u-boot/tools/dtoc/dtb_platdata.py
Simon Glass 8a38abfc43 dm: Use driver_info index instead of pointer
At present we use a 'node' pointer in the of-platadata phandle_n_arg
structs. This is a pointer to the struct driver_info for a particular
device, and we can use it to obtain the struct udevice pointer itself.

Since we don't know the struct udevice pointer until it is allocated in
memory, we have to fix up the phandle_n_arg.node at runtime. This is
annoying since it requires that SPL's data is writable and adds a small
amount of extra (generated) code in the dm_populate_phandle_data()
function.

Now that we can find a driver_info by its index, it is easier to put the
index in the phandle_n_arg structures.

Update dtoc to do this, add a new device_get_by_driver_info_idx() to look
up a device by drive_info index and update the tests to match.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-10-29 14:42:18 -06:00

730 lines
26 KiB
Python

#!/usr/bin/python
# SPDX-License-Identifier: GPL-2.0+
#
# Copyright (C) 2017 Google, Inc
# Written by Simon Glass <sjg@chromium.org>
#
"""Device tree to platform data class
This supports converting device tree data to C structures definitions and
static data.
"""
import collections
import copy
import os
import re
import sys
from dtoc import fdt
from dtoc import fdt_util
from patman import tools
# When we see these properties we ignore them - i.e. do not create a structure member
PROP_IGNORE_LIST = [
'#address-cells',
'#gpio-cells',
'#size-cells',
'compatible',
'linux,phandle',
"status",
'phandle',
'u-boot,dm-pre-reloc',
'u-boot,dm-tpl',
'u-boot,dm-spl',
]
# C type declarations for the tyues we support
TYPE_NAMES = {
fdt.TYPE_INT: 'fdt32_t',
fdt.TYPE_BYTE: 'unsigned char',
fdt.TYPE_STRING: 'const char *',
fdt.TYPE_BOOL: 'bool',
fdt.TYPE_INT64: 'fdt64_t',
}
STRUCT_PREFIX = 'dtd_'
VAL_PREFIX = 'dtv_'
# This holds information about a property which includes phandles.
#
# max_args: integer: Maximum number or arguments that any phandle uses (int).
# args: Number of args for each phandle in the property. The total number of
# phandles is len(args). This is a list of integers.
PhandleInfo = collections.namedtuple('PhandleInfo', ['max_args', 'args'])
# Holds a single phandle link, allowing a C struct value to be assigned to point
# to a device
#
# var_node: C variable to assign (e.g. 'dtv_mmc.clocks[0].node')
# dev_name: Name of device to assign to (e.g. 'clock')
PhandleLink = collections.namedtuple('PhandleLink', ['var_node', 'dev_name'])
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: Name to convert
Return:
String containing the C version of this name
"""
new = name.replace('@', '_at_')
new = new.replace('-', '_')
new = new.replace(',', '_')
new = new.replace('.', '_')
return new
def tab_to(num_tabs, line):
"""Append tabs to a line of text to reach a tab stop.
Args:
num_tabs: Tab stop to obtain (0 = column 0, 1 = column 8, etc.)
line: Line of text to append to
Returns:
line with the correct number of tabs appeneded. If the line already
extends past that tab stop then a single space is appended.
"""
if len(line) >= num_tabs * 8:
return line + ' '
return line + '\t' * (num_tabs - len(line) // 8)
def get_value(ftype, value):
"""Get a value as a C expression
For integers this returns a byte-swapped (little-endian) hex string
For bytes this returns a hex string, e.g. 0x12
For strings this returns a literal string enclosed in quotes
For booleans this return 'true'
Args:
type: Data type (fdt_util)
value: Data value, as a string of bytes
"""
if ftype == fdt.TYPE_INT:
return '%#x' % fdt_util.fdt32_to_cpu(value)
elif ftype == fdt.TYPE_BYTE:
return '%#x' % tools.ToByte(value[0])
elif ftype == fdt.TYPE_STRING:
# Handle evil ACPI backslashes by adding another backslash before them.
# So "\\_SB.GPO0" in the device tree effectively stays like that in C
return '"%s"' % value.replace('\\', '\\\\')
elif ftype == fdt.TYPE_BOOL:
return 'true'
elif ftype == fdt.TYPE_INT64:
return '%#x' % value
def get_compat_name(node):
"""Get the node's list of compatible string as a C identifiers
Args:
node: Node object to check
Return:
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 DtbPlatdata(object):
"""Provide a means to convert device tree binary data to platform data
The output of this process is C structures which can be used in space-
constrained encvironments where the ~3KB code overhead of device tree
code is not affordable.
