aboutsummaryrefslogtreecommitdiff
path: root/tools/dtoc/src_scan.py
blob: f63c9fc166efac7847b490105ace18450f73c00f (plain)
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
#!/usr/bin/python
# SPDX-License-Identifier: GPL-2.0+
#
# Copyright (C) 2017 Google, Inc
# Written by Simon Glass <sjg@chromium.org>
#

"""Scanning of U-Boot source for drivers and structs

This scans the source tree to find out things about all instances of
U_BOOT_DRIVER(), UCLASS_DRIVER and all struct declarations in header files.

See doc/driver-model/of-plat.rst for more informaiton
"""

import os
import re
import sys


def conv_name_to_c(name):
    """Convert a device-tree name to a C identifier

    This uses multiple replace() calls instead of re.sub() since it is faster
    (400ms for 1m calls versus 1000ms for the 're' version).

    Args:
        name (str): Name to convert
    Return:
        str: String containing the C version of this name
    """
    new = name.replace('@', '_at_')
    new = new.replace('-', '_')
    new = new.replace(',', '_')
    new = new.replace('.', '_')
    return new

def get_compat_name(node):
    """Get the node's list of compatible string as a C identifiers

    Args:
        node (fdt.Node): Node object to check
    Return:
        list of str: List of C identifiers for all the compatible strings
    """
    compat = node.props['compatible'].value
    if not isinstance(compat, list):
        compat = [compat]
    return [conv_name_to_c(c) for c in compat]


class Driver:
    """Information about a driver in U-Boot

    Attributes:
        name: Name of driver. For U_BOOT_DRIVER(x) this is 'x'
    """
    def __init__(self, name):
        self.name = name

    def __eq__(self, other):
        return self.name == other.name

    def __repr__(self):
        return "Driver(name='%s')" % self.name


class Scanner:
    """Scanning of the U-Boot source tree

    Properties:
        _basedir (str): Base directory of U-Boot source code. Defaults to the
            grandparent of this file's directory
        _drivers: Dict of valid driver names found in drivers/
            key: Driver name
            value: Driver for that driver
        _driver_aliases: Dict that holds aliases for driver names
            key: Driver alias declared with
                DM_DRIVER_ALIAS(driver_alias, driver_name)
            value: Driver name declared with U_BOOT_DRIVER(driver_name)
        _warning_disabled: true to disable warnings about driver names not found
        _drivers_additional (list or str): List of additional drivers to use
            during scanning
    """
    def __init__(self, basedir, warning_disabled, drivers_additional):
        """Set up a new Scanner
        """
        if not basedir:
            basedir = sys.argv[0].replace('tools/dtoc/dtoc', '')
            if basedir == '':
                basedir = './'
        self._basedir = basedir
        self._drivers = {}
        self._driver_aliases = {}
        self._drivers_additional = drivers_additional or []
        self._warning_disabled = warning_disabled

    def get_normalized_compat_name(self, node):
        """Get a node's normalized compat name

        Returns a valid driver name by retrieving node's list of compatible
        string as a C identifier and performing a check against _drivers
        and a lookup in driver_aliases printing a warning in case of failure.

        Args:
            node (Node): Node object to check
        Return:
            Tuple:
                Driver name associated with the first compatible string
                List of C identifiers for all the other compatible strings
                    (possibly empty)
                In case of no match found, the return will be the same as
                get_compat_name()
        """
        compat_list_c = get_compat_name(node)

        for compat_c in compat_list_c:
            if not compat_c in self._drivers.keys():
                compat_c = self._driver_aliases.get(compat_c)
                if not compat_c:
                    continue

            aliases_c = compat_list_c
            if compat_c in aliases_c:
                aliases_c.remove(compat_c)
            return compat_c, aliases_c

        if not self._warning_disabled:
            print('WARNING: the driver %s was not found in the driver list'
                  % (compat_list_c[0]))

        return compat_list_c[0], compat_list_c[1:]

    def scan_driver(self, fname):
        """Scan a driver file to build a list of driver names and aliases

        This procedure will populate self._drivers and self._driver_aliases

        Args
            fname: Driver filename to scan
        """
        with open(fname, encoding='utf-8') as inf:
            try:
                buff = inf.read()
            except UnicodeDecodeError:
                # This seems to happen on older Python versions
                print("Skipping file '%s' due to unicode error" % fname)
                return

            # The following re will search for driver names declared as
            # U_BOOT_DRIVER(driver_name)
            drivers = re.findall(r'U_BOOT_DRIVER\((.*)\)', buff)

            for driver in drivers:
                self._drivers[driver] = Driver(driver)

            # The following re will search for driver aliases declared as
            # DM_DRIVER_ALIAS(alias, driver_name)
            driver_aliases = re.findall(
                r'DM_DRIVER_ALIAS\(\s*(\w+)\s*,\s*(\w+)\s*\)',
                buff)

            for alias in driver_aliases: # pragma: no cover
                if len(alias) != 2:
                    continue
                self._driver_aliases[alias[1]] = alias[0]

    def scan_drivers(self):
        """Scan the driver folders to build a list of driver names and aliases

        This procedure will populate self._drivers and self._driver_aliases
        """
        for (dirpath, _, filenames) in os.walk(self._basedir):
            for fname in filenames:
                if not fname.endswith('.c'):
                    continue
                self.scan_driver(dirpath + '/' + fname)

        for fname in self._drivers_additional:
            if not isinstance(fname, str) or len(fname) == 0:
                continue
            if fname[0] == '/':
                self.scan_driver(fname)
            else:
                self.scan_driver(self._basedir + '/' + fname)