libfdt: Move to version v1.4.6-9

This import adds FDT overlay plus brings in the latest bugfixes upstream.

As noted in the below url, there is a performance problem with 1.4.7 so we
target version 1.4.6-9 instead.

https://github.com/ARM-software/arm-trusted-firmware/pull/1657

Upstream commit aadd0b65c987 ("checks: centralize printing of property
names in failure messages")

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Suggested-by: Jens Wiklander <jens.wiklander@linaro.org>
Suggested-by: Etienne Carriere <etienne.carriere@linaro.org>
Reviewed-by: Etienne Carriere <etienne.carriere@linaro.org>

13 files changed, 1735 insertions, 214 deletions

diff --git a/core/lib/libfdt/fdt.c b/core/lib/libfdt/fdt.c
index 64ec76d2..7c5cab7b 100644
--- a/core/lib/libfdt/fdt.c
+++ b/core/lib/libfdt/fdt.c
@@ -89,7 +89,7 @@ const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int len)
 		    || ((offset + len) > fdt_size_dt_struct(fdt)))
 			return NULL;
 
-	return _fdt_offset_ptr(fdt, offset);
+	return fdt_offset_ptr_(fdt, offset);
 }
 
 uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
@@ -124,6 +124,9 @@ uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
 		/* skip-name offset, length and value */
 		offset += sizeof(struct fdt_property) - FDT_TAGSIZE
 			+ fdt32_to_cpu(*lenp);
+		if (fdt_version(fdt) < 0x10 && fdt32_to_cpu(*lenp) >= 8 &&
+		    ((offset - fdt32_to_cpu(*lenp)) % 8) != 0)
+			offset += 4;
 		break;
 
 	case FDT_END:
@@ -142,7 +145,7 @@ uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
 	return tag;
 }
 
-int _fdt_check_node_offset(const void *fdt, int offset)
+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))
@@ -151,7 +154,7 @@ int _fdt_check_node_offset(const void *fdt, int offset)
 	return offset;
 }
 
-int _fdt_check_prop_offset(const void *fdt, int offset)
+int fdt_check_prop_offset_(const void *fdt, int offset)
 {
 	if ((offset < 0) || (offset % FDT_TAGSIZE)
 	    || (fdt_next_tag(fdt, offset, &offset) != FDT_PROP))
@@ -166,7 +169,7 @@ int fdt_next_node(const void *fdt, int offset, int *depth)
 	uint32_t tag;
 
 	if (offset >= 0)
-		if ((nextoffset = _fdt_check_node_offset(fdt, offset)) < 0)
+		if ((nextoffset = fdt_check_node_offset_(fdt, offset)) < 0)
 			return nextoffset;
 
 	do {
@@ -228,7 +231,7 @@ int fdt_next_subnode(const void *fdt, int offset)
 	return offset;
 }
 
-const char *_fdt_find_string(const char *strtab, int tabsize, const char *s)
+const char *fdt_find_string_(const char *strtab, int tabsize, const char *s)
 {
 	int len = strlen(s) + 1;
 	const char *last = strtab + tabsize - len;
diff --git a/core/lib/libfdt/fdt_empty_tree.c b/core/lib/libfdt/fdt_empty_tree.c
index a979b516..8c368633 100644
--- a/core/lib/libfdt/fdt_empty_tree.c
+++ b/core/lib/libfdt/fdt_empty_tree.c
@@ -82,4 +82,3 @@ int fdt_create_empty_tree(void *buf, int bufsize)
 
