diff --git a/scripts/dtc/Makefile b/scripts/dtc/Makefile
index 1c943e0..8216080 100644
--- a/scripts/dtc/Makefile
+++ b/scripts/dtc/Makefile
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 # scripts/dtc makefile
 
-hostprogs-y	:= dtc
+hostprogs-$(CONFIG_DTC) := dtc
 always		:= $(hostprogs-y)
 
 dtc-objs	:= dtc.o flattree.o fstree.o data.o livetree.o treesource.o \
@@ -9,11 +9,22 @@
 dtc-objs	+= dtc-lexer.lex.o dtc-parser.tab.o
 
 # Source files need to get at the userspace version of libfdt_env.h to compile
-HOST_EXTRACFLAGS := -I$(src)/libfdt
+HOST_EXTRACFLAGS := -I $(srctree)/$(src)/libfdt
+
+ifeq ($(wildcard /usr/include/yaml.h),)
+ifneq ($(CHECK_DTBS),)
+$(error dtc needs libyaml for DT schema validation support. \
+	Install the necessary libyaml development package.)
+endif
+HOST_EXTRACFLAGS += -DNO_YAML
+else
+dtc-objs	+= yamltree.o
+HOSTLDLIBS_dtc	:= -lyaml
+endif
 
 # Generated files need one more search path to include headers in source tree
-HOSTCFLAGS_dtc-lexer.lex.o := -I$(src)
-HOSTCFLAGS_dtc-parser.tab.o := -I$(src)
+HOSTCFLAGS_dtc-lexer.lex.o := -I $(srctree)/$(src)
+HOSTCFLAGS_dtc-parser.tab.o := -I $(srctree)/$(src)
 
 # dependencies on generated files need to be listed explicitly
 $(obj)/dtc-lexer.lex.o: $(obj)/dtc-parser.tab.h
diff --git a/scripts/dtc/Makefile.dtc b/scripts/dtc/Makefile.dtc
index bece49b..9c467b0 100644
--- a/scripts/dtc/Makefile.dtc
+++ b/scripts/dtc/Makefile.dtc
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
 # Makefile.dtc
 #
 # This is not a complete Makefile of itself.  Instead, it is designed to
@@ -14,5 +15,9 @@
 	treesource.c \
 	util.c
 
+ifneq ($(NO_YAML),1)
+DTC_SRCS += yamltree.c
+endif
+
 DTC_GEN_SRCS = dtc-lexer.lex.c dtc-parser.tab.c
 DTC_OBJS = $(DTC_SRCS:%.c=%.o) $(DTC_GEN_SRCS:%.c=%.o)
diff --git a/scripts/dtc/checks.c b/scripts/dtc/checks.c
index a2cc103..d7986ee 100644
--- a/scripts/dtc/checks.c
+++ b/scripts/dtc/checks.c
@@ -1,24 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2007.
- *
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 
 #include "dtc.h"
+#include "srcpos.h"
 
 #ifdef TRACE_CHECKS
 #define TRACE(c, ...) \
@@ -78,23 +64,56 @@
 					   const char *fmt, ...)
 {
 	va_list ap;
-	va_start(ap, fmt);
+	char *str = NULL;
+	struct srcpos *pos = NULL;
+	char *file_str;
 
-	if ((c->warn && (quiet < 1))
-	    || (c->error && (quiet < 2))) {
-		fprintf(stderr, "%s: %s (%s): ",
-			strcmp(dti->outname, "-") ? dti->outname : "<stdout>",
-			(c->error) ? "ERROR" : "Warning", c->name);
-		if (node) {
-			fprintf(stderr, "%s", node->fullpath);
-			if (prop)
-				fprintf(stderr, ":%s", prop->name);
-			fputs(": ", stderr);
-		}
-		vfprintf(stderr, fmt, ap);
-		fprintf(stderr, "\n");
+	if (!(c->warn && (quiet < 1)) && !(c->error && (quiet < 2)))
+		return;
+
+	if (prop && prop->srcpos)
+		pos = prop->srcpos;
+	else if (node && node->srcpos)
+		pos = node->srcpos;
+
+	if (pos) {
+		file_str = srcpos_string(pos);
+		xasprintf(&str, "%s", file_str);
+		free(file_str);
+	} else if (streq(dti->outname, "-")) {
+		xasprintf(&str, "<stdout>");
+	} else {
+		xasprintf(&str, "%s", dti->outname);
 	}
+
+	xasprintf_append(&str, ": %s (%s): ",
+			(c->error) ? "ERROR" : "Warning", c->name);
+
+	if (node) {
+		if (prop)
+			xasprintf_append(&str, "%s:%s: ", node->fullpath, prop->name);
+		else
+			xasprintf_append(&str, "%s: ", node->fullpath);
+	}
+
+	va_start(ap, fmt);
+	xavsprintf_append(&str, fmt, ap);
 	va_end(ap);
+
+	xasprintf_append(&str, "\n");
+
+	if (!prop && pos) {
+		pos = node->srcpos;
+		while (pos->next) {
+			pos = pos->next;
+
+			file_str = srcpos_string(pos);
+			xasprintf_append(&str, "  also defined at %s\n", file_str);
+			free(file_str);
+		}
+	}
+
+	fputs(str, stderr);
 }
 
 #define FAIL(c, dti, node, ...)						\
@@ -626,6 +645,8 @@
 static void fixup_omit_unused_nodes(struct check *c, struct dt_info *dti,
 				    struct node *node)
 {
+	if (generate_symbols && node->labels)
+		return;
 	if (node->omit_if_unused && !node->is_referenced)
 		delete_node(node);
 }
@@ -910,7 +931,7 @@
 
 	for (str = prop->val.val, end = str + prop->val.len; str < end;
 	     str += strnlen(str, end - str) + 1) {
-		if (strprefixeq(str, end - str, compat))
+		if (streq(str, compat))
 			return true;
 	}
 	return false;
@@ -921,7 +942,8 @@
 	if (node_is_compatible(node, "simple-bus"))
 		node->bus = &simple_bus;
 }
-WARNING(simple_bus_bridge, check_simple_bus_bridge, NULL, &addr_size_cells);
+WARNING(simple_bus_bridge, check_simple_bus_bridge, NULL,
+	&addr_size_cells, &compatible_is_string_list);
 
 static void check_simple_bus_reg(struct check *c, struct dt_info *dti, struct node *node)
 {
@@ -962,6 +984,149 @@
 }
 WARNING(simple_bus_reg, check_simple_bus_reg, NULL, &reg_format, &simple_bus_bridge);
 
+static const struct bus_type i2c_bus = {
+	.name = "i2c-bus",
+};
+
+static void check_i2c_bus_bridge(struct check *c, struct dt_info *dti, struct node *node)
+{
+	if (strprefixeq(node->name, node->basenamelen, "i2c-bus") ||
+	    strprefixeq(node->name, node->basenamelen, "i2c-arb")) {
+		node->bus = &i2c_bus;
+	} else if (strprefixeq(node->name, node->basenamelen, "i2c")) {
+		struct node *child;
+		for_each_child(node, child) {
+			if (strprefixeq(child->name, node->basenamelen, "i2c-bus"))
+				return;
+		}
+		node->bus = &i2c_bus;
+	} else
+		return;
+
+	if (!node->children)
+		return;
+
+	if (node_addr_cells(node) != 1)
+		FAIL(c, dti, node, "incorrect #address-cells for I2C bus");
+	if (node_size_cells(node) != 0)
+		FAIL(c, dti, node, "incorrect #size-cells for I2C bus");
+
+}
+WARNING(i2c_bus_bridge, check_i2c_bus_bridge, NULL, &addr_size_cells);
+
+static void check_i2c_bus_reg(struct check *c, struct dt_info *dti, struct node *node)
+{
+	struct property *prop;
+	const char *unitname = get_unitname(node);
+	char unit_addr[17];
+	uint32_t reg = 0;
+	int len;
+	cell_t *cells = NULL;
+
+	if (!node->parent || (node->parent->bus != &i2c_bus))
+		return;
+
+	prop = get_property(node, "reg");
+	if (prop)
+		cells = (cell_t *)prop->val.val;
+
+	if (!cells) {
+		FAIL(c, dti, node, "missing or empty reg property");
+		return;
+	}
+
+	reg = fdt32_to_cpu(*cells);
+	snprintf(unit_addr, sizeof(unit_addr), "%x", reg);
+	if (!streq(unitname, unit_addr))
+		FAIL(c, dti, node, "I2C bus unit address format error, expected \"%s\"",
+		     unit_addr);
+
+	for (len = prop->val.len; len > 0; len -= 4) {
+		reg = fdt32_to_cpu(*(cells++));
+		if (reg > 0x3ff)
+			FAIL_PROP(c, dti, node, prop, "I2C address must be less than 10-bits, got \"0x%x\"",
+				  reg);
+
+	}
+}
+WARNING(i2c_bus_reg, check_i2c_bus_reg, NULL, &reg_format, &i2c_bus_bridge);
+
+static const struct bus_type spi_bus = {
+	.name = "spi-bus",
+};
+
+static void check_spi_bus_bridge(struct check *c, struct dt_info *dti, struct node *node)
+{
+	int spi_addr_cells = 1;
+
+	if (strprefixeq(node->name, node->basenamelen, "spi")) {
+		node->bus = &spi_bus;
+	} else {
+		/* Try to detect SPI buses which don't have proper node name */
+		struct node *child;
+
+		if (node_addr_cells(node) != 1 || node_size_cells(node) != 0)
+			return;
+
+		for_each_child(node, child) {
+			struct property *prop;
+			for_each_property(child, prop) {
+				if (strprefixeq(prop->name, 4, "spi-")) {
+					node->bus = &spi_bus;
+					break;
+				}
+			}
+			if (node->bus == &spi_bus)
+				break;
+		}
+
+		if (node->bus == &spi_bus && get_property(node, "reg"))
+			FAIL(c, dti, node, "node name for SPI buses should be 'spi'");
+	}
+	if (node->bus != &spi_bus || !node->children)
+		return;
+
+	if (get_property(node, "spi-slave"))
+		spi_addr_cells = 0;
+	if (node_addr_cells(node) != spi_addr_cells)
+		FAIL(c, dti, node, "incorrect #address-cells for SPI bus");
+	if (node_size_cells(node) != 0)
+		FAIL(c, dti, node, "incorrect #size-cells for SPI bus");
+
+}
+WARNING(spi_bus_bridge, check_spi_bus_bridge, NULL, &addr_size_cells);
+
+static void check_spi_bus_reg(struct check *c, struct dt_info *dti, struct node *node)
+{
+	struct property *prop;
+	const char *unitname = get_unitname(node);
+	char unit_addr[9];
+	uint32_t reg = 0;
+	cell_t *cells = NULL;
+
+	if (!node->parent || (node->parent->bus != &spi_bus))
+		return;
+
+	if (get_property(node->parent, "spi-slave"))
+		return;
+
+	prop = get_property(node, "reg");
+	if (prop)
+		cells = (cell_t *)prop->val.val;
+
+	if (!cells) {
+		FAIL(c, dti, node, "missing or empty reg property");
+		return;
+	}
+
+	reg = fdt32_to_cpu(*cells);
+	snprintf(unit_addr, sizeof(unit_addr), "%x", reg);
+	if (!streq(unitname, unit_addr))
+		FAIL(c, dti, node, "SPI bus unit address format error, expected \"%s\"",
+		     unit_addr);
+}
+WARNING(spi_bus_reg, check_spi_bus_reg, NULL, &reg_format, &spi_bus_bridge);
+
 static void check_unit_address_format(struct check *c, struct dt_info *dti,
 				      struct node *node)
 {
@@ -1034,8 +1199,24 @@
 }
 WARNING(avoid_unnecessary_addr_size, check_avoid_unnecessary_addr_size, NULL, &avoid_default_addr_size);
 
-static void check_unique_unit_address(struct check *c, struct dt_info *dti,
-					      struct node *node)
+static bool node_is_disabled(struct node *node)
+{
+	struct property *prop;
+
+	prop = get_property(node, "status");
+	if (prop) {
+		char *str = prop->val.val;
+		if (streq("disabled", str))
+			return true;
+	}
+
+	return false;
+}
+
+static void check_unique_unit_address_common(struct check *c,
+						struct dt_info *dti,
+						struct node *node,
+						bool disable_check)
 {
 	struct node *childa;
 
@@ -1052,18 +1233,38 @@
 		if (!strlen(addr_a))
 			continue;
 
+		if (disable_check && node_is_disabled(childa))
+			continue;
+
 		for_each_child(node, childb) {
 			const char *addr_b = get_unitname(childb);
 			if (childa == childb)
 				break;
 
+			if (disable_check && node_is_disabled(childb))
+				continue;
+
 			if (streq(addr_a, addr_b))
 				FAIL(c, dti, childb, "duplicate unit-address (also used in node %s)", childa->fullpath);
 		}
 	}
 }
+
+static void check_unique_unit_address(struct check *c, struct dt_info *dti,
+					      struct node *node)
+{
+	check_unique_unit_address_common(c, dti, node, false);
+}
 WARNING(unique_unit_address, check_unique_unit_address, NULL, &avoid_default_addr_size);
 
+static void check_unique_unit_address_if_enabled(struct check *c, struct dt_info *dti,
+					      struct node *node)
+{
+	check_unique_unit_address_common(c, dti, node, true);
+}
+CHECK_ENTRY(unique_unit_address_if_enabled, check_unique_unit_address_if_enabled,
+	    NULL, false, false, &avoid_default_addr_size);
+
 static void check_obsolete_chosen_interrupt_controller(struct check *c,
 						       struct dt_info *dti,
 						       struct node *node)
@@ -1364,10 +1565,14 @@
 		prop = get_property(parent, "interrupt-parent");
 		if (prop) {
 			phandle = propval_cell(prop);
-			/* Give up if this is an overlay with external references */
-			if ((phandle == 0 || phandle == -1) &&
-			    (dti->dtsflags & DTSF_PLUGIN))
+			if ((phandle == 0) || (phandle == -1)) {
+				/* Give up if this is an overlay with
+				 * external references */
+				if (dti->dtsflags & DTSF_PLUGIN)
 					return;
+				FAIL_PROP(c, dti, parent, prop, "Invalid phandle");
+				continue;
+			}
 
 			irq_node = get_node_by_phandle(root, phandle);
 			if (!irq_node) {
@@ -1536,7 +1741,7 @@
 		return;
 
 	if (!strprefixeq(node->name, node->basenamelen, "endpoint"))
-		FAIL(c, dti, node, "graph endpont node name should be 'endpoint'");
+		FAIL(c, dti, node, "graph endpoint node name should be 'endpoint'");
 
 	check_graph_reg(c, dti, node);
 
@@ -1582,9 +1787,16 @@
 	&simple_bus_bridge,
 	&simple_bus_reg,
 
+	&i2c_bus_bridge,
+	&i2c_bus_reg,
+
+	&spi_bus_bridge,
+	&spi_bus_reg,
+
 	&avoid_default_addr_size,
 	&avoid_unnecessary_addr_size,
 	&unique_unit_address,
+	&unique_unit_address_if_enabled,
 	&obsolete_chosen_interrupt_controller,
 	&chosen_node_is_root, &chosen_node_bootargs, &chosen_node_stdout_path,
 
diff --git a/scripts/dtc/data.c b/scripts/dtc/data.c
index aa37a16..0a43b6d 100644
--- a/scripts/dtc/data.c
+++ b/scripts/dtc/data.c
@@ -1,21 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
- *
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 
 #include "dtc.h"
@@ -74,7 +59,8 @@
 	struct data d;
 	char *q;
 
-	d = data_grow_for(empty_data, len + 1);
+	d = data_add_marker(empty_data, TYPE_STRING, NULL);
+	d = data_grow_for(d, len + 1);
 
 	q = d.val;
 	while (i < len) {
@@ -94,6 +80,7 @@
 {
 	struct data d = empty_data;
 
+	d = data_add_marker(d, TYPE_NONE, NULL);
 	while (!feof(f) && (d.len < maxlen)) {
 		size_t chunksize, ret;
 
diff --git a/scripts/dtc/dt_to_config b/scripts/dtc/dt_to_config
index 5dfd1bf..299d1c2 100755
--- a/scripts/dtc/dt_to_config
+++ b/scripts/dtc/dt_to_config
@@ -1,10 +1,9 @@
 #!/usr/bin/env perl
+# SPDX-License-Identifier: GPL-2.0-only
 
 # Copyright 2016 by Frank Rowand
 # Copyright 2016 by Gaurav Minocha
 #
-# This file is subject to the terms and conditions of the GNU General Public
-# License v2.
 
 use strict 'refs';
 use strict subs;
diff --git a/scripts/dtc/dtc-lexer.l b/scripts/dtc/dtc-lexer.l
index 615b7ec..5c6c3fd 100644
--- a/scripts/dtc/dtc-lexer.l
+++ b/scripts/dtc/dtc-lexer.l
@@ -1,21 +1,6 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 /*
  * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
- *
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 
 %option noyywrap nounput noinput never-interactive
@@ -213,14 +198,14 @@
 <*>\&{LABEL}	{	/* label reference */
 			DPRINT("Ref: %s\n", yytext+1);
 			yylval.labelref = xstrdup(yytext+1);
-			return DT_REF;
+			return DT_LABEL_REF;
 		}
 
 <*>"&{/"{PATHCHAR}*\}	{	/* new-style path reference */
 			yytext[yyleng-1] = '\0';
 			DPRINT("Ref: %s\n", yytext+2);
 			yylval.labelref = xstrdup(yytext+2);
-			return DT_REF;
+			return DT_PATH_REF;
 		}
 
 <BYTESTRING>[0-9a-fA-F]{2} {
diff --git a/scripts/dtc/dtc-parser.y b/scripts/dtc/dtc-parser.y
index 011a5b2..2ed4dc1 100644
--- a/scripts/dtc/dtc-parser.y
+++ b/scripts/dtc/dtc-parser.y
@@ -1,21 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
- *
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 %{
 #include <stdio.h>
@@ -70,7 +55,8 @@
 %token <byte> DT_BYTE
 %token <data> DT_STRING
 %token <labelref> DT_LABEL
-%token <labelref> DT_REF
+%token <labelref> DT_LABEL_REF
+%token <labelref> DT_PATH_REF
 %token DT_INCBIN
 
