Move dtc and libfdt sources from arch/powerpc/boot to scripts/dtc

The powerpc kernel always requires an Open Firmware like device tree
to supply device information.  On systems without OF, this comes from
a flattened device tree blob.  This blob is usually generated by dtc,
a tool which compiles a text description of the device tree into the
flattened format used by the kernel.  Sometimes, the bootwrapper makes
small changes to the pre-compiled device tree blob (e.g. filling in
the size of RAM).  To do this it uses the libfdt library.

Because these are only used on powerpc, the code for both these tools
is included under arch/powerpc/boot (these were imported and are
periodically updated from the upstream dtc tree).

However, the microblaze architecture, currently being prepared for
merging to mainline also uses dtc to produce device tree blobs.  A few
other archs have also mentioned some interest in using dtc.
Therefore, this patch moves dtc and libfdt from arch/powerpc into
scripts, where it can be used by any architecture.

The vast bulk of this patch is a literal move, the rest is adjusting
the various Makefiles to use dtc and libfdt correctly from their new
locations.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

11 files changed, 2893 insertions, 0 deletions

diff --git a/scripts/dtc/libfdt/Makefile.libfdt b/scripts/dtc/libfdt/Makefile.libfdt
new file mode 100644
index 00000000000..6c42acfa21e
--- /dev/null
+++ b/scripts/dtc/libfdt/Makefile.libfdt
@@ -0,0 +1,8 @@
+# Makefile.libfdt
+#
+# This is not a complete Makefile of itself.  Instead, it is designed to
+# be easily embeddable into other systems of Makefiles.
+#
+LIBFDT_INCLUDES = fdt.h libfdt.h
+LIBFDT_SRCS = fdt.c fdt_ro.c fdt_wip.c fdt_sw.c fdt_rw.c fdt_strerror.c
+LIBFDT_OBJS = $(LIBFDT_SRCS:%.c=%.o)
diff --git a/scripts/dtc/libfdt/fdt.c b/scripts/dtc/libfdt/fdt.c
new file mode 100644
index 00000000000..2acaec5923a
--- /dev/null
+++ b/scripts/dtc/libfdt/fdt.c
@@ -0,0 +1,201 @@
+/*
+ * 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 "libfdt_env.h"
+
+#include <fdt.h>
+#include <libfdt.h>
+
+#include "libfdt_internal.h"
+
+int fdt_check_header(const void *fdt)
+{
+	if (fdt_magic(fdt) == FDT_MAGIC) {
+		/* Complete tree */
+		if (fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION)
+			return -FDT_ERR_BADVERSION;
+		if (fdt_last_comp_version(fdt) > FDT_LAST_SUPPORTED_VERSION)
+			return -FDT_ERR_BADVERSION;
+	} else if (fdt_magic(fdt) == FDT_SW_MAGIC) {
+		/* Unfinished sequential-write blob */
+		if (fdt_size_dt_struct(fdt) == 0)
+			return -FDT_ERR_BADSTATE;
+	} else {
+		return -FDT_ERR_BADMAGIC;
+	}
+
+	return 0;
+}
+
+const void *fdt_offset_ptr(const void *fdt, int offset, int len)
+{
+	const char *p;
+
+	if (fdt_version(fdt) >= 0x11)
+		if (((offset + len) < offset)
+		    || ((offset + len) > fdt_size_dt_struct(fdt)))
+			return NULL;
