intr: Ship table with first 16 ISR offsets

This commit is contained in:
Nero 2019-04-09 22:38:20 +00:00
parent befad93b30
commit ac8e07d5ce
3 changed files with 95 additions and 42 deletions

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@ -1,13 +1,3 @@
debug_init:
push bx
push dx
mov bx, 0x002E
mov dx, debug_reg_ir
call ivt_set
pop dx
pop bx
ret
; this kprints registers ; this kprints registers
; expect to be called as interrupt routine ; expect to be called as interrupt routine
debug_reg_ir: debug_reg_ir:

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@ -1,33 +1,102 @@
ivt_backup: ; Data table for interrupts
; cs:word for service routine
intr_table:
dw iret ; 0 Divide by Zero
dw iret ; 1 Single Step
dw iret ; 2 Parity error routine (NMI)
dw debug_reg_ir ; 3 Break
dw iret ; 4 Overflow
dw iret ; 5 Print Screen
dw iret ; 6 Mouse button control
dw iret ; 7 Reserved
dw irq0 ; 8 System Clock interrupt
dw irq1 ; 9 Keyboard interrupt
dw irq2 ; 10 RTC interrupt
dw irq3 ; 11 COMMS
dw irq4 ; 12 COMMS
dw irq5 ; 13 Hard Disk
dw irq6 ; 14 Floppy Disk interrupt routine
dw irq7 ; 15 Printer interrupt
; LSB is IRQ0, MSB is IRQ16
; A IRQ will set their bit to 1, so userspace may poll it via wait_irq
intr_flip:
dw 0
intr_init:
push ds push ds
push es push es
; backup intr 0x0n to 0x4n
xor ax, ax xor ax, ax
mov ds, ax mov ds, ax ; read from IVT
mov es, ax mov es, ax ; write to IVT
mov si, ax mov si, ax ; read from start of IVT table
mov di, 0x0100 ; int 0x40 address mov di, 0x0100 ; write to offset of int 0x40 address
mov cx, 0x0040 ; 0x20 interrupts * 2 words mov cx, 0x0020 ; 0x10 interrupts, segment:offset each
repe movsw repe movsw
; now setup our own handlers
mov ax, cs
mov ds, ax ; read from local segment
mov si, intr_table ; read from intr_table
mov di, 0x0000 ; write to start of IVT table
mov cx, 0x0010 ; 0x10 interupts, one offset each
.loop:
movsw ; read offset, write offset
mov ax,cs
stosw ; write segment
loop .loop
pop es pop es
pop ds pop ds
ret ret
; set item in interrupt vector table irq0:
; in: bx interrupt number int 0x48
; cs:dx new handler address or byte [intr_flip], 0x01
ivt_set: jmp irqret
irq1:
int 0x49
or byte [intr_flip], 0x02
push ax push ax
push es mov ax, [intr_flip]
call kprint8
xor ax,ax mov word [intr_flip], 0x0000
mov es,ax
sal bx,1
sal bx,1
mov [es:bx], dx
mov [es:bx+2], cs
pop es
pop ax pop ax
ret jmp irqret
irq2:
int 0x4A
or byte [intr_flip], 0x04
jmp irqret
irq3:
int 0x4B
or byte [intr_flip], 0x08
jmp irqret
irq4:
int 0x4C
or byte [intr_flip], 0x10
jmp irqret
irq5:
int 0x4D
or byte [intr_flip], 0x20
jmp irqret
irq6:
int 0x4E
or byte [intr_flip], 0x40
jmp irqret
irq7:
int 0x4F
or byte [intr_flip], 0x80
jmp irqret
hwiret:
mov al,20h
out 20h,al
irqret:
iret:
iret

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@ -10,21 +10,15 @@ _startup:
; so we need a nop sled ; so we need a nop sled
times (0x10 - ($-$$)) nop times (0x10 - ($-$$)) nop
main: main:
call hma_relocate call intr_init
call ivt_backup
call debug_init
int 0x2E int 3
mov ax,0x1234
int 0x2E
call kprint16
sti
.halt: .halt:
hlt hlt
jmp .halt jmp .halt
%include "hma.asm"
%include "heap.asm" %include "heap.asm"
%include "intr.asm" %include "intr.asm"
%include "debug.asm" %include "debug.asm"