libfdt: Update to latest pylibfdt implementation

The enhanced pylibfdt support in U-Boot needed for binman was a
placeholder while upstreaming of this work continued. This is now
complete, so bring in the changes and update the tools as needed.

There are quite a few changes since we decided to split the
implementation into three fdt classes instead of two.

The Fdt.del_node() method was unfortunately missed in this process and
will be dealt with later. It exists in U-Boot but not upstream.

Further syncing of libfdt probably needs to wait until we assess the
code-size impact of all the new checking code on SPL and possibly provide
a way to disable it.

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 239 insertions, 225 deletions

diff --git a/scripts/dtc/pylibfdt/libfdt.i_shipped b/scripts/dtc/pylibfdt/libfdt.i_shipped
index e180ee9308..0f17c5879e 100644
--- a/scripts/dtc/pylibfdt/libfdt.i_shipped
+++ b/scripts/dtc/pylibfdt/libfdt.i_shipped
@@ -18,7 +18,8 @@
  * a struct called fdt_property. That struct causes swig to create a class in
  * libfdt.py called fdt_property(), which confuses things.
  */
-static int _fdt_property(void *fdt, const char *name, const char *val, int len)
+static int fdt_property_stub(void *fdt, const char *name, const char *val,
+                             int len)
 {
     return fdt_property(fdt, name, val, len);
 }
@@ -54,6 +55,7 @@ import struct
 # Pass this as the 'quiet' parameter to return -ENOTFOUND on NOTFOUND errors,
 # instead of raising an exception.
 QUIET_NOTFOUND = (NOTFOUND,)
+QUIET_NOSPACE = (NOSPACE,)
 
 
 class FdtException(Exception):
@@ -119,23 +121,18 @@ def check_err_null(val, quiet=()):
             raise FdtException(val)
     return val
 
+class FdtRo(object):
+    """Class for a read-only device-tree
 
-class Fdt:
-    """Device tree class, supporting all operations
-
-    The Fdt object is created is created from a device tree binary file,
-    e.g. with something like:
+    This is a base class used by FdtRw (read-write access) and FdtSw
+    (sequential-write access). It implements read-only access to the
+    device tree.
 
-       fdt = Fdt(open("filename.dtb").read())
-
-    Operations can then be performed using the methods in this class. Each
-    method xxx(args...) corresponds to a libfdt function fdt_xxx(fdt, args...).
+    Here are the three classes and when you should use them:
 
-    All methods raise an FdtException if an error occurs. To avoid this
-    behaviour a 'quiet' parameter is provided for some functions. This
-    defaults to empty, but you can pass a list of errors that you expect.
-    If one of these errors occurs, the function will return an error number
-    (e.g. -NOTFOUND).
+        FdtRo - read-only access to an existing FDT
+        FdtRw - read-write access to an existing FDT (most common case)
+        FdtSw - for creating a new FDT, as well as allowing read-only access
     """
     def __init__(self, data):
         self._fdt = bytearray(data)
@@ -157,12 +154,14 @@ class Fdt:
 
         Args:
             nodeoffset: Node offset of previous node
-            depth: On input, the depth of the node at nodeoffset. On output, the
-               depth of the returned node
+            depth: The depth of the node at nodeoffset. This is used to
+                calculate the depth of the returned node
             quiet: Errors to ignore (empty to raise on all errors)
 
         Returns:
-            The offset of the next node, if any
+            Typle:
+                Offset of the next node, if any, else a -ve error
+                Depth of the returned node, if any, else undefined
 