 	return fdt_open_into(buf, buf, bufsize);
 }
-
diff --git a/core/lib/libfdt/fdt_overlay.c b/core/lib/libfdt/fdt_overlay.c
new file mode 100644
index 00000000..6de1960a
--- /dev/null
+++ b/core/lib/libfdt/fdt_overlay.c
@@ -0,0 +1,913 @@
+// SPDX-License-Identifier: (BSD-2-Clause OR GPL-2.0+)
+/*
+ * libfdt - Flat Device Tree manipulation
+ * Copyright (C) 2016 Free Electrons
+ * Copyright (C) 2016 NextThing Co.
+ *
+ * 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"
+
+/**
+ * overlay_get_target_phandle - retrieves the target phandle of a fragment
+ * @fdto: pointer to the device tree overlay blob
+ * @fragment: node offset of the fragment in the overlay
+ *
+ * overlay_get_target_phandle() retrieves the target phandle of an
+ * overlay fragment when that fragment uses a phandle (target
+ * property) instead of a path (target-path property).
+ *
+ * returns:
+ *      the phandle pointed by the target property
+ *      0, if the phandle was not found
+ *	-1, if the phandle was malformed
+ */
+static uint32_t overlay_get_target_phandle(const void *fdto, int fragment)
+{
+	const fdt32_t *val;
+	int len;
+
+	val = fdt_getprop(fdto, fragment, "target", &len);
+	if (!val)
+		return 0;
+
+	if ((len != sizeof(*val)) || (fdt32_to_cpu(*val) == (uint32_t)-1))
+		return (uint32_t)-1;
+
+	return fdt32_to_cpu(*val);
+}
+
+/**
+ * overlay_get_target - retrieves the offset of a fragment's target
+ * @fdt: Base device tree blob
+ * @fdto: Device tree overlay blob
+ * @fragment: node offset of the fragment in the overlay
+ * @pathp: pointer which receives the path of the target (or NULL)
+ *
+ * overlay_get_target() retrieves the target offset in the base
+ * device tree of a fragment, no matter how the actual targetting is
+ * done (through a phandle or a path)
+ *
+ * returns:
+ *      the targetted node offset in the base device tree
+ *      Negative error code on error
+ */
+static int overlay_get_target(const void *fdt, const void *fdto,
+			      int fragment, char const **pathp)
+{
+	uint32_t phandle;
+	const char *path = NULL;
+	int path_len = 0, ret;
+
+	/* Try first to do a phandle based lookup */
+	phandle = overlay_get_target_phandle(fdto, fragment);
+	if (phandle == (uint32_t)-1)
+		return -FDT_ERR_BADPHANDLE;
+
+	/* no phandle, try path */
+	if (!phandle) {
+		/* And then a path based lookup */
+		path = fdt_getprop(fdto, fragment, "target-path", &path_len);
+		if (path)
+			ret = fdt_path_offset(fdt, path);
+		else
+			ret = path_len;
+	} else
+		ret = fdt_node_offset_by_phandle(fdt, phandle);
+
+	/*
+	* If we haven't found either a target or a
+	* target-path property in a node that contains a
+	* __overlay__ subnode (we wouldn't be called
+	* otherwise), consider it a improperly written
+	* overlay
+	*/
+	if (ret < 0 && path_len == -FDT_ERR_NOTFOUND)
+		ret = -FDT_ERR_BADOVERLAY;
+
+	/* return on error */
+	if (ret < 0)
+		return ret;
+
+	/* return pointer to path (if available) */
+	if (pathp)
+		*pathp = path ? path : NULL;
+
+	return ret;
+}
+
+/**
+ * overlay_phandle_add_offset - Increases a phandle by an offset
+ * @fdt: Base device tree blob
+ * @node: Device tree overlay blob
+ * @name: Name of the property to modify (phandle or linux,phandle)
+ * @delta: offset to apply
+ *
+ * overlay_phandle_add_offset() increments a node phandle by a given
+ * offset.
+ *
+ * returns:
+ *      0 on success.
+ *      Negative error code on error
+ */
+static int overlay_phandle_add_offset(void *fdt, int node,
+				      const char *name, uint32_t delta)
+{
+	const fdt32_t *val;
+	uint32_t adj_val;
+	int len;
+
+	val = fdt_getprop(fdt, node, name, &len);
+	if (!val)
+		return len;
+
+	if (len != sizeof(*val))
+		return -FDT_ERR_BADPHANDLE;
+
+	adj_val = fdt32_to_cpu(*val);
+	if ((adj_val + delta) < adj_val)
+		return -FDT_ERR_NOPHANDLES;
+
+	adj_val += delta;
+	if (adj_val == (uint32_t)-1)
+		return -FDT_ERR_NOPHANDLES;
+
+	return fdt_setprop_inplace_u32(fdt, node, name, adj_val);
+}
+
+/**
+ * overlay_adjust_node_phandles - Offsets the phandles of a node
+ * @fdto: Device tree overlay blob
+ * @node: Offset of the node we want to adjust
+ * @delta: Offset to shift the phandles of
+ *
+ * overlay_adjust_node_phandles() adds a constant to all the phandles
+ * of a given node. This is mainly use as part of the overlay
+ * application process, when we want to update all the overlay
+ * phandles to not conflict with the overlays of the base device tree.
+ *
+ * returns:
+ *      0 on success
+ *      Negative error code on failure
+ */
+static int overlay_adjust_node_phandles(void *fdto, int node,
+					uint32_t delta)
+{
+	int child;
+	int ret;
+
+	ret = overlay_phandle_add_offset(fdto, node, "phandle", delta);
+	if (ret && ret != -FDT_ERR_NOTFOUND)
+		return ret;
+
+	ret = overlay_phandle_add_offset(fdto, node, "linux,phandle", delta);
+	if (ret && ret != -FDT_ERR_NOTFOUND)
+		return ret;
+
+	fdt_for_each_subnode(child, fdto, node) {
+		ret = overlay_adjust_node_phandles(fdto, child, delta);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * overlay_adjust_local_phandles - Adjust the phandles of a whole overlay
+ * @fdto: Device tree overlay blob
+ * @delta: Offset to shift the phandles of
+ *
+ * overlay_adjust_local_phandles() adds a constant to all the
+ * phandles of an overlay. This is mainly use as part of the overlay
+ * application process, when we want to update all the overlay
+ * phandles to not conflict with the overlays of the base device tree.
+ *
+ * returns:
+ *      0 on success
+ *      Negative error code on failure
+ */
+static int overlay_adjust_local_phandles(void *fdto, uint32_t delta)
+{
+	/*
+	 * Start adjusting the phandles from the overlay root
+	 */
+	return overlay_adjust_node_phandles(fdto, 0, delta);
+}
+
+/**
+ * overlay_update_local_node_references - Adjust the overlay references
+ * @fdto: Device tree overlay blob
+ * @tree_node: Node offset of the node to operate on
+ * @fixup_node: Node offset of the matching local fixups node
+ * @delta: Offset to shift the phandles of
+ *
+ * overlay_update_local_nodes_references() update the phandles
+ * pointing to a node within the device tree overlay by adding a
+ * constant delta.
+ *
+ * This is mainly used as part of a device tree application process,
+ * where you want the device tree overlays phandles to not conflict
+ * with the ones from the base device tree before merging them.
+ *
+ * returns:
+ *      0 on success
+ *      Negative error code on failure
+ */
+static int overlay_update_local_node_references(void *fdto,
+						int tree_node,
+						int fixup_node,
+						uint32_t delta)
+{
+	int fixup_prop;
+	int fixup_child;
+	int ret;
+
+	fdt_for_each_property_offset(fixup_prop, fdto, fixup_node) {
+		const fdt32_t *fixup_val;
+		const char *tree_val;
+		const char *name;
+		int fixup_len;
+		int tree_len;
+		int i;
+
+		fixup_val = fdt_getprop_by_offset(fdto, fixup_prop,
+						  &name, &fixup_len);
+		if (!fixup_val)
+			return fixup_len;
+
+		if (fixup_len % sizeof(uint32_t))
+			return -FDT_ERR_BADOVERLAY;
+
+		tree_val = fdt_getprop(fdto, tree_node, name, &tree_len);
+		if (!tree_val) {
+			if (tree_len == -FDT_ERR_NOTFOUND)
+				return -FDT_ERR_BADOVERLAY;
+
+			return tree_len;
+		}
+
+		for (i = 0; i < (fixup_len / sizeof(uint32_t)); i++) {
+			fdt32_t adj_val;
+			uint32_t poffset;
+
+			poffset = fdt32_to_cpu(fixup_val[i]);
+
+			/*
+			 * phandles to fixup can be unaligned.
+			 *
+			 * Use a memcpy for the architectures that do
+			 * not support unaligned accesses.
+			 */
+			memcpy(&adj_val, tree_val + poffset, sizeof(adj_val));
+
+			adj_val = cpu_to_fdt32(fdt32_to_cpu(adj_val) + delta);
+
+			ret = fdt_setprop_inplace_namelen_partial(fdto,
+								  tree_node,
+								  name,
+								  strlen(name),
+								  poffset,
+								  &adj_val,
+								  sizeof(adj_val));
+			if (ret == -FDT_ERR_NOSPACE)
+				return -FDT_ERR_BADOVERLAY;
+
+			if (ret)
+				return ret;
+		}
+	}
+
+	fdt_for_each_subnode(fixup_child, fdto, fixup_node) {
+		const char *fixup_child_name = fdt_get_name(fdto, fixup_child,
+							    NULL);
+		int tree_child;
+
+		tree_child = fdt_subnode_offset(fdto, tree_node,
+						fixup_child_name);
+		if (tree_child == -FDT_ERR_NOTFOUND)
+			return -FDT_ERR_BADOVERLAY;
+		if (tree_child < 0)
+			return tree_child;
+
+		ret = overlay_update_local_node_references(fdto,
+							   tree_child,
+							   fixup_child,
+							   delta);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * overlay_update_local_references - Adjust the overlay references
+ * @fdto: Device tree overlay blob
+ * @delta: Offset to shift the phandles of
+ *
+ * overlay_update_local_references() update all the phandles pointing
+ * to a node within the device tree overlay by adding a constant
+ * delta to not conflict with the base overlay.
+ *
+ * This is mainly used as part of a device tree application process,
+ * where you want the device tree overlays phandles to not conflict
+ * with the ones from the base device tree before merging them.
+ *
+ * returns:
+ *      0 on success
+ *      Negative error code on failure
+ */
+static int overlay_update_local_references(void *fdto, uint32_t delta)
+{
+	int fixups;
+
+	fixups = fdt_path_offset(fdto, "/__local_fixups__");
+	if (fixups < 0) {
+		/* There's no local phandles to adjust, bail out */
+		if (fixups == -FDT_ERR_NOTFOUND)
+			return 0;
+
+		return fixups;
+	}
+
+	/*
+	 * Update our local references from the root of the tree
+	 */
+	return overlay_update_local_node_references(fdto, 0, fixups,
+						    delta);
+}
+
+/**
+ * overlay_fixup_one_phandle - Set an overlay phandle to the base one
+ * @fdt: Base Device Tree blob
+ * @fdto: Device tree overlay blob
+ * @symbols_off: Node offset of the symbols node in the base device tree
+ * @path: Path to a node holding a phandle in the overlay
+ * @path_len: number of path characters to consider
+ * @name: Name of the property holding the phandle reference in the overlay
+ * @name_len: number of name characters to consider
+ * @poffset: Offset within the overlay property where the phandle is stored
+ * @label: Label of the node referenced by the phandle
+ *
+ * overlay_fixup_one_phandle() resolves an overlay phandle pointing to
+ * a node in the base device tree.
+ *
+ * This is part of the device tree overlay application process, when
+ * you want all the phandles in the overlay to point to the actual
+ * base dt nodes.
+ *
+ * returns:
+ *      0 on success
+ *      Negative error code on failure
+ */
+static int overlay_fixup_one_phandle(void *fdt, void *fdto,
+				     int symbols_off,
+				     const char *path, uint32_t path_len,
+				     const char *name, uint32_t name_len,
+				     int poffset, const char *label)
+{
+	const char *symbol_path;
+	uint32_t phandle;
+	fdt32_t phandle_prop;
+	int symbol_off, fixup_off;
+	int prop_len;
+
+	if (symbols_off < 0)
+		return symbols_off;
+
+	symbol_path = fdt_getprop(fdt, symbols_off, label,
+				  &prop_len);
+	if (!symbol_path)
+		return prop_len;
+
+	symbol_off = fdt_path_offset(fdt, symbol_path);
+	if (symbol_off < 0)
+		return symbol_off;
+
+	phandle = fdt_get_phandle(fdt, symbol_off);
+	if (!phandle)
+		return -FDT_ERR_NOTFOUND;
+
+	fixup_off = fdt_path_offset_namelen(fdto, path, path_len);
+	if (fixup_off == -FDT_ERR_NOTFOUND)
+		return -FDT_ERR_BADOVERLAY;
+	if (fixup_off < 0)
+		return fixup_off;
+
+	phandle_prop = cpu_to_fdt32(phandle);
+	return fdt_setprop_inplace_namelen_partial(fdto, fixup_off,
+						   name, name_len, poffset,
+						   &phandle_prop,
+						   sizeof(phandle_prop));
+}
+
+/**
+ * overlay_fixup_phandle - Set an overlay phandle to the base one
+ * @fdt: Base Device Tree blob
+ * @fdto: Device tree overlay blob
+ * @symbols_off: Node offset of the symbols node in the base device tree
+ * @property: Property offset in the overlay holding the list of fixups
+ *
+ * overlay_fixup_phandle() resolves all the overlay phandles pointed
+ * to in a __fixups__ property, and updates them to match the phandles
+ * in use in the base device tree.
+ *
+ * This is part of the device tree overlay application process, when
+ * you want all the phandles in the overlay to point to the actual
+ * base dt nodes.
+ *
+ * returns:
+ *      0 on success
+ *      Negative error code on failure
+ */
+static int overlay_fixup_phandle(void *fdt, void *fdto, int symbols_off,
+				 int property)
+{
+	const char *value;
+	const char *label;
+	int len;
+
+	value = fdt_getprop_by_offset(fdto, property,
+				      &label, &len);
+	if (!value) {
+		if (len == -FDT_ERR_NOTFOUND)
+			return -FDT_ERR_INTERNAL;
+
+		return len;
+	}
+
+	do {
+		const char *path, *name, *fixup_end;
+		const char *fixup_str = value;
+		uint32_t path_len, name_len;
+		uint32_t fixup_len;
+		char *sep, *endptr;
+		int poffset, ret;
+
+		fixup_end = memchr(value, '\0', len);
+		if (!fixup_end)
+			return -FDT_ERR_BADOVERLAY;
+		fixup_len = fixup_end - fixup_str;
+
+		len -= fixup_len + 1;
+		value += fixup_len + 1;
+
+		path = fixup_str;
+		sep = memchr(fixup_str, ':', fixup_len);
+		if (!sep || *sep != ':')
+			return -FDT_ERR_BADOVERLAY;
+
+		path_len = sep - path;
+		if (path_len == (fixup_len - 1))
+			return -FDT_ERR_BADOVERLAY;
+
+		fixup_len -= path_len + 1;
+		name = sep + 1;
+		sep = memchr(name, ':', fixup_len);
+		if (!sep || *sep != ':')
+			return -FDT_ERR_BADOVERLAY;
+
+		name_len = sep - name;
+		if (!name_len)
+			return -FDT_ERR_BADOVERLAY;
+
+		poffset = strtoul(sep + 1, &endptr, 10);
+		if ((*endptr != '\0') || (endptr <= (sep + 1)))
+			return -FDT_ERR_BADOVERLAY;
+
+		ret = overlay_fixup_one_phandle(fdt, fdto, symbols_off,
+						path, path_len, name, name_len,
+						poffset, label);
+		if (ret)
+			return ret;
+	} while (len > 0);
+
+	return 0;
+}
+
+/**
+ * overlay_fixup_phandles - Resolve the overlay phandles to the base
+ *                          device tree
+ * @fdt: Base Device Tree blob
+ * @fdto: Device tree overlay blob
+ *
+ * overlay_fixup_phandles() resolves all the overlay phandles pointing
+ * to nodes in the base device tree.
+ *
+ * This is one of the steps of the device tree overlay application
+ * process, when you want all the phandles in the overlay to point to
+ * the actual base dt nodes.
+ *
+ * returns:
+ *      0 on success
+ *      Negative error code on failure
+ */
+static int overlay_fixup_phandles(void *fdt, void *fdto)
+{
+	int fixups_off, symbols_off;
+	int property;
+
+	/* We can have overlays without any fixups */
+	fixups_off = fdt_path_offset(fdto, "/__fixups__");
+	if (fixups_off == -FDT_ERR_NOTFOUND)
+		return 0; /* nothing to do */
+	if (fixups_off < 0)
+		return fixups_off;
+
+	/* And base DTs without symbols */
+	symbols_off = fdt_path_offset(fdt, "/__symbols__");
+	if ((symbols_off < 0 && (symbols_off != -FDT_ERR_NOTFOUND)))
+		return symbols_off;
+
+	fdt_for_each_property_offset(property, fdto, fixups_off) {
+		int ret;
+
+		ret = overlay_fixup_phandle(fdt, fdto, symbols_off, property);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * overlay_apply_node - Merges a node into the base device tree
+ * @fdt: Base Device Tree blob
+ * @target: Node offset in the base device tree to apply the fragment to
+ * @fdto: Device tree overlay blob
+ * @node: Node offset in the overlay holding the changes to merge
+ *
+ * overlay_apply_node() merges a node into a target base device tree
+ * node pointed.
+ *
+ * This is part of the final step in the device tree overlay
+ * application process, when all the phandles have been adjusted and
+ * resolved and you just have to merge overlay into the base device
+ * tree.
+ *
+ * returns:
+ *      0 on success
+ *      Negative error code on failure
+ */
+static int overlay_apply_node(void *fdt, int target,
+			      void *fdto, int node)
+{
+	int property;
+	int subnode;
+
+	fdt_for_each_property_offset(property, fdto, node) {
+		const char *name;
+		const void *prop;
+		int prop_len;
+		int ret;
+
+		prop = fdt_getprop_by_offset(fdto, property, &name,
+					     &prop_len);
+		if (prop_len == -FDT_ERR_NOTFOUND)
+			return -FDT_ERR_INTERNAL;
+		if (prop_len < 0)
+			return prop_len;
+
+		ret = fdt_setprop(fdt, target, name, prop, prop_len);
+		if (ret)
+			return ret;
+	}
+
+	fdt_for_each_subnode(subnode, fdto, node) {
+		const char *name = fdt_get_name(fdto, subnode, NULL);
+		int nnode;
+		int ret;
+
+		nnode = fdt_add_subnode(fdt, target, name);
+		if (nnode == -FDT_ERR_EXISTS) {
+			nnode = fdt_subnode_offset(fdt, target, name);
+			if (nnode == -FDT_ERR_NOTFOUND)
+				return -FDT_ERR_INTERNAL;
+		}
+
+		if (nnode < 0)
+			return nnode;
+
+		ret = overlay_apply_node(fdt, nnode, fdto, subnode);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * overlay_merge - Merge an overlay into its base device tree
+ * @fdt: Base Device Tree blob
+ * @fdto: Device tree overlay blob
+ *
+ * overlay_merge() merges an overlay into its base device tree.
+ *
+ * This is the next to last step in the device tree overlay application
+ * process, when all the phandles have been adjusted and resolved and
+ * you just have to merge overlay into the base device tree.
+ *
+ * returns:
+ *      0 on success
+ *      Negative error code on failure
+ */
+static int overlay_merge(void *fdt, void *fdto)
+{
+	int fragment;
+
+	fdt_for_each_subnode(fragment, fdto, 0) {
+		int overlay;
+		int target;
+		int ret;
+
+		/*
+		 * Each fragments will have an __overlay__ node. If
+		 * they don't, it's not supposed to be merged
+		 */
+		overlay = fdt_subnode_offset(fdto, fragment, "__overlay__");
+		if (overlay == -FDT_ERR_NOTFOUND)
+			continue;
+
+		if (overlay < 0)
+			return overlay;
+
+		target = overlay_get_target(fdt, fdto, fragment, NULL);
+		if (target < 0)
+			return target;
+
+		ret = overlay_apply_node(fdt, target, fdto, overlay);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int get_path_len(const void *fdt, int nodeoffset)
+{
+	int len = 0, namelen;
+	const char *name;
+
+	FDT_CHECK_HEADER(fdt);
+
+	for (;;) {
+		name = fdt_get_name(fdt, nodeoffset, &namelen);
+		if (!name)
+			return namelen;
+
+		/* root? we're done */
+		if (namelen == 0)
+			break;
+
+		nodeoffset = fdt_parent_offset(fdt, nodeoffset);
+		if (nodeoffset < 0)
+			return nodeoffset;
+		len += namelen + 1;
+	}
+
+	/* in case of root pretend it's "/" */
+	if (len == 0)
+		len++;
+	return len;
+}
+
+/**
+ * overlay_symbol_update - Update the symbols of base tree after a merge
+ * @fdt: Base Device Tree blob
+ * @fdto: Device tree overlay blob
+ *
+ * overlay_symbol_update() updates the symbols of the base tree with the
+ * symbols of the applied overlay
+ *
+ * This is the last step in the device tree overlay application
+ * process, allowing the reference of overlay symbols by subsequent
+ * overlay operations.
+ *
+ * returns:
+ *      0 on success
+ *      Negative error code on failure
+ */
+static int overlay_symbol_update(void *fdt, void *fdto)
+{
+	int root_sym, ov_sym, prop, path_len, fragment, target;
+	int len, frag_name_len, ret, rel_path_len;
+	const char *s, *e;
+	const char *path;
+	const char *name;
+	const char *frag_name;
+	const char *rel_path;
+	const char *target_path;
+	char *buf;
+	void *p;
+
+	ov_sym = fdt_subnode_offset(fdto, 0, "__symbols__");
+
+	/* if no overlay symbols exist no problem */
+	if (ov_sym < 0)
+		return 0;
+
+	root_sym = fdt_subnode_offset(fdt, 0, "__symbols__");
+
+	/* it no root symbols exist we should create them */
+	if (root_sym == -FDT_ERR_NOTFOUND)
+		root_sym = fdt_add_subnode(fdt, 0, "__symbols__");
+
+	/* any error is fatal now */
+	if (root_sym < 0)
+		return root_sym;
+
+	/* iterate over each overlay symbol */
+	fdt_for_each_property_offset(prop, fdto, ov_sym) {
+		path = fdt_getprop_by_offset(fdto, prop, &name, &path_len);
+		if (!path)
+			return path_len;
+
+		/* verify it's a string property (terminated by a single \0) */
+		if (path_len < 1 || memchr(path, '\0', path_len) != &path[path_len - 1])
+			return -FDT_ERR_BADVALUE;
+
+		/* keep end marker to avoid strlen() */
+		e = path + path_len;
+
+		/* format: /<fragment-name>/__overlay__/<relative-subnode-path> */
+
+		if (*path != '/')
+			return -FDT_ERR_BADVALUE;
+
+		/* get fragment name first */
+		s = strchr(path + 1, '/');
+		if (!s)
+			return -FDT_ERR_BADOVERLAY;
+
+		frag_name = path + 1;
+		frag_name_len = s - path - 1;
+
+		/* verify format; safe since "s" lies in \0 terminated prop */
+		len = sizeof("/__overlay__/") - 1;
+		if ((e - s) < len || memcmp(s, "/__overlay__/", len))
+			return -FDT_ERR_BADOVERLAY;
+
+		rel_path = s + len;
+		rel_path_len = e - rel_path;
+
+		/* find the fragment index in which the symbol lies */
+		ret = fdt_subnode_offset_namelen(fdto, 0, frag_name,
+					       frag_name_len);
+		/* not found? */
+		if (ret < 0)
+			return -FDT_ERR_BADOVERLAY;
+		fragment = ret;
+
+		/* an __overlay__ subnode must exist */
+		ret = fdt_subnode_offset(fdto, fragment, "__overlay__");
+		if (ret < 0)
+			return -FDT_ERR_BADOVERLAY;
+
+		/* get the target of the fragment */
+		ret = overlay_get_target(fdt, fdto, fragment, &target_path);
+		if (ret < 0)
+			return ret;
+		target = ret;
+
+		/* if we have a target path use */
+		if (!target_path) {
+			ret = get_path_len(fdt, target);
+			if (ret < 0)
+				return ret;
+			len = ret;
+		} else {
+			len = strlen(target_path);
+		}
+
+		ret = fdt_setprop_placeholder(fdt, root_sym, name,
+				len + (len > 1) + rel_path_len + 1, &p);
+		if (ret < 0)
+			return ret;
+
+		if (!target_path) {
+			/* again in case setprop_placeholder changed it */
+			ret = overlay_get_target(fdt, fdto, fragment, &target_path);
+			if (ret < 0)
+				return ret;
+			target = ret;
+		}
+
+		buf = p;
+		if (len > 1) { /* target is not root */
+			if (!target_path) {
+				ret = fdt_get_path(fdt, target, buf, len + 1);
+				if (ret < 0)
+					return ret;
+			} else
+				memcpy(buf, target_path, len + 1);
+
+		} else
+			len--;
+
+		buf[len] = '/';
+		memcpy(buf + len + 1, rel_path, rel_path_len);
+		buf[len + 1 + rel_path_len] = '\0';
+	}
+
+	return 0;
+}
+
+int fdt_overlay_apply(void *fdt, void *fdto)
+{
+	uint32_t delta = fdt_get_max_phandle(fdt);
+	int ret;
+
+	FDT_CHECK_HEADER(fdt);
+	FDT_CHECK_HEADER(fdto);
+
+	ret = overlay_adjust_local_phandles(fdto, delta);
+	if (ret)
+		goto err;
+
+	ret = overlay_update_local_references(fdto, delta);
+	if (ret)
+		goto err;
+
+	ret = overlay_fixup_phandles(fdt, fdto);
+	if (ret)
+		goto err;
+
+	ret = overlay_merge(fdt, fdto);
+	if (ret)
+		goto err;
+
+	ret = overlay_symbol_update(fdt, fdto);
+	if (ret)
+		goto err;
+
+	/*
+	 * The overlay has been damaged, erase its magic.
+	 */
+	fdt_set_magic(fdto, ~0);
+
+	return 0;
+
+err:
+	/*
+	 * The overlay might have been damaged, erase its magic.
+	 */
+	fdt_set_magic(fdto, ~0);
+
+	/*
+	 * The base device tree might have been damaged, erase its
+	 * magic.
+	 */
+	fdt_set_magic(fdt, ~0);
+
+	return ret;
+}
diff --git a/core/lib/libfdt/fdt_ro.c b/core/lib/libfdt/fdt_ro.c
index 34110da0..f66da3d3 100644
--- a/core/lib/libfdt/fdt_ro.c
+++ b/core/lib/libfdt/fdt_ro.c
@@ -56,12 +56,13 @@
 