+
+	p = _fdt_offset_ptr(fdt, offset);
+
+	if (p + len < p)
+		return NULL;
+	return p;
+}
+
+uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset)
+{
+	const uint32_t *tagp, *lenp;
+	uint32_t tag;
+	const char *p;
+
+	if (offset % FDT_TAGSIZE)
+		return -1;
+
+	tagp = fdt_offset_ptr(fdt, offset, FDT_TAGSIZE);
+	if (! tagp)
+		return FDT_END; /* premature end */
+	tag = fdt32_to_cpu(*tagp);
+	offset += FDT_TAGSIZE;
+
+	switch (tag) {
+	case FDT_BEGIN_NODE:
+		/* skip name */
+		do {
+			p = fdt_offset_ptr(fdt, offset++, 1);
+		} while (p && (*p != '\0'));
+		if (! p)
+			return FDT_END;
+		break;
+	case FDT_PROP:
+		lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp));
+		if (! lenp)
+			return FDT_END;
+		/* skip name offset, length and value */
+		offset += 2*FDT_TAGSIZE + fdt32_to_cpu(*lenp);
+		break;
+	}
+
+	if (nextoffset)
+		*nextoffset = FDT_TAGALIGN(offset);
+
+	return tag;
+}
+
+int _fdt_check_node_offset(const void *fdt, int offset)
+{
+	if ((offset < 0) || (offset % FDT_TAGSIZE)
+	    || (fdt_next_tag(fdt, offset, &offset) != FDT_BEGIN_NODE))
+		return -FDT_ERR_BADOFFSET;
+
+	return offset;
+}
+
+int fdt_next_node(const void *fdt, int offset, int *depth)
+{
+	int nextoffset = 0;
+	uint32_t tag;
+
+	if (offset >= 0)
+		if ((nextoffset = _fdt_check_node_offset(fdt, offset)) < 0)
+			return nextoffset;
+
+	do {
+		offset = nextoffset;
+		tag = fdt_next_tag(fdt, offset, &nextoffset);
+
+		switch (tag) {
+		case FDT_PROP:
+		case FDT_NOP:
+			break;
+
+		case FDT_BEGIN_NODE:
+			if (depth)
+				(*depth)++;
+			break;
+
+		case FDT_END_NODE:
+			if (depth)
+				(*depth)--;
+			break;
+
+		case FDT_END:
+			return -FDT_ERR_NOTFOUND;
+
+		default:
+			return -FDT_ERR_BADSTRUCTURE;
+		}
+	} while (tag != FDT_BEGIN_NODE);
+
+	return offset;
+}
+
+const char *_fdt_find_string(const char *strtab, int tabsize, const char *s)
+{
+	int len = strlen(s) + 1;
+	const char *last = strtab + tabsize - len;
+	const char *p;
+
+	for (p = strtab; p <= last; p++)
+		if (memcmp(p, s, len) == 0)
+			return p;
+	return NULL;
+}
+
+int fdt_move(const void *fdt, void *buf, int bufsize)
+{
+	FDT_CHECK_HEADER(fdt);
+
+	if (fdt_totalsize(fdt) > bufsize)
+		return -FDT_ERR_NOSPACE;
+
+	memmove(buf, fdt, fdt_totalsize(fdt));
+	return 0;
+}
diff --git a/scripts/dtc/libfdt/fdt.h b/scripts/dtc/libfdt/fdt.h
new file mode 100644
index 00000000000..48ccfd91000
--- /dev/null
+++ b/scripts/dtc/libfdt/fdt.h
@@ -0,0 +1,60 @@
+#ifndef _FDT_H
+#define _FDT_H
+
+#ifndef __ASSEMBLY__
+
+struct fdt_header {
+	uint32_t magic;			 /* magic word FDT_MAGIC */
+	uint32_t totalsize;		 /* total size of DT block */
+	uint32_t off_dt_struct;		 /* offset to structure */
+	uint32_t off_dt_strings;	 /* offset to strings */
+	uint32_t off_mem_rsvmap;	 /* offset to memory reserve map */
+	uint32_t version;		 /* format version */
+	uint32_t last_comp_version;	 /* last compatible version */