         Raises:
             FdtException if no more nodes found or other error occurs
@@ -205,7 +204,7 @@ class Fdt:
         Returns:
             Magic word
         """
-        return fdt_magic(self._fdt) & 0xffffffff
+        return fdt_magic(self._fdt)
 
     def totalsize(self):
         """Return the total size of the device tree
@@ -213,7 +212,7 @@ class Fdt:
         Returns:
             Total tree size in bytes
         """
-        return check_err(fdt_totalsize(self._fdt))
+        return fdt_totalsize(self._fdt)
 
     def off_dt_struct(self):
         """Return the start of the device-tree struct area
@@ -221,7 +220,7 @@ class Fdt:
         Returns:
             Start offset of struct area
         """
-        return check_err(fdt_off_dt_struct(self._fdt))
+        return fdt_off_dt_struct(self._fdt)
 
     def off_dt_strings(self):
         """Return the start of the device-tree string area
@@ -229,7 +228,7 @@ class Fdt:
         Returns:
             Start offset of string area
         """
-        return check_err(fdt_off_dt_strings(self._fdt))
+        return fdt_off_dt_strings(self._fdt)
 
     def off_mem_rsvmap(self):
         """Return the start of the memory reserve map
@@ -237,7 +236,7 @@ class Fdt:
         Returns:
             Start offset of memory reserve map
         """
-        return check_err(fdt_off_mem_rsvmap(self._fdt))
+        return fdt_off_mem_rsvmap(self._fdt)
 
     def version(self):
         """Return the version of the device tree
@@ -245,7 +244,7 @@ class Fdt:
         Returns:
             Version number of the device tree
         """
-        return check_err(fdt_version(self._fdt))
+        return fdt_version(self._fdt)
 
     def last_comp_version(self):
         """Return the last compatible version of the device tree
@@ -253,7 +252,7 @@ class Fdt:
         Returns:
             Last compatible version number of the device tree
         """
-        return check_err(fdt_last_comp_version(self._fdt))
+        return fdt_last_comp_version(self._fdt)
 
     def boot_cpuid_phys(self):
         """Return the physical boot CPU ID
@@ -261,7 +260,7 @@ class Fdt:
         Returns:
             Physical boot CPU ID
         """
-        return check_err(fdt_boot_cpuid_phys(self._fdt))
+        return fdt_boot_cpuid_phys(self._fdt)
 
     def size_dt_strings(self):
         """Return the start of the device-tree string area
@@ -269,7 +268,7 @@ class Fdt:
         Returns:
             Start offset of string area
         """
-        return check_err(fdt_size_dt_strings(self._fdt))
+        return fdt_size_dt_strings(self._fdt)
 
     def size_dt_struct(self):
         """Return the start of the device-tree struct area
@@ -277,7 +276,7 @@ class Fdt:
         Returns:
             Start offset of struct area
         """
-        return check_err(fdt_size_dt_struct(self._fdt))
+        return fdt_size_dt_struct(self._fdt)
 
     def num_mem_rsv(self, quiet=()):
         """Return the number of memory reserve-map records
@@ -398,26 +397,90 @@ class Fdt:
             return pdata
         return Property(pdata[0], pdata[1])
 
-    def get_property(self, nodeoffset, prop_name, quiet=()):
-        """Obtains a property by name
+    def getprop(self, nodeoffset, prop_name, quiet=()):
+        """Get a property from a node
 
         Args:
-            nodeoffset: Offset to the node to check
+            nodeoffset: Node offset containing property to get
             prop_name: Name of property to get
             quiet: Errors to ignore (empty to raise on all errors)
 
         Returns:
-            Property object, or None if not found
+            Value of property as a Property object (which can be used as a
+               bytearray/string), or -ve error number. On failure, returns an
+               integer error
 
