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 a U-Boot binary with an embedded microcode pointer
7#
8
9import struct
10
11import command
12import elf
13from entry import Entry
14from blob import Entry_blob
15import fdt_util
16import tools
17
18class Entry_u_boot_with_ucode_ptr(Entry_blob):
19    """U-Boot with embedded microcode pointer
20
21    See Entry_u_boot_ucode for full details of the 3 entries involved in this
22    process.
23    """
24    def __init__(self, image, etype, node):
25        Entry_blob.__init__(self, image, etype, node)
26        self.elf_fname = 'u-boot'
27        self.target_pos = None
28
29    def GetDefaultFilename(self):
30        return 'u-boot-nodtb.bin'
31
32    def ObtainContents(self):
33        # Figure out where to put the microcode pointer
34        fname = tools.GetInputFilename(self.elf_fname)
35        sym = elf.GetSymbolAddress(fname, '_dt_ucode_base_size')
36        if sym:
37           self.target_pos = sym
38        elif not fdt_util.GetBool(self._node, 'optional-ucode'):
39            self.Raise('Cannot locate _dt_ucode_base_size symbol in u-boot')
40
41        return Entry_blob.ObtainContents(self)
42
43    def ProcessContents(self):
44        # If the image does not need microcode, there is nothing to do
45        if not self.target_pos:
46            return
47
48        # Get the position of the microcode
49        ucode_entry = self.image.FindEntryType('u-boot-ucode')
50        if not ucode_entry:
51            self.Raise('Cannot find microcode region u-boot-ucode')
52
53        # Check the target pos is in the image. If it is not, then U-Boot is
54        # being linked incorrectly, or is being placed at the wrong position
55        # in the image.
56        #
57        # The image must be set up so that U-Boot is placed at the
58        # flash address to which it is linked. For example, if
59        # CONFIG_SYS_TEXT_BASE is 0xfff00000, and the ROM is 8MB, then
60        # the U-Boot region must start at position 7MB in the image. In this
61        # case the ROM starts at 0xff800000, so the position of the first
62        # entry in the image corresponds to that.
63        if (self.target_pos < self.pos or
64                self.target_pos >= self.pos + self.size):
65            self.Raise('Microcode pointer _dt_ucode_base_size at %08x is '
66                'outside the image ranging from %08x to %08x' %
67                (self.target_pos, self.pos, self.pos + self.size))
68
69        # Get the microcode, either from u-boot-ucode or u-boot-dtb-with-ucode.
70        # If we have left the microcode in the device tree, then it will be
71        # in the former. If we extracted the microcode from the device tree
72        # and collated it in one place, it will be in the latter.
73        if ucode_entry.size:
74            pos, size = ucode_entry.pos, ucode_entry.size
75        else:
76            dtb_entry = self.image.FindEntryType('u-boot-dtb-with-ucode')
77            if not dtb_entry:
78                self.Raise('Cannot find microcode region u-boot-dtb-with-ucode')
79            pos = dtb_entry.pos + dtb_entry.ucode_offset
80            size = dtb_entry.ucode_size
81
82        # Write the microcode position and size into the entry
83        pos_and_size = struct.pack('<2L', pos, size)
84        self.target_pos -= self.pos
85        self.data = (self.data[:self.target_pos] + pos_and_size +
86                     self.data[self.target_pos + 8:])
87