mirror of https://gitee.com/openkylin/linux.git
42 lines
960 B
ArmAsm
42 lines
960 B
ArmAsm
/*
|
|
* Copyright (C) 2018 Linaro Ltd <ard.biesheuvel@linaro.org>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
|
|
ENTRY(__efi_rt_asm_wrapper)
|
|
stp x29, x30, [sp, #-32]!
|
|
mov x29, sp
|
|
|
|
/*
|
|
* Register x18 is designated as the 'platform' register by the AAPCS,
|
|
* which means firmware running at the same exception level as the OS
|
|
* (such as UEFI) should never touch it.
|
|
*/
|
|
stp x1, x18, [sp, #16]
|
|
|
|
/*
|
|
* We are lucky enough that no EFI runtime services take more than
|
|
* 5 arguments, so all are passed in registers rather than via the
|
|
* stack.
|
|
*/
|
|
mov x8, x0
|
|
mov x0, x2
|
|
mov x1, x3
|
|
mov x2, x4
|
|
mov x3, x5
|
|
mov x4, x6
|
|
blr x8
|
|
|
|
ldp x1, x2, [sp, #16]
|
|
cmp x2, x18
|
|
ldp x29, x30, [sp], #32
|
|
b.ne 0f
|
|
ret
|
|
0: b efi_handle_corrupted_x18 // tail call
|
|
ENDPROC(__efi_rt_asm_wrapper)
|