#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_BADSTATE 6 /* FDT_ERR_BADSTATE: Function was passed an incomplete device * tree created by the sequential-write functions, which is * not sufficiently complete for the requested operation. */ /* Error codes: codes for bad device tree blobs */ #define FDT_ERR_TRUNCATED 7 /* FDT_ERR_TRUNCATED: Structure block of the given device tree * ends without an FDT_END tag. */ #define FDT_ERR_BADMAGIC 8 /* 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 9 /* 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 10 /* 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 11 /* 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 12 /* FDT_ERR_INTERNAL: libfdt has failed an internal assertion. * Indicates a bug in libfdt itself. */ #define FDT_ERR_MAX 12 /**********************************************************************/ /* Low-level functions (you probably don't need these) */ /**********************************************************************/ const void *fdt_offset_ptr(const void *fdt, int offset, int checklen); static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen) { return (void *)fdt_offset_ptr(fdt, offset, checklen); } #define fdt_offset_ptr_typed(fdt, offset, var) \ ((typeof(var))(fdt_offset_ptr((fdt), (offset), sizeof(*(var))))) #define fdt_offset_ptr_typed_w(fdt, offset, var) \ ((typeof(var))(fdt_offset_ptr_w((fdt), (offset), sizeof(*(var))))) uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset); /**********************************************************************/ /* General functions */ /**********************************************************************/ #define fdt_get_header(fdt, field) \ (fdt32_to_cpu(((const struct fdt_header *)(fdt))->field)) #define fdt_magic(fdt) (fdt_get_header(fdt, magic)) #define fdt_totalsize(fdt) (fdt_get_header(fdt, totalsize)) #define fdt_off_dt_struct(fdt) (fdt_get_header(fdt, off_dt_struct)) #define fdt_off_dt_strings(fdt) (fdt_get_header(fdt, off_dt_strings)) #define fdt_off_mem_rsvmap(fdt) (fdt_get_header(fdt, off_mem_rsvmap)) #define fdt_version(fdt) (fdt_get_header(fdt, version)) #define fdt_last_comp_version(fdt) (fdt_get_header(fdt, last_comp_version)) #define fdt_boot_cpuid_phys(fdt) (fdt_get_header(fdt, boot_cpuid_phys)) #define fdt_size_dt_strings(fdt) (fdt_get_header(fdt, size_dt_strings)) #define fdt_size_dt_struct(fdt) (fdt_get_header(fdt, size_dt_struct)) #define __fdt_set_hdr(name) \ static inline void fdt_set_##name(void *fdt, uint32_t val) \ { \ struct fdt_header *fdth = fdt; \ fdth->name = cpu_to_fdt32(val); \ } __fdt_set_hdr(magic); __fdt_set_hdr(totalsize); __fdt_set_hdr(off_dt_struct); __fdt_set_hdr(off_dt_strings); __fdt_set_hdr(off_mem_rsvmap); __fdt_set_hdr(version); __fdt_set_hdr(last_comp_version); __fdt_set_hdr(boot_cpuid_phys); __fdt_set_hdr(size_dt_strings); __fdt_set_hdr(size_dt_struct); #undef __fdt_set_hdr /** * fdt_check_header - sanity check a device tree or possible device tree * @fdt: pointer to data which might be a flattened device tree * * fdt_check_header() checks that the given buffer contains what * appears to be a flattened device tree with sane information in its * header. * * returns: * 0, if the buffer appears to contain a valid device tree * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, standard meanings, as above */ int fdt_check_header(const void *fdt); /** * fdt_move - move a device tree around in memory * @fdt: pointer to the device tree to move * @buf: pointer to memory where the device is to be moved * @bufsize: size of the memory space at buf * * fdt_move() relocates, if possible, the device tree blob located at * fdt to the buffer at buf of size bufsize. The buffer may overlap * with the existing device tree blob at fdt. Therefore, * fdt_move(fdt, fdt, fdt_totalsize(fdt)) * should always succeed. * * returns: * 0, on success * -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, standard meanings */ int fdt_move(const void *fdt, void *buf, int bufsize); /**********************************************************************/ /* Read-only functions */ /**********************************************************************/ /** * fdt_string - retreive a string from the strings block of a device tree * @fdt: pointer to the device tree blob * @stroffset: offset of the string within the strings block (native endian) * * fdt_string() retrieves a pointer to a single string from the * strings block of the device tree blob at fdt. * * returns: * a pointer to the string, on success * NULL, if stroffset is out of bounds */ const char *fdt_string(const void *fdt, int stroffset); /** * fdt_num_mem_rsv - retreive the number of memory reserve map entries * @fdt: pointer to the device tree blob * * Returns the number of entries in the device tree blob's memory * reservation map. This does not include the terminating 0,0 entry * or any other (0,0) entries reserved for expansion. * * returns: * the number of entries */ int fdt_num_mem_rsv(const void *fdt); /** * fdt_get_mem_rsv - retreive one memory reserve map entry * @fdt: pointer to the device tree blob * @address, @size: pointers to 64-bit variables * * On success, *address and *size will contain the address and size of * the n-th reserve map entry from the device tree blob, in * native-endian format. * * returns: * 0, on success * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, standard meanings */ int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size); /** * fdt_subnode_offset_namelen - find a subnode based on substring * @fdt: pointer to the device tree blob * @parentoffset: structure block offset of a node * @name: name of the subnode to locate * @namelen: number of characters of name to consider * * Identical to fdt_subnode_offset(), but only examine the first * namelen characters of name for matching the subnode name. This is * useful for finding subnodes based on a portion of a larger