1119 lines
33 KiB
Plaintext
1119 lines
33 KiB
Plaintext
/* SPDX-License-Identifier: GPL-2.0+ OR BSD-2-Clause */
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/*
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* pylibfdt - Flat Device Tree manipulation in Python
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* Copyright (C) 2017 Google, Inc.
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* Written by Simon Glass <sjg@chromium.org>
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*/
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%module libfdt
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%include <stdint.i>
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%{
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#define SWIG_FILE_WITH_INIT
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#include "libfdt.h"
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/*
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* We rename this function here to avoid problems with swig, since we also have
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* a struct called fdt_property. That struct causes swig to create a class in
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* libfdt.py called fdt_property(), which confuses things.
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*/
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static int fdt_property_stub(void *fdt, const char *name, const void *val,
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int len)
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{
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return fdt_property(fdt, name, val, len);
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}
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%}
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%pythoncode %{
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import struct
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# Error codes, corresponding to FDT_ERR_... in libfdt.h
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(NOTFOUND,
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EXISTS,
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NOSPACE,
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BADOFFSET,
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BADPATH,
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BADPHANDLE,
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BADSTATE,
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TRUNCATED,
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BADMAGIC,
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BADVERSION,
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BADSTRUCTURE,
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BADLAYOUT,
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INTERNAL,
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BADNCELLS,
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BADVALUE,
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BADOVERLAY,
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NOPHANDLES) = QUIET_ALL = range(1, 18)
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# QUIET_ALL can be passed as the 'quiet' parameter to avoid exceptions
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# altogether. All # functions passed this value will return an error instead
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# of raising an exception.
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# Pass this as the 'quiet' parameter to return -ENOTFOUND on NOTFOUND errors,
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# instead of raising an exception.
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QUIET_NOTFOUND = (NOTFOUND,)
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QUIET_NOSPACE = (NOSPACE,)
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class FdtException(Exception):
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"""An exception caused by an error such as one of the codes above"""
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def __init__(self, err):
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self.err = err
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def __str__(self):
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return 'pylibfdt error %d: %s' % (self.err, fdt_strerror(self.err))
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def strerror(fdt_err):
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"""Get the string for an error number
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Args:
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fdt_err: Error number (-ve)
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Returns:
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String containing the associated error
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"""
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return fdt_strerror(fdt_err)
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def check_err(val, quiet=()):
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"""Raise an error if the return value is -ve
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This is used to check for errors returned by libfdt C functions.
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Args:
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val: Return value from a libfdt function
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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val if val >= 0
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Raises
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FdtException if val < 0
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"""
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if isinstance(val, int) and val < 0:
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if -val not in quiet:
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raise FdtException(val)
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return val
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def check_err_null(val, quiet=()):
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"""Raise an error if the return value is NULL
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This is used to check for a NULL return value from certain libfdt C
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functions
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Args:
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val: Return value from a libfdt function
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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val if val is a list, None if not
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Raises
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FdtException if val indicates an error was reported and the error
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is not in @quiet.
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"""
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# Normally a list is returned which contains the data and its length.
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# If we get just an integer error code, it means the function failed.
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if not isinstance(val, list):
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if -val not in quiet:
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raise FdtException(val)
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return val
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class FdtRo(object):
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"""Class for a read-only device-tree
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This is a base class used by FdtRw (read-write access) and FdtSw
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(sequential-write access). It implements read-only access to the
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device tree.
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Here are the three classes and when you should use them:
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FdtRo - read-only access to an existing FDT
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FdtRw - read-write access to an existing FDT (most common case)
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FdtSw - for creating a new FDT, as well as allowing read-only access
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"""
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def __init__(self, data):
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self._fdt = bytearray(data)
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check_err(fdt_check_header(self._fdt));
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def as_bytearray(self):
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"""Get the device tree contents as a bytearray
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This can be passed directly to libfdt functions that access a
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const void * for the device tree.
