pc/pc64: move common code to pc/devarch.c

1 files changed, 59 insertions, 0 deletions

diff --git a/sys/src/9/pc/devarch.c b/sys/src/9/pc/devarch.c
index 71824f631..4c1ecb691 100644
--- a/sys/src/9/pc/devarch.c
+++ b/sys/src/9/pc/devarch.c
@@ -1133,3 +1133,62 @@ timerset(Tval x)
 	if(doi8253set)
 		(*arch->timerset)(x);
 }
+
+/*
+ *  put the processor in the halt state if we've no processes to run.
+ *  an interrupt will get us going again.
+ *
+ *  halting in an smp system can result in a startup latency for
+ *  processes that become ready.
+ *  if idle_spin is zero, we care more about saving energy
+ *  than reducing this latency.
+ *
+ *  the performance loss with idle_spin == 0 seems to be slight
+ *  and it reduces lock contention (thus system time and real time)
+ *  on many-core systems with large values of NPROC.
+ */
+void
+idlehands(void)
+{
+	extern int nrdy, idle_spin;
+
+	if(conf.nmach == 1)
+		halt();
+	else if(m->cpuidcx & Monitor)
+		mwait(&nrdy);
+	else if(idle_spin == 0)
+		halt();
+}
+
+int
+isaconfig(char *class, int ctlrno, ISAConf *isa)
+{
+	char cc[32], *p;
+	int i;
+
+	snprint(cc, sizeof cc, "%s%d", class, ctlrno);
+	p = getconf(cc);
+	if(p == nil)
+		return 0;
+
+	isa->type = "";
+	isa->nopt = tokenize(p, isa->opt, NISAOPT);
+	for(i = 0; i < isa->nopt; i++){
+		p = isa->opt[i];
+		if(cistrncmp(p, "type=", 5) == 0)
+			isa->type = p + 5;
+		else if(cistrncmp(p, "port=", 5) == 0)
+			isa->port = strtoul(p+5, &p, 0);
+		else if(cistrncmp(p, "irq=", 4) == 0)
+			isa->irq = strtoul(p+4, &p, 0);
+		else if(cistrncmp(p, "dma=", 4) == 0)
+			isa->dma = strtoul(p+4, &p, 0);
+		else if(cistrncmp(p, "mem=", 4) == 0)
+			isa->mem = strtoul(p+4, &p, 0);
+		else if(cistrncmp(p, "size=", 5) == 0)
+			isa->size = strtoul(p+5, &p, 0);
+		else if(cistrncmp(p, "freq=", 5) == 0)
+			isa->freq = strtoul(p+5, &p, 0);
+	}
+	return 1;
+}