7 files changed, 242 insertions, 42 deletions

diff --git a/scripts/dtc/libfdt/Makefile.libfdt b/scripts/dtc/libfdt/Makefile.libfdt
index 09c322ed82ba..098b3f36e668 100644
--- a/scripts/dtc/libfdt/Makefile.libfdt
+++ b/scripts/dtc/libfdt/Makefile.libfdt
@@ -7,5 +7,5 @@ LIBFDT_soname = libfdt.$(SHAREDLIB_EXT).1
 LIBFDT_INCLUDES = fdt.h libfdt.h libfdt_env.h
 LIBFDT_VERSION = version.lds
 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_addresses.c fdt_overlay.c
 LIBFDT_OBJS = $(LIBFDT_SRCS:%.c=%.o)
diff --git a/scripts/dtc/libfdt/fdt_ro.c b/scripts/dtc/libfdt/fdt_ro.c
index 50cce864283c..3d00d2eee0e3 100644
--- a/scripts/dtc/libfdt/fdt_ro.c
+++ b/scripts/dtc/libfdt/fdt_ro.c
@@ -88,6 +88,32 @@ static int _fdt_string_eq(const void *fdt, int stroffset,
         return (strlen(p) == len) && (memcmp(p, s, len) == 0);
 }
 
+uint32_t fdt_get_max_phandle(const void *fdt)
+{
+        uint32_t max_phandle = 0;
+        int offset;
+
+        for (offset = fdt_next_node(fdt, -1, NULL);;
+             offset = fdt_next_node(fdt, offset, NULL)) {
+                uint32_t phandle;
+
+                if (offset == -FDT_ERR_NOTFOUND)
+                        return max_phandle;
+
+                if (offset < 0)
+                        return (uint32_t)-1;
+
+                phandle = fdt_get_phandle(fdt, offset);
+                if (phandle == (uint32_t)-1)
+                        continue;
+
+                if (phandle > max_phandle)
+                        max_phandle = phandle;
+        }
+
+        return 0;
+}
+
 int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size)
 {
         FDT_CHECK_HEADER(fdt);
@@ -545,7 +571,7 @@ int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property)
 
         list = fdt_getprop(fdt, nodeoffset, property, &length);
         if (!list)
-                return -length;
+                return length;
 
         end = list + length;
 
@@ -571,7 +597,7 @@ int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
 
         list = fdt_getprop(fdt, nodeoffset, property, &length);
         if (!list)
-                return -length;
+                return length;
 
         len = strlen(string) + 1;
         end = list + length;
diff --git a/scripts/dtc/libfdt/fdt_rw.c b/scripts/dtc/libfdt/fdt_rw.c
index 8be02b1f68f3..2eed4f58387c 100644
--- a/scripts/dtc/libfdt/fdt_rw.c
+++ b/scripts/dtc/libfdt/fdt_rw.c
@@ -191,17 +191,13 @@ int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size)
 int fdt_del_mem_rsv(void *fdt, int n)
 {
         struct fdt_reserve_entry *re = _fdt_mem_rsv_w(fdt, n);
-        int err;
 
         FDT_RW_CHECK_HEADER(fdt);
 
         if (n >= fdt_num_mem_rsv(fdt))
                 return -FDT_ERR_NOTFOUND;
 
-        err = _fdt_splice_mem_rsv(fdt, re, 1, 0);
-        if (err)
-                return err;
-        return 0;
+        return _fdt_splice_mem_rsv(fdt, re, 1, 0);
 }
 
 static int _fdt_resize_property(void *fdt, int nodeoffset, const char *name,
diff --git a/scripts/dtc/libfdt/fdt_strerror.c b/scripts/dtc/libfdt/fdt_strerror.c
index e6c3ceee8c58..9677a1887e57 100644
--- a/scripts/dtc/libfdt/fdt_strerror.c
+++ b/scripts/dtc/libfdt/fdt_strerror.c
@@ -69,6 +69,7 @@ static struct fdt_errtabent fdt_errtable[] = {
 