Properties:
_fdt: Fdt object, referencing the device tree
_dtb_fname: Filename of the input device tree binary file
_valid_nodes: A list of Node object with compatible strings. The list
is ordered by conv_name_to_c(node.name)
_include_disabled: true to include nodes marked status = "disabled"
_outfile: The current output file (sys.stdout or a real file)
_warning_disabled: true to disable warnings about driver names not found
_lines: Stashed list of output lines for outputting in the future
_drivers: List of valid driver names found in drivers/
_driver_aliases: Dict that holds aliases for driver names
key: Driver alias declared with
U_BOOT_DRIVER_ALIAS(driver_alias, driver_name)
value: Driver name declared with U_BOOT_DRIVER(driver_name)
_drivers_additional: List of additional drivers to use during scanning
"""
def __init__(self, dtb_fname, include_disabled, warning_disabled,
drivers_additional=[]):
self._fdt = None
self._dtb_fname = dtb_fname
self._valid_nodes = None
self._include_disabled = include_disabled
self._outfile = None
self._warning_disabled = warning_disabled
self._lines = []
self._drivers = []
self._driver_aliases = {}
self._drivers_additional = drivers_additional
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 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:
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 setup_output(self, fname):
"""Set up the output destination
Once this is done, future calls to self.out() will output to this
file.
Args:
fname: Filename to send output to, or '-' for stdout
"""
if fname == '-':
self._outfile = sys.stdout
else:
self._outfile = open(fname, 'w')
def out(self, line):
"""Output a string to the output file
Args:
line: String to output
"""
self._outfile.write(line)
def buf(self, line):
"""Buffer up a string to send later
Args:
line: String to add to our 'buffer' list
"""
self._lines.append(line)
def get_buf(self):
"""Get the contents of the output buffer, and clear it
Returns:
The output buffer, which is then cleared for future use
"""
lines = self._lines
self._lines = []
return lines
def out_header(self):
"""Output a message indicating that this is an auto-generated file"""
self.out('''/*
* DO NOT MODIFY
*
* This file was generated by dtoc from a .dtb (device tree binary) file.
*/
''')
def get_phandle_argc(self, prop, node_name):
"""Check if a node contains phandles
We have no reliable way of detecting whether a node uses a phandle
or not. As an interim measure, use a list of known property names.
Args:
prop: Prop object to check
Return:
Number of argument cells is this is a phandle, else None
"""
if prop.name in ['clocks', 'cd-gpios']:
if not isinstance(prop.value, list):
prop.value = [prop.value]
val = prop.value
i = 0
max_args = 0
args = []
while i < len(val):
phandle = fdt_util.fdt32_to_cpu(val[i])