         Raises:
-            FdtException on error (e.g. invalid prop_offset or device
-            tree format)
+            FdtError if any error occurs (e.g. the property is not found)
         """
-        pdata = check_err_null(
-                fdt_get_property(self._fdt, nodeoffset, prop_name), quiet)
+        pdata = check_err_null(fdt_getprop(self._fdt, nodeoffset, prop_name),
+                               quiet)
         if isinstance(pdata, (int)):
             return pdata
-        return Property(pdata[0], pdata[1])
+        return Property(prop_name, bytearray(pdata[0]))
+
+    def get_phandle(self, nodeoffset):
+        """Get the phandle of a node
+
+        Args:
+            nodeoffset: Node offset to check
+
+        Returns:
+            phandle of node, or 0 if the node has no phandle or another error
+            occurs
+        """
+        return fdt_get_phandle(self._fdt, nodeoffset)
+
+    def parent_offset(self, nodeoffset, quiet=()):
+        """Get the offset of a node's parent
+
+        Args:
+            nodeoffset: Node offset to check
+            quiet: Errors to ignore (empty to raise on all errors)
+
+        Returns:
+            The offset of the parent node, if any
+
+        Raises:
+            FdtException if no parent found or other error occurs
+        """
+        return check_err(fdt_parent_offset(self._fdt, nodeoffset), quiet)
+
+    def node_offset_by_phandle(self, phandle, quiet=()):
+        """Get the offset of a node with the given phandle
+
+        Args:
+            phandle: Phandle to search for
+            quiet: Errors to ignore (empty to raise on all errors)
+
+        Returns:
+            The offset of node with that phandle, if any
+
+        Raises:
+            FdtException if no node found or other error occurs
+        """
+        return check_err(fdt_node_offset_by_phandle(self._fdt, phandle), quiet)
+
+
+class Fdt(FdtRo):
+    """Device tree class, supporting all operations
+
+    The Fdt object is created is created from a device tree binary file,
+    e.g. with something like:
+
+       fdt = Fdt(open("filename.dtb").read())
+
+    Operations can then be performed using the methods in this class. Each
+    method xxx(args...) corresponds to a libfdt function fdt_xxx(fdt, args...).
+
+    All methods raise an FdtException if an error occurs. To avoid this
+    behaviour a 'quiet' parameter is provided for some functions. This
+    defaults to empty, but you can pass a list of errors that you expect.
+    If one of these errors occurs, the function will return an error number
+    (e.g. -NOTFOUND).
+    """
+    def __init__(self, data):
+        FdtRo.__init__(self, data)
 
     @staticmethod
     def create_empty_tree(size, quiet=()):
@@ -435,18 +498,18 @@ class Fdt:
             return err
         return Fdt(data)
 
-    def open_into(self, size, quiet=()):
+    def resize(self, size, quiet=()):
         """Move the device tree into a larger or smaller space
 
         This creates a new device tree of size @size and moves the existing
         device tree contents over to that. It can be used to create more space
-        in a device tree.
+        in a device tree. Note that the Fdt object remains the same, but it
+        now has a new bytearray holding the contents.
 
         Args:
             size: Required new size of device tree in bytes
         """
         fdt = bytearray(size)
-        fdt[:len(self._fdt)] = self._fdt
         err = check_err(fdt_open_into(self._fdt, fdt, size), quiet)
         if err:
             return err
@@ -460,6 +523,9 @@ class Fdt:
         Args:
             quiet: Errors to ignore (empty to raise on all errors)
 
+        Returns:
+            Error code, or 0 if OK
+
         Raises:
             FdtException if any error occurs
         """
@@ -469,79 +535,12 @@ class Fdt:
         del self._fdt[self.totalsize():]
         return err
 
-    def getprop(self, nodeoffset, prop_name, quiet=()):
-        """Get a property from a node
-
-        Args:
-            nodeoffset: Node offset containing property to get
-            prop_name: Name of property to get
-            quiet: Errors to ignore (empty to raise on all errors)
-
-        Returns:
-            Value of property as a string, or -ve error number
-
-        Raises:
-            FdtError if any error occurs (e.g. the property is not found)
-        """
-        pdata = check_err_null(fdt_getprop(self._fdt, nodeoffset, prop_name),
-                               quiet)
-        if isinstance(pdata, (int)):
-            return pdata
-        return str(pdata[0])
-
-    def getprop_obj(self, nodeoffset, prop_name, quiet=()):
-        """Get a property from a node as a Property object
-
-        Args:
-            nodeoffset: Node offset containing property to get
-            prop_name: Name of property to get
-            quiet: Errors to ignore (empty to raise on all errors)
-
-        Returns:
-            Property object, or None if not found
-
-        Raises:
-            FdtError if any error occurs (e.g. the property is not found)
-        """
-        pdata = check_err_null(fdt_getprop(self._fdt, nodeoffset, prop_name),
-                               quiet)
-        if isinstance(pdata, (int)):
-            return None
-        return Property(prop_name, bytearray(pdata[0]))
-
-    def get_phandle(self, nodeoffset):
-        """Get the phandle of a node
-
-        Args:
-            nodeoffset: Node offset to check
-
-        Returns:
-            phandle of node, or 0 if the node has no phandle or another error
-            occurs
-        """
-        return fdt_get_phandle(self._fdt, nodeoffset)
-
-    def parent_offset(self, nodeoffset, quiet=()):
-        """Get the offset of a node's parent
-
-        Args:
-            nodeoffset: Node offset to check
-            quiet: Errors to ignore (empty to raise on all errors)
-
-        Returns:
-            The offset of the parent node, if any
-
-        Raises:
-            FdtException if no parent found or other error occurs
-        """
-        return check_err(fdt_parent_offset(self._fdt, nodeoffset), quiet)
-
     def set_name(self, nodeoffset, name, quiet=()):
         """Set the name of a node
 