 #include "libfdt_internal.h"
 
-static int _fdt_nodename_eq(const void *fdt, int offset,
+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);
+	int olen;
+	const char *p = fdt_get_name(fdt, offset, &olen);
 
-	if (! p)
+	if (!p || olen < len)
 		/* short match */
 		return 0;
 
@@ -81,7 +82,7 @@ const char *fdt_string(const void *fdt, int stroffset)
 	return (const char *)fdt + fdt_off_dt_strings(fdt) + stroffset;
 }
 
-static int _fdt_string_eq(const void *fdt, int stroffset,
+static int fdt_string_eq_(const void *fdt, int stroffset,
 			  const char *s, int len)
 {
 	const char *p = fdt_string(fdt, stroffset);
@@ -89,11 +90,37 @@ static int _fdt_string_eq(const void *fdt, int stroffset,
 	return (strlen(p) == len) && (memcmp(p, s, len) == 0);
 }
 
+uint32_t fdt_get_max_phandle(const void *fdt)
+{
+	uint32_t max_phandle = 0;
+	int offset;
+
+	for (offset = fdt_next_node(fdt, -1, NULL);;
+	     offset = fdt_next_node(fdt, offset, NULL)) {
+		uint32_t phandle;
+
+		if (offset == -FDT_ERR_NOTFOUND)
+			return max_phandle;
+
+		if (offset < 0)
+			return (uint32_t)-1;
+
+		phandle = fdt_get_phandle(fdt, offset);
+		if (phandle == (uint32_t)-1)
+			continue;
+
+		if (phandle > max_phandle)
+			max_phandle = phandle;
+	}
+
+	return 0;
+}
+
 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);
+	*address = fdt64_to_cpu(fdt_mem_rsv_(fdt, n)->address);
+	*size = fdt64_to_cpu(fdt_mem_rsv_(fdt, n)->size);
 	return 0;
 }
 
@@ -101,12 +128,12 @@ int fdt_num_mem_rsv(const void *fdt)
 {
 	int i = 0;
 
-	while (fdt64_to_cpu(_fdt_mem_rsv(fdt, i)->size) != 0)
+	while (fdt64_to_cpu(fdt_mem_rsv_(fdt, i)->size) != 0)
 		i++;
 	return i;
 }
 
-static int _nextprop(const void *fdt, int offset)
+static int nextprop_(const void *fdt, int offset)
 {
 	uint32_t tag;
 	int nextoffset;
@@ -141,7 +168,7 @@ int fdt_subnode_offset_namelen(const void *fdt, int offset,
 	     (offset >= 0) && (depth >= 0);
 	     offset = fdt_next_node(fdt, offset, &depth))
 		if ((depth == 1)
-		    && _fdt_nodename_eq(fdt, offset, name, namelen))
+		    && fdt_nodename_eq_(fdt, offset, name, namelen))
 			return offset;
 
 	if (depth < 0)
@@ -155,9 +182,9 @@ int fdt_subnode_offset(const void *fdt, int parentoffset,
 	return fdt_subnode_offset_namelen(fdt, parentoffset, name, strlen(name));
 }
 
-int fdt_path_offset(const void *fdt, const char *path)
+int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen)
 {
-	const char *end = path + strlen(path);
+	const char *end = path + namelen;
 	const char *p = path;
 	int offset = 0;
 
@@ -165,7 +192,7 @@ int fdt_path_offset(const void *fdt, const char *path)
 
 	/* see if we have an alias */
 	if (*path != '/') {
-		const char *q = strchr(path, '/');
+		const char *q = memchr(path, '/', end - p);
 
 		if (!q)
 			q = end;
@@ -178,14 +205,15 @@ int fdt_path_offset(const void *fdt, const char *path)
 		p = q;
 	}
 
-	while (*p) {
+	while (p < end) {
 		const char *q;
 
-		while (*p == '/')
+		while (*p == '/') {
 			p++;
-		if (! *p)
-			return offset;
-		q = strchr(p, '/');
+			if (p == end)
+				return offset;
+		}
+		q = memchr(p, '/', end - p);
 		if (! q)
 			q = end;
 
@@ -199,19 +227,42 @@ int fdt_path_offset(const void *fdt, const char *path)
 	return offset;
 }
 
+int fdt_path_offset(const void *fdt, const char *path)
+{
+	return fdt_path_offset_namelen(fdt, path, strlen(path));
+}
+
 const char *fdt_get_name(const void *fdt, int nodeoffset, int *len)
 {
-	const struct fdt_node_header *nh = _fdt_offset_ptr(fdt, nodeoffset);
+	const struct fdt_node_header *nh = fdt_offset_ptr_(fdt, nodeoffset);
+	const char *nameptr;
 	int err;
 
 	if (((err = fdt_check_header(fdt)) != 0)
-	    || ((err = _fdt_check_node_offset(fdt, nodeoffset)) < 0))
+	    || ((err = fdt_check_node_offset_(fdt, nodeoffset)) < 0))
 			goto fail;
 
+	nameptr = nh->name;
+
+	if (fdt_version(fdt) < 0x10) {
+		/*
+		 * For old FDT versions, match the naming conventions of V16:
+		 * give only the leaf name (after all /). The actual tree
+		 * contents are loosely checked.
+		 */
+		const char *leaf;
+		leaf = strrchr(nameptr, '/');
+		if (leaf == NULL) {
+			err = -FDT_ERR_BADSTRUCTURE;
+			goto fail;
+		}
+		nameptr = leaf+1;
+	}
+
 	if (len)
-		*len = strlen(nh->name);
+		*len = strlen(nameptr);
 
-	return nh->name;
+	return nameptr;
 
  fail:
 	if (len)
@@ -223,34 +274,34 @@ int fdt_first_property_offset(const void *fdt, int nodeoffset)
 {
 	int offset;
 
-	if ((offset = _fdt_check_node_offset(fdt, nodeoffset)) < 0)
+	if ((offset = fdt_check_node_offset_(fdt, nodeoffset)) < 0)
 		return offset;
 
-	return _nextprop(fdt, offset);
+	return nextprop_(fdt, offset);
 }
 
 int fdt_next_property_offset(const void *fdt, int offset)
 {
-	if ((offset = _fdt_check_prop_offset(fdt, offset)) < 0)
+	if ((offset = fdt_check_prop_offset_(fdt, offset)) < 0)
 		return offset;
 
-	return _nextprop(fdt, offset);
+	return nextprop_(fdt, offset);
 }
 
-const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
-						      int offset,
-						      int *lenp)
+static const struct fdt_property *fdt_get_property_by_offset_(const void *fdt,
+						              int offset,
+						              int *lenp)
 {
 	int err;
 	const struct fdt_property *prop;
 
-	if ((err = _fdt_check_prop_offset(fdt, offset)) < 0) {
+	if ((err = fdt_check_prop_offset_(fdt, offset)) < 0) {
 		if (lenp)
 			*lenp = err;
 		return NULL;
 	}
 
-	prop = _fdt_offset_ptr(fdt, offset);
+	prop = fdt_offset_ptr_(fdt, offset);
 
 	if (lenp)
 		*lenp = fdt32_to_cpu(prop->len);
@@ -258,23 +309,44 @@ const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
 	return prop;
 }
 
