Commit e4752dbb authored by Andrew Bresticker's avatar Andrew Bresticker Committed by Ralf Baechle
Browse files

clocksource: mips-gic: Use CPU notifiers to setup the timer 



Instead of requiring an explicit call to gic_clockevent_init in the SMP
startup path, use CPU notifiers to register and enable the GIC timer on
CPU startup.

Signed-off-by: default avatarAndrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8139/


Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent f7ea3060

arch/mips/include/asm/time.h

+1 −4
Original line number Diff line number Diff line
@@ -53,13 +53,10 @@ extern int __weak get_c0_perfcount_int(void); 
 */

extern unsigned int __weak get_c0_compare_int(void);

extern int r4k_clockevent_init(void);

extern int gic_clockevent_init(void);



static inline int mips_clockevent_init(void)

{

#if   defined(CONFIG_CLKSRC_MIPS_GIC)

	return (gic_clockevent_init() | r4k_clockevent_init());

#elif defined(CONFIG_CEVT_R4K)

#ifdef CONFIG_CEVT_R4K

	return r4k_clockevent_init();

#else

	return -ENXIO;

drivers/clocksource/mips-gic-timer.c

+44 −16
Original line number Diff line number Diff line
@@ -6,9 +6,11 @@ 
 * Copyright (C) 2012 MIPS Technologies, Inc.  All rights reserved.

 */

#include <linux/clockchips.h>

#include <linux/cpu.h>

#include <linux/init.h>

#include <linux/interrupt.h>

#include <linux/irqchip/mips-gic.h>

#include <linux/notifier.h>

#include <linux/percpu.h>

#include <linux/smp.h>

#include <linux/time.h>
@@ -16,7 +18,7 @@ 
#include <asm/time.h>



static DEFINE_PER_CPU(struct clock_event_device, gic_clockevent_device);

static int gic_timer_irq_installed;

static int gic_timer_irq;

static unsigned int gic_frequency;



static int gic_next_event(unsigned long delta, struct clock_event_device *evt)
@@ -53,18 +55,9 @@ struct irqaction gic_compare_irqaction = { 
	.name = "timer",

};



int gic_clockevent_init(void)

static void gic_clockevent_cpu_init(struct clock_event_device *cd)

{

	unsigned int cpu = smp_processor_id();

	struct clock_event_device *cd;

	unsigned int irq;



	if (!cpu_has_counter || !gic_frequency)

		return -ENXIO;



	irq = MIPS_GIC_IRQ_BASE + GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_COMPARE);



	cd = &per_cpu(gic_clockevent_device, cpu);



	cd->name		= "MIPS GIC";

	cd->features		= CLOCK_EVT_FEAT_ONESHOT |
@@ -77,19 +70,52 @@ int gic_clockevent_init(void) 
	cd->min_delta_ns	= clockevent_delta2ns(0x300, cd);



	cd->rating		= 300;

	cd->irq			= irq;

	cd->irq			= gic_timer_irq;

	cd->cpumask		= cpumask_of(cpu);

	cd->set_next_event	= gic_next_event;

	cd->set_mode		= gic_set_clock_mode;



	clockevents_register_device(cd);



	if (!gic_timer_irq_installed) {

		setup_percpu_irq(irq, &gic_compare_irqaction);

		gic_timer_irq_installed = 1;

	enable_percpu_irq(gic_timer_irq, IRQ_TYPE_NONE);

}



static void gic_clockevent_cpu_exit(struct clock_event_device *cd)

{

	disable_percpu_irq(gic_timer_irq);

}



static int gic_cpu_notifier(struct notifier_block *nb, unsigned long action,

				void *data)

{

	switch (action & ~CPU_TASKS_FROZEN) {

	case CPU_STARTING:

		gic_clockevent_cpu_init(this_cpu_ptr(&gic_clockevent_device));

		break;

	case CPU_DYING:

		gic_clockevent_cpu_exit(this_cpu_ptr(&gic_clockevent_device));

		break;

	}



	return NOTIFY_OK;

}



	enable_percpu_irq(irq, IRQ_TYPE_NONE);

static struct notifier_block gic_cpu_nb = {

	.notifier_call = gic_cpu_notifier,

};



static int gic_clockevent_init(void)

{

	if (!cpu_has_counter || !gic_frequency)

		return -ENXIO;



	gic_timer_irq = MIPS_GIC_IRQ_BASE +

		GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_COMPARE);

	setup_percpu_irq(gic_timer_irq, &gic_compare_irqaction);



	register_cpu_notifier(&gic_cpu_nb);



	gic_clockevent_cpu_init(this_cpu_ptr(&gic_clockevent_device));



	return 0;

}
@@ -116,4 +142,6 @@ void __init gic_clocksource_init(unsigned int frequency) 
	gic_clocksource.rating = 200 + frequency / 10000000;



	clocksource_register_hz(&gic_clocksource, frequency);



	gic_clockevent_init();

}

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