48 lines
585 B
ArmAsm
48 lines
585 B
ArmAsm
.file "srt0.S"
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#define BOOTSTACK 0xfffc
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#define CR0_PE 0x00000001 /* Protected mode Enable */
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.globl end
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.globl edata
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.globl Gdtr
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.globl boot
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.text
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.code16
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.align 16
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.globl _start
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_start:
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popl %eax
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cmpl $BOOTMAGIC, %eax
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je 1f
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1:
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popl %edx
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cli
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pushl %cs
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popl %ds
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addr32 data32 lgdt (Gdtr - LINKADDR)
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movl %cr0, %eax
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orl $CR0_PE, %eax
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data32 movl %eax, %cr0
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data32 ljmp $8, $1f
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1:
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.code32
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movl $0x10, %eax
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mov %ax, %ds
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mov %ax, %ss
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mov %ax, %es
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mov %ax, %fs
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mov %ax, %gs
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movl $BOOTSTACK, %esp
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pushl %edx
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// fill 0 .bss
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xorl %eax, %eax
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call boot;
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