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authorTom Rini <trini@konsulko.com>2016-07-15 08:06:22 -0400
committerTom Rini <trini@konsulko.com>2016-07-15 08:06:22 -0400
commitebe621d5fb2f5c15aff50e0610372f2751fd152f (patch)
tree12985b43f1a8500332de8e20274cc2dd26f5a040 /tools
parent36b898b6bea839de7141b65df6ec02a97615c467 (diff)
parent1269625177f120d659f66b18de4b532b16c44561 (diff)
Merge git://git.denx.de/u-boot-dm
Diffstat (limited to 'tools')
-rw-r--r--tools/Makefile14
-rw-r--r--tools/dtoc/.gitignore1
l---------tools/dtoc/dtoc1
-rwxr-xr-xtools/dtoc/dtoc.py394
-rw-r--r--tools/dtoc/fdt.py180
-rw-r--r--tools/dtoc/fdt_fallback.py207
-rw-r--r--tools/dtoc/fdt_util.py86
7 files changed, 883 insertions, 0 deletions
diff --git a/tools/Makefile b/tools/Makefile
index f72294a98a..421414bc15 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -107,6 +107,20 @@ mkimage-objs := $(dumpimage-mkimage-objs) mkimage.o
fit_info-objs := $(dumpimage-mkimage-objs) fit_info.o
fit_check_sign-objs := $(dumpimage-mkimage-objs) fit_check_sign.o
+# Build a libfdt Python module if swig is available
+# Use 'sudo apt-get install swig libpython-dev' to enable this
+hostprogs-$(CONFIG_SPL_OF_PLATDATA) += \
+ $(if $(shell which swig),_libfdt.so)
+_libfdt.so-sharedobjs += $(LIBFDT_OBJS)
+libfdt:
+
+tools/_libfdt.so: $(patsubst %.o,%.c,$(LIBFDT_OBJS)) tools/libfdt_wrap.c
+ python $(srctree)/lib/libfdt/setup.py "$(_hostc_flags)" $^
+ mv _libfdt.so $@
+
+tools/libfdt_wrap.c: $(srctree)/lib/libfdt/libfdt.swig
+ swig -python -o $@ $<
+
# TODO(sjg@chromium.org): Is this correct on Mac OS?
ifneq ($(CONFIG_MX23)$(CONFIG_MX28),)
diff --git a/tools/dtoc/.gitignore b/tools/dtoc/.gitignore
new file mode 100644
index 0000000000..0d20b6487c
--- /dev/null
+++ b/tools/dtoc/.gitignore
@@ -0,0 +1 @@
+*.pyc
diff --git a/tools/dtoc/dtoc b/tools/dtoc/dtoc
new file mode 120000
index 0000000000..896ca44e62
--- /dev/null
+++ b/tools/dtoc/dtoc
@@ -0,0 +1 @@
+dtoc.py \ No newline at end of file
diff --git a/tools/dtoc/dtoc.py b/tools/dtoc/dtoc.py
new file mode 100755
index 0000000000..ec80abe717
--- /dev/null
+++ b/tools/dtoc/dtoc.py
@@ -0,0 +1,394 @@
+#!/usr/bin/python
+#
+# Copyright (C) 2016 Google, Inc
+# Written by Simon Glass <sjg@chromium.org>
+#
+# 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',
+ 'u-boot,dm-pre-reloc',
+]
+
+# 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 <stdbool.h>\n')
+ self.Out('#include <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]
+ 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 <common.h>\n')
+ self.Out('#include <dm.h>\n')
+ self.Out('#include <dt-structs.h>\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('\t.platdata_size\t= sizeof(%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)
diff --git a/tools/dtoc/fdt.py b/tools/dtoc/fdt.py
new file mode 100644
index 0000000000..1d913a925e
--- /dev/null
+++ b/tools/dtoc/fdt.py
@@ -0,0 +1,180 @@
+#!/usr/bin/python
+#
+# Copyright (C) 2016 Google, Inc
+# Written by Simon Glass <sjg@chromium.org>
+#
+# SPDX-License-Identifier: GPL-2.0+
+#
+
+import fdt_util
+import libfdt
+import sys
+
+# This deals with a device tree, presenting it as a list of Node and Prop
+# objects, representing nodes and properties, respectively.
+#
+# This implementation uses a libfdt Python library to access the device tree,
+# so it is fairly efficient.