-const struct fdt_property *fdt_get_property_namelen(const void *fdt,
-						    int offset,
-						    const char *name,
-						    int namelen, int *lenp)
+const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
+						      int offset,
+						      int *lenp)
+{
+	/* Prior to version 16, properties may need realignment
+	 * and this API does not work. fdt_getprop_*() will, however. */
+
+	if (fdt_version(fdt) < 0x10) {
+		if (lenp)
+			*lenp = -FDT_ERR_BADVERSION;
+		return NULL;
+	}
+
+	return fdt_get_property_by_offset_(fdt, offset, lenp);
+}
+
+static const struct fdt_property *fdt_get_property_namelen_(const void *fdt,
+						            int offset,
+						            const char *name,
+						            int namelen,
+							    int *lenp,
+							    int *poffset)
 {
 	for (offset = fdt_first_property_offset(fdt, offset);
 	     (offset >= 0);
 	     (offset = fdt_next_property_offset(fdt, offset))) {
 		const struct fdt_property *prop;
 
-		if (!(prop = fdt_get_property_by_offset(fdt, offset, lenp))) {
+		if (!(prop = fdt_get_property_by_offset_(fdt, offset, lenp))) {
 			offset = -FDT_ERR_INTERNAL;
 			break;
 		}
-		if (_fdt_string_eq(fdt, fdt32_to_cpu(prop->nameoff),
-				   name, namelen))
+		if (fdt_string_eq_(fdt, fdt32_to_cpu(prop->nameoff),
+				   name, namelen)) {
+			if (poffset)
+				*poffset = offset;
 			return prop;
+		}
 	}
 
 	if (lenp)
@@ -282,6 +354,25 @@ const struct fdt_property *fdt_get_property_namelen(const void *fdt,
 	return NULL;
 }
 
+
+const struct fdt_property *fdt_get_property_namelen(const void *fdt,
+						    int offset,
+						    const char *name,
+						    int namelen, int *lenp)
+{
+	/* Prior to version 16, properties may need realignment
+	 * and this API does not work. fdt_getprop_*() will, however. */
+	if (fdt_version(fdt) < 0x10) {
+		if (lenp)
+			*lenp = -FDT_ERR_BADVERSION;
+		return NULL;
+	}
+
+	return fdt_get_property_namelen_(fdt, offset, name, namelen, lenp,
+					 NULL);
+}
+
+
 const struct fdt_property *fdt_get_property(const void *fdt,
 					    int nodeoffset,
 					    const char *name, int *lenp)
@@ -293,12 +384,18 @@ const struct fdt_property *fdt_get_property(const void *fdt,
 const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
 				const char *name, int namelen, int *lenp)
 {
+	int poffset;
 	const struct fdt_property *prop;
 
-	prop = fdt_get_property_namelen(fdt, nodeoffset, name, namelen, lenp);
-	if (! prop)
+	prop = fdt_get_property_namelen_(fdt, nodeoffset, name, namelen, lenp,
+					 &poffset);
+	if (!prop)
 		return NULL;
 
+	/* Handle realignment */
+	if (fdt_version(fdt) < 0x10 && (poffset + sizeof(*prop)) % 8 &&
+	    fdt32_to_cpu(prop->len) >= 8)
+		return prop->data + 4;
 	return prop->data;
 }
 
@@ -307,11 +404,16 @@ const void *fdt_getprop_by_offset(const void *fdt, int offset,
 {
 	const struct fdt_property *prop;
 
-	prop = fdt_get_property_by_offset(fdt, offset, lenp);
+	prop = fdt_get_property_by_offset_(fdt, offset, lenp);
 	if (!prop)
 		return NULL;
 	if (namep)
 		*namep = fdt_string(fdt, fdt32_to_cpu(prop->nameoff));
+
+	/* Handle realignment */
+	if (fdt_version(fdt) < 0x10 && (offset + sizeof(*prop)) % 8 &&
+	    fdt32_to_cpu(prop->len) >= 8)
+		return prop->data + 4;
 	return prop->data;
 }
 
@@ -533,6 +635,106 @@ int fdt_stringlist_contains(const char *strlist, int listlen, const char *str)
 	return 0;
 }
 
+int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property)
+{
+	const char *list, *end;
+	int length, count = 0;
+
+	list = fdt_getprop(fdt, nodeoffset, property, &length);
+	if (!list)
+		return length;
+
+	end = list + length;
+
+	while (list < end) {
+		length = strnlen(list, end - list) + 1;
+
+		/* Abort if the last string isn't properly NUL-terminated. */
+		if (list + length > end)
+			return -FDT_ERR_BADVALUE;
+
+		list += length;
+		count++;
+	}
+
+	return count;
+}
+
+int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
+			  const char *string)
+{
+	int length, len, idx = 0;
+	const char *list, *end;
+
+	list = fdt_getprop(fdt, nodeoffset, property, &length);
+	if (!list)
+		return length;
+
+	len = strlen(string) + 1;
+	end = list + length;
+
+	while (list < end) {
+		length = strnlen(list, end - list) + 1;
+
+		/* Abort if the last string isn't properly NUL-terminated. */
+		if (list + length > end)
+			return -FDT_ERR_BADVALUE;
+
+		if (length == len && memcmp(list, string, length) == 0)
+			return idx;
+
+		list += length;
+		idx++;
+	}
+
+	return -FDT_ERR_NOTFOUND;
+}
+
+const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
+			       const char *property, int idx,
+			       int *lenp)
+{
+	const char *list, *end;
+	int length;
+
+	list = fdt_getprop(fdt, nodeoffset, property, &length);
+	if (!list) {
+		if (lenp)
+			*lenp = length;
+
+		return NULL;
+	}
+
+	end = list + length;
+
+	while (list < end) {
+		length = strnlen(list, end - list) + 1;
+
+		/* Abort if the last string isn't properly NUL-terminated. */
+		if (list + length > end) {
+			if (lenp)
+				*lenp = -FDT_ERR_BADVALUE;
+
+			return NULL;
+		}
+
+		if (idx == 0) {
+			if (lenp)
+				*lenp = length - 1;
+
+			return list;
+		}
+
+		list += length;
+		idx--;
+	}
+
+	if (lenp)
+		*lenp = -FDT_ERR_NOTFOUND;
+
+	return NULL;
+}
+
 int fdt_node_check_compatible(const void *fdt, int nodeoffset,
 			      const char *compatible)
 {
@@ -542,10 +744,8 @@ int fdt_node_check_compatible(const void *fdt, int nodeoffset,
 	prop = fdt_getprop(fdt, nodeoffset, "compatible", &len);
 	if (!prop)
 		return len;
-	if (fdt_stringlist_contains(prop, len, compatible))
-		return 0;
-	else
-		return 1;
+
+	return !fdt_stringlist_contains(prop, len, compatible);
 }
 
 int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
diff --git a/core/lib/libfdt/fdt_rw.c b/core/lib/libfdt/fdt_rw.c
index 1785a510..28872c6b 100644
--- a/core/lib/libfdt/fdt_rw.c
+++ b/core/lib/libfdt/fdt_rw.c
@@ -56,8 +56,8 @@
 
 #include "libfdt_internal.h"
 
-static int _fdt_blocks_misordered(const void *fdt,
-			      int mem_rsv_size, int struct_size)
+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) <
@@ -68,13 +68,13 @@ static int _fdt_blocks_misordered(const void *fdt,
 		    (fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt)));
 }
 
-static int _fdt_rw_check_header(void *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),
+	if (fdt_blocks_misordered_(fdt, sizeof(struct fdt_reserve_entry),
 				   fdt_size_dt_struct(fdt)))
 		return -FDT_ERR_BADLAYOUT;
 	if (fdt_version(fdt) > 17)
@@ -85,35 +85,37 @@ static int _fdt_rw_check_header(void *fdt)
 
 #define FDT_RW_CHECK_HEADER(fdt) \
 	{ \
-		int __err; \
-		if ((__err = _fdt_rw_check_header(fdt)) != 0) \
-			return __err; \
+		int err_; \
+		if ((err_ = fdt_rw_check_header_(fdt)) != 0) \
+			return err_; \
 	}
 
-static inline int _fdt_data_size(void *fdt)
+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)
+static int fdt_splice_(void *fdt, void *splicepoint, int oldlen, int newlen)
 {
 	char *p = splicepoint;
-	char *end = (char *)fdt + _fdt_data_size(fdt);
+	char *end = (char *)fdt + fdt_data_size_(fdt);
 
 	if (((p + oldlen) < p) || ((p + oldlen) > end))
 		return -FDT_ERR_BADOFFSET;
+	if ((p < (char *)fdt) || ((end - oldlen + newlen) < (char *)fdt))
+		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,
+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));
+	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);
@@ -121,13 +123,13 @@ static int _fdt_splice_mem_rsv(void *fdt, struct fdt_reserve_entry *p,
 	return 0;
 }
 
-static int _fdt_splice_struct(void *fdt, void *p,
+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)))
+	if ((err = fdt_splice_(fdt, p, oldlen, newlen)))
 		return err;
 
 	fdt_set_size_dt_struct(fdt, fdt_size_dt_struct(fdt) + delta);
@@ -135,20 +137,20 @@ static int _fdt_splice_struct(void *fdt, void *p,
 	return 0;
 }
 
-static int _fdt_splice_string(void *fdt, int newlen)
+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)))
+	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)
+static int fdt_find_add_string_(void *fdt, const char *s)
 {
 	char *strtab = (char *)fdt + fdt_off_dt_strings(fdt);
 	const char *p;
@@ -156,13 +158,13 @@ static int _fdt_find_add_string(void *fdt, const char *s)
 	int len = strlen(s) + 1;
 	int err;
 
-	p = _fdt_find_string(strtab, fdt_size_dt_strings(fdt), s);
+	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);
+	err = fdt_splice_string_(fdt, len);
 	if (err)
 		return err;
 
@@ -177,8 +179,8 @@ int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size)
 
 	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);
+	re = fdt_mem_rsv_w_(fdt, fdt_num_mem_rsv(fdt));
+	err = fdt_splice_mem_rsv_(fdt, re, 0, 1);
 	if (err)
 		return err;
 
@@ -189,31 +191,27 @@ int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size)
 
 int fdt_del_mem_rsv(void *fdt, int n)
 {
-	struct fdt_reserve_entry *re = _fdt_mem_rsv_w(fdt, n);
-	int err;
+	struct fdt_reserve_entry *re = fdt_mem_rsv_w_(fdt, n);
 
 	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;
+	return fdt_splice_mem_rsv_(fdt, re, 1, 0);
 }
 
-static int _fdt_resize_property(void *fdt, int nodeoffset, const char *name,
+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))
+	if (!*prop)
 		return oldlen;
 
-	if ((err = _fdt_splice_struct(fdt, (*prop)->data, FDT_TAGALIGN(oldlen),
+	if ((err = fdt_splice_struct_(fdt, (*prop)->data, FDT_TAGALIGN(oldlen),
 				      FDT_TAGALIGN(len))))
 		return err;
 
@@ -221,7 +219,7 @@ static int _fdt_resize_property(void *fdt, int nodeoffset, const char *name,
 	return 0;
 }
 
-static int _fdt_add_property(void *fdt, int nodeoffset, const char *name,
+static int fdt_add_property_(void *fdt, int nodeoffset, const char *name,
 			     int len, struct fdt_property **prop)
 {
 	int proplen;
@@ -229,17 +227,17 @@ static int _fdt_add_property(void *fdt, int nodeoffset, const char *name,
 	int namestroff;
 	int err;
 
-	if ((nextoffset = _fdt_check_node_offset(fdt, nodeoffset)) < 0)
+	if ((nextoffset = fdt_check_node_offset_(fdt, nodeoffset)) < 0)
 		return nextoffset;
 
-	namestroff = _fdt_find_add_string(fdt, name);
+	namestroff = fdt_find_add_string_(fdt, name);
 	if (namestroff < 0)
 		return namestroff;
 
-	*prop = _fdt_offset_ptr_w(fdt, nextoffset);
+	*prop = fdt_offset_ptr_w_(fdt, nextoffset);
 	proplen = sizeof(**prop) + FDT_TAGALIGN(len);
 
-	err = _fdt_splice_struct(fdt, *prop, 0, proplen);
+	err = fdt_splice_struct_(fdt, *prop, 0, proplen);
 	if (err)
 		return err;
 
@@ -263,7 +261,7 @@ int fdt_set_name(void *fdt, int nodeoffset, const char *name)
 
 	newlen = strlen(name);
 
-	err = _fdt_splice_struct(fdt, namep, FDT_TAGALIGN(oldlen+1),
+	err = fdt_splice_struct_(fdt, namep, FDT_TAGALIGN(oldlen+1),
 				 FDT_TAGALIGN(newlen+1));
 	if (err)
 		return err;
@@ -272,22 +270,36 @@ int fdt_set_name(void *fdt, int nodeoffset, const char *name)
 	return 0;
 }
 
