1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
|
#include <kernel/arch/amd64/interrupts/irq.h>
#include <kernel/arch/amd64/port_io.h>
#include <stdint.h>
static const int PIC1 = 0x20;
static const int PIC2 = 0xA0;
static void pit_init(void) {
uint16_t divisor = 1193;
port_out8(0x40, divisor & 0xFF);
port_out8(0x40, divisor >> 8);
}
void irq_init(void) {
port_out8(PIC1, 0x11); /* start init sequence */
port_out8(PIC2, 0x11);
port_out8(PIC1+1, IRQ_IBASE); /* interrupt offsets */
port_out8(PIC2+1, IRQ_IBASE + 8);
port_out8(PIC1+1, 0x4);
port_out8(PIC2+1, 0x2);
port_out8(PIC1+1, 0x1);
port_out8(PIC2+1, 0x1);
uint16_t mask = 0xffff;
mask &= ~(1 << 2); // cascade
mask &= ~(1 << IRQ_COM1);
mask &= ~(1 << IRQ_PIT);
mask &= ~(1 << IRQ_PS2KB);
mask &= ~(1 << IRQ_PS2MOUSE);
mask &= ~(1 << IRQ_RTL8139);
port_out8(PIC1+1, mask & 0xff);
port_out8(PIC2+1, (mask >> 8) & 0xff);
pit_init();
}
void irq_eoi(uint8_t line) {
port_out8(PIC1, 0x20);
if (line >= 8)
port_out8(PIC2, 0x20);
}
|
