include/linux/libfdt.h - github/trini/u-boot - Gitiles

 /* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _INCLUDE_LIBFDT_H_
 #define _INCLUDE_LIBFDT_H_

 #ifndef USE_HOSTCC
 #include <linux/libfdt_env.h>
 #endif
 #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 */

 /* adding a ramdisk needs 0x44 bytes in version 2008.10 */
 #define FDT_RAMDISK_OVERHEAD	0x80

 #endif /* _INCLUDE_LIBFDT_H_ */
	/* SPDX-License-Identifier: GPL-2.0 */
	#ifndef _INCLUDE_LIBFDT_H_
	#define _INCLUDE_LIBFDT_H_

	#ifndef USE_HOSTCC
	#include <linux/libfdt_env.h>
	#endif
	#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 */

	/* adding a ramdisk needs 0x44 bytes in version 2008.10 */
	#define FDT_RAMDISK_OVERHEAD 0x80

	#endif /* _INCLUDE_LIBFDT_H_ */