1 # SPDX-License-Identifier: GPL-2.0+
2 # Copyright (c) 2018 Google, Inc
3 # Written by Simon Glass <sjg@chromium.org>
5 # Entry-type module for a Flash map, as used by the flashrom SPI flash tool
8 from binman.entry import Entry
9 from binman import fmap_util
10 from patman import tools
11 from patman.tools import ToHexSize
12 from patman import tout
15 class Entry_fmap(Entry):
16 """An entry which contains an Fmap section
18 Properties / Entry arguments:
21 FMAP is a simple format used by flashrom, an open-source utility for
22 reading and writing the SPI flash, typically on x86 CPUs. The format
23 provides flashrom with a list of areas, so it knows what it in the flash.
24 It can then read or write just a single area, instead of the whole flash.
26 The format is defined by the flashrom project, in the file lib/fmap.h -
27 see www.flashrom.org/Flashrom for more information.
29 When used, this entry will be populated with an FMAP which reflects the
30 entries in the current image. Note that any hierarchy is squashed, since
31 FMAP does not support this. Sections are represented as an area appearing
32 before its contents, so that it is possible to reconstruct the hierarchy
33 from the FMAP by using the offset information. This convention does not
34 seem to be documented, but is used in Chromium OS.
36 CBFS entries appear as a single entry, i.e. the sub-entries are ignored.
38 def __init__(self, section, etype, node):
39 super().__init__(section, etype, node)
42 """Build an FMAP from the entries in the current image
47 def _AddEntries(areas, entry):
48 entries = entry.GetEntries()
49 tout.Debug("fmap: Add entry '%s' type '%s' (%s subentries)" %
50 (entry.GetPath(), entry.etype, ToHexSize(entries)))
51 if entries and entry.etype != 'cbfs':
52 # Create an area for the section, which encompasses all entries
54 if entry.image_pos is None:
57 pos = entry.image_pos - entry.GetRootSkipAtStart()
59 # Drop @ symbols in name
60 name = entry.name.replace('@', '')
62 fmap_util.FmapArea(pos, entry.size or 0, name, 0))
63 for subentry in entries.values():
64 _AddEntries(areas, subentry)
68 pos -= entry.section.GetRootSkipAtStart()
69 areas.append(fmap_util.FmapArea(pos or 0, entry.size or 0,
72 entries = self.GetImage().GetEntries()
74 for entry in entries.values():
75 _AddEntries(areas, entry)
76 return fmap_util.EncodeFmap(self.section.GetImageSize() or 0, self.name,
79 def ObtainContents(self):
80 """Obtain a placeholder for the fmap contents"""
81 self.SetContents(self._GetFmap())
84 def ProcessContents(self):
85 return self.ProcessContentsUpdate(self._GetFmap())