From e4752dbbc300939e14029583ba2a0b235b147649 Mon Sep 17 00:00:00 2001 From: Andrew Bresticker Date: Mon, 20 Oct 2014 12:04:04 -0700 Subject: [PATCH] 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: Andrew Bresticker Cc: Daniel Lezcano Cc: Thomas Gleixner Cc: Jason Cooper Cc: Paul Burton Cc: Qais Yousef Cc: John Crispin Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/8139/ Signed-off-by: Ralf Baechle --- arch/mips/include/asm/time.h | 5 +-- drivers/clocksource/mips-gic-timer.c | 60 ++++++++++++++++++++++++++---------- 2 files changed, 45 insertions(+), 20 deletions(-) diff --git a/arch/mips/include/asm/time.h b/arch/mips/include/asm/time.h index 5f30aab..8ab2874 100644 --- a/arch/mips/include/asm/time.h +++ b/arch/mips/include/asm/time.h @@ -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; diff --git a/drivers/clocksource/mips-gic-timer.c b/drivers/clocksource/mips-gic-timer.c index 05bdfe1..3ce992b 100644 --- a/drivers/clocksource/mips-gic-timer.c +++ b/drivers/clocksource/mips-gic-timer.c @@ -6,9 +6,11 @@ * Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved. */ #include +#include #include #include #include +#include #include #include #include @@ -16,7 +18,7 @@ #include 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; } - enable_percpu_irq(irq, IRQ_TYPE_NONE); + return NOTIFY_OK; +} + +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(); } -- 2.7.4