ARM: sa1100: convert sched_clock() to use new infrastructure
Convert sa1100 to use the new sched_clock() infrastructure for extending
32bit counters to full 64-bit nanoseconds.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-sa1100/time.c b/arch/arm/mach-sa1100/time.c
index 96154f5..ae4f3d8 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)
@@ -96,6 +123,9 @@
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 =