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Returns:
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bytearray containing the device tree
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"""
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return bytearray(self._fdt)
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def next_node(self, nodeoffset, depth, quiet=()):
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"""Find the next subnode
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Args:
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nodeoffset: Node offset of previous node
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depth: The depth of the node at nodeoffset. This is used to
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calculate the depth of the returned node
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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Typle:
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Offset of the next node, if any, else a -ve error
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Depth of the returned node, if any, else undefined
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Raises:
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FdtException if no more nodes found or other error occurs
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"""
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return check_err(fdt_next_node(self._fdt, nodeoffset, depth), quiet)
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def first_subnode(self, nodeoffset, quiet=()):
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"""Find the first subnode of a parent node
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Args:
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nodeoffset: Node offset of parent node
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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The offset of the first subnode, if any
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Raises:
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FdtException if no subnodes found or other error occurs
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"""
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return check_err(fdt_first_subnode(self._fdt, nodeoffset), quiet)
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def next_subnode(self, nodeoffset, quiet=()):
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"""Find the next subnode
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Args:
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nodeoffset: Node offset of previous subnode
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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The offset of the next subnode, if any
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Raises:
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FdtException if no more subnodes found or other error occurs
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"""
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return check_err(fdt_next_subnode(self._fdt, nodeoffset), quiet)
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def magic(self):
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"""Return the magic word from the header
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Returns:
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Magic word
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"""
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return fdt_magic(self._fdt)
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def totalsize(self):
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"""Return the total size of the device tree
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Returns:
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Total tree size in bytes
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"""
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return fdt_totalsize(self._fdt)
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def off_dt_struct(self):
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"""Return the start of the device-tree struct area
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Returns:
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Start offset of struct area
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"""
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return fdt_off_dt_struct(self._fdt)
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def off_dt_strings(self):
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"""Return the start of the device-tree string area
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Returns:
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Start offset of string area
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"""
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return fdt_off_dt_strings(self._fdt)
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def off_mem_rsvmap(self):
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"""Return the start of the memory reserve map
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Returns:
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Start offset of memory reserve map
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"""
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return fdt_off_mem_rsvmap(self._fdt)
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def version(self):
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"""Return the version of the device tree
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Returns:
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Version number of the device tree
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"""
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return fdt_version(self._fdt)
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def last_comp_version(self):
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"""Return the last compatible version of the device tree
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Returns:
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Last compatible version number of the device tree
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"""
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return fdt_last_comp_version(self._fdt)
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def boot_cpuid_phys(self):
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"""Return the physical boot CPU ID
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Returns:
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Physical boot CPU ID
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"""
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return fdt_boot_cpuid_phys(self._fdt)
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def size_dt_strings(self):
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"""Return the start of the device-tree string area
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Returns:
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Start offset of string area
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"""
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return fdt_size_dt_strings(self._fdt)
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def size_dt_struct(self):
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"""Return the start of the device-tree struct area
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Returns:
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Start offset of struct area
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"""
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return fdt_size_dt_struct(self._fdt)
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def num_mem_rsv(self, quiet=()):
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"""Return the number of memory reserve-map records
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Returns:
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Number of memory reserve-map records
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"""
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return check_err(fdt_num_mem_rsv(self._fdt), quiet)
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def get_mem_rsv(self, index, quiet=()):
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"""Return the indexed memory reserve-map record
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Args:
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index: Record to return (0=first)
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Returns:
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Number of memory reserve-map records
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"""
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return check_err(fdt_get_mem_rsv(self._fdt, index), quiet)
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def subnode_offset(self, parentoffset, name, quiet=()):
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"""Get the offset of a named subnode
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Args:
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parentoffset: Offset of the parent node to check
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name: Name of the required subnode, e.g. 'subnode@1'
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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The node offset of the found node, if any
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Raises
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FdtException if there is no node with that name, or other error
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"""
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return check_err(fdt_subnode_offset(self._fdt, parentoffset, name),
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quiet)
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def path_offset(self, path, quiet=()):
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"""Get the offset for a given path
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Args:
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path: Path to the required node, e.g. '/node@3/subnode@1'
