X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;ds=sidebyside;f=include%2Flibfdt.h;h=765d84f5e4574eaab187be553cdbd449bf22b819;hb=b37c4a2baabc61450bb9f8bd16b233a25315c816;hp=fc7f75b9ffa60b6bc23f44d39b59c4d0f4b7be3b;hpb=b2ba62a1aa7f2b68c418cf44ab15eee718913272;p=u-boot diff --git a/include/libfdt.h b/include/libfdt.h index fc7f75b9ff..765d84f5e4 100644 --- a/include/libfdt.h +++ b/include/libfdt.h @@ -136,6 +136,28 @@ uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset); 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); + /**********************************************************************/ /* General functions */ /**********************************************************************/ @@ -582,7 +604,7 @@ const char *fdt_get_alias_namelen(const void *fdt, * value of the property named 'name' in the node /aliases. * * returns: - * a pointer to the expansion of the alias named 'name', of it exists + * 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); @@ -816,6 +838,20 @@ int fdt_node_check_compatible(const void *fdt, int nodeoffset, 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); + /**********************************************************************/ /* Write-in-place functions */ /**********************************************************************/ @@ -1475,4 +1511,68 @@ int fdt_del_node(void *fdt, int nodeoffset); const char *fdt_strerror(int errval); +struct fdt_region { + int offset; + int size; +}; + +/** + * 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); + #endif /* _LIBFDT_H */