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    f62fb999
    Fix all linker script to handle all rodata sections · f62fb999
    Trent Piepho authored
    
    A recent gcc added a new unaligned rodata section called '.rodata.str1.1',
    which needs to be added the the linker script.  Instead of just adding this
    one section, we use a wildcard ".rodata*" to get all rodata linker section
    gcc has now and might add in the future.
    
    However, '*(.rodata*)' by itself will result in sub-optimal section
    ordering.  The sections will be sorted by object file, which causes extra
    padding between the unaligned rodata.str.1.1 of one object file and the
    aligned rodata of the next object file.  This is easy to fix by using the
    SORT_BY_ALIGNMENT command.
    
    This patch has not be tested one most of the boards modified.  Some boards
    have a linker script that looks something like this:
    
    *(.text)
    . = ALIGN(16);
    *(.rodata)
    *(.rodata.str1.4)
    *(.eh_frame)
    
    I change this to:
    
    *(.text)
    . = ALIGN(16);
    *(.eh_frame)
    *(SORT_BY_ALIGNMENT(SORT_BY_NAME(.rodata*)))
    
    This means the start of rodata will no longer be 16 bytes aligned.
    However, the boundary between text and rodata/eh_frame is still aligned to
    16 bytes, which is what I think the real purpose of the ALIGN call is.
    
    Signed-off-by: default avatarTrent Piepho <xyzzy@speakeasy.org>
    f62fb999
    History
    Fix all linker script to handle all rodata sections
    Trent Piepho authored
    
    A recent gcc added a new unaligned rodata section called '.rodata.str1.1',
    which needs to be added the the linker script.  Instead of just adding this
    one section, we use a wildcard ".rodata*" to get all rodata linker section
    gcc has now and might add in the future.
    
    However, '*(.rodata*)' by itself will result in sub-optimal section
    ordering.  The sections will be sorted by object file, which causes extra
    padding between the unaligned rodata.str.1.1 of one object file and the
    aligned rodata of the next object file.  This is easy to fix by using the
    SORT_BY_ALIGNMENT command.
    
    This patch has not be tested one most of the boards modified.  Some boards
    have a linker script that looks something like this:
    
    *(.text)
    . = ALIGN(16);
    *(.rodata)
    *(.rodata.str1.4)
    *(.eh_frame)
    
    I change this to:
    
    *(.text)
    . = ALIGN(16);
    *(.eh_frame)
    *(SORT_BY_ALIGNMENT(SORT_BY_NAME(.rodata*)))
    
    This means the start of rodata will no longer be 16 bytes aligned.
    However, the boundary between text and rodata/eh_frame is still aligned to
    16 bytes, which is what I think the real purpose of the ALIGN call is.
    
    Signed-off-by: default avatarTrent Piepho <xyzzy@speakeasy.org>
u-boot.lds 1.39 KiB
/*
 * (C) Copyright 2000
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

OUTPUT_FORMAT("elf32-littlearm", "elf32-littlearm", "elf32-littlearm")
OUTPUT_ARCH(arm)
ENTRY(_start)
SECTIONS
{
	. = 0x00000000;

	. = ALIGN(4);
	.text      :
	{
	  cpu/arm920t/start.o	(.text)
	  *(.text)
	}

	. = ALIGN(4);
	.rodata : { *(SORT_BY_ALIGNMENT(SORT_BY_NAME(.rodata*))) }

	. = ALIGN(4);
	.data : { *(.data) }

	. = ALIGN(4);
	.got : { *(.got) }

	. = .;
	__u_boot_cmd_start = .;
	.u_boot_cmd : { *(.u_boot_cmd) }
	__u_boot_cmd_end = .;

	. = ALIGN(4);
	__bss_start = .;
	.bss (NOLOAD) : { *(.bss) . = ALIGN(4); }
	_end = .;
}