xref: /openbmc/u-boot/tools/dtoc/fdt_util.py (revision 90c08fa0)
1#!/usr/bin/python
2# SPDX-License-Identifier: GPL-2.0+
3#
4# Copyright (C) 2016 Google, Inc
5# Written by Simon Glass <sjg@chromium.org>
6#
7
8import os
9import struct
10import sys
11import tempfile
12
13import command
14import tools
15
16def fdt32_to_cpu(val):
17    """Convert a device tree cell to an integer
18
19    Args:
20        Value to convert (4-character string representing the cell value)
21
22    Return:
23        A native-endian integer value
24    """
25    if sys.version_info > (3, 0):
26        if isinstance(val, bytes):
27            val = val.decode('utf-8')
28        val = val.encode('raw_unicode_escape')
29    return struct.unpack('>I', val)[0]
30
31def fdt_cells_to_cpu(val, cells):
32    """Convert one or two cells to a long integer
33
34    Args:
35        Value to convert (array of one or more 4-character strings)
36
37    Return:
38        A native-endian long value
39    """
40    if not cells:
41        return 0
42    out = long(fdt32_to_cpu(val[0]))
43    if cells == 2:
44        out = out << 32 | fdt32_to_cpu(val[1])
45    return out
46
47def EnsureCompiled(fname):
48    """Compile an fdt .dts source file into a .dtb binary blob if needed.
49
50    Args:
51        fname: Filename (if .dts it will be compiled). It not it will be
52            left alone
53
54    Returns:
55        Filename of resulting .dtb file
56    """
57    _, ext = os.path.splitext(fname)
58    if ext != '.dts':
59        return fname
60
61    dts_input = tools.GetOutputFilename('source.dts')
62    dtb_output = tools.GetOutputFilename('source.dtb')
63
64    search_paths = [os.path.join(os.getcwd(), 'include')]
65    root, _ = os.path.splitext(fname)
66    args = ['-E', '-P', '-x', 'assembler-with-cpp', '-D__ASSEMBLY__']
67    args += ['-Ulinux']
68    for path in search_paths:
69        args.extend(['-I', path])
70    args += ['-o', dts_input, fname]
71    command.Run('cc', *args)
72
73    # If we don't have a directory, put it in the tools tempdir
74    search_list = []
75    for path in search_paths:
76        search_list.extend(['-i', path])
77    args = ['-I', 'dts', '-o', dtb_output, '-O', 'dtb',
78            '-W', 'no-unit_address_vs_reg']
79    args.extend(search_list)
80    args.append(dts_input)
81    dtc = os.environ.get('DTC') or 'dtc'
82    command.Run(dtc, *args)
83    return dtb_output
84
85def GetInt(node, propname, default=None):
86    prop = node.props.get(propname)
87    if not prop:
88        return default
89    value = fdt32_to_cpu(prop.value)
90    if type(value) == type(list):
91        raise ValueError("Node '%s' property '%' has list value: expecting"
92                         "a single integer" % (node.name, propname))
93    return value
94
95def GetString(node, propname, default=None):
96    prop = node.props.get(propname)
97    if not prop:
98        return default
99    value = prop.value
100    if type(value) == type(list):
101        raise ValueError("Node '%s' property '%' has list value: expecting"
102                         "a single string" % (node.name, propname))
103    return value
104
105def GetBool(node, propname, default=False):
106    if propname in node.props:
107        return True
108    return default
109