+
+	/* version 2 fields below */
+	uint32_t boot_cpuid_phys;	 /* Which physical CPU id we're
+					    booting on */
+	/* version 3 fields below */
+	uint32_t size_dt_strings;	 /* size of the strings block */
+
+	/* version 17 fields below */
+	uint32_t size_dt_struct;	 /* size of the structure block */
+};
+
+struct fdt_reserve_entry {
+	uint64_t address;
+	uint64_t size;
+};
+
+struct fdt_node_header {
+	uint32_t tag;
+	char name[0];
+};
+
+struct fdt_property {
+	uint32_t tag;
+	uint32_t len;
+	uint32_t nameoff;
+	char data[0];
+};
+
+#endif /* !__ASSEMBLY */
+
+#define FDT_MAGIC	0xd00dfeed	/* 4: version, 4: total size */
+#define FDT_TAGSIZE	sizeof(uint32_t)
+
+#define FDT_BEGIN_NODE	0x1		/* Start node: full name */
+#define FDT_END_NODE	0x2		/* End node */
+#define FDT_PROP	0x3		/* Property: name off,
+					   size, content */
+#define FDT_NOP		0x4		/* nop */
+#define FDT_END		0x9
+
+#define FDT_V1_SIZE	(7*sizeof(uint32_t))
+#define FDT_V2_SIZE	(FDT_V1_SIZE + sizeof(uint32_t))
+#define FDT_V3_SIZE	(FDT_V2_SIZE + sizeof(uint32_t))
+#define FDT_V16_SIZE	FDT_V3_SIZE
+#define FDT_V17_SIZE	(FDT_V16_SIZE + sizeof(uint32_t))
+
+#endif /* _FDT_H */
diff --git a/scripts/dtc/libfdt/fdt_ro.c b/scripts/dtc/libfdt/fdt_ro.c
new file mode 100644
index 00000000000..fbbba44fcd0
--- /dev/null
+++ b/scripts/dtc/libfdt/fdt_ro.c
@@ -0,0 +1,469 @@
+/*
+ * 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 "libfdt_env.h"
+
+#include <fdt.h>
+#include <libfdt.h>
+
+#include "libfdt_internal.h"
+
+static int _fdt_nodename_eq(const void *fdt, int offset,
+			    const char *s, int len)
+{
+	const char *p = fdt_offset_ptr(fdt, offset + FDT_TAGSIZE, len+1);
+
+	if (! p)
+		/* short match */
+		return 0;
+
+	if (memcmp(p, s, len) != 0)
+		return 0;
+
+	if (p[len] == '\0')
+		return 1;
+	else if (!memchr(s, '@', len) && (p[len] == '@'))
+		return 1;
+	else
+		return 0;
+}
+
+const char *fdt_string(const void *fdt, int stroffset)
+{
+	return (const char *)fdt + fdt_off_dt_strings(fdt) + stroffset;
+}
+
+int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size)
+{
+	FDT_CHECK_HEADER(fdt);
+	*address = fdt64_to_cpu(_fdt_mem_rsv(fdt, n)->address);
+	*size = fdt64_to_cpu(_fdt_mem_rsv(fdt, n)->size);
+	return 0;
+}
+
+int fdt_num_mem_rsv(const void *fdt)
+{
+	int i = 0;
+
+	while (fdt64_to_cpu(_fdt_mem_rsv(fdt, i)->size) != 0)
+		i++;
+	return i;
+}
+
+int fdt_subnode_offset_namelen(const void *fdt, int offset,
+			       const char *name, int namelen)
+{
+	int depth;
+
+	FDT_CHECK_HEADER(fdt);
+
+	for (depth = 0, offset = fdt_next_node(fdt, offset, &depth);
+	     (offset >= 0) && (depth > 0);
+	     offset = fdt_next_node(fdt, offset, &depth)) {
+		if (depth < 0)
+			return -FDT_ERR_NOTFOUND;
+		else if ((depth == 1)
+			 && _fdt_nodename_eq(fdt, offset, name, namelen))
+			return offset;
+	}
+
+	if (offset < 0)
