/* | |
* 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. | |
* | |
* This source code is licensed under the GNU General Public License, | |
* Version 2. See the file COPYING for more details. | |
*/ | |
.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: |