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);
197 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
198 static void irq_validate_effective_affinity(struct irq_data *data)
200 const struct cpumask *m = irq_data_get_effective_affinity_mask(data);
201 struct irq_chip *chip = irq_data_get_irq_chip(data);
203 if (!cpumask_empty(m))
205 pr_warn_once("irq_chip %s did not update eff. affinity mask of irq %u\n",
206 chip->name, data->irq);
209 static inline void irq_validate_effective_affinity(struct irq_data *data) { }
212 int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
215 struct irq_desc *desc = irq_data_to_desc(data);
216 struct irq_chip *chip = irq_data_get_irq_chip(data);
217 const struct cpumask *prog_mask;
220 static DEFINE_RAW_SPINLOCK(tmp_mask_lock);
221 static struct cpumask tmp_mask;
223 if (!chip || !chip->irq_set_affinity)
226 raw_spin_lock(&tmp_mask_lock);
228 * If this is a managed interrupt and housekeeping is enabled on
229 * it check whether the requested affinity mask intersects with
230 * a housekeeping CPU. If so, then remove the isolated CPUs from
231 * the mask and just keep the housekeeping CPU(s). This prevents
232 * the affinity setter from routing the interrupt to an isolated
233 * CPU to avoid that I/O submitted from a housekeeping CPU causes
234 * interrupts on an isolated one.
236 * If the masks do not intersect or include online CPU(s) then
237 * keep the requested mask. The isolated target CPUs are only
238 * receiving interrupts when the I/O operation was submitted
239 * directly from them.
241 * If all housekeeping CPUs in the affinity mask are offline, the
242 * interrupt will be migrated by the CPU hotplug code once a
243 * housekeeping CPU which belongs to the affinity mask comes
246 if (irqd_affinity_is_managed(data) &&
247 housekeeping_enabled(HK_TYPE_MANAGED_IRQ)) {
248 const struct cpumask *hk_mask;
250 hk_mask = housekeeping_cpumask(HK_TYPE_MANAGED_IRQ);
252 cpumask_and(&tmp_mask, mask, hk_mask);
253 if (!cpumask_intersects(&tmp_mask, cpu_online_mask))
256 prog_mask = &tmp_mask;
262 * Make sure we only provide online CPUs to the irqchip,
263 * unless we are being asked to force the affinity (in which
264 * case we do as we are told).
266 cpumask_and(&tmp_mask, prog_mask, cpu_online_mask);
267 if (!force && !cpumask_empty(&tmp_mask))
268 ret = chip->irq_set_affinity(data, &tmp_mask, force);
270 ret = chip->irq_set_affinity(data, mask, force);
274 raw_spin_unlock(&tmp_mask_lock);
277 case IRQ_SET_MASK_OK:
278 case IRQ_SET_MASK_OK_DONE:
279 cpumask_copy(desc->irq_common_data.affinity, mask);
281 case IRQ_SET_MASK_OK_NOCOPY:
282 irq_validate_effective_affinity(data);
283 irq_set_thread_affinity(desc);
290 #ifdef CONFIG_GENERIC_PENDING_IRQ
291 static inline int irq_set_affinity_pending(struct irq_data *data,
292 const struct cpumask *dest)
294 struct irq_desc *desc = irq_data_to_desc(data);
296 irqd_set_move_pending(data);
297 irq_copy_pending(desc, dest);
301 static inline int irq_set_affinity_pending(struct irq_data *data,
302 const struct cpumask *dest)
308 static int irq_try_set_affinity(struct irq_data *data,
309 const struct cpumask *dest, bool force)
311 int ret = irq_do_set_affinity(data, dest, force);
314 * In case that the underlying vector management is busy and the
315 * architecture supports the generic pending mechanism then utilize
316 * this to avoid returning an error to user space.
318 if (ret == -EBUSY && !force)
319 ret = irq_set_affinity_pending(data, dest);
323 static bool irq_set_affinity_deactivated(struct irq_data *data,
324 const struct cpumask *mask)
326 struct irq_desc *desc = irq_data_to_desc(data);
329 * Handle irq chips which can handle affinity only in activated
332 * If the interrupt is not yet activated, just store the affinity
333 * mask and do not call the chip driver at all. On activation the
334 * driver has to make sure anyway that the interrupt is in a
335 * usable state so startup works.
337 if (!IS_ENABLED(CONFIG_IRQ_DOMAIN_HIERARCHY) ||
338 irqd_is_activated(data) || !irqd_affinity_on_activate(data))
341 cpumask_copy(desc->irq_common_data.affinity, mask);
342 irq_data_update_effective_affinity(data, mask);
343 irqd_set(data, IRQD_AFFINITY_SET);
347 int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
350 struct irq_chip *chip = irq_data_get_irq_chip(data);
351 struct irq_desc *desc = irq_data_to_desc(data);
354 if (!chip || !chip->irq_set_affinity)
357 if (irq_set_affinity_deactivated(data, mask))
360 if (irq_can_move_pcntxt(data) && !irqd_is_setaffinity_pending(data)) {
361 ret = irq_try_set_affinity(data, mask, force);
363 irqd_set_move_pending(data);
364 irq_copy_pending(desc, mask);
367 if (desc->affinity_notify) {
368 kref_get(&desc->affinity_notify->kref);
369 if (!schedule_work(&desc->affinity_notify->work)) {
370 /* Work was already scheduled, drop our extra ref */
371 kref_put(&desc->affinity_notify->kref,
372 desc->affinity_notify->release);
375 irqd_set(data, IRQD_AFFINITY_SET);
381 * irq_update_affinity_desc - Update affinity management for an interrupt
382 * @irq: The interrupt number to update
383 * @affinity: Pointer to the affinity descriptor
385 * This interface can be used to configure the affinity management of
386 * interrupts which have been allocated already.
388 * There are certain limitations on when it may be used - attempts to use it
389 * for when the kernel is configured for generic IRQ reservation mode (in
390 * config GENERIC_IRQ_RESERVATION_MODE) will fail, as it may conflict with
391 * managed/non-managed interrupt accounting. In addition, attempts to use it on
392 * an interrupt which is already started or which has already been configured
393 * as managed will also fail, as these mean invalid init state or double init.
395 int irq_update_affinity_desc(unsigned int irq,
396 struct irq_affinity_desc *affinity)
398 struct irq_desc *desc;
404 * Supporting this with the reservation scheme used by x86 needs
405 * some more thought. Fail it for now.
407 if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE))
410 desc = irq_get_desc_buslock(irq, &flags, 0);
414 /* Requires the interrupt to be shut down */
415 if (irqd_is_started(&desc->irq_data)) {
420 /* Interrupts which are already managed cannot be modified */
421 if (irqd_affinity_is_managed(&desc->irq_data)) {
427 * Deactivate the interrupt. That's required to undo
428 * anything an earlier activation has established.
430 activated = irqd_is_activated(&desc->irq_data);
432 irq_domain_deactivate_irq(&desc->irq_data);
434 if (affinity->is_managed) {
435 irqd_set(&desc->irq_data, IRQD_AFFINITY_MANAGED);
436 irqd_set(&desc->irq_data, IRQD_MANAGED_SHUTDOWN);
439 cpumask_copy(desc->irq_common_data.affinity, &affinity->mask);
441 /* Restore the activation state */
443 irq_domain_activate_irq(&desc->irq_data, false);
446 irq_put_desc_busunlock(desc, flags);
450 static int __irq_set_affinity(unsigned int irq, const struct cpumask *mask,
453 struct irq_desc *desc = irq_to_desc(irq);
460 raw_spin_lock_irqsave(&desc->lock, flags);
461 ret = irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask, force);
462 raw_spin_unlock_irqrestore(&desc->lock, flags);
467 * irq_set_affinity - Set the irq affinity of a given irq
468 * @irq: Interrupt to set affinity
471 * Fails if cpumask does not contain an online CPU
473 int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
475 return __irq_set_affinity(irq, cpumask, false);
477 EXPORT_SYMBOL_GPL(irq_set_affinity);
480 * irq_force_affinity - Force the irq affinity of a given irq
481 * @irq: Interrupt to set affinity
484 * Same as irq_set_affinity, but without checking the mask against
487 * Solely for low level cpu hotplug code, where we need to make per
488 * cpu interrupts affine before the cpu becomes online.
490 int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
492 return __irq_set_affinity(irq, cpumask, true);
494 EXPORT_SYMBOL_GPL(irq_force_affinity);
496 int __irq_apply_affinity_hint(unsigned int irq, const struct cpumask *m,
500 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
504 desc->affinity_hint = m;
505 irq_put_desc_unlock(desc, flags);
506 if (m && setaffinity)
507 __irq_set_affinity(irq, m, false);
510 EXPORT_SYMBOL_GPL(__irq_apply_affinity_hint);
512 static void irq_affinity_notify(struct work_struct *work)
514 struct irq_affinity_notify *notify =
515 container_of(work, struct irq_affinity_notify, work);
516 struct irq_desc *desc = irq_to_desc(notify->irq);
517 cpumask_var_t cpumask;
520 if (!desc || !alloc_cpumask_var(&cpumask, GFP_KERNEL))
523 raw_spin_lock_irqsave(&desc->lock, flags);
524 if (irq_move_pending(&desc->irq_data))
525 irq_get_pending(cpumask, desc);
527 cpumask_copy(cpumask, desc->irq_common_data.affinity);
528 raw_spin_unlock_irqrestore(&desc->lock, flags);
530 notify->notify(notify, cpumask);
532 free_cpumask_var(cpumask);
534 kref_put(¬ify->kref, notify->release);
538 * irq_set_affinity_notifier - control notification of IRQ affinity changes
539 * @irq: Interrupt for which to enable/disable notification
540 * @notify: Context for notification, or %NULL to disable
541 * notification. Function pointers must be initialised;
542 * the other fields will be initialised by this function.
