@@ -272,15 +272,35 @@ static cycle_t read_cycles(struct clocksource *cs)
return (cycles_t)timer32_read(t);
}
+/*
+ * Kernel assumes that sched_clock can be called early but may not have
+ * things ready yet.
+ */
+static cycle_t read_dummy(struct clocksource *cs)
+{
+ return 0;
+}
+
+
static struct clocksource clocksource_davinci = {
.rating = 300,
- .read = read_cycles,
+ .read = read_dummy,
.mask = CLOCKSOURCE_MASK(32),
.shift = 24,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
/*
+ * Overwrite weak default sched_clock with something more precise
+ */
+unsigned long long notrace sched_clock(void)
+{
+ const cycle_t cyc = clocksource_davinci.read(&clocksource_davinci);
+ return clocksource_cyc2ns(cyc, clocksource_davinci.mult,
+ clocksource_davinci.shift);
+}
+
+/*
* clockevent
*/
static int davinci_set_next_event(unsigned long cycles,
@@ -377,6 +397,7 @@ static void __init davinci_timer_init(void)
davinci_clock_tick_rate = clk_get_rate(timer_clk);
/* setup clocksource */
+ clocksource_davinci.read = read_cycles;
clocksource_davinci.name = id_to_name[clocksource_id];
clocksource_davinci.mult =
clocksource_khz2mult(davinci_clock_tick_rate/1000,