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);
111 static void __synchronize_irq(struct irq_desc *desc)
113 __synchronize_hardirq(desc, true);
115 * We made sure that no hardirq handler is running. Now verify that no
116 * threaded handlers are active.
118 wait_event(desc->wait_for_threads, !atomic_read(&desc->threads_active));
122 * synchronize_irq - wait for pending IRQ handlers (on other CPUs)
123 * @irq: interrupt number to wait for
125 * This function waits for any pending IRQ handlers for this interrupt
126 * to complete before returning. If you use this function while
127 * holding a resource the IRQ handler may need you will deadlock.
129 * Can only be called from preemptible code as it might sleep when
130 * an interrupt thread is associated to @irq.
132 * It optionally makes sure (when the irq chip supports that method)
133 * that the interrupt is not pending in any CPU and waiting for
136 void synchronize_irq(unsigned int irq)
138 struct irq_desc *desc = irq_to_desc(irq);
141 __synchronize_irq(desc);
143 EXPORT_SYMBOL(synchronize_irq);
146 cpumask_var_t irq_default_affinity;
148 static bool __irq_can_set_affinity(struct irq_desc *desc)
150 if (!desc || !irqd_can_balance(&desc->irq_data) ||
151 !desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity)
157 * irq_can_set_affinity - Check if the affinity of a given irq can be set
158 * @irq: Interrupt to check
161 int irq_can_set_affinity(unsigned int irq)
163 return __irq_can_set_affinity(irq_to_desc(irq));
167 * irq_can_set_affinity_usr - Check if affinity of a irq can be set from user space
168 * @irq: Interrupt to check
170 * Like irq_can_set_affinity() above, but additionally checks for the
171 * AFFINITY_MANAGED flag.
173 bool irq_can_set_affinity_usr(unsigned int irq)
175 struct irq_desc *desc = irq_to_desc(irq);
177 return __irq_can_set_affinity(desc) &&
178 !irqd_affinity_is_managed(&desc->irq_data);
182 * irq_set_thread_affinity - Notify irq threads to adjust affinity
183 * @desc: irq descriptor which has affinity changed
185 * We just set IRQTF_AFFINITY and delegate the affinity setting
186 * to the interrupt thread itself. We can not call
187 * set_cpus_allowed_ptr() here as we hold desc->lock and this
188 * code can be called from hard interrupt context.
190 void irq_set_thread_affinity(struct irq_desc *desc)
192 struct irqaction *action;
194 for_each_action_of_desc(desc, action) {
195 if (action->thread) {
196 set_bit(IRQTF_AFFINITY, &action->thread_flags);
197 wake_up_process(action->thread);
199 if (action->secondary && action->secondary->thread) {
200 set_bit(IRQTF_AFFINITY, &action->secondary->thread_flags);
201 wake_up_process(action->secondary->thread);
206 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
207 static void irq_validate_effective_affinity(struct irq_data *data)
209 const struct cpumask *m = irq_data_get_effective_affinity_mask(data);
210 struct irq_chip *chip = irq_data_get_irq_chip(data);
212 if (!cpumask_empty(m))
214 pr_warn_once("irq_chip %s did not update eff. affinity mask of irq %u\n",
215 chip->name, data->irq);
218 static inline void irq_validate_effective_affinity(struct irq_data *data) { }
221 int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
224 struct irq_desc *desc = irq_data_to_desc(data);
225 struct irq_chip *chip = irq_data_get_irq_chip(data);
226 const struct cpumask *prog_mask;
229 static DEFINE_RAW_SPINLOCK(tmp_mask_lock);
230 static struct cpumask tmp_mask;
232 if (!chip || !chip->irq_set_affinity)
235 raw_spin_lock(&tmp_mask_lock);
237 * If this is a managed interrupt and housekeeping is enabled on
238 * it check whether the requested affinity mask intersects with
239 * a housekeeping CPU. If so, then remove the isolated CPUs from
240 * the mask and just keep the housekeeping CPU(s). This prevents
241 * the affinity setter from routing the interrupt to an isolated
242 * CPU to avoid that I/O submitted from a housekeeping CPU causes
243 * interrupts on an isolated one.
245 * If the masks do not intersect or include online CPU(s) then
246 * keep the requested mask. The isolated target CPUs are only
247 * receiving interrupts when the I/O operation was submitted
248 * directly from them.
250 * If all housekeeping CPUs in the affinity mask are offline, the
251 * interrupt will be migrated by the CPU hotplug code once a
252 * housekeeping CPU which belongs to the affinity mask comes
255 if (irqd_affinity_is_managed(data) &&
256 housekeeping_enabled(HK_TYPE_MANAGED_IRQ)) {
257 const struct cpumask *hk_mask;
259 hk_mask = housekeeping_cpumask(HK_TYPE_MANAGED_IRQ);
261 cpumask_and(&tmp_mask, mask, hk_mask);
262 if (!cpumask_intersects(&tmp_mask, cpu_online_mask))
265 prog_mask = &tmp_mask;
271 * Make sure we only provide online CPUs to the irqchip,
272 * unless we are being asked to force the affinity (in which
273 * case we do as we are told).
