58 lines
1.0 KiB
ArmAsm
58 lines
1.0 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* purgatory: setup code
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*
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* Copyright (C) 2003,2004 Eric Biederman (ebiederm@xmission.com)
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* Copyright (C) 2014 Red Hat Inc.
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*
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* This code has been taken from kexec-tools.
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*/
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#include <asm/purgatory.h>
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.text
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.globl purgatory_start
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.balign 16
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purgatory_start:
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.code64
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/* Load a gdt so I know what the segment registers are */
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lgdt gdt(%rip)
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/* load the data segments */
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movl $0x18, %eax /* data segment */
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movl %eax, %ds
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movl %eax, %es
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movl %eax, %ss
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movl %eax, %fs
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movl %eax, %gs
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/* Setup a stack */
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leaq lstack_end(%rip), %rsp
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/* Call the C code */
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call purgatory
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jmp entry64
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.section ".rodata"
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.balign 16
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gdt: /* 0x00 unusable segment
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* 0x08 unused
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* so use them as the gdt ptr
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*/
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.word gdt_end - gdt - 1
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.quad gdt
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.word 0, 0, 0
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/* 0x10 4GB flat code segment */
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.word 0xFFFF, 0x0000, 0x9A00, 0x00AF
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/* 0x18 4GB flat data segment */
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.word 0xFFFF, 0x0000, 0x9200, 0x00CF
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gdt_end:
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.bss
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.balign 4096
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lstack:
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.skip 4096
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lstack_end:
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