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Diffstat (limited to 'arch/arm/mach-sa1100/time.c')
-rw-r--r--arch/arm/mach-sa1100/time.c36
1 files changed, 31 insertions, 5 deletions
diff --git a/arch/arm/mach-sa1100/time.c b/arch/arm/mach-sa1100/time.c
index 74b6e0e570b..ae4f3d80416 100644
--- a/arch/arm/mach-sa1100/time.c
+++ b/arch/arm/mach-sa1100/time.c
@@ -12,12 +12,39 @@
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
+#include <linux/sched.h> /* just for sched_clock() - funny that */
#include <linux/timex.h>
#include <linux/clockchips.h>
#include <asm/mach/time.h>
+#include <asm/sched_clock.h>
#include <mach/hardware.h>
+/*
+ * This is the SA11x0 sched_clock implementation.
+ */
+static DEFINE_CLOCK_DATA(cd);
+
+/*
+ * Constants generated by clocks_calc_mult_shift(m, s, 3.6864MHz,
+ * NSEC_PER_SEC, 60).
+ * This gives a resolution of about 271ns and a wrap period of about 19min.
+ */
+#define SC_MULT 2275555556u
+#define SC_SHIFT 23
+
+unsigned long long notrace sched_clock(void)
+{
+ u32 cyc = OSCR;
+ return cyc_to_fixed_sched_clock(&cd, cyc, (u32)~0, SC_MULT, SC_SHIFT);
+}
+
+static void notrace sa1100_update_sched_clock(void)
+{
+ u32 cyc = OSCR;
+ update_sched_clock(&cd, cyc, (u32)~0);
+}
+
#define MIN_OSCR_DELTA 2
static irqreturn_t sa1100_ost0_interrupt(int irq, void *dev_id)
@@ -81,7 +108,6 @@ static struct clocksource cksrc_sa1100_oscr = {
.rating = 200,
.read = sa1100_read_oscr,
.mask = CLOCKSOURCE_MASK(32),
- .shift = 20,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
@@ -97,6 +123,9 @@ static void __init sa1100_timer_init(void)
OIER = 0; /* disable any timer interrupts */
OSSR = 0xf; /* clear status on all timers */
+ init_fixed_sched_clock(&cd, sa1100_update_sched_clock, 32,
+ 3686400, SC_MULT, SC_SHIFT);
+
ckevt_sa1100_osmr0.mult =
div_sc(3686400, NSEC_PER_SEC, ckevt_sa1100_osmr0.shift);
ckevt_sa1100_osmr0.max_delta_ns =
@@ -105,12 +134,9 @@ static void __init sa1100_timer_init(void)
clockevent_delta2ns(MIN_OSCR_DELTA * 2, &ckevt_sa1100_osmr0) + 1;
ckevt_sa1100_osmr0.cpumask = cpumask_of(0);
- cksrc_sa1100_oscr.mult =
- clocksource_hz2mult(CLOCK_TICK_RATE, cksrc_sa1100_oscr.shift);
-
setup_irq(IRQ_OST0, &sa1100_timer_irq);
- clocksource_register(&cksrc_sa1100_oscr);
+ clocksource_register_hz(&cksrc_sa1100_oscr, CLOCK_TICK_RATE);
clockevents_register_device(&ckevt_sa1100_osmr0);
}