 %type <data> propdata
@@ -83,6 +69,7 @@
 %type <data> bytestring
 %type <prop> propdef
 %type <proplist> proplist
+%type <labelref> dt_ref
 
 %type <node> devicetree
 %type <node> nodedef
@@ -158,6 +145,8 @@
 		}
 	;
 
+dt_ref: DT_LABEL_REF | DT_PATH_REF;
+
 devicetree:
 	  '/' nodedef
 		{
@@ -167,7 +156,7 @@
 		{
 			$$ = merge_nodes($1, $3);
 		}
-	| DT_REF nodedef
+	| dt_ref nodedef
 		{
 			/*
 			 * We rely on the rule being always:
@@ -176,9 +165,12 @@
 			 */
 			if (!($<flags>-1 & DTSF_PLUGIN))
 				ERROR(&@2, "Label or path %s not found", $1);
-			$$ = add_orphan_node(name_node(build_node(NULL, NULL), ""), $2, $1);
+			$$ = add_orphan_node(
+					name_node(build_node(NULL, NULL, NULL),
+						  ""),
+					$2, $1);
 		}
-	| devicetree DT_LABEL DT_REF nodedef
+	| devicetree DT_LABEL dt_ref nodedef
 		{
 			struct node *target = get_node_by_ref($1, $3);
 
@@ -189,7 +181,7 @@
 				ERROR(&@3, "Label or path %s not found", $3);
 			$$ = $1;
 		}
-	| devicetree DT_REF nodedef
+	| devicetree DT_PATH_REF nodedef
 		{
 			/*
 			 * We rely on the rule being always:
@@ -208,7 +200,26 @@
 			}
 			$$ = $1;
 		}
-	| devicetree DT_DEL_NODE DT_REF ';'
+	| devicetree DT_LABEL_REF nodedef
+		{
+			struct node *target = get_node_by_ref($1, $2);
+
+			if (target) {
+				merge_nodes(target, $3);
+			} else {
+				/*
+				 * We rely on the rule being always:
+				 *   versioninfo plugindecl memreserves devicetree
+				 * so $-1 is what we want (plugindecl)
+				 */
+				if ($<flags>-1 & DTSF_PLUGIN)
+					add_orphan_node($1, $3, $2);
+				else
+					ERROR(&@2, "Label or path %s not found", $2);
+			}
+			$$ = $1;
+		}
+	| devicetree DT_DEL_NODE dt_ref ';'
 		{
 			struct node *target = get_node_by_ref($1, $3);
 
@@ -220,7 +231,7 @@
 
 			$$ = $1;
 		}
-	| devicetree DT_OMIT_NO_REF DT_REF ';'
+	| devicetree DT_OMIT_NO_REF dt_ref ';'
 		{
 			struct node *target = get_node_by_ref($1, $3);
 
@@ -237,7 +248,7 @@
 nodedef:
 	  '{' proplist subnodes '}' ';'
 		{
-			$$ = build_node($2, $3);
+			$$ = build_node($2, $3, &@$);
 		}
 	;
 
@@ -255,11 +266,11 @@
 propdef:
 	  DT_PROPNODENAME '=' propdata ';'
 		{
-			$$ = build_property($1, $3);
+			$$ = build_property($1, $3, &@$);
 		}
 	| DT_PROPNODENAME ';'
 		{
-			$$ = build_property($1, empty_data);
+			$$ = build_property($1, empty_data, &@$);
 		}
 	| DT_DEL_PROP DT_PROPNODENAME ';'
 		{
@@ -285,8 +296,9 @@
 		{
 			$$ = data_merge($1, $3);
 		}
-	| propdataprefix DT_REF
+	| propdataprefix dt_ref
 		{
+			$1 = data_add_marker($1, TYPE_STRING, $2);
 			$$ = data_add_marker($1, REF_PATH, $2);
 		}
 	| propdataprefix DT_INCBIN '(' DT_STRING ',' integer_prim ',' integer_prim ')'
@@ -340,22 +352,27 @@
 	DT_BITS DT_LITERAL '<'
 		{
 			unsigned long long bits;
+			enum markertype type = TYPE_UINT32;
 
 			bits = $2;
 
-			if ((bits !=  8) && (bits != 16) &&
-			    (bits != 32) && (bits != 64)) {
+			switch (bits) {
+			case 8: type = TYPE_UINT8; break;
+			case 16: type = TYPE_UINT16; break;
+			case 32: type = TYPE_UINT32; break;
+			case 64: type = TYPE_UINT64; break;
+			default:
 				ERROR(&@2, "Array elements must be"
 				      " 8, 16, 32 or 64-bits");
 				bits = 32;
 			}
 
-			$$.data = empty_data;
+			$$.data = data_add_marker(empty_data, type, NULL);
 			$$.bits = bits;
 		}
 	| '<'
 		{
-			$$.data = empty_data;
+			$$.data = data_add_marker(empty_data, TYPE_UINT32, NULL);
 			$$.bits = 32;
 		}
 	| arrayprefix integer_prim
@@ -377,7 +394,7 @@
 
 			$$.data = data_append_integer($1.data, $2, $1.bits);
 		}
-	| arrayprefix DT_REF
+	| arrayprefix dt_ref
 		{
 			uint64_t val = ~0ULL >> (64 - $1.bits);
 
@@ -499,7 +516,7 @@
 bytestring:
 	  /* empty */
 		{
-			$$ = empty_data;
+			$$ = data_add_marker(empty_data, TYPE_UINT8, NULL);
 		}
 	| bytestring DT_BYTE
 		{
@@ -534,7 +551,7 @@
 		}
 	| DT_DEL_NODE DT_PROPNODENAME ';'
 		{
-			$$ = name_node(build_node_delete(), $2);
+			$$ = name_node(build_node_delete(&@$), $2);
 		}
 	| DT_OMIT_NO_REF subnode
 		{
diff --git a/scripts/dtc/dtc.c b/scripts/dtc/dtc.c
index c36994e..bdb3f59 100644
--- a/scripts/dtc/dtc.c
+++ b/scripts/dtc/dtc.c
@@ -1,21 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
- *
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 
 #include <sys/stat.h>
@@ -35,6 +20,8 @@
 int generate_symbols;	/* enable symbols & fixup support */
 int generate_fixups;		/* suppress generation of fixups on symbol support */
 int auto_label_aliases;		/* auto generate labels -> aliases */
+int annotate;		/* Level of annotation: 1 for input source location
+			   >1 for full input source location. */
 
 static int is_power_of_2(int x)
 {
@@ -60,7 +47,7 @@
 
 /* Usage related data. */
 static const char usage_synopsis[] = "dtc [options] <input file>";
-static const char usage_short_opts[] = "qI:O:o:V:d:R:S:p:a:fb:i:H:sW:E:@Ahv";
+static const char usage_short_opts[] = "qI:O:o:V:d:R:S:p:a:fb:i:H:sW:E:@AThv";
 static struct option const usage_long_opts[] = {
 	{"quiet",            no_argument, NULL, 'q'},
 	{"in-format",         a_argument, NULL, 'I'},
@@ -81,6 +68,7 @@
 	{"error",             a_argument, NULL, 'E'},
 	{"symbols",	     no_argument, NULL, '@'},
 	{"auto-alias",       no_argument, NULL, 'A'},
+	{"annotate",         no_argument, NULL, 'T'},
 	{"help",             no_argument, NULL, 'h'},
 	{"version",          no_argument, NULL, 'v'},
 	{NULL,               no_argument, NULL, 0x0},
@@ -95,6 +83,9 @@
 	"\n\tOutput formats are:\n"
 	 "\t\tdts - device tree source text\n"
 	 "\t\tdtb - device tree blob\n"
+#ifndef NO_YAML
+	 "\t\tyaml - device tree encoded as YAML\n"
+#endif
 	 "\t\tasm - assembler source",
 	"\n\tBlob version to produce, defaults to "stringify(DEFAULT_FDT_VERSION)" (for dtb and asm output)",
 	"\n\tOutput dependency file",
@@ -114,6 +105,7 @@
 	"\n\tEnable/disable errors (prefix with \"no-\")",
 	"\n\tEnable generation of symbols",
 	"\n\tEnable auto-alias of labels",
+	"\n\tAnnotate output .dts with input source file and line (-T -T for more details)",
 	"\n\tPrint this help and exit",
 	"\n\tPrint version and exit",
 	NULL,
@@ -128,6 +120,8 @@
 		return fallback;
 	if (!strcasecmp(s, ".dts"))
 		return "dts";
+	if (!strcasecmp(s, ".yaml"))
+		return "yaml";
 	if (!strcasecmp(s, ".dtb"))
 		return "dtb";
 	return fallback;
@@ -259,6 +253,9 @@
 		case 'A':
 			auto_label_aliases = 1;
 			break;
+		case 'T':
+			annotate++;
+			break;
 
 		case 'h':
 			usage(NULL);
@@ -297,6 +294,8 @@
 				outform = "dts";
 		}
 	}
+	if (annotate && (!streq(inform, "dts") || !streq(outform, "dts")))
+		die("--annotate requires -I dts -O dts\n");
 	if (streq(inform, "dts"))
 		dti = dt_from_source(arg);
 	else if (streq(inform, "fs"))
@@ -350,6 +349,12 @@
 
 	if (streq(outform, "dts")) {
 		dt_to_source(outf, dti);
+#ifndef NO_YAML
+	} else if (streq(outform, "yaml")) {
+		if (!streq(inform, "dts"))
+			die("YAML output format requires dts input format\n");
+		dt_to_yaml(outf, dti);
+#endif
 	} else if (streq(outform, "dtb")) {
 		dt_to_blob(outf, dti, outversion);
 	} else if (streq(outform, "asm")) {
diff --git a/scripts/dtc/dtc.h b/scripts/dtc/dtc.h
index 6d66770..6e74ece 100644
--- a/scripts/dtc/dtc.h
+++ b/scripts/dtc/dtc.h
@@ -1,24 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 #ifndef DTC_H
 #define DTC_H
 
 /*
  * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
- *
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 
 #include <stdio.h>
@@ -58,6 +43,7 @@
 extern int generate_symbols;	/* generate symbols for nodes with labels */
 extern int generate_fixups;	/* generate fixups */
 extern int auto_label_aliases;	/* auto generate labels -> aliases */
+extern int annotate;		/* annotate .dts with input source location */
 
 #define PHANDLE_LEGACY	0x1
 #define PHANDLE_EPAPR	0x2
@@ -74,10 +60,17 @@
 
 /* Data blobs */
 enum markertype {
+	TYPE_NONE,
 	REF_PHANDLE,
 	REF_PATH,
 	LABEL,
+	TYPE_UINT8,
+	TYPE_UINT16,
+	TYPE_UINT32,
+	TYPE_UINT64,
+	TYPE_STRING,
 };
+extern const char *markername(enum markertype markertype);
 
 struct  marker {
 	enum markertype type;
@@ -101,6 +94,8 @@
 	for_each_marker(m) \
 		if ((m)->type == (t))
 
+size_t type_marker_length(struct marker *m);
+
 void data_free(struct data d);
 
 struct data data_grow_for(struct data d, int xlen);
@@ -149,6 +144,7 @@
 	struct property *next;
 
 	struct label *labels;
+	struct srcpos *srcpos;
 };
 
 struct node {
@@ -168,6 +164,7 @@
 
 	struct label *labels;
 	const struct bus_type *bus;
+	struct srcpos *srcpos;
 
 	bool omit_if_unused, is_referenced;
 };
@@ -196,13 +193,15 @@
 void add_label(struct label **labels, char *label);
 void delete_labels(struct label **labels);
 
-struct property *build_property(char *name, struct data val);
+struct property *build_property(char *name, struct data val,
+				struct srcpos *srcpos);
 struct property *build_property_delete(char *name);
 struct property *chain_property(struct property *first, struct property *list);
 struct property *reverse_properties(struct property *first);
 
-struct node *build_node(struct property *proplist, struct node *children);
-struct node *build_node_delete(void);
+struct node *build_node(struct property *proplist, struct node *children,
+			struct srcpos *srcpos);
+struct node *build_node_delete(struct srcpos *srcpos);
 struct node *name_node(struct node *node, char *name);
 struct node *omit_node_if_unused(struct node *node);
 struct node *reference_node(struct node *node);
@@ -217,7 +216,8 @@
 void delete_node_by_name(struct node *parent, char *name);
 void delete_node(struct node *node);
 void append_to_property(struct node *node,
-			char *name, const void *data, int len);
+			char *name, const void *data, int len,
+			enum markertype type);
 
 const char *get_unitname(struct node *node);
 struct property *get_property(struct node *node, const char *propname);
@@ -290,6 +290,10 @@
 void dt_to_source(FILE *f, struct dt_info *dti);
 struct dt_info *dt_from_source(const char *f);
 
+/* YAML source */
+
+void dt_to_yaml(FILE *f, struct dt_info *dti);
+
 /* FS trees */
 
 struct dt_info *dt_from_fs(const char *dirname);
diff --git a/scripts/dtc/dtx_diff b/scripts/dtc/dtx_diff
index 8c4fbad..00fd473 100755
--- a/scripts/dtc/dtx_diff
+++ b/scripts/dtc/dtx_diff
@@ -1,10 +1,8 @@
 #! /bin/bash
+# SPDX-License-Identifier: GPL-2.0-only
 
 # Copyright (C) 2015 Frank Rowand
 #
-# This program 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; version 2 of the License.
 
 
 usage() {
@@ -21,6 +19,7 @@
         diff DTx_1 and DTx_2
 
 
+      --annotate    synonym for -T
        -f           print full dts in diff (--unified=99999)
        -h           synonym for --help
        -help        synonym for --help
@@ -28,6 +27,7 @@
        -s SRCTREE   linux kernel source tree is at path SRCTREE
                         (default is current directory)
        -S           linux kernel source tree is at root of current git repo
+       -T           Annotate output .dts with input source file and line (-T -T for more details)
        -u           unsorted, do not sort DTx
 
 
@@ -174,6 +174,7 @@
 
 # -----  start of script
 
+annotate=""
 cmd_diff=0
 diff_flags="-u"
 dtx_file_1=""
@@ -208,6 +209,14 @@
 		shift
 		;;
 
+	-T | --annotate )
+		if [ "${annotate}"  = "" ] ; then
+			annotate="-T"
+		elif [ "${annotate}"  = "-T" ] ; then
+			annotate="-T -T"
+		fi
+		shift
+		;;
 	-u )
 		dtc_sort=""
 		shift
@@ -327,7 +336,7 @@
 DTC="\
 	${DTC}                                     \
 	-i ${srctree}/scripts/dtc/include-prefixes \
-	-O dts -qq -f ${dtc_sort} -o -"
+	-O dts -qq -f ${dtc_sort} ${annotate} -o -"
 
 
 # -----  do the diff or decompile
diff --git a/scripts/dtc/fdtget.c b/scripts/dtc/fdtget.c
index c2fbab2..c922f82 100644
--- a/scripts/dtc/fdtget.c
+++ b/scripts/dtc/fdtget.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
  *
@@ -6,21 +7,6 @@
  * Based on code written by:
  *   Pantelis Antoniou <pantelis.antoniou@gmail.com> and
  *   Matthew McClintock <msm@freescale.com>
- *
- * This program 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 program 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 program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- * MA 02111-1307 USA
  */
 
 #include <assert.h>
diff --git a/scripts/dtc/fdtput.c b/scripts/dtc/fdtput.c
index f2197f5..a363c3c 100644
--- a/scripts/dtc/fdtput.c
+++ b/scripts/dtc/fdtput.c
@@ -1,20 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
- *
- * This program 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 program 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 program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- * MA 02111-1307 USA
  */
 
 #include <assert.h>
diff --git a/scripts/dtc/flattree.c b/scripts/dtc/flattree.c
index 8d268fb..bd6977e 100644
--- a/scripts/dtc/flattree.c
+++ b/scripts/dtc/flattree.c
@@ -1,21 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
- *
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 
 #include "dtc.h"
@@ -393,7 +378,7 @@
 			padlen = 0;
 			if (quiet < 1)
 				fprintf(stderr,
-					"Warning: blob size %d >= minimum size %d\n",
+					"Warning: blob size %"PRIu32" >= minimum size %d\n",
 					fdt32_to_cpu(fdt.totalsize), minsize);
 		}
 	}
@@ -525,7 +510,7 @@
 	fprintf(f, "/* Memory reserve map from source file */\n");
 
 	/*
-	 * Use .long on high and low halfs of u64s to avoid .quad
+	 * Use .long on high and low halves of u64s to avoid .quad
 	 * as it appears .quad isn't available in some assemblers.
 	 */
 	for (re = dti->reservelist; re; re = re->next) {
@@ -692,7 +677,7 @@
 
 	val = flat_read_data(dtbuf, proplen);
 
-	return build_property(name, val);
+	return build_property(name, val, NULL);
 }
 
 
@@ -750,7 +735,7 @@
 	char *flatname;
 	uint32_t val;
 
-	node = build_node(NULL, NULL);
+	node = build_node(NULL, NULL, NULL);
 
 	flatname = flat_read_string(dtbuf);
 
diff --git a/scripts/dtc/fstree.c b/scripts/dtc/fstree.c
index ae7d06c..9871689 100644
--- a/scripts/dtc/fstree.c
+++ b/scripts/dtc/fstree.c
@@ -1,21 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
- *
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 
 #include "dtc.h"
@@ -34,7 +19,7 @@
 	if (!d)
 		die("Couldn't opendir() \"%s\": %s\n", dirname, strerror(errno));
 
