1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
4 * Copyright (C) 2005-2006 Thomas Gleixner
6 * This file contains driver APIs to the irq subsystem.
9 #define pr_fmt(fmt) "genirq: " fmt
11 #include <linux/irq.h>
12 #include <linux/kthread.h>
13 #include <linux/module.h>
14 #include <linux/random.h>
15 #include <linux/interrupt.h>
16 #include <linux/irqdomain.h>
17 #include <linux/slab.h>
18 #include <linux/sched.h>
19 #include <linux/sched/rt.h>
20 #include <linux/sched/task.h>
21 #include <linux/sched/isolation.h>
22 #include <uapi/linux/sched/types.h>
23 #include <linux/task_work.h>
25 #include "internals.h"
27 #if defined(CONFIG_IRQ_FORCED_THREADING) && !defined(CONFIG_PREEMPT_RT)
28 DEFINE_STATIC_KEY_FALSE(force_irqthreads_key);
30 static int __init setup_forced_irqthreads(char *arg)
32 static_branch_enable(&force_irqthreads_key);
35 early_param("threadirqs", setup_forced_irqthreads);
38 static void __synchronize_hardirq(struct irq_desc *desc, bool sync_chip)
40 struct irq_data *irqd = irq_desc_get_irq_data(desc);
47 * Wait until we're out of the critical section. This might
48 * give the wrong answer due to the lack of memory barriers.
50 while (irqd_irq_inprogress(&desc->irq_data))
53 /* Ok, that indicated we're done: double-check carefully. */
54 raw_spin_lock_irqsave(&desc->lock, flags);
55 inprogress = irqd_irq_inprogress(&desc->irq_data);
58 * If requested and supported, check at the chip whether it
59 * is in flight at the hardware level, i.e. already pending
60 * in a CPU and waiting for service and acknowledge.
62 if (!inprogress && sync_chip) {
64 * Ignore the return code. inprogress is only updated
65 * when the chip supports it.
67 __irq_get_irqchip_state(irqd, IRQCHIP_STATE_ACTIVE,
70 raw_spin_unlock_irqrestore(&desc->lock, flags);
72 /* Oops, that failed? */
77 * synchronize_hardirq - wait for pending hard IRQ handlers (on other CPUs)
78 * @irq: interrupt number to wait for
80 * This function waits for any pending hard IRQ handlers for this
81 * interrupt to complete before returning. If you use this
82 * function while holding a resource the IRQ handler may need you
83 * will deadlock. It does not take associated threaded handlers
86 * Do not use this for shutdown scenarios where you must be sure
87 * that all parts (hardirq and threaded handler) have completed.
89 * Returns: false if a threaded handler is active.
91 * This function may be called - with care - from IRQ context.
93 * It does not check whether there is an interrupt in flight at the
94 * hardware level, but not serviced yet, as this might deadlock when
95 * called with interrupts disabled and the target CPU of the interrupt
98 bool synchronize_hardirq(unsigned int irq)
100 struct irq_desc *desc = irq_to_desc(irq);
103 __synchronize_hardirq(desc, false);
104 return !atomic_read(&desc->threads_active);
109 EXPORT_SYMBOL(synchronize_hardirq);
112 * synchronize_irq - wait for pending IRQ handlers (on other CPUs)
113 * @irq: interrupt number to wait for
115 * This function waits for any pending IRQ handlers for this interrupt
116 * to complete before returning. If you use this function while
117 * holding a resource the IRQ handler may need you will deadlock.
119 * Can only be called from preemptible code as it might sleep when
120 * an interrupt thread is associated to @irq.
122 * It optionally makes sure (when the irq chip supports that method)
123 * that the interrupt is not pending in any CPU and waiting for
126 void synchronize_irq(unsigned int irq)
128 struct irq_desc *desc = irq_to_desc(irq);
131 __synchronize_hardirq(desc, true);
133 * We made sure that no hardirq handler is
134 * running. Now verify that no threaded handlers are
137 wait_event(desc->wait_for_threads,
138 !atomic_read(&desc->threads_active));
141 EXPORT_SYMBOL(synchronize_irq);
144 cpumask_var_t irq_default_affinity;
146 static bool __irq_can_set_affinity(struct irq_desc *desc)
148 if (!desc || !irqd_can_balance(&desc->irq_data) ||
149 !desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity)
155 * irq_can_set_affinity - Check if the affinity of a given irq can be set
156 * @irq: Interrupt to check
159 int irq_can_set_affinity(unsigned int irq)
161 return __irq_can_set_affinity(irq_to_desc(irq));
165 * irq_can_set_affinity_usr - Check if affinity of a irq can be set from user space
166 * @irq: Interrupt to check
168 * Like irq_can_set_affinity() above, but additionally checks for the
169 * AFFINITY_MANAGED flag.
171 bool irq_can_set_affinity_usr(unsigned int irq)
173 struct irq_desc *desc = irq_to_desc(irq);
175 return __irq_can_set_affinity(desc) &&
176 !irqd_affinity_is_managed(&desc->irq_data);
180 * irq_set_thread_affinity - Notify irq threads to adjust affinity
181 * @desc: irq descriptor which has affinity changed
183 * We just set IRQTF_AFFINITY and delegate the affinity setting
184 * to the interrupt thread itself. We can not call
185 * set_cpus_allowed_ptr() here as we hold desc->lock and this
186 * code can be called from hard interrupt context.
188 void irq_set_thread_affinity(struct irq_desc *desc)
190 struct irqaction *action;
192 for_each_action_of_desc(desc, action) {
194 set_bit(IRQTF_AFFINITY, &action->thread_flags);
195 if (action->secondary && action->secondary->thread)
196 set_bit(IRQTF_AFFINITY, &action->secondary->thread_flags);
200 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
201 static void irq_validate_effective_affinity(struct irq_data *data)
203 const struct cpumask *m = irq_data_get_effective_affinity_mask(data);
204 struct irq_chip *chip = irq_data_get_irq_chip(data);
206 if (!cpumask_empty(m))
208 pr_warn_once("irq_chip %s did not update eff. affinity mask of irq %u\n",
209 chip->name, data->irq);
212 static inline void irq_validate_effective_affinity(struct irq_data *data) { }
215 int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
218 struct irq_desc *desc = irq_data_to_desc(data);
219 struct irq_chip *chip = irq_data_get_irq_chip(data);
220 const struct cpumask *prog_mask;
223 static DEFINE_RAW_SPINLOCK(tmp_mask_lock);
224 static struct cpumask tmp_mask;
226 if (!chip || !chip->irq_set_affinity)
229 raw_spin_lock(&tmp_mask_lock);
231 * If this is a managed interrupt and housekeeping is enabled on
232 * it check whether the requested affinity mask intersects with
233 * a housekeeping CPU. If so, then remove the isolated CPUs from
234 * the mask and just keep the housekeeping CPU(s). This prevents
235 * the affinity setter from routing the interrupt to an isolated
236 * CPU to avoid that I/O submitted from a housekeeping CPU causes
237 * interrupts on an isolated one.
239 * If the masks do not intersect or include online CPU(s) then
240 * keep the requested mask. The isolated target CPUs are only
241 * receiving interrupts when the I/O operation was submitted
242 * directly from them.
244 * If all housekeeping CPUs in the affinity mask are offline, the
245 * interrupt will be migrated by the CPU hotplug code once a
246 * housekeeping CPU which belongs to the affinity mask comes
249 if (irqd_affinity_is_managed(data) &&
250 housekeeping_enabled(HK_TYPE_MANAGED_IRQ)) {
251 const struct cpumask *hk_mask;
253 hk_mask = housekeeping_cpumask(HK_TYPE_MANAGED_IRQ);
255 cpumask_and(&tmp_mask, mask, hk_mask);
256 if (!cpumask_intersects(&tmp_mask, cpu_online_mask))
259 prog_mask = &tmp_mask;
265 * Make sure we only provide online CPUs to the irqchip,
266 * unless we are being asked to force the affinity (in which
267 * case we do as we are told).
269 cpumask_and(&tmp_mask, prog_mask, cpu_online_mask);
270 if (!force && !cpumask_empty(&tmp_mask))
271 ret = chip->irq_set_affinity(data, &tmp_mask, force);
273 ret = chip->irq_set_affinity(data, mask, force);
277 raw_spin_unlock(&tmp_mask_lock);
280 case IRQ_SET_MASK_OK:
281 case IRQ_SET_MASK_OK_DONE:
282 cpumask_copy(desc->irq_common_data.affinity, mask);
284 case IRQ_SET_MASK_OK_NOCOPY:
285 irq_validate_effective_affinity(data);
286 irq_set_thread_affinity(desc);
293 #ifdef CONFIG_GENERIC_PENDING_IRQ
294 static inline int irq_set_affinity_pending(struct irq_data *data,
295 const struct cpumask *dest)
297 struct irq_desc *desc = irq_data_to_desc(data);
299 irqd_set_move_pending(data);
300 irq_copy_pending(desc, dest);
304 static inline int irq_set_affinity_pending(struct irq_data *data,
305 const struct cpumask *dest)
311 static int irq_try_set_affinity(struct irq_data *data,
312 const struct cpumask *dest, bool force)
314 int ret = irq_do_set_affinity(data, dest, force);
317 * In case that the underlying vector management is busy and the
318 * architecture supports the generic pending mechanism then utilize
319 * this to avoid returning an error to user space.
321 if (ret == -EBUSY && !force)
322 ret = irq_set_affinity_pending(data, dest);
326 static bool irq_set_affinity_deactivated(struct irq_data *data,
327 const struct cpumask *mask)
329 struct irq_desc *desc = irq_data_to_desc(data);
332 * Handle irq chips which can handle affinity only in activated
335 * If the interrupt is not yet activated, just store the affinity
336 * mask and do not call the chip driver at all. On activation the
337 * driver has to make sure anyway that the interrupt is in a
338 * usable state so startup works.
