u-boot/arch/arc/lib/relocate.c
Alexey Brodkin 3fb8016360 arc: clean-up init procedure
Intention behind this work was elimination of as much assembly-written
code as it is possible.

In case of ARC we already have relocation fix-up implemented in C so why
don't we use C for U-Boot copying, .bss zeroing etc.

It turned out x86 uses pretty similar approach so we re-used parts of
code in "board_f.c" initially implemented for x86.

Now assembly usage during init is limited to stack- and frame-pointer
setup before and after relocation.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Simon Glass <sjg@chromium.org>
2015-04-03 09:47:49 +03:00

88 lines
2.2 KiB
C

/*
* Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <elf.h>
#include <asm/sections.h>
DECLARE_GLOBAL_DATA_PTR;
int copy_uboot_to_ram(void)
{
size_t len = (size_t)&__image_copy_end - (size_t)&__image_copy_start;
memcpy((void *)gd->relocaddr, (void *)&__image_copy_start, len);
return 0;
}
int clear_bss(void)
{
ulong dst_addr = (ulong)&__bss_start + gd->reloc_off;
size_t len = (size_t)&__bss_end - (size_t)&__bss_start;
memset((void *)dst_addr, 0x00, len);
return 0;
}
/*
* Base functionality is taken from x86 version with added ARC-specifics
*/
int do_elf_reloc_fixups(void)
{
Elf32_Rela *re_src = (Elf32_Rela *)(&__rel_dyn_start);
Elf32_Rela *re_end = (Elf32_Rela *)(&__rel_dyn_end);
Elf32_Addr *offset_ptr_rom, *last_offset = NULL;
Elf32_Addr *offset_ptr_ram;
do {
/* Get the location from the relocation entry */
offset_ptr_rom = (Elf32_Addr *)re_src->r_offset;
/* Check that the location of the relocation is in .text */
if (offset_ptr_rom >= (Elf32_Addr *)&__image_copy_start &&
offset_ptr_rom > last_offset) {
unsigned int val;
/* Switch to the in-RAM version */
offset_ptr_ram = (Elf32_Addr *)((ulong)offset_ptr_rom +
gd->reloc_off);
/*
* Use "memcpy" because target location might be
* 16-bit aligned on ARC so we may need to read
* byte-by-byte. On attempt to read entire word by
* CPU throws an exception
*/
memcpy(&val, offset_ptr_ram, sizeof(int));
#ifdef __LITTLE_ENDIAN__
/* If location in ".text" section swap value */
if ((unsigned int)offset_ptr_rom <
(unsigned int)&__ivt_end)
val = (val << 16) | (val >> 16);
#endif
/* Check that the target points into executable */
if (val >= (unsigned int)&__image_copy_start && val <=
(unsigned int)&__image_copy_end) {
val += gd->reloc_off;
#ifdef __LITTLE_ENDIAN__
/* If location in ".text" section swap value */
if ((unsigned int)offset_ptr_rom <
(unsigned int)&__ivt_end)
val = (val << 16) | (val >> 16);
#endif
memcpy(offset_ptr_ram, &val, sizeof(int));
}
}
last_offset = offset_ptr_rom;
} while (++re_src < re_end);
return 0;
}