-	tree = build_node(NULL, NULL);
+	tree = build_node(NULL, NULL, NULL);
 
 	while ((de = readdir(d)) != NULL) {
 		char *tmpname;
@@ -60,7 +45,8 @@
 			} else {
 				prop = build_property(xstrdup(de->d_name),
 						      data_copy_file(pfile,
-								     st.st_size));
+								     st.st_size),
+						      NULL);
 				add_property(tree, prop);
 				fclose(pfile);
 			}
diff --git a/scripts/dtc/libfdt/Makefile.libfdt b/scripts/dtc/libfdt/Makefile.libfdt
index 098b3f3..e546397 100644
--- a/scripts/dtc/libfdt/Makefile.libfdt
+++ b/scripts/dtc/libfdt/Makefile.libfdt
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
 # Makefile.libfdt
 #
 # This is not a complete Makefile of itself.  Instead, it is designed to
@@ -9,3 +10,9 @@
 LIBFDT_SRCS = fdt.c fdt_ro.c fdt_wip.c fdt_sw.c fdt_rw.c fdt_strerror.c fdt_empty_tree.c \
 	fdt_addresses.c fdt_overlay.c
 LIBFDT_OBJS = $(LIBFDT_SRCS:%.c=%.o)
+LIBFDT_LIB = libfdt-$(DTC_VERSION).$(SHAREDLIB_EXT)
+
+libfdt_clean:
+	@$(VECHO) CLEAN "(libfdt)"
+	rm -f $(STD_CLEANFILES:%=$(LIBFDT_dir)/%)
+	rm -f $(LIBFDT_dir)/$(LIBFDT_soname)
diff --git a/scripts/dtc/libfdt/fdt.c b/scripts/dtc/libfdt/fdt.c
index 7855a17..179168e 100644
--- a/scripts/dtc/libfdt/fdt.c
+++ b/scripts/dtc/libfdt/fdt.c
@@ -1,52 +1,7 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
- *
- * libfdt is dual licensed: you can use it either under the terms of
- * the GPL, or the BSD license, at your option.
- *
- *  a) This library is free software; you can redistribute it and/or
- *     modify it under the terms of the GNU General Public License as
- *     published by the Free Software Foundation; either version 2 of the
- *     License, or (at your option) any later version.
- *
- *     This library is distributed in the hope that it will be useful,
- *     but WITHOUT ANY WARRANTY; without even the implied warranty of
- *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *     GNU General Public License for more details.
- *
- *     You should have received a copy of the GNU General Public
- *     License along with this library; if not, write to the Free
- *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
- *     MA 02110-1301 USA
- *
- * Alternatively,
- *
- *  b) Redistribution and use in source and binary forms, with or
- *     without modification, are permitted provided that the following
- *     conditions are met:
- *
- *     1. Redistributions of source code must retain the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer.
- *     2. Redistributions in binary form must reproduce the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer in the documentation and/or other materials
- *        provided with the distribution.
- *
- *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
- *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include "libfdt_env.h"
 
@@ -55,7 +10,12 @@
 
 #include "libfdt_internal.h"
 
-int fdt_check_header(const void *fdt)
+/*
+ * Minimal sanity check for a read-only tree. fdt_ro_probe_() checks
+ * that the given buffer contains what appears to be a flattened
+ * device tree with sane information in its header.
+ */
+int fdt_ro_probe_(const void *fdt)
 {
 	if (fdt_magic(fdt) == FDT_MAGIC) {
 		/* Complete tree */
@@ -74,6 +34,78 @@
 	return 0;
 }
 
+static int check_off_(uint32_t hdrsize, uint32_t totalsize, uint32_t off)
+{
+	return (off >= hdrsize) && (off <= totalsize);
+}
+
+static int check_block_(uint32_t hdrsize, uint32_t totalsize,
+			uint32_t base, uint32_t size)
+{
+	if (!check_off_(hdrsize, totalsize, base))
+		return 0; /* block start out of bounds */
+	if ((base + size) < base)
+		return 0; /* overflow */
+	if (!check_off_(hdrsize, totalsize, base + size))
+		return 0; /* block end out of bounds */
+	return 1;
+}
+
+size_t fdt_header_size_(uint32_t version)
+{
+	if (version <= 1)
+		return FDT_V1_SIZE;
+	else if (version <= 2)
+		return FDT_V2_SIZE;
+	else if (version <= 3)
+		return FDT_V3_SIZE;
+	else if (version <= 16)
+		return FDT_V16_SIZE;
+	else
+		return FDT_V17_SIZE;
+}
+
+int fdt_check_header(const void *fdt)
+{
+	size_t hdrsize;
+
+	if (fdt_magic(fdt) != FDT_MAGIC)
+		return -FDT_ERR_BADMAGIC;
+	hdrsize = fdt_header_size(fdt);
+	if ((fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION)
+	    || (fdt_last_comp_version(fdt) > FDT_LAST_SUPPORTED_VERSION))
+		return -FDT_ERR_BADVERSION;
+	if (fdt_version(fdt) < fdt_last_comp_version(fdt))
+		return -FDT_ERR_BADVERSION;
+
+	if ((fdt_totalsize(fdt) < hdrsize)
+	    || (fdt_totalsize(fdt) > INT_MAX))
+		return -FDT_ERR_TRUNCATED;
+
+	/* Bounds check memrsv block */
+	if (!check_off_(hdrsize, fdt_totalsize(fdt), fdt_off_mem_rsvmap(fdt)))
+		return -FDT_ERR_TRUNCATED;
+
+	/* Bounds check structure block */
+	if (fdt_version(fdt) < 17) {
+		if (!check_off_(hdrsize, fdt_totalsize(fdt),
+				fdt_off_dt_struct(fdt)))
+			return -FDT_ERR_TRUNCATED;
+	} else {
+		if (!check_block_(hdrsize, fdt_totalsize(fdt),
+				  fdt_off_dt_struct(fdt),
+				  fdt_size_dt_struct(fdt)))
+			return -FDT_ERR_TRUNCATED;
+	}
+
+	/* Bounds check strings block */
+	if (!check_block_(hdrsize, fdt_totalsize(fdt),
+			  fdt_off_dt_strings(fdt), fdt_size_dt_strings(fdt)))
+		return -FDT_ERR_TRUNCATED;
+
+	return 0;
+}
+
 const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int len)
 {
 	unsigned absoffset = offset + fdt_off_dt_struct(fdt);
@@ -244,7 +276,7 @@
 
 int fdt_move(const void *fdt, void *buf, int bufsize)
 {
-	FDT_CHECK_HEADER(fdt);
+	FDT_RO_PROBE(fdt);
 
 	if (fdt_totalsize(fdt) > bufsize)
 		return -FDT_ERR_NOSPACE;
diff --git a/scripts/dtc/libfdt/fdt.h b/scripts/dtc/libfdt/fdt.h
index 74961f9..f2e6880 100644
--- a/scripts/dtc/libfdt/fdt.h
+++ b/scripts/dtc/libfdt/fdt.h
@@ -1,55 +1,10 @@
+/* SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause) */
 #ifndef FDT_H
 #define FDT_H
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
  * Copyright 2012 Kim Phillips, Freescale Semiconductor.
- *
- * 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.
  */
 
 #ifndef __ASSEMBLY__
diff --git a/scripts/dtc/libfdt/fdt_addresses.c b/scripts/dtc/libfdt/fdt_addresses.c
index eff4dbc..d8ba8ec 100644
--- a/scripts/dtc/libfdt/fdt_addresses.c
+++ b/scripts/dtc/libfdt/fdt_addresses.c
@@ -1,52 +1,8 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2014 David Gibson <david@gibson.dropbear.id.au>
- *
- * 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.
+ * Copyright (C) 2018 embedded brains GmbH
  */
 #include "libfdt_env.h"
 
@@ -55,42 +11,89 @@
 
 #include "libfdt_internal.h"
 
-int fdt_address_cells(const void *fdt, int nodeoffset)
+static int fdt_cells(const void *fdt, int nodeoffset, const char *name)
 {
-	const fdt32_t *ac;
+	const fdt32_t *c;
 	int val;
 	int len;
 
-	ac = fdt_getprop(fdt, nodeoffset, "#address-cells", &len);
-	if (!ac)
-		return 2;
+	c = fdt_getprop(fdt, nodeoffset, name, &len);
+	if (!c)
+		return len;
 
-	if (len != sizeof(*ac))
+	if (len != sizeof(*c))
 		return -FDT_ERR_BADNCELLS;
 
-	val = fdt32_to_cpu(*ac);
+	val = fdt32_to_cpu(*c);
 	if ((val <= 0) || (val > FDT_MAX_NCELLS))
 		return -FDT_ERR_BADNCELLS;
 
 	return val;
 }
 
+int fdt_address_cells(const void *fdt, int nodeoffset)
+{
+	int val;
+
+	val = fdt_cells(fdt, nodeoffset, "#address-cells");
+	if (val == -FDT_ERR_NOTFOUND)
+		return 2;
+	return val;
+}
+
 int fdt_size_cells(const void *fdt, int nodeoffset)
 {
-	const fdt32_t *sc;
 	int val;
-	int len;
 
-	sc = fdt_getprop(fdt, nodeoffset, "#size-cells", &len);
-	if (!sc)
-		return 2;
-
-	if (len != sizeof(*sc))
-		return -FDT_ERR_BADNCELLS;
-
-	val = fdt32_to_cpu(*sc);
-	if ((val < 0) || (val > FDT_MAX_NCELLS))
-		return -FDT_ERR_BADNCELLS;
-
+	val = fdt_cells(fdt, nodeoffset, "#size-cells");
+	if (val == -FDT_ERR_NOTFOUND)
+		return 1;
 	return val;
 }
+
+/* This function assumes that [address|size]_cells is 1 or 2 */
+int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
+			     const char *name, uint64_t addr, uint64_t size)
+{
+	int addr_cells, size_cells, ret;
+	uint8_t data[sizeof(fdt64_t) * 2], *prop;
+
+	ret = fdt_address_cells(fdt, parent);
+	if (ret < 0)
+		return ret;
+	addr_cells = ret;
+
+	ret = fdt_size_cells(fdt, parent);
+	if (ret < 0)
+		return ret;
+	size_cells = ret;
+
+	/* check validity of address */
+	prop = data;
+	if (addr_cells == 1) {
+		if ((addr > UINT32_MAX) || ((UINT32_MAX + 1 - addr) < size))
+			return -FDT_ERR_BADVALUE;
+
+		fdt32_st(prop, (uint32_t)addr);
+	} else if (addr_cells == 2) {
+		fdt64_st(prop, addr);
+	} else {
+		return -FDT_ERR_BADNCELLS;
+	}
+
+	/* check validity of size */
+	prop += addr_cells * sizeof(fdt32_t);
+	if (size_cells == 1) {
+		if (size > UINT32_MAX)
+			return -FDT_ERR_BADVALUE;
+
+		fdt32_st(prop, (uint32_t)size);
+	} else if (size_cells == 2) {
+		fdt64_st(prop, size);
+	} else {
+		return -FDT_ERR_BADNCELLS;
+	}
+
+	return fdt_appendprop(fdt, nodeoffset, name, data,
+			      (addr_cells + size_cells) * sizeof(fdt32_t));
+}
diff --git a/scripts/dtc/libfdt/fdt_empty_tree.c b/scripts/dtc/libfdt/fdt_empty_tree.c
index f2ae9b7..49d54d4 100644
--- a/scripts/dtc/libfdt/fdt_empty_tree.c
+++ b/scripts/dtc/libfdt/fdt_empty_tree.c
@@ -1,52 +1,7 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2012 David Gibson, IBM Corporation.
- *
- * libfdt is dual licensed: you can use it either under the terms of
- * the GPL, or the BSD license, at your option.
- *
- *  a) This library is free software; you can redistribute it and/or
- *     modify it under the terms of the GNU General Public License as
- *     published by the Free Software Foundation; either version 2 of the
- *     License, or (at your option) any later version.
- *
- *     This library is distributed in the hope that it will be useful,
- *     but WITHOUT ANY WARRANTY; without even the implied warranty of
- *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *     GNU General Public License for more details.
- *
- *     You should have received a copy of the GNU General Public
- *     License along with this library; if not, write to the Free
- *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
- *     MA 02110-1301 USA
- *
- * Alternatively,
- *
- *  b) Redistribution and use in source and binary forms, with or
- *     without modification, are permitted provided that the following
- *     conditions are met:
- *
- *     1. Redistributions of source code must retain the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer.
- *     2. Redistributions in binary form must reproduce the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer in the documentation and/or other materials
- *        provided with the distribution.
- *
- *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
- *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include "libfdt_env.h"
 
diff --git a/scripts/dtc/libfdt/fdt_overlay.c b/scripts/dtc/libfdt/fdt_overlay.c
index bf75388..e97f12b 100644
--- a/scripts/dtc/libfdt/fdt_overlay.c
+++ b/scripts/dtc/libfdt/fdt_overlay.c
@@ -1,53 +1,8 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
 /*
  * 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"
 
@@ -93,11 +48,11 @@
  * @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
+ * device tree of a fragment, no matter how the actual targeting is
  * done (through a phandle or a path)
  *
  * returns:
- *      the targetted node offset in the base device tree
+ *      the targeted node offset in the base device tree
  *      Negative error code on error
  */
 static int overlay_get_target(const void *fdt, const void *fdto,
@@ -697,7 +652,7 @@
 	int len = 0, namelen;
 	const char *name;
 
-	FDT_CHECK_HEADER(fdt);
+	FDT_RO_PROBE(fdt);
 
 	for (;;) {
 		name = fdt_get_name(fdt, nodeoffset, &namelen);
@@ -863,11 +818,15 @@
 
 int fdt_overlay_apply(void *fdt, void *fdto)
 {
-	uint32_t delta = fdt_get_max_phandle(fdt);
+	uint32_t delta;
 	int ret;
 
-	FDT_CHECK_HEADER(fdt);
-	FDT_CHECK_HEADER(fdto);
+	FDT_RO_PROBE(fdt);
+	FDT_RO_PROBE(fdto);
+
+	ret = fdt_find_max_phandle(fdt, &delta);
+	if (ret)
+		goto err;
 
 	ret = overlay_adjust_local_phandles(fdto, delta);
 	if (ret)
diff --git a/scripts/dtc/libfdt/fdt_ro.c b/scripts/dtc/libfdt/fdt_ro.c
index dfb3236..6fd9ec1 100644
--- a/scripts/dtc/libfdt/fdt_ro.c
+++ b/scripts/dtc/libfdt/fdt_ro.c
@@ -1,52 +1,7 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
- *
- * libfdt is dual licensed: you can use it either under the terms of
- * the GPL, or the BSD license, at your option.
- *
- *  a) This library is free software; you can redistribute it and/or
- *     modify it under the terms of the GNU General Public License as
- *     published by the Free Software Foundation; either version 2 of the
- *     License, or (at your option) any later version.
- *
- *     This library is distributed in the hope that it will be useful,
- *     but WITHOUT ANY WARRANTY; without even the implied warranty of
- *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *     GNU General Public License for more details.
- *
- *     You should have received a copy of the GNU General Public
- *     License along with this library; if not, write to the Free
- *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
- *     MA 02110-1301 USA
- *
- * Alternatively,
- *
- *  b) Redistribution and use in source and binary forms, with or
- *     without modification, are permitted provided that the following
- *     conditions are met:
- *
- *     1. Redistributions of source code must retain the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer.
- *     2. Redistributions in binary form must reproduce the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer in the documentation and/or other materials
- *        provided with the distribution.
- *
- *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
- *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include "libfdt_env.h"
 
@@ -76,60 +31,156 @@
 		return 0;
 }
 
+const char *fdt_get_string(const void *fdt, int stroffset, int *lenp)
+{
+	uint32_t absoffset = stroffset + fdt_off_dt_strings(fdt);
+	size_t len;
+	int err;
+	const char *s, *n;
+
+	err = fdt_ro_probe_(fdt);
+	if (err != 0)
+		goto fail;
+
+	err = -FDT_ERR_BADOFFSET;
+	if (absoffset >= fdt_totalsize(fdt))
+		goto fail;
+	len = fdt_totalsize(fdt) - absoffset;
+
+	if (fdt_magic(fdt) == FDT_MAGIC) {
+		if (stroffset < 0)
+			goto fail;
+		if (fdt_version(fdt) >= 17) {
+			if (stroffset >= fdt_size_dt_strings(fdt))
+				goto fail;
+			if ((fdt_size_dt_strings(fdt) - stroffset) < len)
+				len = fdt_size_dt_strings(fdt) - stroffset;
+		}
+	} else if (fdt_magic(fdt) == FDT_SW_MAGIC) {
+		if ((stroffset >= 0)
+		    || (stroffset < -fdt_size_dt_strings(fdt)))
+			goto fail;
+		if ((-stroffset) < len)
+			len = -stroffset;
+	} else {
+		err = -FDT_ERR_INTERNAL;
+		goto fail;
+	}
+
+	s = (const char *)fdt + absoffset;
+	n = memchr(s, '\0', len);
+	if (!n) {
+		/* missing terminating NULL */
+		err = -FDT_ERR_TRUNCATED;
+		goto fail;
+	}
+
+	if (lenp)
+		*lenp = n - s;
+	return s;
+
+fail:
+	if (lenp)
+		*lenp = err;
+	return NULL;
+}
+
 const char *fdt_string(const void *fdt, int stroffset)
 {
-	return (const char *)fdt + fdt_off_dt_strings(fdt) + stroffset;
+	return fdt_get_string(fdt, stroffset, NULL);
 }
 
 static int fdt_string_eq_(const void *fdt, int stroffset,
 			  const char *s, int len)
 {
-	const char *p = fdt_string(fdt, stroffset);
+	int slen;
+	const char *p = fdt_get_string(fdt, stroffset, &slen);
 
-	return (strlen(p) == len) && (memcmp(p, s, len) == 0);
+	return p && (slen == len) && (memcmp(p, s, len) == 0);
 }
 
-uint32_t fdt_get_max_phandle(const void *fdt)
+int fdt_find_max_phandle(const void *fdt, uint32_t *phandle)
 {
-	uint32_t max_phandle = 0;
-	int offset;
+	uint32_t max = 0;
+	int offset = -1;
 
-	for (offset = fdt_next_node(fdt, -1, NULL);;
-	     offset = fdt_next_node(fdt, offset, NULL)) {
-		uint32_t phandle;
+	while (true) {
+		uint32_t value;
 
-		if (offset == -FDT_ERR_NOTFOUND)
-			return max_phandle;
+		offset = fdt_next_node(fdt, offset, NULL);
+		if (offset < 0) {
+			if (offset == -FDT_ERR_NOTFOUND)
+				break;
 