340 if (!IS_ENABLED(CONFIG_IRQ_DOMAIN_HIERARCHY) ||
341 irqd_is_activated(data) || !irqd_affinity_on_activate(data))
344 cpumask_copy(desc->irq_common_data.affinity, mask);
345 irq_data_update_effective_affinity(data, mask);
346 irqd_set(data, IRQD_AFFINITY_SET);
350 int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
353 struct irq_chip *chip = irq_data_get_irq_chip(data);
354 struct irq_desc *desc = irq_data_to_desc(data);
357 if (!chip || !chip->irq_set_affinity)
360 if (irq_set_affinity_deactivated(data, mask))
363 if (irq_can_move_pcntxt(data) && !irqd_is_setaffinity_pending(data)) {
364 ret = irq_try_set_affinity(data, mask, force);
366 irqd_set_move_pending(data);
367 irq_copy_pending(desc, mask);
370 if (desc->affinity_notify) {
371 kref_get(&desc->affinity_notify->kref);
372 if (!schedule_work(&desc->affinity_notify->work)) {
373 /* Work was already scheduled, drop our extra ref */
374 kref_put(&desc->affinity_notify->kref,
375 desc->affinity_notify->release);
378 irqd_set(data, IRQD_AFFINITY_SET);
384 * irq_update_affinity_desc - Update affinity management for an interrupt
385 * @irq: The interrupt number to update
386 * @affinity: Pointer to the affinity descriptor
388 * This interface can be used to configure the affinity management of
389 * interrupts which have been allocated already.
391 * There are certain limitations on when it may be used - attempts to use it
392 * for when the kernel is configured for generic IRQ reservation mode (in
393 * config GENERIC_IRQ_RESERVATION_MODE) will fail, as it may conflict with
394 * managed/non-managed interrupt accounting. In addition, attempts to use it on
395 * an interrupt which is already started or which has already been configured
396 * as managed will also fail, as these mean invalid init state or double init.
398 int irq_update_affinity_desc(unsigned int irq,
399 struct irq_affinity_desc *affinity)
401 struct irq_desc *desc;
407 * Supporting this with the reservation scheme used by x86 needs
408 * some more thought. Fail it for now.
410 if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE))
413 desc = irq_get_desc_buslock(irq, &flags, 0);
417 /* Requires the interrupt to be shut down */
418 if (irqd_is_started(&desc->irq_data)) {
423 /* Interrupts which are already managed cannot be modified */
424 if (irqd_affinity_is_managed(&desc->irq_data)) {
430 * Deactivate the interrupt. That's required to undo
431 * anything an earlier activation has established.
433 activated = irqd_is_activated(&desc->irq_data);
435 irq_domain_deactivate_irq(&desc->irq_data);
437 if (affinity->is_managed) {
438 irqd_set(&desc->irq_data, IRQD_AFFINITY_MANAGED);
439 irqd_set(&desc->irq_data, IRQD_MANAGED_SHUTDOWN);
442 cpumask_copy(desc->irq_common_data.affinity, &affinity->mask);
444 /* Restore the activation state */
446 irq_domain_activate_irq(&desc->irq_data, false);
449 irq_put_desc_busunlock(desc, flags);
453 static int __irq_set_affinity(unsigned int irq, const struct cpumask *mask,
456 struct irq_desc *desc = irq_to_desc(irq);
463 raw_spin_lock_irqsave(&desc->lock, flags);
464 ret = irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask, force);
465 raw_spin_unlock_irqrestore(&desc->lock, flags);
470 * irq_set_affinity - Set the irq affinity of a given irq
471 * @irq: Interrupt to set affinity
474 * Fails if cpumask does not contain an online CPU
476 int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
478 return __irq_set_affinity(irq, cpumask, false);
480 EXPORT_SYMBOL_GPL(irq_set_affinity);
483 * irq_force_affinity - Force the irq affinity of a given irq
484 * @irq: Interrupt to set affinity
487 * Same as irq_set_affinity, but without checking the mask against
490 * Solely for low level cpu hotplug code, where we need to make per
491 * cpu interrupts affine before the cpu becomes online.
493 int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
495 return __irq_set_affinity(irq, cpumask, true);
497 EXPORT_SYMBOL_GPL(irq_force_affinity);
499 int __irq_apply_affinity_hint(unsigned int irq, const struct cpumask *m,
503 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
507 desc->affinity_hint = m;
508 irq_put_desc_unlock(desc, flags);
509 if (m && setaffinity)
510 __irq_set_affinity(irq, m, false);
513 EXPORT_SYMBOL_GPL(__irq_apply_affinity_hint);
515 static void irq_affinity_notify(struct work_struct *work)
517 struct irq_affinity_notify *notify =
518 container_of(work, struct irq_affinity_notify, work);
519 struct irq_desc *desc = irq_to_desc(notify->irq);
520 cpumask_var_t cpumask;
523 if (!desc || !alloc_cpumask_var(&cpumask, GFP_KERNEL))
526 raw_spin_lock_irqsave(&desc->lock, flags);
527 if (irq_move_pending(&desc->irq_data))
528 irq_get_pending(cpumask, desc);
530 cpumask_copy(cpumask, desc->irq_common_data.affinity);
531 raw_spin_unlock_irqrestore(&desc->lock, flags);
533 notify->notify(notify, cpumask);
535 free_cpumask_var(cpumask);
537 kref_put(¬ify->kref, notify->release);
541 * irq_set_affinity_notifier - control notification of IRQ affinity changes
542 * @irq: Interrupt for which to enable/disable notification
543 * @notify: Context for notification, or %NULL to disable
544 * notification. Function pointers must be initialised;
545 * the other fields will be initialised by this function.
547 * Must be called in process context. Notification may only be enabled
548 * after the IRQ is allocated and must be disabled before the IRQ is
549 * freed using free_irq().
552 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
554 struct irq_desc *desc = irq_to_desc(irq);
555 struct irq_affinity_notify *old_notify;
558 /* The release function is promised process context */
561 if (!desc || desc->istate & IRQS_NMI)
564 /* Complete initialisation of *notify */
567 kref_init(¬ify->kref);
568 INIT_WORK(¬ify->work, irq_affinity_notify);
571 raw_spin_lock_irqsave(&desc->lock, flags);
572 old_notify = desc->affinity_notify;
573 desc->affinity_notify = notify;
574 raw_spin_unlock_irqrestore(&desc->lock, flags);
577 if (cancel_work_sync(&old_notify->work)) {
578 /* Pending work had a ref, put that one too */
579 kref_put(&old_notify->kref, old_notify->release);
581 kref_put(&old_notify->kref, old_notify->release);
586 EXPORT_SYMBOL_GPL(irq_set_affinity_notifier);
588 #ifndef CONFIG_AUTO_IRQ_AFFINITY
590 * Generic version of the affinity autoselector.
592 int irq_setup_affinity(struct irq_desc *desc)
594 struct cpumask *set = irq_default_affinity;
595 int ret, node = irq_desc_get_node(desc);
596 static DEFINE_RAW_SPINLOCK(mask_lock);
597 static struct cpumask mask;
599 /* Excludes PER_CPU and NO_BALANCE interrupts */
600 if (!__irq_can_set_affinity(desc))
603 raw_spin_lock(&mask_lock);
605 * Preserve the managed affinity setting and a userspace affinity
606 * setup, but make sure that one of the targets is online.
608 if (irqd_affinity_is_managed(&desc->irq_data) ||
609 irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) {
610 if (cpumask_intersects(desc->irq_common_data.affinity,
612 set = desc->irq_common_data.affinity;
614 irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET);
617 cpumask_and(&mask, cpu_online_mask, set);
618 if (cpumask_empty(&mask))
619 cpumask_copy(&mask, cpu_online_mask);
621 if (node != NUMA_NO_NODE) {
622 const struct cpumask *nodemask = cpumask_of_node(node);
624 /* make sure at least one of the cpus in nodemask is online */
625 if (cpumask_intersects(&mask, nodemask))
626 cpumask_and(&mask, &mask, nodemask);
628 ret = irq_do_set_affinity(&desc->irq_data, &mask, false);
629 raw_spin_unlock(&mask_lock);
633 /* Wrapper for ALPHA specific affinity selector magic */
634 int irq_setup_affinity(struct irq_desc *desc)
636 return irq_select_affinity(irq_desc_get_irq(desc));
638 #endif /* CONFIG_AUTO_IRQ_AFFINITY */
639 #endif /* CONFIG_SMP */
643 * irq_set_vcpu_affinity - Set vcpu affinity for the interrupt
644 * @irq: interrupt number to set affinity
645 * @vcpu_info: vCPU specific data or pointer to a percpu array of vCPU
646 * specific data for percpu_devid interrupts
648 * This function uses the vCPU specific data to set the vCPU
649 * affinity for an irq. The vCPU specific data is passed from
650 * outside, such as KVM. One example code path is as below:
651 * KVM -> IOMMU -> irq_set_vcpu_affinity().
653 int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info)
656 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
657 struct irq_data *data;
658 struct irq_chip *chip;
664 data = irq_desc_get_irq_data(desc);
666 chip = irq_data_get_irq_chip(data);
667 if (chip && chip->irq_set_vcpu_affinity)
669 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
670 data = data->parent_data;
677 ret = chip->irq_set_vcpu_affinity(data, vcpu_info);
678 irq_put_desc_unlock(desc, flags);
682 EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity);
684 void __disable_irq(struct irq_desc *desc)
690 static int __disable_irq_nosync(unsigned int irq)
693 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
698 irq_put_desc_busunlock(desc, flags);
703 * disable_irq_nosync - disable an irq without waiting
704 * @irq: Interrupt to disable
706 * Disable the selected interrupt line. Disables and Enables are
708 * Unlike disable_irq(), this function does not ensure existing
709 * instances of the IRQ handler have completed before returning.
711 * This function may be called from IRQ context.