+		return offset; /* error */
+	else
+		return -FDT_ERR_NOTFOUND;
+}
+
+int fdt_subnode_offset(const void *fdt, int parentoffset,
+		       const char *name)
+{
+	return fdt_subnode_offset_namelen(fdt, parentoffset, name, strlen(name));
+}
+
+int fdt_path_offset(const void *fdt, const char *path)
+{
+	const char *end = path + strlen(path);
+	const char *p = path;
+	int offset = 0;
+
+	FDT_CHECK_HEADER(fdt);
+
+	if (*path != '/')
+		return -FDT_ERR_BADPATH;
+
+	while (*p) {
+		const char *q;
+
+		while (*p == '/')
+			p++;
+		if (! *p)
+			return offset;
+		q = strchr(p, '/');
+		if (! q)
+			q = end;
+
+		offset = fdt_subnode_offset_namelen(fdt, offset, p, q-p);
+		if (offset < 0)
+			return offset;
+
+		p = q;
+	}
+
+	return offset;
+}
+
+const char *fdt_get_name(const void *fdt, int nodeoffset, int *len)
+{
+	const struct fdt_node_header *nh = _fdt_offset_ptr(fdt, nodeoffset);
+	int err;
+
+	if (((err = fdt_check_header(fdt)) != 0)
+	    || ((err = _fdt_check_node_offset(fdt, nodeoffset)) < 0))
+			goto fail;
+
+	if (len)
+		*len = strlen(nh->name);
+
+	return nh->name;
+
+ fail:
+	if (len)
+		*len = err;
+	return NULL;
+}
+
+const struct fdt_property *fdt_get_property(const void *fdt,
+					    int nodeoffset,
+					    const char *name, int *lenp)
+{
+	uint32_t tag;
+	const struct fdt_property *prop;
+	int namestroff;
+	int offset, nextoffset;
+	int err;
+
+	if (((err = fdt_check_header(fdt)) != 0)
+	    || ((err = _fdt_check_node_offset(fdt, nodeoffset)) < 0))
+			goto fail;
+
+	nextoffset = err;
+	do {
+		offset = nextoffset;
+
+		tag = fdt_next_tag(fdt, offset, &nextoffset);
+		switch (tag) {
+		case FDT_END:
+			err = -FDT_ERR_TRUNCATED;
+			goto fail;
+
+		case FDT_BEGIN_NODE:
+		case FDT_END_NODE:
+		case FDT_NOP:
+			break;
+
+		case FDT_PROP:
+			err = -FDT_ERR_BADSTRUCTURE;
+			prop = fdt_offset_ptr(fdt, offset, sizeof(*prop));
+			if (! prop)
+				goto fail;
+			namestroff = fdt32_to_cpu(prop->nameoff);
+			if (strcmp(fdt_string(fdt, namestroff), name) == 0) {
+				/* Found it! */
+				int len = fdt32_to_cpu(prop->len);
+				prop = fdt_offset_ptr(fdt, offset,
+						      sizeof(*prop)+len);
+				if (! prop)
+					goto fail;
+
+				if (lenp)
+					*lenp = len;
+
+				return prop;
+			}
+			break;
+
+		default:
+			err = -FDT_ERR_BADSTRUCTURE;
+			goto fail;
+		}
+	} while ((tag != FDT_BEGIN_NODE) && (tag != FDT_END_NODE));
+
+	err = -FDT_ERR_NOTFOUND;
+ fail:
+	if (lenp)
+		*lenp = err;
+	return NULL;
+}
+
+const void *fdt_getprop(const void *fdt, int nodeoffset,
+		  const char *name, int *lenp)
+{
+	const struct fdt_property *prop;
+
+	prop = fdt_get_property(fdt, nodeoffset, name, lenp);
+	if (! prop)
+		return NULL;
+
+	return prop->data;
+}
+
+uint32_t fdt_get_phandle(const void *fdt, int nodeoffset)
+{
+	const uint32_t *php;
+	int len;
+
+	php = fdt_getprop(fdt, nodeoffset, "linux,phandle", &len);
