time.c

来自「ADS下的bios工程」· C语言 代码 · 共 87 行

#include <bios/s3c2410x.h>
#include <bios/time.h>
#include <bios/timer.h>
#include <bios/stdio.h>

extern int bootFlag ;
extern void Lan_WatchDog(void);
extern void set_IrqAction(int, void (*)());

volatile unsigned int    centisecs;
volatile unsigned int    watch_dog;
struct timer    timers[NR_TIMERS];

void 
clear_timer(int timer)
{
    timers[timer].to = 0;
    timers[timer].status = 0;
}

void 
set_timer(int timer, int cs)
{
    timers[timer].to = cs;
    timers[timer].status = 0;
}

void 
set_timer_fn(int timer, void (*fn)(int))
{
    timers[timer].to_fn = (void (*))fn;
}

static 
void 
led_timeout(int timer)
{
    flash_led(1) ;	/* Turn on/off led 0 only */
    set_timer(timer, 20);
}

void 
time_interrupt(void)
{
    int    i;

    centisecs += 1;

    for (i = 0; i < NR_TIMERS; i ++) {
        if (timers[i].to) {
            timers[i].to -= 1;
            if (timers[i].to == 0) {
                timers[i].status = 1;
                if (timers[i].to_fn) {
                    timers[i].to_fn(i);
                }
            }
        }
    }
}

void 
wait_cs(int cs)
{
    int    target = centisecs + cs;

    while (centisecs < target) 
        ;
}

void 
time_init(void)
{
    centisecs = 0;

    /* setup interrupt controller to IRQ mode */
    INT_ENABLE(INT_TIMER0) ;

    /* setup timer special register, and enable timer */
    s3c24xxx_timer_initialize() ;
    set_IrqAction(INT_TIMER0, time_interrupt) ;

    /* setup logical timer used in bios */
    set_timer(LED_TIMER, 20);
    set_timer_fn(LED_TIMER, led_timeout);
}