---

yaml
---
r: 191786
b: refs/heads/master
c: 2a84751
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: af7dc2281fd3cedc04cb51bcc0887cdaf65c3fcc
+refs/heads/master: 2a847513cdecd517f7efc06296c539c3a936cf98

trunk/arch/arm/plat-nomadik/timer.c

@@ -20,6 +20,15 @@
 
 void __iomem *mtu_base; /* ssigned by machine code */
 
+/*
+ * Kernel assumes that sched_clock can be called early
+ * but the MTU may not yet be initialized.
+ */
+static cycle_t nmdk_read_timer_dummy(struct clocksource *cs)
+{
+	return 0;
+}
+
 /* clocksource: MTU decrements, so we negate the value being read. */
 static cycle_t nmdk_read_timer(struct clocksource *cs)
 {
@@ -29,12 +38,27 @@ static cycle_t nmdk_read_timer(struct clocksource *cs)
 static struct clocksource nmdk_clksrc = {
 	.name		= "mtu_0",
 	.rating		= 200,
-	.read		= nmdk_read_timer,
+	.read		= nmdk_read_timer_dummy,
 	.mask		= CLOCKSOURCE_MASK(32),
 	.shift		= 20,
 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
 };
 
+/*
+ * Override the global weak sched_clock symbol with this
+ * local implementation which uses the clocksource to get some
+ * better resolution when scheduling the kernel. We accept that
+ * this wraps around for now, since it is just a relative time
+ * stamp. (Inspired by OMAP implementation.)
+ */
+unsigned long long notrace sched_clock(void)
+{
+	return clocksource_cyc2ns(nmdk_clksrc.read(
+				  &nmdk_clksrc),
+				  nmdk_clksrc.mult,
+				  nmdk_clksrc.shift);
+}
+
 /* Clockevent device: use one-shot mode */
 static void nmdk_clkevt_mode(enum clock_event_mode mode,
 			     struct clock_event_device *dev)
@@ -121,6 +145,8 @@ void __init nmdk_timer_init(void)
 	writel(cr | MTU_CRn_ENA, mtu_base + MTU_CR(0));
 
 	nmdk_clksrc.mult = clocksource_hz2mult(rate, nmdk_clksrc.shift);
+	/* Now the scheduling clock is ready */
+	nmdk_clksrc.read = nmdk_read_timer;
 
 	if (clocksource_register(&nmdk_clksrc))
 		pr_err("timer: failed to initialize clock source %s\n",