+	if (!php || (len != sizeof(*php)))
+		return 0;
+
+	return fdt32_to_cpu(*php);
+}
+
+int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen)
+{
+	int pdepth = 0, p = 0;
+	int offset, depth, namelen;
+	const char *name;
+
+	FDT_CHECK_HEADER(fdt);
+
+	if (buflen < 2)
+		return -FDT_ERR_NOSPACE;
+
+	for (offset = 0, depth = 0;
+	     (offset >= 0) && (offset <= nodeoffset);
+	     offset = fdt_next_node(fdt, offset, &depth)) {
+		if (pdepth < depth)
+			continue; /* overflowed buffer */
+
+		while (pdepth > depth) {
+			do {
+				p--;
+			} while (buf[p-1] != '/');
+			pdepth--;
+		}
+
+		name = fdt_get_name(fdt, offset, &namelen);
+		if (!name)
+			return namelen;
+		if ((p + namelen + 1) <= buflen) {
+			memcpy(buf + p, name, namelen);
+			p += namelen;
+			buf[p++] = '/';
+			pdepth++;
+		}
+
+		if (offset == nodeoffset) {
+			if (pdepth < (depth + 1))
+				return -FDT_ERR_NOSPACE;
+
+			if (p > 1) /* special case so that root path is "/", not "" */
+				p--;
+			buf[p] = '\0';
+			return p;
+		}
+	}
+
+	if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
+		return -FDT_ERR_BADOFFSET;
+	else if (offset == -FDT_ERR_BADOFFSET)
+		return -FDT_ERR_BADSTRUCTURE;
+
+	return offset; /* error from fdt_next_node() */
+}
+
+int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
+				 int supernodedepth, int *nodedepth)
+{
+	int offset, depth;
+	int supernodeoffset = -FDT_ERR_INTERNAL;
+
+	FDT_CHECK_HEADER(fdt);
+
+	if (supernodedepth < 0)
+		return -FDT_ERR_NOTFOUND;
+
+	for (offset = 0, depth = 0;
+	     (offset >= 0) && (offset <= nodeoffset);
+	     offset = fdt_next_node(fdt, offset, &depth)) {
+		if (depth == supernodedepth)
+			supernodeoffset = offset;
+
+		if (offset == nodeoffset) {
+			if (nodedepth)
+				*nodedepth = depth;
+
+			if (supernodedepth > depth)
+				return -FDT_ERR_NOTFOUND;
+			else
+				return supernodeoffset;
+		}
+	}
+
+	if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
+		return -FDT_ERR_BADOFFSET;
+	else if (offset == -FDT_ERR_BADOFFSET)
+		return -FDT_ERR_BADSTRUCTURE;
+
+	return offset; /* error from fdt_next_node() */
+}
+
+int fdt_node_depth(const void *fdt, int nodeoffset)
+{
+	int nodedepth;
+	int err;
+
+	err = fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, &nodedepth);
+	if (err)
+		return (err < 0) ? err : -FDT_ERR_INTERNAL;
+	return nodedepth;
+}
+
+int fdt_parent_offset(const void *fdt, int nodeoffset)
+{
+	int nodedepth = fdt_node_depth(fdt, nodeoffset);
+
+	if (nodedepth < 0)
+		return nodedepth;
+	return fdt_supernode_atdepth_offset(fdt, nodeoffset,
+					    nodedepth - 1, NULL);
+}
+
+int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
+				  const char *propname,
+				  const void *propval, int proplen)
+{
+	int offset;
+	const void *val;
+	int len;
+
+	FDT_CHECK_HEADER(fdt);
+
+	/* FIXME: The algorithm here is pretty horrible: we scan each