275 cpumask_and(&tmp_mask, prog_mask, cpu_online_mask);
276 if (!force && !cpumask_empty(&tmp_mask))
277 ret = chip->irq_set_affinity(data, &tmp_mask, force);
279 ret = chip->irq_set_affinity(data, mask, force);
283 raw_spin_unlock(&tmp_mask_lock);
286 case IRQ_SET_MASK_OK:
287 case IRQ_SET_MASK_OK_DONE:
288 cpumask_copy(desc->irq_common_data.affinity, mask);
290 case IRQ_SET_MASK_OK_NOCOPY:
291 irq_validate_effective_affinity(data);
292 irq_set_thread_affinity(desc);
299 #ifdef CONFIG_GENERIC_PENDING_IRQ
300 static inline int irq_set_affinity_pending(struct irq_data *data,
301 const struct cpumask *dest)
303 struct irq_desc *desc = irq_data_to_desc(data);
305 irqd_set_move_pending(data);
306 irq_copy_pending(desc, dest);
310 static inline int irq_set_affinity_pending(struct irq_data *data,
311 const struct cpumask *dest)
317 static int irq_try_set_affinity(struct irq_data *data,
318 const struct cpumask *dest, bool force)
320 int ret = irq_do_set_affinity(data, dest, force);
323 * In case that the underlying vector management is busy and the
324 * architecture supports the generic pending mechanism then utilize
325 * this to avoid returning an error to user space.
327 if (ret == -EBUSY && !force)
328 ret = irq_set_affinity_pending(data, dest);
332 static bool irq_set_affinity_deactivated(struct irq_data *data,
333 const struct cpumask *mask)
335 struct irq_desc *desc = irq_data_to_desc(data);
338 * Handle irq chips which can handle affinity only in activated
341 * If the interrupt is not yet activated, just store the affinity
342 * mask and do not call the chip driver at all. On activation the
343 * driver has to make sure anyway that the interrupt is in a
344 * usable state so startup works.
346 if (!IS_ENABLED(CONFIG_IRQ_DOMAIN_HIERARCHY) ||
347 irqd_is_activated(data) || !irqd_affinity_on_activate(data))
350 cpumask_copy(desc->irq_common_data.affinity, mask);
351 irq_data_update_effective_affinity(data, mask);
352 irqd_set(data, IRQD_AFFINITY_SET);
356 int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
359 struct irq_chip *chip = irq_data_get_irq_chip(data);
360 struct irq_desc *desc = irq_data_to_desc(data);
363 if (!chip || !chip->irq_set_affinity)
366 if (irq_set_affinity_deactivated(data, mask))
369 if (irq_can_move_pcntxt(data) && !irqd_is_setaffinity_pending(data)) {
370 ret = irq_try_set_affinity(data, mask, force);
372 irqd_set_move_pending(data);
373 irq_copy_pending(desc, mask);
376 if (desc->affinity_notify) {
377 kref_get(&desc->affinity_notify->kref);
378 if (!schedule_work(&desc->affinity_notify->work)) {
379 /* Work was already scheduled, drop our extra ref */
380 kref_put(&desc->affinity_notify->kref,
381 desc->affinity_notify->release);
384 irqd_set(data, IRQD_AFFINITY_SET);
390 * irq_update_affinity_desc - Update affinity management for an interrupt
391 * @irq: The interrupt number to update
392 * @affinity: Pointer to the affinity descriptor
394 * This interface can be used to configure the affinity management of
395 * interrupts which have been allocated already.
397 * There are certain limitations on when it may be used - attempts to use it
398 * for when the kernel is configured for generic IRQ reservation mode (in
399 * config GENERIC_IRQ_RESERVATION_MODE) will fail, as it may conflict with
400 * managed/non-managed interrupt accounting. In addition, attempts to use it on
401 * an interrupt which is already started or which has already been configured
402 * as managed will also fail, as these mean invalid init state or double init.
404 int irq_update_affinity_desc(unsigned int irq,
405 struct irq_affinity_desc *affinity)
407 struct irq_desc *desc;
413 * Supporting this with the reservation scheme used by x86 needs
414 * some more thought. Fail it for now.
416 if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE))
419 desc = irq_get_desc_buslock(irq, &flags, 0);
423 /* Requires the interrupt to be shut down */
424 if (irqd_is_started(&desc->irq_data)) {
429 /* Interrupts which are already managed cannot be modified */
430 if (irqd_affinity_is_managed(&desc->irq_data)) {
436 * Deactivate the interrupt. That's required to undo
437 * anything an earlier activation has established.
