u-boot/arch/x86/lib/efi/reloc_x86_64.c
Simon Glass 465a67cf52 x86: Add relocation and link script for a 64-bit EFI application
Add a linker script and relocation code for building 64-bit EFI
applications. This can be used for the EFI stub.

Signed-off-by: Simon Glass <sjg@chromium.org>
Improvements to how the payload is built:
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2015-08-05 08:44:06 -06:00

66 lines
1.3 KiB
C

/*
* reloc_x86_64.c - position independent x86_64 ELF shared object relocator
* Copyright (C) 1999 Hewlett-Packard Co.
* Contributed by David Mosberger <davidm@hpl.hp.com>.
* Copyright (C) 2005 Intel Co.
* Contributed by Fenghua Yu <fenghua.yu@intel.com>.
*
* All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <common.h>
#include <efi.h>
#include <elf.h>
#include <asm/elf.h>
efi_status_t _relocate(long ldbase, Elf64_Dyn *dyn, efi_handle_t image,
struct efi_system_table *systab)
{
long relsz = 0, relent = 0;
Elf64_Rel *rel = 0;
unsigned long *addr;
int i;
for (i = 0; dyn[i].d_tag != DT_NULL; ++i) {
switch (dyn[i].d_tag) {
case DT_RELA:
rel = (Elf64_Rel *)
((unsigned long)dyn[i].d_un.d_ptr + ldbase);
break;
case DT_RELASZ:
relsz = dyn[i].d_un.d_val;
break;
case DT_RELAENT:
relent = dyn[i].d_un.d_val;
break;
default:
break;
}
}
if (!rel && relent == 0)
return EFI_SUCCESS;
if (!rel || relent == 0)
return EFI_LOAD_ERROR;
while (relsz > 0) {
/* apply the relocs */
switch (ELF64_R_TYPE(rel->r_info)) {
case R_X86_64_NONE:
break;
case R_X86_64_RELATIVE:
addr = (unsigned long *)(ldbase + rel->r_offset);
*addr += ldbase;
break;
default:
break;
}
rel = (Elf64_Rel *)((char *)rel + relent);
relsz -= relent;
}
return EFI_SUCCESS;
}