713 void disable_irq_nosync(unsigned int irq)
715 __disable_irq_nosync(irq);
717 EXPORT_SYMBOL(disable_irq_nosync);
720 * disable_irq - disable an irq and wait for completion
721 * @irq: Interrupt to disable
723 * Disable the selected interrupt line. Enables and Disables are
725 * This function waits for any pending IRQ handlers for this interrupt
726 * to complete before returning. If you use this function while
727 * holding a resource the IRQ handler may need you will deadlock.
729 * Can only be called from preemptible code as it might sleep when
730 * an interrupt thread is associated to @irq.
733 void disable_irq(unsigned int irq)
736 if (!__disable_irq_nosync(irq))
737 synchronize_irq(irq);
739 EXPORT_SYMBOL(disable_irq);
742 * disable_hardirq - disables an irq and waits for hardirq completion
743 * @irq: Interrupt to disable
745 * Disable the selected interrupt line. Enables and Disables are
747 * This function waits for any pending hard IRQ handlers for this
748 * interrupt to complete before returning. If you use this function while
749 * holding a resource the hard IRQ handler may need you will deadlock.
751 * When used to optimistically disable an interrupt from atomic context
752 * the return value must be checked.
754 * Returns: false if a threaded handler is active.
756 * This function may be called - with care - from IRQ context.
758 bool disable_hardirq(unsigned int irq)
760 if (!__disable_irq_nosync(irq))
761 return synchronize_hardirq(irq);
765 EXPORT_SYMBOL_GPL(disable_hardirq);
768 * disable_nmi_nosync - disable an nmi without waiting
769 * @irq: Interrupt to disable
771 * Disable the selected interrupt line. Disables and enables are
773 * The interrupt to disable must have been requested through request_nmi.
774 * Unlike disable_nmi(), this function does not ensure existing
775 * instances of the IRQ handler have completed before returning.
777 void disable_nmi_nosync(unsigned int irq)
779 disable_irq_nosync(irq);
782 void __enable_irq(struct irq_desc *desc)
784 switch (desc->depth) {
787 WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n",
788 irq_desc_get_irq(desc));
791 if (desc->istate & IRQS_SUSPENDED)
793 /* Prevent probing on this irq: */
794 irq_settings_set_noprobe(desc);
796 * Call irq_startup() not irq_enable() here because the
797 * interrupt might be marked NOAUTOEN. So irq_startup()
798 * needs to be invoked when it gets enabled the first
799 * time. If it was already started up, then irq_startup()
800 * will invoke irq_enable() under the hood.
802 irq_startup(desc, IRQ_RESEND, IRQ_START_FORCE);
811 * enable_irq - enable handling of an irq
812 * @irq: Interrupt to enable
814 * Undoes the effect of one call to disable_irq(). If this
815 * matches the last disable, processing of interrupts on this
816 * IRQ line is re-enabled.
818 * This function may be called from IRQ context only when
819 * desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
821 void enable_irq(unsigned int irq)
824 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
828 if (WARN(!desc->irq_data.chip,
829 KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
834 irq_put_desc_busunlock(desc, flags);
836 EXPORT_SYMBOL(enable_irq);
839 * enable_nmi - enable handling of an nmi
840 * @irq: Interrupt to enable
842 * The interrupt to enable must have been requested through request_nmi.
843 * Undoes the effect of one call to disable_nmi(). If this
844 * matches the last disable, processing of interrupts on this
845 * IRQ line is re-enabled.
847 void enable_nmi(unsigned int irq)
852 static int set_irq_wake_real(unsigned int irq, unsigned int on)
854 struct irq_desc *desc = irq_to_desc(irq);
857 if (irq_desc_get_chip(desc)->flags & IRQCHIP_SKIP_SET_WAKE)
860 if (desc->irq_data.chip->irq_set_wake)
861 ret = desc->irq_data.chip->irq_set_wake(&desc->irq_data, on);
867 * irq_set_irq_wake - control irq power management wakeup
868 * @irq: interrupt to control
869 * @on: enable/disable power management wakeup
871 * Enable/disable power management wakeup mode, which is
872 * disabled by default. Enables and disables must match,
873 * just as they match for non-wakeup mode support.
875 * Wakeup mode lets this IRQ wake the system from sleep
876 * states like "suspend to RAM".
878 * Note: irq enable/disable state is completely orthogonal
879 * to the enable/disable state of irq wake. An irq can be
880 * disabled with disable_irq() and still wake the system as
881 * long as the irq has wake enabled. If this does not hold,
882 * then the underlying irq chip and the related driver need
883 * to be investigated.
885 int irq_set_irq_wake(unsigned int irq, unsigned int on)
888 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
894 /* Don't use NMIs as wake up interrupts please */
895 if (desc->istate & IRQS_NMI) {
900 /* wakeup-capable irqs can be shared between drivers that
901 * don't need to have the same sleep mode behaviors.
904 if (desc->wake_depth++ == 0) {
905 ret = set_irq_wake_real(irq, on);
907 desc->wake_depth = 0;
909 irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE);
912 if (desc->wake_depth == 0) {
913 WARN(1, "Unbalanced IRQ %d wake disable\n", irq);
914 } else if (--desc->wake_depth == 0) {
915 ret = set_irq_wake_real(irq, on);
917 desc->wake_depth = 1;
919 irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
924 irq_put_desc_busunlock(desc, flags);
927 EXPORT_SYMBOL(irq_set_irq_wake);
930 * Internal function that tells the architecture code whether a
931 * particular irq has been exclusively allocated or is available
934 int can_request_irq(unsigned int irq, unsigned long irqflags)
937 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
943 if (irq_settings_can_request(desc)) {
945 irqflags & desc->action->flags & IRQF_SHARED)
948 irq_put_desc_unlock(desc, flags);
952 int __irq_set_trigger(struct irq_desc *desc, unsigned long flags)
954 struct irq_chip *chip = desc->irq_data.chip;
957 if (!chip || !chip->irq_set_type) {
959 * IRQF_TRIGGER_* but the PIC does not support multiple
962 pr_debug("No set_type function for IRQ %d (%s)\n",
963 irq_desc_get_irq(desc),
964 chip ? (chip->name ? : "unknown") : "unknown");
968 if (chip->flags & IRQCHIP_SET_TYPE_MASKED) {
969 if (!irqd_irq_masked(&desc->irq_data))
971 if (!irqd_irq_disabled(&desc->irq_data))
975 /* Mask all flags except trigger mode */
976 flags &= IRQ_TYPE_SENSE_MASK;
977 ret = chip->irq_set_type(&desc->irq_data, flags);
980 case IRQ_SET_MASK_OK:
981 case IRQ_SET_MASK_OK_DONE:
982 irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK);
983 irqd_set(&desc->irq_data, flags);
986 case IRQ_SET_MASK_OK_NOCOPY:
987 flags = irqd_get_trigger_type(&desc->irq_data);
988 irq_settings_set_trigger_mask(desc, flags);
989 irqd_clear(&desc->irq_data, IRQD_LEVEL);
990 irq_settings_clr_level(desc);
991 if (flags & IRQ_TYPE_LEVEL_MASK) {
992 irq_settings_set_level(desc);
993 irqd_set(&desc->irq_data, IRQD_LEVEL);
999 pr_err("Setting trigger mode %lu for irq %u failed (%pS)\n",
1000 flags, irq_desc_get_irq(desc), chip->irq_set_type);
1007 #ifdef CONFIG_HARDIRQS_SW_RESEND
1008 int irq_set_parent(int irq, int parent_irq)
1010 unsigned long flags;
1011 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
1016 desc->parent_irq = parent_irq;
1018 irq_put_desc_unlock(desc, flags);
1021 EXPORT_SYMBOL_GPL(irq_set_parent);
1025 * Default primary interrupt handler for threaded interrupts. Is
1026 * assigned as primary handler when request_threaded_irq is called
1027 * with handler == NULL. Useful for oneshot interrupts.
1029 static irqreturn_t irq_default_primary_handler(int irq, void *dev_id)
1031 return IRQ_WAKE_THREAD;
1035 * Primary handler for nested threaded interrupts. Should never be
1038 static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)
1040 WARN(1, "Primary handler called for nested irq %d\n", irq);
1044 static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id)
1046 WARN(1, "Secondary action handler called for irq %d\n", irq);
1050 static int irq_wait_for_interrupt(struct irqaction *action)
1053 set_current_state(TASK_INTERRUPTIBLE);
1055 if (kthread_should_stop()) {
1056 /* may need to run one last time */
1057 if (test_and_clear_bit(IRQTF_RUNTHREAD,
1058 &action->thread_flags)) {
1059 __set_current_state(TASK_RUNNING);
1062 __set_current_state(TASK_RUNNING);
1066 if (test_and_clear_bit(IRQTF_RUNTHREAD,
1067 &action->thread_flags)) {
1068 __set_current_state(TASK_RUNNING);
1076 * Oneshot interrupts keep the irq line masked until the threaded
1077 * handler finished. unmask if the interrupt has not been disabled and
1080 static void irq_finalize_oneshot(struct irq_desc *desc,
1081 struct irqaction *action)
1083 if (!(desc->istate & IRQS_ONESHOT) ||
1084 action->handler == irq_forced_secondary_handler)
1087 chip_bus_lock(desc);
1088 raw_spin_lock_irq(&desc->lock);
1091 * Implausible though it may be we need to protect us against
1092 * the following scenario:
1094 * The thread is faster done than the hard interrupt handler
1095 * on the other CPU. If we unmask the irq line then the
1096 * interrupt can come in again and masks the line, leaves due
1097 * to IRQS_INPROGRESS and the irq line is masked forever.