# If we get to the end of the list, stop. This can happen
# since some nodes have more phandles in the list than others,
# but we allocate enough space for the largest list. So those
# nodes with shorter lists end up with zeroes at the end.
if not phandle:
break
target = self._fdt.phandle_to_node.get(phandle)
if not target:
raise ValueError("Cannot parse '%s' in node '%s'" %
(prop.name, node_name))
cells = None
for prop_name in ['#clock-cells', '#gpio-cells']:
cells = target.props.get(prop_name)
if cells:
break
if not cells:
raise ValueError("Node '%s' has no cells property" %
(target.name))
num_args = fdt_util.fdt32_to_cpu(cells.value)
max_args = max(max_args, num_args)
args.append(num_args)
i += 1 + num_args
return PhandleInfo(max_args, args)
return None
def scan_driver(self, fn):
"""Scan a driver file to build a list of driver names and aliases
This procedure will populate self._drivers and self._driver_aliases
Args
fn: Driver filename to scan
"""
with open(fn, encoding='utf-8') as fd:
try:
buff = fd.read()
except UnicodeDecodeError:
# This seems to happen on older Python versions
print("Skipping file '%s' due to unicode error" % fn)
return
# The following re will search for driver names declared as
# U_BOOT_DRIVER(driver_name)
drivers = re.findall('U_BOOT_DRIVER\((.*)\)', buff)
for driver in drivers:
self._drivers.append(driver)
# The following re will search for driver aliases declared as
# U_BOOT_DRIVER_ALIAS(alias, driver_name)
driver_aliases = re.findall('U_BOOT_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
"""
basedir = sys.argv[0].replace('tools/dtoc/dtoc', '')
if basedir == '':
basedir = './'
for (dirpath, dirnames, filenames) in os.walk(basedir):
for fn in filenames:
if not fn.endswith('.c'):
continue
self.scan_driver(dirpath + '/' + fn)
for fn in self._drivers_additional:
if not isinstance(fn, str) or len(fn) == 0:
continue
if fn[0] == '/':
self.scan_driver(fn)
else:
self.scan_driver(basedir + '/' + fn)
def scan_dtb(self):
"""Scan the device tree to obtain a tree of nodes and properties
Once this is done, self._fdt.GetRoot() can be called to obtain the
device tree root node, and progress from there.
"""
self._fdt = fdt.FdtScan(self._dtb_fname)
def scan_node(self, root, valid_nodes):
"""Scan a node and subnodes to build a tree of node and phandle info
This adds each node to self._valid_nodes.
Args:
root: Root node for scan
valid_nodes: List of Node objects to add to
"""
for node in root.subnodes:
if 'compatible' in node.props:
status = node.props.get('status')
if (not self._include_disabled and not status or
status.value != 'disabled'):
valid_nodes.append(node)
# recurse to handle any subnodes
self.scan_node(node, valid_nodes)
def scan_tree(self):
"""Scan the device tree for useful information
This fills in the following properties:
_valid_nodes: A list of nodes we wish to consider include in the
platform data
"""
valid_nodes = []
self.scan_node(self._fdt.GetRoot(), valid_nodes)
self._valid_nodes = sorted(valid_nodes,
key=lambda x: conv_name_to_c(x.name))
for idx, node in enumerate(self._valid_nodes):
node.idx = idx
@staticmethod
def get_num_cells(node):
"""Get the number of cells in addresses and sizes for this node
Args:
node: Node to check
Returns:
Tuple:
Number of address cells for this node
Number of size cells for this node
"""
parent = node.parent
na, ns = 2, 2
if parent:
na_prop = parent.props.get('#address-cells')
ns_prop = parent.props.get('#size-cells')
if na_prop:
na = fdt_util.fdt32_to_cpu(na_prop.value)
if ns_prop:
ns = fdt_util.fdt32_to_cpu(ns_prop.value)
return na, ns
def scan_reg_sizes(self):
"""Scan for 64-bit 'reg' properties and update the values
This finds 'reg' properties with 64-bit data and converts the value to
an array of 64-values. This allows it to be output in a way that the
C code can read.
"""
for node in self._valid_nodes:
reg = node.props.get('reg')
if not reg:
continue
na, ns = self.get_num_cells(node)
total = na + ns
if reg.type != fdt.TYPE_INT:
raise ValueError("Node '%s' reg property is not an int" %
node.name)
if len(reg.value) % total:
raise ValueError("Node '%s' reg property has %d cells "
'which is not a multiple of na + ns = %d + %d)' %
(node.name, len(reg.value), na, ns))
reg.na = na
reg.ns = ns
if na != 1 or ns != 1:
reg.type = fdt.TYPE_INT64
i = 0
new_value = []
val = reg.value
if not isinstance(val, list):
val = [val]
while i < len(val):
addr = fdt_util.fdt_cells_to_cpu(val[i:], reg.na)
i += na
size = fdt_util.fdt_cells_to_cpu(val[i:], reg.ns)
i += ns
new_value += [addr, size]
reg.value = new_value
def scan_structs(self):
"""Scan the device tree building up the C structures we will use.