string, * such as a full path. */ int fdt_subnode_offset_namelen(const void *fdt, int parentoffset, const char *name, int namelen); /** * fdt_subnode_offset - find a subnode of a given node * @fdt: pointer to the device tree blob * @parentoffset: structure block offset of a node * @name: name of the subnode to locate * * fdt_subnode_offset() finds a subnode of the node at structure block * offset parentoffset with the given name. name may include a unit * address, in which case fdt_subnode_offset() will find the subnode * with that unit address, or the unit address may be omitted, in * which case fdt_subnode_offset() will find an arbitrary subnode * whose name excluding unit address matches the given name. * * returns: * structure block offset of the requested subnode (>=0), on success * -FDT_ERR_NOTFOUND, if the requested subnode does not exist * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings. */ int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name); /** * fdt_path_offset - find a tree node by its full path * @fdt: pointer to the device tree blob * @path: full path of the node to locate * * fdt_path_offset() finds a node of a given path in the device tree. * Each path component may omit the unit address portion, but the * results of this are undefined if any such path component is * ambiguous (that is if there are multiple nodes at the relevant * level matching the given component, differentiated only by unit * address). * * returns: * structure block offset of the node with the requested path (>=0), on success * -FDT_ERR_BADPATH, given path does not begin with '/' or is invalid * -FDT_ERR_NOTFOUND, if the requested node does not exist * -FDT_ERR_BADMAGIC, * -FDT_ERR_BADVERSION, * -FDT_ERR_BADSTATE, * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings. */ int fdt_path_offset(const void *fdt, const char *path); /** * fdt_get_name - retreive the name of a given node * @fdt: pointer to the device tree blob * @nodeoffset: structure block offset of the starting node * @len: pointer to an intger 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 len is * non-NULL, the length of this name is also returned, in the integer * pointed to by len. * * returns: * pointer to the node's name, on success * *len contains the length of that name (>=0) * NULL, on error * *len 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 *len); const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset, const char *name, int *lenp); static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset, const char *name, int *lenp) { return (struct fdt_property *)fdt_get_property(fdt, nodeoffset, name, lenp); } const void *fdt_getprop(const void *fdt, int nodeoffset, const char *name, int *lenp); static inline void *fdt_getprop_w(void *fdt, int nodeoffset, const char *name, int *lenp) { return (void *)fdt_getprop(fdt, nodeoffset, name, lenp); } int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen); int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset, int supernodedepth, int *nodedepth); int fdt_node_depth(const void *fdt, int nodeoffset); int fdt_parent_offset(const void *fdt, int nodeoffset); int fdt_node_offset_by_prop_value(const void *fdt, int startoffset, const char *propname, const void *propval, int proplen); int fdt_node_check_compatible(const void *fdt, int nodeoffset, const char *compatible); int fdt_node_offset_by_compatible(const void *fdt, int startoffset, const char *compatible); /**********************************************************************/ /* Write-in-place functions */ /**********************************************************************/ int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name, const void *val, int len); #define fdt_setprop_inplace_typed(fdt, nodeoffset, name, val) \ ({ \ typeof(val) x = val; \ fdt_setprop_inplace(fdt, nodeoffset, name, &x, sizeof(x)); \ }) int fdt_nop_property(void *fdt, int nodeoffset, const char *name); int fdt_nop_node(void *fdt, int nodeoffset); /**********************************************************************/ /* Sequential write functions */ /**********************************************************************/ int fdt_create(void *buf, int bufsize); int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size); int fdt_finish_reservemap(void *fdt); int fdt_begin_node(void *fdt, const char *name); int fdt_property(void *fdt, const char *name, const void *val, int len); #define fdt_property_typed(fdt, name, val) \ ({ \ typeof(val) x = (val); \ fdt_property((fdt), (name), &x, sizeof(x)); \ }) #define fdt_property_string(fdt, name, str) \ fdt_property(fdt, name, str, strlen(str)+1) int fdt_end_node(void *fdt); int fdt_finish(void *fdt); /**********************************************************************/ /* Read-write functions */ /**********************************************************************/ int fdt_open_into(const void *fdt, void *buf, int bufsize); int fdt_pack(void *fdt); int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size); int fdt_del_mem_rsv(void *fdt, int n); int fdt_setprop(void *fdt, int nodeoffset, const char *name, const void *val, int len); #define fdt_setprop_typed(fdt, nodeoffset, name, val) \ ({ \ typeof(val) x = (val); \ fdt_setprop((fdt), (nodeoffset), (name), &x, sizeof(x)); \ }) #define fdt_setprop_string(fdt, nodeoffset, name, str) \ fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1) int fdt_delprop(void *fdt, int nodeoffset, const char *name); int fdt_add_subnode_namelen(void *fdt, int parentoffset, const char *name, int namelen); int fdt_add_subnode(void *fdt, int parentoffset, const char *name); int fdt_del_node(void *fdt, int nodeoffset); /**********************************************************************/ /* Debugging / informational functions */ /**********************************************************************/ const char *fdt_strerror(int errval); #endif /* _LIBFDT_H */