100 lines
1.8 KiB
ArmAsm
100 lines
1.8 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* Copyright (C) 2003,2004 Eric Biederman (ebiederm@xmission.com)
|
|
* Copyright (C) 2014 Red Hat Inc.
|
|
|
|
* Author(s): Vivek Goyal <vgoyal@redhat.com>
|
|
*
|
|
* This code has been taken from kexec-tools.
|
|
*/
|
|
|
|
.text
|
|
.balign 16
|
|
.code64
|
|
.globl entry64, entry64_regs
|
|
|
|
|
|
entry64:
|
|
/* Setup a gdt that should be preserved */
|
|
lgdt gdt(%rip)
|
|
|
|
/* load the data segments */
|
|
movl $0x18, %eax /* data segment */
|
|
movl %eax, %ds
|
|
movl %eax, %es
|
|
movl %eax, %ss
|
|
movl %eax, %fs
|
|
movl %eax, %gs
|
|
|
|
/* Setup new stack */
|
|
leaq stack_init(%rip), %rsp
|
|
pushq $0x10 /* CS */
|
|
leaq new_cs_exit(%rip), %rax
|
|
pushq %rax
|
|
lretq
|
|
new_cs_exit:
|
|
|
|
/* Load the registers */
|
|
movq rax(%rip), %rax
|
|
movq rbx(%rip), %rbx
|
|
movq rcx(%rip), %rcx
|
|
movq rdx(%rip), %rdx
|
|
movq rsi(%rip), %rsi
|
|
movq rdi(%rip), %rdi
|
|
movq rsp(%rip), %rsp
|
|
movq rbp(%rip), %rbp
|
|
movq r8(%rip), %r8
|
|
movq r9(%rip), %r9
|
|
movq r10(%rip), %r10
|
|
movq r11(%rip), %r11
|
|
movq r12(%rip), %r12
|
|
movq r13(%rip), %r13
|
|
movq r14(%rip), %r14
|
|
movq r15(%rip), %r15
|
|
|
|
/* Jump to the new code... */
|
|
jmpq *rip(%rip)
|
|
|
|
.section ".rodata"
|
|
.balign 4
|
|
entry64_regs:
|
|
rax: .quad 0x0
|
|
rcx: .quad 0x0
|
|
rdx: .quad 0x0
|
|
rbx: .quad 0x0
|
|
rsp: .quad 0x0
|
|
rbp: .quad 0x0
|
|
rsi: .quad 0x0
|
|
rdi: .quad 0x0
|
|
r8: .quad 0x0
|
|
r9: .quad 0x0
|
|
r10: .quad 0x0
|
|
r11: .quad 0x0
|
|
r12: .quad 0x0
|
|
r13: .quad 0x0
|
|
r14: .quad 0x0
|
|
r15: .quad 0x0
|
|
rip: .quad 0x0
|
|
.size entry64_regs, . - entry64_regs
|
|
|
|
/* GDT */
|
|
.section ".rodata"
|
|
.balign 16
|
|
gdt:
|
|
/* 0x00 unusable segment
|
|
* 0x08 unused
|
|
* so use them as gdt ptr
|
|
*/
|
|
.word gdt_end - gdt - 1
|
|
.quad gdt
|
|
.word 0, 0, 0
|
|
|
|
/* 0x10 4GB flat code segment */
|
|
.word 0xFFFF, 0x0000, 0x9A00, 0x00AF
|
|
|
|
/* 0x18 4GB flat data segment */
|
|
.word 0xFFFF, 0x0000, 0x9200, 0x00CF
|
|
gdt_end:
|
|
stack: .quad 0, 0
|
|
stack_init:
|