         Args:
             nodeoffset: Node offset of node to update
-            name: New node name
+            name: New node name (string without \0)
 
         Returns:
             Error code, or 0 if OK
@@ -549,6 +548,8 @@ class Fdt:
         Raises:
             FdtException if no parent found or other error occurs
         """
+        if chr(0) in name:
+            raise ValueError('Property contains embedded nul characters')
         return check_err(fdt_set_name(self._fdt, nodeoffset, name), quiet)
 
     def setprop(self, nodeoffset, prop_name, val, quiet=()):
@@ -613,7 +614,8 @@ class Fdt:
         Args:
             nodeoffset: Node offset containing the property to create/update
             prop_name: Name of property
-            val: Value to write (string without nul terminator)
+            val: Value to write (string without nul terminator). Unicode is
+                supposed by encoding to UTF-8
             quiet: Errors to ignore (empty to raise on all errors)
 
         Returns:
@@ -622,7 +624,7 @@ class Fdt:
         Raises:
             FdtException if no parent found or other error occurs
         """
-        val += '\0'
+        val = val.encode('utf-8') + '\0'
         return check_err(fdt_setprop(self._fdt, nodeoffset, prop_name,
                                      val, len(val)), quiet)
 
@@ -638,21 +640,6 @@ class Fdt:
         """
         return check_err(fdt_delprop(self._fdt, nodeoffset, prop_name))
 
-    def node_offset_by_phandle(self, phandle, quiet=()):
-        """Get the offset of a node with the given phandle
-
-        Args:
-            phandle: Phandle to search for
-            quiet: Errors to ignore (empty to raise on all errors)
-
-        Returns:
-            The offset of node with that phandle, if any
-
-        Raises:
-            FdtException if no node found or other error occurs
-        """
-        return check_err(fdt_node_offset_by_phandle(self._fdt, phandle), quiet)
-
     def del_node(self, nodeoffset):
         """Delete a node
 
@@ -696,16 +683,20 @@ class Property(bytearray):
         return self.as_cell('q')
 
     def as_str(self):
-        return self[:-1]
+        """Unicode is supported by decoding from UTF-8"""
+        if self[-1] != 0:
+            raise ValueError('Property lacks nul termination')
+        if 0 in self[:-1]:
+            raise ValueError('Property contains embedded nul characters')
+        return self[:-1].decode('utf-8')
 
 
-class FdtSw(object):
+class FdtSw(FdtRo):
     """Software interface to create a device tree from scratch
 
     The methods in this class work by adding to an existing 'partial' device
     tree buffer of a fixed size created by instantiating this class. When the
-    tree is complete, call finish() to complete the device tree so that it can
-    be used.
+    tree is complete, call as_fdt() to obtain a device tree ready to be used.
 
