[5/5] libfdt: split fdt_region declarations out to <fdt_region.h>

Message ID 1521623017-29312-6-git-send-email-yamada.masahiro@socionext.com
State New
Headers show
Series
  • libfdt: make lib/libfdt/ more synced with scripts/dtc/libfdt/
Related show

Commit Message

Masahiro Yamada March 21, 2018, 9:03 a.m.
fdt_region APIs are not part of libfdt.  They are U-Boot extension
for the verified boot.  Split the declartions related to fdt_region
out ot <fdt_region.h>.  This allows <linux/libfdt.h> to become a
simple wrapper file, like Linux does.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
---

 common/fdt_region.c    |   1 +
 common/image-sig.c     |   1 +
 include/fdt_region.h   | 303 +++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/libfdt.h | 299 ------------------------------------------------
 tools/fdtgrep.c        |   1 +
 tools/image-host.c     |   1 +
 6 files changed, 307 insertions(+), 299 deletions(-)
 create mode 100644 include/fdt_region.h

Comments

Simon Glass March 23, 2018, 2:31 p.m. | #1
Hi Masahiro,

On 21 March 2018 at 03:03, Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
> fdt_region APIs are not part of libfdt.  They are U-Boot extension
> for the verified boot.  Split the declartions related to fdt_region
> out ot <fdt_region.h>.  This allows <linux/libfdt.h> to become a
> simple wrapper file, like Linux does.
>
> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> ---
>
>  common/fdt_region.c    |   1 +
>  common/image-sig.c     |   1 +
>  include/fdt_region.h   | 303 +++++++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/libfdt.h | 299 ------------------------------------------------
>  tools/fdtgrep.c        |   1 +
>  tools/image-host.c     |   1 +
>  6 files changed, 307 insertions(+), 299 deletions(-)
>  create mode 100644 include/fdt_region.h

I think moving the code into a separate header is fine, but I'm not
keen on putting the implementation in common/ as it is a feature of
libfdt. How does this actually help us?

Regards,
Simon
Masahiro Yamada March 23, 2018, 3:57 p.m. | #2
Hi Simon,


2018-03-23 23:31 GMT+09:00 Simon Glass <sjg@chromium.org>:
> Hi Masahiro,
>
> On 21 March 2018 at 03:03, Masahiro Yamada
> <yamada.masahiro@socionext.com> wrote:
>> fdt_region APIs are not part of libfdt.  They are U-Boot extension
>> for the verified boot.  Split the declartions related to fdt_region
>> out ot <fdt_region.h>.  This allows <linux/libfdt.h> to become a
>> simple wrapper file, like Linux does.
>>
>> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
>> ---
>>
>>  common/fdt_region.c    |   1 +
>>  common/image-sig.c     |   1 +
>>  include/fdt_region.h   | 303 +++++++++++++++++++++++++++++++++++++++++++++++++
>>  include/linux/libfdt.h | 299 ------------------------------------------------
>>  tools/fdtgrep.c        |   1 +
>>  tools/image-host.c     |   1 +
>>  6 files changed, 307 insertions(+), 299 deletions(-)
>>  create mode 100644 include/fdt_region.h
>
> I think moving the code into a separate header is fine, but I'm not
> keen on putting the implementation in common/ as it is a feature of
> libfdt. How does this actually help us?

I want to clarify the boundary
between the upstream code and U-Boot own code.


If somebody tries to put new code into lib/libfdt/,
he is doing wrong.
Simon Glass March 23, 2018, 4:55 p.m. | #3
Hi Masahiro,

On 23 March 2018 at 09:57, Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
> Hi Simon,
>
>
> 2018-03-23 23:31 GMT+09:00 Simon Glass <sjg@chromium.org>:
>> Hi Masahiro,
>>
>> On 21 March 2018 at 03:03, Masahiro Yamada
>> <yamada.masahiro@socionext.com> wrote:
>>> fdt_region APIs are not part of libfdt.  They are U-Boot extension
>>> for the verified boot.  Split the declartions related to fdt_region
>>> out ot <fdt_region.h>.  This allows <linux/libfdt.h> to become a
>>> simple wrapper file, like Linux does.
>>>
>>> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
>>> ---
>>>
>>>  common/fdt_region.c    |   1 +
>>>  common/image-sig.c     |   1 +
>>>  include/fdt_region.h   | 303 +++++++++++++++++++++++++++++++++++++++++++++++++
>>>  include/linux/libfdt.h | 299 ------------------------------------------------
>>>  tools/fdtgrep.c        |   1 +
>>>  tools/image-host.c     |   1 +
>>>  6 files changed, 307 insertions(+), 299 deletions(-)
>>>  create mode 100644 include/fdt_region.h
>>
>> I think moving the code into a separate header is fine, but I'm not
>> keen on putting the implementation in common/ as it is a feature of
>> libfdt. How does this actually help us?
>
> I want to clarify the boundary
> between the upstream code and U-Boot own code.
>
>
> If somebody tries to put new code into lib/libfdt/,
> he is doing wrong.

Will still do have some patches locally that are not fully upstream,
at least last time I looked. I'll take another look.

Regards,
Simon

Patch

diff --git a/common/fdt_region.c b/common/fdt_region.c
index 054c4b3..4a02ef4 100644
--- a/common/fdt_region.c
+++ b/common/fdt_region.c
@@ -6,6 +6,7 @@ 
  */
 
 #include <linux/libfdt_env.h>
+#include <fdt_region.h>
 
 #ifndef USE_HOSTCC
 #include <fdt.h>
diff --git a/common/image-sig.c b/common/image-sig.c
index d9f712f..921f378 100644
--- a/common/image-sig.c
+++ b/common/image-sig.c
@@ -12,6 +12,7 @@ 
 #include <malloc.h>
 DECLARE_GLOBAL_DATA_PTR;
 #endif /* !USE_HOSTCC*/
+#include <fdt_region.h>
 #include <image.h>
 #include <u-boot/rsa.h>
 #include <u-boot/rsa-checksum.h>
diff --git a/include/fdt_region.h b/include/fdt_region.h
new file mode 100644
index 0000000..2a5ca7d
--- /dev/null
+++ b/include/fdt_region.h
@@ -0,0 +1,303 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _FDT_REGION_H
+#define _FDT_REGION_H
+
+#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 */
+
+#endif /* _FDT_REGION_H */
diff --git a/include/linux/libfdt.h b/include/linux/libfdt.h
index eeb2344..39dbc88 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_ */
diff --git a/tools/fdtgrep.c b/tools/fdtgrep.c
index 8d33205..bbdefe6 100644
--- a/tools/fdtgrep.c
+++ b/tools/fdtgrep.c
@@ -18,6 +18,7 @@ 
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <fdt_region.h>
 
 #include "fdt_host.h"
 #include "libfdt_internal.h"
diff --git a/tools/image-host.c b/tools/image-host.c
index 8a7469e..fc63c9e 100644
--- a/tools/image-host.c
+++ b/tools/image-host.c
@@ -11,6 +11,7 @@ 
 
 #include "mkimage.h"
 #include <bootm.h>
+#include <fdt_region.h>
 #include <image.h>
 #include <version.h>