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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Node offset
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Raises
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FdtException if the path is not valid or not found
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"""
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return check_err(fdt_path_offset(self._fdt, path), quiet)
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def get_name(self, nodeoffset):
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"""Get the name of a node
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Args:
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nodeoffset: Offset of node to check
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Returns:
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Node name
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Raises:
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FdtException on error (e.g. nodeoffset is invalid)
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"""
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return check_err_null(fdt_get_name(self._fdt, nodeoffset))[0]
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def first_property_offset(self, nodeoffset, quiet=()):
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"""Get the offset of the first property in a node offset
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Args:
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nodeoffset: Offset to the node to check
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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Offset of the first property
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Raises
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FdtException if the associated node has no properties, or some
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other error occurred
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"""
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return check_err(fdt_first_property_offset(self._fdt, nodeoffset),
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quiet)
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def next_property_offset(self, prop_offset, quiet=()):
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"""Get the next property in a node
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Args:
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prop_offset: Offset of the previous property
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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Offset of the next property
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Raises:
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FdtException if the associated node has no more properties, or
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some other error occurred
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"""
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return check_err(fdt_next_property_offset(self._fdt, prop_offset),
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quiet)
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def get_property_by_offset(self, prop_offset, quiet=()):
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"""Obtains a property that can be examined
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Args:
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prop_offset: Offset of property (e.g. from first_property_offset())
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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Property object, or None if not found
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Raises:
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FdtException on error (e.g. invalid prop_offset or device
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tree format)
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"""
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pdata = check_err_null(
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fdt_get_property_by_offset(self._fdt, prop_offset), quiet)
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if isinstance(pdata, (int)):
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return pdata
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return Property(pdata[0], pdata[1])
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def getprop(self, nodeoffset, prop_name, quiet=()):
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"""Get a property from a node
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Args:
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nodeoffset: Node offset containing property to get
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prop_name: Name of property to get
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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Value of property as a Property object (which can be used as a
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bytearray/string), or -ve error number. On failure, returns an
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integer error
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Raises:
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FdtError if any error occurs (e.g. the property is not found)
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"""
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pdata = check_err_null(fdt_getprop(self._fdt, nodeoffset, prop_name),
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quiet)
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if isinstance(pdata, (int)):
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return pdata
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return Property(prop_name, bytes(pdata[0]))
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def get_phandle(self, nodeoffset):
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"""Get the phandle of a node
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Args:
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nodeoffset: Node offset to check
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Returns:
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phandle of node, or 0 if the node has no phandle or another error
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occurs
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"""
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return fdt_get_phandle(self._fdt, nodeoffset)
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def get_alias(self, name):
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"""Get the full path referenced by a given alias
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Args:
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name: name of the alias to lookup
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Returns:
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Full path to the node for the alias named 'name', if it exists
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None, if the given alias or the /aliases node does not exist
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"""
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return fdt_get_alias(self._fdt, name)
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def parent_offset(self, nodeoffset, quiet=()):
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"""Get the offset of a node's parent
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Args:
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nodeoffset: Node offset to check
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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The offset of the parent node, if any
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Raises:
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FdtException if no parent found or other error occurs
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"""
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return check_err(fdt_parent_offset(self._fdt, nodeoffset), quiet)
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def node_offset_by_phandle(self, phandle, quiet=()):
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"""Get the offset of a node with the given phandle
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Args:
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phandle: Phandle to search for
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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The offset of node with that phandle, if any
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Raises:
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FdtException if no node found or other error occurs
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"""
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return check_err(fdt_node_offset_by_phandle(self._fdt, phandle), quiet)
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class Fdt(FdtRo):
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"""Device tree class, supporting all operations
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The Fdt object is created is created from a device tree binary file,
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e.g. with something like:
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fdt = Fdt(open("filename.dtb").read())
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Operations can then be performed using the methods in this class. Each
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method xxx(args...) corresponds to a libfdt function fdt_xxx(fdt, args...).
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All methods raise an FdtException if an error occurs. To avoid this
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behaviour a 'quiet' parameter is provided for some functions. This
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defaults to empty, but you can pass a list of errors that you expect.
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If one of these errors occurs, the function will return an error number
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(e.g. -NOTFOUND).
