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Diffstat (limited to 'tools/binman/bsection.py')
| -rw-r--r-- | tools/binman/bsection.py | 302 |
1 files changed, 302 insertions, 0 deletions
diff --git a/tools/binman/bsection.py b/tools/binman/bsection.py new file mode 100644 index 0000000000..07c72d34c4 --- /dev/null +++ b/tools/binman/bsection.py @@ -0,0 +1,302 @@ +# SPDX-License-Identifier: GPL-2.0+ +# Copyright (c) 2018 Google, Inc +# Written by Simon Glass <sjg@chromium.org> +# +# Base class for sections (collections of entries) +# + +from __future__ import print_function + +from collections import OrderedDict +import sys + +import fdt_util +import re +import tools + +class Section(object): + """A section which contains multiple entries + + A section represents a collection of entries. There must be one or more + sections in an image. Sections are used to group entries together. + + Attributes: + _node: Node object that contains the section definition in device tree + _size: Section size in bytes, or None if not known yet + _align_size: Section size alignment, or None + _pad_before: Number of bytes before the first entry starts. This + effectively changes the place where entry position 0 starts + _pad_after: Number of bytes after the last entry ends. The last + entry will finish on or before this boundary + _pad_byte: Byte to use to pad the section where there is no entry + _sort: True if entries should be sorted by position, False if they + must be in-order in the device tree description + _skip_at_start: Number of bytes before the first entry starts. These + effectively adjust the starting position of entries. For example, + if _pad_before is 16, then the first entry would start at 16. + An entry with pos = 20 would in fact be written at position 4 + in the image file. + _end_4gb: Indicates that the section ends at the 4GB boundary. This is + used for x86 images, which want to use positions such that a + memory address (like 0xff800000) is the first entry position. + This causes _skip_at_start to be set to the starting memory + address. + _entries: OrderedDict() of entries + """ + def __init__(self, name, node, test=False): + global entry + global Entry + import entry + from entry import Entry + + self._node = node + self._size = None + self._align_size = None + self._pad_before = 0 + self._pad_after = 0 + self._pad_byte = 0 + self._sort = False + self._skip_at_start = 0 + self._end_4gb = False + self._entries = OrderedDict() + if not test: + self._ReadNode() + self._ReadEntries() + + def _ReadNode(self): + """Read properties from the section node""" + self._size = fdt_util.GetInt(self._node, 'size') + self._align_size = fdt_util.GetInt(self._node, 'align-size') + if tools.NotPowerOfTwo(self._align_size): + self._Raise("Alignment size %s must be a power of two" % + self._align_size) + self._pad_before = fdt_util.GetInt(self._node, 'pad-before', 0) + self._pad_after = fdt_util.GetInt(self._node, 'pad-after', 0) + self._pad_byte = fdt_util.GetInt(self._node, 'pad-byte', 0) + self._sort = fdt_util.GetBool(self._node, 'sort-by-pos') + self._end_4gb = fdt_util.GetBool(self._node, 'end-at-4gb') + if self._end_4gb and not self._size: + self._Raise("Section size must be provided when using end-at-4gb") + if self._end_4gb: + self._skip_at_start = 0x100000000 - self._size + + def _ReadEntries(self): + for node in self._node.subnodes: + self._entries[node.name] = Entry.Create(self, node) + + def CheckSize(self): + """Check that the section contents does not exceed its size, etc.""" + contents_size = 0 + for entry in self._entries.values(): + contents_size = max(contents_size, entry.pos + entry.size) + + contents_size -= self._skip_at_start + + size = self._size + if not size: + size = self._pad_before + contents_size + self._pad_after + size = tools.Align(size, self._align_size) + + if self._size and contents_size > self._size: + self._Raise("contents size %#x (%d) exceeds section size %#x (%d)" % + (contents_size, contents_size, self._size, self._size)) + if not self._size: + self._size = size + if self._size != tools.Align(self._size, self._align_size): + self._Raise("Size %#x (%d) does not match align-size %#x (%d)" % + (self._size, self._size, self._align_size, self._align_size)) + return size + + def _Raise(self, msg): + """Raises an error for this section + + Args: + msg: Error message to use in the raise string + Raises: + ValueError() + """ + raise ValueError("Section '%s': %s" % (self._node.path, msg)) + + def GetPath(self): + """Get the path of an image (in the FDT) + + Returns: + Full path of the node for this image + """ + return self._node.path + + def FindEntryType(self, etype): + """Find an entry type in the section + + Args: + etype: Entry type to find + Returns: + entry matching that type, or None if not found + """ + for entry in self._entries.values(): + if entry.etype == etype: + return entry + return None + + def GetEntryContents(self): + """Call ObtainContents() for each entry + + This calls each entry's