tools/binman/etype/u_boot_dtb_with_ucode.py

   1 # SPDX-License-Identifier: GPL-2.0+
   2 # Copyright (c) 2016 Google, Inc
   3 # Written by Simon Glass <sjg@chromium.org>
   4 #
   5 # Entry-type module for U-Boot device tree with the microcode removed
   6 #
   7
   8 import fdt
   9 from entry import Entry
  10 from blob import Entry_blob
  11 import tools
  12
  13 class Entry_u_boot_dtb_with_ucode(Entry_blob):
  14     """A U-Boot device tree file, with the microcode removed
  15
  16     See Entry_u_boot_ucode for full details of the 3 entries involved in this
  17     process.
  18     """
  19     def __init__(self, image, etype, node):
  20         Entry_blob.__init__(self, image, etype, node)
  21         self.ucode_data = ''
  22         self.collate = False
  23         self.ucode_offset = None
  24         self.ucode_size = None
  25
  26     def GetDefaultFilename(self):
  27         return 'u-boot.dtb'
  28
  29     def ObtainContents(self):
  30         Entry_blob.ObtainContents(self)
  31
  32         # If the image does not need microcode, there is nothing to do
  33         ucode_dest_entry = self.image.FindEntryType('u-boot-spl-with-ucode-ptr')
  34         if not ucode_dest_entry or not ucode_dest_entry.target_pos:
  35             ucode_dest_entry = self.image.FindEntryType('u-boot-with-ucode-ptr')
  36         if not ucode_dest_entry or not ucode_dest_entry.target_pos:
  37             return True
  38
  39         # Create a new file to hold the copied device tree
  40         dtb_name = 'u-boot-dtb-with-ucode.dtb'
  41         fname = tools.GetOutputFilename(dtb_name)
  42         with open(fname, 'wb') as fd:
  43             fd.write(self.data)
  44
  45         # Remove the microcode
  46         dtb = fdt.FdtScan(fname)
  47         ucode = dtb.GetNode('/microcode')
  48         if not ucode:
  49             raise self.Raise("No /microcode node found in '%s'" % fname)
  50
  51         # There's no need to collate it (move all microcode into one place)
  52         # if we only have one chunk of microcode.
  53         self.collate = len(ucode.subnodes) > 1
  54         for node in ucode.subnodes:
  55             data_prop = node.props.get('data')
  56             if data_prop:
  57                 self.ucode_data += ''.join(data_prop.bytes)
  58                 if self.collate:
  59                     prop = node.DeleteProp('data')
  60                 else:
  61                     # Find the offset in the device tree of the ucode data
  62                     self.ucode_offset = data_prop.GetOffset() + 12
  63                     self.ucode_size = len(data_prop.bytes)
  64         if self.collate:
  65             dtb.Pack()
  66             dtb.Flush()
  67
  68             # Make this file the contents of this entry
  69             self._pathname = fname
  70             self.ReadContents()
  71         return True