+
+class Prop:
+ """A device tree property
+
+ Properties:
+ name: Property name (as per the device tree)
+ value: Property value as a string of bytes, or a list of strings of
+ bytes
+ type: Value type
+ """
+ def __init__(self, name, bytes):
+ self.name = name
+ self.value = None
+ if not bytes:
+ self.type = fdt_util.TYPE_BOOL
+ self.value = True
+ return
+ self.type, self.value = fdt_util.BytesToValue(bytes)
+
+ def GetPhandle(self):
+ """Get a (single) phandle value from a property
+
+ Gets the phandle valuie from a property and returns it as an integer
+ """
+ return fdt_util.fdt32_to_cpu(self.value[:4])
+
+ def Widen(self, newprop):
+ """Figure out which property type is more general
+
+ Given a current property and a new property, this function returns the
+ one that is less specific as to type. The less specific property will
+ be ble to represent the data in the more specific property. This is
+ used for things like:
+
+ node1 {
+ compatible = "fred";
+ value = <1>;
+ };
+ node1 {
+ compatible = "fred";
+ value = <1 2>;
+ };
+
+ He we want to use an int array for 'value'. The first property
+ suggests that a single int is enough, but the second one shows that
+ it is not. Calling this function with these two propertes would
+ update the current property to be like the second, since it is less
+ specific.
+ """
+ if newprop.type < self.type:
+ self.type = newprop.type
+
+ if type(newprop.value) == list and type(self.value) != list:
+ self.value = [self.value]
+
+ if type(self.value) == list and len(newprop.value) > len(self.value):
+ val = fdt_util.GetEmpty(self.type)
+ while len(self.value) < len(newprop.value):
+ self.value.append(val)
+
+
+class Node:
+ """A device tree node
+
+ Properties:
+ offset: Integer offset in the device tree
+ name: Device tree node tname
+ path: Full path to node, along with the node name itself
+ _fdt: Device tree object
+ subnodes: A list of subnodes for this node, each a Node object
+ props: A dict of properties for this node, each a Prop object.
+ Keyed by property name
+ """
+ def __init__(self, fdt, offset, name, path):
+ self.offset = offset
+ self.name = name
+ self.path = path
+ self._fdt = fdt
+ self.subnodes = []
+ self.props = {}
+
+ def Scan(self):
+ """Scan a node's properties and subnodes
+
+ This fills in the props and subnodes properties, recursively
+ searching into subnodes so that the entire tree is built.
+ """
+ self.props = self._fdt.GetProps(self.path)
+
+ offset = libfdt.fdt_first_subnode(self._fdt.GetFdt(), self.offset)
+ while offset >= 0:
+ sep = '' if self.path[-1] == '/' else '/'
+ name = libfdt.Name(self._fdt.GetFdt(), offset)
+ path = self.path + sep + name
+ node = Node(self._fdt, offset, name, path)
+ self.subnodes.append(node)
+
+ node.Scan()
+ offset = libfdt.fdt_next_subnode(self._fdt.GetFdt(), offset)
+
+
+class Fdt:
+ """Provides simple access to a flat device tree blob.
+
+ Properties:
+ fname: Filename of fdt
+ _root: Root of device tree (a Node object)
+ """
+
+ def __init__(self, fname):
+ self.fname = fname
+ with open(fname) as fd:
+ self._fdt = fd.read()
+
+ def GetFdt(self):
+ """Get the contents of the FDT
+
+ Returns:
+ The FDT contents as a string of bytes
+ """
+ return self._fdt
+
+ def Scan(self):
+ """Scan a device tree, building up a tree of Node objects
+
+ This fills in the self._root property
+ """
+ self._root = Node(self, 0, '/', '/')
+ self._root.Scan()
+
+ def GetRoot(self):
+ """Get the root Node of the device tree
+
+ Returns:
+ The root Node object
+ """
+ return self._root
+
+ def GetProps(self, node):
+ """Get all properties from a node.
+
+ Args:
+ node: Full path to node name to look in.
+
+ Returns:
+ A dictionary containing all the properties, indexed by node name.
+ The entries are Prop objects.
+
+ Raises:
+ ValueError: if the node does not exist.
