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# Protected mode tables are statically initialised during compile
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# Protected mode tables are statically initialised during compile
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# time. So we can just load the respective table registers and
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# time. So we can just load the respective table registers and
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# switch to protected mode.
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# switch to protected mode.
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#
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#
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kernel_image_start:
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kernel_image_start:
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	cli
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	xorw %ax,%ax
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	movw %ax,%ds
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	movw %ax,%ss            # initialize stack segment register
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	movl $0x7c00,%esp	# initialize stack pointer
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	call memmap_arch_init
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	mov $0x80000000, %eax
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	cpuid
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	cmp $0x80000000, %eax 	# any function > 80000000h?
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	jbe no_long_mode
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	mov $0x80000001, %eax	# Extended function code 80000001
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	cpuid
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	bt $29, %edx 		# Test if long mode is supported.
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	jnc no_long_mode
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# Fill out GDTR.base, IDTR.base
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meeting_point:
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	leal gdtr, %eax
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	movl gdt_addr, %ebx
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.code32
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	movl %ebx, 2(%eax)
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	movl idt_addr, %ebx
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	leal idtr, %eax
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	movl %ebx, 2(%eax)
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# Load gdtr, idtr
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	lgdt gdtr
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	lidt idtr
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	mov $1, %eax    # Enable protected mode (CR0.PE = 1)
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.section K_DATA_START
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	mov %eax, %cr0
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	jmpl $8, $now_in_prot
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now_in_prot:
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no_long_mode:
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1:
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	jmp 1b
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.section K_DATA_START
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.align 4096
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.align 4096
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page_directory:
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page_directory:
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	.space 4096, 0
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	.space 4096, 0
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gdt_addr:
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	.quad gdt + 0x80000000
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idt_addr:
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	.quad idt + 0x80000000