ref: c0d21d35b103e980e658fff1ef07107e72a03364
parent: 385f52183ce6ce08bf409f389d2386956d6d5fa8
author: cinap_lenrek <cinap_lenrek@felloff.net>
date: Wed Nov 7 12:02:09 EST 2018
bcm: cleanup timer code - calculate hardcoded constants for more clarity - avoid unneccesary modification of cntpns ctl register - revert enabling IRQcntpns for cpu0 - remove unused Localintpending register offset constant
--- a/sys/src/9/bcm/clock.c
+++ b/sys/src/9/bcm/clock.c
@@ -28,7 +28,6 @@
Localctl = 0x00,
Prescaler = 0x08,
- Localintpending = 0x60,
SystimerFreq = 1*Mhz,
MaxPeriod = SystimerFreq / HZ,
@@ -98,7 +97,6 @@
{
if(m->machno == 0)
panic("cpu0: Unexpected local generic timer interrupt");
- cpwrsc(0, CpTIMER, CpTIMERphys, CpTIMERphysctl, Imask);
timerintr(ureg, 0);
}
@@ -116,16 +114,22 @@
{
Systimers *tn;
Armtimer *tm;
- u32int t0, t1, tstart, tend;
+ ulong t0, t1, tstart, tend;
if(((cprdsc(0, CpID, CpIDfeat, 1) >> 16) & 0xF) != 0) {
/* generic timer supported */
+ cpwrsc(0, CpTIMER, CpTIMERphys, CpTIMERphysval, ~0);
if(m->machno == 0){
- *(ulong*)(ARMLOCAL + Localctl) = 0; /* input clock is 19.2Mhz crystal */
- *(ulong*)(ARMLOCAL + Prescaler) = 0x06aaaaab; /* divide by (2^31/Prescaler) for 1Mhz */
+ cpwrsc(0, CpTIMER, CpTIMERphys, CpTIMERphysctl, Imask);
+
+ /* input clock is 19.2Mhz crystal */
+ *(ulong*)(ARMLOCAL + Localctl) = 0;
+ /* divide by (2^31/Prescaler) */
+ *(ulong*)(ARMLOCAL + Prescaler) = (((uvlong)SystimerFreq<<31)/19200000)&~1UL;
+ } else {
+ cpwrsc(0, CpTIMER, CpTIMERphys, CpTIMERphysctl, Enable);
+ intrenable(IRQcntpns, localclockintr, nil, 0, "clock");
}
- cpwrsc(0, CpTIMER, CpTIMERphys, CpTIMERphysctl, Imask);
- intrenable(IRQcntpns, localclockintr, nil, 0, "clock");
}
tn = (Systimers*)SYSTIMERS;
@@ -133,7 +137,7 @@
do{
t0 = lcycles();
}while(tn->clo == tstart);
- tend = tstart + 10000;
+ tend = tstart + (SystimerFreq/100);
do{
t1 = lcycles();
}while(tn->clo != tend);
@@ -141,12 +145,14 @@
m->cpuhz = 100 * t1;
m->cpumhz = (m->cpuhz + Mhz/2 - 1) / Mhz;
m->cyclefreq = m->cpuhz;
+
if(m->machno == 0){
tn->c3 = tn->clo - 1;
+ intrenable(IRQtimer3, clockintr, nil, 0, "clock");
+
tm = (Armtimer*)ARMTIMER;
tm->load = 0;
tm->ctl = TmrPrescale1|CntEnable|CntWidth32;
- intrenable(IRQtimer3, clockintr, nil, 0, "clock");
}
}
@@ -163,10 +169,9 @@
period = MinPeriod;
else if(period > MaxPeriod)
period = MaxPeriod;
- if(m->machno > 0){
+ if(m->machno)
cpwrsc(0, CpTIMER, CpTIMERphys, CpTIMERphysval, period);
- cpwrsc(0, CpTIMER, CpTIMERphys, CpTIMERphysctl, Enable);
- }else{
+ else{
tn = (Systimers*)SYSTIMERS;
tn->c3 = tn->clo + period;
}