     Similarly with nodes, a new node is started with begin_node() and finished
     with end_node().
@@ -713,58 +704,87 @@ class FdtSw(object):
     The context manager functions can be used to make this a bit easier:
 
     # First create the device tree with a node and property:
-    with FdtSw(small_size) as sw:
-        with sw.AddNode('node'):
-            sw.property_u32('reg', 2)
-    fdt = sw.AsFdt()
+    sw = FdtSw()
+    with sw.add_node('node'):
+        sw.property_u32('reg', 2)
+    fdt = sw.as_fdt()
 
     # Now we can use it as a real device tree
     fdt.setprop_u32(0, 'reg', 3)
+
+    The size hint provides a starting size for the space to be used by the
+    device tree. This will be increased automatically as needed as new items
+    are added to the tree.
     """
-    def __init__(self, size, quiet=()):
-        fdtrw = bytearray(size)
-        err = check_err(fdt_create(fdtrw, size))
-        if err:
-            return err
-        self._fdtrw = fdtrw
+    INC_SIZE = 1024  # Expand size by this much when out of space
 
-    def __enter__(self):
-        """Contact manager to use to create a device tree via software"""
-        return self
+    def __init__(self, size_hint=None):
+        """Create a new FdtSw object
 
-    def __exit__(self, type, value, traceback):
-        check_err(fdt_finish(self._fdtrw))
+        Args:
+            size_hint: A hint as to the initial size to use
+
+        Raises:
+            ValueError if size_hint is negative
 
-    def AsFdt(self):
+        Returns:
+            FdtSw object on success, else integer error code (if not raising)
+        """
+        if not size_hint:
+            size_hint = self.INC_SIZE
+        fdtsw = bytearray(size_hint)
+        err = check_err(fdt_create(fdtsw, size_hint))
+        if err:
+            return err
+        self._fdt = fdtsw
+
+    def as_fdt(self):
         """Convert a FdtSw into an Fdt so it can be accessed as normal
 
-        Note that finish() must be called before this function will work. If
-        you are using the context manager (see 'with' code in the FdtSw class
-        comment) then this will happen automatically.
+        Creates a new Fdt object from the work-in-progress device tree. This
+        does not call fdt_finish() on the current object, so it is possible to
+        add more nodes/properties and call as_fdt() again to get an updated
+        tree.
 
         Returns:
             Fdt object allowing access to the newly created device tree
         """
-        return Fdt(self._fdtrw)
+        fdtsw = bytearray(self._fdt)
+        check_err(fdt_finish(fdtsw))
+        return Fdt(fdtsw)
 
-    def resize(self, size, quiet=()):
+    def check_space(self, val):
+        """Check if we need to add more space to the FDT
+
+        This should be called with the error code from an operation. If this is
+        -NOSPACE then the FDT will be expanded to have more space, and True will
+        be returned, indicating that the operation needs to be tried again.
+
+        Args:
+            val: Return value from the operation that was attempted
+
+        Returns:
+            True if the operation must be retried, else False
+        """
+        if check_err(val, QUIET_NOSPACE) < 0:
+            self.resize(len(self._fdt) + self.INC_SIZE)
+            return True
+        return False
+
+    def resize(self, size):
         """Resize the buffer to accommodate a larger tree
 
         Args:
             size: New size of tree
-            quiet: Errors to ignore (empty to raise on all errors)
 
         Raises:
-            FdtException if no node found or other error occurs
+            FdtException on any error
         """
         fdt = bytearray(size)
-        fdt[:len(self._fdtrw)] = self._fdtrw
-        err = check_err(fdt_resize(self._fdtrw, fdt, size), quiet)
-        if err:
-            return err
-        self._fdtrw = fdt
+        err = check_err(fdt_resize(self._fdt, fdt, size))
+        self._fdt = fdt
 
-    def add_reservemap_entry(self, addr, size, quiet=()):
+    def add_reservemap_entry(self, addr, size):
         """Add a new memory reserve map entry
 
         Once finished adding, you must call finish_reservemap().
@@ -772,26 +792,24 @@ class FdtSw(object):
         Args:
             addr: 64-bit start address
             size: 64-bit size
-            quiet: Errors to ignore (empty to raise on all errors)
 
         Raises:
-            FdtException if no node found or other error occurs
+            FdtException on any error
         """
-        return check_err(fdt_add_reservemap_entry(self._fdtrw, addr, size),
-                         quiet)
+        while self.check_space(fdt_add_reservemap_entry(self._fdt, addr,
+                                                        size)):
+            pass
 
-    def finish_reservemap(self, quiet=()):
+    def finish_reservemap(self):
         """Indicate that there are no more reserve map entries to add
 