544 * Must be called in process context. Notification may only be enabled
545 * after the IRQ is allocated and must be disabled before the IRQ is
546 * freed using free_irq().
549 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
551 struct irq_desc *desc = irq_to_desc(irq);
552 struct irq_affinity_notify *old_notify;
555 /* The release function is promised process context */
558 if (!desc || desc->istate & IRQS_NMI)
561 /* Complete initialisation of *notify */
564 kref_init(¬ify->kref);
565 INIT_WORK(¬ify->work, irq_affinity_notify);
568 raw_spin_lock_irqsave(&desc->lock, flags);
569 old_notify = desc->affinity_notify;
570 desc->affinity_notify = notify;
571 raw_spin_unlock_irqrestore(&desc->lock, flags);
574 if (cancel_work_sync(&old_notify->work)) {
575 /* Pending work had a ref, put that one too */
576 kref_put(&old_notify->kref, old_notify->release);
578 kref_put(&old_notify->kref, old_notify->release);
583 EXPORT_SYMBOL_GPL(irq_set_affinity_notifier);
585 #ifndef CONFIG_AUTO_IRQ_AFFINITY
587 * Generic version of the affinity autoselector.
589 int irq_setup_affinity(struct irq_desc *desc)
591 struct cpumask *set = irq_default_affinity;
592 int ret, node = irq_desc_get_node(desc);
593 static DEFINE_RAW_SPINLOCK(mask_lock);
594 static struct cpumask mask;
596 /* Excludes PER_CPU and NO_BALANCE interrupts */
597 if (!__irq_can_set_affinity(desc))
600 raw_spin_lock(&mask_lock);
602 * Preserve the managed affinity setting and a userspace affinity
603 * setup, but make sure that one of the targets is online.
605 if (irqd_affinity_is_managed(&desc->irq_data) ||
606 irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) {
607 if (cpumask_intersects(desc->irq_common_data.affinity,
609 set = desc->irq_common_data.affinity;
611 irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET);
614 cpumask_and(&mask, cpu_online_mask, set);
615 if (cpumask_empty(&mask))
616 cpumask_copy(&mask, cpu_online_mask);
618 if (node != NUMA_NO_NODE) {
619 const struct cpumask *nodemask = cpumask_of_node(node);
621 /* make sure at least one of the cpus in nodemask is online */
622 if (cpumask_intersects(&mask, nodemask))
623 cpumask_and(&mask, &mask, nodemask);
625 ret = irq_do_set_affinity(&desc->irq_data, &mask, false);
626 raw_spin_unlock(&mask_lock);
630 /* Wrapper for ALPHA specific affinity selector magic */
631 int irq_setup_affinity(struct irq_desc *desc)
633 return irq_select_affinity(irq_desc_get_irq(desc));
635 #endif /* CONFIG_AUTO_IRQ_AFFINITY */
636 #endif /* CONFIG_SMP */
640 * irq_set_vcpu_affinity - Set vcpu affinity for the interrupt
641 * @irq: interrupt number to set affinity
642 * @vcpu_info: vCPU specific data or pointer to a percpu array of vCPU
643 * specific data for percpu_devid interrupts
645 * This function uses the vCPU specific data to set the vCPU
646 * affinity for an irq. The vCPU specific data is passed from
647 * outside, such as KVM. One example code path is as below:
648 * KVM -> IOMMU -> irq_set_vcpu_affinity().
650 int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info)
653 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
654 struct irq_data *data;
655 struct irq_chip *chip;
661 data = irq_desc_get_irq_data(desc);
663 chip = irq_data_get_irq_chip(data);
664 if (chip && chip->irq_set_vcpu_affinity)
666 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
667 data = data->parent_data;
674 ret = chip->irq_set_vcpu_affinity(data, vcpu_info);
675 irq_put_desc_unlock(desc, flags);
679 EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity);
681 void __disable_irq(struct irq_desc *desc)
687 static int __disable_irq_nosync(unsigned int irq)
690 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
695 irq_put_desc_busunlock(desc, flags);
700 * disable_irq_nosync - disable an irq without waiting
701 * @irq: Interrupt to disable
703 * Disable the selected interrupt line. Disables and Enables are
705 * Unlike disable_irq(), this function does not ensure existing
706 * instances of the IRQ handler have completed before returning.
708 * This function may be called from IRQ context.
710 void disable_irq_nosync(unsigned int irq)
712 __disable_irq_nosync(irq);
714 EXPORT_SYMBOL(disable_irq_nosync);
717 * disable_irq - disable an irq and wait for completion
718 * @irq: Interrupt to disable
720 * Disable the selected interrupt line. Enables and Disables are
722 * This function waits for any pending IRQ handlers for this interrupt
723 * to complete before returning. If you use this function while
724 * holding a resource the IRQ handler may need you will deadlock.
726 * Can only be called from preemptible code as it might sleep when
727 * an interrupt thread is associated to @irq.
730 void disable_irq(unsigned int irq)
733 if (!__disable_irq_nosync(irq))
734 synchronize_irq(irq);
736 EXPORT_SYMBOL(disable_irq);
739 * disable_hardirq - disables an irq and waits for hardirq completion
740 * @irq: Interrupt to disable
742 * Disable the selected interrupt line. Enables and Disables are
744 * This function waits for any pending hard IRQ handlers for this
745 * interrupt to complete before returning. If you use this function while
746 * holding a resource the hard IRQ handler may need you will deadlock.
748 * When used to optimistically disable an interrupt from atomic context
749 * the return value must be checked.
751 * Returns: false if a threaded handler is active.
753 * This function may be called - with care - from IRQ context.
755 bool disable_hardirq(unsigned int irq)
757 if (!__disable_irq_nosync(irq))
758 return synchronize_hardirq(irq);
762 EXPORT_SYMBOL_GPL(disable_hardirq);
765 * disable_nmi_nosync - disable an nmi without waiting
766 * @irq: Interrupt to disable
768 * Disable the selected interrupt line. Disables and enables are
770 * The interrupt to disable must have been requested through request_nmi.
771 * Unlike disable_nmi(), this function does not ensure existing
772 * instances of the IRQ handler have completed before returning.
774 void disable_nmi_nosync(unsigned int irq)
776 disable_irq_nosync(irq);
779 void __enable_irq(struct irq_desc *desc)
781 switch (desc->depth) {
784 WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n",
785 irq_desc_get_irq(desc));
788 if (desc->istate & IRQS_SUSPENDED)
790 /* Prevent probing on this irq: */
791 irq_settings_set_noprobe(desc);
793 * Call irq_startup() not irq_enable() here because the
794 * interrupt might be marked NOAUTOEN. So irq_startup()
795 * needs to be invoked when it gets enabled the first
796 * time. If it was already started up, then irq_startup()
797 * will invoke irq_enable() under the hood.
799 irq_startup(desc, IRQ_RESEND, IRQ_START_FORCE);
808 * enable_irq - enable handling of an irq
809 * @irq: Interrupt to enable
811 * Undoes the effect of one call to disable_irq(). If this
812 * matches the last disable, processing of interrupts on this
813 * IRQ line is re-enabled.
815 * This function may be called from IRQ context only when
816 * desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
818 void enable_irq(unsigned int irq)
821 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
825 if (WARN(!desc->irq_data.chip,
826 KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
831 irq_put_desc_busunlock(desc, flags);
833 EXPORT_SYMBOL(enable_irq);
836 * enable_nmi - enable handling of an nmi
837 * @irq: Interrupt to enable
839 * The interrupt to enable must have been requested through request_nmi.
840 * Undoes the effect of one call to disable_nmi(). If this
841 * matches the last disable, processing of interrupts on this
842 * IRQ line is re-enabled.
844 void enable_nmi(unsigned int irq)
849 static int set_irq_wake_real(unsigned int irq, unsigned int on)
851 struct irq_desc *desc = irq_to_desc(irq);
854 if (irq_desc_get_chip(desc)->flags & IRQCHIP_SKIP_SET_WAKE)
857 if (desc->irq_data.chip->irq_set_wake)
858 ret = desc->irq_data.chip->irq_set_wake(&desc->irq_data, on);
864 * irq_set_irq_wake - control irq power management wakeup
865 * @irq: interrupt to control
866 * @on: enable/disable power management wakeup
868 * Enable/disable power management wakeup mode, which is
869 * disabled by default. Enables and disables must match,
870 * just as they match for non-wakeup mode support.
872 * Wakeup mode lets this IRQ wake the system from sleep
873 * states like "suspend to RAM".
