X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=init%2Fcalibrate.c;h=a379c9061199c64368936a88f91353992a4d5f92;hb=a27028349ccbcec9dde9d6dbba9d4017ad9ad5ab;hp=ecb3822d4f70ed177c45318c31aeaf8f58b1273a;hpb=7924e4f6519dd5b349ed146fe9fe35206730be67;p=linux-2.6-omap-h63xx.git

diff --git a/init/calibrate.c b/init/calibrate.c
index ecb3822d4f7..a379c906119 100644
--- a/init/calibrate.c
+++ b/init/calibrate.c
@@ -8,7 +8,9 @@
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/timex.h>
+#include <linux/smp.h>
 
+unsigned long lpj_fine;
 unsigned long preset_lpj;
 static int __init lpj_setup(char *str)
 {
@@ -33,9 +35,9 @@ static unsigned long __cpuinit calibrate_delay_direct(void)
 	unsigned long pre_start, start, post_start;
 	unsigned long pre_end, end, post_end;
 	unsigned long start_jiffies;
-	unsigned long tsc_rate_min, tsc_rate_max;
-	unsigned long good_tsc_sum = 0;
-	unsigned long good_tsc_count = 0;
+	unsigned long timer_rate_min, timer_rate_max;
+	unsigned long good_timer_sum = 0;
+	unsigned long good_timer_count = 0;
 	int i;
 
 	if (read_current_timer(&pre_start) < 0 )
@@ -79,22 +81,24 @@ static unsigned long __cpuinit calibrate_delay_direct(void)
 		}
 		read_current_timer(&post_end);
 
-		tsc_rate_max = (post_end - pre_start) / DELAY_CALIBRATION_TICKS;
-		tsc_rate_min = (pre_end - post_start) / DELAY_CALIBRATION_TICKS;
+		timer_rate_max = (post_end - pre_start) /
+					DELAY_CALIBRATION_TICKS;
+		timer_rate_min = (pre_end - post_start) /
+					DELAY_CALIBRATION_TICKS;
 
 		/*
-	 	 * If the upper limit and lower limit of the tsc_rate is
+		 * If the upper limit and lower limit of the timer_rate is
 		 * >= 12.5% apart, redo calibration.
 		 */
 		if (pre_start != 0 && pre_end != 0 &&
-		    (tsc_rate_max - tsc_rate_min) < (tsc_rate_max >> 3)) {
-			good_tsc_count++;
-			good_tsc_sum += tsc_rate_max;
+		    (timer_rate_max - timer_rate_min) < (timer_rate_max >> 3)) {
+			good_timer_count++;
+			good_timer_sum += timer_rate_max;
 		}
 	}
 
-	if (good_tsc_count)
-		return (good_tsc_sum/good_tsc_count);
+	if (good_timer_count)
+		return (good_timer_sum/good_timer_count);
 
 	printk(KERN_WARNING "calibrate_delay_direct() failed to get a good "
 	       "estimate for loops_per_jiffy.\nProbably due to long platform interrupts. Consider using \"lpj=\" boot option.\n");
@@ -108,6 +112,10 @@ static unsigned long __cpuinit calibrate_delay_direct(void) {return 0;}
  * This is the number of bits of precision for the loops_per_jiffy.  Each
  * bit takes on average 1.5/HZ seconds.  This (like the original) is a little
  * better than 1%
+ * For the boot cpu we can skip the delay calibration and assign it a value
+ * calculated based on the timer frequency.
+ * For the rest of the CPUs we cannot assume that the timer frequency is same as
+ * the cpu frequency, hence do the calibration for those.
  */
 #define LPS_PREC 8
 
@@ -118,20 +126,20 @@ void __cpuinit calibrate_delay(void)
 
 	if (preset_lpj) {
 		loops_per_jiffy = preset_lpj;
-		printk("Calibrating delay loop (skipped)... "
-			"%lu.%02lu BogoMIPS preset\n",
-			loops_per_jiffy/(500000/HZ),
-			(loops_per_jiffy/(5000/HZ)) % 100);
+		printk(KERN_INFO
+			"Calibrating delay loop (skipped) preset value.. ");
+	} else if ((smp_processor_id() == 0) && lpj_fine) {
+		loops_per_jiffy = lpj_fine;
+		printk(KERN_INFO
+			"Calibrating delay loop (skipped), "
+			"value calculated using timer frequency.. ");
 	} else if ((loops_per_jiffy = calibrate_delay_direct()) != 0) {
-		printk("Calibrating delay using timer specific routine.. ");
-		printk("%lu.%02lu BogoMIPS (lpj=%lu)\n",
-			loops_per_jiffy/(500000/HZ),
-			(loops_per_jiffy/(5000/HZ)) % 100,
-			loops_per_jiffy);
+		printk(KERN_INFO
+			"Calibrating delay using timer specific routine.. ");
 	} else {
 		loops_per_jiffy = (1<<12);
 
-		printk(KERN_DEBUG "Calibrating delay loop... ");
+		printk(KERN_INFO "Calibrating delay loop... ");
 		while ((loops_per_jiffy <<= 1) != 0) {
 			/* wait for "start of" clock tick */
 			ticks = jiffies;
@@ -161,12 +169,8 @@ void __cpuinit calibrate_delay(void)
 			if (jiffies != ticks)	/* longer than 1 tick */
 				loops_per_jiffy &= ~loopbit;
 		}
-
-		/* Round the value and print it */
-		printk("%lu.%02lu BogoMIPS (lpj=%lu)\n",
-			loops_per_jiffy/(500000/HZ),
-			(loops_per_jiffy/(5000/HZ)) % 100,
-			loops_per_jiffy);
 	}
-
+	printk(KERN_CONT "%lu.%02lu BogoMIPS (lpj=%lu)\n",
+			loops_per_jiffy/(500000/HZ),
+			(loops_per_jiffy/(5000/HZ)) % 100, loops_per_jiffy);
 }