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Commit 7ce83018 authored by Russell King's avatar Russell King
Browse files

ARM: pxa: convert sched_clock() to use new infrastructure 



Convert pxa to use the new sched_clock() infrastructure for extending
32bit counters to full 64-bit nanoseconds.

Tested-by: default avatarEric Miao <eric.y.miao@gmail.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 28bb7bc6

arch/arm/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -593,6 +593,7 @@ config ARCH_PXA 
	select COMMON_CLKDEV

	select ARCH_REQUIRE_GPIOLIB

	select GENERIC_CLOCKEVENTS

	select HAVE_SCHED_CLOCK

	select TICK_ONESHOT

	select PLAT_PXA

	select SPARSE_IRQ

arch/arm/mach-pxa/time.c

+9 −20
Original line number Diff line number Diff line
@@ -17,11 +17,11 @@ 
#include <linux/interrupt.h>

#include <linux/clockchips.h>

#include <linux/sched.h>

#include <linux/cnt32_to_63.h>



#include <asm/div64.h>

#include <asm/mach/irq.h>

#include <asm/mach/time.h>

#include <asm/sched_clock.h>

#include <mach/regs-ost.h>



/*
@@ -32,29 +32,18 @@ 
 * long as there is always less than 582 seconds between successive

 * calls to sched_clock() which should always be the case in practice.

 */

static DEFINE_CLOCK_DATA(cd);



#define OSCR2NS_SCALE_FACTOR 10



static unsigned long oscr2ns_scale;



static void __init set_oscr2ns_scale(unsigned long oscr_rate)

unsigned long long notrace sched_clock(void)

{

	unsigned long long v = 1000000000ULL << OSCR2NS_SCALE_FACTOR;

	do_div(v, oscr_rate);

	oscr2ns_scale = v;

	/*

	 * We want an even value to automatically clear the top bit

	 * returned by cnt32_to_63() without an additional run time

	 * instruction. So if the LSB is 1 then round it up.

	 */

	if (oscr2ns_scale & 1)

		oscr2ns_scale++;

	u32 cyc = OSCR;

	return cyc_to_sched_clock(&cd, cyc, (u32)~0);

}



unsigned long long notrace sched_clock(void)

static void notrace pxa_update_sched_clock(void)

{

	unsigned long long v = cnt32_to_63(OSCR);

	return (v * oscr2ns_scale) >> OSCR2NS_SCALE_FACTOR;

	u32 cyc = OSCR;

	update_sched_clock(&cd, cyc, (u32)~0);

}
@@ -144,7 +133,7 @@ static void __init pxa_timer_init(void) 
	OIER = 0;

	OSSR = OSSR_M0 | OSSR_M1 | OSSR_M2 | OSSR_M3;



	set_oscr2ns_scale(clock_tick_rate);

	init_sched_clock(&cd, pxa_update_sched_clock, 32, clock_tick_rate);



	ckevt_pxa_osmr0.mult =

		div_sc(clock_tick_rate, NSEC_PER_SEC, ckevt_pxa_osmr0.shift);