875 * Note: irq enable/disable state is completely orthogonal
876 * to the enable/disable state of irq wake. An irq can be
877 * disabled with disable_irq() and still wake the system as
878 * long as the irq has wake enabled. If this does not hold,
879 * then the underlying irq chip and the related driver need
880 * to be investigated.
882 int irq_set_irq_wake(unsigned int irq, unsigned int on)
885 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
891 /* Don't use NMIs as wake up interrupts please */
892 if (desc->istate & IRQS_NMI) {
897 /* wakeup-capable irqs can be shared between drivers that
898 * don't need to have the same sleep mode behaviors.
901 if (desc->wake_depth++ == 0) {
902 ret = set_irq_wake_real(irq, on);
904 desc->wake_depth = 0;
906 irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE);
909 if (desc->wake_depth == 0) {
910 WARN(1, "Unbalanced IRQ %d wake disable\n", irq);
911 } else if (--desc->wake_depth == 0) {
912 ret = set_irq_wake_real(irq, on);
914 desc->wake_depth = 1;
916 irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
921 irq_put_desc_busunlock(desc, flags);
924 EXPORT_SYMBOL(irq_set_irq_wake);
927 * Internal function that tells the architecture code whether a
928 * particular irq has been exclusively allocated or is available
931 int can_request_irq(unsigned int irq, unsigned long irqflags)
934 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
940 if (irq_settings_can_request(desc)) {
942 irqflags & desc->action->flags & IRQF_SHARED)
945 irq_put_desc_unlock(desc, flags);
949 int __irq_set_trigger(struct irq_desc *desc, unsigned long flags)
951 struct irq_chip *chip = desc->irq_data.chip;
954 if (!chip || !chip->irq_set_type) {
956 * IRQF_TRIGGER_* but the PIC does not support multiple
959 pr_debug("No set_type function for IRQ %d (%s)\n",
960 irq_desc_get_irq(desc),
961 chip ? (chip->name ? : "unknown") : "unknown");
965 if (chip->flags & IRQCHIP_SET_TYPE_MASKED) {
966 if (!irqd_irq_masked(&desc->irq_data))
968 if (!irqd_irq_disabled(&desc->irq_data))
972 /* Mask all flags except trigger mode */
973 flags &= IRQ_TYPE_SENSE_MASK;
974 ret = chip->irq_set_type(&desc->irq_data, flags);
977 case IRQ_SET_MASK_OK:
978 case IRQ_SET_MASK_OK_DONE:
979 irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK);
980 irqd_set(&desc->irq_data, flags);
983 case IRQ_SET_MASK_OK_NOCOPY:
984 flags = irqd_get_trigger_type(&desc->irq_data);
985 irq_settings_set_trigger_mask(desc, flags);
986 irqd_clear(&desc->irq_data, IRQD_LEVEL);
987 irq_settings_clr_level(desc);
988 if (flags & IRQ_TYPE_LEVEL_MASK) {
989 irq_settings_set_level(desc);
990 irqd_set(&desc->irq_data, IRQD_LEVEL);
996 pr_err("Setting trigger mode %lu for irq %u failed (%pS)\n",
997 flags, irq_desc_get_irq(desc), chip->irq_set_type);
1004 #ifdef CONFIG_HARDIRQS_SW_RESEND
1005 int irq_set_parent(int irq, int parent_irq)
1007 unsigned long flags;
1008 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
1013 desc->parent_irq = parent_irq;
1015 irq_put_desc_unlock(desc, flags);
1018 EXPORT_SYMBOL_GPL(irq_set_parent);
1022 * Default primary interrupt handler for threaded interrupts. Is
1023 * assigned as primary handler when request_threaded_irq is called
1024 * with handler == NULL. Useful for oneshot interrupts.
1026 static irqreturn_t irq_default_primary_handler(int irq, void *dev_id)
1028 return IRQ_WAKE_THREAD;
1032 * Primary handler for nested threaded interrupts. Should never be
1035 static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)
1037 WARN(1, "Primary handler called for nested irq %d\n", irq);
1041 static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id)
1043 WARN(1, "Secondary action handler called for irq %d\n", irq);
1047 static int irq_wait_for_interrupt(struct irqaction *action)
1050 set_current_state(TASK_INTERRUPTIBLE);
1052 if (kthread_should_stop()) {
1053 /* may need to run one last time */
1054 if (test_and_clear_bit(IRQTF_RUNTHREAD,
1055 &action->thread_flags)) {
1056 __set_current_state(TASK_RUNNING);
1059 __set_current_state(TASK_RUNNING);
1063 if (test_and_clear_bit(IRQTF_RUNTHREAD,
1064 &action->thread_flags)) {
1065 __set_current_state(TASK_RUNNING);
1073 * Oneshot interrupts keep the irq line masked until the threaded
1074 * handler finished. unmask if the interrupt has not been disabled and
1077 static void irq_finalize_oneshot(struct irq_desc *desc,
1078 struct irqaction *action)
1080 if (!(desc->istate & IRQS_ONESHOT) ||
1081 action->handler == irq_forced_secondary_handler)
1084 chip_bus_lock(desc);
1085 raw_spin_lock_irq(&desc->lock);
1088 * Implausible though it may be we need to protect us against
1089 * the following scenario:
1091 * The thread is faster done than the hard interrupt handler
1092 * on the other CPU. If we unmask the irq line then the
1093 * interrupt can come in again and masks the line, leaves due
1094 * to IRQS_INPROGRESS and the irq line is masked forever.
1096 * This also serializes the state of shared oneshot handlers
1097 * versus "desc->threads_oneshot |= action->thread_mask;" in
1098 * irq_wake_thread(). See the comment there which explains the
1101 if (unlikely(irqd_irq_inprogress(&desc->irq_data))) {
1102 raw_spin_unlock_irq(&desc->lock);
1103 chip_bus_sync_unlock(desc);
1109 * Now check again, whether the thread should run. Otherwise
1110 * we would clear the threads_oneshot bit of this thread which
1113 if (test_bit(IRQTF_RUNTHREAD, &action->thread_flags))
1116 desc->threads_oneshot &= ~action->thread_mask;
1118 if (!desc->threads_oneshot && !irqd_irq_disabled(&desc->irq_data) &&
1119 irqd_irq_masked(&desc->irq_data))
1120 unmask_threaded_irq(desc);
1123 raw_spin_unlock_irq(&desc->lock);
1124 chip_bus_sync_unlock(desc);
1129 * Check whether we need to change the affinity of the interrupt thread.
1132 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
1137 if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags))
1141 * In case we are out of memory we set IRQTF_AFFINITY again and
1142 * try again next time
1144 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {
1145 set_bit(IRQTF_AFFINITY, &action->thread_flags);
1149 raw_spin_lock_irq(&desc->lock);
1151 * This code is triggered unconditionally. Check the affinity
1152 * mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
1154 if (cpumask_available(desc->irq_common_data.affinity)) {
1155 const struct cpumask *m;
1157 m = irq_data_get_effective_affinity_mask(&desc->irq_data);
1158 cpumask_copy(mask, m);
1162 raw_spin_unlock_irq(&desc->lock);
1165 set_cpus_allowed_ptr(current, mask);
1166 free_cpumask_var(mask);
1170 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { }
1174 * Interrupts which are not explicitly requested as threaded
1175 * interrupts rely on the implicit bh/preempt disable of the hard irq
1176 * context. So we need to disable bh here to avoid deadlocks and other
1180 irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
1185 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
1186 local_irq_disable();
1187 ret = action->thread_fn(action->irq, action->dev_id);
1188 if (ret == IRQ_HANDLED)
1189 atomic_inc(&desc->threads_handled);
1191 irq_finalize_oneshot(desc, action);
1192 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
1199 * Interrupts explicitly requested as threaded interrupts want to be
1200 * preemptible - many of them need to sleep and wait for slow busses to
1203 static irqreturn_t irq_thread_fn(struct irq_desc *desc,
1204 struct irqaction *action)
1208 ret = action->thread_fn(action->irq, action->dev_id);
1209 if (ret == IRQ_HANDLED)
1210 atomic_inc(&desc->threads_handled);
1212 irq_finalize_oneshot(desc, action);
1216 static void wake_threads_waitq(struct irq_desc *desc)
1218 if (atomic_dec_and_test(&desc->threads_active))
1219 wake_up(&desc->wait_for_threads);
1222 static void irq_thread_dtor(struct callback_head *unused)
1224 struct task_struct *tsk = current;
1225 struct irq_desc *desc;
1226 struct irqaction *action;
1228 if (WARN_ON_ONCE(!(current->flags & PF_EXITING)))
1231 action = kthread_data(tsk);
1233 pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
1234 tsk->comm, tsk->pid, action->irq);
1237 desc = irq_to_desc(action->irq);
1239 * If IRQTF_RUNTHREAD is set, we need to decrement
1240 * desc->threads_active and wake possible waiters.
1242 if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
1243 wake_threads_waitq(desc);
1245 /* Prevent a stale desc->threads_oneshot */
1246 irq_finalize_oneshot(desc, action);
1249 static void irq_wake_secondary(struct irq_desc *desc, struct irqaction *action)
1251 struct irqaction *secondary = action->secondary;
1253 if (WARN_ON_ONCE(!secondary))
1256 raw_spin_lock_irq(&desc->lock);
1257 __irq_wake_thread(desc, secondary);
1258 raw_spin_unlock_irq(&desc->lock);
1262 * Internal function to notify that a interrupt thread is ready.
