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, 8 insertions, 8 deletions

diff --git a/sys/isa/atrtc.c b/sys/isa/atrtc.c
index 7259a33..82e0b18 100644
--- a/sys/isa/atrtc.c
+++ b/sys/isa/atrtc.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)clock.c	7.2 (Berkeley) 5/12/91
- *	$Id: clock.c,v 1.37 1995/10/12 20:39:49 wollman Exp $
+ *	$Id: clock.c,v 1.38 1995/10/28 15:38:49 phk Exp $
  */
 
 /*
@@ -94,7 +94,7 @@ int	adjkerntz = 0;		/* offset from CMOS clock */
 int	disable_rtc_set	= 0;	/* disable resettodr() if != 0 */
 u_int	idelayed;
 #ifdef I586_CPU
-int	pentium_mhz;
+unsigned	i586_ctr_rate;
 long long	i586_ctr_bias;
 long long	i586_last_tick;
 #endif
@@ -295,13 +295,13 @@ calibrate_cyclecounter(void)
 	 */
 	unsigned long long count;
 
+#define howlong ((unsigned)4*tick)
 	__asm __volatile(".byte 0x0f, 0x30" : : "A"(0LL), "c" (0x10));
-	DELAY(1000000);
+	DELAY(howlong);
 	__asm __volatile(".byte 0xf,0x31" : "=A" (count));
-	/*
-	 * XX lose if the clock rate is not nearly a multiple of 1000000.
-	 */
-	pentium_mhz = (count + 500000) / 1000000;
+
+	i586_ctr_rate = (count << I586_CTR_RATE_SHIFT) / howlong;
+#undef howlong
 }
 #endif
 
@@ -573,7 +573,7 @@ cpu_initclocks()
 	/*
 	 * Finish setting up anti-jitter measures.
 	 */
-	if (pentium_mhz) {
+	if (i586_ctr_rate) {
 		I586_CYCLECTR(i586_last_tick);
 		i586_ctr_bias = i586_last_tick;
 	}