| /* |
| * 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: |