1099 * This also serializes the state of shared oneshot handlers
1100 * versus "desc->threads_oneshot |= action->thread_mask;" in
1101 * irq_wake_thread(). See the comment there which explains the
1104 if (unlikely(irqd_irq_inprogress(&desc->irq_data))) {
1105 raw_spin_unlock_irq(&desc->lock);
1106 chip_bus_sync_unlock(desc);
1112 * Now check again, whether the thread should run. Otherwise
1113 * we would clear the threads_oneshot bit of this thread which
1116 if (test_bit(IRQTF_RUNTHREAD, &action->thread_flags))
1119 desc->threads_oneshot &= ~action->thread_mask;
1121 if (!desc->threads_oneshot && !irqd_irq_disabled(&desc->irq_data) &&
1122 irqd_irq_masked(&desc->irq_data))
1123 unmask_threaded_irq(desc);
1126 raw_spin_unlock_irq(&desc->lock);
1127 chip_bus_sync_unlock(desc);
1132 * Check whether we need to change the affinity of the interrupt thread.
1135 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
1140 if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags))
1144 * In case we are out of memory we set IRQTF_AFFINITY again and
1145 * try again next time
1147 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {
1148 set_bit(IRQTF_AFFINITY, &action->thread_flags);
1152 raw_spin_lock_irq(&desc->lock);
1154 * This code is triggered unconditionally. Check the affinity
1155 * mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
1157 if (cpumask_available(desc->irq_common_data.affinity)) {
1158 const struct cpumask *m;
1160 m = irq_data_get_effective_affinity_mask(&desc->irq_data);
1161 cpumask_copy(mask, m);
1165 raw_spin_unlock_irq(&desc->lock);
1168 set_cpus_allowed_ptr(current, mask);
1169 free_cpumask_var(mask);
1173 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { }
1177 * Interrupts which are not explicitly requested as threaded
1178 * interrupts rely on the implicit bh/preempt disable of the hard irq
1179 * context. So we need to disable bh here to avoid deadlocks and other
1183 irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
1188 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
1189 local_irq_disable();
1190 ret = action->thread_fn(action->irq, action->dev_id);
1191 if (ret == IRQ_HANDLED)
1192 atomic_inc(&desc->threads_handled);
1194 irq_finalize_oneshot(desc, action);
1195 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
1202 * Interrupts explicitly requested as threaded interrupts want to be
1203 * preemptible - many of them need to sleep and wait for slow busses to
1206 static irqreturn_t irq_thread_fn(struct irq_desc *desc,
1207 struct irqaction *action)
1211 ret = action->thread_fn(action->irq, action->dev_id);
1212 if (ret == IRQ_HANDLED)
1213 atomic_inc(&desc->threads_handled);
1215 irq_finalize_oneshot(desc, action);
1219 static void wake_threads_waitq(struct irq_desc *desc)
1221 if (atomic_dec_and_test(&desc->threads_active))
1222 wake_up(&desc->wait_for_threads);
1225 static void irq_thread_dtor(struct callback_head *unused)
1227 struct task_struct *tsk = current;
1228 struct irq_desc *desc;
1229 struct irqaction *action;
1231 if (WARN_ON_ONCE(!(current->flags & PF_EXITING)))
1234 action = kthread_data(tsk);
1236 pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
1237 tsk->comm, tsk->pid, action->irq);
1240 desc = irq_to_desc(action->irq);
1242 * If IRQTF_RUNTHREAD is set, we need to decrement
1243 * desc->threads_active and wake possible waiters.
1245 if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
1246 wake_threads_waitq(desc);
1248 /* Prevent a stale desc->threads_oneshot */
1249 irq_finalize_oneshot(desc, action);
1252 static void irq_wake_secondary(struct irq_desc *desc, struct irqaction *action)
1254 struct irqaction *secondary = action->secondary;
1256 if (WARN_ON_ONCE(!secondary))
1259 raw_spin_lock_irq(&desc->lock);
1260 __irq_wake_thread(desc, secondary);
1261 raw_spin_unlock_irq(&desc->lock);
1265 * Internal function to notify that a interrupt thread is ready.
1267 static void irq_thread_set_ready(struct irq_desc *desc,
1268 struct irqaction *action)
1270 set_bit(IRQTF_READY, &action->thread_flags);
1271 wake_up(&desc->wait_for_threads);
1275 * Internal function to wake up a interrupt thread and wait until it is
1278 static void wake_up_and_wait_for_irq_thread_ready(struct irq_desc *desc,
1279 struct irqaction *action)
1281 if (!action || !action->thread)
1284 wake_up_process(action->thread);
1285 wait_event(desc->wait_for_threads,
1286 test_bit(IRQTF_READY, &action->thread_flags));
1290 * Interrupt handler thread
1292 static int irq_thread(void *data)
1294 struct callback_head on_exit_work;
1295 struct irqaction *action = data;
1296 struct irq_desc *desc = irq_to_desc(action->irq);
1297 irqreturn_t (*handler_fn)(struct irq_desc *desc,
1298 struct irqaction *action);
1300 irq_thread_set_ready(desc, action);
1302 sched_set_fifo(current);
1304 if (force_irqthreads() && test_bit(IRQTF_FORCED_THREAD,
1305 &action->thread_flags))
1306 handler_fn = irq_forced_thread_fn;
1308 handler_fn = irq_thread_fn;
1310 init_task_work(&on_exit_work, irq_thread_dtor);
1311 task_work_add(current, &on_exit_work, TWA_NONE);
1313 irq_thread_check_affinity(desc, action);
1315 while (!irq_wait_for_interrupt(action)) {
1316 irqreturn_t action_ret;
1318 irq_thread_check_affinity(desc, action);
1320 action_ret = handler_fn(desc, action);
1321 if (action_ret == IRQ_WAKE_THREAD)
1322 irq_wake_secondary(desc, action);
1324 wake_threads_waitq(desc);
1328 * This is the regular exit path. __free_irq() is stopping the
1329 * thread via kthread_stop() after calling
1330 * synchronize_hardirq(). So neither IRQTF_RUNTHREAD nor the
1331 * oneshot mask bit can be set.
1333 task_work_cancel(current, irq_thread_dtor);
1338 * irq_wake_thread - wake the irq thread for the action identified by dev_id
1339 * @irq: Interrupt line
1340 * @dev_id: Device identity for which the thread should be woken
1343 void irq_wake_thread(unsigned int irq, void *dev_id)
1345 struct irq_desc *desc = irq_to_desc(irq);
1346 struct irqaction *action;
1347 unsigned long flags;
1349 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1352 raw_spin_lock_irqsave(&desc->lock, flags);
1353 for_each_action_of_desc(desc, action) {
1354 if (action->dev_id == dev_id) {
1356 __irq_wake_thread(desc, action);
1360 raw_spin_unlock_irqrestore(&desc->lock, flags);
1362 EXPORT_SYMBOL_GPL(irq_wake_thread);
1364 static int irq_setup_forced_threading(struct irqaction *new)
1366 if (!force_irqthreads())
1368 if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))
1372 * No further action required for interrupts which are requested as
1373 * threaded interrupts already
1375 if (new->handler == irq_default_primary_handler)
1378 new->flags |= IRQF_ONESHOT;
1381 * Handle the case where we have a real primary handler and a
1382 * thread handler. We force thread them as well by creating a
1385 if (new->handler && new->thread_fn) {
1386 /* Allocate the secondary action */
1387 new->secondary = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
1388 if (!new->secondary)
1390 new->secondary->handler = irq_forced_secondary_handler;
1391 new->secondary->thread_fn = new->thread_fn;
1392 new->secondary->dev_id = new->dev_id;
1393 new->secondary->irq = new->irq;
1394 new->secondary->name = new->name;
1396 /* Deal with the primary handler */
1397 set_bit(IRQTF_FORCED_THREAD, &new->thread_flags);
1398 new->thread_fn = new->handler;
1399 new->handler = irq_default_primary_handler;
1403 static int irq_request_resources(struct irq_desc *desc)
1405 struct irq_data *d = &desc->irq_data;
1406 struct irq_chip *c = d->chip;
1408 return c->irq_request_resources ? c->irq_request_resources(d) : 0;
1411 static void irq_release_resources(struct irq_desc *desc)
1413 struct irq_data *d = &desc->irq_data;
1414 struct irq_chip *c = d->chip;
1416 if (c->irq_release_resources)
1417 c->irq_release_resources(d);
1420 static bool irq_supports_nmi(struct irq_desc *desc)
1422 struct irq_data *d = irq_desc_get_irq_data(desc);
1424 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1425 /* Only IRQs directly managed by the root irqchip can be set as NMI */
1429 /* Don't support NMIs for chips behind a slow bus */
1430 if (d->chip->irq_bus_lock || d->chip->irq_bus_sync_unlock)
1433 return d->chip->flags & IRQCHIP_SUPPORTS_NMI;
1436 static int irq_nmi_setup(struct irq_desc *desc)
1438 struct irq_data *d = irq_desc_get_irq_data(desc);
1439 struct irq_chip *c = d->chip;
1441 return c->irq_nmi_setup ? c->irq_nmi_setup(d) : -EINVAL;
1444 static void irq_nmi_teardown(struct irq_desc *desc)
1446 struct irq_data *d = irq_desc_get_irq_data(desc);
1447 struct irq_chip *c = d->chip;
1449 if (c->irq_nmi_teardown)
1450 c->irq_nmi_teardown(d);
1454 setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
1456 struct task_struct *t;
1459 t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
1462 t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq,
1470 * We keep the reference to the task struct even if
1471 * the thread dies to avoid that the interrupt code
1472 * references an already freed task_struct.
1474 new->thread = get_task_struct(t);
1476 * Tell the thread to set its affinity. This is
1477 * important for shared interrupt handlers as we do
1478 * not invoke setup_affinity() for the secondary
1479 * handlers as everything is already set up. Even for
1480 * interrupts marked with IRQF_NO_BALANCE this is
1481 * correct as we want the thread to move to the cpu(s)
1482 * on which the requesting code placed the interrupt.
