ref: 2cab6c0b2f7ccfad3c7990070ab0917cfd978cf1
dir: /os/manga/clock.c/
#include "u.h" #include "../port/lib.h" #include "mem.h" #include "dat.h" #include "fns.h" #include "io.h" #include "ureg.h" enum { Mclk= 25000000 }; typedef struct Clock0link Clock0link; typedef struct Clock0link { void (*clock)(void); Clock0link* link; } Clock0link; static Clock0link *clock0link; static Lock clock0lock; static void (*prof_fcn)(Ureg *, int); Timer* addclock0link(void (*clock)(void), int) { Clock0link *lp; if((lp = malloc(sizeof(Clock0link))) == 0){ print("addclock0link: too many links\n"); return nil; } ilock(&clock0lock); lp->clock = clock; lp->link = clock0link; clock0link = lp; iunlock(&clock0lock); return nil; } static void profintr(Ureg *, void*) { /* TO DO: watchdog, profile on Timer 0 */ } static void clockintr(Ureg*, void*) { Clock0link *lp; static int blip, led; if(++blip >= HZ){ blip = 0; ledset(led ^= 1); } m->ticks++; checkalarms(); if(canlock(&clock0lock)){ for(lp = clock0link; lp; lp = lp->link) if(lp->clock) lp->clock(); unlock(&clock0lock); } /* round robin time slice is done by trap.c and proc.c */ } void installprof(void (*pf)(Ureg *, int)) { USED(pf); } void clockinit(void) { TimerReg *tr; IntrReg *ir; ulong l, u; m->ticks = 0; tr = TIMERREG; tr->enable = 0; tr->pulse1 = 1; /* first tune the delay loop parameter (using a search because the counter doesn't decrement) */ ir = INTRREG; tr->count1 = Mclk/1000 - tr->pulse1; /* millisecond */ u = m->cpuhz/(2*1000); /* over-large estimate for a millisecond */ l = 10000; while(l+1 < u){ m->delayloop = l + (u-l)/2; ir->st = 1<<IRQtm1; /* reset edge */ tr->enable = 1<<1; delay(1); tr->enable = 0; if(ir->st & (1<<IRQtm1)) u = m->delayloop; else l = m->delayloop; } intrenable(IRQ, IRQtm1, clockintr, nil, "timer.1"); tr->count1 = Mclk/HZ - tr->pulse1; tr->enable = 1<<1; /* enable only Timer 1 */ } void clockpoll(void) { } void clockcheck(void) { } uvlong fastticks(uvlong *hz) { if(hz) *hz = HZ; return m->ticks; } void microdelay(int l) { int i; l *= m->delayloop; l /= 1000; if(l <= 0) l = 1; for(i = 0; i < l; i++) ; } void delay(int l) { ulong i, j; j = m->delayloop; while(l-- > 0) for(i=0; i < j; i++) ; } /* * for devkprof.c */ long archkprofmicrosecondspertick(void) { return MS2HZ*1000; } void archkprofenable(int) { /* TO DO */ }