         FDT_ERRTABENT(FDT_ERR_BADOFFSET),
         FDT_ERRTABENT(FDT_ERR_BADPATH),
+        FDT_ERRTABENT(FDT_ERR_BADPHANDLE),
         FDT_ERRTABENT(FDT_ERR_BADSTATE),
 
         FDT_ERRTABENT(FDT_ERR_TRUNCATED),
@@ -76,6 +77,11 @@ static struct fdt_errtabent fdt_errtable[] = {
         FDT_ERRTABENT(FDT_ERR_BADVERSION),
         FDT_ERRTABENT(FDT_ERR_BADSTRUCTURE),
         FDT_ERRTABENT(FDT_ERR_BADLAYOUT),
+        FDT_ERRTABENT(FDT_ERR_INTERNAL),
+        FDT_ERRTABENT(FDT_ERR_BADNCELLS),
+        FDT_ERRTABENT(FDT_ERR_BADVALUE),
+        FDT_ERRTABENT(FDT_ERR_BADOVERLAY),
+        FDT_ERRTABENT(FDT_ERR_NOPHANDLES),
 };
 #define FDT_ERRTABSIZE  (sizeof(fdt_errtable) / sizeof(fdt_errtable[0]))
 
diff --git a/scripts/dtc/libfdt/fdt_wip.c b/scripts/dtc/libfdt/fdt_wip.c
index c5bbb68d3273..6aaab399929c 100644
--- a/scripts/dtc/libfdt/fdt_wip.c
+++ b/scripts/dtc/libfdt/fdt_wip.c
@@ -55,21 +55,42 @@
 
 #include "libfdt_internal.h"
 
+int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
+                                        const char *name, int namelen,
+                                        uint32_t idx, const void *val,
+                                        int len)
+{
+        void *propval;
+        int proplen;
+
+        propval = fdt_getprop_namelen_w(fdt, nodeoffset, name, namelen,
+                                        &proplen);
+        if (!propval)
+                return proplen;
+
+        if (proplen < (len + idx))
+                return -FDT_ERR_NOSPACE;
+
+        memcpy((char *)propval + idx, val, len);
+        return 0;
+}
+
 int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
                         const void *val, int len)
 {
-        void *propval;
+        const void *propval;
         int proplen;
 
-        propval = fdt_getprop_w(fdt, nodeoffset, name, &proplen);
+        propval = fdt_getprop(fdt, nodeoffset, name, &proplen);
         if (! propval)
                 return proplen;
 
         if (proplen != len)
                 return -FDT_ERR_NOSPACE;
 
-        memcpy(propval, val, len);
-        return 0;
+        return fdt_setprop_inplace_namelen_partial(fdt, nodeoffset, name,
+                                                   strlen(name), 0,
+                                                   val, len);
 }
 
 static void _fdt_nop_region(void *start, int len)
diff --git a/scripts/dtc/libfdt/libfdt.h b/scripts/dtc/libfdt/libfdt.h
index 59ca33976e56..b842b156fa17 100644
--- a/scripts/dtc/libfdt/libfdt.h
+++ b/scripts/dtc/libfdt/libfdt.h
@@ -61,7 +61,7 @@
 #define FDT_ERR_NOTFOUND        1
         /* FDT_ERR_NOTFOUND: The requested node or property does not exist */
 #define FDT_ERR_EXISTS          2
-        /* FDT_ERR_EXISTS: Attemped to create a node or property which
+        /* FDT_ERR_EXISTS: Attempted to create a node or property which
          * already exists */
 #define FDT_ERR_NOSPACE         3
         /* FDT_ERR_NOSPACE: Operation needed to expand the device
@@ -79,8 +79,10 @@
          * (e.g. missing a leading / for a function which requires an
          * absolute path) */
 #define FDT_ERR_BADPHANDLE      6
-        /* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle
-         * value.  phandle values of 0 and -1 are not permitted. */
+        /* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle.
+         * This can be caused either by an invalid phandle property
+         * length, or the phandle value was either 0 or -1, which are
+         * not permitted. */
 #define FDT_ERR_BADSTATE        7
         /* FDT_ERR_BADSTATE: Function was passed an incomplete device
          * tree created by the sequential-write functions, which is
@@ -126,7 +128,16 @@
          * value. For example: a property expected to contain a string list
          * is not NUL-terminated within the length of its value. */
 
