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Diffstat (limited to 'arch/arm/mach-sa1100/generic.c')
-rw-r--r--arch/arm/mach-sa1100/generic.c15
1 files changed, 11 insertions, 4 deletions
diff --git a/arch/arm/mach-sa1100/generic.c b/arch/arm/mach-sa1100/generic.c
index 4575f316e141..e510295c2580 100644
--- a/arch/arm/mach-sa1100/generic.c
+++ b/arch/arm/mach-sa1100/generic.c
@@ -20,6 +20,7 @@
#include <linux/platform_device.h>
#include <asm/div64.h>
+#include <asm/cnt32_to_63.h>
#include <asm/hardware.h>
#include <asm/system.h>
#include <asm/pgtable.h>
@@ -118,15 +119,21 @@ EXPORT_SYMBOL(cpufreq_get);
/*
* This is the SA11x0 sched_clock implementation. This has
- * a resolution of 271ns, and a maximum value of 1165s.
+ * a resolution of 271ns, and a maximum value of 32025597s (370 days).
+ *
+ * The return value is guaranteed to be monotonic in that range as
+ * long as there is always less than 582 seconds between successive
+ * calls to this function.
+ *
* ( * 1E9 / 3686400 => * 78125 / 288)
*/
unsigned long long sched_clock(void)
{
- unsigned long long v;
+ unsigned long long v = cnt32_to_63(OSCR);
- v = (unsigned long long)OSCR * 78125;
- do_div(v, 288);
+ /* the <<1 gets rid of the cnt_32_to_63 top bit saving on a bic insn */
+ v *= 78125<<1;
+ do_div(v, 288<<1);
return v;
}