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[bits 16]
%include "boot/boot_gdt.asm"
switch_to_protected_mode:
; switch off interrupts for now, we don't
; have a valid IDT installed yet
cli
; load GDT (global descriptor table)
lgdt [gdt_descriptor]
; do the actual switch
mov eax, cr0
or eax, 0x1
mov cr0, eax
; unconditional far jump into code segment,
; wipes the instruction prefetch pipeline
jmp CODE_SEGMENT:init_pm
[bits 32]
; initialize registers and stack for protected mode
init_pm:
mov ax, DATA_SEGMENT
mov ds, ax
mov ss, ax
mov es, ax
mov fs, ax
mov gs, ax
; a new stack
mov ebp, 0x90000
mov esp, ebp
call BEGIN_PROTECTED_MODE
[bits 16]
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