Build a dict keyed by C struct name containing a dict of Prop
object for each struct field (keyed by property name). Where the
same struct appears multiple times, try to use the 'widest'
property, i.e. the one with a type which can express all others.
Once the widest property is determined, all other properties are
updated to match that width.
Returns:
dict containing structures:
key (str): Node name, as a C identifier
value: dict containing structure fields:
key (str): Field name
value: Prop object with field information
"""
structs = collections.OrderedDict()
for node in self._valid_nodes:
node_name, _ = self.get_normalized_compat_name(node)
fields = {}
# Get a list of all the valid properties in this node.
for name, prop in node.props.items():
if name not in PROP_IGNORE_LIST and name[0] != '#':
fields[name] = copy.deepcopy(prop)
# If we've seen this node_name before, update the existing struct.
if node_name in structs:
struct = structs[node_name]
for name, prop in fields.items():
oldprop = struct.get(name)
if oldprop:
oldprop.Widen(prop)
else:
struct[name] = prop
# Otherwise store this as a new struct.
else:
structs[node_name] = fields
upto = 0
for node in self._valid_nodes:
node_name, _ = self.get_normalized_compat_name(node)
struct = structs[node_name]
for name, prop in node.props.items():
if name not in PROP_IGNORE_LIST and name[0] != '#':
prop.Widen(struct[name])
upto += 1
return structs
def scan_phandles(self):
"""Figure out what phandles each node uses
We need to be careful when outputing nodes that use phandles since
they must come after the declaration of the phandles in the C file.
Otherwise we get a compiler error since the phandle struct is not yet
declared.
This function adds to each node a list of phandle nodes that the node
depends on. This allows us to output things in the right order.
"""
for node in self._valid_nodes:
node.phandles = set()
for pname, prop in node.props.items():
if pname in PROP_IGNORE_LIST or pname[0] == '#':
continue
info = self.get_phandle_argc(prop, node.name)
if info:
# Process the list as pairs of (phandle, id)
pos = 0
for args in info.args:
phandle_cell = prop.value[pos]
phandle = fdt_util.fdt32_to_cpu(phandle_cell)
target_node = self._fdt.phandle_to_node[phandle]
node.phandles.add(target_node)
pos += 1 + args
def generate_structs(self, structs):
"""Generate struct defintions for the platform data
This writes out the body of a header file consisting of structure
definitions for node in self._valid_nodes. See the documentation in
doc/driver-model/of-plat.rst for more information.
Args:
structs: dict containing structures:
key (str): Node name, as a C identifier
value: dict containing structure fields:
key (str): Field name
value: Prop object with field information
"""
self.out_header()
self.out('#include <stdbool.h>\n')
self.out('#include <linux/libfdt.h>\n')
# Output the struct definition
for name in sorted(structs):
self.out('struct %s%s {\n' % (STRUCT_PREFIX, name))
for pname in sorted(structs[name]):
prop = structs[name][pname]
info = self.get_phandle_argc(prop, structs[name])
if info:
# For phandles, include a reference to the target
struct_name = 'struct phandle_%d_arg' % info.max_args
self.out('\t%s%s[%d]' % (tab_to(2, struct_name),
conv_name_to_c(prop.name),
len(info.args)))
else:
ptype = TYPE_NAMES[prop.type]
self.out('\t%s%s' % (tab_to(2, ptype),
conv_name_to_c(prop.name)))
if isinstance(prop.value, list):
self.out('[%d]' % len(prop.value))
self.out(';\n')
self.out('};\n')
def output_node(self, node):
"""Output the C code for a node
Args:
node: node to output
"""
def _output_list(node, prop):
"""Output the C code for a devicetree property that holds a list
Args:
node (fdt.Node): Node to output
prop (fdt.Prop): Prop to output
"""
self.buf('{')
vals = []