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"""
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def __init__(self, data):
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FdtRo.__init__(self, data)
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@staticmethod
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def create_empty_tree(size, quiet=()):
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"""Create an empty device tree ready for use
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Args:
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size: Size of device tree in bytes
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Returns:
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Fdt object containing the device tree
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"""
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data = bytearray(size)
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err = check_err(fdt_create_empty_tree(data, size), quiet)
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if err:
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return err
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return Fdt(data)
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def resize(self, size, quiet=()):
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"""Move the device tree into a larger or smaller space
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This creates a new device tree of size @size and moves the existing
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device tree contents over to that. It can be used to create more space
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in a device tree. Note that the Fdt object remains the same, but it
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now has a new bytearray holding the contents.
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Args:
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size: Required new size of device tree in bytes
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"""
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fdt = bytearray(size)
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err = check_err(fdt_open_into(self._fdt, fdt, size), quiet)
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if err:
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return err
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self._fdt = fdt
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def pack(self, quiet=()):
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"""Pack the device tree to remove unused space
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This adjusts the tree in place.
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Args:
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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Error code, or 0 if OK
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Raises:
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FdtException if any error occurs
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"""
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err = check_err(fdt_pack(self._fdt), quiet)
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if err:
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return err
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del self._fdt[self.totalsize():]
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return err
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def set_name(self, nodeoffset, name, quiet=()):
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"""Set the name of a node
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Args:
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nodeoffset: Node offset of node to update
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name: New node name (string without \0)
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Returns:
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Error code, or 0 if OK
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Raises:
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FdtException if no parent found or other error occurs
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"""
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if chr(0) in name:
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raise ValueError('Property contains embedded nul characters')
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return check_err(fdt_set_name(self._fdt, nodeoffset, name), quiet)
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def setprop(self, nodeoffset, prop_name, val, quiet=()):
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"""Set the value of a property
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Args:
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nodeoffset: Node offset containing the property to create/update
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prop_name: Name of property
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val: Value to write (string or bytearray)
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quiet: Errors to ignore (empty to raise on all errors)
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Returns:
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Error code, or 0 if OK
