diff --git a/common/cmd_fdt.c b/common/cmd_fdt.c
index 4639126..9cd22ee 100644
--- a/common/cmd_fdt.c
+++ b/common/cmd_fdt.c
@@ -184,23 +184,28 @@
 	} else if (argv[1][0] == 's') {
 		char *pathp;		/* path */
 		char *prop;		/* property */
-		char *newval;		/* value from the user (as a string) */
 		int  nodeoffset;	/* node offset from libfdt */
 		static char data[SCRATCHPAD];	/* storage for the property */
 		int  len;		/* new length of the property */
 		int  ret;		/* return value */
 
 		/*
-		 * Parameters: Node path, property, value.
+		 * Parameters: Node path, property, optional value.
 		 */
-		if (argc < 5) {
+		if (argc < 4) {
 			printf ("Usage:\n%s\n", cmdtp->usage);
 			return 1;
 		}
 
 		pathp  = argv[2];
 		prop   = argv[3];
-		newval = argv[4];
+		if (argc == 4) {
+			len = 0;
+		} else {
+			ret = fdt_parse_prop(pathp, prop, argv[4], data, &len);
+			if (ret != 0)
+				return ret;
+		}
 
 		nodeoffset = fdt_path_offset (fdt, pathp);
 		if (nodeoffset < 0) {
@@ -211,9 +216,6 @@
 				fdt_strerror(nodeoffset));
 			return 1;
 		}
-		ret = fdt_parse_prop(pathp, prop, newval, data, &len);
-		if (ret != 0)
-			return ret;
 
 		ret = fdt_setprop(fdt, nodeoffset, prop, data, len);
 		if (ret < 0) {
@@ -681,7 +683,7 @@
 #ifdef CONFIG_OF_BOARD_SETUP
 	"fdt boardsetup                      - Do board-specific set up\n"
 #endif
-	"fdt move   <fdt> <newaddr> <length> - Copy the fdt to <addr>\n"
+	"fdt move   <fdt> <newaddr> <length> - Copy the fdt to <addr> and make it active\n"
 	"fdt print  <path> [<prop>]          - Recursive print starting at <path>\n"
 	"fdt list   <path> [<prop>]          - Print one level starting at <path>\n"
 	"fdt set    <path> <prop> [<val>]    - Set <property> [to <val>]\n"
@@ -694,10 +696,6 @@
 #ifdef CONFIG_OF_HAS_BD_T
 	"fdt bd_t   - Add/replace the /bd_t branch in the tree\n"
 #endif
-	"Hints:\n"
-	" If the property you are setting/printing has a '#' character or spaces,\n"
-	"     you MUST escape it with a \\ character or quote it with \".\n"
-	"Examples: fdt print /               # print the whole tree\n"
-	"          fdt print /cpus \"#address-cells\"\n"
-	"          fdt set   /cpus \"#address-cells\" \"[00 00 00 01]\"\n"
+	"NOTE: If the path or property you are setting/printing has a '#' character\n"
+	"     or spaces, you MUST escape it with a \\ character or quote it with \".\n"
 );
diff --git a/common/fdt_support.c b/common/fdt_support.c
index b5ee6e9..92f1c7f 100644
--- a/common/fdt_support.c
+++ b/common/fdt_support.c
@@ -111,6 +111,7 @@
 	int   err;
 	u32   tmp;		/* used to set 32 bit integer properties */
 	char  *str;		/* used to set string properties */
+	const char *path;
 
 	err = fdt_check_header(fdt);
 	if (err < 0) {
@@ -148,14 +149,7 @@
 	nodeoffset = fdt_path_offset (fdt, "/chosen");
 
 	/*
-	 * If we have a "chosen" node already the "force the writing"
-	 * is not set, our job is done.
-	 */
-	if ((nodeoffset >= 0) && !force)
-		return 0;
-
-	/*
-	 * No "chosen" node in the blob: create it.
+	 * If there is no "chosen" node in the blob, create it.
 	 */
 	if (nodeoffset < 0) {
 		/*
@@ -170,42 +164,55 @@
 	}
 