1264 static void irq_thread_set_ready(struct irq_desc *desc,
1265 struct irqaction *action)
1267 set_bit(IRQTF_READY, &action->thread_flags);
1268 wake_up(&desc->wait_for_threads);
1272 * Internal function to wake up a interrupt thread and wait until it is
1275 static void wake_up_and_wait_for_irq_thread_ready(struct irq_desc *desc,
1276 struct irqaction *action)
1278 if (!action || !action->thread)
1281 wake_up_process(action->thread);
1282 wait_event(desc->wait_for_threads,
1283 test_bit(IRQTF_READY, &action->thread_flags));
1287 * Interrupt handler thread
1289 static int irq_thread(void *data)
1291 struct callback_head on_exit_work;
1292 struct irqaction *action = data;
1293 struct irq_desc *desc = irq_to_desc(action->irq);
1294 irqreturn_t (*handler_fn)(struct irq_desc *desc,
1295 struct irqaction *action);
1297 irq_thread_set_ready(desc, action);
1299 sched_set_fifo(current);
1301 if (force_irqthreads() && test_bit(IRQTF_FORCED_THREAD,
1302 &action->thread_flags))
1303 handler_fn = irq_forced_thread_fn;
1305 handler_fn = irq_thread_fn;
1307 init_task_work(&on_exit_work, irq_thread_dtor);
1308 task_work_add(current, &on_exit_work, TWA_NONE);
1310 irq_thread_check_affinity(desc, action);
1312 while (!irq_wait_for_interrupt(action)) {
1313 irqreturn_t action_ret;
1315 irq_thread_check_affinity(desc, action);
1317 action_ret = handler_fn(desc, action);
1318 if (action_ret == IRQ_WAKE_THREAD)
1319 irq_wake_secondary(desc, action);
1321 wake_threads_waitq(desc);
1325 * This is the regular exit path. __free_irq() is stopping the
1326 * thread via kthread_stop() after calling
1327 * synchronize_hardirq(). So neither IRQTF_RUNTHREAD nor the
1328 * oneshot mask bit can be set.
1330 task_work_cancel(current, irq_thread_dtor);
1335 * irq_wake_thread - wake the irq thread for the action identified by dev_id
1336 * @irq: Interrupt line
1337 * @dev_id: Device identity for which the thread should be woken
1340 void irq_wake_thread(unsigned int irq, void *dev_id)
1342 struct irq_desc *desc = irq_to_desc(irq);
1343 struct irqaction *action;
1344 unsigned long flags;
1346 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1349 raw_spin_lock_irqsave(&desc->lock, flags);
1350 for_each_action_of_desc(desc, action) {
1351 if (action->dev_id == dev_id) {
1353 __irq_wake_thread(desc, action);
1357 raw_spin_unlock_irqrestore(&desc->lock, flags);
1359 EXPORT_SYMBOL_GPL(irq_wake_thread);
1361 static int irq_setup_forced_threading(struct irqaction *new)
1363 if (!force_irqthreads())
1365 if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))
1369 * No further action required for interrupts which are requested as
1370 * threaded interrupts already
1372 if (new->handler == irq_default_primary_handler)
1375 new->flags |= IRQF_ONESHOT;
1378 * Handle the case where we have a real primary handler and a
1379 * thread handler. We force thread them as well by creating a
1382 if (new->handler && new->thread_fn) {
1383 /* Allocate the secondary action */
1384 new->secondary = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
1385 if (!new->secondary)
1387 new->secondary->handler = irq_forced_secondary_handler;
1388 new->secondary->thread_fn = new->thread_fn;
1389 new->secondary->dev_id = new->dev_id;
1390 new->secondary->irq = new->irq;
1391 new->secondary->name = new->name;
1393 /* Deal with the primary handler */
1394 set_bit(IRQTF_FORCED_THREAD, &new->thread_flags);
1395 new->thread_fn = new->handler;
1396 new->handler = irq_default_primary_handler;
1400 static int irq_request_resources(struct irq_desc *desc)
1402 struct irq_data *d = &desc->irq_data;
1403 struct irq_chip *c = d->chip;
1405 return c->irq_request_resources ? c->irq_request_resources(d) : 0;
1408 static void irq_release_resources(struct irq_desc *desc)
1410 struct irq_data *d = &desc->irq_data;
1411 struct irq_chip *c = d->chip;
1413 if (c->irq_release_resources)
1414 c->irq_release_resources(d);
1417 static bool irq_supports_nmi(struct irq_desc *desc)
1419 struct irq_data *d = irq_desc_get_irq_data(desc);
1421 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1422 /* Only IRQs directly managed by the root irqchip can be set as NMI */
1426 /* Don't support NMIs for chips behind a slow bus */
1427 if (d->chip->irq_bus_lock || d->chip->irq_bus_sync_unlock)
1430 return d->chip->flags & IRQCHIP_SUPPORTS_NMI;
1433 static int irq_nmi_setup(struct irq_desc *desc)
1435 struct irq_data *d = irq_desc_get_irq_data(desc);
1436 struct irq_chip *c = d->chip;
1438 return c->irq_nmi_setup ? c->irq_nmi_setup(d) : -EINVAL;
1441 static void irq_nmi_teardown(struct irq_desc *desc)
1443 struct irq_data *d = irq_desc_get_irq_data(desc);
1444 struct irq_chip *c = d->chip;
1446 if (c->irq_nmi_teardown)
1447 c->irq_nmi_teardown(d);
1451 setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
1453 struct task_struct *t;
1456 t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
1459 t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq,
1467 * We keep the reference to the task struct even if
1468 * the thread dies to avoid that the interrupt code
1469 * references an already freed task_struct.
1471 new->thread = get_task_struct(t);
1473 * Tell the thread to set its affinity. This is
1474 * important for shared interrupt handlers as we do
1475 * not invoke setup_affinity() for the secondary
1476 * handlers as everything is already set up. Even for
1477 * interrupts marked with IRQF_NO_BALANCE this is
1478 * correct as we want the thread to move to the cpu(s)
1479 * on which the requesting code placed the interrupt.
1481 set_bit(IRQTF_AFFINITY, &new->thread_flags);
1486 * Internal function to register an irqaction - typically used to
1487 * allocate special interrupts that are part of the architecture.
1491 * desc->request_mutex Provides serialization against a concurrent free_irq()
1492 * chip_bus_lock Provides serialization for slow bus operations
1493 * desc->lock Provides serialization against hard interrupts
1495 * chip_bus_lock and desc->lock are sufficient for all other management and
1496 * interrupt related functions. desc->request_mutex solely serializes
1497 * request/free_irq().
1500 __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
1502 struct irqaction *old, **old_ptr;
1503 unsigned long flags, thread_mask = 0;
1504 int ret, nested, shared = 0;
1509 if (desc->irq_data.chip == &no_irq_chip)
1511 if (!try_module_get(desc->owner))
1517 * If the trigger type is not specified by the caller,
1518 * then use the default for this interrupt.
1520 if (!(new->flags & IRQF_TRIGGER_MASK))
1521 new->flags |= irqd_get_trigger_type(&desc->irq_data);
1524 * Check whether the interrupt nests into another interrupt
1527 nested = irq_settings_is_nested_thread(desc);
1529 if (!new->thread_fn) {
1534 * Replace the primary handler which was provided from
1535 * the driver for non nested interrupt handling by the
1536 * dummy function which warns when called.
1538 new->handler = irq_nested_primary_handler;
1540 if (irq_settings_can_thread(desc)) {
1541 ret = irq_setup_forced_threading(new);
1548 * Create a handler thread when a thread function is supplied
1549 * and the interrupt does not nest into another interrupt
1552 if (new->thread_fn && !nested) {
1553 ret = setup_irq_thread(new, irq, false);
1556 if (new->secondary) {
1557 ret = setup_irq_thread(new->secondary, irq, true);
1564 * Drivers are often written to work w/o knowledge about the
1565 * underlying irq chip implementation, so a request for a
1566 * threaded irq without a primary hard irq context handler
1567 * requires the ONESHOT flag to be set. Some irq chips like
1568 * MSI based interrupts are per se one shot safe. Check the
1569 * chip flags, so we can avoid the unmask dance at the end of
1570 * the threaded handler for those.
1572 if (desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)
1573 new->flags &= ~IRQF_ONESHOT;
1576 * Protects against a concurrent __free_irq() call which might wait
1577 * for synchronize_hardirq() to complete without holding the optional
1578 * chip bus lock and desc->lock. Also protects against handing out
1579 * a recycled oneshot thread_mask bit while it's still in use by
1580 * its previous owner.