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Raises:
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FdtException if no parent found or other error occurs
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"""
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return check_err(fdt_setprop(self._fdt, nodeoffset, prop_name, val,
|
|
len(val)), quiet)
|
|
|
|
def setprop_u32(self, nodeoffset, prop_name, val, quiet=()):
|
|
"""Set the value of a property
|
|
|
|
Args:
|
|
nodeoffset: Node offset containing the property to create/update
|
|
prop_name: Name of property
|
|
val: Value to write (integer)
|
|
quiet: Errors to ignore (empty to raise on all errors)
|
|
|
|
Returns:
|
|
Error code, or 0 if OK
|
|
|
|
Raises:
|
|
FdtException if no parent found or other error occurs
|
|
"""
|
|
return check_err(fdt_setprop_u32(self._fdt, nodeoffset, prop_name, val),
|
|
quiet)
|
|
|
|
def setprop_u64(self, nodeoffset, prop_name, val, quiet=()):
|
|
"""Set the value of a property
|
|
|
|
Args:
|
|
nodeoffset: Node offset containing the property to create/update
|
|
prop_name: Name of property
|
|
val: Value to write (integer)
|
|
quiet: Errors to ignore (empty to raise on all errors)
|
|
|
|
Returns:
|
|
Error code, or 0 if OK
|
|
|
|
Raises:
|
|
FdtException if no parent found or other error occurs
|
|
"""
|
|
return check_err(fdt_setprop_u64(self._fdt, nodeoffset, prop_name, val),
|
|
quiet)
|
|
|
|
def setprop_str(self, nodeoffset, prop_name, val, quiet=()):
|
|
"""Set the string value of a property
|
|
|
|
The property is set to the string, with a nul terminator added
|
|
|
|
Args:
|
|
nodeoffset: Node offset containing the property to create/update
|
|
prop_name: Name of property
|
|
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:
|
|
Error code, or 0 if OK
|
|
|
|
Raises:
|
|
FdtException if no parent found or other error occurs
|
|
"""
|
|
val = val.encode('utf-8') + b'\0'
|
|
return check_err(fdt_setprop(self._fdt, nodeoffset, prop_name,
|
|
val, len(val)), quiet)
|
|
|
|
def delprop(self, nodeoffset, prop_name, quiet=()):
|
|
"""Delete a property from a node
|
|
|
|
Args:
|
|
nodeoffset: Node offset containing property to delete
|
|
prop_name: Name of property to delete
|
|
quiet: Errors to ignore (empty to raise on all errors)
|
|
|
|
Returns:
|
|
Error code, or 0 if OK
|
|
|
|
Raises:
|
|
FdtError if the property does not exist, or another error occurs
|
|
"""
|
|
return check_err(fdt_delprop(self._fdt, nodeoffset, prop_name), quiet)
|
|
|
|
def add_subnode(self, parentoffset, name, quiet=()):
|
|
"""Add a new subnode to a node
|
|
|
|
Args:
|
|
parentoffset: Parent offset to add the subnode to
|
|
name: Name of node to add
|
|
|
|
Returns:
|
|
offset of the node created, or negative error code on failure
|
|
|
|
Raises:
|
|
FdtError if there is not enough space, or another error occurs
|
|
"""
|
|
return check_err(fdt_add_subnode(self._fdt, parentoffset, name), quiet)
|
|
|
|
def del_node(self, nodeoffset, quiet=()):
|
|
"""Delete a node
|
|
|
|
Args:
|
|
nodeoffset: Offset of node to delete
|
|
|
|
Returns:
|
|
Error code, or 0 if OK
|
|
|
|
Raises:
|
|
FdtError if an error occurs
|
|
"""
|
|
return check_err(fdt_del_node(self._fdt, nodeoffset), quiet)
|
|
|
|
|
|
class Property(bytearray):
|
|
"""Holds a device tree property name and value.
|
|
|
|
This holds a copy of a property taken from the device tree. It does not
|
|
reference the device tree, so if anything changes in the device tree,
|
|
a Property object will remain valid.
|
|
|
|
Properties:
|
|
name: Property name
|
|
value: Property value as a bytearray
|
|
"""
|
|
def __init__(self, name, value):
|
|
bytearray.__init__(self, value)
|
|
self.name = name
|
|
|
|
def as_cell(self, fmt):
|
|
return struct.unpack('>' + fmt, self)[0]
|
|
|
|
def as_uint32(self):
|
|
return self.as_cell('L')
|
|
|
|
def as_int32(self):
|
|
return self.as_cell('l')
|
|
|
|
def as_uint64(self):
|
|
return self.as_cell('Q')
|
|
|
|
def as_int64(self):
|
|
return self.as_cell('q')
|
|
|
|
def as_str(self):
|
|
"""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(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 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().
|
|
|
|
The context manager functions can be used to make this a bit easier:
|
|
|
|
# First create the device tree with a node and property:
|
|
sw = FdtSw()
|
|
sw.finish_reservemap()
|
|
with sw.add_node(''):
|
|
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.
|
|
"""
|
|
INC_SIZE = 1024 # Expand size by this much when out of space
|
|
|
|
def __init__(self, size_hint=None):
|
|
"""Create a new FdtSw object
|
|
|
|
Args:
|
|
size_hint: A hint as to the initial size to use
|
|
|
|
Raises:
|
|
ValueError if size_hint is negative
|
|
|
|
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
|
|
|
|
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
|
|
"""
|
|
fdtsw = bytearray(self._fdt)
|
|
check_err(fdt_finish(fdtsw))
|
|
return Fdt(fdtsw)
|
|
|
|
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
|
|
|
|
Raises:
|
|
FdtException on any error
|
|
"""
|
|
fdt = bytearray(size)
|
|
err = check_err(fdt_resize(self._fdt, fdt, size))
|
|
self._fdt = fdt
|
|
|
|
def add_reservemap_entry(self, addr, size):
|
|
"""Add a new memory reserve map entry
|
|
|
|
Once finished adding, you must call finish_reservemap().