-int fdt_setprop(void *fdt, int nodeoffset, const char *name,
-		const void *val, int len)
+int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
+			    int len, void **prop_data)
 {
 	struct fdt_property *prop;
 	int err;
 
 	FDT_RW_CHECK_HEADER(fdt);
 
-	err = _fdt_resize_property(fdt, nodeoffset, name, len, &prop);
+	err = fdt_resize_property_(fdt, nodeoffset, name, len, &prop);
 	if (err == -FDT_ERR_NOTFOUND)
-		err = _fdt_add_property(fdt, nodeoffset, name, len, &prop);
+		err = fdt_add_property_(fdt, nodeoffset, name, len, &prop);
+	if (err)
+		return err;
+
+	*prop_data = prop->data;
+	return 0;
+}
+
+int fdt_setprop(void *fdt, int nodeoffset, const char *name,
+		const void *val, int len)
+{
+	void *prop_data;
+	int err;
+
+	err = fdt_setprop_placeholder(fdt, nodeoffset, name, len, &prop_data);
 	if (err)
 		return err;
 
 	if (len)
-		memcpy(prop->data, val, len);
+		memcpy(prop_data, val, len);
 	return 0;
 }
 
@@ -302,7 +314,7 @@ int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
 	prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen);
 	if (prop) {
 		newlen = len + oldlen;
-		err = _fdt_splice_struct(fdt, prop->data,
+		err = fdt_splice_struct_(fdt, prop->data,
 					 FDT_TAGALIGN(oldlen),
 					 FDT_TAGALIGN(newlen));
 		if (err)
@@ -310,7 +322,7 @@ int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
 		prop->len = cpu_to_fdt32(newlen);
 		memcpy(prop->data + oldlen, val, len);
 	} else {
-		err = _fdt_add_property(fdt, nodeoffset, name, len, &prop);
+		err = fdt_add_property_(fdt, nodeoffset, name, len, &prop);
 		if (err)
 			return err;
 		memcpy(prop->data, val, len);
@@ -326,11 +338,11 @@ int fdt_delprop(void *fdt, int nodeoffset, const char *name)
 	FDT_RW_CHECK_HEADER(fdt);
 
 	prop = fdt_get_property_w(fdt, nodeoffset, name, &len);
-	if (! prop)
+	if (!prop)
 		return len;
 
 	proplen = sizeof(*prop) + FDT_TAGALIGN(len);
-	return _fdt_splice_struct(fdt, prop, proplen, 0);
+	return fdt_splice_struct_(fdt, prop, proplen, 0);
 }
 
 int fdt_add_subnode_namelen(void *fdt, int parentoffset,
@@ -358,10 +370,10 @@ int fdt_add_subnode_namelen(void *fdt, int parentoffset,
 		tag = fdt_next_tag(fdt, offset, &nextoffset);
 	} while ((tag == FDT_PROP) || (tag == FDT_NOP));
 
-	nh = _fdt_offset_ptr_w(fdt, offset);
+	nh = fdt_offset_ptr_w_(fdt, offset);
 	nodelen = sizeof(*nh) + FDT_TAGALIGN(namelen+1) + FDT_TAGSIZE;
 
-	err = _fdt_splice_struct(fdt, nh, 0, nodelen);
+	err = fdt_splice_struct_(fdt, nh, 0, nodelen);
 	if (err)
 		return err;
 
@@ -385,15 +397,15 @@ int fdt_del_node(void *fdt, int nodeoffset)
 
 	FDT_RW_CHECK_HEADER(fdt);
 
-	endoffset = _fdt_node_end_offset(fdt, nodeoffset);
+	endoffset = fdt_node_end_offset_(fdt, nodeoffset);
 	if (endoffset < 0)
 		return endoffset;
 
-	return _fdt_splice_struct(fdt, _fdt_offset_ptr_w(fdt, nodeoffset),
+	return fdt_splice_struct_(fdt, fdt_offset_ptr_w_(fdt, nodeoffset),
 				  endoffset - nodeoffset, 0);
 }
 
-static void _fdt_packblocks(const char *old, char *new,
+static void fdt_packblocks_(const char *old, char *new,
 			    int mem_rsv_size, int struct_size)
 {
 	int mem_rsv_off, struct_off, strings_off;
@@ -439,7 +451,7 @@ int fdt_open_into(const void *fdt, void *buf, int bufsize)
 			return struct_size;
 	}
 
-	if (!_fdt_blocks_misordered(fdt, mem_rsv_size, struct_size)) {
+	if (!fdt_blocks_misordered_(fdt, mem_rsv_size, struct_size)) {
 		/* no further work necessary */
 		err = fdt_move(fdt, buf, bufsize);
 		if (err)
@@ -467,7 +479,7 @@ int fdt_open_into(const void *fdt, void *buf, int bufsize)
 			return -FDT_ERR_NOSPACE;
 	}
 
-	_fdt_packblocks(fdt, tmp, mem_rsv_size, struct_size);
+	fdt_packblocks_(fdt, tmp, mem_rsv_size, struct_size);
 	memmove(buf, tmp, newsize);
 
 	fdt_set_magic(buf, FDT_MAGIC);
@@ -487,8 +499,8 @@ int fdt_pack(void *fdt)
 
 	mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
 		* sizeof(struct fdt_reserve_entry);
-	_fdt_packblocks(fdt, fdt, mem_rsv_size, fdt_size_dt_struct(fdt));
-	fdt_set_totalsize(fdt, _fdt_data_size(fdt));
+	fdt_packblocks_(fdt, fdt, mem_rsv_size, fdt_size_dt_struct(fdt));
+	fdt_set_totalsize(fdt, fdt_data_size_(fdt));
 
 	return 0;
 }
diff --git a/core/lib/libfdt/fdt_strerror.c b/core/lib/libfdt/fdt_strerror.c
index 50e88451..dccf2265 100644
--- a/core/lib/libfdt/fdt_strerror.c
+++ b/core/lib/libfdt/fdt_strerror.c
@@ -70,6 +70,7 @@ static struct fdt_errtabent fdt_errtable[] = {
 
 	FDT_ERRTABENT(FDT_ERR_BADOFFSET),
 	FDT_ERRTABENT(FDT_ERR_BADPATH),
+	FDT_ERRTABENT(FDT_ERR_BADPHANDLE),
 	FDT_ERRTABENT(FDT_ERR_BADSTATE),
 
 	FDT_ERRTABENT(FDT_ERR_TRUNCATED),
@@ -77,6 +78,11 @@ static struct fdt_errtabent fdt_errtable[] = {
 	FDT_ERRTABENT(FDT_ERR_BADVERSION),
 	FDT_ERRTABENT(FDT_ERR_BADSTRUCTURE),
 	FDT_ERRTABENT(FDT_ERR_BADLAYOUT),
+	FDT_ERRTABENT(FDT_ERR_INTERNAL),
+	FDT_ERRTABENT(FDT_ERR_BADNCELLS),
+	FDT_ERRTABENT(FDT_ERR_BADVALUE),
+	FDT_ERRTABENT(FDT_ERR_BADOVERLAY),
+	FDT_ERRTABENT(FDT_ERR_NOPHANDLES),
 };
 #define FDT_ERRTABSIZE	(sizeof(fdt_errtable) / sizeof(fdt_errtable[0]))
 
diff --git a/core/lib/libfdt/fdt_sw.c b/core/lib/libfdt/fdt_sw.c
index d1dcc895..dcd0ebd8 100644
--- a/core/lib/libfdt/fdt_sw.c
+++ b/core/lib/libfdt/fdt_sw.c
@@ -56,7 +56,7 @@
 
 #include "libfdt_internal.h"
 
-static int _fdt_sw_check_header(void *fdt)
+static int fdt_sw_check_header_(void *fdt)
 {
 	if (fdt_magic(fdt) != FDT_SW_MAGIC)
 		return -FDT_ERR_BADMAGIC;
@@ -67,11 +67,11 @@ static int _fdt_sw_check_header(void *fdt)
 #define FDT_SW_CHECK_HEADER(fdt) \
 	{ \
 		int err; \
-		if ((err = _fdt_sw_check_header(fdt)) != 0) \
+		if ((err = fdt_sw_check_header_(fdt)) != 0) \
 			return err; \
 	}
 
-static void *_fdt_grab_space(void *fdt, size_t len)
+static void *fdt_grab_space_(void *fdt, size_t len)
 {
 	int offset = fdt_size_dt_struct(fdt);
 	int spaceleft;
@@ -83,7 +83,7 @@ static void *_fdt_grab_space(void *fdt, size_t len)
 		return NULL;
 
 	fdt_set_size_dt_struct(fdt, offset + len);
-	return _fdt_offset_ptr_w(fdt, offset);
+	return fdt_offset_ptr_w_(fdt, offset);
 }
 
 int fdt_create(void *buf, int bufsize)
@@ -175,7 +175,7 @@ int fdt_begin_node(void *fdt, const char *name)
 
 	FDT_SW_CHECK_HEADER(fdt);
 
-	nh = _fdt_grab_space(fdt, sizeof(*nh) + FDT_TAGALIGN(namelen));
+	nh = fdt_grab_space_(fdt, sizeof(*nh) + FDT_TAGALIGN(namelen));
 	if (! nh)
 		return -FDT_ERR_NOSPACE;
 
@@ -190,7 +190,7 @@ int fdt_end_node(void *fdt)
 
 	FDT_SW_CHECK_HEADER(fdt);
 
-	en = _fdt_grab_space(fdt, FDT_TAGSIZE);
+	en = fdt_grab_space_(fdt, FDT_TAGSIZE);
 	if (! en)
 		return -FDT_ERR_NOSPACE;
 
@@ -198,7 +198,7 @@ int fdt_end_node(void *fdt)
 	return 0;
 }
 
-static int _fdt_find_add_string(void *fdt, const char *s)
+static int fdt_find_add_string_(void *fdt, const char *s)
 {
 	char *strtab = (char *)fdt + fdt_totalsize(fdt);
 	const char *p;
@@ -206,7 +206,7 @@ static int _fdt_find_add_string(void *fdt, const char *s)
 	int len = strlen(s) + 1;
 	int struct_top, offset;
 
-	p = _fdt_find_string(strtab - strtabsize, strtabsize, s);
+	p = fdt_find_string_(strtab - strtabsize, strtabsize, s);
 	if (p)
 		return p - strtab;
 
@@ -221,25 +221,37 @@ static int _fdt_find_add_string(void *fdt, const char *s)
 	return offset;
 }
 
-int fdt_property(void *fdt, const char *name, const void *val, int len)
+int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp)
 {
 	struct fdt_property *prop;
 	int nameoff;
 
 	FDT_SW_CHECK_HEADER(fdt);
 
-	nameoff = _fdt_find_add_string(fdt, name);
+	nameoff = fdt_find_add_string_(fdt, name);
 	if (nameoff == 0)
 		return -FDT_ERR_NOSPACE;
 
-	prop = _fdt_grab_space(fdt, sizeof(*prop) + FDT_TAGALIGN(len));
+	prop = fdt_grab_space_(fdt, sizeof(*prop) + FDT_TAGALIGN(len));
 	if (! prop)
 		return -FDT_ERR_NOSPACE;
 
 	prop->tag = cpu_to_fdt32(FDT_PROP);
 	prop->nameoff = cpu_to_fdt32(nameoff);
 	prop->len = cpu_to_fdt32(len);
-	memcpy(prop->data, val, len);
+	*valp = prop->data;
+	return 0;
+}
+
+int fdt_property(void *fdt, const char *name, const void *val, int len)
+{
+	void *ptr;
+	int ret;
+
+	ret = fdt_property_placeholder(fdt, name, len, &ptr);
+	if (ret)
+		return ret;
+	memcpy(ptr, val, len);
 	return 0;
 }
 
@@ -254,7 +266,7 @@ int fdt_finish(void *fdt)
 	FDT_SW_CHECK_HEADER(fdt);
 
 	/* Add terminator */
-	end = _fdt_grab_space(fdt, sizeof(*end));
+	end = fdt_grab_space_(fdt, sizeof(*end));
 	if (! end)
 		return -FDT_ERR_NOSPACE;
 	*end = cpu_to_fdt32(FDT_END);
@@ -270,7 +282,7 @@ int fdt_finish(void *fdt)
 	while ((tag = fdt_next_tag(fdt, offset, &nextoffset)) != FDT_END) {
 		if (tag == FDT_PROP) {
 			struct fdt_property *prop =
-				_fdt_offset_ptr_w(fdt, offset);
+				fdt_offset_ptr_w_(fdt, offset);
 			int nameoff;
 
 			nameoff = fdt32_to_cpu(prop->nameoff);
diff --git a/core/lib/libfdt/fdt_wip.c b/core/lib/libfdt/fdt_wip.c
index c97c5f70..21550684 100644
--- a/core/lib/libfdt/fdt_wip.c
+++ b/core/lib/libfdt/fdt_wip.c
@@ -56,24 +56,45 @@
 