1484 set_bit(IRQTF_AFFINITY, &new->thread_flags);
1489 * Internal function to register an irqaction - typically used to
1490 * allocate special interrupts that are part of the architecture.
1494 * desc->request_mutex Provides serialization against a concurrent free_irq()
1495 * chip_bus_lock Provides serialization for slow bus operations
1496 * desc->lock Provides serialization against hard interrupts
1498 * chip_bus_lock and desc->lock are sufficient for all other management and
1499 * interrupt related functions. desc->request_mutex solely serializes
1500 * request/free_irq().
1503 __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
1505 struct irqaction *old, **old_ptr;
1506 unsigned long flags, thread_mask = 0;
1507 int ret, nested, shared = 0;
1512 if (desc->irq_data.chip == &no_irq_chip)
1514 if (!try_module_get(desc->owner))
1520 * If the trigger type is not specified by the caller,
1521 * then use the default for this interrupt.
1523 if (!(new->flags & IRQF_TRIGGER_MASK))
1524 new->flags |= irqd_get_trigger_type(&desc->irq_data);
1527 * Check whether the interrupt nests into another interrupt
1530 nested = irq_settings_is_nested_thread(desc);
1532 if (!new->thread_fn) {
1537 * Replace the primary handler which was provided from
1538 * the driver for non nested interrupt handling by the
1539 * dummy function which warns when called.
1541 new->handler = irq_nested_primary_handler;
1543 if (irq_settings_can_thread(desc)) {
1544 ret = irq_setup_forced_threading(new);
1551 * Create a handler thread when a thread function is supplied
1552 * and the interrupt does not nest into another interrupt
1555 if (new->thread_fn && !nested) {
1556 ret = setup_irq_thread(new, irq, false);
1559 if (new->secondary) {
1560 ret = setup_irq_thread(new->secondary, irq, true);
1567 * Drivers are often written to work w/o knowledge about the
1568 * underlying irq chip implementation, so a request for a
1569 * threaded irq without a primary hard irq context handler
1570 * requires the ONESHOT flag to be set. Some irq chips like
1571 * MSI based interrupts are per se one shot safe. Check the
1572 * chip flags, so we can avoid the unmask dance at the end of
1573 * the threaded handler for those.
1575 if (desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)
1576 new->flags &= ~IRQF_ONESHOT;
1579 * Protects against a concurrent __free_irq() call which might wait
1580 * for synchronize_hardirq() to complete without holding the optional
1581 * chip bus lock and desc->lock. Also protects against handing out
1582 * a recycled oneshot thread_mask bit while it's still in use by
1583 * its previous owner.
1585 mutex_lock(&desc->request_mutex);
1588 * Acquire bus lock as the irq_request_resources() callback below
1589 * might rely on the serialization or the magic power management
1590 * functions which are abusing the irq_bus_lock() callback,
1592 chip_bus_lock(desc);
1594 /* First installed action requests resources. */
1595 if (!desc->action) {
1596 ret = irq_request_resources(desc);
1598 pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
1599 new->name, irq, desc->irq_data.chip->name);
1600 goto out_bus_unlock;
1605 * The following block of code has to be executed atomically
1606 * protected against a concurrent interrupt and any of the other
1607 * management calls which are not serialized via
1608 * desc->request_mutex or the optional bus lock.
1610 raw_spin_lock_irqsave(&desc->lock, flags);
1611 old_ptr = &desc->action;
1615 * Can't share interrupts unless both agree to and are
1616 * the same type (level, edge, polarity). So both flag
1617 * fields must have IRQF_SHARED set and the bits which
1618 * set the trigger type must match. Also all must
1620 * Interrupt lines used for NMIs cannot be shared.
1622 unsigned int oldtype;
1624 if (desc->istate & IRQS_NMI) {
1625 pr_err("Invalid attempt to share NMI for %s (irq %d) on irqchip %s.\n",
1626 new->name, irq, desc->irq_data.chip->name);
1632 * If nobody did set the configuration before, inherit
1633 * the one provided by the requester.
1635 if (irqd_trigger_type_was_set(&desc->irq_data)) {
1636 oldtype = irqd_get_trigger_type(&desc->irq_data);
1638 oldtype = new->flags & IRQF_TRIGGER_MASK;
1639 irqd_set_trigger_type(&desc->irq_data, oldtype);
1642 if (!((old->flags & new->flags) & IRQF_SHARED) ||
1643 (oldtype != (new->flags & IRQF_TRIGGER_MASK)) ||
1644 ((old->flags ^ new->flags) & IRQF_ONESHOT))
1647 /* All handlers must agree on per-cpuness */
1648 if ((old->flags & IRQF_PERCPU) !=
1649 (new->flags & IRQF_PERCPU))
1652 /* add new interrupt at end of irq queue */
1655 * Or all existing action->thread_mask bits,
1656 * so we can find the next zero bit for this
1659 thread_mask |= old->thread_mask;
1660 old_ptr = &old->next;
1667 * Setup the thread mask for this irqaction for ONESHOT. For
1668 * !ONESHOT irqs the thread mask is 0 so we can avoid a
1669 * conditional in irq_wake_thread().
1671 if (new->flags & IRQF_ONESHOT) {
1673 * Unlikely to have 32 resp 64 irqs sharing one line,
1676 if (thread_mask == ~0UL) {
1681 * The thread_mask for the action is or'ed to
1682 * desc->thread_active to indicate that the
1683 * IRQF_ONESHOT thread handler has been woken, but not
1684 * yet finished. The bit is cleared when a thread
1685 * completes. When all threads of a shared interrupt
1686 * line have completed desc->threads_active becomes
1687 * zero and the interrupt line is unmasked. See
1688 * handle.c:irq_wake_thread() for further information.
1690 * If no thread is woken by primary (hard irq context)
1691 * interrupt handlers, then desc->threads_active is
1692 * also checked for zero to unmask the irq line in the
1693 * affected hard irq flow handlers
1694 * (handle_[fasteoi|level]_irq).
1696 * The new action gets the first zero bit of
1697 * thread_mask assigned. See the loop above which or's
1698 * all existing action->thread_mask bits.
1700 new->thread_mask = 1UL << ffz(thread_mask);
1702 } else if (new->handler == irq_default_primary_handler &&
1703 !(desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)) {
1705 * The interrupt was requested with handler = NULL, so
1706 * we use the default primary handler for it. But it
1707 * does not have the oneshot flag set. In combination
1708 * with level interrupts this is deadly, because the
1709 * default primary handler just wakes the thread, then
1710 * the irq lines is reenabled, but the device still
1711 * has the level irq asserted. Rinse and repeat....
1713 * While this works for edge type interrupts, we play
1714 * it safe and reject unconditionally because we can't
1715 * say for sure which type this interrupt really
1716 * has. The type flags are unreliable as the
1717 * underlying chip implementation can override them.
1719 pr_err("Threaded irq requested with handler=NULL and !ONESHOT for %s (irq %d)\n",
1726 /* Setup the type (level, edge polarity) if configured: */
1727 if (new->flags & IRQF_TRIGGER_MASK) {
1728 ret = __irq_set_trigger(desc,
1729 new->flags & IRQF_TRIGGER_MASK);
1736 * Activate the interrupt. That activation must happen
1737 * independently of IRQ_NOAUTOEN. request_irq() can fail
1738 * and the callers are supposed to handle
1739 * that. enable_irq() of an interrupt requested with
1740 * IRQ_NOAUTOEN is not supposed to fail. The activation
1741 * keeps it in shutdown mode, it merily associates
1742 * resources if necessary and if that's not possible it
1743 * fails. Interrupts which are in managed shutdown mode
1744 * will simply ignore that activation request.
1746 ret = irq_activate(desc);
1750 desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \
1751 IRQS_ONESHOT | IRQS_WAITING);
1752 irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
1754 if (new->flags & IRQF_PERCPU) {
1755 irqd_set(&desc->irq_data, IRQD_PER_CPU);
1756 irq_settings_set_per_cpu(desc);
1757 if (new->flags & IRQF_NO_DEBUG)
1758 irq_settings_set_no_debug(desc);
1762 irq_settings_set_no_debug(desc);
1764 if (new->flags & IRQF_ONESHOT)
1765 desc->istate |= IRQS_ONESHOT;
1767 /* Exclude IRQ from balancing if requested */
1768 if (new->flags & IRQF_NOBALANCING) {
1769 irq_settings_set_no_balancing(desc);
1770 irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
1773 if (!(new->flags & IRQF_NO_AUTOEN) &&
1774 irq_settings_can_autoenable(desc)) {
1775 irq_startup(desc, IRQ_RESEND, IRQ_START_COND);
1778 * Shared interrupts do not go well with disabling
1779 * auto enable. The sharing interrupt might request
1780 * it while it's still disabled and then wait for
1781 * interrupts forever.
1783 WARN_ON_ONCE(new->flags & IRQF_SHARED);
1784 /* Undo nested disables: */
1788 } else if (new->flags & IRQF_TRIGGER_MASK) {
1789 unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK;
1790 unsigned int omsk = irqd_get_trigger_type(&desc->irq_data);
1793 /* hope the handler works with current trigger mode */
1794 pr_warn("irq %d uses trigger mode %u; requested %u\n",
1800 irq_pm_install_action(desc, new);
1802 /* Reset broken irq detection when installing new handler */
1803 desc->irq_count = 0;
1804 desc->irqs_unhandled = 0;
1807 * Check whether we disabled the irq via the spurious handler
1808 * before. Reenable it and give it another chance.