|
|
|
|
Args:
|
|
addr: 64-bit start address
|
|
size: 64-bit size
|
|
|
|
Raises:
|
|
FdtException on any error
|
|
"""
|
|
while self.check_space(fdt_add_reservemap_entry(self._fdt, addr,
|
|
size)):
|
|
pass
|
|
|
|
def finish_reservemap(self):
|
|
"""Indicate that there are no more reserve map entries to add
|
|
|
|
Raises:
|
|
FdtException on any error
|
|
"""
|
|
while self.check_space(fdt_finish_reservemap(self._fdt)):
|
|
pass
|
|
|
|
def begin_node(self, name):
|
|
"""Begin a new node
|
|
|
|
Use this before adding properties to the node. Then call end_node() to
|
|
finish it. You can also use the context manager as shown in the FdtSw
|
|
class comment.
|
|
|
|
Args:
|
|
name: Name of node to begin
|
|
|
|
Raises:
|
|
FdtException on any error
|
|
"""
|
|
while self.check_space(fdt_begin_node(self._fdt, name)):
|
|
pass
|
|
|
|
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
|
|
|
|
Args:
|
|
name: Name of property to add
|
|
string: String value of property
|
|
|
|
Raises:
|
|
FdtException on any error
|
|
"""
|
|
while self.check_space(fdt_property_string(self._fdt, name, string)):
|
|
pass
|
|
|
|
def property_u32(self, name, val):
|
|
"""Add a property with a 32-bit value
|
|
|
|
Write a single-cell value to the device tree
|
|
|
|
Args:
|
|
name: Name of property to add
|
|
val: Value of property
|
|
|
|
Raises:
|
|
FdtException on any error
|
|
"""
|
|
while self.check_space(fdt_property_u32(self._fdt, name, val)):
|
|
pass
|
|
|
|
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
|
|
|
|
Args:
|
|
name: Name of property to add
|
|
val: Value of property
|
|
|
|
Raises:
|
|
FdtException on any error
|
|
"""
|
|
while self.check_space(fdt_property_u64(self._fdt, name, val)):
|
|
pass
|
|
|
|
def property_cell(self, name, val):
|
|
"""Add a property with a single-cell value
|
|
|
|
Write a single-cell value to the device tree
|
|
|
|
Args:
|
|
name: Name of property to add
|
|
val: Value of property
|
|
quiet: Errors to ignore (empty to raise on all errors)
|
|
|
|
Raises:
|
|
FdtException on any error
|
|
"""
|
|
while self.check_space(fdt_property_cell(self._fdt, name, val)):
|
|
pass
|
|
|
|
def property(self, name, val):
|
|
"""Add a property
|
|
|
|
Write a new property with the given value to the device tree. The value
|
|
is taken as is and is not nul-terminated
|
|
|
|
Args:
|
|
name: Name of property to add
|
|
val: Value of property
|
|
quiet: Errors to ignore (empty to raise on all errors)
|
|
|
|
Raises:
|
|
FdtException on any error
|
|
"""
|
|
while self.check_space(fdt_property_stub(self._fdt, name, val,
|
|
len(val))):
|
|
pass
|
|
|
|
def end_node(self):
|
|
"""End a node
|
|
|
|
Use this after adding properties to a node to close it off. You can also
|
|
use the context manager as shown in the FdtSw class comment.
|
|
|
|
Args:
|
|
quiet: Errors to ignore (empty to raise on all errors)
|
|
|
|
Raises:
|
|
FdtException on any error
|
|
"""
|
|
while self.check_space(fdt_end_node(self._fdt)):
|
|
pass
|
|
|
|
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
|
|
afterward.
