From 201d7f47f34bd7cb19161d0426f13b141e381f30 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 31 May 2017 11:58:32 +0200 Subject: [PATCH] genirq: Handle NOAUTOEN interrupt setup proper If an interrupt is marked NOAUTOEN then request_irq() installs the action, but does not enable the interrupt via startup_irq(). The interrupt is enabled via enable_irq() later from the driver. enable_irq() calls irq_enable(). That means that for interrupts which have a irq_startup() callback this callback is never invoked. Neither is irq_domain_activate_irq() invoked for such interrupts. If an interrupt depends on irq_startup() or irq_domain_activate_irq() then the enable via irq_enable() is not enough. Add a status flag IRQD_IRQ_STARTED_UP and use this to select the proper mechanism in enable_irq(). Use the flag also to avoid pointless calls into the low level functions. Signed-off-by: Thomas Gleixner Acked-by: Marc Zyngier Cc: dianders@chromium.org Cc: jeffy Cc: Brian Norris Cc: tfiga@chromium.org Link: http://lkml.kernel.org/r/20170531100212.130986205@linutronix.de --- include/linux/irq.h | 6 ++++ kernel/irq/chip.c | 76 ++++++++++++++++++++++++++++++++------------- kernel/irq/manage.c | 12 +++++-- 3 files changed, 69 insertions(+), 25 deletions(-) diff --git a/include/linux/irq.h b/include/linux/irq.h index f887351aa80e..94d1ad6ffdd4 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -216,6 +216,7 @@ enum { IRQD_WAKEUP_ARMED = (1 << 19), IRQD_FORWARDED_TO_VCPU = (1 << 20), IRQD_AFFINITY_MANAGED = (1 << 21), + IRQD_IRQ_STARTED = (1 << 22), }; #define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors) @@ -329,6 +330,11 @@ static inline void irqd_clr_activated(struct irq_data *d) __irqd_to_state(d) &= ~IRQD_ACTIVATED; } +static inline bool irqd_is_started(struct irq_data *d) +{ + return __irqd_to_state(d) & IRQD_IRQ_STARTED; +} + #undef __irqd_to_state static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d) diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index c94da688ee9b..e0051d58c909 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -185,37 +185,64 @@ static void irq_state_set_masked(struct irq_desc *desc) irqd_set(&desc->irq_data, IRQD_IRQ_MASKED); } +static void irq_state_clr_started(struct irq_desc *desc) +{ + irqd_clear(&desc->irq_data, IRQD_IRQ_STARTED); +} + +static void irq_state_set_started(struct irq_desc *desc) +{ + irqd_set(&desc->irq_data, IRQD_IRQ_STARTED); +} + int irq_startup(struct irq_desc *desc, bool resend) { int ret = 0; - irq_state_clr_disabled(desc); desc->depth = 0; - irq_domain_activate_irq(&desc->irq_data); - if (desc->irq_data.chip->irq_startup) { - ret = desc->irq_data.chip->irq_startup(&desc->irq_data); - irq_state_clr_masked(desc); - } else { + if (irqd_is_started(&desc->irq_data)) { irq_enable(desc); + } else { + irq_domain_activate_irq(&desc->irq_data); + if (desc->irq_data.chip->irq_startup) { + ret = desc->irq_data.chip->irq_startup(&desc->irq_data); + irq_state_clr_disabled(desc); + irq_state_clr_masked(desc); + } else { + irq_enable(desc); + } + irq_state_set_started(desc); } + if (resend) check_irq_resend(desc); + return ret; } +static void __irq_disable(struct irq_desc *desc, bool mask); + void irq_shutdown(struct irq_desc *desc) { - irq_state_set_disabled(desc); - desc->depth = 1; - if (desc->irq_data.chip->irq_shutdown) - desc->irq_data.chip->irq_shutdown(&desc->irq_data); - else if (desc->irq_data.chip->irq_disable) - desc->irq_data.chip->irq_disable(&desc->irq_data); - else - desc->irq_data.chip->irq_mask(&desc->irq_data); + if (irqd_is_started(&desc->irq_data)) { + desc->depth = 1; + if (desc->irq_data.chip->irq_shutdown) { + desc->irq_data.chip->irq_shutdown(&desc->irq_data); + irq_state_set_disabled(desc); + irq_state_set_masked(desc); + } else { + __irq_disable(desc, true); + } + irq_state_clr_started(desc); + } + /* + * This must be called even if the interrupt was never started up, + * because the activation can happen before the interrupt is + * available for request/startup. It has it's own state tracking so + * it's safe to call it unconditionally. + */ irq_domain_deactivate_irq(&desc->irq_data); - irq_state_set_masked(desc); } void irq_enable(struct irq_desc *desc) @@ -228,6 +255,17 @@ void irq_enable(struct irq_desc *desc) irq_state_clr_masked(desc); } +static void __irq_disable(struct irq_desc *desc, bool mask) +{ + irq_state_set_disabled(desc); + if (desc->irq_data.chip->irq_disable) { + desc->irq_data.chip->irq_disable(&desc->irq_data); + irq_state_set_masked(desc); + } else if (mask) { + mask_irq(desc); + } +} + /** * irq_disable - Mark interrupt disabled * @desc: irq descriptor which should be disabled @@ -250,13 +288,7 @@ void irq_enable(struct irq_desc *desc) */ void irq_disable(struct irq_desc *desc) { - irq_state_set_disabled(desc); - if (desc->irq_data.chip->irq_disable) { - desc->irq_data.chip->irq_disable(&desc->irq_data); - irq_state_set_masked(desc); - } else if (irq_settings_disable_unlazy(desc)) { - mask_irq(desc); - } + __irq_disable(desc, irq_settings_disable_unlazy(desc)); } void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu) diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 070be980c37a..57056109f176 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -533,9 +533,15 @@ void __enable_irq(struct irq_desc *desc) goto err_out; /* Prevent probing on this irq: */ irq_settings_set_noprobe(desc); - irq_enable(desc); - check_irq_resend(desc); - /* fall-through */ + /* + * Call irq_startup() not irq_enable() here because the + * interrupt might be marked NOAUTOEN. So irq_startup() + * needs to be invoked when it gets enabled the first + * time. If it was already started up, then irq_startup() + * will invoke irq_enable() under the hood. + */ + irq_startup(desc, true); + break; } default: desc->depth--; -- 2.20.1