1582 mutex_lock(&desc->request_mutex);
1585 * Acquire bus lock as the irq_request_resources() callback below
1586 * might rely on the serialization or the magic power management
1587 * functions which are abusing the irq_bus_lock() callback,
1589 chip_bus_lock(desc);
1591 /* First installed action requests resources. */
1592 if (!desc->action) {
1593 ret = irq_request_resources(desc);
1595 pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
1596 new->name, irq, desc->irq_data.chip->name);
1597 goto out_bus_unlock;
1602 * The following block of code has to be executed atomically
1603 * protected against a concurrent interrupt and any of the other
1604 * management calls which are not serialized via
1605 * desc->request_mutex or the optional bus lock.
1607 raw_spin_lock_irqsave(&desc->lock, flags);
1608 old_ptr = &desc->action;
1612 * Can't share interrupts unless both agree to and are
1613 * the same type (level, edge, polarity). So both flag
1614 * fields must have IRQF_SHARED set and the bits which
1615 * set the trigger type must match. Also all must
1617 * Interrupt lines used for NMIs cannot be shared.
1619 unsigned int oldtype;
1621 if (desc->istate & IRQS_NMI) {
1622 pr_err("Invalid attempt to share NMI for %s (irq %d) on irqchip %s.\n",
1623 new->name, irq, desc->irq_data.chip->name);
1629 * If nobody did set the configuration before, inherit
1630 * the one provided by the requester.
1632 if (irqd_trigger_type_was_set(&desc->irq_data)) {
1633 oldtype = irqd_get_trigger_type(&desc->irq_data);
1635 oldtype = new->flags & IRQF_TRIGGER_MASK;
1636 irqd_set_trigger_type(&desc->irq_data, oldtype);
1639 if (!((old->flags & new->flags) & IRQF_SHARED) ||
1640 (oldtype != (new->flags & IRQF_TRIGGER_MASK)) ||
1641 ((old->flags ^ new->flags) & IRQF_ONESHOT))
1644 /* All handlers must agree on per-cpuness */
1645 if ((old->flags & IRQF_PERCPU) !=
1646 (new->flags & IRQF_PERCPU))
1649 /* add new interrupt at end of irq queue */
1652 * Or all existing action->thread_mask bits,
1653 * so we can find the next zero bit for this
1656 thread_mask |= old->thread_mask;
1657 old_ptr = &old->next;
1664 * Setup the thread mask for this irqaction for ONESHOT. For
1665 * !ONESHOT irqs the thread mask is 0 so we can avoid a
1666 * conditional in irq_wake_thread().
1668 if (new->flags & IRQF_ONESHOT) {
1670 * Unlikely to have 32 resp 64 irqs sharing one line,
1673 if (thread_mask == ~0UL) {
1678 * The thread_mask for the action is or'ed to
1679 * desc->thread_active to indicate that the
1680 * IRQF_ONESHOT thread handler has been woken, but not
1681 * yet finished. The bit is cleared when a thread
1682 * completes. When all threads of a shared interrupt
1683 * line have completed desc->threads_active becomes
1684 * zero and the interrupt line is unmasked. See
1685 * handle.c:irq_wake_thread() for further information.
1687 * If no thread is woken by primary (hard irq context)
1688 * interrupt handlers, then desc->threads_active is
1689 * also checked for zero to unmask the irq line in the
1690 * affected hard irq flow handlers
1691 * (handle_[fasteoi|level]_irq).
1693 * The new action gets the first zero bit of
1694 * thread_mask assigned. See the loop above which or's
1695 * all existing action->thread_mask bits.
1697 new->thread_mask = 1UL << ffz(thread_mask);
1699 } else if (new->handler == irq_default_primary_handler &&
1700 !(desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)) {
1702 * The interrupt was requested with handler = NULL, so
1703 * we use the default primary handler for it. But it
1704 * does not have the oneshot flag set. In combination
1705 * with level interrupts this is deadly, because the
1706 * default primary handler just wakes the thread, then
1707 * the irq lines is reenabled, but the device still
1708 * has the level irq asserted. Rinse and repeat....
1710 * While this works for edge type interrupts, we play
1711 * it safe and reject unconditionally because we can't
1712 * say for sure which type this interrupt really
1713 * has. The type flags are unreliable as the
1714 * underlying chip implementation can override them.
1716 pr_err("Threaded irq requested with handler=NULL and !ONESHOT for %s (irq %d)\n",
1723 /* Setup the type (level, edge polarity) if configured: */
1724 if (new->flags & IRQF_TRIGGER_MASK) {
1725 ret = __irq_set_trigger(desc,
1726 new->flags & IRQF_TRIGGER_MASK);
1733 * Activate the interrupt. That activation must happen
1734 * independently of IRQ_NOAUTOEN. request_irq() can fail
1735 * and the callers are supposed to handle
1736 * that. enable_irq() of an interrupt requested with
1737 * IRQ_NOAUTOEN is not supposed to fail. The activation
1738 * keeps it in shutdown mode, it merily associates
1739 * resources if necessary and if that's not possible it
1740 * fails. Interrupts which are in managed shutdown mode
1741 * will simply ignore that activation request.
1743 ret = irq_activate(desc);
1747 desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \
1748 IRQS_ONESHOT | IRQS_WAITING);
1749 irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
1751 if (new->flags & IRQF_PERCPU) {
1752 irqd_set(&desc->irq_data, IRQD_PER_CPU);
1753 irq_settings_set_per_cpu(desc);
1754 if (new->flags & IRQF_NO_DEBUG)
1755 irq_settings_set_no_debug(desc);
1759 irq_settings_set_no_debug(desc);
1761 if (new->flags & IRQF_ONESHOT)
1762 desc->istate |= IRQS_ONESHOT;
1764 /* Exclude IRQ from balancing if requested */
1765 if (new->flags & IRQF_NOBALANCING) {
1766 irq_settings_set_no_balancing(desc);
1767 irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
1770 if (!(new->flags & IRQF_NO_AUTOEN) &&
1771 irq_settings_can_autoenable(desc)) {
1772 irq_startup(desc, IRQ_RESEND, IRQ_START_COND);
1775 * Shared interrupts do not go well with disabling
1776 * auto enable. The sharing interrupt might request
1777 * it while it's still disabled and then wait for
1778 * interrupts forever.
1780 WARN_ON_ONCE(new->flags & IRQF_SHARED);
1781 /* Undo nested disables: */
1785 } else if (new->flags & IRQF_TRIGGER_MASK) {
1786 unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK;
1787 unsigned int omsk = irqd_get_trigger_type(&desc->irq_data);
1790 /* hope the handler works with current trigger mode */
1791 pr_warn("irq %d uses trigger mode %u; requested %u\n",
1797 irq_pm_install_action(desc, new);
1799 /* Reset broken irq detection when installing new handler */
1800 desc->irq_count = 0;
1801 desc->irqs_unhandled = 0;
1804 * Check whether we disabled the irq via the spurious handler
1805 * before. Reenable it and give it another chance.
1807 if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) {
1808 desc->istate &= ~IRQS_SPURIOUS_DISABLED;
1812 raw_spin_unlock_irqrestore(&desc->lock, flags);
1813 chip_bus_sync_unlock(desc);
1814 mutex_unlock(&desc->request_mutex);
1816 irq_setup_timings(desc, new);
1818 wake_up_and_wait_for_irq_thread_ready(desc, new);
1819 wake_up_and_wait_for_irq_thread_ready(desc, new->secondary);
1821 register_irq_proc(irq, desc);
1823 register_handler_proc(irq, new);
1827 if (!(new->flags & IRQF_PROBE_SHARED)) {
1828 pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
1829 irq, new->flags, new->name, old->flags, old->name);
1830 #ifdef CONFIG_DEBUG_SHIRQ
1837 raw_spin_unlock_irqrestore(&desc->lock, flags);
1840 irq_release_resources(desc);
1842 chip_bus_sync_unlock(desc);
1843 mutex_unlock(&desc->request_mutex);
1847 struct task_struct *t = new->thread;
1853 if (new->secondary && new->secondary->thread) {
1854 struct task_struct *t = new->secondary->thread;
1856 new->secondary->thread = NULL;
1861 module_put(desc->owner);
1866 * Internal function to unregister an irqaction - used to free
1867 * regular and special interrupts that are part of the architecture.
1869 static struct irqaction *__free_irq(struct irq_desc *desc, void *dev_id)
1871 unsigned irq = desc->irq_data.irq;
1872 struct irqaction *action, **action_ptr;
1873 unsigned long flags;
1875 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
1877 mutex_lock(&desc->request_mutex);
1878 chip_bus_lock(desc);
1879 raw_spin_lock_irqsave(&desc->lock, flags);
1882 * There can be multiple actions per IRQ descriptor, find the right
1883 * one based on the dev_id:
1885 action_ptr = &desc->action;
1887 action = *action_ptr;
1890 WARN(1, "Trying to free already-free IRQ %d\n", irq);
1891 raw_spin_unlock_irqrestore(&desc->lock, flags);
1892 chip_bus_sync_unlock(desc);
1893 mutex_unlock(&desc->request_mutex);
1897 if (action->dev_id == dev_id)
1899 action_ptr = &action->next;
1902 /* Found it - now remove it from the list of entries: */
1903 *action_ptr = action->next;
1905 irq_pm_remove_action(desc, action);
1907 /* If this was the last handler, shut down the IRQ line: */
1908 if (!desc->action) {
1909 irq_settings_clr_disable_unlazy(desc);
1910 /* Only shutdown. Deactivate after synchronize_hardirq() */
1915 /* make sure affinity_hint is cleaned up */
1916 if (WARN_ON_ONCE(desc->affinity_hint))
1917 desc->affinity_hint = NULL;
1920 raw_spin_unlock_irqrestore(&desc->lock, flags);
1922 * Drop bus_lock here so the changes which were done in the chip
1923 * callbacks above are synced out to the irq chips which hang
1924 * behind a slow bus (I2C, SPI) before calling synchronize_hardirq().