-		if (offset < 0)
-			return (uint32_t)-1;
+			return offset;
+		}
 
-		phandle = fdt_get_phandle(fdt, offset);
-		if (phandle == (uint32_t)-1)
-			continue;
+		value = fdt_get_phandle(fdt, offset);
 
-		if (phandle > max_phandle)
-			max_phandle = phandle;
+		if (value > max)
+			max = value;
 	}
 
+	if (phandle)
+		*phandle = max;
+
 	return 0;
 }
 
+int fdt_generate_phandle(const void *fdt, uint32_t *phandle)
+{
+	uint32_t max;
+	int err;
+
+	err = fdt_find_max_phandle(fdt, &max);
+	if (err < 0)
+		return err;
+
+	if (max == FDT_MAX_PHANDLE)
+		return -FDT_ERR_NOPHANDLES;
+
+	if (phandle)
+		*phandle = max + 1;
+
+	return 0;
+}
+
+static const struct fdt_reserve_entry *fdt_mem_rsv(const void *fdt, int n)
+{
+	int offset = n * sizeof(struct fdt_reserve_entry);
+	int absoffset = fdt_off_mem_rsvmap(fdt) + offset;
+
+	if (absoffset < fdt_off_mem_rsvmap(fdt))
+		return NULL;
+	if (absoffset > fdt_totalsize(fdt) - sizeof(struct fdt_reserve_entry))
+		return NULL;
+	return fdt_mem_rsv_(fdt, n);
+}
+
 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);
+	const struct fdt_reserve_entry *re;
+
+	FDT_RO_PROBE(fdt);
+	re = fdt_mem_rsv(fdt, n);
+	if (!re)
+		return -FDT_ERR_BADOFFSET;
+
+	*address = fdt64_ld(&re->address);
+	*size = fdt64_ld(&re->size);
 	return 0;
 }
 
 int fdt_num_mem_rsv(const void *fdt)
 {
-	int i = 0;
+	int i;
+	const struct fdt_reserve_entry *re;
 
-	while (fdt64_to_cpu(fdt_mem_rsv_(fdt, i)->size) != 0)
-		i++;
-	return i;
+	for (i = 0; (re = fdt_mem_rsv(fdt, i)) != NULL; i++) {
+		if (fdt64_ld(&re->size) == 0)
+			return i;
+	}
+	return -FDT_ERR_TRUNCATED;
 }
 
 static int nextprop_(const void *fdt, int offset)
@@ -161,7 +212,7 @@
 {
 	int depth;
 
-	FDT_CHECK_HEADER(fdt);
+	FDT_RO_PROBE(fdt);
 
 	for (depth = 0;
 	     (offset >= 0) && (depth >= 0);
@@ -187,7 +238,7 @@
 	const char *p = path;
 	int offset = 0;
 
-	FDT_CHECK_HEADER(fdt);
+	FDT_RO_PROBE(fdt);
 
 	/* see if we have an alias */
 	if (*path != '/') {
@@ -237,7 +288,7 @@
 	const char *nameptr;
 	int err;
 
-	if (((err = fdt_check_header(fdt)) != 0)
+	if (((err = fdt_ro_probe_(fdt)) != 0)
 	    || ((err = fdt_check_node_offset_(fdt, nodeoffset)) < 0))
 			goto fail;
 
@@ -303,7 +354,7 @@
 	prop = fdt_offset_ptr_(fdt, offset);
 
 	if (lenp)
-		*lenp = fdt32_to_cpu(prop->len);
+		*lenp = fdt32_ld(&prop->len);
 
 	return prop;
 }
@@ -340,7 +391,7 @@
 			offset = -FDT_ERR_INTERNAL;
 			break;
 		}
-		if (fdt_string_eq_(fdt, fdt32_to_cpu(prop->nameoff),
+		if (fdt_string_eq_(fdt, fdt32_ld(&prop->nameoff),
 				   name, namelen)) {
 			if (poffset)
 				*poffset = offset;
@@ -393,7 +444,7 @@
 
 	/* Handle realignment */
 	if (fdt_version(fdt) < 0x10 && (poffset + sizeof(*prop)) % 8 &&
-	    fdt32_to_cpu(prop->len) >= 8)
+	    fdt32_ld(&prop->len) >= 8)
 		return prop->data + 4;
 	return prop->data;
 }
@@ -406,12 +457,22 @@
 	prop = fdt_get_property_by_offset_(fdt, offset, lenp);
 	if (!prop)
 		return NULL;
-	if (namep)
-		*namep = fdt_string(fdt, fdt32_to_cpu(prop->nameoff));
+	if (namep) {
+		const char *name;
+		int namelen;
+		name = fdt_get_string(fdt, fdt32_ld(&prop->nameoff),
+				      &namelen);
+		if (!name) {
+			if (lenp)
+				*lenp = namelen;
+			return NULL;
+		}
+		*namep = name;
+	}
 
 	/* Handle realignment */
 	if (fdt_version(fdt) < 0x10 && (offset + sizeof(*prop)) % 8 &&
-	    fdt32_to_cpu(prop->len) >= 8)
+	    fdt32_ld(&prop->len) >= 8)
 		return prop->data + 4;
 	return prop->data;
 }
@@ -436,7 +497,7 @@
 			return 0;
 	}
 
-	return fdt32_to_cpu(*php);
+	return fdt32_ld(php);
 }
 
 const char *fdt_get_alias_namelen(const void *fdt,
@@ -462,7 +523,7 @@
 	int offset, depth, namelen;
 	const char *name;
 
-	FDT_CHECK_HEADER(fdt);
+	FDT_RO_PROBE(fdt);
 
 	if (buflen < 2)
 		return -FDT_ERR_NOSPACE;
@@ -514,7 +575,7 @@
 	int offset, depth;
 	int supernodeoffset = -FDT_ERR_INTERNAL;
 
-	FDT_CHECK_HEADER(fdt);
+	FDT_RO_PROBE(fdt);
 
 	if (supernodedepth < 0)
 		return -FDT_ERR_NOTFOUND;
@@ -573,7 +634,7 @@
 	const void *val;
 	int len;
 
-	FDT_CHECK_HEADER(fdt);
+	FDT_RO_PROBE(fdt);
 
 	/* FIXME: The algorithm here is pretty horrible: we scan each
 	 * property of a node in fdt_getprop(), then if that didn't
@@ -599,7 +660,7 @@
 	if ((phandle == 0) || (phandle == -1))
 		return -FDT_ERR_BADPHANDLE;
 
-	FDT_CHECK_HEADER(fdt);
+	FDT_RO_PROBE(fdt);
 
 	/* FIXME: The algorithm here is pretty horrible: we
 	 * potentially scan each property of a node in
@@ -752,7 +813,7 @@
 {
 	int offset, err;
 
-	FDT_CHECK_HEADER(fdt);
+	FDT_RO_PROBE(fdt);
 
 	/* FIXME: The algorithm here is pretty horrible: we scan each
 	 * property of a node in fdt_node_check_compatible(), then if
@@ -771,3 +832,66 @@
 
 	return offset; /* error from fdt_next_node() */
 }
+
+int fdt_check_full(const void *fdt, size_t bufsize)
+{
+	int err;
+	int num_memrsv;
+	int offset, nextoffset = 0;
+	uint32_t tag;
+	unsigned depth = 0;
+	const void *prop;
+	const char *propname;
+
+	if (bufsize < FDT_V1_SIZE)
+		return -FDT_ERR_TRUNCATED;
+	err = fdt_check_header(fdt);
+	if (err != 0)
+		return err;
+	if (bufsize < fdt_totalsize(fdt))
+		return -FDT_ERR_TRUNCATED;
+
+	num_memrsv = fdt_num_mem_rsv(fdt);
+	if (num_memrsv < 0)
+		return num_memrsv;
+
+	while (1) {
+		offset = nextoffset;
+		tag = fdt_next_tag(fdt, offset, &nextoffset);
+
+		if (nextoffset < 0)
+			return nextoffset;
+
+		switch (tag) {
+		case FDT_NOP:
+			break;
+
+		case FDT_END:
+			if (depth != 0)
+				return -FDT_ERR_BADSTRUCTURE;
+			return 0;
+
+		case FDT_BEGIN_NODE:
+			depth++;
+			if (depth > INT_MAX)
+				return -FDT_ERR_BADSTRUCTURE;
+			break;
+
+		case FDT_END_NODE:
+			if (depth == 0)
+				return -FDT_ERR_BADSTRUCTURE;
+			depth--;
+			break;
+
+		case FDT_PROP:
+			prop = fdt_getprop_by_offset(fdt, offset, &propname,
+						     &err);
+			if (!prop)
+				return err;
+			break;
+
+		default:
+			return -FDT_ERR_INTERNAL;
+		}
+	}
+}
diff --git a/scripts/dtc/libfdt/fdt_rw.c b/scripts/dtc/libfdt/fdt_rw.c
index 9b82905..8795947 100644
--- a/scripts/dtc/libfdt/fdt_rw.c
+++ b/scripts/dtc/libfdt/fdt_rw.c
@@ -1,52 +1,7 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
- *
- * libfdt is dual licensed: you can use it either under the terms of
- * the GPL, or the BSD license, at your option.
- *
- *  a) This library is free software; you can redistribute it and/or
- *     modify it under the terms of the GNU General Public License as
- *     published by the Free Software Foundation; either version 2 of the
- *     License, or (at your option) any later version.
- *
- *     This library is distributed in the hope that it will be useful,
- *     but WITHOUT ANY WARRANTY; without even the implied warranty of
- *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *     GNU General Public License for more details.
- *
- *     You should have received a copy of the GNU General Public
- *     License along with this library; if not, write to the Free
- *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
- *     MA 02110-1301 USA
- *
- * Alternatively,
- *
- *  b) Redistribution and use in source and binary forms, with or
- *     without modification, are permitted provided that the following
- *     conditions are met:
- *
- *     1. Redistributions of source code must retain the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer.
- *     2. Redistributions in binary form must reproduce the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer in the documentation and/or other materials
- *        provided with the distribution.
- *
- *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
- *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include "libfdt_env.h"
 
@@ -67,9 +22,9 @@
 		    (fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt)));
 }
 
-static int fdt_rw_check_header_(void *fdt)
+static int fdt_rw_probe_(void *fdt)
 {
-	FDT_CHECK_HEADER(fdt);
+	FDT_RO_PROBE(fdt);
 
 	if (fdt_version(fdt) < 17)
 		return -FDT_ERR_BADVERSION;
@@ -82,10 +37,10 @@
 	return 0;
 }
 
-#define FDT_RW_CHECK_HEADER(fdt) \
+#define FDT_RW_PROBE(fdt) \
 	{ \
 		int err_; \
-		if ((err_ = fdt_rw_check_header_(fdt)) != 0) \
+		if ((err_ = fdt_rw_probe_(fdt)) != 0) \
 			return err_; \
 	}
 
@@ -136,6 +91,14 @@
 	return 0;
 }
 
+/* Must only be used to roll back in case of error */
+static void fdt_del_last_string_(void *fdt, const char *s)
+{
+	int newlen = strlen(s) + 1;
+
+	fdt_set_size_dt_strings(fdt, fdt_size_dt_strings(fdt) - newlen);
+}
+
 static int fdt_splice_string_(void *fdt, int newlen)
 {
 	void *p = (char *)fdt
@@ -149,7 +112,7 @@
 	return 0;
 }
 
-static int fdt_find_add_string_(void *fdt, const char *s)
+static int fdt_find_add_string_(void *fdt, const char *s, int *allocated)
 {
 	char *strtab = (char *)fdt + fdt_off_dt_strings(fdt);
 	const char *p;
@@ -157,6 +120,8 @@
 	int len = strlen(s) + 1;
 	int err;
 
+	*allocated = 0;
+
 	p = fdt_find_string_(strtab, fdt_size_dt_strings(fdt), s);
 	if (p)
 		/* found it */
@@ -167,6 +132,8 @@
 	if (err)
 		return err;
 
+	*allocated = 1;
+
 	memcpy(new, s, len);
 	return (new - strtab);
 }
@@ -176,7 +143,7 @@
 	struct fdt_reserve_entry *re;
 	int err;
 
-	FDT_RW_CHECK_HEADER(fdt);
+	FDT_RW_PROBE(fdt);
 
 	re = fdt_mem_rsv_w_(fdt, fdt_num_mem_rsv(fdt));
 	err = fdt_splice_mem_rsv_(fdt, re, 0, 1);
@@ -192,7 +159,7 @@
 {
 	struct fdt_reserve_entry *re = fdt_mem_rsv_w_(fdt, n);
 
-	FDT_RW_CHECK_HEADER(fdt);
+	FDT_RW_PROBE(fdt);
 
 	if (n >= fdt_num_mem_rsv(fdt))
 		return -FDT_ERR_NOTFOUND;
@@ -225,11 +192,12 @@
 	int nextoffset;
 	int namestroff;
 	int err;
+	int allocated;
 
 	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, &allocated);
 	if (namestroff < 0)
 		return namestroff;
 
@@ -237,8 +205,11 @@
 	proplen = sizeof(**prop) + FDT_TAGALIGN(len);
 
 	err = fdt_splice_struct_(fdt, *prop, 0, proplen);
-	if (err)
+	if (err) {
+		if (allocated)
+			fdt_del_last_string_(fdt, name);
 		return err;
+	}
 
 	(*prop)->tag = cpu_to_fdt32(FDT_PROP);
 	(*prop)->nameoff = cpu_to_fdt32(namestroff);
@@ -252,7 +223,7 @@
 	int oldlen, newlen;
 	int err;
 
-	FDT_RW_CHECK_HEADER(fdt);
+	FDT_RW_PROBE(fdt);
 
 	namep = (char *)(uintptr_t)fdt_get_name(fdt, nodeoffset, &oldlen);
 	if (!namep)
@@ -275,7 +246,7 @@
 	struct fdt_property *prop;
 	int err;
 
-	FDT_RW_CHECK_HEADER(fdt);
+	FDT_RW_PROBE(fdt);
 
 	err = fdt_resize_property_(fdt, nodeoffset, name, len, &prop);
 	if (err == -FDT_ERR_NOTFOUND)
@@ -308,7 +279,7 @@
 	struct fdt_property *prop;
 	int err, oldlen, newlen;
 
-	FDT_RW_CHECK_HEADER(fdt);
+	FDT_RW_PROBE(fdt);
 
 	prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen);
 	if (prop) {
@@ -334,7 +305,7 @@
 	struct fdt_property *prop;
 	int len, proplen;
 
-	FDT_RW_CHECK_HEADER(fdt);
+	FDT_RW_PROBE(fdt);
 
 	prop = fdt_get_property_w(fdt, nodeoffset, name, &len);
 	if (!prop)
@@ -354,7 +325,7 @@
 	uint32_t tag;
 	fdt32_t *endtag;
 
-	FDT_RW_CHECK_HEADER(fdt);
+	FDT_RW_PROBE(fdt);
 
 	offset = fdt_subnode_offset_namelen(fdt, parentoffset, name, namelen);
 	if (offset >= 0)
@@ -394,7 +365,7 @@
 {
 	int endoffset;
 
-	FDT_RW_CHECK_HEADER(fdt);
+	FDT_RW_PROBE(fdt);
 
 	endoffset = fdt_node_end_offset_(fdt, nodeoffset);
 	if (endoffset < 0)
@@ -435,7 +406,7 @@
 	const char *fdtend = fdtstart + fdt_totalsize(fdt);
 	char *tmp;
 
-	FDT_CHECK_HEADER(fdt);
+	FDT_RO_PROBE(fdt);
 
 	mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
 		* sizeof(struct fdt_reserve_entry);
@@ -494,7 +465,7 @@
 {
 	int mem_rsv_size;
 
-	FDT_RW_CHECK_HEADER(fdt);
+	FDT_RW_PROBE(fdt);
 
 	mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
 		* sizeof(struct fdt_reserve_entry);
diff --git a/scripts/dtc/libfdt/fdt_strerror.c b/scripts/dtc/libfdt/fdt_strerror.c
index 9677a18..768db66 100644
--- a/scripts/dtc/libfdt/fdt_strerror.c
+++ b/scripts/dtc/libfdt/fdt_strerror.c
@@ -1,51 +1,7 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
- *
- * libfdt is dual licensed: you can use it either under the terms of
- * the GPL, or the BSD license, at your option.
- *
- *  a) This library is free software; you can redistribute it and/or
- *     modify it under the terms of the GNU General Public License as
- *     published by the Free Software Foundation; either version 2 of the
- *     License, or (at your option) any later version.
- *
- *     This library is distributed in the hope that it will be useful,
- *     but WITHOUT ANY WARRANTY; without even the implied warranty of
- *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *     GNU General Public License for more details.
- *
- *     You should have received a copy of the GNU General Public
- *     License along with this library; if not, write to the Free
- *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
- *     MA 02110-1301 USA
- *
- * Alternatively,
- *
- *  b) Redistribution and use in source and binary forms, with or
- *     without modification, are permitted provided that the following
- *     conditions are met:
- *
- *     1. Redistributions of source code must retain the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer.
- *     2. Redistributions in binary form must reproduce the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer in the documentation and/or other materials
- *        provided with the distribution.
- *
- *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
  *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include "libfdt_env.h"
@@ -82,6 +38,7 @@
 	FDT_ERRTABENT(FDT_ERR_BADVALUE),
 	FDT_ERRTABENT(FDT_ERR_BADOVERLAY),
 	FDT_ERRTABENT(FDT_ERR_NOPHANDLES),
+	FDT_ERRTABENT(FDT_ERR_BADFLAGS),
 };
 #define FDT_ERRTABSIZE	(sizeof(fdt_errtable) / sizeof(fdt_errtable[0]))
 
diff --git a/scripts/dtc/libfdt/fdt_sw.c b/scripts/dtc/libfdt/fdt_sw.c
index 6d33cc2..76bea22 100644
--- a/scripts/dtc/libfdt/fdt_sw.c
+++ b/scripts/dtc/libfdt/fdt_sw.c
@@ -1,52 +1,7 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
- *
- * libfdt is dual licensed: you can use it either under the terms of
- * the GPL, or the BSD license, at your option.
- *
- *  a) This library is free software; you can redistribute it and/or
- *     modify it under the terms of the GNU General Public License as
- *     published by the Free Software Foundation; either version 2 of the
- *     License, or (at your option) any later version.
- *
- *     This library is distributed in the hope that it will be useful,
- *     but WITHOUT ANY WARRANTY; without even the implied warranty of
- *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *     GNU General Public License for more details.
- *
- *     You should have received a copy of the GNU General Public
- *     License along with this library; if not, write to the Free
- *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
- *     MA 02110-1301 USA
- *
- * Alternatively,
- *
- *  b) Redistribution and use in source and binary forms, with or
- *     without modification, are permitted provided that the following
- *     conditions are met:
- *
- *     1. Redistributions of source code must retain the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer.
- *     2. Redistributions in binary form must reproduce the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer in the documentation and/or other materials
- *        provided with the distribution.
- *
- *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
- *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include "libfdt_env.h"
 