+	 * property of a node in fdt_getprop(), then if that didn't
+	 * find what we want, we scan over them again making our way
+	 * to the next node.  Still it's the easiest to implement
+	 * approach; performance can come later. */
+	for (offset = fdt_next_node(fdt, startoffset, NULL);
+	     offset >= 0;
+	     offset = fdt_next_node(fdt, offset, NULL)) {
+		val = fdt_getprop(fdt, offset, propname, &len);
+		if (val && (len == proplen)
+		    && (memcmp(val, propval, len) == 0))
+			return offset;
+	}
+
+	return offset; /* error from fdt_next_node() */
+}
+
+int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle)
+{
+	if ((phandle == 0) || (phandle == -1))
+		return -FDT_ERR_BADPHANDLE;
+	phandle = cpu_to_fdt32(phandle);
+	return fdt_node_offset_by_prop_value(fdt, -1, "linux,phandle",
+					     &phandle, sizeof(phandle));
+}
+
+int _stringlist_contains(const char *strlist, int listlen, const char *str)
+{
+	int len = strlen(str);
+	const char *p;
+
+	while (listlen >= len) {
+		if (memcmp(str, strlist, len+1) == 0)
+			return 1;
+		p = memchr(strlist, '\0', listlen);
+		if (!p)
+			return 0; /* malformed strlist.. */
+		listlen -= (p-strlist) + 1;
+		strlist = p + 1;
+	}
+	return 0;
+}
+
+int fdt_node_check_compatible(const void *fdt, int nodeoffset,
+			      const char *compatible)
+{
+	const void *prop;
+	int len;
+
+	prop = fdt_getprop(fdt, nodeoffset, "compatible", &len);
+	if (!prop)
+		return len;
+	if (_stringlist_contains(prop, len, compatible))
+		return 0;
+	else
+		return 1;
+}
+
+int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
+				  const char *compatible)
+{
+	int offset, err;
+
+	FDT_CHECK_HEADER(fdt);
+
+	/* FIXME: The algorithm here is pretty horrible: we scan each
+	 * property of a node in fdt_node_check_compatible(), then if
+	 * that didn't find what we want, we scan over them again
+	 * making our way to the next node.  Still it's the easiest to
+	 * implement approach; performance can come later. */
+	for (offset = fdt_next_node(fdt, startoffset, NULL);
+	     offset >= 0;
+	     offset = fdt_next_node(fdt, offset, NULL)) {
+		err = fdt_node_check_compatible(fdt, offset, compatible);
+		if ((err < 0) && (err != -FDT_ERR_NOTFOUND))
+			return err;
+		else if (err == 0)
+			return offset;
+	}
+
+	return offset; /* error from fdt_next_node() */
+}
diff --git a/scripts/dtc/libfdt/fdt_rw.c b/scripts/dtc/libfdt/fdt_rw.c
new file mode 100644
index 00000000000..8e7ec4cb7bc
--- /dev/null
+++ b/scripts/dtc/libfdt/fdt_rw.c
@@ -0,0 +1,463 @@
+/*
+ * 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 "libfdt_env.h"
+
+#include <fdt.h>
+#include <libfdt.h>
+
+#include "libfdt_internal.h"
+
+static int _fdt_blocks_misordered(const void *fdt,
+			      int mem_rsv_size, int struct_size)
+{
+	return (fdt_off_mem_rsvmap(fdt) < FDT_ALIGN(sizeof(struct fdt_header), 8))
+		|| (fdt_off_dt_struct(fdt) <
