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#include "u.h"
#include "lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "ureg.h"
enum {
Timebase = 4, /* system clock cycles per time base cycle */
};
void (*archclocktick)(void); /* set by arch*.c when desired */
static ulong clkreload;
void
delay(int l)
{
ulong i, j;
j = m->delayloop;
while(l-- > 0)
for(i=0; i < j; i++)
;
}
void
microdelay(int l)
{
ulong i;
l *= m->delayloop;
l /= 1000;
if(l <= 0)
l = 1;
for(i = 0; i < l; i++)
;
}
void
clockintr(Ureg*, void*)
{
putdec(clkreload);
m->ticks++;
checkalarms();
if(archclocktick != nil)
archclocktick();
}
void
clockinit(void)
{
long x;
m->delayloop = m->cpuhz/1000; /* initial estimate */
do {
x = gettbl();
delay(10);
x = gettbl() - x;
} while(x < 0);
/*
* fix count
*/
m->delayloop = ((vlong)m->delayloop*(10*m->clockgen/1000))/(x*Timebase);
if(m->delayloop == 0)
m->delayloop = 1;
clkreload = (m->clockgen/Timebase)/HZ-1;
putdec(clkreload);
}
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