@@ -55,21 +10,83 @@
 
 #include "libfdt_internal.h"
 
-static int fdt_sw_check_header_(void *fdt)
+static int fdt_sw_probe_(void *fdt)
 {
-	if (fdt_magic(fdt) != FDT_SW_MAGIC)
+	if (fdt_magic(fdt) == FDT_MAGIC)
+		return -FDT_ERR_BADSTATE;
+	else if (fdt_magic(fdt) != FDT_SW_MAGIC)
 		return -FDT_ERR_BADMAGIC;
-	/* FIXME: should check more details about the header state */
 	return 0;
 }
 
-#define FDT_SW_CHECK_HEADER(fdt) \
+#define FDT_SW_PROBE(fdt) \
 	{ \
 		int err; \
-		if ((err = fdt_sw_check_header_(fdt)) != 0) \
+		if ((err = fdt_sw_probe_(fdt)) != 0) \
 			return err; \
 	}
 
+/* 'memrsv' state:	Initial state after fdt_create()
+ *
+ * Allowed functions:
+ *	fdt_add_reservmap_entry()
+ *	fdt_finish_reservemap()		[moves to 'struct' state]
+ */
+static int fdt_sw_probe_memrsv_(void *fdt)
+{
+	int err = fdt_sw_probe_(fdt);
+	if (err)
+		return err;
+
+	if (fdt_off_dt_strings(fdt) != 0)
+		return -FDT_ERR_BADSTATE;
+	return 0;
+}
+
+#define FDT_SW_PROBE_MEMRSV(fdt) \
+	{ \
+		int err; \
+		if ((err = fdt_sw_probe_memrsv_(fdt)) != 0) \
+			return err; \
+	}
+
+/* 'struct' state:	Enter this state after fdt_finish_reservemap()
+ *
+ * Allowed functions:
+ *	fdt_begin_node()
+ *	fdt_end_node()
+ *	fdt_property*()
+ *	fdt_finish()			[moves to 'complete' state]
+ */
+static int fdt_sw_probe_struct_(void *fdt)
+{
+	int err = fdt_sw_probe_(fdt);
+	if (err)
+		return err;
+
+	if (fdt_off_dt_strings(fdt) != fdt_totalsize(fdt))
+		return -FDT_ERR_BADSTATE;
+	return 0;
+}
+
+#define FDT_SW_PROBE_STRUCT(fdt) \
+	{ \
+		int err; \
+		if ((err = fdt_sw_probe_struct_(fdt)) != 0) \
+			return err; \
+	}
+
+static inline uint32_t sw_flags(void *fdt)
+{
+	/* assert: (fdt_magic(fdt) == FDT_SW_MAGIC) */
+	return fdt_last_comp_version(fdt);
+}
+
+/* 'complete' state:	Enter this state after fdt_finish()
+ *
+ * Allowed functions: none
+ */
+
 static void *fdt_grab_space_(void *fdt, size_t len)
 {
 	int offset = fdt_size_dt_struct(fdt);
@@ -85,38 +102,58 @@
 	return fdt_offset_ptr_w_(fdt, offset);
 }
 
-int fdt_create(void *buf, int bufsize)
+int fdt_create_with_flags(void *buf, int bufsize, uint32_t flags)
 {
+	const size_t hdrsize = FDT_ALIGN(sizeof(struct fdt_header),
+					 sizeof(struct fdt_reserve_entry));
 	void *fdt = buf;
 
-	if (bufsize < sizeof(struct fdt_header))
+	if (bufsize < hdrsize)
 		return -FDT_ERR_NOSPACE;
 
+	if (flags & ~FDT_CREATE_FLAGS_ALL)
+		return -FDT_ERR_BADFLAGS;
+
 	memset(buf, 0, bufsize);
 
+	/*
+	 * magic and last_comp_version keep intermediate state during the fdt
+	 * creation process, which is replaced with the proper FDT format by
+	 * fdt_finish().
+	 *
+	 * flags should be accessed with sw_flags().
+	 */
 	fdt_set_magic(fdt, FDT_SW_MAGIC);
 	fdt_set_version(fdt, FDT_LAST_SUPPORTED_VERSION);
-	fdt_set_last_comp_version(fdt, FDT_FIRST_SUPPORTED_VERSION);
+	fdt_set_last_comp_version(fdt, flags);
+
 	fdt_set_totalsize(fdt,  bufsize);
 
-	fdt_set_off_mem_rsvmap(fdt, FDT_ALIGN(sizeof(struct fdt_header),
-					      sizeof(struct fdt_reserve_entry)));
+	fdt_set_off_mem_rsvmap(fdt, hdrsize);
 	fdt_set_off_dt_struct(fdt, fdt_off_mem_rsvmap(fdt));
-	fdt_set_off_dt_strings(fdt, bufsize);
+	fdt_set_off_dt_strings(fdt, 0);
 
 	return 0;
 }
 
+int fdt_create(void *buf, int bufsize)
+{
+	return fdt_create_with_flags(buf, bufsize, 0);
+}
+
 int fdt_resize(void *fdt, void *buf, int bufsize)
 {
 	size_t headsize, tailsize;
 	char *oldtail, *newtail;
 
-	FDT_SW_CHECK_HEADER(fdt);
+	FDT_SW_PROBE(fdt);
 
-	headsize = fdt_off_dt_struct(fdt);
+	headsize = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt);
 	tailsize = fdt_size_dt_strings(fdt);
 
+	if ((headsize + tailsize) > fdt_totalsize(fdt))
+		return -FDT_ERR_INTERNAL;
+
 	if ((headsize + tailsize) > bufsize)
 		return -FDT_ERR_NOSPACE;
 
@@ -133,8 +170,9 @@
 		memmove(buf, fdt, headsize);
 	}
 
-	fdt_set_off_dt_strings(buf, bufsize);
 	fdt_set_totalsize(buf, bufsize);
+	if (fdt_off_dt_strings(buf))
+		fdt_set_off_dt_strings(buf, bufsize);
 
 	return 0;
 }
@@ -144,10 +182,7 @@
 	struct fdt_reserve_entry *re;
 	int offset;
 
-	FDT_SW_CHECK_HEADER(fdt);
-
-	if (fdt_size_dt_struct(fdt))
-		return -FDT_ERR_BADSTATE;
+	FDT_SW_PROBE_MEMRSV(fdt);
 
 	offset = fdt_off_dt_struct(fdt);
 	if ((offset + sizeof(*re)) > fdt_totalsize(fdt))
@@ -164,16 +199,23 @@
 
 int fdt_finish_reservemap(void *fdt)
 {
-	return fdt_add_reservemap_entry(fdt, 0, 0);
+	int err = fdt_add_reservemap_entry(fdt, 0, 0);
+
+	if (err)
+		return err;
+
+	fdt_set_off_dt_strings(fdt, fdt_totalsize(fdt));
+	return 0;
 }
 
 int fdt_begin_node(void *fdt, const char *name)
 {
 	struct fdt_node_header *nh;
-	int namelen = strlen(name) + 1;
+	int namelen;
 
-	FDT_SW_CHECK_HEADER(fdt);
+	FDT_SW_PROBE_STRUCT(fdt);
 
+	namelen = strlen(name) + 1;
 	nh = fdt_grab_space_(fdt, sizeof(*nh) + FDT_TAGALIGN(namelen));
 	if (! nh)
 		return -FDT_ERR_NOSPACE;
@@ -187,7 +229,7 @@
 {
 	fdt32_t *en;
 
-	FDT_SW_CHECK_HEADER(fdt);
+	FDT_SW_PROBE_STRUCT(fdt);
 
 	en = fdt_grab_space_(fdt, FDT_TAGSIZE);
 	if (! en)
@@ -197,19 +239,13 @@
 	return 0;
 }
 
-static int fdt_find_add_string_(void *fdt, const char *s)
+static int fdt_add_string_(void *fdt, const char *s)
 {
 	char *strtab = (char *)fdt + fdt_totalsize(fdt);
-	const char *p;
 	int strtabsize = fdt_size_dt_strings(fdt);
 	int len = strlen(s) + 1;
 	int struct_top, offset;
 
-	p = fdt_find_string_(strtab - strtabsize, strtabsize, s);
-	if (p)
-		return p - strtab;
-
-	/* Add it */
 	offset = -strtabsize - len;
 	struct_top = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt);
 	if (fdt_totalsize(fdt) + offset < struct_top)
@@ -220,20 +256,56 @@
 	return offset;
 }
 
+/* Must only be used to roll back in case of error */
+static void fdt_del_last_string_(void *fdt, const char *s)
+{
+	int strtabsize = fdt_size_dt_strings(fdt);
+	int len = strlen(s) + 1;
+
+	fdt_set_size_dt_strings(fdt, strtabsize - len);
+}
+
+static int fdt_find_add_string_(void *fdt, const char *s, int *allocated)
+{
+	char *strtab = (char *)fdt + fdt_totalsize(fdt);
+	int strtabsize = fdt_size_dt_strings(fdt);
+	const char *p;
+
+	*allocated = 0;
+
+	p = fdt_find_string_(strtab - strtabsize, strtabsize, s);
+	if (p)
+		return p - strtab;
+
+	*allocated = 1;
+
+	return fdt_add_string_(fdt, s);
+}
+
 int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp)
 {
 	struct fdt_property *prop;
 	int nameoff;
+	int allocated;
 
-	FDT_SW_CHECK_HEADER(fdt);
+	FDT_SW_PROBE_STRUCT(fdt);
 
-	nameoff = fdt_find_add_string_(fdt, name);
+	/* String de-duplication can be slow, _NO_NAME_DEDUP skips it */
+	if (sw_flags(fdt) & FDT_CREATE_FLAG_NO_NAME_DEDUP) {
+		allocated = 1;
+		nameoff = fdt_add_string_(fdt, name);
+	} else {
+		nameoff = fdt_find_add_string_(fdt, name, &allocated);
+	}
 	if (nameoff == 0)
 		return -FDT_ERR_NOSPACE;
 
 	prop = fdt_grab_space_(fdt, sizeof(*prop) + FDT_TAGALIGN(len));
-	if (! prop)
+	if (! prop) {
+		if (allocated)
+			fdt_del_last_string_(fdt, name);
 		return -FDT_ERR_NOSPACE;
+	}
 
 	prop->tag = cpu_to_fdt32(FDT_PROP);
 	prop->nameoff = cpu_to_fdt32(nameoff);
@@ -262,7 +334,7 @@
 	uint32_t tag;
 	int offset, nextoffset;
 
-	FDT_SW_CHECK_HEADER(fdt);
+	FDT_SW_PROBE_STRUCT(fdt);
 
 	/* Add terminator */
 	end = fdt_grab_space_(fdt, sizeof(*end));
@@ -295,6 +367,10 @@
 
 	/* Finally, adjust the header */
 	fdt_set_totalsize(fdt, newstroffset + fdt_size_dt_strings(fdt));
+
+	/* And fix up fields that were keeping intermediate state. */
+	fdt_set_last_comp_version(fdt, FDT_FIRST_SUPPORTED_VERSION);
 	fdt_set_magic(fdt, FDT_MAGIC);
+
 	return 0;
 }
diff --git a/scripts/dtc/libfdt/fdt_wip.c b/scripts/dtc/libfdt/fdt_wip.c
index 534c1cb..f64139e 100644
--- a/scripts/dtc/libfdt/fdt_wip.c
+++ b/scripts/dtc/libfdt/fdt_wip.c
@@ -1,52 +1,7 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
- *
- * libfdt is dual licensed: you can use it either under the terms of
- * the GPL, or the BSD license, at your option.
- *
- *  a) This library is free software; you can redistribute it and/or
- *     modify it under the terms of the GNU General Public License as
- *     published by the Free Software Foundation; either version 2 of the
- *     License, or (at your option) any later version.
- *
- *     This library is distributed in the hope that it will be useful,
- *     but WITHOUT ANY WARRANTY; without even the implied warranty of
- *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *     GNU General Public License for more details.
- *
- *     You should have received a copy of the GNU General Public
- *     License along with this library; if not, write to the Free
- *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
- *     MA 02110-1301 USA
- *
- * Alternatively,
- *
- *  b) Redistribution and use in source and binary forms, with or
- *     without modification, are permitted provided that the following
- *     conditions are met:
- *
- *     1. Redistributions of source code must retain the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer.
- *     2. Redistributions in binary form must reproduce the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer in the documentation and/or other materials
- *        provided with the distribution.
- *
- *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
- *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include "libfdt_env.h"
 
diff --git a/scripts/dtc/libfdt/libfdt.h b/scripts/dtc/libfdt/libfdt.h
index 1e27780..7b5ffd1 100644
--- a/scripts/dtc/libfdt/libfdt.h
+++ b/scripts/dtc/libfdt/libfdt.h
@@ -1,54 +1,9 @@
+/* SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause) */
 #ifndef LIBFDT_H
 #define LIBFDT_H
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
- *
- * libfdt is dual licensed: you can use it either under the terms of
- * the GPL, or the BSD license, at your option.
- *
- *  a) This library is free software; you can redistribute it and/or
- *     modify it under the terms of the GNU General Public License as
- *     published by the Free Software Foundation; either version 2 of the
- *     License, or (at your option) any later version.
- *
- *     This library is distributed in the hope that it will be useful,
- *     but WITHOUT ANY WARRANTY; without even the implied warranty of
- *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *     GNU General Public License for more details.
- *
- *     You should have received a copy of the GNU General Public
- *     License along with this library; if not, write to the Free
- *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
- *     MA 02110-1301 USA
- *
- * Alternatively,
- *
- *  b) Redistribution and use in source and binary forms, with or
- *     without modification, are permitted provided that the following
- *     conditions are met:
- *
- *     1. Redistributions of source code must retain the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer.
- *     2. Redistributions in binary form must reproduce the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer in the documentation and/or other materials
- *        provided with the distribution.
- *
- *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
- *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "libfdt_env.h"
@@ -90,8 +45,9 @@
 
 /* Error codes: codes for bad device tree blobs */
 #define FDT_ERR_TRUNCATED	8
-	/* FDT_ERR_TRUNCATED: Structure block of the given device tree
-	 * ends without an FDT_END tag. */
+	/* FDT_ERR_TRUNCATED: FDT or a sub-block is improperly
+	 * terminated (overflows, goes outside allowed bounds, or
+	 * isn't properly terminated).  */
 #define FDT_ERR_BADMAGIC	9
 	/* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
 	 * device tree at all - it is missing the flattened device
@@ -137,7 +93,15 @@
 	/* FDT_ERR_NOPHANDLES: The device tree doesn't have any
 	 * phandle available anymore without causing an overflow */
 
-#define FDT_ERR_MAX		17
+#define FDT_ERR_BADFLAGS	18
+	/* FDT_ERR_BADFLAGS: The function was passed a flags field that
+	 * contains invalid flags or an invalid combination of flags. */
+
+#define FDT_ERR_MAX		18
+
+/* constants */
+#define FDT_MAX_PHANDLE 0xfffffffe
+	/* Valid values for phandles range from 1 to 2^32-2. */
 
 /**********************************************************************/
 /* Low-level functions (you probably don't need these)                */
@@ -153,6 +117,61 @@
 
 uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
 
+/*
+ * Alignment helpers:
+ *     These helpers access words from a device tree blob.  They're
+ *     built to work even with unaligned pointers on platforms (ike
+ *     ARM) that don't like unaligned loads and stores
+ */
+
+static inline uint32_t fdt32_ld(const fdt32_t *p)
+{
+	const uint8_t *bp = (const uint8_t *)p;
+
+	return ((uint32_t)bp[0] << 24)
+		| ((uint32_t)bp[1] << 16)
+		| ((uint32_t)bp[2] << 8)
+		| bp[3];
+}
+
+static inline void fdt32_st(void *property, uint32_t value)
+{
+	uint8_t *bp = property;
+
+	bp[0] = value >> 24;
+	bp[1] = (value >> 16) & 0xff;
+	bp[2] = (value >> 8) & 0xff;
+	bp[3] = value & 0xff;
+}
+
+static inline uint64_t fdt64_ld(const fdt64_t *p)
+{
+	const uint8_t *bp = (const uint8_t *)p;
+
+	return ((uint64_t)bp[0] << 56)
+		| ((uint64_t)bp[1] << 48)
+		| ((uint64_t)bp[2] << 40)
+		| ((uint64_t)bp[3] << 32)
+		| ((uint64_t)bp[4] << 24)
+		| ((uint64_t)bp[5] << 16)
+		| ((uint64_t)bp[6] << 8)
+		| bp[7];
+}
+
+static inline void fdt64_st(void *property, uint64_t value)
+{
+	uint8_t *bp = property;
+
+	bp[0] = value >> 56;
+	bp[1] = (value >> 48) & 0xff;
+	bp[2] = (value >> 40) & 0xff;
+	bp[3] = (value >> 32) & 0xff;
+	bp[4] = (value >> 24) & 0xff;
+	bp[5] = (value >> 16) & 0xff;
+	bp[6] = (value >> 8) & 0xff;
+	bp[7] = value & 0xff;
+}
+
 /**********************************************************************/
 /* Traversal functions                                                */
 /**********************************************************************/
@@ -195,7 +214,7 @@
  *		...
  *	}
  *
- *	if ((node < 0) && (node != -FDT_ERR_NOT_FOUND)) {
+ *	if ((node < 0) && (node != -FDT_ERR_NOTFOUND)) {
  *		Error handling
  *	}
  *
@@ -213,7 +232,7 @@
 /* General functions                                                  */
 /**********************************************************************/
 #define fdt_get_header(fdt, field) \
-	(fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
+	(fdt32_ld(&((const struct fdt_header *)(fdt))->field))
 #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))
@@ -244,18 +263,31 @@
 #undef fdt_set_hdr_
 