+		    (fdt_off_mem_rsvmap(fdt) + mem_rsv_size))
+		|| (fdt_off_dt_strings(fdt) <
+		    (fdt_off_dt_struct(fdt) + struct_size))
+		|| (fdt_totalsize(fdt) <
+		    (fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt)));
+}
+
+static int _fdt_rw_check_header(void *fdt)
+{
+	FDT_CHECK_HEADER(fdt);
+
+	if (fdt_version(fdt) < 17)
+		return -FDT_ERR_BADVERSION;
+	if (_fdt_blocks_misordered(fdt, sizeof(struct fdt_reserve_entry),
+				   fdt_size_dt_struct(fdt)))
+		return -FDT_ERR_BADLAYOUT;
+	if (fdt_version(fdt) > 17)
+		fdt_set_version(fdt, 17);
+
+	return 0;
+}
+
+#define FDT_RW_CHECK_HEADER(fdt) \
+	{ \
+		int err; \
+		if ((err = _fdt_rw_check_header(fdt)) != 0) \
+			return err; \
+	}
+
+static inline int _fdt_data_size(void *fdt)
+{
+	return fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);
+}
+
+static int _fdt_splice(void *fdt, void *splicepoint, int oldlen, int newlen)
+{
+	char *p = splicepoint;
+	char *end = (char *)fdt + _fdt_data_size(fdt);
+
+	if (((p + oldlen) < p) || ((p + oldlen) > end))
+		return -FDT_ERR_BADOFFSET;
+	if ((end - oldlen + newlen) > ((char *)fdt + fdt_totalsize(fdt)))
+		return -FDT_ERR_NOSPACE;
+	memmove(p + newlen, p + oldlen, end - p - oldlen);
+	return 0;
+}
+
+static int _fdt_splice_mem_rsv(void *fdt, struct fdt_reserve_entry *p,
+			       int oldn, int newn)
+{
+	int delta = (newn - oldn) * sizeof(*p);
+	int err;
+	err = _fdt_splice(fdt, p, oldn * sizeof(*p), newn * sizeof(*p));
+	if (err)
+		return err;
+	fdt_set_off_dt_struct(fdt, fdt_off_dt_struct(fdt) + delta);
+	fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);
+	return 0;
+}
+
+static int _fdt_splice_struct(void *fdt, void *p,
+			      int oldlen, int newlen)
+{
+	int delta = newlen - oldlen;
+	int err;
+
+	if ((err = _fdt_splice(fdt, p, oldlen, newlen)))
+		return err;
+
+	fdt_set_size_dt_struct(fdt, fdt_size_dt_struct(fdt) + delta);
+	fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);
+	return 0;
+}
+
+static int _fdt_splice_string(void *fdt, int newlen)
+{
+	void *p = (char *)fdt
+		+ fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);
+	int err;
+
+	if ((err = _fdt_splice(fdt, p, 0, newlen)))
+		return err;
+
+	fdt_set_size_dt_strings(fdt, fdt_size_dt_strings(fdt) + newlen);
+	return 0;
+}
+
+static int _fdt_find_add_string(void *fdt, const char *s)
+{
+	char *strtab = (char *)fdt + fdt_off_dt_strings(fdt);
+	const char *p;
+	char *new;
+	int len = strlen(s) + 1;
+	int err;
+
+	p = _fdt_find_string(strtab, fdt_size_dt_strings(fdt), s);
+	if (p)
+		/* found it */
+		return (p - strtab);
+
+	new = strtab + fdt_size_dt_strings(fdt);
+	err = _fdt_splice_string(fdt, len);
+	if (err)
+		return err;
+
+	memcpy(new, s, len);
+	return (new - strtab);
+}
+
+int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size)
+{
+	struct fdt_reserve_entry *re;
+	int err;
+
+	FDT_RW_CHECK_HEADER(fdt);
+
+	re = _fdt_mem_rsv_w(fdt, fdt_num_mem_rsv(fdt));
