[patch 43/66] clocksource/armada-370-xp: Convert to hotplug state machine
From: Anna-Maria Gleixner <anna-maria@linutronix.de>
Date: 2016-07-11 12:38:45
From: Richard Cochran <redacted> Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Daniel Lezcano <redacted> --- drivers/clocksource/time-armada-370-xp.c | 44 +++++++++---------------------- include/linux/cpuhotplug.h | 1 2 files changed, 15 insertions(+), 30 deletions(-)
--- a/drivers/clocksource/time-armada-370-xp.c
+++ b/drivers/clocksource/time-armada-370-xp.c@@ -170,10 +170,10 @@ static irqreturn_t armada_370_xp_timer_i /* * Setup the local clock events for a CPU. */ -static int armada_370_xp_timer_setup(struct clock_event_device *evt) +static int armada_370_xp_timer_starting_cpu(unsigned int cpu) { + struct clock_event_device *evt = per_cpu_ptr(armada_370_xp_evt, cpu); u32 clr = 0, set = 0; - int cpu = smp_processor_id(); if (timer25Mhz) set = TIMER0_25MHZ;
@@ -200,35 +200,15 @@ static int armada_370_xp_timer_setup(str return 0; } -static void armada_370_xp_timer_stop(struct clock_event_device *evt) +static int armada_370_xp_timer_dying_cpu(unsigned int cpu) { + struct clock_event_device *evt = per_cpu_ptr(armada_370_xp_evt, cpu); + evt->set_state_shutdown(evt); disable_percpu_irq(evt->irq); + return 0; } -static int armada_370_xp_timer_cpu_notify(struct notifier_block *self, - unsigned long action, void *hcpu) -{ - /* - * Grab cpu pointer in each case to avoid spurious - * preemptible warnings - */ - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_STARTING: - armada_370_xp_timer_setup(this_cpu_ptr(armada_370_xp_evt)); - break; - case CPU_DYING: - armada_370_xp_timer_stop(this_cpu_ptr(armada_370_xp_evt)); - break; - } - - return NOTIFY_OK; -} - -static struct notifier_block armada_370_xp_timer_cpu_nb = { - .notifier_call = armada_370_xp_timer_cpu_notify, -}; - static u32 timer0_ctrl_reg, timer0_local_ctrl_reg; static int armada_370_xp_timer_suspend(void)
@@ -310,8 +290,6 @@ static void __init armada_370_xp_timer_c "armada_370_xp_clocksource", timer_clk, 300, 32, clocksource_mmio_readl_down); - register_cpu_notifier(&armada_370_xp_timer_cpu_nb); - armada_370_xp_evt = alloc_percpu(struct clock_event_device);
@@ -323,8 +301,14 @@ static void __init armada_370_xp_timer_c "armada_370_xp_per_cpu_tick", armada_370_xp_evt); /* Immediately configure the timer on the boot CPU */ - if (!res) - armada_370_xp_timer_setup(this_cpu_ptr(armada_370_xp_evt)); + if (res) { + pr_err("armada_370_xp_timer: failed to register per-cpu IRQ\n"); + } else { + cpuhp_setup_state(CPUHP_AP_ARMADA_TIMER_STARTING, + "AP_ARMADA_TIMER_STARTING", + armada_370_xp_timer_starting_cpu, + armada_370_xp_timer_dying_cpu); + } register_syscore_ops(&armada_370_xp_timer_syscore_ops); } --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h
@@ -43,6 +43,7 @@ enum cpuhp_state { CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING, CPUHP_AP_METAG_TIMER_STARTING, CPUHP_AP_QCOM_TIMER_STARTING, + CPUHP_AP_ARMADA_TIMER_STARTING, CPUHP_AP_KVM_STARTING, CPUHP_AP_NOTIFY_STARTING, CPUHP_AP_ONLINE,