1810 if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) {
1811 desc->istate &= ~IRQS_SPURIOUS_DISABLED;
1815 raw_spin_unlock_irqrestore(&desc->lock, flags);
1816 chip_bus_sync_unlock(desc);
1817 mutex_unlock(&desc->request_mutex);
1819 irq_setup_timings(desc, new);
1821 wake_up_and_wait_for_irq_thread_ready(desc, new);
1822 wake_up_and_wait_for_irq_thread_ready(desc, new->secondary);
1824 register_irq_proc(irq, desc);
1826 register_handler_proc(irq, new);
1830 if (!(new->flags & IRQF_PROBE_SHARED)) {
1831 pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
1832 irq, new->flags, new->name, old->flags, old->name);
1833 #ifdef CONFIG_DEBUG_SHIRQ
1840 raw_spin_unlock_irqrestore(&desc->lock, flags);
1843 irq_release_resources(desc);
1845 chip_bus_sync_unlock(desc);
1846 mutex_unlock(&desc->request_mutex);
1850 struct task_struct *t = new->thread;
1856 if (new->secondary && new->secondary->thread) {
1857 struct task_struct *t = new->secondary->thread;
1859 new->secondary->thread = NULL;
1864 module_put(desc->owner);
1869 * Internal function to unregister an irqaction - used to free
1870 * regular and special interrupts that are part of the architecture.
1872 static struct irqaction *__free_irq(struct irq_desc *desc, void *dev_id)
1874 unsigned irq = desc->irq_data.irq;
1875 struct irqaction *action, **action_ptr;
1876 unsigned long flags;
1878 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
1880 mutex_lock(&desc->request_mutex);
1881 chip_bus_lock(desc);
1882 raw_spin_lock_irqsave(&desc->lock, flags);
1885 * There can be multiple actions per IRQ descriptor, find the right
1886 * one based on the dev_id:
1888 action_ptr = &desc->action;
1890 action = *action_ptr;
1893 WARN(1, "Trying to free already-free IRQ %d\n", irq);
1894 raw_spin_unlock_irqrestore(&desc->lock, flags);
1895 chip_bus_sync_unlock(desc);
1896 mutex_unlock(&desc->request_mutex);
1900 if (action->dev_id == dev_id)
1902 action_ptr = &action->next;
1905 /* Found it - now remove it from the list of entries: */
1906 *action_ptr = action->next;
1908 irq_pm_remove_action(desc, action);
1910 /* If this was the last handler, shut down the IRQ line: */
1911 if (!desc->action) {
1912 irq_settings_clr_disable_unlazy(desc);
1913 /* Only shutdown. Deactivate after synchronize_hardirq() */
1918 /* make sure affinity_hint is cleaned up */
1919 if (WARN_ON_ONCE(desc->affinity_hint))
1920 desc->affinity_hint = NULL;
1923 raw_spin_unlock_irqrestore(&desc->lock, flags);
1925 * Drop bus_lock here so the changes which were done in the chip
1926 * callbacks above are synced out to the irq chips which hang
1927 * behind a slow bus (I2C, SPI) before calling synchronize_hardirq().
1929 * Aside of that the bus_lock can also be taken from the threaded
1930 * handler in irq_finalize_oneshot() which results in a deadlock
1931 * because kthread_stop() would wait forever for the thread to
1932 * complete, which is blocked on the bus lock.
1934 * The still held desc->request_mutex() protects against a
1935 * concurrent request_irq() of this irq so the release of resources
1936 * and timing data is properly serialized.
1938 chip_bus_sync_unlock(desc);
1940 unregister_handler_proc(irq, action);
1943 * Make sure it's not being used on another CPU and if the chip
1944 * supports it also make sure that there is no (not yet serviced)
1945 * interrupt in flight at the hardware level.
1947 __synchronize_hardirq(desc, true);
1949 #ifdef CONFIG_DEBUG_SHIRQ
1951 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
1952 * event to happen even now it's being freed, so let's make sure that
1953 * is so by doing an extra call to the handler ....
1955 * ( We do this after actually deregistering it, to make sure that a
1956 * 'real' IRQ doesn't run in parallel with our fake. )
1958 if (action->flags & IRQF_SHARED) {
1959 local_irq_save(flags);
1960 action->handler(irq, dev_id);
1961 local_irq_restore(flags);
1966 * The action has already been removed above, but the thread writes
1967 * its oneshot mask bit when it completes. Though request_mutex is
1968 * held across this which prevents __setup_irq() from handing out
1969 * the same bit to a newly requested action.
1971 if (action->thread) {
1972 kthread_stop(action->thread);
1973 put_task_struct(action->thread);
1974 if (action->secondary && action->secondary->thread) {
1975 kthread_stop(action->secondary->thread);
1976 put_task_struct(action->secondary->thread);
1980 /* Last action releases resources */
1981 if (!desc->action) {
1983 * Reacquire bus lock as irq_release_resources() might
1984 * require it to deallocate resources over the slow bus.
1986 chip_bus_lock(desc);
1988 * There is no interrupt on the fly anymore. Deactivate it
1991 raw_spin_lock_irqsave(&desc->lock, flags);
1992 irq_domain_deactivate_irq(&desc->irq_data);
1993 raw_spin_unlock_irqrestore(&desc->lock, flags);
1995 irq_release_resources(desc);
1996 chip_bus_sync_unlock(desc);
1997 irq_remove_timings(desc);
2000 mutex_unlock(&desc->request_mutex);
2002 irq_chip_pm_put(&desc->irq_data);
2003 module_put(desc->owner);
2004 kfree(action->secondary);
2009 * free_irq - free an interrupt allocated with request_irq
2010 * @irq: Interrupt line to free
2011 * @dev_id: Device identity to free
2013 * Remove an interrupt handler. The handler is removed and if the
2014 * interrupt line is no longer in use by any driver it is disabled.
2015 * On a shared IRQ the caller must ensure the interrupt is disabled
2016 * on the card it drives before calling this function. The function
2017 * does not return until any executing interrupts for this IRQ
2020 * This function must not be called from interrupt context.
2022 * Returns the devname argument passed to request_irq.
2024 const void *free_irq(unsigned int irq, void *dev_id)
2026 struct irq_desc *desc = irq_to_desc(irq);
2027 struct irqaction *action;
2028 const char *devname;
2030 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2034 if (WARN_ON(desc->affinity_notify))
2035 desc->affinity_notify = NULL;
2038 action = __free_irq(desc, dev_id);
2043 devname = action->name;
2047 EXPORT_SYMBOL(free_irq);
2049 /* This function must be called with desc->lock held */
2050 static const void *__cleanup_nmi(unsigned int irq, struct irq_desc *desc)
2052 const char *devname = NULL;
2054 desc->istate &= ~IRQS_NMI;
2056 if (!WARN_ON(desc->action == NULL)) {
2057 irq_pm_remove_action(desc, desc->action);
2058 devname = desc->action->name;
2059 unregister_handler_proc(irq, desc->action);
2061 kfree(desc->action);
2062 desc->action = NULL;
2065 irq_settings_clr_disable_unlazy(desc);
2066 irq_shutdown_and_deactivate(desc);
2068 irq_release_resources(desc);
2070 irq_chip_pm_put(&desc->irq_data);
2071 module_put(desc->owner);
2076 const void *free_nmi(unsigned int irq, void *dev_id)
2078 struct irq_desc *desc = irq_to_desc(irq);
2079 unsigned long flags;
2080 const void *devname;
2082 if (!desc || WARN_ON(!(desc->istate & IRQS_NMI)))
2085 if (WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2088 /* NMI still enabled */
2089 if (WARN_ON(desc->depth == 0))
2090 disable_nmi_nosync(irq);
2092 raw_spin_lock_irqsave(&desc->lock, flags);
2094 irq_nmi_teardown(desc);
2095 devname = __cleanup_nmi(irq, desc);
2097 raw_spin_unlock_irqrestore(&desc->lock, flags);
2103 * request_threaded_irq - allocate an interrupt line
2104 * @irq: Interrupt line to allocate
2105 * @handler: Function to be called when the IRQ occurs.
2106 * Primary handler for threaded interrupts.
2107 * If handler is NULL and thread_fn != NULL
2108 * the default primary handler is installed.
2109 * @thread_fn: Function called from the irq handler thread
2110 * If NULL, no irq thread is created
2111 * @irqflags: Interrupt type flags
2112 * @devname: An ascii name for the claiming device
2113 * @dev_id: A cookie passed back to the handler function
2115 * This call allocates interrupt resources and enables the
2116 * interrupt line and IRQ handling. From the point this
2117 * call is made your handler function may be invoked. Since
2118 * your handler function must clear any interrupt the board
2119 * raises, you must take care both to initialise your hardware
2120 * and to set up the interrupt handler in the right order.
2122 * If you want to set up a threaded irq handler for your device
2123 * then you need to supply @handler and @thread_fn. @handler is
2124 * still called in hard interrupt context and has to check
2125 * whether the interrupt originates from the device. If yes it
2126 * needs to disable the interrupt on the device and return
2127 * IRQ_WAKE_THREAD which will wake up the handler thread and run
2128 * @thread_fn. This split handler design is necessary to support
2129 * shared interrupts.
2131 * Dev_id must be globally unique. Normally the address of the
2132 * device data structure is used as the cookie. Since the handler
2133 * receives this value it makes sense to use it.
2135 * If your interrupt is shared you must pass a non NULL dev_id
2136 * as this is required when freeing the interrupt.
2140 * IRQF_SHARED Interrupt is shared
2141 * IRQF_TRIGGER_* Specify active edge(s) or level
2142 * IRQF_ONESHOT Run thread_fn with interrupt line masked
2144 int request_threaded_irq(unsigned int irq, irq_handler_t handler,
2145 irq_handler_t thread_fn, unsigned long irqflags,
2146 const char *devname, void *dev_id)
2148 struct irqaction *action;
2149 struct irq_desc *desc;
2152 if (irq == IRQ_NOTCONNECTED)
2156 * Sanity-check: shared interrupts must pass in a real dev-ID,
2157 * otherwise we'll have trouble later trying to figure out
2158 * which interrupt is which (messes up the interrupt freeing
2161 * Also shared interrupts do not go well with disabling auto enable.
2162 * The sharing interrupt might request it while it's still disabled
2163 * and then wait for interrupts forever.
