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#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "axp.h"
#include "ureg.h"
void (*kproftimer)(ulong);
typedef struct Clock0link Clock0link;
typedef struct Clock0link {
void (*clock)(void);
Clock0link* link;
} Clock0link;
static Clock0link *clock0link;
static Lock clock0lock;
void
addclock0link(void (*clock)(void))
{
Clock0link *lp;
if((lp = malloc(sizeof(Clock0link))) == 0){
print("addclock0link: too many links\n");
return;
}
ilock(&clock0lock);
lp->clock = clock;
lp->link = clock0link;
clock0link = lp;
iunlock(&clock0lock);
}
void
clockinit(void)
{
}
uvlong
cycletimer(void)
{
ulong pcc;
vlong delta;
pcc = rpcc(nil) & 0xFFFFFFFF;
if(m->cpuhz == 0){
/*
* pcclast is needed to detect wraparound of
* the cycle timer which is only 32-bits.
* m->cpuhz is set from the info passed from
* the firmware.
* This could be in clockinit if can
* guarantee no wraparound between then and now.
*
* All the clock stuff needs work.
*/
m->cpuhz = hwrpb->cfreq;
m->pcclast = pcc;
}
delta = pcc - m->pcclast;
if(delta < 0)
delta += 0x100000000LL;
m->pcclast = pcc;
m->fastclock += delta;
return MACHP(0)->fastclock;
}
vlong
fastticks(uvlong* hz)
{
uvlong ticks;
int x;
x = splhi();
ticks = cycletimer();
splx(x);
if(hz)
*hz = m->cpuhz;
return (vlong)ticks;
}
void
microdelay(int us)
{
uvlong eot;
eot = fastticks(nil) + (m->cpuhz/1000000)*us;
while(fastticks(nil) < eot)
;
}
void
/*milli*/delay(int ms)
{
microdelay(ms*1000);
}
void
clock(Ureg *ur)
{
Clock0link *lp;
static int count;
cycletimer();
/* HZ == 100, timer == 1024Hz. error < 1ms */
count += 100;
if (count < 1024)
return;
count -= 1024;
m->ticks++;
if(m->proc)
m->proc->pc = ur->pc;
accounttime();
if(kproftimer != nil)
kproftimer(ur->pc);
if((active.machs&(1<<m->machno)) == 0)
return;
if(active.exiting && (active.machs & (1<<m->machno))) {
print("someone's exiting\n");
exit(0);
}
checkalarms();
if(m->machno == 0){
lock(&clock0lock);
for(lp = clock0link; lp; lp = lp->link)
lp->clock();
unlock(&clock0lock);
}
if(up == 0 || up->state != Running)
return;
if(anyready())
sched();
/* user profiling clock */
if(ur->status & UMODE) {
(*(ulong*)(USTKTOP-BY2WD)) += TK2MS(1);
segclock(ur->pc);
}
}