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arm_pmu: explicitly enable/disable SPIs at hotplug 

To support ACPI systems, we need to request IRQs before CPUs are
hotplugged, and thus we need to request IRQs before we know their
associated PMU.

This is problematic if a PMU IRQ is pending out of reset, as it may be
taken before we know the PMU, and thus the IRQ handler won't be able to
handle it, leaving it screaming.

To avoid such problems, lets request all IRQs in a disabled state, and
explicitly enable/disable them at hotplug time, when we're sure the PMU
has been probed.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
hifive-unleashed-5.1
Mark Rutland 2018-02-05 16:42:00 +00:00 committed by Will Deacon
parent 43fc9a2feb
commit 6de3f79112
1 changed files with 10 additions and 5 deletions
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15
drivers/perf/arm_pmu.c
View File

@ -558,6 +558,7 @@ int armpmu_request_irq(struct arm_pmu *armpmu, int cpu)
IRQF_NOBALANCING |
IRQF_NO_THREAD;
irq_set_status_flags(irq, IRQ_NOAUTOEN);
err = request_irq(irq, handler, irq_flags, "arm-pmu",
per_cpu_ptr(&hw_events->percpu_pmu, cpu));
} else if (cpumask_empty(&armpmu->active_irqs)) {
@ -600,10 +601,10 @@ static int arm_perf_starting_cpu(unsigned int cpu, struct hlist_node *node)
irq = armpmu_get_cpu_irq(pmu, cpu);
if (irq) {
if (irq_is_percpu_devid(irq)) {
if (irq_is_percpu_devid(irq))
enable_percpu_irq(irq, IRQ_TYPE_NONE);
return 0;
}
else
enable_irq(irq);
}
return 0;
@ -618,8 +619,12 @@ static int arm_perf_teardown_cpu(unsigned int cpu, struct hlist_node *node)
return 0;
irq = armpmu_get_cpu_irq(pmu, cpu);
if (irq && irq_is_percpu_devid(irq))
disable_percpu_irq(irq);
if (irq) {
if (irq_is_percpu_devid(irq))
disable_percpu_irq(irq);
else
disable_irq(irq);
}
return 0;
}