# For phandles, output a reference to the platform data
# of the target node.
info = self.get_phandle_argc(prop, node.name)
if info:
# Process the list as pairs of (phandle, id)
pos = 0
item = 0
for args in info.args:
phandle_cell = prop.value[pos]
phandle = fdt_util.fdt32_to_cpu(phandle_cell)
target_node = self._fdt.phandle_to_node[phandle]
name = conv_name_to_c(target_node.name)
arg_values = []
for i in range(args):
arg_values.append(
str(fdt_util.fdt32_to_cpu(prop.value[pos + 1 + i])))
pos += 1 + args
vals.append('\t{%d, {%s}}' % (target_node.idx,
', '.join(arg_values)))
item += 1
for val in vals:
self.buf('\n\t\t%s,' % val)
else:
for val in prop.value:
vals.append(get_value(prop.type, val))
# Put 8 values per line to avoid very long lines.
for i in range(0, len(vals), 8):
if i:
self.buf(',\n\t\t')
self.buf(', '.join(vals[i:i + 8]))
self.buf('}')
struct_name, _ = self.get_normalized_compat_name(node)
var_name = conv_name_to_c(node.name)
self.buf('/* Node %s index %d */\n' % (node.path, node.idx))
self.buf('static struct %s%s %s%s = {\n' %
(STRUCT_PREFIX, struct_name, VAL_PREFIX, var_name))
for pname in sorted(node.props):
prop = node.props[pname]
if pname in PROP_IGNORE_LIST or pname[0] == '#':
continue
member_name = conv_name_to_c(prop.name)
self.buf('\t%s= ' % tab_to(3, '.' + member_name))
# Special handling for lists
if isinstance(prop.value, list):
_output_list(node, prop)
else:
self.buf(get_value(prop.type, prop.value))
self.buf(',\n')
self.buf('};\n')
# Add a device declaration
self.buf('U_BOOT_DEVICE(%s) = {\n' % var_name)
self.buf('\t.name\t\t= "%s",\n' % struct_name)
self.buf('\t.platdata\t= &%s%s,\n' % (VAL_PREFIX, var_name))
self.buf('\t.platdata_size\t= sizeof(%s%s),\n' % (VAL_PREFIX, var_name))
idx = -1
if node.parent and node.parent in self._valid_nodes:
idx = node.parent.idx
self.buf('\t.parent_idx\t= %d,\n' % idx)
self.buf('};\n')
self.buf('\n')
self.out(''.join(self.get_buf()))
def generate_tables(self):
"""Generate device defintions for the platform data
This writes out C platform data initialisation data and
U_BOOT_DEVICE() declarations for each valid node. Where a node has
multiple compatible strings, a #define is used to make them equivalent.
See the documentation in doc/driver-model/of-plat.rst for more
information.
"""
self.out_header()
self.out('#include <common.h>\n')
self.out('#include <dm.h>\n')
self.out('#include <dt-structs.h>\n')
self.out('\n')
nodes_to_output = list(self._valid_nodes)
# Keep outputing nodes until there is none left
while nodes_to_output:
node = nodes_to_output[0]
# Output all the node's dependencies first
for req_node in node.phandles:
if req_node in nodes_to_output:
self.output_node(req_node)
nodes_to_output.remove(req_node)
self.output_node(node)
nodes_to_output.remove(node)
# Define dm_populate_phandle_data() which will add the linking between
# nodes using DM_GET_DEVICE
# dtv_dmc_at_xxx.clocks[0].node = DM_GET_DEVICE(clock_controller_at_xxx)
self.buf('void dm_populate_phandle_data(void) {\n')
self.buf('}\n')
self.out(''.join(self.get_buf()))
def run_steps(args, dtb_file, include_disabled, output, warning_disabled=False,
drivers_additional=[]):
"""Run all the steps of the dtoc tool
Args:
args: List of non-option arguments provided to the problem
dtb_file: Filename of dtb file to process
include_disabled: True to include disabled nodes
output: Name of output file
"""
if not args:
raise ValueError('Please specify a command: struct, platdata')
plat = DtbPlatdata(dtb_file, include_disabled, warning_disabled, drivers_additional)
plat.scan_drivers()
plat.scan_dtb()
plat.scan_tree()
plat.scan_reg_sizes()
plat.setup_output(output)
structs = plat.scan_structs()
plat.scan_phandles()
for cmd in args[0].split(','):
if cmd == 'struct':
plat.generate_structs(structs)
elif cmd == 'platdata':
plat.generate_tables()
else:
raise ValueError("Unknown command '%s': (use: struct, platdata)" %
cmd)