From 69f2ed7746c8944b2865c3838c36d97908305586 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Mon, 4 Jul 2016 11:58:09 -0600 Subject: dm: Add a tool to generate C code from a device tree This tool can produce C struct definitions and C platform data tables. This is used to support the of-platdata feature. Signed-off-by: Simon Glass --- tools/dtoc/dtoc.py | 391 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 391 insertions(+) create mode 100755 tools/dtoc/dtoc.py (limited to 'tools/dtoc/dtoc.py') diff --git a/tools/dtoc/dtoc.py b/tools/dtoc/dtoc.py new file mode 100755 index 0000000..24f3858 --- /dev/null +++ b/tools/dtoc/dtoc.py @@ -0,0 +1,391 @@ +#!/usr/bin/python +# +# Copyright (C) 2016 Google, Inc +# Written by Simon Glass +# +# SPDX-License-Identifier: GPL-2.0+ +# + +import copy +from optparse import OptionError, OptionParser +import os +import sys + +import fdt_util + +# Bring in the patman libraries +our_path = os.path.dirname(os.path.realpath(__file__)) +sys.path.append(os.path.join(our_path, '../patman')) + +# Bring in either the normal fdt library (which relies on libfdt) or the +# fallback one (which uses fdtget and is slower). Both provide the same +# interfface for this file to use. +try: + from fdt import Fdt + import fdt + have_libfdt = True +except ImportError: + have_libfdt = False + from fdt_fallback import Fdt + import fdt_fallback as fdt + +import struct + +# 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', +] + +# C type declarations for the tyues we support +TYPE_NAMES = { + fdt_util.TYPE_INT: 'fdt32_t', + fdt_util.TYPE_BYTE: 'unsigned char', + fdt_util.TYPE_STRING: 'const char *', + fdt_util.TYPE_BOOL: 'bool', +}; + +STRUCT_PREFIX = 'dtd_' +VAL_PREFIX = 'dtv_' + +def Conv_name_to_c(name): + """Convert a device-tree name to a C identifier + + Args: + name: Name to convert + Return: + String containing the C version of this name + """ + str = name.replace('@', '_at_') + str = str.replace('-', '_') + str = str.replace(',', '_') + str = str.replace('/', '__') + return str + +def TabTo(num_tabs, str): + if len(str) >= num_tabs * 8: + return str + ' ' + return str + '\t' * (num_tabs - len(str) / 8) + +class DtbPlatdata: + """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 + _options: Command-line options + _phandle_node: A dict of nodes indexed by phandle number (1, 2...) + _outfile: The current output file (sys.stdout or a real file) + _lines: Stashed list of output lines for outputting in the future + _phandle_node: A dict of Nodes indexed by phandle (an integer) + """ + def __init__(self, dtb_fname, options): + self._dtb_fname = dtb_fname + self._valid_nodes = None + self._options = options + self._phandle_node = {} + self._outfile = None + self._lines = [] + + def SetupOutput(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, str): + """Output a string to the output file + + Args: + str: String to output + """ + self._outfile.write(str) + + def Buf(self, str): + """Buffer up a string to send later + + Args: + str: String to add to our 'buffer' list + """ + self._lines.append(str) + + def GetBuf(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 GetValue(self, type, 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 type == fdt_util.TYPE_INT: + return '%#x' % fdt_util.fdt32_to_cpu(value) + elif type == fdt_util.TYPE_BYTE: + return '%#x' % ord(value[0]) + elif type == fdt_util.TYPE_STRING: + return '"%s"' % value + elif type == fdt_util.TYPE_BOOL: + return 'true' + + def GetCompatName(self, node): + """Get a node's first compatible string as a C identifier + + Args: + node: Node object to check + Return: + C identifier for the first compatible string + """ + compat = node.props['compatible'].value + if type(compat) == list: + compat = compat[0] + return Conv_name_to_c(compat) + + def ScanDtb(self): + """Scan the device tree to obtain a tree of notes 