On Fri, Jul 31, 2015 at 11:31 PM, Simon Glass sjg@chromium.org wrote:
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
Changes in v2:
- Add a comment as to why .hash has to be first in the linker script
- Change 'link script' to 'linker script'
- Drop . = 0x0;
- Fix reference to elf_ia32_efi instead of elf_x86_64_efi
- Merge in Bin's implementation of adding a U-Boot payload with objcopy
- Remove KEEP in the EFI linker script since garbage collection is not enabled
- Rename ImageBase to image_base
- Update based on the elf.h changes
arch/x86/cpu/efi/elf_x86_64_efi.lds | 83 +++++++++++++++++++++++++++++++++++++ arch/x86/lib/efi/reloc_x86_64.c | 66 +++++++++++++++++++++++++++++ 2 files changed, 149 insertions(+) create mode 100644 arch/x86/cpu/efi/elf_x86_64_efi.lds create mode 100644 arch/x86/lib/efi/reloc_x86_64.c
diff --git a/arch/x86/cpu/efi/elf_x86_64_efi.lds b/arch/x86/cpu/efi/elf_x86_64_efi.lds new file mode 100644 index 0000000..667fbe2 --- /dev/null +++ b/arch/x86/cpu/efi/elf_x86_64_efi.lds @@ -0,0 +1,83 @@ +/*
- U-Boot EFI linker script
- SPDX-License-Identifier: bsd-2-clause
- Modified from usr/lib32/elf_x86_64_efi.lds in gnu-efi
- */
+#include <config.h>
+OUTPUT_FORMAT("elf64-x86-64", "elf64-x86-64", "elf64-x86-64") +OUTPUT_ARCH(i386:x86-64) +ENTRY(_start) +SECTIONS +{
image_base = .;.hash : { *(.hash) } /* this MUST come first, EFI expects it */. = ALIGN(4096);.eh_frame : {*(.eh_frame)}. = ALIGN(4096);.text : {*(.text)*(.text.*)*(.gnu.linkonce.t.*)}. = ALIGN(4096);.reloc : {*(.reloc)}. = ALIGN(4096);.data : {*(.rodata*)*(.got.plt)*(.got)*(.data*)*(.sdata)/* the EFI loader doesn't seem to like a .bss section, so we stick* it all into .data: */*(.sbss)*(.scommon)*(.dynbss)*(.bss)*(COMMON)*(.rel.local)/* U-Boot lists and device tree */. = ALIGN(8);*(SORT(.u_boot_list*));. = ALIGN(8);*(.dtb*);}. = ALIGN(4096);.dynamic : { *(.dynamic) }. = ALIGN(4096);.rela : {*(.rela.data*)*(.rela.got)*(.rela.stab)}. = ALIGN(4096);.dynsym : { *(.dynsym) }. = ALIGN(4096);.dynstr : { *(.dynstr) }. = ALIGN(4096);.ignored.reloc : {*(.rela.reloc)*(.eh_frame)*(.note.GNU-stack)}.comment 0 : { *(.comment) }+} diff --git a/arch/x86/lib/efi/reloc_x86_64.c b/arch/x86/lib/efi/reloc_x86_64.c new file mode 100644 index 0000000..5f71f2a --- /dev/null +++ b/arch/x86/lib/efi/reloc_x86_64.c @@ -0,0 +1,66 @@ +/*
- 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;+}
Reviewed-by: Bin Meng bmeng.cn@gmail.com