 #include "libfdt_internal.h"
 
+int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
+					const char *name, int namelen,
+					uint32_t idx, const void *val,
+					int len)
+{
+	void *propval;
+	int proplen;
+
+	propval = fdt_getprop_namelen_w(fdt, nodeoffset, name, namelen,
+					&proplen);
+	if (!propval)
+		return proplen;
+
+	if (proplen < (len + idx))
+		return -FDT_ERR_NOSPACE;
+
+	memcpy((char *)propval + idx, val, len);
+	return 0;
+}
+
 int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
 			const void *val, int len)
 {
-	void *propval;
+	const void *propval;
 	int proplen;
 
-	propval = fdt_getprop_w(fdt, nodeoffset, name, &proplen);
-	if (! propval)
+	propval = fdt_getprop(fdt, nodeoffset, name, &proplen);
+	if (!propval)
 		return proplen;
 
 	if (proplen != len)
 		return -FDT_ERR_NOSPACE;
 
-	memcpy(propval, val, len);
-	return 0;
+	return fdt_setprop_inplace_namelen_partial(fdt, nodeoffset, name,
+						   strlen(name), 0,
+						   val, len);
 }
 
-static void _fdt_nop_region(void *start, int len)
+static void fdt_nop_region_(void *start, int len)
 {
 	fdt32_t *p;
 
@@ -87,15 +108,15 @@ int fdt_nop_property(void *fdt, int nodeoffset, const char *name)
 	int len;
 
 	prop = fdt_get_property_w(fdt, nodeoffset, name, &len);
-	if (! prop)
+	if (!prop)
 		return len;
 
-	_fdt_nop_region(prop, len + sizeof(*prop));
+	fdt_nop_region_(prop, len + sizeof(*prop));
 
 	return 0;
 }
 
-int _fdt_node_end_offset(void *fdt, int offset)
+int fdt_node_end_offset_(void *fdt, int offset)
 {
 	int depth = 0;
 
@@ -109,11 +130,11 @@ int fdt_nop_node(void *fdt, int nodeoffset)
 {
 	int endoffset;
 
-	endoffset = _fdt_node_end_offset(fdt, nodeoffset);
+	endoffset = fdt_node_end_offset_(fdt, nodeoffset);
 	if (endoffset < 0)
 		return endoffset;
 
-	_fdt_nop_region(fdt_offset_ptr_w(fdt, nodeoffset, 0),
+	fdt_nop_region_(fdt_offset_ptr_w(fdt, nodeoffset, 0),
 			endoffset - nodeoffset);
 	return 0;
 }
diff --git a/core/lib/libfdt/include/fdt.h b/core/lib/libfdt/include/fdt.h
index 520bdcf0..99ae6eb2 100644
--- a/core/lib/libfdt/include/fdt.h
+++ b/core/lib/libfdt/include/fdt.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: (BSD-2-Clause OR GPL-2.0+) */
-#ifndef _FDT_H
-#define _FDT_H
+#ifndef FDT_H
+#define FDT_H
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
@@ -109,4 +109,4 @@ struct fdt_property {
 #define FDT_V16_SIZE	FDT_V3_SIZE
 #define FDT_V17_SIZE	(FDT_V16_SIZE + sizeof(fdt32_t))
 
-#endif /* _FDT_H */
+#endif /* FDT_H */
diff --git a/core/lib/libfdt/include/libfdt.h b/core/lib/libfdt/include/libfdt.h
index 01a9065a..672f44c7 100644
--- a/core/lib/libfdt/include/libfdt.h
+++ b/core/lib/libfdt/include/libfdt.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: (BSD-2-Clause OR GPL-2.0+) */
-#ifndef _LIBFDT_H
-#define _LIBFDT_H
+#ifndef LIBFDT_H
+#define LIBFDT_H
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
@@ -55,14 +55,14 @@
 #include <libfdt_env.h>
 #include <fdt.h>
 
-#define FDT_FIRST_SUPPORTED_VERSION	0x10
+#define FDT_FIRST_SUPPORTED_VERSION	0x02
 #define FDT_LAST_SUPPORTED_VERSION	0x11
 
 /* Error codes: informative error codes */
 #define FDT_ERR_NOTFOUND	1
 	/* FDT_ERR_NOTFOUND: The requested node or property does not exist */
 #define FDT_ERR_EXISTS		2
-	/* FDT_ERR_EXISTS: Attemped to create a node or property which
+	/* FDT_ERR_EXISTS: Attempted to create a node or property which
 	 * already exists */
 #define FDT_ERR_NOSPACE		3
 	/* FDT_ERR_NOSPACE: Operation needed to expand the device
@@ -80,8 +80,10 @@
 	 * (e.g. missing a leading / for a function which requires an
 	 * absolute path) */
 #define FDT_ERR_BADPHANDLE	6
-	/* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle
-	 * value.  phandle values of 0 and -1 are not permitted. */
+	/* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle.
+	 * This can be caused either by an invalid phandle property
+	 * length, or the phandle value was either 0 or -1, which are
+	 * not permitted. */
 #define FDT_ERR_BADSTATE	7
 	/* FDT_ERR_BADSTATE: Function was passed an incomplete device
 	 * tree created by the sequential-write functions, which is
@@ -122,13 +124,29 @@
 	/* FDT_ERR_BADNCELLS: Device tree has a #address-cells, #size-cells
 	 * or similar property with a bad format or value */
 
-#define FDT_ERR_MAX		14
+#define FDT_ERR_BADVALUE	15
+	/* FDT_ERR_BADVALUE: Device tree has a property with an unexpected
+	 * value. For example: a property expected to contain a string list
+	 * is not NUL-terminated within the length of its value. */
+
+#define FDT_ERR_BADOVERLAY	16
+	/* FDT_ERR_BADOVERLAY: The device tree overlay, while
+	 * correctly structured, cannot be applied due to some
+	 * unexpected or missing value, property or node. */
+
+#define FDT_ERR_NOPHANDLES	17
+	/* FDT_ERR_NOPHANDLES: The device tree doesn't have any
+	 * phandle available anymore without causing an overflow */
+
+#define FDT_ERR_MAX		17
 
 /**********************************************************************/
 /* Low-level functions (you probably don't need these)                */
 /**********************************************************************/
 
+#ifndef SWIG /* This function is not useful in Python */
 const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
+#endif
 static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
 {
 	return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
@@ -164,40 +182,67 @@ int fdt_first_subnode(const void *fdt, int offset);
  */
 int fdt_next_subnode(const void *fdt, int offset);
 
+/**
+ * fdt_for_each_subnode - iterate over all subnodes of a parent
+ *
+ * @node:	child node (int, lvalue)
+ * @fdt:	FDT blob (const void *)
+ * @parent:	parent node (int)
+ *
+ * This is actually a wrapper around a for loop and would be used like so:
+ *
+ *	fdt_for_each_subnode(node, fdt, parent) {
+ *		Use node
+ *		...
+ *	}
+ *
+ *	if ((node < 0) && (node != -FDT_ERR_NOT_FOUND)) {
+ *		Error handling
+ *	}
+ *
+ * Note that this is implemented as a macro and @node is used as
+ * iterator in the loop. The parent variable be constant or even a
+ * literal.
+ *
+ */
+#define fdt_for_each_subnode(node, fdt, parent)		\
+	for (node = fdt_first_subnode(fdt, parent);	\
+	     node >= 0;					\
+	     node = fdt_next_subnode(fdt, node))
+
 /**********************************************************************/
 /* General functions                                                  */
 /**********************************************************************/
-
 #define fdt_get_header(fdt, field) \
 	(fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
-#define fdt_magic(fdt) 			(fdt_get_header(fdt, magic))
+#define fdt_magic(fdt)			(fdt_get_header(fdt, magic))
 #define fdt_totalsize(fdt)		(fdt_get_header(fdt, totalsize))
 #define fdt_off_dt_struct(fdt)		(fdt_get_header(fdt, off_dt_struct))
 #define fdt_off_dt_strings(fdt)		(fdt_get_header(fdt, off_dt_strings))
 #define fdt_off_mem_rsvmap(fdt)		(fdt_get_header(fdt, off_mem_rsvmap))
 #define fdt_version(fdt)		(fdt_get_header(fdt, version))
-#define fdt_last_comp_version(fdt) 	(fdt_get_header(fdt, last_comp_version))
-#define fdt_boot_cpuid_phys(fdt) 	(fdt_get_header(fdt, boot_cpuid_phys))
-#define fdt_size_dt_strings(fdt) 	(fdt_get_header(fdt, size_dt_strings))
+#define fdt_last_comp_version(fdt)	(fdt_get_header(fdt, last_comp_version))
+#define fdt_boot_cpuid_phys(fdt)	(fdt_get_header(fdt, boot_cpuid_phys))
+#define fdt_size_dt_strings(fdt)	(fdt_get_header(fdt, size_dt_strings))
 #define fdt_size_dt_struct(fdt)		(fdt_get_header(fdt, size_dt_struct))
 
-#define __fdt_set_hdr(name) \
+#define fdt_set_hdr_(name) \
 	static inline void fdt_set_##name(void *fdt, uint32_t val) \
 	{ \
-		struct fdt_header *fdth = (struct fdt_header*)fdt; \
+		struct fdt_header *fdth = (struct fdt_header *)fdt; \
 		fdth->name = cpu_to_fdt32(val); \
 	}
-__fdt_set_hdr(magic)
-__fdt_set_hdr(totalsize)
-__fdt_set_hdr(off_dt_struct)
-__fdt_set_hdr(off_dt_strings)
-__fdt_set_hdr(off_mem_rsvmap)
-__fdt_set_hdr(version)
-__fdt_set_hdr(last_comp_version)
-__fdt_set_hdr(boot_cpuid_phys)
-__fdt_set_hdr(size_dt_strings)
-__fdt_set_hdr(size_dt_struct)
-#undef __fdt_set_hdr
+fdt_set_hdr_(magic)
+fdt_set_hdr_(totalsize)
+fdt_set_hdr_(off_dt_struct)
+fdt_set_hdr_(off_dt_strings)
+fdt_set_hdr_(off_mem_rsvmap)
+fdt_set_hdr_(version)
+fdt_set_hdr_(last_comp_version)
+fdt_set_hdr_(boot_cpuid_phys)
+fdt_set_hdr_(size_dt_strings)
+fdt_set_hdr_(size_dt_struct)
+#undef fdt_set_hdr_
 
 /**
  * fdt_check_header - sanity check a device tree or possible device tree
@@ -255,6 +300,21 @@ int fdt_move(const void *fdt, void *buf, int bufsize);
 const char *fdt_string(const void *fdt, int stroffset);
 
 /**
+ * fdt_get_max_phandle - retrieves the highest phandle in a tree
+ * @fdt: pointer to the device tree blob
+ *
+ * fdt_get_max_phandle retrieves the highest phandle in the given
+ * device tree. This will ignore badly formatted phandles, or phandles
+ * with a value of 0 or -1.
+ *
+ * returns:
+ *      the highest phandle on success
+ *      0, if no phandle was found in the device tree
+ *      -1, if an error occurred
+ */
+uint32_t fdt_get_max_phandle(const void *fdt);
+
+/**
  * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
  * @fdt: pointer to the device tree blob
  *
@@ -296,8 +356,10 @@ int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
  * useful for finding subnodes based on a portion of a larger string,
  * such as a full path.
  */
+#ifndef SWIG /* Not available in Python */
 int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
 			       const char *name, int namelen);
+#endif
 /**
  * fdt_subnode_offset - find a subnode of a given node
  * @fdt: pointer to the device tree blob
@@ -314,8 +376,9 @@ int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
  * returns:
  *	structure block offset of the requested subnode (>=0), on success
  *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
- *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
- *      -FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
+ *		tag
+ *	-FDT_ERR_BADMAGIC,
  *	-FDT_ERR_BADVERSION,
  *	-FDT_ERR_BADSTATE,
  *	-FDT_ERR_BADSTRUCTURE,
@@ -324,6 +387,19 @@ int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
 int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
 