-#define FDT_ERR_MAX             15
+#define FDT_ERR_BADOVERLAY      16
+        /* FDT_ERR_BADOVERLAY: The device tree overlay, while
+         * correctly structured, cannot be applied due to some
+         * unexpected or missing value, property or node. */
+
+#define FDT_ERR_NOPHANDLES      17
+        /* FDT_ERR_NOPHANDLES: The device tree doesn't have any
+         * phandle available anymore without causing an overflow */
+
+#define FDT_ERR_MAX             17
 
 /**********************************************************************/
 /* Low-level functions (you probably don't need these)                */
@@ -168,27 +179,55 @@ int fdt_first_subnode(const void *fdt, int offset);
  */
 int fdt_next_subnode(const void *fdt, int offset);
 
+/**
+ * fdt_for_each_subnode - iterate over all subnodes of a parent
+ *
+ * @node:       child node (int, lvalue)
+ * @fdt:        FDT blob (const void *)
+ * @parent:     parent node (int)
+ *
+ * This is actually a wrapper around a for loop and would be used like so:
+ *
+ *      fdt_for_each_subnode(node, fdt, parent) {
+ *              Use node
+ *              ...
+ *      }
+ *
+ *      if ((node < 0) && (node != -FDT_ERR_NOT_FOUND)) {
+ *              Error handling
+ *      }
+ *
+ * Note that this is implemented as a macro and @node is used as
+ * iterator in the loop. The parent variable be constant or even a
+ * literal.
+ *
+ */
+#define fdt_for_each_subnode(node, fdt, parent)         \
+        for (node = fdt_first_subnode(fdt, parent);     \
+             node >= 0;                                 \
+             node = fdt_next_subnode(fdt, node))
+
 /**********************************************************************/
 /* General functions                                                  */
 /**********************************************************************/
 
 #define fdt_get_header(fdt, field) \
         (fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
-#define fdt_magic(fdt)                  (fdt_get_header(fdt, magic))
+#define fdt_magic(fdt)                  (fdt_get_header(fdt, magic))
 #define fdt_totalsize(fdt)              (fdt_get_header(fdt, totalsize))
 #define fdt_off_dt_struct(fdt)          (fdt_get_header(fdt, off_dt_struct))
 #define fdt_off_dt_strings(fdt)         (fdt_get_header(fdt, off_dt_strings))
 #define fdt_off_mem_rsvmap(fdt)         (fdt_get_header(fdt, off_mem_rsvmap))
 #define fdt_version(fdt)                (fdt_get_header(fdt, version))
-#define fdt_last_comp_version(fdt)      (fdt_get_header(fdt, last_comp_version))
-#define fdt_boot_cpuid_phys(fdt)        (fdt_get_header(fdt, boot_cpuid_phys))
-#define fdt_size_dt_strings(fdt)        (fdt_get_header(fdt, size_dt_strings))
+#define fdt_last_comp_version(fdt)      (fdt_get_header(fdt, last_comp_version))
+#define fdt_boot_cpuid_phys(fdt)        (fdt_get_header(fdt, boot_cpuid_phys))
+#define fdt_size_dt_strings(fdt)        (fdt_get_header(fdt, size_dt_strings))
 #define fdt_size_dt_struct(fdt)         (fdt_get_header(fdt, size_dt_struct))
 
 #define __fdt_set_hdr(name) \
         static inline void fdt_set_##name(void *fdt, uint32_t val) \
         { \
-                struct fdt_header *fdth = (struct fdt_header*)fdt; \
+                struct fdt_header *fdth = (struct fdt_header *)fdt; \
                 fdth->name = cpu_to_fdt32(val); \
         }
 __fdt_set_hdr(magic);
@@ -259,6 +298,21 @@ int fdt_move(const void *fdt, void *buf, int bufsize);
 const char *fdt_string(const void *fdt, int stroffset);
 
