1 # SPDX-License-Identifier: GPL-2.0+
2 # Copyright (c) 2016 Google, Inc
4 # Base class for all entries
7 from __future__ import print_function
9 # importlib was introduced in Python 2.7 but there was a report of it not
10 # working in 2.7.12, so we work around this:
11 # http://lists.denx.de/pipermail/u-boot/2016-October/269729.html
16 have_importlib = False
25 our_path = os.path.dirname(os.path.realpath(__file__))
28 """An Entry in the section
30 An entry corresponds to a single node in the device-tree description
31 of the section. Each entry ends up being a part of the final section.
32 Entries can be placed either right next to each other, or with padding
33 between them. The type of the entry determines the data that is in it.
35 This class is not used by itself. All entry objects are subclasses of
39 section: The section containing this entry
40 node: The node that created this entry
41 pos: Absolute position of entry within the section, None if not known
42 size: Entry size in bytes, None if not known
43 contents_size: Size of contents in bytes, 0 by default
44 align: Entry start position alignment, or None
45 align_size: Entry size alignment, or None
46 align_end: Entry end position alignment, or None
47 pad_before: Number of pad bytes before the contents, 0 if none
48 pad_after: Number of pad bytes after the contents, 0 if none
49 data: Contents of entry (string of bytes)
51 def __init__(self, section, etype, node, read_node=True, name_prefix=''):
52 self.section = section
55 self.name = node and (name_prefix + node.name) or 'none'
59 self.contents_size = 0
61 self.align_size = None
65 self.pos_unset = False
70 def Create(section, node, etype=None):
71 """Create a new entry for a node.
74 section: Image object containing this node
75 node: Node object containing information about the entry to create
76 etype: Entry type to use, or None to work it out (used for tests)
79 A new Entry object of the correct type (a subclass of Entry)
82 etype = fdt_util.GetString(node, 'type', node.name)
84 # Convert something like 'u-boot@0' to 'u_boot' since we are only
85 # interested in the type.
86 module_name = etype.replace('-', '_')
87 if '@' in module_name:
88 module_name = module_name.split('@')[0]
89 module = modules.get(module_name)
91 # Also allow entry-type modules to be brought in from the etype directory.
93 # Import the module if we have not already done so.
96 sys.path.insert(0, os.path.join(our_path, 'etype'))
99 module = importlib.import_module(module_name)
101 module = __import__(module_name)
103 raise ValueError("Unknown entry type '%s' in node '%s'" %
107 modules[module_name] = module
109 # Call its constructor to get the object we want.
110 obj = getattr(module, 'Entry_%s' % module_name)
111 return obj(section, etype, node)
114 """Read entry information from the node
116 This reads all the fields we recognise from the node, ready for use.
118 self.pos = fdt_util.GetInt(self._node, 'pos')
119 self.size = fdt_util.GetInt(self._node, 'size')
120 self.align = fdt_util.GetInt(self._node, 'align')
121 if tools.NotPowerOfTwo(self.align):
122 raise ValueError("Node '%s': Alignment %s must be a power of two" %
123 (self._node.path, self.align))
124 self.pad_before = fdt_util.GetInt(self._node, 'pad-before', 0)
125 self.pad_after = fdt_util.GetInt(self._node, 'pad-after', 0)
126 self.align_size = fdt_util.GetInt(self._node, 'align-size')
127 if tools.NotPowerOfTwo(self.align_size):
128 raise ValueError("Node '%s': Alignment size %s must be a power "
129 "of two" % (self._node.path, self.align_size))
130 self.align_end = fdt_util.GetInt(self._node, 'align-end')
131 self.pos_unset = fdt_util.GetBool(self._node, 'pos-unset')
133 def ProcessFdt(self, fdt):
136 def SetPrefix(self, prefix):
137 """Set the name prefix for a node
140 prefix: Prefix to set, or '' to not use a prefix
143 self.name = prefix + self.name
145 def SetContents(self, data):
146 """Set the contents of an entry
148 This sets both the data and content_size properties
151 data: Data to set to the contents (string)
154 self.contents_size = len(self.data)
156 def ProcessContentsUpdate(self, data):
157 """Update the contens of an entry, after the size is fixed
159 This checks that the new data is the same size as the old.
162 data: Data to set to the contents (string)
165 ValueError if the new data size is not the same as the old
167 if len(data) != self.contents_size:
168 self.Raise('Cannot update entry size from %d to %d' %
169 (len(data), self.contents_size))
170 self.SetContents(data)
172 def ObtainContents(self):
173 """Figure out the contents of an entry.
176 True if the contents were found, False if another call is needed
177 after the other entries are processed.
179 # No contents by default: subclasses can implement this
183 """Figure out how to pack the entry into the section
185 Most of the time the entries are not fully specified. There may be
186 an alignment but no size. In that case we take the size from the
187 contents of the entry.
189 If an entry has no hard-coded position, it will be placed at @pos.
191 Once this function is complete, both the position and size of the
195 Current section position pointer
198 New section position pointer (after this entry)
202 self.Raise('No position set with pos-unset: should another '
203 'entry provide this correct position?')
204 self.pos = tools.Align(pos, self.align)
205 needed = self.pad_before + self.contents_size + self.pad_after
206 needed = tools.Align(needed, self.align_size)
210 new_pos = self.pos + size
211 aligned_pos = tools.Align(new_pos, self.align_end)
212 if aligned_pos != new_pos:
213 size = aligned_pos - self.pos
214 new_pos = aligned_pos
219 if self.size < needed:
220 self.Raise("Entry contents size is %#x (%d) but entry size is "
221 "%#x (%d)" % (needed, needed, self.size, self.size))
222 # Check that the alignment is correct. It could be wrong if the
223 # and pos or size values were provided (i.e. not calculated), but
224 # conflict with the provided alignment values
225 if self.size != tools.Align(self.size, self.align_size):
226 self.Raise("Size %#x (%d) does not match align-size %#x (%d)" %
227 (self.size, self.size, self.align_size, self.align_size))
228 if self.pos != tools.Align(self.pos, self.align):
229 self.Raise("Position %#x (%d) does not match align %#x (%d)" %
230 (self.pos, self.pos, self.align, self.align))
234 def Raise(self, msg):
235 """Convenience function to raise an error referencing a node"""
236 raise ValueError("Node '%s': %s" % (self._node.path, msg))
239 """Get the path of a node
242 Full path of the node for this entry
244 return self._node.path
249 def GetPositions(self):
252 def SetPositionSize(self, pos, size):
256 def ProcessContents(self):
259 def WriteSymbols(self, section):
260 """Write symbol values into binary files for access at run time
263 section: Section containing the entry
267 def CheckPosition(self):
268 """Check that the entry positions are correct
270 This is used for entries which have extra position requirements (other
271 than having to be fully inside their section). Sub-classes can implement
272 this function and raise if there is a problem.
276 def WriteMap(self, fd, indent):
277 """Write a map of the entry to a .map file
280 fd: File to write the map to
281 indent: Curent indent level of map (0=none, 1=one level, etc.)
283 print('%s%08x %08x %s' % (' ' * indent, self.pos, self.size,