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#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#define clockmgr ((u32int*)(CLOCKMGR_BASE))
uvlong timerhz;
enum {
TIMERDIV = 1,
LTIMERDIV = 1,
GTIMERVALL = 0x200/4,
GTIMERVALH,
GTIMERCTL,
LTIMERVAL = 0x604/4,
LTIMERCTL,
LTIMERISR,
};
void
microdelay(int n)
{
ulong now;
now = µs();
while(µs() - now < n);
}
void
delay(int n)
{
while(--n >= 0)
microdelay(1000);
}
uvlong
fastticks(uvlong *hz)
{
ulong lo, hi;
if(hz != nil)
*hz = timerhz;
do{
hi = mpcore[GTIMERVALH];
lo = mpcore[GTIMERVALL];
}while(hi != mpcore[GTIMERVALH]);
return lo | (uvlong)hi << 32;
}
ulong
µs(void)
{
return fastticks2us(fastticks(nil));
}
void
timerset(Tval v)
{
vlong w;
w = v - fastticks(nil);
if(w < 1)
w = 1;
if(w > 0xffffffffLL)
w = 0xffffffff;
mpcore[LTIMERCTL] &= ~1;
mpcore[LTIMERVAL] = w;
mpcore[LTIMERCTL] |= 1;
}
void
timerirq(Ureg *u, void *)
{
if((mpcore[LTIMERISR] & 1) != 0){
mpcore[LTIMERISR] |= 1;
timerintr(u, 0);
}
}
void
timerinit(void)
{
u32int vco;
u64int hz;
int denum, numer, mpuclk;
vco = clockmgr[0x40 / 4];
denum = vco >> 16 & 0x3f;
numer = vco >> 3 & 0x1fff;
mpuclk = clockmgr[0x48 / 4] & 0x1ff;
hz = HPS_CLK * 1000000 * (numer + 1) / ((denum + 1) * 2 * (mpuclk + 1));
m->cpumhz = (hz + 500000) / 1000000;
m->cpuhz = hz;
timerhz = m->cpuhz / 4;
mpcore[GTIMERCTL] = TIMERDIV - 1 << 8 | 3;
mpcore[LTIMERCTL] = LTIMERDIV - 1 << 8 | 4;
intrenable(TIMERIRQ, timerirq, nil, EDGE, "clock");
}
/*
* synchronize all cpu's cycle counter registers
*/
void
synccycles(void)
{
}
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