| /* | |
| * 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. | |
| */ | |
| .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: |