1# Copyright (c) 2016 Google, Inc
2## Written by Simon Glass <sjg@chromium.org>
3
4# SPDX-License-Identifier:      GPL-2.0+
5#
6# Entry-type module for U-Boot device tree with the microcode removed
7#
8
9import fdt_select
10from entry import Entry
11from blob import Entry_blob
12import tools
13
14class Entry_u_boot_dtb_with_ucode(Entry_blob):
15    """A U-Boot device tree file, with the microcode removed
16
17    See Entry_u_boot_ucode for full details of the 3 entries involved in this
18    process.
19    """
20    def __init__(self, image, etype, node):
21        Entry_blob.__init__(self, image, etype, node)
22        self.ucode_data = ''
23        self.collate = False
24        self.ucode_offset = None
25        self.ucode_size = None
26
27    def GetDefaultFilename(self):
28        return 'u-boot.dtb'
29
30    def ObtainContents(self):
31        Entry_blob.ObtainContents(self)
32
33        # If the image does not need microcode, there is nothing to do
34        ucode_dest_entry = self.image.FindEntryType('u-boot-spl-with-ucode-ptr')
35        if not ucode_dest_entry or not ucode_dest_entry.target_pos:
36            ucode_dest_entry = self.image.FindEntryType('u-boot-with-ucode-ptr')
37        if not ucode_dest_entry or not ucode_dest_entry.target_pos:
38            return True
39
40        # Create a new file to hold the copied device tree
41        dtb_name = 'u-boot-dtb-with-ucode.dtb'
42        fname = tools.GetOutputFilename(dtb_name)
43        with open(fname, 'wb') as fd:
44            fd.write(self.data)
45
46        # Remove the microcode
47        fdt = fdt_select.FdtScan(fname)
48        fdt.Scan()
49        ucode = fdt.GetNode('/microcode')
50        if not ucode:
51            raise self.Raise("No /microcode node found in '%s'" % fname)
52
53        # There's no need to collate it (move all microcode into one place)
54        # if we only have one chunk of microcode.
55        self.collate = len(ucode.subnodes) > 1
56        for node in ucode.subnodes:
57            data_prop = node.props.get('data')
58            if data_prop:
59                self.ucode_data += ''.join(data_prop.bytes)
60                if not self.collate:
61                    poffset = data_prop.GetOffset()
62                    if poffset is None:
63                        # We cannot obtain a property offset. Collate instead.
64                        self.collate = True
65                    else:
66                        # Find the offset in the device tree of the ucode data
67                        self.ucode_offset = poffset + 12
68                        self.ucode_size = len(data_prop.bytes)
69                if self.collate:
70                    prop = node.DeleteProp('data')
71        if self.collate:
72            fdt.Pack()
73            fdt.Flush()
74
75            # Make this file the contents of this entry
76            self._pathname = fname
77            self.ReadContents()
78        return True
79