-        Args:
-            quiet: Errors to ignore (empty to raise on all errors)
-
         Raises:
-            FdtException if no node found or other error occurs
+            FdtException on any error
         """
-        return check_err(fdt_finish_reservemap(self._fdtrw), quiet)
+        while self.check_space(fdt_finish_reservemap(self._fdt)):
+            pass
 
-    def begin_node(self, name, quiet=()):
+    def begin_node(self, name):
         """Begin a new node
 
         Use this before adding properties to the node. Then call end_node() to
@@ -800,14 +818,14 @@ class FdtSw(object):
 
         Args:
             name: Name of node to begin
-            quiet: Errors to ignore (empty to raise on all errors)
 
         Raises:
-            FdtException if no node found or other error occurs
+            FdtException on any error
         """
-        return check_err(fdt_begin_node(self._fdtrw, name), quiet)
+        while self.check_space(fdt_begin_node(self._fdt, name)):
+            pass
 
-    def property_string(self, name, string, quiet=()):
+    def property_string(self, name, string):
         """Add a property with a string value
 
         The string will be nul-terminated when written to the device tree
@@ -815,14 +833,14 @@ class FdtSw(object):
         Args:
             name: Name of property to add
             string: String value of property
-            quiet: Errors to ignore (empty to raise on all errors)
 
         Raises:
-            FdtException if no node found or other error occurs
+            FdtException on any error
         """
-        return check_err(fdt_property_string(self._fdtrw, name, string), quiet)
+        while self.check_space(fdt_property_string(self._fdt, name, string)):
+            pass
 
-    def property_u32(self, name, val, quiet=()):
+    def property_u32(self, name, val):
         """Add a property with a 32-bit value
 
         Write a single-cell value to the device tree
@@ -830,14 +848,14 @@ class FdtSw(object):
         Args:
             name: Name of property to add
             val: Value of property
-            quiet: Errors to ignore (empty to raise on all errors)
 
         Raises:
-            FdtException if no node found or other error occurs
+            FdtException on any error
         """
-        return check_err(fdt_property_u32(self._fdtrw, name, val), quiet)
+        while self.check_space(fdt_property_u32(self._fdt, name, val)):
+            pass
 
-    def property_u64(self, name, val, quiet=()):
+    def property_u64(self, name, val):
         """Add a property with a 64-bit value
 
         Write a double-cell value to the device tree in big-endian format
@@ -845,14 +863,14 @@ class FdtSw(object):
         Args:
             name: Name of property to add
             val: Value of property
-            quiet: Errors to ignore (empty to raise on all errors)
 
         Raises:
-            FdtException if no node found or other error occurs
+            FdtException on any error
         """
-        return check_err(fdt_property_u64(self._fdtrw, name, val), quiet)
+        while self.check_space(fdt_property_u64(self._fdt, name, val)):
+            pass
 
-    def property_cell(self, name, val, quiet=()):
+    def property_cell(self, name, val):
         """Add a property with a single-cell value
 
         Write a single-cell value to the device tree
@@ -863,11 +881,12 @@ class FdtSw(object):
             quiet: Errors to ignore (empty to raise on all errors)
 
         Raises:
-            FdtException if no node found or other error occurs
+            FdtException on any error
         """
-        return check_err(fdt_property_cell(self._fdtrw, name, val), quiet)
+        while self.check_space(fdt_property_cell(self._fdt, name, val)):
+            pass
 
-    def property(self, name, val, quiet=()):
+    def property(self, name, val):
         """Add a property
 
         Write a new property with the given value to the device tree. The value
@@ -879,11 +898,13 @@ class FdtSw(object):
             quiet: Errors to ignore (empty to raise on all errors)
 
         Raises:
-            FdtException if no node found or other error occurs
+            FdtException on any error
         """
-        return check_err(_fdt_property(self._fdtrw, name, val, len(val)), quiet)
+        while self.check_space(fdt_property_stub(self._fdt, name, val,
+                                                 len(val))):
+            pass
 
-    def end_node(self, quiet=()):
+    def end_node(self):
         """End a node
 
