Fix Pentium CPU rate diagnosis:

	- Don't print out meaningless iCOMP numbers, those are for droids.
	- Use a shorter wait to determine clock rate to avoid deficiencies
	  in DELAY().
	- Use a fixed-point representation with 8 bits of fraction to store
	  the rate and rationalize the variable name.  It would be
	  possible to use even more fraction if it turns out to be
	  worthwhile (I rather doubt it).

The question of source code arrangement remains unaddressed.

1 files changed, 9 insertions, 4 deletions

diff --git a/sys/i386/include/clock.h b/sys/i386/include/clock.h
index 96476a7..c231f5e 100644
--- a/sys/i386/include/clock.h
+++ b/sys/i386/include/clock.h
@@ -2,6 +2,8 @@
  * Kernel interface to machine-dependent clock driver.
  * Garrett Wollman, September 1994.
  * This file is in the public domain.
+ *
+ *	$Id$
  */
 
 #ifndef _MACHINE_CLOCK_H_
@@ -22,7 +24,7 @@
  */
 #define CPU_CLOCKUPDATE(otime, ntime) \
 	do { \
-	if(pentium_mhz) { \
+	if(i586_ctr_rate) { \
 		disable_intr(); \
 		i586_ctr_bias = i586_last_tick; \
 		*(otime) = *(ntime); \
@@ -39,6 +41,8 @@
 #define CPU_THISTICKLEN(dflt) dflt
 #endif
 
+#define		I586_CTR_RATE_SHIFT	8
+
 #if defined(KERNEL) && !defined(LOCORE)
 #include <sys/cdefs.h>
 #include <machine/frame.h>
@@ -51,7 +55,7 @@
 extern int	adjkerntz;
 extern int	disable_rtc_set;
 #ifdef I586_CPU
-extern int	pentium_mhz;
+extern unsigned	i586_ctr_rate;	/* fixed point */
 extern long long i586_last_tick;
 extern long long i586_ctr_bias;
 #endif
@@ -72,10 +76,11 @@ cpu_thisticklen(u_long dflt)
 	long long old;
 	long rv;
 	
-	if (pentium_mhz) {
+	if (i586_ctr_rate) {
 		old = i586_last_tick;
 		I586_CYCLECTR(i586_last_tick);
-		rv = (i586_last_tick - old) / pentium_mhz;
+		rv = ((i586_last_tick - old) << I586_CTR_RATE_SHIFT)
+			/ i586_ctr_rate;
 	} else {
 		rv = dflt;
 	}