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(self._dtb_fname) + self.fdt.Scan() + + def ScanTree(self): + """Scan the device tree for useful information + + This fills in the following properties: + _phandle_node: A dict of Nodes indexed by phandle (an integer) + _valid_nodes: A list of nodes we wish to consider include in the + platform data + """ + node_list = [] + self._phandle_node = {} + for node in self.fdt.GetRoot().subnodes: + if 'compatible' in node.props: + status = node.props.get('status') + if (not options.include_disabled and not status or + status.value != 'disabled'): + node_list.append(node) + phandle_prop = node.props.get('phandle') + if phandle_prop: + phandle = phandle_prop.GetPhandle() + self._phandle_node[phandle] = node + + self._valid_nodes = node_list + + def IsPhandle(self, prop): + """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: + True if the object value contains phandles, else False + """ + if prop.name in ['clocks']: + return True + return False + + def ScanStructs(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. + """ + structs = {} + for node in self._valid_nodes: + node_name = self.GetCompatName(node) + fields = {} + + # Get a list of all the valid properties in this node. + for name, prop in node.props.iteritems(): + 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.iteritems(): + 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.GetCompatName(node) + struct = structs[node_name] + for name, prop in node.props.iteritems(): + if name not in PROP_IGNORE_LIST and name[0] != '#': + prop.Widen(struct[name]) + upto += 1 + return structs + + def GenerateStructs(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 + README.of-plat for more information. + """ + self.Out('#include \n') + self.Out('#include \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] + if self.IsPhandle(prop): + # For phandles, include a reference to the target + self.Out('\t%s%s[%d]' % (TabTo(2, 'struct phandle_2_cell'), + Conv_name_to_c(prop.name), + len(prop.value) / 2)) + else: + ptype = TYPE_NAMES[prop.type] + self.Out('\t%s%s' % (TabTo(2, ptype), + Conv_name_to_c(prop.name))) + if type(prop.value) == list: + self.Out('[%d]' % len(prop.value)) + self.Out(';\n') + self.Out('};\n') + + def GenerateTables(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. See the + documentation in README.of-plat for more information. + """ + self.Out('#include \n') + self.Out('#include \n') + self.Out('#include \n') + self.Out('\n') + node_txt_list = [] + for node in self._valid_nodes: + struct_name = self.GetCompatName(node) + var_name = Conv_name_to_c(node.name) + self.Buf('static struct %s%s %s%s = {\n' % + (STRUCT_PREFIX, struct_name, VAL_PREFIX, var_name)) + for pname, prop in node.props.iteritems(): + if pname in PROP_IGNORE_LIST or pname[0] == '#': + continue + ptype = TYPE_NAMES[prop.type] + member_name = Conv_name_to_c(prop.name) + self.Buf('\t%s= ' % TabTo(3, '.' + member_name)) + + # Special handling for lists + if type(prop.value) == list: + self.Buf('{') + vals = [] + # For phandles, output a reference to the platform data + # of the target node. + if self.IsPhandle(prop): + # Process the list as pairs of (phandle, id) + it = iter(prop.value) + for phandle_cell, id_cell in zip(it, it): + phandle = fdt_util.fdt32_to_cpu(phandle_cell) + id = fdt_util.fdt32_to_cpu(id_cell) + target_node = self._phandle_node[phandle] + name = Conv_name_to_c(target_node.name) + vals.append('{&%s%s, %d}' % (VAL_PREFIX, name, id)) + else: + for val in prop.value: + vals.append(self.GetValue(prop.type, val)) + self.Buf(', '.join(vals)) + self.Buf('}') + else: + self.Buf(self.GetValue(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('};\n') + self.Buf('\n') + + # Output phandle target nodes first, since they may be referenced + # by others + if 'phandle' in node.props: + self.Out(''.join(self.GetBuf())) + else: + node_txt_list.append(self.GetBuf()) + + # Output