 	/*
-	 * Update pre-existing properties, create them if non-existant.
+	 * Create /chosen properites that don't exist in the fdt.
+	 * If the property exists, update it only if the "force" parameter
+	 * is true.
 	 */
 	str = getenv("bootargs");
 	if (str != NULL) {
-		err = fdt_setprop(fdt, nodeoffset,
-			"bootargs", str, strlen(str)+1);
-		if (err < 0)
-			printf("WARNING: could not set bootargs %s.\n",
-				fdt_strerror(err));
+		path = fdt_getprop(fdt, nodeoffset, "bootargs", NULL);
+		if ((path == NULL) || force) {
+			err = fdt_setprop(fdt, nodeoffset,
+				"bootargs", str, strlen(str)+1);
+			if (err < 0)
+				printf("WARNING: could not set bootargs %s.\n",
+					fdt_strerror(err));
+		}
 	}
 	if (initrd_start && initrd_end) {
-		tmp = __cpu_to_be32(initrd_start);
-		err = fdt_setprop(fdt, nodeoffset,
-			 "linux,initrd-start", &tmp, sizeof(tmp));
-		if (err < 0)
-			printf("WARNING: "
-				"could not set linux,initrd-start %s.\n",
-				fdt_strerror(err));
-		tmp = __cpu_to_be32(initrd_end);
-		err = fdt_setprop(fdt, nodeoffset,
-			"linux,initrd-end", &tmp, sizeof(tmp));
-		if (err < 0)
-			printf("WARNING: could not set linux,initrd-end %s.\n",
-				fdt_strerror(err));
+		path = fdt_getprop(fdt, nodeoffset, "linux,initrd-start", NULL);
+		if ((path == NULL) || force) {
+			tmp = __cpu_to_be32(initrd_start);
+			err = fdt_setprop(fdt, nodeoffset,
+				"linux,initrd-start", &tmp, sizeof(tmp));
+			if (err < 0)
+				printf("WARNING: "
+					"could not set linux,initrd-start %s.\n",
+					fdt_strerror(err));
+			tmp = __cpu_to_be32(initrd_end);
+			err = fdt_setprop(fdt, nodeoffset,
+				"linux,initrd-end", &tmp, sizeof(tmp));
+			if (err < 0)
+				printf("WARNING: could not set linux,initrd-end %s.\n",
+					fdt_strerror(err));
+		}
 	}
 
 #ifdef CONFIG_OF_STDOUT_VIA_ALIAS
-	err = fdt_fixup_stdout(fdt, nodeoffset);
+	path = fdt_getprop(fdt, nodeoffset, "linux,stdout-path", NULL);
+	if ((path == NULL) || force)
+		err = fdt_fixup_stdout(fdt, nodeoffset);
 #endif
 
 #ifdef OF_STDOUT_PATH
-	err = fdt_setprop(fdt, nodeoffset,
-		"linux,stdout-path", OF_STDOUT_PATH, strlen(OF_STDOUT_PATH)+1);
-	if (err < 0)
-		printf("WARNING: could not set linux,stdout-path %s.\n",
-			fdt_strerror(err));
+	path = fdt_getprop(fdt, nodeoffset, "linux,stdout-path", NULL);
+	if ((path == NULL) || force) {
+		err = fdt_setprop(fdt, nodeoffset,
+			"linux,stdout-path", OF_STDOUT_PATH, strlen(OF_STDOUT_PATH)+1);
+		if (err < 0)
+			printf("WARNING: could not set linux,stdout-path %s.\n",
+				fdt_strerror(err));
+	}
 #endif
 
 	return err;
diff --git a/include/fdt_support.h b/include/fdt_support.h
index 3d6c1a8..58e26ab 100644
--- a/include/fdt_support.h
+++ b/include/fdt_support.h
@@ -46,6 +46,8 @@
 			    const char *prop, u32 val, int create);
 int fdt_fixup_memory(void *blob, u64 start, u64 size);
 void fdt_fixup_ethernet(void *fdt, bd_t *bd);
+int fdt_find_and_setprop(void *fdt, const char *node, const char *prop,
+			 const void *val, int len, int create);
 
 #ifdef CONFIG_OF_HAS_UBOOT_ENV
 int fdt_env(void *fdt);
diff --git a/include/libfdt.h b/include/libfdt.h
index 8050049..6c05236 100644
--- a/include/libfdt.h
+++ b/include/libfdt.h
@@ -655,8 +655,65 @@
 /* Write-in-place functions                                           */
 /**********************************************************************/
 
