1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
|
#!/usr/bin/python
# SPDX-License-Identifier: GPL-2.0+
#
# Copyright (C) 2016 Google, Inc
# Written by Simon Glass <sjg@chromium.org>
#
# Utility functions for reading from a device tree. Once the upstream pylibfdt
# implementation advances far enough, we should be able to drop these.
import os
import struct
import sys
import tempfile
import command
import tools
def fdt32_to_cpu(val):
"""Convert a device tree cell to an integer
Args:
Value to convert (4-character string representing the cell value)
Return:
A native-endian integer value
"""
return struct.unpack('>I', val)[0]
def fdt_cells_to_cpu(val, cells):
"""Convert one or two cells to a long integer
Args:
Value to convert (array of one or more 4-character strings)
Return:
A native-endian integer value
"""
if not cells:
return 0
out = int(fdt32_to_cpu(val[0]))
if cells == 2:
out = out << 32 | fdt32_to_cpu(val[1])
return out
def EnsureCompiled(fname, tmpdir=None, capture_stderr=False):
"""Compile an fdt .dts source file into a .dtb binary blob if needed.
Args:
fname: Filename (if .dts it will be compiled). It not it will be
left alone
tmpdir: Temporary directory for output files, or None to use the
tools-module output directory
Returns:
Filename of resulting .dtb file
"""
_, ext = os.path.splitext(fname)
if ext != '.dts':
return fname
if tmpdir:
dts_input = os.path.join(tmpdir, 'source.dts')
dtb_output = os.path.join(tmpdir, 'source.dtb')
else:
dts_input = tools.GetOutputFilename('source.dts')
dtb_output = tools.GetOutputFilename('source.dtb')
search_paths = [os.path.join(os.getcwd(), 'include')]
root, _ = os.path.splitext(fname)
args = ['-E', '-P', '-x', 'assembler-with-cpp', '-D__ASSEMBLY__']
args += ['-Ulinux']
for path in search_paths:
args.extend(['-I', path])
args += ['-o', dts_input, fname]
command.Run('cc', *args)
# If we don't have a directory, put it in the tools tempdir
search_list = []
for path in search_paths:
search_list.extend(['-i', path])
args = ['-I', 'dts', '-o', dtb_output, '-O', 'dtb',
'-W', 'no-unit_address_vs_reg']
args.extend(search_list)
args.append(dts_input)
dtc = os.environ.get('DTC') or 'dtc'
command.Run(dtc, *args, capture_stderr=capture_stderr)
return dtb_output
def GetInt(node, propname, default=None):
"""Get an integer from a property
Args:
node: Node object to read from
propname: property name to read
default: Default value to use if the node/property do not exist
Returns:
Integer value read, or default if none
"""
prop = node.props.get(propname)
if not prop:
return default
if isinstance(prop.value, list):
raise ValueError("Node '%s' property '%s' has list value: expecting "
"a single integer" % (node.name, propname))
value = fdt32_to_cpu(prop.value)
return value
def GetString(node, propname, default=None):
"""Get a string from a property
Args:
node: Node object to read from
propname: property name to read
default: Default value to use if the node/property do not exist
Returns:
String value read, or default if none
"""
prop = node.props.get(propname)
if not prop:
return default
value = prop.value
if isinstance(value, list):
raise ValueError("Node '%s' property '%s' has list value: expecting "
"a single string" % (node.name, propname))
return value
def GetBool(node, propname, default=False):
"""Get an boolean from a property
Args:
node: Node object to read from
propname: property name to read
default: Default value to use if the node/property do not exist
Returns:
Boolean value read, or default if none (if you set this to True the
function will always return True)
"""
if propname in node.props:
return True
return default
def GetByte(node, propname, default=None):
"""Get an byte from a property
Args:
node: Node object to read from
propname: property name to read
default: Default value to use if the node/property do not exist
Returns:
Byte value read, or default if none
"""
prop = node.props.get(propname)
if not prop:
return default
value = prop.value
if isinstance(value, list):
raise ValueError("Node '%s' property '%s' has list value: expecting "
"a single byte" % (node.name, propname))
if len(value) != 1:
raise ValueError("Node '%s' property '%s' has length %d, expecting %d" %
(node.name, propname, len(value), 1))
return ord(value[0])
def GetPhandleList(node, propname):
"""Get a list of phandles from a property
Args:
node: Node object to read from
propname: property name to read
Returns:
List of phandles read, each an integer
"""
prop = node.props.get(propname)
if not prop:
return None
value = prop.value
if not isinstance(value, list):
value = [value]
return [fdt32_to_cpu(v) for v in value]
def GetDatatype(node, propname, datatype):
"""Get a value of a given type from a property
Args:
node: Node object to read from
propname: property name to read
datatype: Type to read (str or int)
Returns:
value read, or None if none
Raises:
ValueError if datatype is not str or int
"""
if datatype == str:
return GetString(node, propname)
elif datatype == int:
return GetInt(node, propname)
raise ValueError("fdt_util internal error: Unknown data type '%s'" %
datatype)
|