+ """
+ offset = libfdt.fdt_path_offset(self._fdt, node)
+ if offset < 0:
+ libfdt.Raise(offset)
+ props_dict = {}
+ poffset = libfdt.fdt_first_property_offset(self._fdt, offset)
+ while poffset >= 0:
+ dprop, plen = libfdt.fdt_get_property_by_offset(self._fdt, poffset)
+ prop = Prop(libfdt.String(self._fdt, dprop.nameoff), libfdt.Data(dprop))
+ props_dict[prop.name] = prop
+
+ poffset = libfdt.fdt_next_property_offset(self._fdt, poffset)
+ return props_dict
diff --git a/tools/dtoc/fdt_fallback.py b/tools/dtoc/fdt_fallback.py
new file mode 100644
index 0000000000..14decf394d
--- /dev/null
+++ b/tools/dtoc/fdt_fallback.py
@@ -0,0 +1,207 @@
+#!/usr/bin/python
+#
+# Copyright (C) 2016 Google, Inc
+# Written by Simon Glass <sjg@chromium.org>
+#
+# SPDX-License-Identifier: GPL-2.0+
+#
+
+import command
+import fdt_util
+import sys
+
+# This deals with a device tree, presenting it as a list of Node and Prop
+# objects, representing nodes and properties, respectively.
+#
+# This implementation uses the fdtget tool to access the device tree, so it
+# is not very efficient for larger trees. The tool is called once for each
+# node and property in the tree.
+
+class Prop:
+ """A device tree property
+
+ Properties:
+ name: Property name (as per the device tree)
+ value: Property value as a string of bytes, or a list of strings of
+ bytes
+ type: Value type
+ """
+ def __init__(self, name, byte_list_str):
+ self.name = name
+ self.value = None
+ if not byte_list_str.strip():
+ self.type = fdt_util.TYPE_BOOL
+ return
+ bytes = [chr(int(byte, 16)) for byte in byte_list_str.strip().split(' ')]
+ self.type, self.value = fdt_util.BytesToValue(''.join(bytes))
+
+ def GetPhandle(self):
+ """Get a (single) phandle value from a property
+
+ Gets the phandle valuie from a property and returns it as an integer
+ """
+ return fdt_util.fdt32_to_cpu(self.value[:4])
+
+ def Widen(self, newprop):
+ """Figure out which property type is more general
+
+ Given a current property and a new property, this function returns the
+ one that is less specific as to type. The less specific property will
+ be ble to represent the data in the more specific property. This is
+ used for things like:
+
+ node1 {
+ compatible = "fred";
+ value = <1>;
+ };
+ node1 {
+ compatible = "fred";
+ value = <1 2>;
+ };
+
+ He we want to use an int array for 'value'. The first property
+ suggests that a single int is enough, but the second one shows that
+ it is not. Calling this function with these two propertes would
+ update the current property to be like the second, since it is less
+ specific.
+ """
+ if newprop.type < self.type:
+ self.type = newprop.type
+
+ if type(newprop.value) == list and type(self.value) != list:
+ self.value = newprop.value
+
+class Node:
+ """A device tree node
+
+ Properties:
+ name: Device tree node tname
+ path: Full path to node, along with the node name itself
+ _fdt: Device tree object
+ subnodes: A list of subnodes for this node, each a Node object
+ props: A dict of properties for this node, each a Prop object.
+ Keyed by property name
+ """
+ def __init__(self, fdt, name, path):
+ self.name = name
+ self.path = path
+ self._fdt = fdt
+ self.subnodes = []
+ self.props = {}
+
+ def Scan(self):
+ """Scan a node's properties and subnodes
+
+ This fills in the props and subnodes properties, recursively
+ searching into subnodes so that the entire tree is built.
+ """
+ for name, byte_list_str in self._fdt.GetProps(self.path).iteritems():
+ prop = Prop(name, byte_list_str)
+ self.props[name] = prop
+
+ for name in self._fdt.GetSubNodes(self.path):
+ sep = '' if self.path[-1] == '/' else '/'
+ path = self.path + sep + name
+ node = Node(self._fdt, name, path)
+ self.subnodes.append(node)
+
+ node.Scan()
+
+
+class Fdt:
+ """Provides simple access to a flat device tree blob.
+
+ Properties:
+ fname: Filename of fdt
+ _root: Root of device tree (a Node object)
+ """
+
+ def __init__(self, fname):
+ self.fname = fname
+
+ def Scan(self):
+ """Scan a device tree, building up a tree of Node objects
+
+ This fills in the self._root property
+ """
+ self._root = Node(self, '/', '/')
+ self._root.Scan()
+
+ def GetRoot(self):
+ """Get the root Node of the device tree
+
+ Returns:
+ The root Node object
+ """
+ return self._root
+
+ def GetSubNodes(self, node):
+ """Returns a list of sub-nodes of a given node
+
+ Args:
+ node: Node name to return children from
+
+ Returns:
+ List of children in the node (each a string node name)
+
+ Raises:
+ CmdError: if the node does not exist.