 /**
- * fdt_check_header - sanity check a device tree or possible device tree
+ * fdt_header_size - return the size of the tree's header
+ * @fdt: pointer to a flattened device tree
+ */
+size_t fdt_header_size_(uint32_t version);
+static inline size_t fdt_header_size(const void *fdt)
+{
+	return fdt_header_size_(fdt_version(fdt));
+}
+
+/**
+ * fdt_check_header - sanity check a device tree header
+
  * @fdt: pointer to data which might be a flattened device tree
  *
  * fdt_check_header() checks that the given buffer contains what
- * appears to be a flattened device tree with sane information in its
- * header.
+ * appears to be a flattened device tree, and that the header contains
+ * valid information (to the extent that can be determined from the
+ * header alone).
  *
  * returns:
  *     0, if the buffer appears to contain a valid device tree
  *     -FDT_ERR_BADMAGIC,
  *     -FDT_ERR_BADVERSION,
- *     -FDT_ERR_BADSTATE, standard meanings, as above
+ *     -FDT_ERR_BADSTATE,
+ *     -FDT_ERR_TRUNCATED, standard meanings, as above
  */
 int fdt_check_header(const void *fdt);
 
@@ -284,6 +316,24 @@
 /* Read-only functions                                                */
 /**********************************************************************/
 
+int fdt_check_full(const void *fdt, size_t bufsize);
+
+/**
+ * fdt_get_string - retrieve a string from the strings block of a device tree
+ * @fdt: pointer to the device tree blob
+ * @stroffset: offset of the string within the strings block (native endian)
+ * @lenp: optional pointer to return the string's length
+ *
+ * fdt_get_string() retrieves a pointer to a single string from the
+ * strings block of the device tree blob at fdt, and optionally also
+ * returns the string's length in *lenp.
+ *
+ * returns:
+ *     a pointer to the string, on success
+ *     NULL, if stroffset is out of bounds, or doesn't point to a valid string
+ */
+const char *fdt_get_string(const void *fdt, int stroffset, int *lenp);
+
 /**
  * fdt_string - retrieve a string from the strings block of a device tree
  * @fdt: pointer to the device tree blob
@@ -294,11 +344,25 @@
  *
  * returns:
  *     a pointer to the string, on success
- *     NULL, if stroffset is out of bounds
+ *     NULL, if stroffset is out of bounds, or doesn't point to a valid string
  */
 const char *fdt_string(const void *fdt, int stroffset);
 
 /**
+ * fdt_find_max_phandle - find and return the highest phandle in a tree
+ * @fdt: pointer to the device tree blob
+ * @phandle: return location for the highest phandle value found in the tree
+ *
+ * fdt_find_max_phandle() finds the highest phandle value in the given device
+ * tree. The value returned in @phandle is only valid if the function returns
+ * success.
+ *
+ * returns:
+ *     0 on success or a negative error code on failure
+ */
+int fdt_find_max_phandle(const void *fdt, uint32_t *phandle);
+
+/**
  * fdt_get_max_phandle - retrieves the highest phandle in a tree
  * @fdt: pointer to the device tree blob
  *
@@ -306,12 +370,39 @@
  * device tree. This will ignore badly formatted phandles, or phandles
  * with a value of 0 or -1.
  *
+ * This function is deprecated in favour of fdt_find_max_phandle().
+ *
  * 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);
+static inline uint32_t fdt_get_max_phandle(const void *fdt)
+{
+	uint32_t phandle;
+	int err;
+
+	err = fdt_find_max_phandle(fdt, &phandle);
+	if (err < 0)
+		return (uint32_t)-1;
+
+	return phandle;
+}
+
+/**
+ * fdt_generate_phandle - return a new, unused phandle for a device tree blob
+ * @fdt: pointer to the device tree blob
+ * @phandle: return location for the new phandle
+ *
+ * Walks the device tree blob and looks for the highest phandle value. On
+ * success, the new, unused phandle value (one higher than the previously
+ * highest phandle value in the device tree blob) will be returned in the
+ * @phandle parameter.
+ *
+ * Returns:
+ *   0 on success or a negative error-code on failure
+ */
+int fdt_generate_phandle(const void *fdt, uint32_t *phandle);
 
 /**
  * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
@@ -503,7 +594,7 @@
  *		...
  *	}
  *
- *	if ((property < 0) && (property != -FDT_ERR_NOT_FOUND)) {
+ *	if ((property < 0) && (property != -FDT_ERR_NOTFOUND)) {
  *		Error handling
  *	}
  *
@@ -606,7 +697,7 @@
 /**
  * fdt_getprop_by_offset - retrieve the value of a property at a given offset
  * @fdt: pointer to the device tree blob
- * @ffset: offset of the property to read
+ * @offset: offset of the property to read
  * @namep: pointer to a string variable (will be overwritten) or NULL
  * @lenp: pointer to an integer variable (will be overwritten) or NULL
  *
@@ -1090,7 +1181,7 @@
  *
  * returns:
  *	0 <= n < FDT_MAX_NCELLS, on success
- *      2, if the node has no #address-cells property
+ *      1, if the node has no #size-cells property
  *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
  *		#size-cells property
  *	-FDT_ERR_BADMAGIC,
@@ -1297,7 +1388,45 @@
 /* Sequential write functions                                         */
 /**********************************************************************/
 
+/* fdt_create_with_flags flags */
+#define FDT_CREATE_FLAG_NO_NAME_DEDUP 0x1
+	/* FDT_CREATE_FLAG_NO_NAME_DEDUP: Do not try to de-duplicate property
+	 * names in the fdt. This can result in faster creation times, but
+	 * a larger fdt. */
+
+#define FDT_CREATE_FLAGS_ALL	(FDT_CREATE_FLAG_NO_NAME_DEDUP)
+
+/**
+ * fdt_create_with_flags - begin creation of a new fdt
+ * @fdt: pointer to memory allocated where fdt will be created
+ * @bufsize: size of the memory space at fdt
+ * @flags: a valid combination of FDT_CREATE_FLAG_ flags, or 0.
+ *
+ * fdt_create_with_flags() begins the process of creating a new fdt with
+ * the sequential write interface.
+ *
+ * fdt creation process must end with fdt_finished() to produce a valid fdt.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
+ *	-FDT_ERR_BADFLAGS, flags is not valid
+ */
+int fdt_create_with_flags(void *buf, int bufsize, uint32_t flags);
+
+/**
+ * fdt_create - begin creation of a new fdt
+ * @fdt: pointer to memory allocated where fdt will be created
+ * @bufsize: size of the memory space at fdt
+ *
+ * fdt_create() is equivalent to fdt_create_with_flags() with flags=0.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
+ */
 int fdt_create(void *buf, int bufsize);
+
 int fdt_resize(void *fdt, void *buf, int bufsize);
 int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
 int fdt_finish_reservemap(void *fdt);
@@ -1313,10 +1442,13 @@
 	fdt64_t tmp = cpu_to_fdt64(val);
 	return fdt_property(fdt, name, &tmp, sizeof(tmp));
 }
+
+#ifndef SWIG /* Not available in Python */
 static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
 {
 	return fdt_property_u32(fdt, name, val);
 }
+#endif
 
 /**
  * fdt_property_placeholder - add a new property and return a ptr to its value
@@ -1766,6 +1898,43 @@
 	fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
 
 /**
+ * fdt_appendprop_addrrange - append a address range property
+ * @fdt: pointer to the device tree blob
+ * @parent: offset of the parent node
+ * @nodeoffset: offset of the node to add a property at
+ * @name: name of property
+ * @addr: start address of a given range
+ * @size: size of a given range
+ *
+ * fdt_appendprop_addrrange() appends an address range value (start
+ * address and size) to the value of the named property in the given
+ * node, or creates a new property with that value if it does not
+ * already exist.
+ * If "name" is not specified, a default "reg" is used.
+ * Cell sizes are determined by parent's #address-cells and #size-cells.
+ *
+ * This function may insert data into the blob, and will therefore
+ * change the offsets of some existing nodes.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
+ *		#address-cells property
+ *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADVALUE, addr or size doesn't fit to respective cells size
+ *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
+ *		contain a new property
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
+			     const char *name, uint64_t addr, uint64_t size);
+
+/**
  * fdt_delprop - delete a property
  * @fdt: pointer to the device tree blob
  * @nodeoffset: offset of the node whose property to nop
diff --git a/scripts/dtc/libfdt/libfdt_env.h b/scripts/dtc/libfdt/libfdt_env.h
index bd24746..73b6d40 100644
--- a/scripts/dtc/libfdt/libfdt_env.h
+++ b/scripts/dtc/libfdt/libfdt_env.h
@@ -1,61 +1,18 @@
+/* SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause) */
 #ifndef LIBFDT_ENV_H
 #define LIBFDT_ENV_H
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
  * Copyright 2012 Kim Phillips, Freescale Semiconductor.
- *
- * 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 <stdbool.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
+#include <limits.h>
 
 #ifdef __CHECKER__
 #define FDT_FORCE __attribute__((force))
diff --git a/scripts/dtc/libfdt/libfdt_internal.h b/scripts/dtc/libfdt/libfdt_internal.h
index 7681e19..7830e55 100644
--- a/scripts/dtc/libfdt/libfdt_internal.h
+++ b/scripts/dtc/libfdt/libfdt_internal.h
@@ -1,64 +1,20 @@
+/* SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause) */
 #ifndef LIBFDT_INTERNAL_H
 #define LIBFDT_INTERNAL_H
 /*
  * libfdt - Flat Device Tree manipulation
  * Copyright (C) 2006 David Gibson, IBM Corporation.
- *
- * libfdt is dual licensed: you can use it either under the terms of
- * the GPL, or the BSD license, at your option.
- *
- *  a) This library is free software; you can redistribute it and/or
- *     modify it under the terms of the GNU General Public License as
- *     published by the Free Software Foundation; either version 2 of the
- *     License, or (at your option) any later version.
- *
- *     This library is distributed in the hope that it will be useful,
- *     but WITHOUT ANY WARRANTY; without even the implied warranty of
- *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *     GNU General Public License for more details.
- *
- *     You should have received a copy of the GNU General Public
- *     License along with this library; if not, write to the Free
- *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
- *     MA 02110-1301 USA
- *
- * Alternatively,
- *
- *  b) Redistribution and use in source and binary forms, with or
- *     without modification, are permitted provided that the following
- *     conditions are met:
- *
- *     1. Redistributions of source code must retain the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer.
- *     2. Redistributions in binary form must reproduce the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer in the documentation and/or other materials
- *        provided with the distribution.
- *
- *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
- *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include <fdt.h>
 
 #define FDT_ALIGN(x, a)		(((x) + (a) - 1) & ~((a) - 1))
 #define FDT_TAGALIGN(x)		(FDT_ALIGN((x), FDT_TAGSIZE))
 
-#define FDT_CHECK_HEADER(fdt) \
+int fdt_ro_probe_(const void *fdt);
+#define FDT_RO_PROBE(fdt)			\
 	{ \
 		int err_; \
-		if ((err_ = fdt_check_header(fdt)) != 0) \
+		if ((err_ = fdt_ro_probe_(fdt)) != 0)	\
 			return err_; \
 	}
 
diff --git a/scripts/dtc/livetree.c b/scripts/dtc/livetree.c
index 6e4c367..0c03999 100644
--- a/scripts/dtc/livetree.c
+++ b/scripts/dtc/livetree.c
@@ -1,24 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
- *
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 
 #include "dtc.h"
+#include "srcpos.h"
 
 /*
  * Tree building functions
@@ -50,7 +36,8 @@
 		label->deleted = 1;
 }
 
-struct property *build_property(char *name, struct data val)
+struct property *build_property(char *name, struct data val,
+				struct srcpos *srcpos)
 {
 	struct property *new = xmalloc(sizeof(*new));
 
@@ -58,6 +45,7 @@
 
 	new->name = name;
 	new->val = val;
+	new->srcpos = srcpos_copy(srcpos);
 
 	return new;
 }
@@ -97,7 +85,8 @@
 	return head;
 }
 
-struct node *build_node(struct property *proplist, struct node *children)
+struct node *build_node(struct property *proplist, struct node *children,
+			struct srcpos *srcpos)
 {
 	struct node *new = xmalloc(sizeof(*new));
 	struct node *child;
@@ -106,6 +95,7 @@
 
 	new->proplist = reverse_properties(proplist);
 	new->children = children;
+	new->srcpos = srcpos_copy(srcpos);
 
 	for_each_child(new, child) {
 		child->parent = new;
@@ -114,13 +104,14 @@
 	return new;
 }
 
-struct node *build_node_delete(void)
+struct node *build_node_delete(struct srcpos *srcpos)
 {
 	struct node *new = xmalloc(sizeof(*new));
 
 	memset(new, 0, sizeof(*new));
 
 	new->deleted = 1;
+	new->srcpos = srcpos_copy(srcpos);
 
 	return new;
 }
@@ -183,6 +174,8 @@
 
 				old_prop->val = new_prop->val;
 				old_prop->deleted = 0;
+				free(old_prop->srcpos);
+				old_prop->srcpos = new_prop->srcpos;
 				free(new_prop);
 				new_prop = NULL;
 				break;
@@ -223,6 +216,8 @@
 			add_child(old_node, new_child);
 	}
 
+	old_node->srcpos = srcpos_extend(old_node->srcpos, new_node->srcpos);
+
 	/* The new node contents are now merged into the old node.  Free
 	 * the new node. */
 	free(new_node);
@@ -239,20 +234,21 @@
 	char *name;
 
 	if (ref[0] == '/') {
+		d = data_add_marker(d, TYPE_STRING, ref);
 		d = data_append_data(d, ref, strlen(ref) + 1);
 
-		p = build_property("target-path", d);
+		p = build_property("target-path", d, NULL);
 	} else {
 		d = data_add_marker(d, REF_PHANDLE, ref);
 		d = data_append_integer(d, 0xffffffff, 32);
 
-		p = build_property("target", d);
+		p = build_property("target", d, NULL);
 	}
 
 	xasprintf(&name, "fragment@%u",
 			next_orphan_fragment++);
 	name_node(new_node, "__overlay__");
-	node = build_node(p, new_node);
+	node = build_node(p, new_node, NULL);
 	name_node(node, name);
 
 	add_child(dt, node);
@@ -340,18 +336,21 @@
 }
 
 void append_to_property(struct node *node,
-				    char *name, const void *data, int len)
+			char *name, const void *data, int len,
+			enum markertype type)
 {
 	struct data d;
 	struct property *p;
 
 	p = get_property(node, name);
 	if (p) {
-		d = data_append_data(p->val, data, len);
+		d = data_add_marker(p->val, type, name);
+		d = data_append_data(d, data, len);
 		p->val = d;
 	} else {
-		d = data_append_data(empty_data, data, len);
-		p = build_property(name, d);
+		d = data_add_marker(empty_data, type, name);
+		d = data_append_data(d, data, len);
+		p = build_property(name, d, NULL);
 		add_property(node, p);
 	}
 }
@@ -594,6 +593,7 @@
 cell_t get_node_phandle(struct node *root, struct node *node)
 {
 	static cell_t phandle = 1; /* FIXME: ick, static local */
+	struct data d = empty_data;
 
 	if ((node->phandle != 0) && (node->phandle != -1))
 		return node->phandle;
@@ -603,17 +603,16 @@
 
 	node->phandle = phandle;
 
+	d = data_add_marker(d, TYPE_UINT32, NULL);
+	d = data_append_cell(d, phandle);
+
 	if (!get_property(node, "linux,phandle")
 	    && (phandle_format & PHANDLE_LEGACY))
-		add_property(node,
-			     build_property("linux,phandle",
-					    data_append_cell(empty_data, phandle)));
+		add_property(node, build_property("linux,phandle", d, NULL));
 
 	if (!get_property(node, "phandle")
 	    && (phandle_format & PHANDLE_EPAPR))
-		add_property(node,
-			     build_property("phandle",
-					    data_append_cell(empty_data, phandle)));
+		add_property(node, build_property("phandle", d, NULL));
 
 	/* If the node *does* have a phandle property, we must
 	 * be dealing with a self-referencing phandle, which will be
@@ -787,7 +786,7 @@
 {
 	struct node *node;
 
-	node = build_node(NULL, NULL);
+	node = build_node(NULL, NULL, NULL);
 	name_node(node, xstrdup(name));
 	add_child(parent, node);
 
@@ -848,8 +847,9 @@
 
 			/* insert it */
 			p = build_property(l->label,
-				data_copy_mem(node->fullpath,
-						strlen(node->fullpath) + 1));
+				data_copy_escape_string(node->fullpath,
+						strlen(node->fullpath)),
+				NULL);
 			add_property(an, p);
 		}
 
@@ -899,7 +899,7 @@
 
 	xasprintf(&entry, "%s:%s:%u",
 			node->fullpath, prop->name, m->offset);
-	append_to_property(fn, m->ref, entry, strlen(entry) + 1);
+	append_to_property(fn, m->ref, entry, strlen(entry) + 1, TYPE_STRING);
 
 	free(entry);
 }
@@ -959,7 +959,7 @@
 	char **compp;
 	int i, depth;
 
-	/* walk back retreiving depth */
+	/* walk back retrieving depth */
 	depth = 0;
 	for (wn = node; wn; wn = wn->parent)
 		depth++;
@@ -982,7 +982,7 @@
 	free(compp);
 
 	value_32 = cpu_to_fdt32(m->offset);
-	append_to_property(wn, prop->name, &value_32, sizeof(value_32));
+	append_to_property(wn, prop->name, &value_32, sizeof(value_32), TYPE_UINT32);
 }
 
 static void generate_local_fixups_tree_internal(struct dt_info *dti,
diff --git a/scripts/dtc/srcpos.c b/scripts/dtc/srcpos.c
index cb6ed0e..f5205fb 100644
--- a/scripts/dtc/srcpos.c
+++ b/scripts/dtc/srcpos.c
@@ -1,20 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright 2007 Jon Loeliger, Freescale Semiconductor, Inc.
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 
 #define _GNU_SOURCE
@@ -33,6 +19,9 @@
 /* This is the list of directories that we search for source files */
 static struct search_path *search_path_head, **search_path_tail;
 