 /**
+ * fdt_path_offset_namelen - find a tree node by its full path
+ * @fdt: pointer to the device tree blob
+ * @path: full path of the node to locate
+ * @namelen: number of characters of path to consider
+ *
+ * Identical to fdt_path_offset(), but only consider the first namelen
+ * characters of path as the path name.
+ */
+#ifndef SWIG /* Not available in Python */
+int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen);
+#endif
+
+/**
  * fdt_path_offset - find a tree node by its full path
  * @fdt: pointer to the device tree blob
  * @path: full path of the node to locate
@@ -336,7 +412,8 @@ int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
  * address).
  *
  * returns:
- *	structure block offset of the node with the requested path (>=0), on success
+ *	structure block offset of the node with the requested path (>=0), on
+ *		success
  *	-FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
  *	-FDT_ERR_NOTFOUND, if the requested node does not exist
  *      -FDT_ERR_BADMAGIC,
@@ -360,10 +437,12 @@ int fdt_path_offset(const void *fdt, const char *path);
  *
  * returns:
  *	pointer to the node's name, on success
- *		If lenp is non-NULL, *lenp contains the length of that name (>=0)
+ *		If lenp is non-NULL, *lenp contains the length of that name
+ *			(>=0)
  *	NULL, on error
  *		if lenp is non-NULL *lenp contains an error code (<0):
- *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
+ *			tag
  *		-FDT_ERR_BADMAGIC,
  *		-FDT_ERR_BADVERSION,
  *		-FDT_ERR_BADSTATE, standard meanings
@@ -412,6 +491,33 @@ int fdt_first_property_offset(const void *fdt, int nodeoffset);
 int fdt_next_property_offset(const void *fdt, int offset);
 
 /**
+ * fdt_for_each_property_offset - iterate over all properties of a node
+ *
+ * @property_offset:	property offset (int, lvalue)
+ * @fdt:		FDT blob (const void *)
+ * @node:		node offset (int)
+ *
+ * This is actually a wrapper around a for loop and would be used like so:
+ *
+ *	fdt_for_each_property_offset(property, fdt, node) {
+ *		Use property
+ *		...
+ *	}
+ *
+ *	if ((property < 0) && (property != -FDT_ERR_NOT_FOUND)) {
+ *		Error handling
+ *	}
+ *
+ * Note that this is implemented as a macro and property is used as
+ * iterator in the loop. The node variable can be constant or even a
+ * literal.
+ */
+#define fdt_for_each_property_offset(property, fdt, node)	\
+	for (property = fdt_first_property_offset(fdt, node);	\
+	     property >= 0;					\
+	     property = fdt_next_property_offset(fdt, property))
+
+/**
  * fdt_get_property_by_offset - retrieve the property at a given offset
  * @fdt: pointer to the device tree blob
  * @offset: offset of the property to retrieve
@@ -422,6 +528,9 @@ int fdt_next_property_offset(const void *fdt, int offset);
  * offset.  If lenp is non-NULL, the length of the property value is
  * also returned, in the integer pointed to by lenp.
  *
+ * Note that this code only works on device tree versions >= 16. fdt_getprop()
+ * works on all versions.
+ *
  * returns:
  *	pointer to the structure representing the property
  *		if lenp is non-NULL, *lenp contains the length of the property
@@ -447,13 +556,15 @@ const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
  * @namelen: number of characters of name to consider
  * @lenp: pointer to an integer variable (will be overwritten) or NULL
  *
- * Identical to fdt_get_property_namelen(), but only examine the first
- * namelen characters of name for matching the property name.
+ * Identical to fdt_get_property(), but only examine the first namelen
+ * characters of name for matching the property name.
  */
+#ifndef SWIG /* Not available in Python */
 const struct fdt_property *fdt_get_property_namelen(const void *fdt,
 						    int nodeoffset,
 						    const char *name,
 						    int namelen, int *lenp);
+#endif
 
 /**
  * fdt_get_property - find a given property in a given node
@@ -475,7 +586,8 @@ const struct fdt_property *fdt_get_property_namelen(const void *fdt,
  *	NULL, on error
  *		if lenp is non-NULL, *lenp contains an error code (<0):
  *		-FDT_ERR_NOTFOUND, node does not have named property
- *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
+ *			tag
  *		-FDT_ERR_BADMAGIC,
  *		-FDT_ERR_BADVERSION,
  *		-FDT_ERR_BADSTATE,
@@ -523,8 +635,10 @@ static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
  *		-FDT_ERR_BADSTRUCTURE,
  *		-FDT_ERR_TRUNCATED, standard meanings
  */
+#ifndef SWIG /* This function is not useful in Python */
 const void *fdt_getprop_by_offset(const void *fdt, int offset,
 				  const char **namep, int *lenp);
+#endif
 
 /**
  * fdt_getprop_namelen - get property value based on substring
@@ -537,8 +651,17 @@ const void *fdt_getprop_by_offset(const void *fdt, int offset,
  * Identical to fdt_getprop(), but only examine the first namelen
  * characters of name for matching the property name.
  */
+#ifndef SWIG /* Not available in Python */
 const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
 				const char *name, int namelen, int *lenp);
+static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
+					  const char *name, int namelen,
+					  int *lenp)
+{
+	return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
+						      namelen, lenp);
+}
+#endif
 
 /**
  * fdt_getprop - retrieve the value of a given property
@@ -560,7 +683,8 @@ const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
  *	NULL, on error
  *		if lenp is non-NULL, *lenp contains an error code (<0):
  *		-FDT_ERR_NOTFOUND, node does not have named property
- *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
+ *			tag
  *		-FDT_ERR_BADMAGIC,
  *		-FDT_ERR_BADVERSION,
  *		-FDT_ERR_BADSTATE,
@@ -598,11 +722,13 @@ uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
  * Identical to fdt_get_alias(), but only examine the first namelen
  * characters of name for matching the alias name.
  */
+#ifndef SWIG /* Not available in Python */
 const char *fdt_get_alias_namelen(const void *fdt,
 				  const char *name, int namelen);
+#endif
 
 /**
- * fdt_get_alias - retreive the path referenced by a given alias
+ * fdt_get_alias - retrieve the path referenced by a given alias
  * @fdt: pointer to the device tree blob
  * @name: name of the alias th look up
  *
@@ -632,7 +758,7 @@ const char *fdt_get_alias(const void *fdt, const char *name);
  *	0, on success
  *		buf contains the absolute path of the node at
  *		nodeoffset, as a NUL-terminated string.
- * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
  *	-FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
  *		characters and will not fit in the given buffer.
  *	-FDT_ERR_BADMAGIC,
@@ -662,11 +788,11 @@ int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
  * structure from the start to nodeoffset.
  *
  * returns:
-
  *	structure block offset of the node at node offset's ancestor
  *		of depth supernodedepth (>=0), on success
- * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
-*	-FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of nodeoffset
+ *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *	-FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
+ *		nodeoffset
  *	-FDT_ERR_BADMAGIC,
  *	-FDT_ERR_BADVERSION,
  *	-FDT_ERR_BADSTATE,
@@ -688,7 +814,7 @@ int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
  *
  * returns:
  *	depth of the node at nodeoffset (>=0), on success
- * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
  *	-FDT_ERR_BADMAGIC,
  *	-FDT_ERR_BADVERSION,
  *	-FDT_ERR_BADSTATE,
@@ -711,7 +837,7 @@ int fdt_node_depth(const void *fdt, int nodeoffset);
  * returns:
  *	structure block offset of the parent of the node at nodeoffset
  *		(>=0), on success
- * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
  *	-FDT_ERR_BADMAGIC,
  *	-FDT_ERR_BADVERSION,
  *	-FDT_ERR_BADSTATE,
@@ -751,7 +877,7 @@ int fdt_parent_offset(const void *fdt, int nodeoffset);
  *		 on success
  *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
  *		tree after startoffset
- * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
  *	-FDT_ERR_BADMAGIC,
  *	-FDT_ERR_BADVERSION,
  *	-FDT_ERR_BADSTATE,
@@ -798,7 +924,7 @@ int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
  *	1, if the node has a 'compatible' property, but it does not list
  *		the given string
  *	-FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
- * 	-FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
+ *	-FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
  *	-FDT_ERR_BADMAGIC,
  *	-FDT_ERR_BADVERSION,
  *	-FDT_ERR_BADSTATE,
@@ -835,7 +961,7 @@ int fdt_node_check_compatible(const void *fdt, int nodeoffset,
  *		 on success
  *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
  *		tree after startoffset
- * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
  *	-FDT_ERR_BADMAGIC,
  *	-FDT_ERR_BADVERSION,
  *	-FDT_ERR_BADSTATE,
@@ -858,6 +984,68 @@ int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
  */
 int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
 
+/**
+ * fdt_stringlist_count - count the number of strings in a string list
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of a tree node
+ * @property: name of the property containing the string list
+ * @return:
+ *   the number of strings in the given property
+ *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
+ *   -FDT_ERR_NOTFOUND if the property does not exist
+ */
+int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property);
+
+/**
+ * fdt_stringlist_search - find a string in a string list and return its index
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of a tree node
+ * @property: name of the property containing the string list
+ * @string: string to look up in the string list
+ *
+ * Note that it is possible for this function to succeed on property values
+ * that are not NUL-terminated. That's because the function will stop after
+ * finding the first occurrence of @string. This can for example happen with
+ * small-valued cell properties, such as #address-cells, when searching for
+ * the empty string.
+ *
+ * @return:
+ *   the index of the string in the list of strings
+ *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
+ *   -FDT_ERR_NOTFOUND if the property does not exist or does not contain
+ *                     the given string
+ */
+int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
+			  const char *string);
+
+/**
+ * fdt_stringlist_get() - obtain the string at a given index in a string list
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of a tree node
+ * @property: name of the property containing the string list
+ * @index: index of the string to return
+ * @lenp: return location for the string length or an error code on failure
+ *
+ * Note that this will successfully extract strings from properties with
+ * non-NUL-terminated values. For example on small-valued cell properties
+ * this function will return the empty string.
+ *
+ * If non-NULL, the length of the string (on success) or a negative error-code
+ * (on failure) will be stored in the integer pointer to by lenp.
+ *
+ * @return:
+ *   A pointer to the string at the given index in the string list or NULL on
+ *   failure. On success the length of the string will be stored in the memory
+ *   location pointed to by the lenp parameter, if non-NULL. On failure one of
+ *   the following negative error codes will be returned in the lenp parameter
+ *   (if non-NULL):
+ *     -FDT_ERR_BADVALUE if the property value is not NUL-terminated
+ *     -FDT_ERR_NOTFOUND if the property does not exist
+ */
+const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
+			       const char *property, int index,
+			       int *lenp);
+
 /**********************************************************************/
 /* Read-only functions (addressing related)                           */
 /**********************************************************************/
@@ -883,7 +1071,8 @@ int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
  * returns:
  *	0 <= n < FDT_MAX_NCELLS, on success
  *      2, if the node has no #address-cells property
- *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid #address-cells property
+ *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
+ *		#address-cells property
  *	-FDT_ERR_BADMAGIC,
  *	-FDT_ERR_BADVERSION,
  *	-FDT_ERR_BADSTATE,
@@ -903,7 +1092,8 @@ int fdt_address_cells(const void *fdt, int nodeoffset);
  * returns:
  *	0 <= n < FDT_MAX_NCELLS, on success
  *      2, if the node has no #address-cells property
- *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid #size-cells property
+ *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
+ *		#size-cells property
  *	-FDT_ERR_BADMAGIC,
  *	-FDT_ERR_BADVERSION,
  *	-FDT_ERR_BADSTATE,
@@ -918,6 +1108,29 @@ int fdt_size_cells(const void *fdt, int nodeoffset);
 /**********************************************************************/
 
 /**
+ * fdt_setprop_inplace_namelen_partial - change a property's value,
+ *                                       but not its size
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @namelen: number of characters of name to consider
+ * @idx: index of the property to change in the array
+ * @val: pointer to data to replace the property value with
+ * @len: length of the property value
+ *
+ * Identical to fdt_setprop_inplace(), but modifies the given property
+ * starting from the given index, and using only the first characters
+ * of the name. It is useful when you want to manipulate only one value of
+ * an array and you have a string that doesn't end with \0.
+ */
+#ifndef SWIG /* Not available in Python */
+int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
+					const char *name, int namelen,
+					uint32_t idx, const void *val,
+					int len);
+#endif
+
+/**
  * fdt_setprop_inplace - change a property's value, but not its size
  * @fdt: pointer to the device tree blob
  * @nodeoffset: offset of the node whose property to change
@@ -945,8 +1158,10 @@ int fdt_size_cells(const void *fdt, int nodeoffset);
  *	-FDT_ERR_BADSTRUCTURE,
  *	-FDT_ERR_TRUNCATED, standard meanings
  */
+#ifndef SWIG /* Not available in Python */
 int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
 			const void *val, int len);
+#endif
 