 /**
+ * fdt_get_max_phandle - retrieves the highest phandle in a tree
+ * @fdt: pointer to the device tree blob
+ *
+ * fdt_get_max_phandle retrieves the highest phandle in the given
+ * device tree. This will ignore badly formatted phandles, or phandles
+ * with a value of 0 or -1.
+ *
+ * returns:
+ *      the highest phandle on success
+ *      0, if no phandle was found in the device tree
+ *      -1, if an error occurred
+ */
+uint32_t fdt_get_max_phandle(const void *fdt);
+
+/**
  * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
  * @fdt: pointer to the device tree blob
  *
@@ -318,8 +372,9 @@ int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
  * returns:
  *      structure block offset of the requested subnode (>=0), on success
  *      -FDT_ERR_NOTFOUND, if the requested subnode does not exist
- *      -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
- *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
+ *              tag
+ *      -FDT_ERR_BADMAGIC,
  *      -FDT_ERR_BADVERSION,
  *      -FDT_ERR_BADSTATE,
  *      -FDT_ERR_BADSTRUCTURE,
@@ -351,7 +406,8 @@ int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen);
  * address).
  *
  * returns:
- *      structure block offset of the node with the requested path (>=0), on success
+ *      structure block offset of the node with the requested path (>=0), on
+ *              success
  *      -FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
  *      -FDT_ERR_NOTFOUND, if the requested node does not exist
  *      -FDT_ERR_BADMAGIC,
@@ -375,10 +431,12 @@ int fdt_path_offset(const void *fdt, const char *path);
  *
  * returns:
  *      pointer to the node's name, on success
- *              If lenp is non-NULL, *lenp contains the length of that name (>=0)
+ *              If lenp is non-NULL, *lenp contains the length of that name
+ *                      (>=0)
  *      NULL, on error
  *              if lenp is non-NULL *lenp contains an error code (<0):
- *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
+ *                      tag
  *              -FDT_ERR_BADMAGIC,
  *              -FDT_ERR_BADVERSION,
  *              -FDT_ERR_BADSTATE, standard meanings
@@ -427,6 +485,33 @@ int fdt_first_property_offset(const void *fdt, int nodeoffset);
 int fdt_next_property_offset(const void *fdt, int offset);
 
 /**
+ * fdt_for_each_property_offset - iterate over all properties of a node
+ *
+ * @property_offset:    property offset (int, lvalue)
+ * @fdt:                FDT blob (const void *)
+ * @node:               node offset (int)
+ *
+ * This is actually a wrapper around a for loop and would be used like so:
+ *
+ *      fdt_for_each_property_offset(property, fdt, node) {
+ *              Use property
+ *              ...
+ *      }
+ *
+ *      if ((property < 0) && (property != -FDT_ERR_NOT_FOUND)) {
+ *              Error handling
+ *      }
+ *
+ * Note that this is implemented as a macro and property is used as
+ * iterator in the loop. The node variable can be constant or even a
+ * literal.
+ */
+#define fdt_for_each_property_offset(property, fdt, node)       \
+        for (property = fdt_first_property_offset(fdt, node);   \
+             property >= 0;                                     \
+             property = fdt_next_property_offset(fdt, property))
+
+/**
  * fdt_get_property_by_offset - retrieve the property at a given offset
  * @fdt: pointer to the device tree blob
  * @offset: offset of the property to retrieve
@@ -490,7 +575,8 @@ const struct fdt_property *fdt_get_property_namelen(const void *fdt,
  *      NULL, on error
  *              if lenp is non-NULL, *lenp contains an error code (<0):
  *              -FDT_ERR_NOTFOUND, node does not have named property
- *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
+ *                      tag
  *              -FDT_ERR_BADMAGIC,
  *              -FDT_ERR_BADVERSION,
  *              -FDT_ERR_BADSTATE,
@@ -554,6 +640,13 @@ const void *fdt_getprop_by_offset(const void *fdt, int offset,
  */
 const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
                                 const char *name, int namelen, int *lenp);
+static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
+                                          const char *name, int namelen,
+                                          int *lenp)
+{
+        return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
+                                                      namelen, lenp);
+}
 