2165 * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
2166 * it cannot be set along with IRQF_NO_SUSPEND.
2168 if (((irqflags & IRQF_SHARED) && !dev_id) ||
2169 ((irqflags & IRQF_SHARED) && (irqflags & IRQF_NO_AUTOEN)) ||
2170 (!(irqflags & IRQF_SHARED) && (irqflags & IRQF_COND_SUSPEND)) ||
2171 ((irqflags & IRQF_NO_SUSPEND) && (irqflags & IRQF_COND_SUSPEND)))
2174 desc = irq_to_desc(irq);
2178 if (!irq_settings_can_request(desc) ||
2179 WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2185 handler = irq_default_primary_handler;
2188 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2192 action->handler = handler;
2193 action->thread_fn = thread_fn;
2194 action->flags = irqflags;
2195 action->name = devname;
2196 action->dev_id = dev_id;
2198 retval = irq_chip_pm_get(&desc->irq_data);
2204 retval = __setup_irq(irq, desc, action);
2207 irq_chip_pm_put(&desc->irq_data);
2208 kfree(action->secondary);
2212 #ifdef CONFIG_DEBUG_SHIRQ_FIXME
2213 if (!retval && (irqflags & IRQF_SHARED)) {
2215 * It's a shared IRQ -- the driver ought to be prepared for it
2216 * to happen immediately, so let's make sure....
2217 * We disable the irq to make sure that a 'real' IRQ doesn't
2218 * run in parallel with our fake.
2220 unsigned long flags;
2223 local_irq_save(flags);
2225 handler(irq, dev_id);
2227 local_irq_restore(flags);
2233 EXPORT_SYMBOL(request_threaded_irq);
2236 * request_any_context_irq - allocate an interrupt line
2237 * @irq: Interrupt line to allocate
2238 * @handler: Function to be called when the IRQ occurs.
2239 * Threaded handler for threaded interrupts.
2240 * @flags: Interrupt type flags
2241 * @name: An ascii name for the claiming device
2242 * @dev_id: A cookie passed back to the handler function
2244 * This call allocates interrupt resources and enables the
2245 * interrupt line and IRQ handling. It selects either a
2246 * hardirq or threaded handling method depending on the
2249 * On failure, it returns a negative value. On success,
2250 * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
2252 int request_any_context_irq(unsigned int irq, irq_handler_t handler,
2253 unsigned long flags, const char *name, void *dev_id)
2255 struct irq_desc *desc;
2258 if (irq == IRQ_NOTCONNECTED)
2261 desc = irq_to_desc(irq);
2265 if (irq_settings_is_nested_thread(desc)) {
2266 ret = request_threaded_irq(irq, NULL, handler,
2267 flags, name, dev_id);
2268 return !ret ? IRQC_IS_NESTED : ret;
2271 ret = request_irq(irq, handler, flags, name, dev_id);
2272 return !ret ? IRQC_IS_HARDIRQ : ret;
2274 EXPORT_SYMBOL_GPL(request_any_context_irq);
2277 * request_nmi - allocate an interrupt line for NMI delivery
2278 * @irq: Interrupt line to allocate
2279 * @handler: Function to be called when the IRQ occurs.
2280 * Threaded handler for threaded interrupts.
2281 * @irqflags: Interrupt type flags
2282 * @name: An ascii name for the claiming device
2283 * @dev_id: A cookie passed back to the handler function
2285 * This call allocates interrupt resources and enables the
2286 * interrupt line and IRQ handling. It sets up the IRQ line
2287 * to be handled as an NMI.
2289 * An interrupt line delivering NMIs cannot be shared and IRQ handling
2290 * cannot be threaded.
2292 * Interrupt lines requested for NMI delivering must produce per cpu
2293 * interrupts and have auto enabling setting disabled.
2295 * Dev_id must be globally unique. Normally the address of the
2296 * device data structure is used as the cookie. Since the handler
2297 * receives this value it makes sense to use it.
2299 * If the interrupt line cannot be used to deliver NMIs, function
2300 * will fail and return a negative value.
2302 int request_nmi(unsigned int irq, irq_handler_t handler,
2303 unsigned long irqflags, const char *name, void *dev_id)
2305 struct irqaction *action;
2306 struct irq_desc *desc;
2307 unsigned long flags;
2310 if (irq == IRQ_NOTCONNECTED)
2313 /* NMI cannot be shared, used for Polling */
2314 if (irqflags & (IRQF_SHARED | IRQF_COND_SUSPEND | IRQF_IRQPOLL))
2317 if (!(irqflags & IRQF_PERCPU))
2323 desc = irq_to_desc(irq);
2325 if (!desc || (irq_settings_can_autoenable(desc) &&
2326 !(irqflags & IRQF_NO_AUTOEN)) ||
2327 !irq_settings_can_request(desc) ||
2328 WARN_ON(irq_settings_is_per_cpu_devid(desc)) ||
2329 !irq_supports_nmi(desc))
2332 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2336 action->handler = handler;
2337 action->flags = irqflags | IRQF_NO_THREAD | IRQF_NOBALANCING;
2338 action->name = name;
2339 action->dev_id = dev_id;
2341 retval = irq_chip_pm_get(&desc->irq_data);
2345 retval = __setup_irq(irq, desc, action);
2349 raw_spin_lock_irqsave(&desc->lock, flags);
2351 /* Setup NMI state */
2352 desc->istate |= IRQS_NMI;
2353 retval = irq_nmi_setup(desc);
2355 __cleanup_nmi(irq, desc);
2356 raw_spin_unlock_irqrestore(&desc->lock, flags);
2360 raw_spin_unlock_irqrestore(&desc->lock, flags);
2365 irq_chip_pm_put(&desc->irq_data);
2372 void enable_percpu_irq(unsigned int irq, unsigned int type)
2374 unsigned int cpu = smp_processor_id();
2375 unsigned long flags;
2376 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2382 * If the trigger type is not specified by the caller, then
2383 * use the default for this interrupt.
2385 type &= IRQ_TYPE_SENSE_MASK;
2386 if (type == IRQ_TYPE_NONE)
2387 type = irqd_get_trigger_type(&desc->irq_data);
2389 if (type != IRQ_TYPE_NONE) {
2392 ret = __irq_set_trigger(desc, type);
2395 WARN(1, "failed to set type for IRQ%d\n", irq);
2400 irq_percpu_enable(desc, cpu);
2402 irq_put_desc_unlock(desc, flags);
2404 EXPORT_SYMBOL_GPL(enable_percpu_irq);
2406 void enable_percpu_nmi(unsigned int irq, unsigned int type)
2408 enable_percpu_irq(irq, type);
2412 * irq_percpu_is_enabled - Check whether the per cpu irq is enabled
2413 * @irq: Linux irq number to check for
2415 * Must be called from a non migratable context. Returns the enable
2416 * state of a per cpu interrupt on the current cpu.
2418 bool irq_percpu_is_enabled(unsigned int irq)
2420 unsigned int cpu = smp_processor_id();
2421 struct irq_desc *desc;
2422 unsigned long flags;
2425 desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2429 is_enabled = cpumask_test_cpu(cpu, desc->percpu_enabled);
2430 irq_put_desc_unlock(desc, flags);
2434 EXPORT_SYMBOL_GPL(irq_percpu_is_enabled);
2436 void disable_percpu_irq(unsigned int irq)
2438 unsigned int cpu = smp_processor_id();
2439 unsigned long flags;
2440 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2445 irq_percpu_disable(desc, cpu);
2446 irq_put_desc_unlock(desc, flags);
2448 EXPORT_SYMBOL_GPL(disable_percpu_irq);
2450 void disable_percpu_nmi(unsigned int irq)
2452 disable_percpu_irq(irq);
2456 * Internal function to unregister a percpu irqaction.
2458 static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_id)
2460 struct irq_desc *desc = irq_to_desc(irq);
2461 struct irqaction *action;
2462 unsigned long flags;
2464 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
2469 raw_spin_lock_irqsave(&desc->lock, flags);
2471 action = desc->action;
2472 if (!action || action->percpu_dev_id != dev_id) {
2473 WARN(1, "Trying to free already-free IRQ %d\n", irq);
2477 if (!cpumask_empty(desc->percpu_enabled)) {
2478 WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
2479 irq, cpumask_first(desc->percpu_enabled));
2483 /* Found it - now remove it from the list of entries: */
2484 desc->action = NULL;
2486 desc->istate &= ~IRQS_NMI;
2488 raw_spin_unlock_irqrestore(&desc->lock, flags);
2490 unregister_handler_proc(irq, action);
2492 irq_chip_pm_put(&desc->irq_data);
2493 module_put(desc->owner);
2497 raw_spin_unlock_irqrestore(&desc->lock, flags);
2502 * remove_percpu_irq - free a per-cpu interrupt
2503 * @irq: Interrupt line to free
2504 * @act: irqaction for the interrupt
2506 * Used to remove interrupts statically setup by the early boot process.
2508 void remove_percpu_irq(unsigned int irq, struct irqaction *act)
2510 struct irq_desc *desc = irq_to_desc(irq);
2512 if (desc && irq_settings_is_per_cpu_devid(desc))
2513 __free_percpu_irq(irq, act->percpu_dev_id);
2517 * free_percpu_irq - free an interrupt allocated with request_percpu_irq
2518 * @irq: Interrupt line to free
2519 * @dev_id: Device identity to free
2521 * Remove a percpu interrupt handler. The handler is removed, but
2522 * the interrupt line is not disabled. This must be done on each
2523 * CPU before calling this function. The function does not return
2524 * until any executing interrupts for this IRQ have completed.
2526 * This function must not be called from interrupt context.