+/* Detect infinite include recursion. */
+#define MAX_SRCFILE_DEPTH     (100)
+static int srcfile_depth; /* = 0 */
 
 static char *get_dirname(const char *path)
 {
@@ -51,11 +40,51 @@
 
 FILE *depfile; /* = NULL */
 struct srcfile_state *current_srcfile; /* = NULL */
+static char *initial_path; /* = NULL */
+static int initial_pathlen; /* = 0 */
+static bool initial_cpp = true;
 
-/* Detect infinite include recursion. */
-#define MAX_SRCFILE_DEPTH     (100)
-static int srcfile_depth; /* = 0 */
+static void set_initial_path(char *fname)
+{
+	int i, len = strlen(fname);
 
+	xasprintf(&initial_path, "%s", fname);
+	initial_pathlen = 0;
+	for (i = 0; i != len; i++)
+		if (initial_path[i] == '/')
+			initial_pathlen++;
+}
+
+static char *shorten_to_initial_path(char *fname)
+{
+	char *p1, *p2, *prevslash1 = NULL;
+	int slashes = 0;
+
+	for (p1 = fname, p2 = initial_path; *p1 && *p2; p1++, p2++) {
+		if (*p1 != *p2)
+			break;
+		if (*p1 == '/') {
+			prevslash1 = p1;
+			slashes++;
+		}
+	}
+	p1 = prevslash1 + 1;
+	if (prevslash1) {
+		int diff = initial_pathlen - slashes, i, j;
+		int restlen = strlen(fname) - (p1 - fname);
+		char *res;
+
+		res = xmalloc((3 * diff) + restlen + 1);
+		for (i = 0, j = 0; i != diff; i++) {
+			res[j++] = '.';
+			res[j++] = '.';
+			res[j++] = '/';
+		}
+		strcpy(res + j, p1);
+		return res;
+	}
+	return NULL;
+}
 
 /**
  * Try to open a file in a given directory.
@@ -157,6 +186,9 @@
 	srcfile->colno = 1;
 
 	current_srcfile = srcfile;
+
+	if (srcfile_depth == 1)
+		set_initial_path(srcfile->name);
 }
 
 bool srcfile_pop(void)
@@ -197,18 +229,6 @@
 	search_path_tail = &node->next;
 }
 
-/*
- * The empty source position.
- */
-
-struct srcpos srcpos_empty = {
-	.first_line = 0,
-	.first_column = 0,
-	.last_line = 0,
-	.last_column = 0,
-	.file = NULL,
-};
-
 void srcpos_update(struct srcpos *pos, const char *text, int len)
 {
 	int i;
@@ -234,13 +254,35 @@
 srcpos_copy(struct srcpos *pos)
 {
 	struct srcpos *pos_new;
+	struct srcfile_state *srcfile_state;
+
+	if (!pos)
+		return NULL;
 
 	pos_new = xmalloc(sizeof(struct srcpos));
+	assert(pos->next == NULL);
 	memcpy(pos_new, pos, sizeof(struct srcpos));
 
+	/* allocate without free */
+	srcfile_state = xmalloc(sizeof(struct srcfile_state));
+	memcpy(srcfile_state, pos->file, sizeof(struct srcfile_state));
+	pos_new->file = srcfile_state;
+
 	return pos_new;
 }
 
+struct srcpos *srcpos_extend(struct srcpos *pos, struct srcpos *newtail)
+{
+	struct srcpos *p;
+
+	if (!pos)
+		return newtail;
+
+	for (p = pos; p->next != NULL; p = p->next);
+	p->next = newtail;
+	return pos;
+}
+
 char *
 srcpos_string(struct srcpos *pos)
 {
@@ -266,6 +308,68 @@
 	return pos_str;
 }
 
+static char *
+srcpos_string_comment(struct srcpos *pos, bool first_line, int level)
+{
+	char *pos_str, *fname, *first, *rest;
+	bool fresh_fname = false;
+
+	if (!pos) {
+		if (level > 1) {
+			xasprintf(&pos_str, "<no-file>:<no-line>");
+			return pos_str;
+		} else {
+			return NULL;
+		}
+	}
+
+	if (!pos->file)
+		fname = "<no-file>";
+	else if (!pos->file->name)
+		fname = "<no-filename>";
+	else if (level > 1)
+		fname = pos->file->name;
+	else {
+		fname = shorten_to_initial_path(pos->file->name);
+		if (fname)
+			fresh_fname = true;
+		else
+			fname = pos->file->name;
+	}
+
+	if (level > 1)
+		xasprintf(&first, "%s:%d:%d-%d:%d", fname,
+			  pos->first_line, pos->first_column,
+			  pos->last_line, pos->last_column);
+	else
+		xasprintf(&first, "%s:%d", fname,
+			  first_line ? pos->first_line : pos->last_line);
+
+	if (fresh_fname)
+		free(fname);
+
+	if (pos->next != NULL) {
+		rest = srcpos_string_comment(pos->next, first_line, level);
+		xasprintf(&pos_str, "%s, %s", first, rest);
+		free(first);
+		free(rest);
+	} else {
+		pos_str = first;
+	}
+
+	return pos_str;
+}
+
+char *srcpos_string_first(struct srcpos *pos, int level)
+{
+	return srcpos_string_comment(pos, true, level);
+}
+
+char *srcpos_string_last(struct srcpos *pos, int level)
+{
+	return srcpos_string_comment(pos, false, level);
+}
+
 void srcpos_verror(struct srcpos *pos, const char *prefix,
 		   const char *fmt, va_list va)
 {
@@ -294,4 +398,9 @@
 {
 	current_srcfile->name = f;
 	current_srcfile->lineno = l;
+
+	if (initial_cpp) {
+		initial_cpp = false;
+		set_initial_path(f);
+	}
 }
diff --git a/scripts/dtc/srcpos.h b/scripts/dtc/srcpos.h
index 9ded12a..4318d7a 100644
--- a/scripts/dtc/srcpos.h
+++ b/scripts/dtc/srcpos.h
@@ -1,20 +1,6 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 /*
  * Copyright 2007 Jon Loeliger, Freescale Semiconductor, Inc.
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 
 #ifndef SRCPOS_H
@@ -74,6 +60,7 @@
     int last_line;
     int last_column;
     struct srcfile_state *file;
+    struct srcpos *next;
 };
 
 #define YYLTYPE struct srcpos
@@ -93,19 +80,18 @@
 				YYRHSLOC(Rhs, 0).last_column;			\
 			(Current).file = YYRHSLOC (Rhs, 0).file;		\
 		}								\
+		(Current).next = NULL;						\
 	} while (0)
 
 
-/*
- * Fictional source position used for IR nodes that are
- * created without otherwise knowing a true source position.
- * For example,constant definitions from the command line.
- */
-extern struct srcpos srcpos_empty;
-
 extern void srcpos_update(struct srcpos *pos, const char *text, int len);
 extern struct srcpos *srcpos_copy(struct srcpos *pos);
+extern struct srcpos *srcpos_extend(struct srcpos *new_srcpos,
+				    struct srcpos *old_srcpos);
 extern char *srcpos_string(struct srcpos *pos);
+extern char *srcpos_string_first(struct srcpos *pos, int level);
+extern char *srcpos_string_last(struct srcpos *pos, int level);
+
 
 extern void PRINTF(3, 0) srcpos_verror(struct srcpos *pos, const char *prefix,
 					const char *fmt, va_list va);
diff --git a/scripts/dtc/treesource.c b/scripts/dtc/treesource.c
index 2461a3d..c9d980c 100644
--- a/scripts/dtc/treesource.c
+++ b/scripts/dtc/treesource.c
@@ -1,21 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
- *
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 
 #include "dtc.h"
@@ -61,24 +46,18 @@
 		|| strchr("\a\b\t\n\v\f\r", c));
 }
 
-static void write_propval_string(FILE *f, struct data val)
+static void write_propval_string(FILE *f, const char *s, size_t len)
 {
-	const char *str = val.val;
-	int i;
-	struct marker *m = val.markers;
+	const char *end = s + len - 1;
 
-	assert(str[val.len-1] == '\0');
+	if (!len)
+		return;
 
-	while (m && (m->offset == 0)) {
-		if (m->type == LABEL)
-			fprintf(f, "%s: ", m->ref);
-		m = m->next;
-	}
+	assert(*end == '\0');
+
 	fprintf(f, "\"");
-
-	for (i = 0; i < (val.len-1); i++) {
-		char c = str[i];
-
+	while (s < end) {
+		char c = *s++;
 		switch (c) {
 		case '\a':
 			fprintf(f, "\\a");
@@ -108,91 +87,80 @@
 			fprintf(f, "\\\"");
 			break;
 		case '\0':
-			fprintf(f, "\", ");
-			while (m && (m->offset <= (i + 1))) {
-				if (m->type == LABEL) {
-					assert(m->offset == (i+1));
-					fprintf(f, "%s: ", m->ref);
-				}
-				m = m->next;
-			}
-			fprintf(f, "\"");
+			fprintf(f, "\\0");
 			break;
 		default:
 			if (isprint((unsigned char)c))
 				fprintf(f, "%c", c);
 			else
-				fprintf(f, "\\x%02hhx", c);
+				fprintf(f, "\\x%02"PRIx8, c);
 		}
 	}
 	fprintf(f, "\"");
-
-	/* Wrap up any labels at the end of the value */
-	for_each_marker_of_type(m, LABEL) {
-		assert (m->offset == val.len);
-		fprintf(f, " %s:", m->ref);
-	}
 }
 
-static void write_propval_cells(FILE *f, struct data val)
+static void write_propval_int(FILE *f, const char *p, size_t len, size_t width)
 {
-	void *propend = val.val + val.len;
-	fdt32_t *cp = (fdt32_t *)val.val;
-	struct marker *m = val.markers;
+	const char *end = p + len;
+	assert(len % width == 0);
 
-	fprintf(f, "<");
-	for (;;) {
-		while (m && (m->offset <= ((char *)cp - val.val))) {
-			if (m->type == LABEL) {
-				assert(m->offset == ((char *)cp - val.val));
-				fprintf(f, "%s: ", m->ref);
-			}
-			m = m->next;
-		}
-
-		fprintf(f, "0x%x", fdt32_to_cpu(*cp++));
-		if ((void *)cp >= propend)
+	for (; p < end; p += width) {
+		switch (width) {
+		case 1:
+			fprintf(f, "%02"PRIx8, *(const uint8_t*)p);
 			break;
-		fprintf(f, " ");
+		case 2:
+			fprintf(f, "0x%02"PRIx16, fdt16_to_cpu(*(const fdt16_t*)p));
+			break;
+		case 4:
+			fprintf(f, "0x%02"PRIx32, fdt32_to_cpu(*(const fdt32_t*)p));
+			break;
+		case 8:
+			fprintf(f, "0x%02"PRIx64, fdt64_to_cpu(*(const fdt64_t*)p));
+			break;
+		}
+		if (p + width < end)
+			fputc(' ', f);
 	}
-
-	/* Wrap up any labels at the end of the value */
-	for_each_marker_of_type(m, LABEL) {
-		assert (m->offset == val.len);
-		fprintf(f, " %s:", m->ref);
-	}
-	fprintf(f, ">");
 }
 
-static void write_propval_bytes(FILE *f, struct data val)
+static bool has_data_type_information(struct marker *m)
 {
-	void *propend = val.val + val.len;
-	const char *bp = val.val;
-	struct marker *m = val.markers;
-
-	fprintf(f, "[");
-	for (;;) {
-		while (m && (m->offset == (bp-val.val))) {
-			if (m->type == LABEL)
-				fprintf(f, "%s: ", m->ref);
-			m = m->next;
-		}
-
-		fprintf(f, "%02hhx", (unsigned char)(*bp++));
-		if ((const void *)bp >= propend)
-			break;
-		fprintf(f, " ");
-	}
-
-	/* Wrap up any labels at the end of the value */
-	for_each_marker_of_type(m, LABEL) {
-		assert (m->offset == val.len);
-		fprintf(f, " %s:", m->ref);
-	}
-	fprintf(f, "]");
+	return m->type >= TYPE_UINT8;
 }
 
-static void write_propval(FILE *f, struct property *prop)
+static struct marker *next_type_marker(struct marker *m)
+{
+	while (m && !has_data_type_information(m))
+		m = m->next;
+	return m;
+}
+
+size_t type_marker_length(struct marker *m)
+{
+	struct marker *next = next_type_marker(m->next);
+
+	if (next)
+		return next->offset - m->offset;
+	return 0;
+}
+
+static const char *delim_start[] = {
+	[TYPE_UINT8] = "[",
+	[TYPE_UINT16] = "/bits/ 16 <",
+	[TYPE_UINT32] = "<",
+	[TYPE_UINT64] = "/bits/ 64 <",
+	[TYPE_STRING] = "",
+};
+static const char *delim_end[] = {
+	[TYPE_UINT8] = "]",
+	[TYPE_UINT16] = ">",
+	[TYPE_UINT32] = ">",
+	[TYPE_UINT64] = ">",
+	[TYPE_STRING] = "",
+};
+
+static enum markertype guess_value_type(struct property *prop)
 {
 	int len = prop->val.len;
 	const char *p = prop->val.val;
@@ -201,11 +169,6 @@
 	int nnotstringlbl = 0, nnotcelllbl = 0;
 	int i;
 
-	if (len == 0) {
-		fprintf(f, ";\n");
-		return;
-	}
-
 	for (i = 0; i < len; i++) {
 		if (! isstring(p[i]))
 			nnotstring++;
@@ -220,17 +183,99 @@
 			nnotcelllbl++;
 	}
 
-	fprintf(f, " = ");
 	if ((p[len-1] == '\0') && (nnotstring == 0) && (nnul < (len-nnul))
 	    && (nnotstringlbl == 0)) {
-		write_propval_string(f, prop->val);
+		return TYPE_STRING;
 	} else if (((len % sizeof(cell_t)) == 0) && (nnotcelllbl == 0)) {
-		write_propval_cells(f, prop->val);
-	} else {
-		write_propval_bytes(f, prop->val);
+		return TYPE_UINT32;
 	}
 
-	fprintf(f, ";\n");
+	return TYPE_UINT8;
+}
+
+static void write_propval(FILE *f, struct property *prop)
+{
+	size_t len = prop->val.len;
+	struct marker *m = prop->val.markers;
+	struct marker dummy_marker;
+	enum markertype emit_type = TYPE_NONE;
+	char *srcstr;
+
+	if (len == 0) {
+		fprintf(f, ";");
+		if (annotate) {
+			srcstr = srcpos_string_first(prop->srcpos, annotate);
+			if (srcstr) {
+				fprintf(f, " /* %s */", srcstr);
+				free(srcstr);
+			}
+		}
+		fprintf(f, "\n");
+		return;
+	}
+
+	fprintf(f, " =");
+
+	if (!next_type_marker(m)) {
+		/* data type information missing, need to guess */
+		dummy_marker.type = guess_value_type(prop);
+		dummy_marker.next = prop->val.markers;
+		dummy_marker.offset = 0;
+		dummy_marker.ref = NULL;
+		m = &dummy_marker;
+	}
+
+	for_each_marker(m) {
+		size_t chunk_len = (m->next ? m->next->offset : len) - m->offset;
+		size_t data_len = type_marker_length(m) ? : len - m->offset;
+		const char *p = &prop->val.val[m->offset];
+
+		if (has_data_type_information(m)) {
+			emit_type = m->type;
+			fprintf(f, " %s", delim_start[emit_type]);
+		} else if (m->type == LABEL)
+			fprintf(f, " %s:", m->ref);
+		else if (m->offset)
+			fputc(' ', f);
+
+		if (emit_type == TYPE_NONE) {
+			assert(chunk_len == 0);
+			continue;
+		}
+
+		switch(emit_type) {
+		case TYPE_UINT16:
+			write_propval_int(f, p, chunk_len, 2);
+			break;
+		case TYPE_UINT32:
+			write_propval_int(f, p, chunk_len, 4);
+			break;
+		case TYPE_UINT64:
+			write_propval_int(f, p, chunk_len, 8);
+			break;
+		case TYPE_STRING:
+			write_propval_string(f, p, chunk_len);
+			break;
+		default:
+			write_propval_int(f, p, chunk_len, 1);
+		}
+
+		if (chunk_len == data_len) {
+			size_t pos = m->offset + chunk_len;
+			fprintf(f, pos == len ? "%s" : "%s,",
+			        delim_end[emit_type] ? : "");
+			emit_type = TYPE_NONE;
+		}
+	}
+	fprintf(f, ";");
+	if (annotate) {
+		srcstr = srcpos_string_first(prop->srcpos, annotate);
+		if (srcstr) {
+			fprintf(f, " /* %s */", srcstr);
+			free(srcstr);
+		}
+	}
+	fprintf(f, "\n");
 }
 
 static void write_tree_source_node(FILE *f, struct node *tree, int level)
@@ -238,14 +283,24 @@
 	struct property *prop;
 	struct node *child;
 	struct label *l;
+	char *srcstr;
 
 	write_prefix(f, level);
 	for_each_label(tree->labels, l)
 		fprintf(f, "%s: ", l->label);
 	if (tree->name && (*tree->name))
-		fprintf(f, "%s {\n", tree->name);
+		fprintf(f, "%s {", tree->name);
 	else
-		fprintf(f, "/ {\n");
+		fprintf(f, "/ {");
+
+	if (annotate) {
+		srcstr = srcpos_string_first(tree->srcpos, annotate);
+		if (srcstr) {
+			fprintf(f, " /* %s */", srcstr);
+			free(srcstr);
+		}
+	}
+	fprintf(f, "\n");
 
 	for_each_property(tree, prop) {
 		write_prefix(f, level+1);
@@ -259,10 +314,17 @@
 		write_tree_source_node(f, child, level+1);
 	}
 	write_prefix(f, level);
-	fprintf(f, "};\n");
+	fprintf(f, "};");
+	if (annotate) {
+		srcstr = srcpos_string_last(tree->srcpos, annotate);
+		if (srcstr) {
+			fprintf(f, " /* %s */", srcstr);
+			free(srcstr);
+		}
+	}
+	fprintf(f, "\n");
 }
 
