---

yaml --- r: 225838 b: refs/heads/master c: 5094b92 h: refs/heads/master v: v3
git-mirror · Dec 22, 2010 · d847d91 · d847d91
1 parent 3192c4d
commit d847d91
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Showing 4 changed files with 32 additions and 24 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7ce830188199c23aaeaf0c5ccc28b73c32b6df02
+refs/heads/master: 5094b92f1c7d0f21c5d4411ba7415bac0684210f
diff --git a/trunk/arch/arm/Kconfig b/trunk/arch/arm/Kconfig
@@ -642,6 +642,7 @@ config ARCH_SA1100
 	select CPU_FREQ
 	select GENERIC_CLOCKEVENTS
 	select HAVE_CLK
+	select HAVE_SCHED_CLOCK
 	select TICK_ONESHOT
 	select ARCH_REQUIRE_GPIOLIB
 	help

diff --git a/trunk/arch/arm/mach-sa1100/generic.c b/trunk/arch/arm/mach-sa1100/generic.c
@@ -16,9 +16,7 @@
 #include <linux/pm.h>
 #include <linux/cpufreq.h>
 #include <linux/ioport.h>
-#include <linux/sched.h>	/* just for sched_clock() - funny that */
 #include <linux/platform_device.h>
-#include <linux/cnt32_to_63.h>
 
 #include <asm/div64.h>
 #include <mach/hardware.h>
@@ -109,27 +107,6 @@ unsigned int sa11x0_getspeed(unsigned int cpu)
 	return cclk_frequency_100khz[PPCR & 0xf] * 100;
 }
 
-/*
- * This is the SA11x0 sched_clock implementation.  This has
- * 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 notrace sched_clock(void)
-{
-	unsigned long long v = cnt32_to_63(OSCR);
-
-	/* 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;
-}
-
 /*
  * Default power-off for SA1100
  */

diff --git a/trunk/arch/arm/mach-sa1100/time.c b/trunk/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 @@ 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 =