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):
52 self.section = section
55 self.name = node and node.name or 'none'
58 self.contents_size = 0
60 self.align_size = None
64 self.pos_unset = False
69 def Create(section, node, etype=None):
70 """Create a new entry for a node.
73 section: Image object containing this node
74 node: Node object containing information about the entry to create
75 etype: Entry type to use, or None to work it out (used for tests)
78 A new Entry object of the correct type (a subclass of Entry)
81 etype = fdt_util.GetString(node, 'type', node.name)
83 # Convert something like 'u-boot@0' to 'u_boot' since we are only
84 # interested in the type.
85 module_name = etype.replace('-', '_')
86 if '@' in module_name:
87 module_name = module_name.split('@')[0]
88 module = modules.get(module_name)
90 # Also allow entry-type modules to be brought in from the etype directory.
92 # Import the module if we have not already done so.
95 sys.path.insert(0, os.path.join(our_path, 'etype'))
98 module = importlib.import_module(module_name)
100 module = __import__(module_name)
102 raise ValueError("Unknown entry type '%s' in node '%s'" %
106 modules[module_name] = module
108 # Call its constructor to get the object we want.
109 obj = getattr(module, 'Entry_%s' % module_name)
110 return obj(section, etype, node)
113 """Read entry information from the node
115 This reads all the fields we recognise from the node, ready for use.
117 self.pos = fdt_util.GetInt(self._node, 'pos')
118 self.size = fdt_util.GetInt(self._node, 'size')
119 self.align = fdt_util.GetInt(self._node, 'align')
120 if tools.NotPowerOfTwo(self.align):
121 raise ValueError("Node '%s': Alignment %s must be a power of two" %
122 (self._node.path, self.align))
123 self.pad_before = fdt_util.GetInt(self._node, 'pad-before', 0)
124 self.pad_after = fdt_util.GetInt(self._node, 'pad-after', 0)
125 self.align_size = fdt_util.GetInt(self._node, 'align-size')
126 if tools.NotPowerOfTwo(self.align_size):
127 raise ValueError("Node '%s': Alignment size %s must be a power "
128 "of two" % (self._node.path, self.align_size))
129 self.align_end = fdt_util.GetInt(self._node, 'align-end')
130 self.pos_unset = fdt_util.GetBool(self._node, 'pos-unset')
132 def ObtainContents(self):
133 """Figure out the contents of an entry.
136 True if the contents were found, False if another call is needed
137 after the other entries are processed.
139 # No contents by default: subclasses can implement this
143 """Figure out how to pack the entry into the section
145 Most of the time the entries are not fully specified. There may be
146 an alignment but no size. In that case we take the size from the
147 contents of the entry.
149 If an entry has no hard-coded position, it will be placed at @pos.
151 Once this function is complete, both the position and size of the
155 Current section position pointer
158 New section position pointer (after this entry)
162 self.Raise('No position set with pos-unset: should another '
163 'entry provide this correct position?')
164 self.pos = tools.Align(pos, self.align)
165 needed = self.pad_before + self.contents_size + self.pad_after
166 needed = tools.Align(needed, self.align_size)
170 new_pos = self.pos + size
171 aligned_pos = tools.Align(new_pos, self.align_end)
172 if aligned_pos != new_pos:
173 size = aligned_pos - self.pos
174 new_pos = aligned_pos
179 if self.size < needed:
180 self.Raise("Entry contents size is %#x (%d) but entry size is "
181 "%#x (%d)" % (needed, needed, self.size, self.size))
182 # Check that the alignment is correct. It could be wrong if the
183 # and pos or size values were provided (i.e. not calculated), but
184 # conflict with the provided alignment values
185 if self.size != tools.Align(self.size, self.align_size):
186 self.Raise("Size %#x (%d) does not match align-size %#x (%d)" %
187 (self.size, self.size, self.align_size, self.align_size))
188 if self.pos != tools.Align(self.pos, self.align):
189 self.Raise("Position %#x (%d) does not match align %#x (%d)" %
190 (self.pos, self.pos, self.align, self.align))
194 def Raise(self, msg):
195 """Convenience function to raise an error referencing a node"""
196 raise ValueError("Node '%s': %s" % (self._node.path, msg))
199 """Get the path of a node
202 Full path of the node for this entry
204 return self._node.path
209 def GetPositions(self):
212 def SetPositionSize(self, pos, size):
216 def ProcessContents(self):
219 def WriteSymbols(self, section):
220 """Write symbol values into binary files for access at run time
223 section: Section containing the entry
227 def CheckPosition(self):
228 """Check that the entry positions are correct
230 This is used for entries which have extra position requirements (other
231 than having to be fully inside their section). Sub-classes can implement
232 this function and raise if there is a problem.
236 def WriteMap(self, fd, indent):
237 """Write a map of the entry to a .map file
240 fd: File to write the map to
241 indent: Curent indent level of map (0=none, 1=one level, etc.)
243 print('%s%08x %08x %s' % (' ' * indent, self.pos, self.size,