mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-08-25 19:38:52 +09:00
![Peter Tyser](/assets/img/avatar_default.png)
When U-Boot is relocated from flash to RAM pointers are modified accordingly. However, pointers initialzed with NULL values should not be modified so that they maintain their intended NULL value. If the BSS segment is linked at address 0 its address will not be updated as necessary during relocation. This is a temporary workaround. The end goal is to add support to U-Boot to dynamically locate the BSS at an arbitrary address at runtime. When the ability to fixup the BSS inteligently is added, this workaround can be removed and the 85xx link script can put the BSS at a fixed address at link time. Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
158 lines
3.7 KiB
Plaintext
158 lines
3.7 KiB
Plaintext
/*
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* Copyright 2007-2009 Freescale Semiconductor, Inc.
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*
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* See file CREDITS for list of people who contributed to this
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* project.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of
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* the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
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* MA 02111-1307 USA
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*/
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#ifndef RESET_VECTOR_ADDRESS
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#define RESET_VECTOR_ADDRESS 0xfffffffc
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#endif
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OUTPUT_ARCH(powerpc)
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/* Do we need any of these for elf?
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__DYNAMIC = 0; */
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PHDRS
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{
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text PT_LOAD;
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bss PT_LOAD;
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}
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SECTIONS
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{
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/* Read-only sections, merged into text segment: */
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. = + SIZEOF_HEADERS;
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.interp : { *(.interp) }
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.hash : { *(.hash) }
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.dynsym : { *(.dynsym) }
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.dynstr : { *(.dynstr) }
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.rel.text : { *(.rel.text) }
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.rela.text : { *(.rela.text) }
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.rel.data : { *(.rel.data) }
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.rela.data : { *(.rela.data) }
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.rel.rodata : { *(.rel.rodata) }
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.rela.rodata : { *(.rela.rodata) }
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.rel.got : { *(.rel.got) }
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.rela.got : { *(.rela.got) }
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.rel.ctors : { *(.rel.ctors) }
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.rela.ctors : { *(.rela.ctors) }
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.rel.dtors : { *(.rel.dtors) }
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.rela.dtors : { *(.rela.dtors) }
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.rel.bss : { *(.rel.bss) }
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.rela.bss : { *(.rela.bss) }
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.rel.plt : { *(.rel.plt) }
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.rela.plt : { *(.rela.plt) }
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.init : { *(.init) }
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.plt : { *(.plt) }
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.text :
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{
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*(.text)
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*(.got1)
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} :text
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_etext = .;
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PROVIDE (etext = .);
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.rodata :
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{
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*(.eh_frame)
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*(SORT_BY_ALIGNMENT(SORT_BY_NAME(.rodata*)))
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} :text
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.fini : { *(.fini) } =0
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.ctors : { *(.ctors) }
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.dtors : { *(.dtors) }
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/* Read-write section, merged into data segment: */
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. = (. + 0x00FF) & 0xFFFFFF00;
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_erotext = .;
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PROVIDE (erotext = .);
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.reloc :
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{
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*(.got)
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_GOT2_TABLE_ = .;
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*(.got2)
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_FIXUP_TABLE_ = .;
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*(.fixup)
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}
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__got2_entries = (_FIXUP_TABLE_ - _GOT2_TABLE_) >> 2;
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__fixup_entries = (. - _FIXUP_TABLE_) >> 2;
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.data :
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{
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*(.data)
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*(.data1)
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*(.sdata)
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*(.sdata2)
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*(.dynamic)
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CONSTRUCTORS
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}
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_edata = .;
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PROVIDE (edata = .);
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. = .;
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__u_boot_cmd_start = .;
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.u_boot_cmd : { *(.u_boot_cmd) }
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__u_boot_cmd_end = .;
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. = .;
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__start___ex_table = .;
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__ex_table : { *(__ex_table) }
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__stop___ex_table = .;
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. = ALIGN(256);
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__init_begin = .;
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.text.init : { *(.text.init) }
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.data.init : { *(.data.init) }
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. = ALIGN(256);
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__init_end = .;
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.bootpg RESET_VECTOR_ADDRESS - 0xffc :
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{
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cpu/mpc85xx/start.o (.bootpg)
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} :text = 0xffff
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.resetvec RESET_VECTOR_ADDRESS :
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{
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*(.resetvec)
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} :text = 0xffff
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. = RESET_VECTOR_ADDRESS + 0x4;
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/*
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* Make sure that the bss segment isn't linked at 0x0, otherwise its
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* address won't be updated during relocation fixups. Note that
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* this is a temporary fix. Code to dynamically the fixup the bss
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* location will be added in the future. When the bss relocation
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* fixup code is present this workaround should be removed.
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*/
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#if (RESET_VECTOR_ADDRESS == 0xfffffffc)
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. |= 0x10;
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#endif
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__bss_start = .;
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.bss (NOLOAD) :
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{
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*(.sbss) *(.scommon)
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*(.dynbss)
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*(.bss)
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*(COMMON)
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} :bss
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. = ALIGN(4);
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_end = . ;
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PROVIDE (end = .);
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}
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