 /**
  * fdt_getprop - retrieve the value of a given property
@@ -575,7 +668,8 @@ const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
  *      NULL, on error
  *              if lenp is non-NULL, *lenp contains an error code (<0):
  *              -FDT_ERR_NOTFOUND, node does not have named property
- *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
+ *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
+ *                      tag
  *              -FDT_ERR_BADMAGIC,
  *              -FDT_ERR_BADVERSION,
  *              -FDT_ERR_BADSTATE,
@@ -617,7 +711,7 @@ const char *fdt_get_alias_namelen(const void *fdt,
                                   const char *name, int namelen);
 
 /**
- * fdt_get_alias - retreive the path referenced by a given alias
+ * fdt_get_alias - retrieve the path referenced by a given alias
  * @fdt: pointer to the device tree blob
  * @name: name of the alias th look up
  *
@@ -647,7 +741,7 @@ const char *fdt_get_alias(const void *fdt, const char *name);
  *      0, on success
  *              buf contains the absolute path of the node at
  *              nodeoffset, as a NUL-terminated string.
- *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
  *      -FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
  *              characters and will not fit in the given buffer.
  *      -FDT_ERR_BADMAGIC,
@@ -677,11 +771,11 @@ int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
  * structure from the start to nodeoffset.
  *
  * returns:
-
  *      structure block offset of the node at node offset's ancestor
  *              of depth supernodedepth (>=0), on success
- *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
-*       -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of nodeoffset
+ *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *      -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
+ *              nodeoffset
  *      -FDT_ERR_BADMAGIC,
  *      -FDT_ERR_BADVERSION,
  *      -FDT_ERR_BADSTATE,
@@ -703,7 +797,7 @@ int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
  *
  * returns:
  *      depth of the node at nodeoffset (>=0), on success
- *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
  *      -FDT_ERR_BADMAGIC,
  *      -FDT_ERR_BADVERSION,
  *      -FDT_ERR_BADSTATE,
@@ -726,7 +820,7 @@ int fdt_node_depth(const void *fdt, int nodeoffset);
  * returns:
  *      structure block offset of the parent of the node at nodeoffset
  *              (>=0), on success
- *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
  *      -FDT_ERR_BADMAGIC,
  *      -FDT_ERR_BADVERSION,
  *      -FDT_ERR_BADSTATE,
@@ -766,7 +860,7 @@ int fdt_parent_offset(const void *fdt, int nodeoffset);
  *               on success
  *      -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
  *              tree after startoffset
- *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
  *      -FDT_ERR_BADMAGIC,
  *      -FDT_ERR_BADVERSION,
  *      -FDT_ERR_BADSTATE,
@@ -813,7 +907,7 @@ int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
  *      1, if the node has a 'compatible' property, but it does not list
  *              the given string
  *      -FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
- *      -FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
+ *      -FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
  *      -FDT_ERR_BADMAGIC,
  *      -FDT_ERR_BADVERSION,
  *      -FDT_ERR_BADSTATE,
@@ -850,7 +944,7 @@ int fdt_node_check_compatible(const void *fdt, int nodeoffset,
  *               on success
  *      -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
  *              tree after startoffset
- *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
+ *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
  *      -FDT_ERR_BADMAGIC,
  *      -FDT_ERR_BADVERSION,
  *      -FDT_ERR_BADSTATE,
@@ -960,7 +1054,8 @@ const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
  * returns:
  *      0 <= n < FDT_MAX_NCELLS, on success
  *      2, if the node has no #address-cells property
- *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid #address-cells property
+ *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
+ *              #address-cells property
  *      -FDT_ERR_BADMAGIC,
  *      -FDT_ERR_BADVERSION,
  *      -FDT_ERR_BADSTATE,
@@ -980,7 +1075,8 @@ int fdt_address_cells(const void *fdt, int nodeoffset);
  * returns:
  *      0 <= n < FDT_MAX_NCELLS, on success
  *      2, if the node has no #address-cells property
- *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid #size-cells property
+ *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
+ *              #size-cells property
  *      -FDT_ERR_BADMAGIC,
  *      -FDT_ERR_BADVERSION,
  *      -FDT_ERR_BADSTATE,
@@ -995,6 +1091,27 @@ int fdt_size_cells(const void *fdt, int nodeoffset);
 /**********************************************************************/
 
