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 SetPrefix(self, prefix):
134 """Set the name prefix for a node
137 prefix: Prefix to set, or '' to not use a prefix
140 self.name = prefix + self.name
142 def SetContents(self, data):
143 """Set the contents of an entry
145 This sets both the data and content_size properties
148 data: Data to set to the contents (string)
151 self.contents_size = len(self.data)
153 def ProcessContentsUpdate(self, data):
154 """Update the contens of an entry, after the size is fixed
156 This checks that the new data is the same size as the old.
159 data: Data to set to the contents (string)
162 ValueError if the new data size is not the same as the old
164 if len(data) != self.contents_size:
165 self.Raise('Cannot update entry size from %d to %d' %
166 (len(data), self.contents_size))
167 self.SetContents(data)
169 def ObtainContents(self):
170 """Figure out the contents of an entry.
173 True if the contents were found, False if another call is needed
174 after the other entries are processed.
176 # No contents by default: subclasses can implement this
180 """Figure out how to pack the entry into the section
182 Most of the time the entries are not fully specified. There may be
183 an alignment but no size. In that case we take the size from the
184 contents of the entry.
186 If an entry has no hard-coded position, it will be placed at @pos.
188 Once this function is complete, both the position and size of the
192 Current section position pointer
195 New section position pointer (after this entry)
199 self.Raise('No position set with pos-unset: should another '
200 'entry provide this correct position?')
201 self.pos = tools.Align(pos, self.align)
202 needed = self.pad_before + self.contents_size + self.pad_after
203 needed = tools.Align(needed, self.align_size)
207 new_pos = self.pos + size
208 aligned_pos = tools.Align(new_pos, self.align_end)
209 if aligned_pos != new_pos:
210 size = aligned_pos - self.pos
211 new_pos = aligned_pos
216 if self.size < needed:
217 self.Raise("Entry contents size is %#x (%d) but entry size is "
218 "%#x (%d)" % (needed, needed, self.size, self.size))
219 # Check that the alignment is correct. It could be wrong if the
220 # and pos or size values were provided (i.e. not calculated), but
221 # conflict with the provided alignment values
222 if self.size != tools.Align(self.size, self.align_size):
223 self.Raise("Size %#x (%d) does not match align-size %#x (%d)" %
224 (self.size, self.size, self.align_size, self.align_size))
225 if self.pos != tools.Align(self.pos, self.align):
226 self.Raise("Position %#x (%d) does not match align %#x (%d)" %
227 (self.pos, self.pos, self.align, self.align))
231 def Raise(self, msg):
232 """Convenience function to raise an error referencing a node"""
233 raise ValueError("Node '%s': %s" % (self._node.path, msg))
236 """Get the path of a node
239 Full path of the node for this entry
241 return self._node.path
246 def GetPositions(self):
249 def SetPositionSize(self, pos, size):
253 def ProcessContents(self):
256 def WriteSymbols(self, section):
257 """Write symbol values into binary files for access at run time
260 section: Section containing the entry
264 def CheckPosition(self):
265 """Check that the entry positions are correct
267 This is used for entries which have extra position requirements (other
268 than having to be fully inside their section). Sub-classes can implement
269 this function and raise if there is a problem.
273 def WriteMap(self, fd, indent):
274 """Write a map of the entry to a .map file
277 fd: File to write the map to
278 indent: Curent indent level of map (0=none, 1=one level, etc.)
280 print('%s%08x %08x %s' % (' ' * indent, self.pos, self.size,