#!/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'
fname: Filename where the driver was found
uclass_id: Name of uclass, e.g. 'UCLASS_I2C'
compat: Driver data for each compatible string:
key: Compatible string, e.g. 'rockchip,rk3288-grf'
value: Driver data, e,g, 'ROCKCHIP_SYSCON_GRF', or None
fname: Filename where the driver was found
priv (str): struct name of the priv_auto member, e.g. 'serial_priv'
"""
def __init__(self, name, fname):
self.name = name
self.fname = fname
self.uclass_id = None
self.compat = None
self.priv = ''
def __eq__(self, other):
return (self.name == other.name and
self.uclass_id == other.uclass_id and
self.compat == other.compat and
self.priv == other.priv)
def __repr__(self):
return ("Driver(name='%s', uclass_id='%s', compat=%s, priv=%s)" %
(self.name, self.uclass_id, self.compat, self.priv))
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
_of_match: Dict holding information about compatible strings
key: Name of struct udevice_id variable
value: Dict of compatible info in that variable:
key: Compatible string, e.g. 'rockchip,rk3288-grf'
value: Driver data, e,g, 'ROCKCHIP_SYSCON_GRF', or None
_compat_to_driver: Maps compatible strings to Driver
"""
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
self._of_match = {}
self._compat_to_driver = {}
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:]
@classmethod
def _get_re_for_member(cls, member):
"""_get_re_for_member: Get a compiled regular expression
Args:
member (str): Struct member name, e.g. 'priv_auto'
Returns:
re.Pattern: Compiled regular expression that parses:
.member = sizeof(struct fred),
and returns "fred" as group 1
"""
return re.compile(r'^\s*.%s\s*=\s*sizeof\(struct\s+(.*)\),$' % member)
def _parse_driver(self, fname, buff):
"""Parse a C file to extract driver information contained within
This parses U_BOOT_DRIVER() structs to obtain various pieces of useful
information.
It updates the following members:
_drivers - updated with new Driver records for each driver found
in the file
_of_match - updated with each compatible string found in the file
_compat_to_driver - Maps compatible string to Driver
Args:
fname (str): Filename being parsed (used for warnings)
buff (str): Contents of file
Raises:
ValueError: Compatible variable is mentioned in .of_match in
U_BOOT_DRIVER() but not found in the file
"""
# Dict holding information about compatible strings collected in this
# function so far
# key: Name of struct udevice_id variable
# value: Dict of compatible info in that variable:
# key: Compatible string, e.g. 'rockchip,rk3288-grf'
# value: Driver data, e,g, 'ROCKCHIP_SYSCON_GRF', or None
of_match = {}
# Dict holding driver information collected in this function so far
# key: Driver name (C name as in U_BOOT_DRIVER(xxx))
# value: Driver
drivers = {}
# Collect the driver info
driver = None
re_driver = re.compile(r'U_BOOT_DRIVER\((.*)\)')
# Collect the uclass ID, e.g. 'UCLASS_SPI'
re_id = re.compile(r'\s*\.id\s*=\s*(UCLASS_[A-Z0-9_]+)')
# Collect the compatible string, e.g. 'rockchip,rk3288-grf'
compat = None
re_compat = re.compile(r'{\s*.compatible\s*=\s*"(.*)"\s*'
r'(,\s*.data\s*=\s*(\S*))?\s*},')
# This is a dict of compatible strings that were found:
# key: Compatible string, e.g. 'rockchip,rk3288-grf'
# value: Driver data, e,g, 'ROCKCHIP_SYSCON_GRF', or None
compat_dict = {}
# Holds the var nane of the udevice_id list, e.g.
# 'rk3288_syscon_ids_noc' in
# static const struct udevice_id rk3288_syscon_ids_noc[] = {
ids_name = None
re_ids = re.compile(r'struct udevice_id (.*)\[\]\s*=')
# Matches the references to the udevice_id list
re_of_match = re.compile(
r'\.of_match\s*=\s*(of_match_ptr\()?([a-z0-9_]+)(\))?,')
# Matches the struct name for priv
re_priv = self._get_re_for_member('priv_auto')
prefix = ''
for line in buff.splitlines():
# Handle line continuation
if prefix:
line = prefix + line
prefix = ''
if line.endswith('\\'):
prefix = line[:-1]
continue
driver_match = re_driver.search(line)
# If this line contains U_BOOT_DRIVER()...
if driver:
m_id = re_id.search(line)
m_of_match = re_of_match.search(line)
m_priv = re_priv.match(line)
if m_priv:
driver.priv = m_priv.group(1)
elif m_id:
driver.uclass_id = m_id.group(1)
elif m_of_match:
compat = m_of_match.group(2)
elif '};' in line:
if driver.uclass_id and compat:
if compat not in of_match:
raise ValueError(
"%s: Unknown compatible var '%s' (found: %s)" %
(fname, compat, ','.join(of_match.keys())))
driver.compat = of_match[compat]
# This needs to be deterministic, since a driver may
# have multiple compatible strings pointing to it.
# We record the one earliest in the alphabet so it
# will produce the same result on all machines.
for compat_id in of_match[compat]:
old = self._compat_to_driver.get(compat_id)
if not old or driver.name < old.name:
self._compat_to_driver[compat_id] = driver
drivers[driver.name] = driver
else:
# The driver does not have a uclass or compat string.
# The first is required but the second is not, so just
# ignore this.
pass
driver = None
ids_name = None
compat = None
compat_dict = {}
elif ids_name:
compat_m = re_compat.search(line)
if compat_m:
compat_dict[compat_m.group(1)] = compat_m.group(3)
elif '};' in line:
of_match[ids_name] = compat_dict
ids_name = None
elif driver_match:
driver_name = driver_match.group(1)
driver = Driver(driver_name, fname)
else:
ids_m = re_ids.search(line)
if ids_m:
ids_name = ids_m.group(1)
# Make the updates based on what we found
self._drivers.update(drivers)
self._of_match.update(of_match)
def scan_driver(self, fname):
"""Scan a driver file to build a list of driver names and aliases
It updates the following members:
_drivers - updated with new Driver records for each driver found
in the file
_of_match - updated with each compatible string found in the file
_compat_to_driver - Maps compatible string to Driver
_driver_aliases - Maps alias names to driver name
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
# If this file has any U_BOOT_DRIVER() declarations, process it to
# obtain driver information
if 'U_BOOT_DRIVER' in buff:
self._parse_driver(fname, buff)
# 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)