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 a U-Boot binary with an embedded microcode pointer
6#
7
8import struct
9
10import command
11import elf
12from entry import Entry
13from blob import Entry_blob
14import fdt_util
15import tools
16
17class Entry_u_boot_with_ucode_ptr(Entry_blob):
18    """U-Boot with embedded microcode pointer
19
20    See Entry_u_boot_ucode for full details of the 3 entries involved in this
21    process.
22    """
23    def __init__(self, section, etype, node):
24        Entry_blob.__init__(self, section, etype, node)
25        self.elf_fname = 'u-boot'
26        self.target_pos = None
27
28    def GetDefaultFilename(self):
29        return 'u-boot-nodtb.bin'
30
31    def ProcessFdt(self, fdt):
32        # Figure out where to put the microcode pointer
33        fname = tools.GetInputFilename(self.elf_fname)
34        sym = elf.GetSymbolAddress(fname, '_dt_ucode_base_size')
35        if sym:
36           self.target_pos = sym
37        elif not fdt_util.GetBool(self._node, 'optional-ucode'):
38            self.Raise('Cannot locate _dt_ucode_base_size symbol in u-boot')
39        return True
40
41    def ProcessContents(self):
42        # If the image does not need microcode, there is nothing to do
43        if not self.target_pos:
44            return
45
46        # Get the position of the microcode
47        ucode_entry = self.section.FindEntryType('u-boot-ucode')
48        if not ucode_entry:
49            self.Raise('Cannot find microcode region u-boot-ucode')
50
51        # Check the target pos is in the section. If it is not, then U-Boot is
52        # being linked incorrectly, or is being placed at the wrong position
53        # in the section.
54        #
55        # The section must be set up so that U-Boot is placed at the
56        # flash address to which it is linked. For example, if
57        # CONFIG_SYS_TEXT_BASE is 0xfff00000, and the ROM is 8MB, then
58        # the U-Boot region must start at position 7MB in the section. In this
59        # case the ROM starts at 0xff800000, so the position of the first
60        # entry in the section corresponds to that.
61        if (self.target_pos < self.pos or
62                self.target_pos >= self.pos + self.size):
63            self.Raise('Microcode pointer _dt_ucode_base_size at %08x is '
64                'outside the section ranging from %08x to %08x' %
65                (self.target_pos, self.pos, self.pos + self.size))
66
67        # Get the microcode, either from u-boot-ucode or u-boot-dtb-with-ucode.
68        # If we have left the microcode in the device tree, then it will be
69        # in the former. If we extracted the microcode from the device tree
70        # and collated it in one place, it will be in the latter.
71        if ucode_entry.size:
72            pos, size = ucode_entry.pos, ucode_entry.size
73        else:
74            dtb_entry = self.section.FindEntryType('u-boot-dtb-with-ucode')
75            if not dtb_entry or not dtb_entry.ready:
76                self.Raise('Cannot find microcode region u-boot-dtb-with-ucode')
77            pos = dtb_entry.pos + dtb_entry.ucode_offset
78            size = dtb_entry.ucode_size
79
80        # Write the microcode position and size into the entry
81        pos_and_size = struct.pack('<2L', pos, size)
82        self.target_pos -= self.pos
83        self.ProcessContentsUpdate(self.data[:self.target_pos] + pos_and_size +
84                                   self.data[self.target_pos + 8:])
85