timer.c

Commit: d8432d7b Author: jokerz Raw Copy

/* ============================================================================

 * Pactor64 — PIT Timer Driver (x86-64)

 * IRQ0 (INT 0x20), 100 Hz default, monotonic tick counter

 * ============================================================================ */

#include "../include/pactor64.h"

/* === Tick Counters === */

static volatile uint64_t timer_ticks    = 0;

static volatile uint64_t timer_seconds  = 0;

/* Forward declaration — defined in idt.c */

extern void irq_install(int irq, void (*handler)(registers_t *regs));

/* === Timer ISR (IRQ0) === */

static void timer_isr(registers_t *regs) {

    (void)regs;

    timer_ticks++;

    if (timer_ticks % 100 == 0) {

        timer_seconds++;

    }

}

/* === Initialize PIT at given frequency === */

void timer_init(uint32_t hz) {

    uint32_t divisor = 1193182 / hz;

    /* Channel 0, lobyte/hibyte, rate generator (mode 2) */

    outb(0x43, 0x34);

    outb(0x40, divisor & 0xFF);

    outb(0x40, (divisor >> 8) & 0xFF);

    /* Register our ISR for IRQ0 and unmask it */

    irq_install(0x20, timer_isr);

    pic_unmask_irq(0);

}

uint64_t timer_get_ticks(void) {

    return timer_ticks;

}

uint64_t timer_get_seconds(void) {

    return timer_seconds;

}

1	/* ============================================================================
2	* Pactor64 — PIT Timer Driver (x86-64)
3	* IRQ0 (INT 0x20), 100 Hz default, monotonic tick counter
4	* ============================================================================ */
5	#include "../include/pactor64.h"
6
7	/* === Tick Counters === */
8	static volatile uint64_t timer_ticks = 0;
9	static volatile uint64_t timer_seconds = 0;
10
11	/* Forward declaration — defined in idt.c */
12	extern void irq_install(int irq, void (handler)(registers_t regs));
13
14	/* === Timer ISR (IRQ0) === */
15	static void timer_isr(registers_t *regs) {
16	(void)regs;
17	timer_ticks++;
18	if (timer_ticks % 100 == 0) {
19	timer_seconds++;
20	}
21	}
22
23	/* === Initialize PIT at given frequency === */
24	void timer_init(uint32_t hz) {
25	uint32_t divisor = 1193182 / hz;
26
27	/* Channel 0, lobyte/hibyte, rate generator (mode 2) */
28	outb(0x43, 0x34);
29	outb(0x40, divisor & 0xFF);
30	outb(0x40, (divisor >> 8) & 0xFF);
31
32	/* Register our ISR for IRQ0 and unmask it */
33	irq_install(0x20, timer_isr);
34	pic_unmask_irq(0);
35	}
36
37	uint64_t timer_get_ticks(void) {
38	return timer_ticks;
39	}
40
41	uint64_t timer_get_seconds(void) {
42	return timer_seconds;
43	}
44