1926 * Aside of that the bus_lock can also be taken from the threaded
1927 * handler in irq_finalize_oneshot() which results in a deadlock
1928 * because kthread_stop() would wait forever for the thread to
1929 * complete, which is blocked on the bus lock.
1931 * The still held desc->request_mutex() protects against a
1932 * concurrent request_irq() of this irq so the release of resources
1933 * and timing data is properly serialized.
1935 chip_bus_sync_unlock(desc);
1937 unregister_handler_proc(irq, action);
1940 * Make sure it's not being used on another CPU and if the chip
1941 * supports it also make sure that there is no (not yet serviced)
1942 * interrupt in flight at the hardware level.
1944 __synchronize_hardirq(desc, true);
1946 #ifdef CONFIG_DEBUG_SHIRQ
1948 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
1949 * event to happen even now it's being freed, so let's make sure that
1950 * is so by doing an extra call to the handler ....
1952 * ( We do this after actually deregistering it, to make sure that a
1953 * 'real' IRQ doesn't run in parallel with our fake. )
1955 if (action->flags & IRQF_SHARED) {
1956 local_irq_save(flags);
1957 action->handler(irq, dev_id);
1958 local_irq_restore(flags);
1963 * The action has already been removed above, but the thread writes
1964 * its oneshot mask bit when it completes. Though request_mutex is
1965 * held across this which prevents __setup_irq() from handing out
1966 * the same bit to a newly requested action.
1968 if (action->thread) {
1969 kthread_stop(action->thread);
1970 put_task_struct(action->thread);
1971 if (action->secondary && action->secondary->thread) {
1972 kthread_stop(action->secondary->thread);
1973 put_task_struct(action->secondary->thread);
1977 /* Last action releases resources */
1978 if (!desc->action) {
1980 * Reacquire bus lock as irq_release_resources() might
1981 * require it to deallocate resources over the slow bus.
1983 chip_bus_lock(desc);
1985 * There is no interrupt on the fly anymore. Deactivate it
1988 raw_spin_lock_irqsave(&desc->lock, flags);
1989 irq_domain_deactivate_irq(&desc->irq_data);
1990 raw_spin_unlock_irqrestore(&desc->lock, flags);
1992 irq_release_resources(desc);
1993 chip_bus_sync_unlock(desc);
1994 irq_remove_timings(desc);
1997 mutex_unlock(&desc->request_mutex);
1999 irq_chip_pm_put(&desc->irq_data);
2000 module_put(desc->owner);
2001 kfree(action->secondary);
2006 * free_irq - free an interrupt allocated with request_irq
2007 * @irq: Interrupt line to free
2008 * @dev_id: Device identity to free
2010 * Remove an interrupt handler. The handler is removed and if the
2011 * interrupt line is no longer in use by any driver it is disabled.
2012 * On a shared IRQ the caller must ensure the interrupt is disabled
2013 * on the card it drives before calling this function. The function
2014 * does not return until any executing interrupts for this IRQ
2017 * This function must not be called from interrupt context.
2019 * Returns the devname argument passed to request_irq.
2021 const void *free_irq(unsigned int irq, void *dev_id)
2023 struct irq_desc *desc = irq_to_desc(irq);
2024 struct irqaction *action;
2025 const char *devname;
2027 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2031 if (WARN_ON(desc->affinity_notify))
2032 desc->affinity_notify = NULL;
2035 action = __free_irq(desc, dev_id);
2040 devname = action->name;
2044 EXPORT_SYMBOL(free_irq);
2046 /* This function must be called with desc->lock held */
2047 static const void *__cleanup_nmi(unsigned int irq, struct irq_desc *desc)
2049 const char *devname = NULL;
2051 desc->istate &= ~IRQS_NMI;
2053 if (!WARN_ON(desc->action == NULL)) {
2054 irq_pm_remove_action(desc, desc->action);
2055 devname = desc->action->name;
2056 unregister_handler_proc(irq, desc->action);
2058 kfree(desc->action);
2059 desc->action = NULL;
2062 irq_settings_clr_disable_unlazy(desc);
2063 irq_shutdown_and_deactivate(desc);
2065 irq_release_resources(desc);
2067 irq_chip_pm_put(&desc->irq_data);
2068 module_put(desc->owner);
2073 const void *free_nmi(unsigned int irq, void *dev_id)
2075 struct irq_desc *desc = irq_to_desc(irq);
2076 unsigned long flags;
2077 const void *devname;
2079 if (!desc || WARN_ON(!(desc->istate & IRQS_NMI)))
2082 if (WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2085 /* NMI still enabled */
2086 if (WARN_ON(desc->depth == 0))
2087 disable_nmi_nosync(irq);
2089 raw_spin_lock_irqsave(&desc->lock, flags);
2091 irq_nmi_teardown(desc);
2092 devname = __cleanup_nmi(irq, desc);
2094 raw_spin_unlock_irqrestore(&desc->lock, flags);
2100 * request_threaded_irq - allocate an interrupt line
2101 * @irq: Interrupt line to allocate
2102 * @handler: Function to be called when the IRQ occurs.
2103 * Primary handler for threaded interrupts.
2104 * If handler is NULL and thread_fn != NULL
2105 * the default primary handler is installed.
2106 * @thread_fn: Function called from the irq handler thread
2107 * If NULL, no irq thread is created
2108 * @irqflags: Interrupt type flags
2109 * @devname: An ascii name for the claiming device
2110 * @dev_id: A cookie passed back to the handler function
2112 * This call allocates interrupt resources and enables the
2113 * interrupt line and IRQ handling. From the point this
2114 * call is made your handler function may be invoked. Since
2115 * your handler function must clear any interrupt the board
2116 * raises, you must take care both to initialise your hardware
2117 * and to set up the interrupt handler in the right order.
2119 * If you want to set up a threaded irq handler for your device
2120 * then you need to supply @handler and @thread_fn. @handler is
2121 * still called in hard interrupt context and has to check
2122 * whether the interrupt originates from the device. If yes it
2123 * needs to disable the interrupt on the device and return
2124 * IRQ_WAKE_THREAD which will wake up the handler thread and run
2125 * @thread_fn. This split handler design is necessary to support
2126 * shared interrupts.
2128 * Dev_id must be globally unique. Normally the address of the
2129 * device data structure is used as the cookie. Since the handler
2130 * receives this value it makes sense to use it.
2132 * If your interrupt is shared you must pass a non NULL dev_id
2133 * as this is required when freeing the interrupt.
2137 * IRQF_SHARED Interrupt is shared
2138 * IRQF_TRIGGER_* Specify active edge(s) or level
2139 * IRQF_ONESHOT Run thread_fn with interrupt line masked
2141 int request_threaded_irq(unsigned int irq, irq_handler_t handler,
2142 irq_handler_t thread_fn, unsigned long irqflags,
2143 const char *devname, void *dev_id)
2145 struct irqaction *action;
2146 struct irq_desc *desc;
2149 if (irq == IRQ_NOTCONNECTED)
2153 * Sanity-check: shared interrupts must pass in a real dev-ID,
2154 * otherwise we'll have trouble later trying to figure out
2155 * which interrupt is which (messes up the interrupt freeing
2158 * Also shared interrupts do not go well with disabling auto enable.
2159 * The sharing interrupt might request it while it's still disabled
2160 * and then wait for interrupts forever.
2162 * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
2163 * it cannot be set along with IRQF_NO_SUSPEND.
2165 if (((irqflags & IRQF_SHARED) && !dev_id) ||
2166 ((irqflags & IRQF_SHARED) && (irqflags & IRQF_NO_AUTOEN)) ||
2167 (!(irqflags & IRQF_SHARED) && (irqflags & IRQF_COND_SUSPEND)) ||
2168 ((irqflags & IRQF_NO_SUSPEND) && (irqflags & IRQF_COND_SUSPEND)))
2171 desc = irq_to_desc(irq);
2175 if (!irq_settings_can_request(desc) ||
2176 WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2182 handler = irq_default_primary_handler;
2185 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2189 action->handler = handler;
2190 action->thread_fn = thread_fn;
2191 action->flags = irqflags;
2192 action->name = devname;
2193 action->dev_id = dev_id;
2195 retval = irq_chip_pm_get(&desc->irq_data);
2201 retval = __setup_irq(irq, desc, action);
2204 irq_chip_pm_put(&desc->irq_data);
2205 kfree(action->secondary);
2209 #ifdef CONFIG_DEBUG_SHIRQ_FIXME
2210 if (!retval && (irqflags & IRQF_SHARED)) {
2212 * It's a shared IRQ -- the driver ought to be prepared for it
2213 * to happen immediately, so let's make sure....