+/**
+ * fdt_setprop_inplace - change a property's value, but not its size
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @val: pointer to data to replace the property value with
+ * @len: length of the property value
+ *
+ * fdt_setprop_inplace() replaces the value of a given property with
+ * the data in val, of length len.  This function cannot change the
+ * size of a property, and so will only work if len is equal to the
+ * current length of the property.
+ *
+ * This function will alter only the bytes in the blob which contain
+ * the given property value, and will not alter or move any other part
+ * of the tree.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOSPACE, if len is not equal to the property's current length
+ *	-FDT_ERR_NOTFOUND, node does not have the named property
+ *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
 int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
 			const void *val, int len);
+
+/**
+ * fdt_setprop_inplace_cell - change the value of a single-cell property
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @val: cell (32-bit integer) value to replace the property with
+ *
+ * fdt_setprop_inplace_cell() replaces the value of a given property
+ * with the 32-bit integer cell value in val, converting val to
+ * big-endian if necessary.  This function cannot change the size of a
+ * property, and so will only work if the property already exists and
+ * has length 4.
+ *
+ * This function will alter only the bytes in the blob which contain
+ * the given property value, and will not alter or move any other part
+ * of the tree.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOSPACE, if the property's length is not equal to 4
+  *	-FDT_ERR_NOTFOUND, node does not have the named property
+ *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
 static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
 					   const char *name, uint32_t val)
 {
@@ -664,7 +721,54 @@
 	return fdt_setprop_inplace(fdt, nodeoffset, name, &val, sizeof(val));
 }
 
+/**
+ * fdt_nop_property - replace a property with nop tags
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to nop
+ * @name: name of the property to nop
+ *
+ * fdt_nop_property() will replace a given property's representation
+ * in the blob with FDT_NOP tags, effectively removing it from the
+ * tree.
+ *
+ * This function will alter only the bytes in the blob which contain
+ * the property, and will not alter or move any other part of the
+ * tree.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOTFOUND, node does not have the named property
+ *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
 int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
+
+/**
+ * fdt_nop_node - replace a node (subtree) with nop tags
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node to nop
+ *
+ * fdt_nop_node() will replace a given node's representation in the
+ * blob, including all its subnodes, if any, with FDT_NOP tags,
+ * effectively removing it from the tree.
+ *
+ * This function will alter only the bytes in the blob which contain
+ * the node and its properties and subnodes, and will not alter or
+ * move any other part of the tree.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
 int fdt_nop_node(void *fdt, int nodeoffset);
 
 /**********************************************************************/
@@ -693,23 +797,242 @@
 int fdt_open_into(const void *fdt, void *buf, int bufsize);
 int fdt_pack(void *fdt);
 
+/**
+ * fdt_add_mem_rsv - add one memory reserve map entry
+ * @fdt: pointer to the device tree blob
+ * @addres, @size: 64-bit values (native endian)
+ *
+ * Adds a reserve map entry to the given blob reserving a region at
+ * address address of length size.
+ *
+ * This function will insert data into the reserve map and will
+ * therfore change the indexes of some entries in the table.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
+ *		contain the new reservation entry
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
 int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
+
+/**
+ * fdt_del_mem_rsv - remove a memory reserve map entry
+ * @fdt: pointer to the device tree blob
+ * @n: entry to remove
+ *
+ * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
+ * the blob.
+ *
+ * This function will delete data from the reservation table and will
+ * therfore change the indexes of some entries in the table.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
+ *		are less than n+1 reserve map entries)
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
 int fdt_del_mem_rsv(void *fdt, int n);
 
