X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=include%2Flinux%2Flibfdt.h;h=39dbc88aa549b3a3849233dfcaaf9c26565a6a1d;hb=64045a6a173e6cf74a9c30bbe21a93d105be289e;hp=eeb2344971f3ff9489ae454647bb4f951bf170df;hpb=3e69db1223b9db82705fcc96b76caf0d8a468d12;p=oweals%2Fu-boot.git diff --git a/include/linux/libfdt.h b/include/linux/libfdt.h index eeb2344971..39dbc88aa5 100644 --- a/include/linux/libfdt.h +++ b/include/linux/libfdt.h @@ -8,305 +8,6 @@ #include "../../scripts/dtc/libfdt/libfdt.h" /* U-Boot local hacks */ - -#ifndef SWIG /* Not available in Python */ -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 many 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 /* SWIG */ - extern struct fdt_header *working_fdt; /* Pointer to the working fdt */ #endif /* _INCLUDE_LIBFDT_H_ */