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;-----------------------------------------------------------------------------------

;;;; IN: AL - interrupt number

;;;;     [rmode_ax] .... [rmode_flags] - real mode registers

;;;;

;;;; OUT: [rmode_ax] .... [rmode_flags] - real mode registers



RmodeInt:	pushad

		push es

		push fs

		push gs



		mov [RmodeIntNum],al

		mov ax,ss

		mov [RmodeInt_ss],ax

		mov [RmodeInt_esp],esp



		xor eax,eax

		mov cr3,eax

		jmp DWORD (real_mode_code-_GDT):(RmodeInt0-KERNEL_START)

[BITS 16]

		align 2

RmodeInt0:	cli

		cld

		call PrepareIRQs



		mov ax,real_mode_data-_GDT

		mov ds,ax

		mov es,ax

		mov ss,ax

		mov fs,ax

		mov gs,ax

		lidt [_RM_IDTR]



		mov eax,cr0

		and al,0xFE

		mov cr0,eax

		jmp WORD KERNEL_START_SEG:(RmodeInt1-KERNEL_START)



		align 2

RmodeInt1:	mov ax,0x1000

		mov ss,ax

		mov sp,0



		call RestoreRmodeIRQs



		mov ax,[cs:(rmode_ax-KERNEL_START)]

		mov bx,[cs:(rmode_bx-KERNEL_START)]

		mov cx,[cs:(rmode_cx-KERNEL_START)]

		mov dx,[cs:(rmode_dx-KERNEL_START)]

		mov si,[cs:(rmode_si-KERNEL_START)]

		mov di,[cs:(rmode_di-KERNEL_START)]

		mov bp,[cs:(rmode_bp-KERNEL_START)]

		mov ds,[cs:(rmode_ds-KERNEL_START)]

		mov es,[cs:(rmode_es-KERNEL_START)]



		push WORD [cs:(rmode_flags-KERNEL_START)]

		popf



		sti



		db 0xCD

RmodeIntNum	db 0x00



		cli



		pushf

		pop WORD [cs:(rmode_flags-KERNEL_START)]



		mov [cs:(rmode_es-KERNEL_START)],es

		mov [cs:(rmode_ds-KERNEL_START)],ds

		mov [cs:(rmode_bp-KERNEL_START)],bp

		mov [cs:(rmode_di-KERNEL_START)],di

		mov [cs:(rmode_si-KERNEL_START)],si

		mov [cs:(rmode_dx-KERNEL_START)],dx

		mov [cs:(rmode_cx-KERNEL_START)],cx

		mov [cs:(rmode_bx-KERNEL_START)],bx

		mov [cs:(rmode_ax-KERNEL_START)],ax



		cli

		cld

		call PrepareIRQs

		call A20En



		mov eax,cr0

		or al,1

		mov cr0,eax

		jmp DWORD (kernel_code-_GDT):RmodeInt2

[BITS 32]

		align 4

RmodeInt2:	mov ax,kernel_data-_GDT

		mov ds,ax

		mov es,ax

		mov fs,ax

		mov gs,ax



		mov ax,0x1234

RmodeInt_ss	equ $-2

		mov ss,ax

		mov esp,0x12345678

RmodeInt_esp	equ $-4



		lidt [_IDTR]

		call EnableIRQs



		pop gs

		pop fs

		pop es

		popad

		ret



rmode_ax

rmode_al	db 0

rmode_ah	db 0

rmode_bx

rmode_bl	db 0

rmode_bh	db 0

rmode_cx

rmode_cl	db 0

rmode_ch	db 0

rmode_dx

rmode_dl	db 0

rmode_dh	db 0

rmode_si	dw 0

rmode_di	dw 0

rmode_bp	dw 0

rmode_ds	dw 0

rmode_es	dw 0

rmode_flags	dw 0