plan9fox/sys/src/9/zynq/timer.c

123 lines
1.7 KiB
C

#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
enum {
TIMERDIV = 1,
LTIMERDIV = 1,
ARM_PLL_CTRL = 0x100/4,
ARM_CLK_CTRL = 0x120/4,
GTIMERVALL = 0x200/4,
GTIMERVALH,
GTIMERCTL,
LTIMERVAL = 0x604/4,
LTIMERCTL,
LTIMERISR,
};
uvlong timerhz;
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)
{
m->cpumhz = PS_CLK * (slcr[ARM_PLL_CTRL] >> 12 & 0x7f) / (slcr[ARM_CLK_CTRL] >> 8 & 0x3f);
m->cpuhz = m->cpumhz * 1000000;
timerhz = m->cpuhz / 2;
mpcore[GTIMERCTL] = TIMERDIV - 1 << 8 | 3;
mpcore[LTIMERCTL] = LTIMERDIV - 1 << 8 | 4;
intrenable(TIMERIRQ, timerirq, nil, EDGE, "clock");
/* enable and reset cycle counter register */
m->cyclefreq = m->cpuhz;
setpmcnten((1<<31));
coherence();
setpmcr(7);
}
/*
* synchronize all cpu's cycle counter registers
*/
void
synccycles(void)
{
static Ref r1, r2;
int s;
s = splhi();
r2.ref = 0;
incref(&r1);
while(r1.ref != conf.nmach)
;
setpmcr(7);
m->cycleshi = MACHP(0)->cycleshi;
incref(&r2);
while(r2.ref != conf.nmach)
;
r1.ref = 0;
splx(s);
}