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interupt_entry.asm
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extern k_reenter
extern exception_handler
extern kernel_stack
extern itss
extern ready_task
extern isr_tbl
extern sys_call_tbl
extern scheduler
KERNEL_STACK_SIZE equ 200
global divide_error
global single_step_exception
global nmi
global breakpoint_exception
global overflow
global bounds_check
global inval_opcode
global copr_not_available
global double_fault
global copr_seg_overrun
global inval_tss
global segment_not_present
global stack_exception
global general_protection
global page_fault
global copr_error
global hwint00
global hwint01
global hwint02
global hwint03
global hwint04
global hwint05
global hwint06
global hwint07
global hwint08
global hwint09
global hwint10
global hwint11
global hwint12
global hwint13
global hwint14
global hwint15
global sys_call
%macro hwint_master 1
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0x21 ; block same interupt source
or al, (1<<%1)
out 0x21, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push %1
call (isr_tbl + 4 * %1)
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter:
in al, 0x21 ; restore the same interupt
and al, ~(1<<%1)
out 0x21, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
%endmacro
; ---------------------------------
ALIGN 16
hwint00: ; Interrupt routine for irq 0 (the clock).
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0x21 ; block same interupt source
or al, (1<<0)
out 0x21, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter0
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 0
call [isr_tbl + 4 * 0]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter0:
in al, 0x21 ; restore the same interupt
and al, ~(1<<0)
out 0x21, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
;hwint00:
; sub esp, 4
; pushad
; push ds
; push es
; push fs
; push gs
; mov dx, ss ; ss's DPL is 0 which others want to be
; mov ds, dx
; mov es, dx
;
; in al, 0x21 ; block same interupt source
; or al, 1
; out 0x21, al
;
; mov al, 0x20 ; EndOfInterupt
; out 0x20, al
;
; inc dword [k_reenter]
; cmp dword [k_reenter], 0
; jne .re_enter
;
;; move to kernel stack
; mov esp, (kernel_stack + KERNEL_STACK_SIZE)
;
; sti
;; call functions
;; call scheduler
; call [isr_tbl]
;
; cli
;; leave kernel stack to pcb.regs
; mov esp, [ready_task]
; lldt [esp + (18*4)]
; lea eax, [esp + (18*4)]
; mov dword [itss + 4], eax
;
;.re_enter:
;
; in al, 0x21 ; restore the same interupt
; and al, 0xfe
; out 0x21, al
;
; dec dword [k_reenter]
; pop gs
; pop fs
; pop es
; pop ds
; popad
; add esp, 4
; iretd
ALIGN 16
hwint01: ; Interrupt routine for irq 1 (keyboard)
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0x21 ; block same interupt source
or al, (1<<1)
out 0x21, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter1
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 1
call [isr_tbl + 4 * 1]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter1:
in al, 0x21 ; restore the same interupt
and al, ~(1<<1)
out 0x21, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
ALIGN 16
hwint02: ; Interrupt routine for irq 2 (cascade!)
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0x21 ; block same interupt source
or al, (1<<2)
out 0x21, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter2
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 2
call [isr_tbl + 4 * 2]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter2:
in al, 0x21 ; restore the same interupt
and al, ~(1<<2)
out 0x21, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
ALIGN 16
hwint03: ; Interrupt routine for irq 3 (second serial)
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0x21 ; block same interupt source
or al, (1<<3)
out 0x21, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter3
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 3
call [isr_tbl + 4 * 3]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter3:
in al, 0x21 ; restore the same interupt
and al, ~(1<<3)
out 0x21, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
ALIGN 16
hwint04: ; Interrupt routine for irq 4 (first serial)
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0x21 ; block same interupt source
or al, (1<<4)
out 0x21, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter4
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 4
call [isr_tbl + 4 * 4]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter4:
in al, 0x21 ; restore the same interupt
and al, ~(1<<4)
out 0x21, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
ALIGN 16
hwint05: ; Interrupt routine for irq 5 (XT winchester)
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0x21 ; block same interupt source
or al, (1<<5)
out 0x21, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter5
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 5
call [isr_tbl + 4 * 5]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter5:
in al, 0x21 ; restore the same interupt
and al, ~(1<<5)
out 0x21, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
ALIGN 16
hwint06: ; Interrupt routine for irq 6 (floppy)
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0x21 ; block same interupt source
or al, (1<<6)
out 0x21, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter6
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 6
call [isr_tbl + 4 * 6]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter6:
in al, 0x21 ; restore the same interupt
and al, ~(1<<6)
out 0x21, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
ALIGN 16
hwint07: ; Interrupt routine for irq 7 (printer)
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0x21 ; block same interupt source
or al, (1<<7)
out 0x21, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter7
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 7
call [isr_tbl + 4 * 7]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter7:
in al, 0x21 ; restore the same interupt
and al, ~(1<<7)
out 0x21, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
; ---------------------------------
%macro hwint_slave 1
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0xa1 ; block same interupt source
or al, (1<<(%1-8))
out 0xa1, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
nop ; delay
nop
out 0xa0, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter%1
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push %1
call (isr_tbl + 4 * %1)
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter%1:
in al, 0xa1 ; restore the same interupt
and al, ~(1<<(%1-8))
out 0xa1, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
%endmacro
; ---------------------------------
ALIGN 16
hwint08: ; Interrupt routine for irq 8 (realtime clock).