+/**
+ * fdt_setprop - create or change a property
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @val: pointer to data to set the property value to
+ * @len: length of the property value
+ *
+ * fdt_setprop() sets the value of the named property in the given
+ * node to the given value and length, creeating the property if it
+ * does not already exist.
+ *
+ * This function may insert or delete data from the blob, and will
+ * therefore change the offsets of some existing nodes.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
+ *		contain the new property value
+ *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
 int fdt_setprop(void *fdt, int nodeoffset, const char *name,
 		const void *val, int len);
+
+/**
+ * fdt_setprop_cell - set a property to a single cell value
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @val: 32-bit integer value for the property (native endian)
+ *
+ * fdt_setprop_cell() sets the value of the named property in the
+ * given node to the given cell value (converting to big-endian if
+ * necessary), or creates a new property with that value if it does
+ * not already exist.
+ *
+ * This function may insert or delete data from the blob, and will
+ * therefore change the offsets of some existing nodes.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
+ *		contain the new property value
+ *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
 static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
 				   uint32_t val)
 {
 	val = cpu_to_fdt32(val);
 	return fdt_setprop(fdt, nodeoffset, name, &val, sizeof(val));
 }
+
+/**
+ * fdt_setprop_string - set a property to a string value
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @str: string value for the property
+ *
+ * fdt_setprop_string() sets the value of the named property in the
+ * given node to the given string value (using the length of the
+ * string to determine the new length of the property), or creates a
+ * new property with that value if it does not already exist.
+ *
+ * This function may insert or delete data from the blob, and will
+ * therefore change the offsets of some existing nodes.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
+ *		contain the new property value
+ *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
 #define fdt_setprop_string(fdt, nodeoffset, name, str) \
 	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
+
+/**
+ * fdt_delprop - delete a property
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to nop
+ * @name: name of the property to nop
+ *
+ * fdt_del_property() will delete the given property.
+ *
+ * This function will delete data from the blob, and will therefore
+ * change the offsets of some existing nodes.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_NOTFOUND, node does not have the named property
+ *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
 int fdt_delprop(void *fdt, int nodeoffset, const char *name);
+
+/**
+ * fdt_add_subnode_namelen - creates a new node based on substring
+ * @fdt: pointer to the device tree blob
+ * @parentoffset: structure block offset of a node
+ * @name: name of the subnode to locate
+ * @namelen: number of characters of name to consider
+ *
+ * Identical to fdt_add_subnode(), but use only the first namelen
+ * characters of name as the name of the new node.  This is useful for
+ * creating subnodes based on a portion of a larger string, such as a
+ * full path.
+ */
 int fdt_add_subnode_namelen(void *fdt, int parentoffset,
 			    const char *name, int namelen);
+
+/**
+ * fdt_add_subnode - creates a new node
+ * @fdt: pointer to the device tree blob
+ * @parentoffset: structure block offset of a node
+ * @name: name of the subnode to locate
+ *
+ * fdt_add_subnode() creates a new node as a subnode of the node at
+ * structure block offset parentoffset, with the given name (which
+ * should include the unit address, if any).
+ *
+ * This function will insert data into the blob, and will therefore
+ * change the offsets of some existing nodes.
+
+ * returns:
+ *	structure block offset of the created nodeequested subnode (>=0), on success
+ *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
+ *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
+ *	-FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
+ *		the given name
+ *	-FDT_ERR_NOSPACE, if there is insufficient free space in the
+ *		blob to contain the new node
+ *	-FDT_ERR_NOSPACE
+ *	-FDT_ERR_BADLAYOUT
+ *      -FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_TRUNCATED, standard meanings.
+ */
 int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
+
+/**
+ * fdt_del_node - delete a node (subtree)
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node to nop
+ *
+ * fdt_del_node() will remove the given node, including all its
+ * subnodes if any, from the blob.
+ *
+ * This function will delete data from the blob, and will therefore
+ * change the offsets of some existing nodes.
+ *
+ * returns:
+ *	0, on success
+ *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *	-FDT_ERR_BADLAYOUT,
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE,
+ *	-FDT_ERR_TRUNCATED, standard meanings
+ */
 int fdt_del_node(void *fdt, int nodeoffset);
 
 /**********************************************************************/
diff --git a/libfdt/fdt_rw.c b/libfdt/fdt_rw.c
index dfe5628..6673f8e 100644
--- a/libfdt/fdt_rw.c
+++ b/libfdt/fdt_rw.c
@@ -358,12 +358,12 @@
 	memmove(buf + mem_rsv_off, fdt + fdt_off_mem_rsvmap(fdt), mem_rsv_size);
 	fdt_set_off_mem_rsvmap(buf, mem_rsv_off);
 
-	memcpy(buf + struct_off, fdt + fdt_off_dt_struct(fdt), struct_size);
+	memmove(buf + struct_off, fdt + fdt_off_dt_struct(fdt), struct_size);
 	fdt_set_off_dt_struct(buf, struct_off);
 	fdt_set_size_dt_struct(buf, struct_size);
 
-	memcpy(buf + strings_off, fdt + fdt_off_dt_strings(fdt),
-	       fdt_size_dt_strings(fdt));
+	memmove(buf + strings_off, fdt + fdt_off_dt_strings(fdt),
+		fdt_size_dt_strings(fdt));
 	fdt_set_off_dt_strings(buf, strings_off);
 	fdt_set_size_dt_strings(buf, fdt_size_dt_strings(fdt));
 }