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| /*
| * purgatory: setup code
| *
| * Copyright (C) 2003,2004 Eric Biederman (ebiederm@xmission.com)
| * Copyright (C) 2014 Red Hat Inc.
| *
| * 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.
| */
| #include <asm/purgatory.h>
|
| .text
| .globl purgatory_start
| .balign 16
| purgatory_start:
| .code64
|
| /* Load a gdt so I know what the segment registers are */
| 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 a stack */
| leaq lstack_end(%rip), %rsp
|
| /* Call the C code */
| call purgatory
| jmp entry64
|
| .section ".rodata"
| .balign 16
| gdt: /* 0x00 unusable segment
| * 0x08 unused
| * so use them as the 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:
|
| .bss
| .balign 4096
| lstack:
| .skip 4096
| lstack_end:
|
|