|
|
|
|
Args:
|
|
name: Name of node to add
|
|
"""
|
|
return NodeAdder(self, name)
|
|
|
|
|
|
class NodeAdder():
|
|
"""Class to provide a node context
|
|
|
|
This allows you to add nodes in a more natural way:
|
|
|
|
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, fdtsw, name):
|
|
self._fdt = fdtsw
|
|
self._name = name
|
|
|
|
def __enter__(self):
|
|
self._fdt.begin_node(self._name)
|
|
|
|
def __exit__(self, type, value, traceback):
|
|
self._fdt.end_node()
|
|
%}
|
|
|
|
%rename(fdt_property) fdt_property_func;
|
|
|
|
/*
|
|
* 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"
|
|
|
|
%include "typemaps.i"
|
|
|
|
/* Most functions don't change the device tree, so use a const void * */
|
|
%typemap(in) (const void *)(const void *fdt) {
|
|
if (!PyByteArray_Check($input)) {
|
|
SWIG_exception_fail(SWIG_TypeError, "in method '" "$symname"
|
|
"', argument " "$argnum"" of type '" "$type""'");
|
|
}
|
|
$1 = (void *)PyByteArray_AsString($input);
|
|
fdt = $1;
|
|
fdt = fdt; /* avoid unused variable warning */
|
|
}
|
|
|
|
/* Some functions do change the device tree, so use void * */
|
|
%typemap(in) (void *)(const void *fdt) {
|
|
if (!PyByteArray_Check($input)) {
|
|
SWIG_exception_fail(SWIG_TypeError, "in method '" "$symname"
|
|
"', argument " "$argnum"" of type '" "$type""'");
|
|
}
|
|
$1 = PyByteArray_AsString($input);
|
|
fdt = $1;
|
|
fdt = fdt; /* avoid unused variable warning */
|
|
}
|
|
|
|
/* typemap used for fdt_get_property_by_offset() */
|
|
%typemap(out) (struct fdt_property *) {
|
|
PyObject *buff;
|
|
|
|
if ($1) {
|
|
resultobj = PyString_FromString(
|
|
fdt_string(fdt1, fdt32_to_cpu($1->nameoff)));
|
|
buff = PyByteArray_FromStringAndSize(
|
|
(const char *)($1 + 1), fdt32_to_cpu($1->len));
|
|
resultobj = SWIG_Python_AppendOutput(resultobj, buff);
|
|
}
|
|
}
|
|
|
|
%apply int *OUTPUT { int *lenp };
|
|
|
|
/* typemap used for fdt_getprop() */
|
|
%typemap(out) (const void *) {
|
|
if (!$1)
|
|
$result = Py_None;
|
|
else
|
|
%#if PY_VERSION_HEX >= 0x03000000
|
|
$result = Py_BuildValue("y#", $1, *arg4);
|
|
%#else
|
|
$result = Py_BuildValue("s#", $1, *arg4);
|
|
%#endif
|
|
}
|
|
|
|
/* typemap used for fdt_setprop() */
|
|
%typemap(in) (const void *val) {
|
|
%#if PY_VERSION_HEX >= 0x03000000
|
|
if (!PyBytes_Check($input)) {
|
|
SWIG_exception_fail(SWIG_TypeError, "bytes expected in method '" "$symname"
|
|
"', argument " "$argnum"" of type '" "$type""'");
|
|
}
|
|
$1 = PyBytes_AsString($input);
|
|
%#else
|
|
$1 = PyString_AsString($input); /* char *str */
|
|
%#endif
|
|
}
|
|
|
|
/* typemaps used for fdt_next_node() */
|
|
%typemap(in, numinputs=1) int *depth (int depth) {
|
|
depth = (int) PyInt_AsLong($input);
|
|
$1 = &depth;
|
|
}
|
|
|
|
%typemap(argout) int *depth {
|
|
PyObject *val = Py_BuildValue("i", *arg$argnum);
|
|
resultobj = SWIG_Python_AppendOutput(resultobj, val);
|
|
}
|
|
|
|
%apply int *depth { int *depth };
|
|
|
|
/* typemaps for fdt_get_mem_rsv */
|
|
%typemap(in, numinputs=0) uint64_t * (uint64_t temp) {
|
|
$1 = &temp;
|
|
}
|
|
|
|
%typemap(argout) uint64_t * {
|
|
PyObject *val = PyLong_FromUnsignedLongLong(*arg$argnum);
|
|
if (!result) {
|
|
if (PyTuple_GET_SIZE(resultobj) == 0)
|
|
resultobj = val;
|
|
else
|
|
resultobj = SWIG_Python_AppendOutput(resultobj, val);
|
|
}
|
|
}
|
|
|
|
/* We have both struct fdt_property and a function fdt_property() */
|
|
%warnfilter(302) fdt_property;
|
|
|
|
/* These are macros in the header so have to be redefined here */
|
|
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);
|
|
|
|
/*
|
|
* 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_stub(void *fdt, const char *name, const void *val, int len);
|
|
|
|
%include <../libfdt/libfdt.h>
|