30 lines
520 B
C
30 lines
520 B
C
|
|
#include <socks/printk.h>
|
||
|
|
#include <arch/ports.h>
|
||
|
|
#include <arch/irq.h>
|
||
|
|
|
||
|
|
static int pit_callback(void)
|
||
|
|
{
|
||
|
|
printk("tick");
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static irq_hook_t pit_irq_hook = {
|
||
|
|
.irq_callback = pit_callback
|
||
|
|
};
|
||
|
|
|
||
|
|
void pit_init(unsigned int hz)
|
||
|
|
{
|
||
|
|
unsigned int divisor = 1193180 / hz;
|
||
|
|
|
||
|
|
outportb(0x43, 0x36);
|
||
|
|
uint8_t lo = (uint8_t)(divisor & 0xFF);
|
||
|
|
uint8_t hi = (uint8_t)((divisor >> 8) & 0xFF);
|
||
|
|
|
||
|
|
outportb(0x40, lo);
|
||
|
|
outportb(0x40, hi);
|
||
|
|
|
||
|
|
hook_irq(IRQ0, &pit_irq_hook);
|
||
|
|
|
||
|
|
printk("clock: 8253 PIT initialised at %uHz", hz);
|
||
|
|
}
|