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Subject[PATCH 10/14] FRV: Make calibrate_delay() optional
The attached patch makes calibrate_delay() optional. In this architecture, it's
a waste of time since we can predict exactly what it's going to come up with
just by looking at the CPU's hardware clock registers. Thus far, we haven't
seem a board with any clock not dependent on the CPU's clock.

Signed-Off-By: dhowells@redhat.com
---
diffstat frv-calibrate-2610rc1bk10.diff
init/main.c | 70 ---------------------------------------------
lib/Makefile | 3 +
lib/calibrate.c | 86 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 88 insertions(+), 71 deletions(-)

diff -uNr /warthog/kernels/linux-2.6.10-rc1-bk10/init/main.c linux-2.6.10-rc1-bk10-frv/init/main.c
--- /warthog/kernels/linux-2.6.10-rc1-bk10/init/main.c 2004-11-01 11:45:34.000000000 +0000
+++ linux-2.6.10-rc1-bk10-frv/init/main.c 2004-11-01 11:47:05.147633905 +0000
@@ -182,15 +178,6 @@
return 0;
}

-static unsigned long preset_lpj;
-static int __init lpj_setup(char *str)
-{
- preset_lpj = simple_strtoul(str,NULL,0);
- return 1;
-}
-
-__setup("lpj=", lpj_setup);
-
/*
* This should be approx 2 Bo*oMips to start (note initial shift), and will
* still work even if initially too large, it will just take slightly longer
@@ -199,67 +190,6 @@

EXPORT_SYMBOL(loops_per_jiffy);

-/*
- * 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%
- */
-#define LPS_PREC 8
-
-void __devinit calibrate_delay(void)
-{
- unsigned long ticks, loopbit;
- int lps_precision = LPS_PREC;
-
- 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);
- } else {
- loops_per_jiffy = (1<<12);
-
- printk(KERN_DEBUG "Calibrating delay loop... ");
- while ((loops_per_jiffy <<= 1) != 0) {
- /* wait for "start of" clock tick */
- ticks = jiffies;
- while (ticks == jiffies)
- /* nothing */;
- /* Go .. */
- ticks = jiffies;
- __delay(loops_per_jiffy);
- ticks = jiffies - ticks;
- if (ticks)
- break;
- }
-
- /*
- * Do a binary approximation to get loops_per_jiffy set to
- * equal one clock (up to lps_precision bits)
- */
- loops_per_jiffy >>= 1;
- loopbit = loops_per_jiffy;
- while (lps_precision-- && (loopbit >>= 1)) {
- loops_per_jiffy |= loopbit;
- ticks = jiffies;
- while (ticks == jiffies)
- /* nothing */;
- ticks = jiffies;
- __delay(loops_per_jiffy);
- 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);
- }
-
-}
-
static int __init debug_kernel(char *str)
{
if (*str)
diff -uNr /warthog/kernels/linux-2.6.10-rc1-bk10/lib/calibrate.c linux-2.6.10-rc1-bk10-frv/lib/calibrate.c
--- /warthog/kernels/linux-2.6.10-rc1-bk10/lib/calibrate.c 1970-01-01 01:00:00.000000000 +0100
+++ linux-2.6.10-rc1-bk10-frv/lib/calibrate.c 2004-11-01 11:47:05.186630659 +0000
@@ -0,0 +1,86 @@
+/* calibrate.c: default delay calibration
+ *
+ * Excised from init/main.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * GK 2/5/95 - Changed to support mounting root fs via NFS
+ * Added initrd & change_root: Werner Almesberger & Hans Lermen, Feb '96
+ * Moan early if gcc is old, avoiding bogus kernels - Paul Gortmaker, May '96
+ * Simplified starting of init: Michael A. Griffith <grif@acm.org>
+ *
+ */
+
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+
+static unsigned long preset_lpj;
+static int __init lpj_setup(char *str)
+{
+ preset_lpj = simple_strtoul(str,NULL,0);
+ return 1;
+}
+
+__setup("lpj=", lpj_setup);
+
+/*
+ * 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%
+ */
+#define LPS_PREC 8
+
+void __devinit calibrate_delay(void)
+{
+ unsigned long ticks, loopbit;
+ int lps_precision = LPS_PREC;
+
+ 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);
+ } else {
+ loops_per_jiffy = (1<<12);
+
+ printk(KERN_DEBUG "Calibrating delay loop... ");
+ while ((loops_per_jiffy <<= 1) != 0) {
+ /* wait for "start of" clock tick */
+ ticks = jiffies;
+ while (ticks == jiffies)
+ /* nothing */;
+ /* Go .. */
+ ticks = jiffies;
+ __delay(loops_per_jiffy);
+ ticks = jiffies - ticks;
+ if (ticks)
+ break;
+ }
+
+ /*
+ * Do a binary approximation to get loops_per_jiffy set to
+ * equal one clock (up to lps_precision bits)
+ */
+ loops_per_jiffy >>= 1;
+ loopbit = loops_per_jiffy;
+ while (lps_precision-- && (loopbit >>= 1)) {
+ loops_per_jiffy |= loopbit;
+ ticks = jiffies;
+ while (ticks == jiffies)
+ /* nothing */;
+ ticks = jiffies;
+ __delay(loops_per_jiffy);
+ 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);
+ }
+
+}
diff -uNr /warthog/kernels/linux-2.6.10-rc1-bk10/lib/Makefile linux-2.6.10-rc1-bk10-frv/lib/Makefile
--- /warthog/kernels/linux-2.6.10-rc1-bk10/lib/Makefile 2004-11-01 11:45:34.000000000 +0000
+++ linux-2.6.10-rc1-bk10-frv/lib/Makefile 2004-11-01 12:00:25.742993383 +0000
@@ -5,7 +5,8 @@
lib-y := errno.o ctype.o string.o vsprintf.o cmdline.o \
bust_spinlocks.o rbtree.o radix-tree.o dump_stack.o \
kobject.o kref.o idr.o div64.o parser.o int_sqrt.o \
- bitmap.o extable.o kobject_uevent.o find_next_bit.o
+ bitmap.o extable.o kobject_uevent.o find_next_bit.o \
+ calibrate.o

ifeq ($(CONFIG_DEBUG_KOBJECT),y)
CFLAGS_kobject.o += -DDEBUG
-
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