 /**
  * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
@@ -1103,6 +1318,22 @@ static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
 {
 	return fdt_property_u32(fdt, name, val);
 }
+
+/**
+ * fdt_property_placeholder - add a new property and return a ptr to its value
+ *
+ * @fdt: pointer to the device tree blob
+ * @name: name of property to add
+ * @len: length of property value in bytes
+ * @valp: returns a pointer to where where the value should be placed
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_NOSPACE, standard meanings
+ */
+int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp);
+
 #define fdt_property_string(fdt, name, str) \
 	fdt_property(fdt, name, str, strlen(str)+1)
 int fdt_end_node(void *fdt);
@@ -1222,6 +1453,37 @@ int fdt_setprop(void *fdt, int nodeoffset, const char *name,
 		const void *val, int len);
 
 /**
+ * fdt_setprop_placeholder - allocate space for a property
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @len: length of the property value
+ * @prop_data: return pointer to property data
+ *
+ * fdt_setprop_placeholer() allocates the named property in the given node.
+ * If the property exists it is resized. In either case a pointer to the
+ * property data is returned.
+ *
+ * This function may insert or delete data from the blob, and will
+ * therefore change the offsets of some existing nodes.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
+ *		contain the new property value
+ *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
+			    int len, void **prop_data);
+
+/**
  * fdt_setprop_u32 - set a property to a 32-bit integer
  * @fdt: pointer to the device tree blob
  * @nodeoffset: offset of the node whose property to change
@@ -1333,6 +1595,36 @@ static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
 #define fdt_setprop_string(fdt, nodeoffset, name, str) \
 	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
 
+
+/**
+ * fdt_setprop_empty - set a property to an empty value
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ *
+ * fdt_setprop_empty() sets the value of the named property in the
+ * given node to an empty (zero length) value, or creates a new empty
+ * property if it does not already exist.
+ *
+ * This function may insert or delete data from the blob, and will
+ * therefore change the offsets of some existing nodes.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
+ *		contain the new property value
+ *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
+#define fdt_setprop_empty(fdt, nodeoffset, name) \
+	fdt_setprop((fdt), (nodeoffset), (name), NULL, 0)
+
 /**
  * fdt_appendprop - append to or create a property
  * @fdt: pointer to the device tree blob
@@ -1510,8 +1802,10 @@ int fdt_delprop(void *fdt, int nodeoffset, const char *name);
  * creating subnodes based on a portion of a larger string, such as a
  * full path.
  */
+#ifndef SWIG /* Not available in Python */
 int fdt_add_subnode_namelen(void *fdt, int parentoffset,
 			    const char *name, int namelen);
+#endif
 
 /**
  * fdt_add_subnode - creates a new node
@@ -1527,9 +1821,11 @@ int fdt_add_subnode_namelen(void *fdt, int parentoffset,
  * change the offsets of some existing nodes.
 
  * returns:
- *	structure block offset of the created nodeequested subnode (>=0), on success
+ *	structure block offset of the created nodeequested subnode (>=0), on
+ *		success
  *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
- *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
+ *		tag
  *	-FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
  *		the given name
  *	-FDT_ERR_NOSPACE, if there is insufficient free space in the
@@ -1567,10 +1863,41 @@ int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
  */
 int fdt_del_node(void *fdt, int nodeoffset);
 
+/**
+ * fdt_overlay_apply - Applies a DT overlay on a base DT
+ * @fdt: pointer to the base device tree blob
+ * @fdto: pointer to the device tree overlay blob
+ *
+ * fdt_overlay_apply() will apply the given device tree overlay on the
+ * given base device tree.
+ *
+ * Expect the base device tree to be modified, even if the function
+ * returns an error.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOSPACE, there's not enough space in the base device tree
+ *	-FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
+ *		properties in the base DT
+ *	-FDT_ERR_BADPHANDLE,
+ *	-FDT_ERR_BADOVERLAY,
+ *	-FDT_ERR_NOPHANDLES,
+ *	-FDT_ERR_INTERNAL,
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADOFFSET,
+ *	-FDT_ERR_BADPATH,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_overlay_apply(void *fdt, void *fdto);
+
 /**********************************************************************/
 /* Debugging / informational functions                                */
 /**********************************************************************/
 
 const char *fdt_strerror(int errval);
 
-#endif /* _LIBFDT_H */
+#endif /* LIBFDT_H */
diff --git a/core/lib/libfdt/include/libfdt_env.h b/core/lib/libfdt/include/libfdt_env.h
index b0e44457..3b108522 100644
--- a/core/lib/libfdt/include/libfdt_env.h
+++ b/core/lib/libfdt/include/libfdt_env.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: (BSD-2-Clause OR GPL-2.0+) */
-#ifndef _LIBFDT_ENV_H
-#define _LIBFDT_ENV_H
+#ifndef LIBFDT_ENV_H
+#define LIBFDT_ENV_H
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
@@ -55,19 +55,20 @@
 
 #include <stddef.h>
 #include <stdint.h>
+#include <stdlib.h>
 #include <string.h>
 
 #ifdef __CHECKER__
-#define __force __attribute__((force))
-#define __bitwise __attribute__((bitwise))
+#define FDT_FORCE __attribute__((force))
+#define FDT_BITWISE __attribute__((bitwise))
 #else
-#define __force
-#define __bitwise
+#define FDT_FORCE
+#define FDT_BITWISE
 #endif
 
-typedef uint16_t __bitwise fdt16_t;
-typedef uint32_t __bitwise fdt32_t;
-typedef uint64_t __bitwise fdt64_t;
+typedef uint16_t FDT_BITWISE fdt16_t;
+typedef uint32_t FDT_BITWISE fdt32_t;
+typedef uint64_t FDT_BITWISE fdt64_t;
 
 #define EXTRACT_BYTE(x, n)	((unsigned long long)((uint8_t *)&x)[n])
 #define CPU_TO_FDT16(x) ((EXTRACT_BYTE(x, 0) << 8) | EXTRACT_BYTE(x, 1))
@@ -80,33 +81,60 @@ typedef uint64_t __bitwise fdt64_t;
 
 static inline uint16_t fdt16_to_cpu(fdt16_t x)
 {
-	return (__force uint16_t)CPU_TO_FDT16(x);
+	return (FDT_FORCE uint16_t)CPU_TO_FDT16(x);
 }
 static inline fdt16_t cpu_to_fdt16(uint16_t x)
 {
-	return (__force fdt16_t)CPU_TO_FDT16(x);
+	return (FDT_FORCE fdt16_t)CPU_TO_FDT16(x);
 }
 
 static inline uint32_t fdt32_to_cpu(fdt32_t x)
 {
-	return (__force uint32_t)CPU_TO_FDT32(x);
+	return (FDT_FORCE uint32_t)CPU_TO_FDT32(x);
 }
 static inline fdt32_t cpu_to_fdt32(uint32_t x)
 {
-	return (__force fdt32_t)CPU_TO_FDT32(x);
+	return (FDT_FORCE fdt32_t)CPU_TO_FDT32(x);
 }
 
 static inline uint64_t fdt64_to_cpu(fdt64_t x)
 {
-	return (__force uint64_t)CPU_TO_FDT64(x);
+	return (FDT_FORCE uint64_t)CPU_TO_FDT64(x);
 }
 static inline fdt64_t cpu_to_fdt64(uint64_t x)
 {
-	return (__force fdt64_t)CPU_TO_FDT64(x);
+	return (FDT_FORCE fdt64_t)CPU_TO_FDT64(x);
 }
 #undef CPU_TO_FDT64
 #undef CPU_TO_FDT32
 #undef CPU_TO_FDT16
 #undef EXTRACT_BYTE
 
-#endif /* _LIBFDT_ENV_H */
+#ifdef __APPLE__
+#include <AvailabilityMacros.h>
+
+/* strnlen() is not available on Mac OS < 10.7 */
+# if !defined(MAC_OS_X_VERSION_10_7) || (MAC_OS_X_VERSION_MAX_ALLOWED < \
+                                         MAC_OS_X_VERSION_10_7)
+
+#define strnlen fdt_strnlen
+
+/*
+ * fdt_strnlen: returns the length of a string or max_count - which ever is
+ * smallest.
+ * Input 1 string: the string whose size is to be determined
+ * Input 2 max_count: the maximum value returned by this function
+ * Output: length of the string or max_count (the smallest of the two)
+ */
+static inline size_t fdt_strnlen(const char *string, size_t max_count)
+{
+    const char *p = memchr(string, 0, max_count);
+    return p ? p - string : max_count;
+}
+
+#endif /* !defined(MAC_OS_X_VERSION_10_7) || (MAC_OS_X_VERSION_MAX_ALLOWED <
+          MAC_OS_X_VERSION_10_7) */
+
+#endif /* __APPLE__ */
+
+#endif /* LIBFDT_ENV_H */
diff --git a/core/lib/libfdt/libfdt_internal.h b/core/lib/libfdt/libfdt_internal.h
index bd16520d..9410e3df 100644
--- a/core/lib/libfdt/libfdt_internal.h
+++ b/core/lib/libfdt/libfdt_internal.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: (BSD-2-Clause OR GPL-2.0+) */
-#ifndef _LIBFDT_INTERNAL_H
-#define _LIBFDT_INTERNAL_H
+#ifndef LIBFDT_INTERNAL_H
+#define LIBFDT_INTERNAL_H
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
@@ -58,27 +58,27 @@
 
 #define FDT_CHECK_HEADER(fdt) \
 	{ \
-		int __err; \
-		if ((__err = fdt_check_header(fdt)) != 0) \
-			return __err; \
+		int err_; \
+		if ((err_ = fdt_check_header(fdt)) != 0) \
+			return err_; \
 	}
 
-int _fdt_check_node_offset(const void *fdt, int offset);
-int _fdt_check_prop_offset(const void *fdt, int offset);
-const char *_fdt_find_string(const char *strtab, int tabsize, const char *s);
-int _fdt_node_end_offset(void *fdt, int nodeoffset);
+int fdt_check_node_offset_(const void *fdt, int offset);
+int fdt_check_prop_offset_(const void *fdt, int offset);
+const char *fdt_find_string_(const char *strtab, int tabsize, const char *s);
+int fdt_node_end_offset_(void *fdt, int nodeoffset);
 
-static inline const void *_fdt_offset_ptr(const void *fdt, int offset)
+static inline const void *fdt_offset_ptr_(const void *fdt, int offset)
 {
 	return (const char *)fdt + fdt_off_dt_struct(fdt) + offset;
 }
 
-static inline void *_fdt_offset_ptr_w(void *fdt, int offset)
+static inline void *fdt_offset_ptr_w_(void *fdt, int offset)
 {
-	return (void *)(uintptr_t)_fdt_offset_ptr(fdt, offset);
+	return (void *)(uintptr_t)fdt_offset_ptr_(fdt, offset);
 }
 
-static inline const struct fdt_reserve_entry *_fdt_mem_rsv(const void *fdt, int n)
+static inline const struct fdt_reserve_entry *fdt_mem_rsv_(const void *fdt, int n)
 {
 	const struct fdt_reserve_entry *rsv_table =
 		(const struct fdt_reserve_entry *)
@@ -86,11 +86,11 @@ static inline const struct fdt_reserve_entry *_fdt_mem_rsv(const void *fdt, int
 
 	return rsv_table + n;
 }
-static inline struct fdt_reserve_entry *_fdt_mem_rsv_w(void *fdt, int n)
+static inline struct fdt_reserve_entry *fdt_mem_rsv_w_(void *fdt, int n)
 {
-	return (void *)(uintptr_t)_fdt_mem_rsv(fdt, n);
+	return (void *)(uintptr_t)fdt_mem_rsv_(fdt, n);
 }
 
 #define FDT_SW_MAGIC		(~FDT_MAGIC)
 
-#endif /* _LIBFDT_INTERNAL_H */
+#endif /* LIBFDT_INTERNAL_H */
diff --git a/core/lib/libfdt/sub.mk b/core/lib/libfdt/sub.mk
index b136ed08..3ea4b358 100644
--- a/core/lib/libfdt/sub.mk
+++ b/core/lib/libfdt/sub.mk
@@ -3,4 +3,4 @@ cflags-y += -Wno-cast-align
 cflags-y += -Wno-sign-compare
 cflags-y += -Wno-switch-default
 srcs-y += fdt.c fdt_ro.c fdt_wip.c fdt_sw.c fdt_rw.c fdt_strerror.c
-srcs-y += fdt_empty_tree.c fdt_addresses.c
+srcs-y += fdt_empty_tree.c fdt_addresses.c fdt_overlay.c