1 files changed, 145 insertions, 0 deletions
diff --git a/os/mpc/clock.c b/os/mpc/clock.c
new file mode 100644
index 00000000..f8ed362f
--- /dev/null
+++ b/os/mpc/clock.c
@@ -0,0 +1,145 @@
+#include	"u.h"
+#include	"../port/lib.h"
+#include	"mem.h"
+#include	"dat.h"
+#include	"fns.h"
+#include	"io.h"
+#include	"ureg.h"
+
+#include	<isa.h>
+#include	<interp.h>
+
+typedef struct Clock0link Clock0link;
+typedef struct Clock0link {
+	void		(*clock)(void);
+	Clock0link*	link;
+} Clock0link;
+
+static Clock0link *clock0link;
+static Lock clock0lock;
+ulong	clkrelinq;
+void	(*kproftick)(ulong);	/* set by devkprof.c when active */
+void	(*archclocktick)(void);	/* set by arch*.c when desired */
+
+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;
+}
+
+void
+delay(int l)
+{
+	ulong i, j;
+
+	j = m->delayloop;
+	while(l-- > 0)
+		for(i=0; i < j; i++)
+			;
+}
+
+void
+microdelay(int l)
+{
+	ulong i;
+
+	l *= m->delayloop;
+	l /= 1000;
+	if(l <= 0)
+		l = 1;
+	for(i = 0; i < l; i++)
+		;
+}
+
+enum {
+	Timebase = 4,	/* system clock cycles per time base cycle */
+};
+
+static	ulong	clkreload;
+
+void
+clockinit(void)
+{
+	long x;
+
+	m->delayloop = m->cpuhz/1000;	/* initial estimate */
+	do {
+		x = gettbl();
+		delay(10);
+		x = gettbl() - x;
+	} while(x < 0);
+
+	/*
+	 *  fix count
+	 */
+	m->delayloop = ((vlong)m->delayloop*(10*m->clockgen/1000))/(x*Timebase);
+	if(m->delayloop == 0)
+		m->delayloop = 1;
+
+	clkreload = (m->clockgen/Timebase)/HZ-1;
+	putdec(clkreload);
+}
+
+void
+clockintr(Ureg *ur)
+{
+	Clock0link *lp;
+	long v;
+
+	v = -getdec();
+	if(v > clkreload/2){
+		if(v > clkreload)
+			m->ticks += v/clkreload;
+		v = 0;
+	}
+	putdec(clkreload-v);
+
+	/* watchdog */
+	if(m->iomem->sypcr & (1<<2)){
+		m->iomem->swsr = 0x556c;
+		m->iomem->swsr = 0xaa39;
+	}
+
+	m->ticks++;
+	if(archclocktick != nil)
+		archclocktick();
+
+	if(up)
+		up->pc = ur->pc;
+
+	checkalarms();
+	if(m->machno == 0) {
+		if(kproftick != nil)
+			(*kproftick)(ur->pc);
+		if(canlock(&clock0lock)){
+			for(lp = clock0link; lp; lp = lp->link)
+				lp->clock();
+			unlock(&clock0lock);
+		}
+	}
+
+	if(up && up->state == Running){
+		if(cflag && up->type == Interp && tready(nil))
+			ur->cr |= 1;	/* set flag in condition register for ../../libinterp/comp-power.c:/^schedcheck */
+	}
+	/* other preemption checks are done by trap.c */
+}
+
+uvlong
+fastticks(uvlong *hz)
+{
+	if(hz)
+		*hz = HZ;
+	return m->ticks;
+}