1*4882a593Smuzhiyun/* SPDX-License-Identifier: GPL-2.0-only */ 2*4882a593Smuzhiyun/* 3*4882a593Smuzhiyun * Copyright (C) 2003,2004 Eric Biederman (ebiederm@xmission.com) 4*4882a593Smuzhiyun * Copyright (C) 2014 Red Hat Inc. 5*4882a593Smuzhiyun 6*4882a593Smuzhiyun * Author(s): Vivek Goyal <vgoyal@redhat.com> 7*4882a593Smuzhiyun * 8*4882a593Smuzhiyun * This code has been taken from kexec-tools. 9*4882a593Smuzhiyun */ 10*4882a593Smuzhiyun 11*4882a593Smuzhiyun#include <linux/linkage.h> 12*4882a593Smuzhiyun 13*4882a593Smuzhiyun .text 14*4882a593Smuzhiyun .balign 16 15*4882a593Smuzhiyun .code64 16*4882a593Smuzhiyun 17*4882a593SmuzhiyunSYM_CODE_START(entry64) 18*4882a593Smuzhiyun /* Setup a gdt that should be preserved */ 19*4882a593Smuzhiyun lgdt gdt(%rip) 20*4882a593Smuzhiyun 21*4882a593Smuzhiyun /* load the data segments */ 22*4882a593Smuzhiyun movl $0x18, %eax /* data segment */ 23*4882a593Smuzhiyun movl %eax, %ds 24*4882a593Smuzhiyun movl %eax, %es 25*4882a593Smuzhiyun movl %eax, %ss 26*4882a593Smuzhiyun movl %eax, %fs 27*4882a593Smuzhiyun movl %eax, %gs 28*4882a593Smuzhiyun 29*4882a593Smuzhiyun /* Setup new stack */ 30*4882a593Smuzhiyun leaq stack_init(%rip), %rsp 31*4882a593Smuzhiyun pushq $0x10 /* CS */ 32*4882a593Smuzhiyun leaq new_cs_exit(%rip), %rax 33*4882a593Smuzhiyun pushq %rax 34*4882a593Smuzhiyun lretq 35*4882a593Smuzhiyunnew_cs_exit: 36*4882a593Smuzhiyun 37*4882a593Smuzhiyun /* Load the registers */ 38*4882a593Smuzhiyun movq rax(%rip), %rax 39*4882a593Smuzhiyun movq rbx(%rip), %rbx 40*4882a593Smuzhiyun movq rcx(%rip), %rcx 41*4882a593Smuzhiyun movq rdx(%rip), %rdx 42*4882a593Smuzhiyun movq rsi(%rip), %rsi 43*4882a593Smuzhiyun movq rdi(%rip), %rdi 44*4882a593Smuzhiyun movq rsp(%rip), %rsp 45*4882a593Smuzhiyun movq rbp(%rip), %rbp 46*4882a593Smuzhiyun movq r8(%rip), %r8 47*4882a593Smuzhiyun movq r9(%rip), %r9 48*4882a593Smuzhiyun movq r10(%rip), %r10 49*4882a593Smuzhiyun movq r11(%rip), %r11 50*4882a593Smuzhiyun movq r12(%rip), %r12 51*4882a593Smuzhiyun movq r13(%rip), %r13 52*4882a593Smuzhiyun movq r14(%rip), %r14 53*4882a593Smuzhiyun movq r15(%rip), %r15 54*4882a593Smuzhiyun 55*4882a593Smuzhiyun /* Jump to the new code... */ 56*4882a593Smuzhiyun jmpq *rip(%rip) 57*4882a593SmuzhiyunSYM_CODE_END(entry64) 58*4882a593Smuzhiyun 59*4882a593Smuzhiyun .section ".rodata" 60*4882a593Smuzhiyun .balign 4 61*4882a593SmuzhiyunSYM_DATA_START(entry64_regs) 62*4882a593Smuzhiyunrax: .quad 0x0 63*4882a593Smuzhiyunrcx: .quad 0x0 64*4882a593Smuzhiyunrdx: .quad 0x0 65*4882a593Smuzhiyunrbx: .quad 0x0 66*4882a593Smuzhiyunrsp: .quad 0x0 67*4882a593Smuzhiyunrbp: .quad 0x0 68*4882a593Smuzhiyunrsi: .quad 0x0 69*4882a593Smuzhiyunrdi: .quad 0x0 70*4882a593Smuzhiyunr8: .quad 0x0 71*4882a593Smuzhiyunr9: .quad 0x0 72*4882a593Smuzhiyunr10: .quad 0x0 73*4882a593Smuzhiyunr11: .quad 0x0 74*4882a593Smuzhiyunr12: .quad 0x0 75*4882a593Smuzhiyunr13: .quad 0x0 76*4882a593Smuzhiyunr14: .quad 0x0 77*4882a593Smuzhiyunr15: .quad 0x0 78*4882a593Smuzhiyunrip: .quad 0x0 79*4882a593SmuzhiyunSYM_DATA_END(entry64_regs) 80*4882a593Smuzhiyun 81*4882a593Smuzhiyun /* GDT */ 82*4882a593Smuzhiyun .section ".rodata" 83*4882a593Smuzhiyun .balign 16 84*4882a593SmuzhiyunSYM_DATA_START_LOCAL(gdt) 85*4882a593Smuzhiyun /* 86*4882a593Smuzhiyun * 0x00 unusable segment 87*4882a593Smuzhiyun * 0x08 unused 88*4882a593Smuzhiyun * so use them as gdt ptr 89*4882a593Smuzhiyun */ 90*4882a593Smuzhiyun .word gdt_end - gdt - 1 91*4882a593Smuzhiyun .quad gdt 92*4882a593Smuzhiyun .word 0, 0, 0 93*4882a593Smuzhiyun 94*4882a593Smuzhiyun /* 0x10 4GB flat code segment */ 95*4882a593Smuzhiyun .word 0xFFFF, 0x0000, 0x9A00, 0x00AF 96*4882a593Smuzhiyun 97*4882a593Smuzhiyun /* 0x18 4GB flat data segment */ 98*4882a593Smuzhiyun .word 0xFFFF, 0x0000, 0x9200, 0x00CF 99*4882a593SmuzhiyunSYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end) 100*4882a593Smuzhiyun 101*4882a593SmuzhiyunSYM_DATA_START_LOCAL(stack) 102*4882a593Smuzhiyun .quad 0, 0 103*4882a593SmuzhiyunSYM_DATA_END_LABEL(stack, SYM_L_LOCAL, stack_init) 104