1234567891011121314151617181920212223242526272829303132333435363738394041424344 |
- # SPDX-License-Identifier: GPL-2.0+
- # Copyright (c) 2016 Google, Inc
- # Written by Simon Glass <sjg@chromium.org>
- #
- # Entry-type module for BSS padding for spl/u-boot-spl.bin. This padding
- # can be added after the SPL binary to ensure that anything concatenated
- # to it will appear to SPL to be at the end of BSS rather than the start.
- #
- from binman import elf
- from binman.entry import Entry
- from binman.etype.blob import Entry_blob
- from patman import tools
- class Entry_u_boot_spl_bss_pad(Entry_blob):
- """U-Boot SPL binary padded with a BSS region
- Properties / Entry arguments:
- None
- This holds the padding added after the SPL binary to cover the BSS (Block
- Started by Symbol) region. This region holds the various variables used by
- SPL. It is set to 0 by SPL when it starts up. If you want to append data to
- the SPL image (such as a device tree file), you must pad out the BSS region
- to avoid the data overlapping with U-Boot variables. This entry is useful in
- that case. It automatically pads out the entry size to cover both the code,
- data and BSS.
- The contents of this entry will a certain number of zero bytes, determined
- by __bss_size
- The ELF file 'spl/u-boot-spl' must also be available for this to work, since
- binman uses that to look up the BSS address.
- """
- def __init__(self, section, etype, node):
- super().__init__(section, etype, node)
- def ObtainContents(self):
- fname = tools.GetInputFilename('spl/u-boot-spl')
- bss_size = elf.GetSymbolAddress(fname, '__bss_size')
- if not bss_size:
- self.Raise('Expected __bss_size symbol in spl/u-boot-spl')
- self.SetContents(tools.GetBytes(0, bss_size))
- return True
|