2528 void free_percpu_irq(unsigned int irq, void __percpu *dev_id)
2530 struct irq_desc *desc = irq_to_desc(irq);
2532 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2535 chip_bus_lock(desc);
2536 kfree(__free_percpu_irq(irq, dev_id));
2537 chip_bus_sync_unlock(desc);
2539 EXPORT_SYMBOL_GPL(free_percpu_irq);
2541 void free_percpu_nmi(unsigned int irq, void __percpu *dev_id)
2543 struct irq_desc *desc = irq_to_desc(irq);
2545 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2548 if (WARN_ON(!(desc->istate & IRQS_NMI)))
2551 kfree(__free_percpu_irq(irq, dev_id));
2555 * setup_percpu_irq - setup a per-cpu interrupt
2556 * @irq: Interrupt line to setup
2557 * @act: irqaction for the interrupt
2559 * Used to statically setup per-cpu interrupts in the early boot process.
2561 int setup_percpu_irq(unsigned int irq, struct irqaction *act)
2563 struct irq_desc *desc = irq_to_desc(irq);
2566 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2569 retval = irq_chip_pm_get(&desc->irq_data);
2573 retval = __setup_irq(irq, desc, act);
2576 irq_chip_pm_put(&desc->irq_data);
2582 * __request_percpu_irq - allocate a percpu interrupt line
2583 * @irq: Interrupt line to allocate
2584 * @handler: Function to be called when the IRQ occurs.
2585 * @flags: Interrupt type flags (IRQF_TIMER only)
2586 * @devname: An ascii name for the claiming device
2587 * @dev_id: A percpu cookie passed back to the handler function
2589 * This call allocates interrupt resources and enables the
2590 * interrupt on the local CPU. If the interrupt is supposed to be
2591 * enabled on other CPUs, it has to be done on each CPU using
2592 * enable_percpu_irq().
2594 * Dev_id must be globally unique. It is a per-cpu variable, and
2595 * the handler gets called with the interrupted CPU's instance of
2598 int __request_percpu_irq(unsigned int irq, irq_handler_t handler,
2599 unsigned long flags, const char *devname,
2600 void __percpu *dev_id)
2602 struct irqaction *action;
2603 struct irq_desc *desc;
2609 desc = irq_to_desc(irq);
2610 if (!desc || !irq_settings_can_request(desc) ||
2611 !irq_settings_is_per_cpu_devid(desc))
2614 if (flags && flags != IRQF_TIMER)
2617 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2621 action->handler = handler;
2622 action->flags = flags | IRQF_PERCPU | IRQF_NO_SUSPEND;
2623 action->name = devname;
2624 action->percpu_dev_id = dev_id;
2626 retval = irq_chip_pm_get(&desc->irq_data);
2632 retval = __setup_irq(irq, desc, action);
2635 irq_chip_pm_put(&desc->irq_data);
2641 EXPORT_SYMBOL_GPL(__request_percpu_irq);
2644 * request_percpu_nmi - allocate a percpu interrupt line for NMI delivery
2645 * @irq: Interrupt line to allocate
2646 * @handler: Function to be called when the IRQ occurs.
2647 * @name: An ascii name for the claiming device
2648 * @dev_id: A percpu cookie passed back to the handler function
2650 * This call allocates interrupt resources for a per CPU NMI. Per CPU NMIs
2651 * have to be setup on each CPU by calling prepare_percpu_nmi() before
2652 * being enabled on the same CPU by using enable_percpu_nmi().
2654 * Dev_id must be globally unique. It is a per-cpu variable, and
2655 * the handler gets called with the interrupted CPU's instance of
2658 * Interrupt lines requested for NMI delivering should have auto enabling
2661 * If the interrupt line cannot be used to deliver NMIs, function
2662 * will fail returning a negative value.
2664 int request_percpu_nmi(unsigned int irq, irq_handler_t handler,
2665 const char *name, void __percpu *dev_id)
2667 struct irqaction *action;
2668 struct irq_desc *desc;
2669 unsigned long flags;
2675 desc = irq_to_desc(irq);
2677 if (!desc || !irq_settings_can_request(desc) ||
2678 !irq_settings_is_per_cpu_devid(desc) ||
2679 irq_settings_can_autoenable(desc) ||
2680 !irq_supports_nmi(desc))
2683 /* The line cannot already be NMI */
2684 if (desc->istate & IRQS_NMI)
2687 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2691 action->handler = handler;
2692 action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND | IRQF_NO_THREAD
2694 action->name = name;
2695 action->percpu_dev_id = dev_id;
2697 retval = irq_chip_pm_get(&desc->irq_data);
2701 retval = __setup_irq(irq, desc, action);
2705 raw_spin_lock_irqsave(&desc->lock, flags);
2706 desc->istate |= IRQS_NMI;
2707 raw_spin_unlock_irqrestore(&desc->lock, flags);
2712 irq_chip_pm_put(&desc->irq_data);
2720 * prepare_percpu_nmi - performs CPU local setup for NMI delivery
2721 * @irq: Interrupt line to prepare for NMI delivery
2723 * This call prepares an interrupt line to deliver NMI on the current CPU,
2724 * before that interrupt line gets enabled with enable_percpu_nmi().
2726 * As a CPU local operation, this should be called from non-preemptible
2729 * If the interrupt line cannot be used to deliver NMIs, function
2730 * will fail returning a negative value.
2732 int prepare_percpu_nmi(unsigned int irq)
2734 unsigned long flags;
2735 struct irq_desc *desc;
2738 WARN_ON(preemptible());
2740 desc = irq_get_desc_lock(irq, &flags,
2741 IRQ_GET_DESC_CHECK_PERCPU);
2745 if (WARN(!(desc->istate & IRQS_NMI),
2746 KERN_ERR "prepare_percpu_nmi called for a non-NMI interrupt: irq %u\n",
2752 ret = irq_nmi_setup(desc);
2754 pr_err("Failed to setup NMI delivery: irq %u\n", irq);
2759 irq_put_desc_unlock(desc, flags);
2764 * teardown_percpu_nmi - undoes NMI setup of IRQ line
2765 * @irq: Interrupt line from which CPU local NMI configuration should be
2768 * This call undoes the setup done by prepare_percpu_nmi().
2770 * IRQ line should not be enabled for the current CPU.
2772 * As a CPU local operation, this should be called from non-preemptible
2775 void teardown_percpu_nmi(unsigned int irq)
2777 unsigned long flags;
2778 struct irq_desc *desc;
2780 WARN_ON(preemptible());
2782 desc = irq_get_desc_lock(irq, &flags,
2783 IRQ_GET_DESC_CHECK_PERCPU);
2787 if (WARN_ON(!(desc->istate & IRQS_NMI)))
2790 irq_nmi_teardown(desc);
2792 irq_put_desc_unlock(desc, flags);
2795 int __irq_get_irqchip_state(struct irq_data *data, enum irqchip_irq_state which,
2798 struct irq_chip *chip;
2802 chip = irq_data_get_irq_chip(data);
2803 if (WARN_ON_ONCE(!chip))
2805 if (chip->irq_get_irqchip_state)
2807 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2808 data = data->parent_data;
2815 err = chip->irq_get_irqchip_state(data, which, state);
2820 * irq_get_irqchip_state - returns the irqchip state of a interrupt.
2821 * @irq: Interrupt line that is forwarded to a VM
2822 * @which: One of IRQCHIP_STATE_* the caller wants to know about
2823 * @state: a pointer to a boolean where the state is to be stored
2825 * This call snapshots the internal irqchip state of an
2826 * interrupt, returning into @state the bit corresponding to
2829 * This function should be called with preemption disabled if the
2830 * interrupt controller has per-cpu registers.
2832 int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2835 struct irq_desc *desc;
2836 struct irq_data *data;
2837 unsigned long flags;
2840 desc = irq_get_desc_buslock(irq, &flags, 0);
2844 data = irq_desc_get_irq_data(desc);
2846 err = __irq_get_irqchip_state(data, which, state);
2848 irq_put_desc_busunlock(desc, flags);
2851 EXPORT_SYMBOL_GPL(irq_get_irqchip_state);
2854 * irq_set_irqchip_state - set the state of a forwarded interrupt.
2855 * @irq: Interrupt line that is forwarded to a VM
2856 * @which: State to be restored (one of IRQCHIP_STATE_*)
2857 * @val: Value corresponding to @which
2859 * This call sets the internal irqchip state of an interrupt,
2860 * depending on the value of @which.
2862 * This function should be called with migration disabled if the
2863 * interrupt controller has per-cpu registers.
2865 int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2868 struct irq_desc *desc;
2869 struct irq_data *data;
2870 struct irq_chip *chip;
2871 unsigned long flags;
2874 desc = irq_get_desc_buslock(irq, &flags, 0);
2878 data = irq_desc_get_irq_data(desc);
2881 chip = irq_data_get_irq_chip(data);
2882 if (WARN_ON_ONCE(!chip)) {
2886 if (chip->irq_set_irqchip_state)
2888 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2889 data = data->parent_data;
2896 err = chip->irq_set_irqchip_state(data, which, val);
2899 irq_put_desc_busunlock(desc, flags);
2902 EXPORT_SYMBOL_GPL(irq_set_irqchip_state);
2905 * irq_has_action - Check whether an interrupt is requested
2906 * @irq: The linux irq number
2908 * Returns: A snapshot of the current state
2910 bool irq_has_action(unsigned int irq)
2915 res = irq_desc_has_action(irq_to_desc(irq));
2919 EXPORT_SYMBOL_GPL(irq_has_action);
2922 * irq_check_status_bit - Check whether bits in the irq descriptor status are set
2923 * @irq: The linux irq number
2924 * @bitmask: The bitmask to evaluate
2926 * Returns: True if one of the bits in @bitmask is set
2928 bool irq_check_status_bit(unsigned int irq, unsigned int bitmask)
2930 struct irq_desc *desc;
2934 desc = irq_to_desc(irq);
2936 res = !!(desc->status_use_accessors & bitmask);
2940 EXPORT_SYMBOL_GPL(irq_check_status_bit);