ObtainContents() a few times until they all + return True. We stop calling an entry's function once it returns + True. This allows the contents of one entry to depend on another. + + After 3 rounds we give up since it's likely an error. + """ + todo = self._entries.values() + for passnum in range(3): + next_todo = [] + for entry in todo: + if not entry.ObtainContents(): + next_todo.append(entry) + todo = next_todo + if not todo: + break + + def _SetEntryPosSize(self, name, pos, size): + """Set the position and size of an entry + + Args: + name: Entry name to update + pos: New position + size: New size + """ + entry = self._entries.get(name) + if not entry: + self._Raise("Unable to set pos/size for unknown entry '%s'" % name) + entry.SetPositionSize(self._skip_at_start + pos, size) + + def GetEntryPositions(self): + """Handle entries that want to set the position/size of other entries + + This calls each entry's GetPositions() method. If it returns a list + of entries to update, it updates them. + """ + for entry in self._entries.values(): + pos_dict = entry.GetPositions() + for name, info in pos_dict.iteritems(): + self._SetEntryPosSize(name, *info) + + def PackEntries(self): + """Pack all entries into the section""" + pos = self._skip_at_start + for entry in self._entries.values(): + pos = entry.Pack(pos) + + def _SortEntries(self): + """Sort entries by position""" + entries = sorted(self._entries.values(), key=lambda entry: entry.pos) + self._entries.clear() + for entry in entries: + self._entries[entry._node.name] = entry + + def CheckEntries(self): + """Check that entries do not overlap or extend outside the section""" + if self._sort: + self._SortEntries() + pos = 0 + prev_name = 'None' + for entry in self._entries.values(): + if (entry.pos < self._skip_at_start or + entry.pos >= self._skip_at_start + self._size): + entry.Raise("Position %#x (%d) is outside the section starting " + "at %#x (%d)" % + (entry.pos, entry.pos, self._skip_at_start, + self._skip_at_start)) + if entry.pos < pos: + entry.Raise("Position %#x (%d) overlaps with previous entry '%s' " + "ending at %#x (%d)" % + (entry.pos, entry.pos, prev_name, pos, pos)) + pos = entry.pos + entry.size + prev_name = entry.GetPath() + + def ProcessEntryContents(self): + """Call the ProcessContents() method for each entry + + This is intended to adjust the contents as needed by the entry type. + """ + for entry in self._entries.values(): + entry.ProcessContents() + + def WriteSymbols(self): + """Write symbol values into binary files for access at run time""" + for entry in self._entries.values(): + entry.WriteSymbols(self) + + def BuildSection(self, fd, base_pos): + """Write the section to a file""" + fd.seek(base_pos) + fd.write(self.GetData()) + + def GetData(self): + """Write the section to a file""" + section_data = chr(self._pad_byte) * self._size + + for entry in self._entries.values(): + data = entry.GetData() + base = self._pad_before + entry.pos - self._skip_at_start + section_data = (section_data[:base] + data + + section_data[base + len(data):]) + return section_data + + def LookupSymbol(self, sym_name, optional, msg): + """Look up a symbol in an ELF file + + Looks up a symbol in an ELF file. Only entry types which come from an + ELF image can be used by this function. + + At present the only entry property supported is pos. + + Args: + sym_name: Symbol name in the ELF file to look up in the format + _binman_<entry>_prop_<property> where <entry> is the name of + the entry and <property> is the property to find (e.g. + _binman_u_boot_prop_pos). As a special case, you can append + _any to <entry> to have it search for any matching entry. E.g. + _binman_u_boot_any_prop_pos will match entries called u-boot, + u-boot-img and u-boot-nodtb) + optional: True if the symbol is optional. If False this function + will raise if the symbol is not found + msg: Message to display if an error occurs + + Returns: + Value that should be assigned to that symbol, or None if it was + optional and not found + + Raises: + ValueError if the symbol is invalid or not found, or references a + property which is not supported + """ + m = re.match(r'^_binman_(\w+)_prop_(\w+)$', sym_name) + if not m: + raise ValueError("%s: Symbol '%s' has invalid format" % + (msg, sym_name)) + entry_name, prop_name = m.groups() + entry_name = entry_name.replace('_', '-') + entry = self._entries.get(entry_name) + if not entry: + if entry_name.endswith('-any'): + root = entry_name[:-4] + for name in self._entries: + if name.startswith(root): + rest = name[len(root):] + if rest in ['', '-img', '-nodtb']: + entry = self._entries[name] + if not entry: + err = ("%s: Entry '%s' not found in list (%s)" % + (msg, entry_name, ','.join(self._entries.keys()))) + if optional: + print('Warning: %s' % err, file=sys.stderr) + return None + raise ValueError(err) + if prop_name == 'pos': + return entry.pos + else: + raise ValueError("%s: No such property '%s'" % (msg, prop_name)) + + def GetEntries(self): + return self._entries |