+	err = _fdt_splice_mem_rsv(fdt, re, 0, 1);
+	if (err)
+		return err;
+
+	re->address = cpu_to_fdt64(address);
+	re->size = cpu_to_fdt64(size);
+	return 0;
+}
+
+int fdt_del_mem_rsv(void *fdt, int n)
+{
+	struct fdt_reserve_entry *re = _fdt_mem_rsv_w(fdt, n);
+	int err;
+
+	FDT_RW_CHECK_HEADER(fdt);
+
+	if (n >= fdt_num_mem_rsv(fdt))
+		return -FDT_ERR_NOTFOUND;
+
+	err = _fdt_splice_mem_rsv(fdt, re, 1, 0);
+	if (err)
+		return err;
+	return 0;
+}
+
+static int _fdt_resize_property(void *fdt, int nodeoffset, const char *name,
+				int len, struct fdt_property **prop)
+{
+	int oldlen;
+	int err;
+
+	*prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen);
+	if (! (*prop))
+		return oldlen;
+
+	if ((err = _fdt_splice_struct(fdt, (*prop)->data, FDT_TAGALIGN(oldlen),
+				      FDT_TAGALIGN(len))))
+		return err;
+
+	(*prop)->len = cpu_to_fdt32(len);
+	return 0;
+}
+
+static int _fdt_add_property(void *fdt, int nodeoffset, const char *name,
+			     int len, struct fdt_property **prop)
+{
+	int proplen;
+	int nextoffset;
+	int namestroff;
+	int err;
+
+	if ((nextoffset = _fdt_check_node_offset(fdt, nodeoffset)) < 0)
+		return nextoffset;
+
+	namestroff = _fdt_find_add_string(fdt, name);
+	if (namestroff < 0)
+		return namestroff;
+
+	*prop = _fdt_offset_ptr_w(fdt, nextoffset);
+	proplen = sizeof(**prop) + FDT_TAGALIGN(len);
+
+	err = _fdt_splice_struct(fdt, *prop, 0, proplen);
+	if (err)
+		return err;
+
+	(*prop)->tag = cpu_to_fdt32(FDT_PROP);
+	(*prop)->nameoff = cpu_to_fdt32(namestroff);
+	(*prop)->len = cpu_to_fdt32(len);
+	return 0;
+}
+
+int fdt_set_name(void *fdt, int nodeoffset, const char *name)
+{
+	char *namep;
+	int oldlen, newlen;
+	int err;
+
+	FDT_RW_CHECK_HEADER(fdt);
+
+	namep = (char *)(uintptr_t)fdt_get_name(fdt, nodeoffset, &oldlen);
+	if (!namep)
+		return oldlen;
+
+	newlen = strlen(name);
+
+	err = _fdt_splice_struct(fdt, namep, FDT_TAGALIGN(oldlen+1),
+				 FDT_TAGALIGN(newlen+1));
+	if (err)
+		return err;
+
+	memcpy(namep, name, newlen+1);
+	return 0;
+}
+
+int fdt_setprop(void *fdt, int nodeoffset, const char *name,
+		const void *val, int len)
+{
+	struct fdt_property *prop;
+	int err;
+
+	FDT_RW_CHECK_HEADER(fdt);
+
+	err = _fdt_resize_property(fdt, nodeoffset, name, len, &prop);
+	if (err == -FDT_ERR_NOTFOUND)
+		err = _fdt_add_property(fdt, nodeoffset, name, len, &prop);
+	if (err)
+		return err;
+
+	memcpy(prop->data, val, len);
+	return 0;
+}
+
+int fdt_delprop(void *fdt, int nodeoffset, const char *name)
+{
+	struct fdt_property *prop;
+	int len, proplen;
+
+	FDT_RW_CHECK_HEADER(fdt);
+
+	prop = fdt_get_property_w(fdt, nodeoffset, name, &len);
+	if (! prop)
+		return len;
+
+	proplen = sizeof(*prop) + FDT_TAGALIGN(len);
+	return _fdt_splice_struct(fdt, prop, proplen, 0);
+}
+
+int fdt_add_subnode_namelen(void *fdt, int parentoffset,
+			    const char *name, int namelen)
+{