+ """
+ out = command.Output('fdtget', self.fname, '-l', node)
+ return out.strip().splitlines()
+
+ def GetProps(self, node, convert_dashes=False):
+ """Get all properties from a node
+
+ Args:
+ node: full path to node name to look in
+ convert_dashes: True to convert - to _ in node names
+
+ Returns:
+ A dictionary containing all the properties, indexed by node name.
+ The entries are simply strings - no decoding of lists or numbers
+ is done.
+
+ Raises:
+ CmdError: if the node does not exist.
+ """
+ out = command.Output('fdtget', self.fname, node, '-p')
+ props = out.strip().splitlines()
+ props_dict = {}
+ for prop in props:
+ name = prop
+ if convert_dashes:
+ prop = re.sub('-', '_', prop)
+ props_dict[prop] = self.GetProp(node, name)
+ return props_dict
+
+ def GetProp(self, node, prop, default=None, typespec=None):
+ """Get a property from a device tree.
+
+ This looks up the given node and property, and returns the value as a
+ string,
+
+ If the node or property does not exist, this will return the default
+ value.
+
+ Args:
+ node: Full path to node to look up.
+ prop: Property name to look up.
+ default: Default value to return if nothing is present in the fdt,
+ or None to raise in this case. This will be converted to a
+ string.
+ typespec: Type character to use (None for default, 's' for string)
+
+ Returns:
+ string containing the property value.
+
+ Raises:
+ CmdError: if the property does not exist and no default is provided.
+ """
+ args = [self.fname, node, prop, '-t', 'bx']
+ if default is not None:
+ args += ['-d', str(default)]
+ if typespec is not None:
+ args += ['-t%s' % typespec]
+ out = command.Output('fdtget', *args)
+ return out.strip()
diff --git a/tools/dtoc/fdt_util.py b/tools/dtoc/fdt_util.py
new file mode 100644
index 0000000000..929b524fcf
--- /dev/null
+++ b/tools/dtoc/fdt_util.py
@@ -0,0 +1,86 @@
+#!/usr/bin/python
+#
+# Copyright (C) 2016 Google, Inc
+# Written by Simon Glass <sjg@chromium.org>
+#
+# SPDX-License-Identifier: GPL-2.0+
+#
+
+import struct
+
+# A list of types we support
+(TYPE_BYTE, TYPE_INT, TYPE_STRING, TYPE_BOOL) = range(4)
+
+def BytesToValue(bytes):
+ """Converts a string of bytes into a type and value
+
+ Args:
+ A string containing bytes
+
+ Return:
+ A tuple:
+ Type of data
+ Data, either a single element or a list of elements. Each element
+ is one of:
+ TYPE_STRING: string value from the property
+ TYPE_INT: a byte-swapped integer stored as a 4-byte string
+ TYPE_BYTE: a byte stored as a single-byte string
+ """
+ size = len(bytes)
+ strings = bytes.split('\0')
+ is_string = True
+ count = len(strings) - 1
+ if count > 0 and not strings[-1]:
+ for string in strings[:-1]:
+ if not string:
+ is_string = False
+ break
+ for ch in string:
+ if ch < ' ' or ch > '~':
+ is_string = False
+ break
+ else:
+ is_string = False
+ if is_string:
+ if count == 1:
+ return TYPE_STRING, strings[0]
+ else:
+ return TYPE_STRING, strings[:-1]
+ if size % 4:
+ if size == 1:
+ return TYPE_BYTE, bytes[0]
+ else:
+ return TYPE_BYTE, list(bytes)
+ val = []
+ for i in range(0, size, 4):
+ val.append(bytes[i:i + 4])
+ if size == 4:
+ return TYPE_INT, val[0]
+ else:
+ return TYPE_INT, val
+
+def GetEmpty(type):
+ """Get an empty / zero value of the given type
+
+ Returns:
+ A single value of the given type
+ """
+ if type == TYPE_BYTE:
+ return chr(0)
+ elif type == TYPE_INT:
+ return struct.pack('<I', 0);
+ elif type == TYPE_STRING:
+ return ''
+ else:
+ return True
+
+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]