41 lines
652 B
ArmAsm
41 lines
652 B
ArmAsm
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#include "memory.h"
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#include "gdt.h"
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.text
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.code16
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.global gotopmode
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gotopmode:
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jmp 1f
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1:
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xorl %eax,%eax
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movl %ds,%ax
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shl $0x4,%eax
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add %eax,(2f)
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movl %cr0, %eax
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orb $0x01, %al
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movl %eax, %cr0
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.byte 0x66, 0xea
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2: .long pmode
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.word SEL_KERNEL_CODE
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.code32
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.section ".text32","ax"
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.global pmode
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pmode:
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movw $SEL_KERNEL_DATA, %ax
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movw %ax, %ds
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movw %ax, %es
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movw %ax, %fs
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movw %ax, %gs
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movl $KERNEL_CODE_ADDR, %ebx
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movw $SEL_KERNEL_STACK, %ax
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movw %ax, %ss
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movl $KERNEL_STACK_ADDR, %esp
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xor %eax,%eax
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xor %ecx,%ecx
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xor %edx,%edx
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xor %esi,%esi
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xor %edi,%edi
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xor %ebp,%ebp
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jmp *%ebx
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