         Use this after adding properties to a node to close it off. You can also
@@ -893,24 +914,12 @@ class FdtSw(object):
             quiet: Errors to ignore (empty to raise on all errors)
 
         Raises:
-            FdtException if no node found or other error occurs
-        """
-        return check_err(fdt_end_node(self._fdtrw), quiet)
-
-    def finish(self, quiet=()):
-        """Finish writing the device tree
-
-        This closes off the device tree ready for use
-
-        Args:
-            quiet: Errors to ignore (empty to raise on all errors)
-
-        Raises:
-            FdtException if no node found or other error occurs
+            FdtException on any error
         """
-        return check_err(fdt_finish(self._fdtrw), quiet)
+        while self.check_space(fdt_end_node(self._fdt)):
+            pass
 
-    def AddNode(self, name):
+    def add_node(self, name):
         """Create a new context for adding a node
 
         When used in a 'with' clause this starts a new node and finishes it
@@ -919,7 +928,7 @@ class FdtSw(object):
         Args:
             name: Name of node to add
         """
-        return NodeAdder(self._fdtrw, name)
+        return NodeAdder(self, name)
 
 
 class NodeAdder():
@@ -927,26 +936,30 @@ class NodeAdder():
 
     This allows you to add nodes in a more natural way:
 
-        with fdtsw.AddNode('name'):
+        with fdtsw.add_node('name'):
             fdtsw.property_string('test', 'value')
 
     The node is automatically completed with a call to end_node() when the
     context exits.
     """
-    def __init__(self, fdt, name):
-        self._fdt = fdt
+    def __init__(self, fdtsw, name):
+        self._fdt = fdtsw
         self._name = name
 
     def __enter__(self):
-        check_err(fdt_begin_node(self._fdt, self._name))
+        self._fdt.begin_node(self._name)
 
     def __exit__(self, type, value, traceback):
-        check_err(fdt_end_node(self._fdt))
+        self._fdt.end_node()
 %}
 
 %rename(fdt_property) fdt_property_func;
 
-typedef int fdt32_t;
+/*
+ * fdt32_t is a big-endian 32-bit value defined to uint32_t in libfdt_env.h
+ * so use the same type here.
+ */
+typedef uint32_t fdt32_t;
 
 %include "libfdt/fdt.h"
 
@@ -1039,16 +1052,17 @@ typedef int fdt32_t;
 %warnfilter(302) fdt_property;
 
 /* These are macros in the header so have to be redefined here */
-int fdt_magic(const void *fdt);
-int fdt_totalsize(const void *fdt);
-int fdt_off_dt_struct(const void *fdt);
-int fdt_off_dt_strings(const void *fdt);
-int fdt_off_mem_rsvmap(const void *fdt);
-int fdt_version(const void *fdt);
-int fdt_last_comp_version(const void *fdt);
-int fdt_boot_cpuid_phys(const void *fdt);
-int fdt_size_dt_strings(const void *fdt);
-int fdt_size_dt_struct(const void *fdt);
+uint32_t fdt_magic(const void *fdt);
+uint32_t fdt_totalsize(const void *fdt);
+uint32_t fdt_off_dt_struct(const void *fdt);
+uint32_t fdt_off_dt_strings(const void *fdt);
+uint32_t fdt_off_mem_rsvmap(const void *fdt);
+uint32_t fdt_version(const void *fdt);
+uint32_t fdt_last_comp_version(const void *fdt);
+uint32_t fdt_boot_cpuid_phys(const void *fdt);
+uint32_t fdt_size_dt_strings(const void *fdt);
+uint32_t fdt_size_dt_struct(const void *fdt);
+
 int fdt_property_string(void *fdt, const char *name, const char *val);
 int fdt_property_cell(void *fdt, const char *name, uint32_t val);
 
@@ -1056,6 +1070,6 @@ int fdt_property_cell(void *fdt, const char *name, uint32_t val);
  * This function has a stub since the name fdt_property is used for both a
   * function and a struct, which confuses SWIG.
  */
-int _fdt_property(void *fdt, const char *name, const char *val, int len);
+int fdt_property_stub(void *fdt, const char *name, const char *val, int len);
 
 %include <../libfdt/libfdt.h>