1# SPDX-License-Identifier: GPL-2.0+ 2# Copyright (c) 2018 Google, Inc 3# Written by Simon Glass <sjg@chromium.org> 4# 5# Entry-type module for a Flash map, as used by the flashrom SPI flash tool 6# 7 8from binman.entry import Entry 9from binman import fmap_util 10from patman import tools 11from patman.tools import ToHexSize 12from patman import tout 13 14 15class Entry_fmap(Entry): 16 """An entry which contains an Fmap section 17 18 Properties / Entry arguments: 19 None 20 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. 25 26 The format is defined by the flashrom project, in the file lib/fmap.h - 27 see www.flashrom.org/Flashrom for more information. 28 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. 35 36 CBFS entries appear as a single entry, i.e. the sub-entries are ignored. 37 """ 38 def __init__(self, section, etype, node): 39 super().__init__(section, etype, node) 40 41 def _GetFmap(self): 42 """Build an FMAP from the entries in the current image 43 44 Returns: 45 FMAP binary data 46 """ 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 53 # within it 54 if entry.image_pos is None: 55 pos = 0 56 else: 57 pos = entry.image_pos - entry.GetRootSkipAtStart() 58 59 # Drop @ symbols in name 60 name = entry.name.replace('@', '') 61 areas.append( 62 fmap_util.FmapArea(pos, entry.size or 0, name, 0)) 63 for subentry in entries.values(): 64 _AddEntries(areas, subentry) 65 else: 66 pos = entry.image_pos 67 if pos is not None: 68 pos -= entry.section.GetRootSkipAtStart() 69 areas.append(fmap_util.FmapArea(pos or 0, entry.size or 0, 70 entry.name, 0)) 71 72 entries = self.GetImage().GetEntries() 73 areas = [] 74 for entry in entries.values(): 75 _AddEntries(areas, entry) 76 return fmap_util.EncodeFmap(self.section.GetImageSize() or 0, self.name, 77 areas) 78 79 def ObtainContents(self): 80 """Obtain a placeholder for the fmap contents""" 81 self.SetContents(self._GetFmap()) 82 return True 83 84 def ProcessContents(self): 85 return self.ProcessContentsUpdate(self._GetFmap()) 86