2214 * We disable the irq to make sure that a 'real' IRQ doesn't
2215 * run in parallel with our fake.
2217 unsigned long flags;
2220 local_irq_save(flags);
2222 handler(irq, dev_id);
2224 local_irq_restore(flags);
2230 EXPORT_SYMBOL(request_threaded_irq);
2233 * request_any_context_irq - allocate an interrupt line
2234 * @irq: Interrupt line to allocate
2235 * @handler: Function to be called when the IRQ occurs.
2236 * Threaded handler for threaded interrupts.
2237 * @flags: Interrupt type flags
2238 * @name: An ascii name for the claiming device
2239 * @dev_id: A cookie passed back to the handler function
2241 * This call allocates interrupt resources and enables the
2242 * interrupt line and IRQ handling. It selects either a
2243 * hardirq or threaded handling method depending on the
2246 * On failure, it returns a negative value. On success,
2247 * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
2249 int request_any_context_irq(unsigned int irq, irq_handler_t handler,
2250 unsigned long flags, const char *name, void *dev_id)
2252 struct irq_desc *desc;
2255 if (irq == IRQ_NOTCONNECTED)
2258 desc = irq_to_desc(irq);
2262 if (irq_settings_is_nested_thread(desc)) {
2263 ret = request_threaded_irq(irq, NULL, handler,
2264 flags, name, dev_id);
2265 return !ret ? IRQC_IS_NESTED : ret;
2268 ret = request_irq(irq, handler, flags, name, dev_id);
2269 return !ret ? IRQC_IS_HARDIRQ : ret;
2271 EXPORT_SYMBOL_GPL(request_any_context_irq);
2274 * request_nmi - allocate an interrupt line for NMI delivery
2275 * @irq: Interrupt line to allocate
2276 * @handler: Function to be called when the IRQ occurs.
2277 * Threaded handler for threaded interrupts.
2278 * @irqflags: Interrupt type flags
2279 * @name: An ascii name for the claiming device
2280 * @dev_id: A cookie passed back to the handler function
2282 * This call allocates interrupt resources and enables the
2283 * interrupt line and IRQ handling. It sets up the IRQ line
2284 * to be handled as an NMI.
2286 * An interrupt line delivering NMIs cannot be shared and IRQ handling
2287 * cannot be threaded.
2289 * Interrupt lines requested for NMI delivering must produce per cpu
2290 * interrupts and have auto enabling setting disabled.
2292 * Dev_id must be globally unique. Normally the address of the
2293 * device data structure is used as the cookie. Since the handler
2294 * receives this value it makes sense to use it.
2296 * If the interrupt line cannot be used to deliver NMIs, function
2297 * will fail and return a negative value.
2299 int request_nmi(unsigned int irq, irq_handler_t handler,
2300 unsigned long irqflags, const char *name, void *dev_id)
2302 struct irqaction *action;
2303 struct irq_desc *desc;
2304 unsigned long flags;
2307 if (irq == IRQ_NOTCONNECTED)
2310 /* NMI cannot be shared, used for Polling */
2311 if (irqflags & (IRQF_SHARED | IRQF_COND_SUSPEND | IRQF_IRQPOLL))
2314 if (!(irqflags & IRQF_PERCPU))
2320 desc = irq_to_desc(irq);
2322 if (!desc || (irq_settings_can_autoenable(desc) &&
2323 !(irqflags & IRQF_NO_AUTOEN)) ||
2324 !irq_settings_can_request(desc) ||
2325 WARN_ON(irq_settings_is_per_cpu_devid(desc)) ||
2326 !irq_supports_nmi(desc))
2329 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2333 action->handler = handler;
2334 action->flags = irqflags | IRQF_NO_THREAD | IRQF_NOBALANCING;
2335 action->name = name;
2336 action->dev_id = dev_id;
2338 retval = irq_chip_pm_get(&desc->irq_data);
2342 retval = __setup_irq(irq, desc, action);
2346 raw_spin_lock_irqsave(&desc->lock, flags);
2348 /* Setup NMI state */
2349 desc->istate |= IRQS_NMI;
2350 retval = irq_nmi_setup(desc);
2352 __cleanup_nmi(irq, desc);
2353 raw_spin_unlock_irqrestore(&desc->lock, flags);
2357 raw_spin_unlock_irqrestore(&desc->lock, flags);
2362 irq_chip_pm_put(&desc->irq_data);
2369 void enable_percpu_irq(unsigned int irq, unsigned int type)
2371 unsigned int cpu = smp_processor_id();
2372 unsigned long flags;
2373 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2379 * If the trigger type is not specified by the caller, then
2380 * use the default for this interrupt.
2382 type &= IRQ_TYPE_SENSE_MASK;
2383 if (type == IRQ_TYPE_NONE)
2384 type = irqd_get_trigger_type(&desc->irq_data);
2386 if (type != IRQ_TYPE_NONE) {
2389 ret = __irq_set_trigger(desc, type);
2392 WARN(1, "failed to set type for IRQ%d\n", irq);
2397 irq_percpu_enable(desc, cpu);
2399 irq_put_desc_unlock(desc, flags);
2401 EXPORT_SYMBOL_GPL(enable_percpu_irq);
2403 void enable_percpu_nmi(unsigned int irq, unsigned int type)
2405 enable_percpu_irq(irq, type);
2409 * irq_percpu_is_enabled - Check whether the per cpu irq is enabled
2410 * @irq: Linux irq number to check for
2412 * Must be called from a non migratable context. Returns the enable
2413 * state of a per cpu interrupt on the current cpu.
2415 bool irq_percpu_is_enabled(unsigned int irq)
2417 unsigned int cpu = smp_processor_id();
2418 struct irq_desc *desc;
2419 unsigned long flags;
2422 desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2426 is_enabled = cpumask_test_cpu(cpu, desc->percpu_enabled);
2427 irq_put_desc_unlock(desc, flags);
2431 EXPORT_SYMBOL_GPL(irq_percpu_is_enabled);
2433 void disable_percpu_irq(unsigned int irq)
2435 unsigned int cpu = smp_processor_id();
2436 unsigned long flags;
2437 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2442 irq_percpu_disable(desc, cpu);
2443 irq_put_desc_unlock(desc, flags);
2445 EXPORT_SYMBOL_GPL(disable_percpu_irq);
2447 void disable_percpu_nmi(unsigned int irq)
2449 disable_percpu_irq(irq);
2453 * Internal function to unregister a percpu irqaction.
2455 static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_id)
2457 struct irq_desc *desc = irq_to_desc(irq);
2458 struct irqaction *action;
2459 unsigned long flags;
2461 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
2466 raw_spin_lock_irqsave(&desc->lock, flags);
2468 action = desc->action;
2469 if (!action || action->percpu_dev_id != dev_id) {
2470 WARN(1, "Trying to free already-free IRQ %d\n", irq);
2474 if (!cpumask_empty(desc->percpu_enabled)) {
2475 WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
2476 irq, cpumask_first(desc->percpu_enabled));
2480 /* Found it - now remove it from the list of entries: */
2481 desc->action = NULL;
2483 desc->istate &= ~IRQS_NMI;
2485 raw_spin_unlock_irqrestore(&desc->lock, flags);
2487 unregister_handler_proc(irq, action);
2489 irq_chip_pm_put(&desc->irq_data);
2490 module_put(desc->owner);
2494 raw_spin_unlock_irqrestore(&desc->lock, flags);
2499 * remove_percpu_irq - free a per-cpu interrupt
2500 * @irq: Interrupt line to free
2501 * @act: irqaction for the interrupt
2503 * Used to remove interrupts statically setup by the early boot process.
2505 void remove_percpu_irq(unsigned int irq, struct irqaction *act)
2507 struct irq_desc *desc = irq_to_desc(irq);
2509 if (desc && irq_settings_is_per_cpu_devid(desc))
2510 __free_percpu_irq(irq, act->percpu_dev_id);
2514 * free_percpu_irq - free an interrupt allocated with request_percpu_irq
2515 * @irq: Interrupt line to free
2516 * @dev_id: Device identity to free
2518 * Remove a percpu interrupt handler. The handler is removed, but
2519 * the interrupt line is not disabled. This must be done on each
2520 * CPU before calling this function. The function does not return
2521 * until any executing interrupts for this IRQ have completed.
2523 * This function must not be called from interrupt context.
2525 void free_percpu_irq(unsigned int irq, void __percpu *dev_id)
2527 struct irq_desc *desc = irq_to_desc(irq);
2529 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2532 chip_bus_lock(desc);
2533 kfree(__free_percpu_irq(irq, dev_id));
2534 chip_bus_sync_unlock(desc);
2536 EXPORT_SYMBOL_GPL(free_percpu_irq);
2538 void free_percpu_nmi(unsigned int irq, void __percpu *dev_id)
2540 struct irq_desc *desc = irq_to_desc(irq);
2542 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2545 if (WARN_ON(!(desc->istate & IRQS_NMI)))
2548 kfree(__free_percpu_irq(irq, dev_id));
2552 * setup_percpu_irq - setup a per-cpu interrupt
2553 * @irq: Interrupt line to setup
2554 * @act: irqaction for the interrupt
2556 * Used to statically setup per-cpu interrupts in the early boot process.
