or property does not exist */ #define FDT_ERR_EXISTS 2 /* FDT_ERR_EXISTS: Attemped to create a node or property which * already exists */ #define FDT_ERR_NOSPACE 3 /* FDT_ERR_NOSPACE: Operation needed to expand the device * tree, but its buffer did not have sufficient space to * contain the expanded tree. Use fdt_open_into() to move the * device tree to a buffer with more space. */ /* Error codes: codes for bad parameters */ #define FDT_ERR_BADOFFSET 4 /* FDT_ERR_BADOFFSET: Function was passed a structure block * offset which is out-of-bounds, or which points to an * unsuitable part of the structure for the operation. */ #define FDT_ERR_BADPATH 5 /* FDT_ERR_BADPATH: Function was passed a badly formatted path * (e.g. missing a leading / for a function which requires an * absolute path) */ #define FDT_ERR_BADPHANDLE 6 /* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle * value. phandle values of 0 and -1 are not permitted. */ #define FDT_ERR_BADSTATE 7 /* FDT_ERR_BADSTATE: Function was passed an incomplete device * tree created by the sequential-write functions, which is * not sufficiently complete for the requested operation. */ /* Error codes: codes for bad device tree blobs */ #define FDT_ERR_TRUNCATED 8 /* FDT_ERR_TRUNCATED: Structure block of the given device tree * ends without an FDT_END tag. */ #define FDT_ERR_BADMAGIC 9 /* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a * device tree at all - it is missing the flattened device * tree magic number. */ #define FDT_ERR_BADVERSION 10 /* FDT_ERR_BADVERSION: Given device tree has a version which * can't be handled by the requested operation. For * read-write functions, this may mean that fdt_open_into() is * required to convert the tree to the expected version. */ #define FDT_ERR_BADSTRUCTURE 11 /* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt * structure block or other serious error (e.g. misnested * nodes, or subnodes preceding properties). */ #define FDT_ERR_BADLAYOUT 12 /* FDT_ERR_BADLAYOUT: For read-write functions, the given * device tree has it's sub-blocks in an order that the * function can't handle (memory reserve map, then structure, * then strings). Use fdt_open_into() to reorganize the tree * into a form suitable for the read-write operations. */ /* "Can't happen" error indicating a bug in libfdt */ #define FDT_ERR_INTERNAL 13 /* FDT_ERR_INTERNAL: libfdt has failed an internal assertion. * Should never be returned, if it is, it indicates a bug in * libfdt itself. */ #define FDT_ERR_MAX 13 /**********************************************************************/ /* Low-level functions (you probably don't need these) */ /**********************************************************************/ const void *fdt_offset_ptr (const void *fdt, int offset, 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); /**********************************************************************/ /* 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', of 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); /**********************************************************************/ /* Write-in-place functions */ /**********************************************************************/ /** * fdt_setprop_inplace - change a property's value, but not its size * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @val: pointer to data to replace the property value with * @len: length of the property value * * fdt_setprop_inplace() replaces the value of a given property with * the data in val, of length len. This function cannot change the * size of a property, and so will only work if len is equal to the * current length of the property. * * This function will alter only the bytes in the blob which contain * the given property value, and will not alter or move any other part * of the tree. * * returns: * 0, on success * -FDT_ERR_NOSPACE, if len is not equal to the property's current length * -FDT_ERR_NOTFOUND, node does not have the named property * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_setprop_inplace (void *fdt, int nodeoffset, const char *name, const void *val, int len); /** * fdt_setprop_inplace_cell - change the value of a single-cell property * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @val: cell (32-bit integer) value to replace the property with * * fdt_setprop_inplace_cell() replaces the value of a given property * with the 32-bit integer cell value in val, converting val to * big-endian if necessary. This function cannot change the size of a * property, and so will only work if the property already exists and * has length 4. * * This function will alter only the bytes in the blob which contain * the given property value, and will not alter or move any other part * of the tree. * * returns: * 0, on success * -FDT_ERR_NOSPACE, if the property's length is not equal to 4 * -FDT_ERR_NOTFOUND, node does not have the named property * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ static inline int fdt_setprop_inplace_cell (void *fdt, int nodeoffset, const char *name, uint32_t val) { val = cpu_to_fdt32 (val); return fdt_setprop_inplace (fdt, nodeoffset, name, &val, sizeof (val)); } /** * fdt_nop_property - replace a property with nop tags * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to nop * @name: name of the property to nop * * fdt_nop_property() will replace a given property's representation * in the blob with FDT_NOP tags, effectively removing it from the * tree. * * This function will alter only the bytes in the blob which contain * the property, and will not alter or move any other part of the * tree. * * returns: * 0, on success * -FDT_ERR_NOTFOUND, node does not have the named property * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_nop_property (void *fdt, int nodeoffset, const char *name); /** * fdt_nop_node - replace a node (subtree) with nop tags * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node to nop * * fdt_nop_node() will replace a given node's representation in the * blob, including all its subnodes, if any, with FDT_NOP tags, * effectively removing it from the tree. * * This function will alter only the bytes in the blob which contain * the node and its properties and subnodes, and will not alter or * move any other part of the tree. * * returns: * 0, on success * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_nop_node (void *fdt, int nodeoffset); /**********************************************************************/ /* Sequential write functions */ /**********************************************************************/ int fdt_create (void *buf, int bufsize); int fdt_add_reservemap_entry (void *fdt, uint64_t addr, uint64_t size); int fdt_finish_reservemap (void *fdt); int fdt_begin_node (void *fdt, const char *name); int fdt_property (void *fdt, const char *name, const void *val, int len); static inline int fdt_property_cell (void *fdt, const char *name, uint32_t val) { val = cpu_to_fdt32 (val); return fdt_property (fdt, name, &val, sizeof (val)); } #define fdt_property_string(fdt, name, str) \ fdt_property(fdt, name, str, strlen(str)+1) int fdt_end_node (void *fdt); int fdt_finish (void *fdt); /**********************************************************************/ /* Read-write functions */ /**********************************************************************/ int fdt_open_into (const void *fdt, void *buf, int bufsize); int fdt_pack (void *fdt); /** * fdt_add_mem_rsv - add one memory reserve map entry * @fdt: pointer to the device tree blob * @address, @size: 64-bit values (native endian) * * Adds a reserve map entry to the given blob reserving a region at * address address of length size. * * This function will insert data into the reserve map and will * therefore change the indexes of some entries in the table. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to * contain the new reservation entry * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_add_mem_rsv (void *fdt, uint64_t address, uint64_t size); /** * fdt_del_mem_rsv - remove a memory reserve map entry * @fdt: pointer to the device tree blob * @n: entry to remove * * fdt_del_mem_rsv() removes the n-th memory reserve map entry from * the blob. * * This function will delete data from the reservation table and will * therefore change the indexes of some entries in the table. * * returns: * 0, on success * -FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there * are less than n+1 reserve map entries) * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_del_mem_rsv (void *fdt, int n); /** * fdt_set_name - change the name of a given node * @fdt: pointer to the device tree blob * @nodeoffset: structure block offset of a node * @name: name to give the node * * fdt_set_name() replaces the name (including unit address, if any) * of the given node with the given string. NOTE: this function can't * efficiently check if the new name is unique amongst the given * node's siblings; results are undefined if this function is invoked * with a name equal to one of the given node's siblings. * * This function may insert or delete data from the blob, and will * therefore change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob * to contain the new name * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, standard meanings */ int fdt_set_name (void *fdt, int nodeoffset, const char *name); /** * fdt_setprop - create or change a property * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @val: pointer to data to set the property value to * @len: length of the property value * * fdt_setprop() sets the value of the named property in the given * node to the given value and length, creating the property if it * does not already exist. * * This function may insert or delete data from the blob, and will * therefore change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to * contain the new property value * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_setprop (void *fdt, int nodeoffset, const char *name, const void *val, int len); /** * fdt_setprop_cell - set a property to a single cell value * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @val: 32-bit integer value for the property (native endian) * * fdt_setprop_cell() sets the value of the named property in the * given node to the given cell value (converting to big-endian if * necessary), or creates a new property with that value if it does * not already exist. * * This function may insert or delete data from the blob, and will * therefore change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to * contain the new property value * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ static inline int fdt_setprop_cell (void *fdt, int nodeoffset, const char *name, uint32_t val) { val = cpu_to_fdt32 (val); return fdt_setprop (fdt, nodeoffset, name, &val, sizeof (val)); } /** * fdt_setprop_string - set a property to a string value * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to change * @name: name of the property to change * @str: string value for the property * * fdt_setprop_string() sets the value of the named property in the * given node to the given string value (using the length of the * string to determine the new length of the property), or creates a * new property with that value if it does not already exist. * * This function may insert or delete data from the blob, and will * therefore change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to * contain the new property value * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_BADLAYOUT, * -FDT_ERR_TRUNCATED, standard meanings */ #define fdt_setprop_string(fdt, nodeoffset, name, str) \ fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1) /** * fdt_delprop - delete a property * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node whose property to nop * @name: name of the property to nop * * fdt_del_property() will delete the given property. * * This function will delete data from the blob, and will therefore * change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_NOTFOUND, node does not have the named property * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_delprop (void *fdt, int nodeoffset, const char *name); /** * fdt_add_subnode_namelen - creates a new node based on substring * @fdt: pointer to the device tree blob * @parentoffset: structure block offset of a node * @name: name of the subnode to locate * @namelen: number of characters of name to consider * * Identical to fdt_add_subnode(), but use only the first namelen * characters of name as the name of the new node. This is useful for * creating subnodes based on a portion of a larger string, such as a * full path. */ int fdt_add_subnode_namelen (void *fdt, int parentoffset, const char *name, int namelen); /** * fdt_add_subnode - creates a new node * @fdt: pointer to the device tree blob * @parentoffset: structure block offset of a node * @name: name of the subnode to locate * * fdt_add_subnode() creates a new node as a subnode of the node at * structure block offset parentoffset, with the given name (which * should include the unit address, if any). * * This function will insert data into the blob, and will therefore * change the offsets of some existing nodes. * returns: * structure block offset of the created nodeequested subnode (>=0), on success * -FDT_ERR_NOTFOUND, if the requested subnode does not exist * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag * -FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of * the given name * -FDT_ERR_NOSPACE, if there is insufficient free space in the * blob to contain the new node * -FDT_ERR_NOSPACE * -FDT_ERR_BADLAYOUT * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings. */ int fdt_add_subnode (void *fdt, int parentoffset, const char *name); /** * fdt_del_node - delete a node (subtree) * @fdt: pointer to the device tree blob * @nodeoffset: offset of the node to nop * * fdt_del_node() will remove the given node, including all its * subnodes if any, from the blob. * * This function will delete data from the blob, and will therefore * change the offsets of some existing nodes. * * returns: * 0, on success * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag * -FDT_ERR_BADLAYOUT, * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings */ int fdt_del_node (void *fdt, int nodeoffset); /**********************************************************************/ /* Debugging / informational functions */ /**********************************************************************/ const char *fdt_strerror (int errval); #endif /* _LIBFDT_H */