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x86: use EFI calling convention for efi_main on x86_64

UEFI specifies the calling convention used in Microsoft compilers;
first arguments of a function are passed in (%rcx, %rdx, %r8, %r9).

All other compilers use System V ABI by default, passing first integer
arguments of a function in (%rdi, %rsi, %rdx, %rcx, %r8, %r9).

These ABI also specify different sets of registers that must be preserved
across function calls (callee-saved).

GCC allows using the Microsoft calling convention by adding the ms_abi
attribute to a function declaration.

Current EFI implementation in U-Boot specifies EFIAPI for efi_main()
in the test apps but uses default calling convention in lib/efi.

Save efi_main() arguments in the startup code on x86_64;
use EFI calling convention for _relocate() on x86_64;
consistently use EFI calling convention for efi_main() everywhere.

Signed-off-by: Ivan Gorinov <ivan.gorinov@intel.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
tags/2020-06-01
Ivan Gorinov 2 years ago
committed by Bin Meng
parent
commit
9f0b0113c9
3 changed files with 17 additions and 13 deletions
  1. +13
    -11
      arch/x86/lib/crt0_x86_64_efi.S
  2. +2
    -1
      lib/efi/efi_app.c
  3. +2
    -1
      lib/efi/efi_stub.c

+ 13
- 11
arch/x86/lib/crt0_x86_64_efi.S View File

@@ -3,7 +3,7 @@
* crt0-efi-x86_64.S - x86_64 EFI startup code.
* Copyright (C) 1999 Hewlett-Packard Co.
* Contributed by David Mosberger <davidm@hpl.hp.com>.
* Copyright (C) 2005 Intel Co.
* Copyright (C) 2005 Intel Corporation
* Contributed by Fenghua Yu <fenghua.yu@intel.com>.
*
* All rights reserved.
@@ -14,26 +14,28 @@
.globl _start
_start:
subq $8, %rsp

pushq %rcx
pushq %rdx

0:
lea image_base(%rip), %rdi
lea _DYNAMIC(%rip), %rsi
mov %rcx, %r8
mov %rdx, %r9

lea image_base(%rip), %rcx
lea _DYNAMIC(%rip), %rdx

popq %rcx
popq %rdx
pushq %rcx
pushq %rdx
call _relocate

popq %rdi
popq %rsi
popq %rdx
popq %rcx

testq %rax, %rax
jnz .exit

call efi_main
.exit:
addq $8, %rsp

.exit:
ret

/*


+ 2
- 1
lib/efi/efi_app.c View File

@@ -96,7 +96,8 @@ static void free_memory(struct efi_priv *priv)
* U-Boot. If it returns, EFI will continue. Another way to get back to EFI
* is via reset_cpu().
*/
efi_status_t efi_main(efi_handle_t image, struct efi_system_table *sys_table)
efi_status_t EFIAPI efi_main(efi_handle_t image,
struct efi_system_table *sys_table)
{
struct efi_priv local_priv, *priv = &local_priv;
efi_status_t ret;


+ 2
- 1
lib/efi/efi_stub.c View File

@@ -268,7 +268,8 @@ static void add_entry_addr(struct efi_priv *priv, enum efi_entry_t type,
* This function is called by our EFI start-up code. It handles running
* U-Boot. If it returns, EFI will continue.
*/
efi_status_t efi_main(efi_handle_t image, struct efi_system_table *sys_table)
efi_status_t EFIAPI efi_main(efi_handle_t image,
struct efi_system_table *sys_table)
{
struct efi_priv local_priv, *priv = &local_priv;
struct efi_boot_services *boot = sys_table->boottime;


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