all the nodes which are not phandle targets themselves, but + # may reference them. This avoids the need for forward declarations. + for node_txt in node_txt_list: + self.Out(''.join(node_txt)) + + +if __name__ != "__main__": + pass + +parser = OptionParser() +parser.add_option('-d', '--dtb-file', action='store', + help='Specify the .dtb input file') +parser.add_option('--include-disabled', action='store_true', + help='Include disabled nodes') +parser.add_option('-o', '--output', action='store', default='-', + help='Select output filename') +(options, args) = parser.parse_args() + +if not args: + raise ValueError('Please specify a command: struct, platdata') + +plat = DtbPlatdata(options.dtb_file, options) +plat.ScanDtb() +plat.ScanTree() +plat.SetupOutput(options.output) +structs = plat.ScanStructs() + +for cmd in args[0].split(','): + if cmd == 'struct': + plat.GenerateStructs(structs) + elif cmd == 'platdata': + plat.GenerateTables() + else: + raise ValueError("Unknown command '%s': (use: struct, platdata)" % cmd) -- cgit v1.1 From efefe1221bd779f319b810c5415e577c331edec8 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Mon, 4 Jul 2016 11:58:16 -0600 Subject: dtoc: Ignore the u-boot, dm-pre-reloc property This property is not useful for of-platdata, so omit it. Signed-off-by: Simon Glass --- tools/dtoc/dtoc.py | 1 + 1 file changed, 1 insertion(+) (limited to 'tools/dtoc/dtoc.py') diff --git a/tools/dtoc/dtoc.py b/tools/dtoc/dtoc.py index 24f3858..374ad1c 100755 --- a/tools/dtoc/dtoc.py +++ b/tools/dtoc/dtoc.py @@ -40,6 +40,7 @@ PROP_IGNORE_LIST = [ 'linux,phandle', "status", 'phandle', + 'u-boot,dm-pre-reloc', ] # C type declarations for the tyues we support -- cgit v1.1 From 9fa28190091e59b7c9b9ba32e5a81fa432c485b6 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Mon, 4 Jul 2016 11:58:18 -0600 Subject: dm: core: Expand platdata for of-platdata devices Devices which use of-platdata have their own platdata. However, in many cases the driver will have its own auto-alloced platdata, for use with the device tree. The ofdata_to_platdata() method converts the device tree settings to platdata. With of-platdata we would not normally allocate the platdata since it is provided by the U_BOOT_DEVICE() declaration. However this is inconvenient since the of-platdata struct is closely tied to the device tree properties. It is unlikely to exactly match the platdata needed by the driver. In fact a useful approach is to declare platdata in the driver like this: struct r3288_mmc_platdata { struct dtd_rockchip_rk3288_dw_mshc of_platdata; /* the 'normal' fields go here */ }; In this case we have dt_platadata available, but the normal fields are not present, since ofdata_to_platdata() is never called. In fact driver model doesn't allocate any space for the 'normal' fields, since it sees that there is already platform data attached to the device. To make this easier, adjust driver model to allocate the full size of the struct (i.e. platdata_auto_alloc_size from the driver) and copy in the of-platdata. This means that when the driver's bind() method is called, the of-platdata will be present, followed by zero bytes for the empty 'normal field' portion. A new DM_FLAG_OF_PLATDATA flag is available that indicates that the platdata came from of-platdata. When the allocation/copy happens, the DM_FLAG_ALLOC_PDATA flag will be set as well. The dtoc tool is updated to output the platdata_size field, since U-Boot has no other way of knowing the size of the of-platdata struct. Signed-off-by: Simon Glass --- tools/dtoc/dtoc.py | 2 ++ 1 file changed, 2 insertions(+) (limited to 'tools/dtoc/dtoc.py') diff --git a/tools/dtoc/dtoc.py b/tools/dtoc/dtoc.py index 374ad1c..ec80abe 100755 --- a/tools/dtoc/dtoc.py +++ b/tools/dtoc/dtoc.py @@ -346,6 +346,8 @@ class DtbPlatdata: 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)) self.Buf('};\n') self.Buf('\n') -- cgit v1.1