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0xa1 ; block same interupt source
or al, (1<<(8-8))
out 0xa1, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
nop ; delay
nop
out 0xa0, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter8
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 8
call [isr_tbl + 4 * 8]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter8:
in al, 0xa1 ; restore the same interupt
and al, ~(1<<(8-8))
out 0xa1, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
ALIGN 16
hwint09: ; Interrupt routine for irq 9 (irq 2 redirected)
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0xa1 ; block same interupt source
or al, (1<<(9-8))
out 0xa1, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
nop ; delay
nop
out 0xa0, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter9
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 9
call [isr_tbl + 4 * 9]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter9:
in al, 0xa1 ; restore the same interupt
and al, ~(1<<(9-8))
out 0xa1, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
ALIGN 16
hwint10: ; Interrupt routine for irq 10
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0xa1 ; block same interupt source
or al, (1<<(10-8))
out 0xa1, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
nop ; delay
nop
out 0xa0, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter10
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 10
call [isr_tbl + 4 * 10]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter10:
in al, 0xa1 ; restore the same interupt
and al, ~(1<<(10-8))
out 0xa1, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
ALIGN 16
hwint11: ; Interrupt routine for irq 11
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0xa1 ; block same interupt source
or al, (1<<(11-8))
out 0xa1, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
nop ; delay
nop
out 0xa0, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter11
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 11
call [isr_tbl + 4 * 11]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter11:
in al, 0xa1 ; restore the same interupt
and al, ~(1<<(11-8))
out 0xa1, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
ALIGN 16
hwint12: ; Interrupt routine for irq 12
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0xa1 ; block same interupt source
or al, (1<<(12-8))
out 0xa1, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
nop ; delay
nop
out 0xa0, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter12
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 12
call [isr_tbl + 4 * 12]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter12:
in al, 0xa1 ; restore the same interupt
and al, ~(1<<(12-8))
out 0xa1, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
ALIGN 16
hwint13: ; Interrupt routine for irq 13 (FPU exception)
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0xa1 ; block same interupt source
or al, (1<<(13-8))
out 0xa1, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
nop ; delay
nop
out 0xa0, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter13
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 13
call [isr_tbl + 4 * 13]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter13:
in al, 0xa1 ; restore the same interupt
and al, ~(1<<(13-8))
out 0xa1, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
ALIGN 16
hwint14: ; Interrupt routine for irq 14 (AT winchester)
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0xa1 ; block same interupt source
or al, (1<<(14-8))
out 0xa1, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
nop ; delay
nop
out 0xa0, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter14
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 14
call [isr_tbl + 4 * 14]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter14:
in al, 0xa1 ; restore the same interupt
and al, ~(1<<(14-8))
out 0xa1, al
dec dword [k_reenter]
pop gs
pop fs
pop es
pop ds
popad
add esp, 4
iretd
ALIGN 16
hwint15: ; Interrupt routine for irq 15
sub esp, 4
pushad
push ds
push es
push fs
push gs
mov dx, ss ; ss's DPL is 0 which others want to be
mov ds, dx
mov es, dx
in al, 0xa1 ; block same interupt source
or al, (1<<(15-8))
out 0xa1, al
mov al, 0x20 ; EndOfInterupt
out 0x20, al
nop ; delay
nop
out 0xa0, al
inc dword [k_reenter]
cmp dword [k_reenter], 0
jne .re_enter15
mov esp, (kernel_stack + KERNEL_STACK_SIZE)
sti
push 15
call [isr_tbl + 4 * 15]
add esp, 4
cli
mov esp, [ready_task]
lldt [esp + (18*4)]
lea eax, [esp + (18*4)]
mov dword [itss + 4], eax
.re_enter15:
in al, 0xa1 ; restore the same interupt
and al, ~(1<<(15-8))
out 0xa1, al
dec dword [k_reenter]
pop gs