Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 6d1c57c8 authored by Andreas Gaeer's avatar Andreas Gaeer Committed by Kevin Hilman
Browse files

davinci: Implement sched_clock() 



Overwrite the default implementation of sched_clock that is based on
jiffies by something more precise. This improves timestamps in ftrace.
Implementation is copied from OMAP platform code.

Signed-off-by: default avatarAndreas Gaeer <Andreas.Gaer@baslerweb.com>
Signed-off-by: default avatarKevin Hilman <khilman@deeprootsystems.com>
parent cf7d7e5a

arch/arm/mach-davinci/time.c

+23 −1
Original line number Diff line number Diff line
@@ -272,14 +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

 */
@@ -377,6 +398,7 @@ 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,