 /**
+ * fdt_setprop_inplace_namelen_partial - change a property's value,
+ *                                       but not its size
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @namelen: number of characters of name to consider
+ * @idx: index of the property to change in the array
+ * @val: pointer to data to replace the property value with
+ * @len: length of the property value
+ *
+ * Identical to fdt_setprop_inplace(), but modifies the given property
+ * starting from the given index, and using only the first characters
+ * of the name. It is useful when you want to manipulate only one value of
+ * an array and you have a string that doesn't end with \0.
+ */
+int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
+                                        const char *name, int namelen,
+                                        uint32_t idx, const void *val,
+                                        int len);
+
+/**
  * 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
@@ -1604,9 +1721,11 @@ int fdt_add_subnode_namelen(void *fdt, int parentoffset,
  * change the offsets of some existing nodes.
 
  * returns:
- *      structure block offset of the created nodeequested subnode (>=0), on success
+ *      structure block offset of the created nodeequested subnode (>=0), on
+ *              success
  *      -FDT_ERR_NOTFOUND, if the requested subnode does not exist
- *      -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
+ *      -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
+ *              tag
  *      -FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
  *              the given name
  *      -FDT_ERR_NOSPACE, if there is insufficient free space in the
@@ -1644,6 +1763,37 @@ int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
  */
 int fdt_del_node(void *fdt, int nodeoffset);
 
+/**
+ * fdt_overlay_apply - Applies a DT overlay on a base DT
+ * @fdt: pointer to the base device tree blob
+ * @fdto: pointer to the device tree overlay blob
+ *
+ * fdt_overlay_apply() will apply the given device tree overlay on the
+ * given base device tree.
+ *
+ * Expect the base device tree to be modified, even if the function
+ * returns an error.
+ *
+ * returns:
+ *      0, on success
+ *      -FDT_ERR_NOSPACE, there's not enough space in the base device tree
+ *      -FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
+ *              properties in the base DT
+ *      -FDT_ERR_BADPHANDLE,
+ *      -FDT_ERR_BADOVERLAY,
+ *      -FDT_ERR_NOPHANDLES,
+ *      -FDT_ERR_INTERNAL,
+ *      -FDT_ERR_BADLAYOUT,
+ *      -FDT_ERR_BADMAGIC,
+ *      -FDT_ERR_BADOFFSET,
+ *      -FDT_ERR_BADPATH,
+ *      -FDT_ERR_BADVERSION,
+ *      -FDT_ERR_BADSTRUCTURE,
+ *      -FDT_ERR_BADSTATE,
+ *      -FDT_ERR_TRUNCATED, standard meanings
+ */
+int fdt_overlay_apply(void *fdt, void *fdto);
+
 /**********************************************************************/
 /* Debugging / informational functions                                */
 /**********************************************************************/
diff --git a/scripts/dtc/libfdt/libfdt_env.h b/scripts/dtc/libfdt/libfdt_env.h
index 9dea97dfff81..99f936dacc60 100644
--- a/scripts/dtc/libfdt/libfdt_env.h
+++ b/scripts/dtc/libfdt/libfdt_env.h
@@ -54,6 +54,7 @@
 
 #include <stddef.h>
 #include <stdint.h>
+#include <stdlib.h>
 #include <string.h>
 
 #ifdef __CHECKER__