Files
my-os-project2/kernel/intr/pic.c

47 lines
950 B
C

#include <stddef.h>
#include <stdint.h>
#include "io/io.h"
#include "intr/pic.h"
#include "intr/intr.h"
#define PIC1_CMD 0x0020
#define PIC1_DATA 0x0021
#define PIC2_CMD 0x00A0
#define PIC2_DATA 0x00A1
#define PIC_EOI 0x20
#define ICW1_ICW4 0x01
#define ICW1_SINGLE 0x02
#define ICW1_ADI 0x04
#define ICW1_LTIM 0x08
#define ICW1_INIT 0x10
#define ICW4_8086 0x01
#define ICW4_AUTO 0x02
#define ICW4_BUFSLAVE 0x04
#define ICW4_BUFMASTER 0x0C
#define ICW4_SFNM 0x10
void intr_pic_init(void) {
io_out8(PIC1_CMD, ICW1_INIT | ICW1_ICW4);
io_out8(PIC2_CMD, ICW1_INIT | ICW1_ICW4);
io_out8(PIC1_DATA, INTR_IRQBASE);
io_out8(PIC2_DATA, INTR_IRQBASE+8);
io_out8(PIC1_DATA, 2);
io_out8(PIC2_DATA, 2);
io_out8(PIC1_DATA, ICW4_8086);
io_out8(PIC2_DATA, ICW4_8086);
io_out8(PIC1_DATA, 0);
io_out8(PIC2_DATA, 0);
}
void intr_pic_eoi(void) {
io_out8(PIC2_CMD, PIC_EOI);
io_out8(PIC1_CMD, PIC_EOI);
}