swith_to_pm.asm

[ bits 16]
; Switch to protected mode
switch_to_pm :
cli
; We must switch of interrupts until we have
; set - up the protected mode interrupt vector
; otherwise interrupts will run riot.
lgdt [ gdt_descriptor ]

mov eax , cr0
or eax , 0x1
mov cr0 , eax

jmp CODE_SEG : init_pm

[ bits 32]
; Initialise registers and the stack once in PM.
init_pm :
mov ax ,DATA_SEG
mov ds ,ax
mov ss , ax
mov es ,ax
mov fs ,ax
mov gs ,ax

mov ebp , 0x90000
mov esp , ebp

call BEGIN_PM