-
 void dt_to_source(FILE *f, struct dt_info *dti)
 {
 	struct reserve_info *re;
@@ -281,4 +343,3 @@
 
 	write_tree_source_node(f, dti->dt, 0);
 }
-
diff --git a/scripts/dtc/update-dtc-source.sh b/scripts/dtc/update-dtc-source.sh
index 1a009fd..7dd29a0 100755
--- a/scripts/dtc/update-dtc-source.sh
+++ b/scripts/dtc/update-dtc-source.sh
@@ -32,7 +32,7 @@
 DTC_LINUX_PATH=`pwd`/scripts/dtc
 
 DTC_SOURCE="checks.c data.c dtc.c dtc.h flattree.c fstree.c livetree.c srcpos.c \
-		srcpos.h treesource.c util.c util.h version_gen.h Makefile.dtc \
+		srcpos.h treesource.c util.c util.h version_gen.h yamltree.c Makefile.dtc \
 		dtc-lexer.l dtc-parser.y"
 LIBFDT_SOURCE="Makefile.libfdt fdt.c fdt.h fdt_addresses.c fdt_empty_tree.c \
 		fdt_overlay.c fdt_ro.c fdt_rw.c fdt_strerror.c fdt_sw.c \
diff --git a/scripts/dtc/util.c b/scripts/dtc/util.c
index 9953c32..48af961 100644
--- a/scripts/dtc/util.c
+++ b/scripts/dtc/util.c
@@ -1,24 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright 2011 The Chromium Authors, All Rights Reserved.
  * Copyright 2008 Jon Loeliger, Freescale Semiconductor, Inc.
  *
  * util_is_printable_string contributed by
  *	Pantelis Antoniou <pantelis.antoniou AT gmail.com>
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 
 #include <ctype.h>
@@ -46,36 +32,54 @@
 	return d;
 }
 
-/* based in part from (3) vsnprintf */
-int xasprintf(char **strp, const char *fmt, ...)
+int xavsprintf_append(char **strp, const char *fmt, va_list ap)
 {
-	int n, size = 128;	/* start with 128 bytes */
+	int n, size = 0;	/* start with 128 bytes */
 	char *p;
-	va_list ap;
+	va_list ap_copy;
 
-	/* initial pointer is NULL making the fist realloc to be malloc */
-	p = NULL;
-	while (1) {
-		p = xrealloc(p, size);
+	p = *strp;
+	if (p)
+		size = strlen(p);
 
-		/* Try to print in the allocated space. */
-		va_start(ap, fmt);
-		n = vsnprintf(p, size, fmt, ap);
-		va_end(ap);
+	va_copy(ap_copy, ap);
+	n = vsnprintf(NULL, 0, fmt, ap_copy) + 1;
+	va_end(ap_copy);
 
-		/* If that worked, return the string. */
-		if (n > -1 && n < size)
-			break;
-		/* Else try again with more space. */
-		if (n > -1)	/* glibc 2.1 */
-			size = n + 1; /* precisely what is needed */
-		else		/* glibc 2.0 */
-			size *= 2; /* twice the old size */
-	}
+	p = xrealloc(p, size + n);
+
+	n = vsnprintf(p + size, n, fmt, ap);
+
 	*strp = p;
 	return strlen(p);
 }
 
+int xasprintf_append(char **strp, const char *fmt, ...)
+{
+	int n;
+	va_list ap;
+
+	va_start(ap, fmt);
+	n = xavsprintf_append(strp, fmt, ap);
+	va_end(ap);
+
+	return n;
+}
+
+int xasprintf(char **strp, const char *fmt, ...)
+{
+	int n;
+	va_list ap;
+
+	*strp = NULL;
+
+	va_start(ap, fmt);
+	n = xavsprintf_append(strp, fmt, ap);
+	va_end(ap);
+
+	return n;
+}
+
 char *join_path(const char *path, const char *name)
 {
 	int lenp = strlen(path);
@@ -227,11 +231,11 @@
 	return val;
 }
 
-int utilfdt_read_err_len(const char *filename, char **buffp, off_t *len)
+int utilfdt_read_err(const char *filename, char **buffp, size_t *len)
 {
 	int fd = 0;	/* assume stdin */
 	char *buf = NULL;
-	off_t bufsize = 1024, offset = 0;
+	size_t bufsize = 1024, offset = 0;
 	int ret = 0;
 
 	*buffp = NULL;
@@ -264,20 +268,15 @@
 		free(buf);
 	else
 		*buffp = buf;
-	*len = bufsize;
+	if (len)
+		*len = bufsize;
 	return ret;
 }
 
-int utilfdt_read_err(const char *filename, char **buffp)
-{
-	off_t len;
-	return utilfdt_read_err_len(filename, buffp, &len);
-}
-
-char *utilfdt_read_len(const char *filename, off_t *len)
+char *utilfdt_read(const char *filename, size_t *len)
 {
 	char *buff;
-	int ret = utilfdt_read_err_len(filename, &buff, len);
+	int ret = utilfdt_read_err(filename, &buff, len);
 
 	if (ret) {
 		fprintf(stderr, "Couldn't open blob from '%s': %s\n", filename,
@@ -288,12 +287,6 @@
 	return buff;
 }
 
-char *utilfdt_read(const char *filename)
-{
-	off_t len;
-	return utilfdt_read_len(filename, &len);
-}
-
 int utilfdt_write_err(const char *filename, const void *blob)
 {
 	int fd = 1;	/* assume stdout */
diff --git a/scripts/dtc/util.h b/scripts/dtc/util.h
index 66fba8e..ca5cb52 100644
--- a/scripts/dtc/util.h
+++ b/scripts/dtc/util.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 #ifndef UTIL_H
 #define UTIL_H
 
@@ -8,21 +9,6 @@
 /*
  * Copyright 2011 The Chromium Authors, All Rights Reserved.
  * Copyright 2008 Jon Loeliger, Freescale Semiconductor, Inc.
- *
- * This program 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 program 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 program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
- *                                                                   USA
  */
 
 #ifdef __GNUC__
@@ -72,6 +58,8 @@
 extern char *xstrdup(const char *s);
 
 extern int PRINTF(2, 3) xasprintf(char **strp, const char *fmt, ...);
+extern int PRINTF(2, 3) xasprintf_append(char **strp, const char *fmt, ...);
+extern int xavsprintf_append(char **strp, const char *fmt, va_list ap);
 extern char *join_path(const char *path, const char *name);
 
 /**
@@ -98,16 +86,10 @@
  * stderr.
  *
  * @param filename	The filename to read, or - for stdin
+ * @param len		If non-NULL, the amount of data we managed to read
  * @return Pointer to allocated buffer containing fdt, or NULL on error
  */
-char *utilfdt_read(const char *filename);
-
-/**
- * Like utilfdt_read(), but also passes back the size of the file read.
- *
- * @param len		If non-NULL, the amount of data we managed to read
- */
-char *utilfdt_read_len(const char *filename, off_t *len);
+char *utilfdt_read(const char *filename, size_t *len);
 
 /**
  * Read a device tree file into a buffer. Does not report errors, but only
@@ -116,23 +98,17 @@
  *
  * @param filename	The filename to read, or - for stdin
  * @param buffp		Returns pointer to buffer containing fdt
+ * @param len		If non-NULL, the amount of data we managed to read
  * @return 0 if ok, else an errno value representing the error
  */
-int utilfdt_read_err(const char *filename, char **buffp);
-
-/**
- * Like utilfdt_read_err(), but also passes back the size of the file read.
- *
- * @param len		If non-NULL, the amount of data we managed to read
- */
-int utilfdt_read_err_len(const char *filename, char **buffp, off_t *len);
+int utilfdt_read_err(const char *filename, char **buffp, size_t *len);
 
 /**
  * Write a device tree buffer to a file. This will report any errors on
  * stderr.
  *
  * @param filename	The filename to write, or - for stdout
- * @param blob		Poiner to buffer containing fdt
+ * @param blob		Pointer to buffer containing fdt
  * @return 0 if ok, -1 on error
  */
 int utilfdt_write(const char *filename, const void *blob);
@@ -143,7 +119,7 @@
  * an error message for the user.
  *
  * @param filename	The filename to write, or - for stdout
- * @param blob		Poiner to buffer containing fdt
+ * @param blob		Pointer to buffer containing fdt
  * @return 0 if ok, else an errno value representing the error
  */
 int utilfdt_write_err(const char *filename, const void *blob);
diff --git a/scripts/dtc/version_gen.h b/scripts/dtc/version_gen.h
index b00f14f..f2761e2 100644
--- a/scripts/dtc/version_gen.h
+++ b/scripts/dtc/version_gen.h
@@ -1 +1 @@
-#define DTC_VERSION "DTC 1.4.6-g84e414b0"
+#define DTC_VERSION "DTC 1.5.0-g702c1b6c"
diff --git a/scripts/dtc/yamltree.c b/scripts/dtc/yamltree.c
new file mode 100644
index 0000000..5b6ea8e
--- /dev/null
+++ b/scripts/dtc/yamltree.c
@@ -0,0 +1,233 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * (C) Copyright Linaro, Ltd. 2018
+ * (C) Copyright Arm Holdings.  2017
+ * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
+ */
+
+#include <stdlib.h>
+#include <yaml.h>
+#include "dtc.h"
+#include "srcpos.h"
+
+char *yaml_error_name[] = {
+	[YAML_NO_ERROR] = "no error",
+	[YAML_MEMORY_ERROR] = "memory error",
+	[YAML_READER_ERROR] = "reader error",
+	[YAML_SCANNER_ERROR] = "scanner error",
+	[YAML_PARSER_ERROR] = "parser error",
+	[YAML_COMPOSER_ERROR] = "composer error",
+	[YAML_WRITER_ERROR] = "writer error",
+	[YAML_EMITTER_ERROR] = "emitter error",
+};
+
+#define yaml_emitter_emit_or_die(emitter, event) (			\
+{									\
+	if (!yaml_emitter_emit(emitter, event))				\
+		die("yaml '%s': %s in %s, line %i\n",			\
+		    yaml_error_name[(emitter)->error], 			\
+		    (emitter)->problem, __func__, __LINE__);		\
+})
+
+static void yaml_propval_int(yaml_emitter_t *emitter, struct marker *markers, char *data, int len, int width)
+{
+	yaml_event_t event;
+	void *tag;
+	int off, start_offset = markers->offset;
+
+	switch(width) {
+		case 1: tag = "!u8"; break;
+		case 2: tag = "!u16"; break;
+		case 4: tag = "!u32"; break;
+		case 8: tag = "!u64"; break;
+		default:
+			die("Invalid width %i", width);
+	}
+	assert(len % width == 0);
+
+	yaml_sequence_start_event_initialize(&event, NULL,
+		(yaml_char_t *)tag, width == 4, YAML_FLOW_SEQUENCE_STYLE);
+	yaml_emitter_emit_or_die(emitter, &event);
+
+	for (off = 0; off < len; off += width) {
+		char buf[32];
+		struct marker *m;
+		bool is_phandle = false;
+
+		switch(width) {
+		case 1:
+			sprintf(buf, "0x%"PRIx8, *(uint8_t*)(data + off));
+			break;
+		case 2:
+			sprintf(buf, "0x%"PRIx16, fdt16_to_cpu(*(fdt16_t*)(data + off)));
+			break;
+		case 4:
+			sprintf(buf, "0x%"PRIx32, fdt32_to_cpu(*(fdt32_t*)(data + off)));
+			m = markers;
+			is_phandle = false;
+			for_each_marker_of_type(m, REF_PHANDLE) {
+				if (m->offset == (start_offset + off)) {
+					is_phandle = true;
+					break;
+				}
+			}
+			break;
+		case 8:
+			sprintf(buf, "0x%"PRIx64, fdt64_to_cpu(*(fdt64_t*)(data + off)));
+			break;
+		}
+
+		if (is_phandle)
+			yaml_scalar_event_initialize(&event, NULL,
+				(yaml_char_t*)"!phandle", (yaml_char_t *)buf,
+				strlen(buf), 0, 0, YAML_PLAIN_SCALAR_STYLE);
+		else
+			yaml_scalar_event_initialize(&event, NULL,
+				(yaml_char_t*)YAML_INT_TAG, (yaml_char_t *)buf,
+				strlen(buf), 1, 1, YAML_PLAIN_SCALAR_STYLE);
+		yaml_emitter_emit_or_die(emitter, &event);
+	}
+
+	yaml_sequence_end_event_initialize(&event);
+	yaml_emitter_emit_or_die(emitter, &event);
+}
+
+static void yaml_propval_string(yaml_emitter_t *emitter, char *str, int len)
+{
+	yaml_event_t event;
+	int i;
+
+	assert(str[len-1] == '\0');
+
+	/* Make sure the entire string is in the lower 7-bit ascii range */
+	for (i = 0; i < len; i++)
+		assert(isascii(str[i]));
+
+	yaml_scalar_event_initialize(&event, NULL,
+		(yaml_char_t *)YAML_STR_TAG, (yaml_char_t*)str,
+		len-1, 0, 1, YAML_DOUBLE_QUOTED_SCALAR_STYLE);
+	yaml_emitter_emit_or_die(emitter, &event);
+}
+
+static void yaml_propval(yaml_emitter_t *emitter, struct property *prop)
+{
+	yaml_event_t event;
+	int len = prop->val.len;
+	struct marker *m = prop->val.markers;
+
+	/* Emit the property name */
+	yaml_scalar_event_initialize(&event, NULL,
+		(yaml_char_t *)YAML_STR_TAG, (yaml_char_t*)prop->name,
+		strlen(prop->name), 1, 1, YAML_PLAIN_SCALAR_STYLE);
+	yaml_emitter_emit_or_die(emitter, &event);
+
+	/* Boolean properties are easiest to deal with. Length is zero, so just emit 'true' */
+	if (len == 0) {
+		yaml_scalar_event_initialize(&event, NULL,
+			(yaml_char_t *)YAML_BOOL_TAG,
+			(yaml_char_t*)"true",
+			strlen("true"), 1, 0, YAML_PLAIN_SCALAR_STYLE);
+		yaml_emitter_emit_or_die(emitter, &event);
+		return;
+	}
+
+	if (!m)
+		die("No markers present in property '%s' value\n", prop->name);
+
+	yaml_sequence_start_event_initialize(&event, NULL,
+		(yaml_char_t *)YAML_SEQ_TAG, 1, YAML_FLOW_SEQUENCE_STYLE);
+	yaml_emitter_emit_or_die(emitter, &event);
+
+	for_each_marker(m) {
+		int chunk_len;
+		char *data = &prop->val.val[m->offset];
+
+		if (m->type < TYPE_UINT8)
+			continue;
+
+		chunk_len = type_marker_length(m) ? : len;
+		assert(chunk_len > 0);
+		len -= chunk_len;
+
+		switch(m->type) {
+		case TYPE_UINT16:
+			yaml_propval_int(emitter, m, data, chunk_len, 2);
+			break;
+		case TYPE_UINT32:
+			yaml_propval_int(emitter, m, data, chunk_len, 4);
+			break;
+		case TYPE_UINT64:
+			yaml_propval_int(emitter, m, data, chunk_len, 8);
+			break;
+		case TYPE_STRING:
+			yaml_propval_string(emitter, data, chunk_len);
+			break;
+		default:
+			yaml_propval_int(emitter, m, data, chunk_len, 1);
+			break;
+		}
+	}
+
+	yaml_sequence_end_event_initialize(&event);
+	yaml_emitter_emit_or_die(emitter, &event);
+}
+
+
+static void yaml_tree(struct node *tree, yaml_emitter_t *emitter)
+{
+	struct property *prop;
+	struct node *child;
+	yaml_event_t event;
+
+	if (tree->deleted)
+		return;
+
+	yaml_mapping_start_event_initialize(&event, NULL,
+		(yaml_char_t *)YAML_MAP_TAG, 1, YAML_ANY_MAPPING_STYLE);
+	yaml_emitter_emit_or_die(emitter, &event);
+
+	for_each_property(tree, prop)
+		yaml_propval(emitter, prop);
+
+	/* Loop over all the children, emitting them into the map */
+	for_each_child(tree, child) {
+		yaml_scalar_event_initialize(&event, NULL,
+			(yaml_char_t *)YAML_STR_TAG, (yaml_char_t*)child->name,
+			strlen(child->name), 1, 0, YAML_PLAIN_SCALAR_STYLE);
+		yaml_emitter_emit_or_die(emitter, &event);
+		yaml_tree(child, emitter);
+	}
+
+	yaml_mapping_end_event_initialize(&event);
+	yaml_emitter_emit_or_die(emitter, &event);
+}
+
+void dt_to_yaml(FILE *f, struct dt_info *dti)
+{
+	yaml_emitter_t emitter;
+	yaml_event_t event;
+
+	yaml_emitter_initialize(&emitter);
+	yaml_emitter_set_output_file(&emitter, f);
+	yaml_stream_start_event_initialize(&event, YAML_UTF8_ENCODING);
+	yaml_emitter_emit_or_die(&emitter, &event);
+
+	yaml_document_start_event_initialize(&event, NULL, NULL, NULL, 0);
+	yaml_emitter_emit_or_die(&emitter, &event);
+
+	yaml_sequence_start_event_initialize(&event, NULL, (yaml_char_t *)YAML_SEQ_TAG, 1, YAML_ANY_SEQUENCE_STYLE);
+	yaml_emitter_emit_or_die(&emitter, &event);
+
+	yaml_tree(dti->dt, &emitter);
+
+	yaml_sequence_end_event_initialize(&event);
+	yaml_emitter_emit_or_die(&emitter, &event);
+
+	yaml_document_end_event_initialize(&event, 0);
+	yaml_emitter_emit_or_die(&emitter, &event);
+
+	yaml_stream_end_event_initialize(&event);
+	yaml_emitter_emit_or_die(&emitter, &event);
+
+	yaml_emitter_delete(&emitter);
+}