2558 int setup_percpu_irq(unsigned int irq, struct irqaction *act)
2560 struct irq_desc *desc = irq_to_desc(irq);
2563 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2566 retval = irq_chip_pm_get(&desc->irq_data);
2570 retval = __setup_irq(irq, desc, act);
2573 irq_chip_pm_put(&desc->irq_data);
2579 * __request_percpu_irq - allocate a percpu interrupt line
2580 * @irq: Interrupt line to allocate
2581 * @handler: Function to be called when the IRQ occurs.
2582 * @flags: Interrupt type flags (IRQF_TIMER only)
2583 * @devname: An ascii name for the claiming device
2584 * @dev_id: A percpu cookie passed back to the handler function
2586 * This call allocates interrupt resources and enables the
2587 * interrupt on the local CPU. If the interrupt is supposed to be
2588 * enabled on other CPUs, it has to be done on each CPU using
2589 * enable_percpu_irq().
2591 * Dev_id must be globally unique. It is a per-cpu variable, and
2592 * the handler gets called with the interrupted CPU's instance of
2595 int __request_percpu_irq(unsigned int irq, irq_handler_t handler,
2596 unsigned long flags, const char *devname,
2597 void __percpu *dev_id)
2599 struct irqaction *action;
2600 struct irq_desc *desc;
2606 desc = irq_to_desc(irq);
2607 if (!desc || !irq_settings_can_request(desc) ||
2608 !irq_settings_is_per_cpu_devid(desc))
2611 if (flags && flags != IRQF_TIMER)
2614 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2618 action->handler = handler;
2619 action->flags = flags | IRQF_PERCPU | IRQF_NO_SUSPEND;
2620 action->name = devname;
2621 action->percpu_dev_id = dev_id;
2623 retval = irq_chip_pm_get(&desc->irq_data);
2629 retval = __setup_irq(irq, desc, action);
2632 irq_chip_pm_put(&desc->irq_data);
2638 EXPORT_SYMBOL_GPL(__request_percpu_irq);
2641 * request_percpu_nmi - allocate a percpu interrupt line for NMI delivery
2642 * @irq: Interrupt line to allocate
2643 * @handler: Function to be called when the IRQ occurs.
2644 * @name: An ascii name for the claiming device
2645 * @dev_id: A percpu cookie passed back to the handler function
2647 * This call allocates interrupt resources for a per CPU NMI. Per CPU NMIs
2648 * have to be setup on each CPU by calling prepare_percpu_nmi() before
2649 * being enabled on the same CPU by using enable_percpu_nmi().
2651 * Dev_id must be globally unique. It is a per-cpu variable, and
2652 * the handler gets called with the interrupted CPU's instance of
2655 * Interrupt lines requested for NMI delivering should have auto enabling
2658 * If the interrupt line cannot be used to deliver NMIs, function
2659 * will fail returning a negative value.
2661 int request_percpu_nmi(unsigned int irq, irq_handler_t handler,
2662 const char *name, void __percpu *dev_id)
2664 struct irqaction *action;
2665 struct irq_desc *desc;
2666 unsigned long flags;
2672 desc = irq_to_desc(irq);
2674 if (!desc || !irq_settings_can_request(desc) ||
2675 !irq_settings_is_per_cpu_devid(desc) ||
2676 irq_settings_can_autoenable(desc) ||
2677 !irq_supports_nmi(desc))
2680 /* The line cannot already be NMI */
2681 if (desc->istate & IRQS_NMI)
2684 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2688 action->handler = handler;
2689 action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND | IRQF_NO_THREAD
2691 action->name = name;
2692 action->percpu_dev_id = dev_id;
2694 retval = irq_chip_pm_get(&desc->irq_data);
2698 retval = __setup_irq(irq, desc, action);
2702 raw_spin_lock_irqsave(&desc->lock, flags);
2703 desc->istate |= IRQS_NMI;
2704 raw_spin_unlock_irqrestore(&desc->lock, flags);
2709 irq_chip_pm_put(&desc->irq_data);
2717 * prepare_percpu_nmi - performs CPU local setup for NMI delivery
2718 * @irq: Interrupt line to prepare for NMI delivery
2720 * This call prepares an interrupt line to deliver NMI on the current CPU,
2721 * before that interrupt line gets enabled with enable_percpu_nmi().
2723 * As a CPU local operation, this should be called from non-preemptible
2726 * If the interrupt line cannot be used to deliver NMIs, function
2727 * will fail returning a negative value.
2729 int prepare_percpu_nmi(unsigned int irq)
2731 unsigned long flags;
2732 struct irq_desc *desc;
2735 WARN_ON(preemptible());
2737 desc = irq_get_desc_lock(irq, &flags,
2738 IRQ_GET_DESC_CHECK_PERCPU);
2742 if (WARN(!(desc->istate & IRQS_NMI),
2743 KERN_ERR "prepare_percpu_nmi called for a non-NMI interrupt: irq %u\n",
2749 ret = irq_nmi_setup(desc);
2751 pr_err("Failed to setup NMI delivery: irq %u\n", irq);
2756 irq_put_desc_unlock(desc, flags);
2761 * teardown_percpu_nmi - undoes NMI setup of IRQ line
2762 * @irq: Interrupt line from which CPU local NMI configuration should be
2765 * This call undoes the setup done by prepare_percpu_nmi().
2767 * IRQ line should not be enabled for the current CPU.
2769 * As a CPU local operation, this should be called from non-preemptible
2772 void teardown_percpu_nmi(unsigned int irq)
2774 unsigned long flags;
2775 struct irq_desc *desc;
2777 WARN_ON(preemptible());
2779 desc = irq_get_desc_lock(irq, &flags,
2780 IRQ_GET_DESC_CHECK_PERCPU);
2784 if (WARN_ON(!(desc->istate & IRQS_NMI)))
2787 irq_nmi_teardown(desc);
2789 irq_put_desc_unlock(desc, flags);
2792 int __irq_get_irqchip_state(struct irq_data *data, enum irqchip_irq_state which,
2795 struct irq_chip *chip;
2799 chip = irq_data_get_irq_chip(data);
2800 if (WARN_ON_ONCE(!chip))
2802 if (chip->irq_get_irqchip_state)
2804 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2805 data = data->parent_data;
2812 err = chip->irq_get_irqchip_state(data, which, state);
2817 * irq_get_irqchip_state - returns the irqchip state of a interrupt.
2818 * @irq: Interrupt line that is forwarded to a VM
2819 * @which: One of IRQCHIP_STATE_* the caller wants to know about
2820 * @state: a pointer to a boolean where the state is to be stored
2822 * This call snapshots the internal irqchip state of an
2823 * interrupt, returning into @state the bit corresponding to
2826 * This function should be called with preemption disabled if the
2827 * interrupt controller has per-cpu registers.
2829 int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2832 struct irq_desc *desc;
2833 struct irq_data *data;
2834 unsigned long flags;
2837 desc = irq_get_desc_buslock(irq, &flags, 0);
2841 data = irq_desc_get_irq_data(desc);
2843 err = __irq_get_irqchip_state(data, which, state);
2845 irq_put_desc_busunlock(desc, flags);
2848 EXPORT_SYMBOL_GPL(irq_get_irqchip_state);
2851 * irq_set_irqchip_state - set the state of a forwarded interrupt.
2852 * @irq: Interrupt line that is forwarded to a VM
2853 * @which: State to be restored (one of IRQCHIP_STATE_*)
2854 * @val: Value corresponding to @which
2856 * This call sets the internal irqchip state of an interrupt,
2857 * depending on the value of @which.
2859 * This function should be called with migration disabled if the
2860 * interrupt controller has per-cpu registers.
2862 int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2865 struct irq_desc *desc;
2866 struct irq_data *data;
2867 struct irq_chip *chip;
2868 unsigned long flags;
2871 desc = irq_get_desc_buslock(irq, &flags, 0);
2875 data = irq_desc_get_irq_data(desc);
2878 chip = irq_data_get_irq_chip(data);
2879 if (WARN_ON_ONCE(!chip)) {
2883 if (chip->irq_set_irqchip_state)
2885 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2886 data = data->parent_data;
2893 err = chip->irq_set_irqchip_state(data, which, val);
2896 irq_put_desc_busunlock(desc, flags);
2899 EXPORT_SYMBOL_GPL(irq_set_irqchip_state);
2902 * irq_has_action - Check whether an interrupt is requested
2903 * @irq: The linux irq number
2905 * Returns: A snapshot of the current state
2907 bool irq_has_action(unsigned int irq)
2912 res = irq_desc_has_action(irq_to_desc(irq));
2916 EXPORT_SYMBOL_GPL(irq_has_action);
2919 * irq_check_status_bit - Check whether bits in the irq descriptor status are set
2920 * @irq: The linux irq number
2921 * @bitmask: The bitmask to evaluate
2923 * Returns: True if one of the bits in @bitmask is set
2925 bool irq_check_status_bit(unsigned int irq, unsigned int bitmask)
2927 struct irq_desc *desc;
2931 desc = irq_to_desc(irq);
2933 res = !!(desc->status_use_accessors & bitmask);
2937 EXPORT_SYMBOL_GPL(irq_check_status_bit);