439 activated = irqd_is_activated(&desc->irq_data);
441 irq_domain_deactivate_irq(&desc->irq_data);
443 if (affinity->is_managed) {
444 irqd_set(&desc->irq_data, IRQD_AFFINITY_MANAGED);
445 irqd_set(&desc->irq_data, IRQD_MANAGED_SHUTDOWN);
448 cpumask_copy(desc->irq_common_data.affinity, &affinity->mask);
450 /* Restore the activation state */
452 irq_domain_activate_irq(&desc->irq_data, false);
455 irq_put_desc_busunlock(desc, flags);
459 static int __irq_set_affinity(unsigned int irq, const struct cpumask *mask,
462 struct irq_desc *desc = irq_to_desc(irq);
469 raw_spin_lock_irqsave(&desc->lock, flags);
470 ret = irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask, force);
471 raw_spin_unlock_irqrestore(&desc->lock, flags);
476 * irq_set_affinity - Set the irq affinity of a given irq
477 * @irq: Interrupt to set affinity
480 * Fails if cpumask does not contain an online CPU
482 int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
484 return __irq_set_affinity(irq, cpumask, false);
486 EXPORT_SYMBOL_GPL(irq_set_affinity);
489 * irq_force_affinity - Force the irq affinity of a given irq
490 * @irq: Interrupt to set affinity
493 * Same as irq_set_affinity, but without checking the mask against
496 * Solely for low level cpu hotplug code, where we need to make per
497 * cpu interrupts affine before the cpu becomes online.
499 int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
501 return __irq_set_affinity(irq, cpumask, true);
503 EXPORT_SYMBOL_GPL(irq_force_affinity);
505 int __irq_apply_affinity_hint(unsigned int irq, const struct cpumask *m,
509 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
513 desc->affinity_hint = m;
514 irq_put_desc_unlock(desc, flags);
515 if (m && setaffinity)
516 __irq_set_affinity(irq, m, false);
519 EXPORT_SYMBOL_GPL(__irq_apply_affinity_hint);
521 static void irq_affinity_notify(struct work_struct *work)
523 struct irq_affinity_notify *notify =
524 container_of(work, struct irq_affinity_notify, work);
525 struct irq_desc *desc = irq_to_desc(notify->irq);
526 cpumask_var_t cpumask;
529 if (!desc || !alloc_cpumask_var(&cpumask, GFP_KERNEL))
532 raw_spin_lock_irqsave(&desc->lock, flags);
533 if (irq_move_pending(&desc->irq_data))
534 irq_get_pending(cpumask, desc);
536 cpumask_copy(cpumask, desc->irq_common_data.affinity);
537 raw_spin_unlock_irqrestore(&desc->lock, flags);
539 notify->notify(notify, cpumask);
541 free_cpumask_var(cpumask);
543 kref_put(¬ify->kref, notify->release);
547 * irq_set_affinity_notifier - control notification of IRQ affinity changes
548 * @irq: Interrupt for which to enable/disable notification
549 * @notify: Context for notification, or %NULL to disable
550 * notification. Function pointers must be initialised;
551 * the other fields will be initialised by this function.
553 * Must be called in process context. Notification may only be enabled
554 * after the IRQ is allocated and must be disabled before the IRQ is
555 * freed using free_irq().
558 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
560 struct irq_desc *desc = irq_to_desc(irq);
561 struct irq_affinity_notify *old_notify;
564 /* The release function is promised process context */
567 if (!desc || irq_is_nmi(desc))
570 /* Complete initialisation of *notify */
573 kref_init(¬ify->kref);
574 INIT_WORK(¬ify->work, irq_affinity_notify);
577 raw_spin_lock_irqsave(&desc->lock, flags);
578 old_notify = desc->affinity_notify;
579 desc->affinity_notify = notify;
580 raw_spin_unlock_irqrestore(&desc->lock, flags);
583 if (cancel_work_sync(&old_notify->work)) {
584 /* Pending work had a ref, put that one too */
585 kref_put(&old_notify->kref, old_notify->release);
587 kref_put(&old_notify->kref, old_notify->release);
592 EXPORT_SYMBOL_GPL(irq_set_affinity_notifier);
594 #ifndef CONFIG_AUTO_IRQ_AFFINITY
596 * Generic version of the affinity autoselector.
598 int irq_setup_affinity(struct irq_desc *desc)
600 struct cpumask *set = irq_default_affinity;
601 int ret, node = irq_desc_get_node(desc);
602 static DEFINE_RAW_SPINLOCK(mask_lock);
603 static struct cpumask mask;
605 /* Excludes PER_CPU and NO_BALANCE interrupts */
606 if (!__irq_can_set_affinity(desc))
609 raw_spin_lock(&mask_lock);
611 * Preserve the managed affinity setting and a userspace affinity
612 * setup, but make sure that one of the targets is online.
614 if (irqd_affinity_is_managed(&desc->irq_data) ||
615 irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) {
616 if (cpumask_intersects(desc->irq_common_data.affinity,
618 set = desc->irq_common_data.affinity;
620 irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET);
623 cpumask_and(&mask, cpu_online_mask, set);
624 if (cpumask_empty(&mask))
625 cpumask_copy(&mask, cpu_online_mask);
627 if (node != NUMA_NO_NODE) {
628 const struct cpumask *nodemask = cpumask_of_node(node);
630 /* make sure at least one of the cpus in nodemask is online */
631 if (cpumask_intersects(&mask, nodemask))
632 cpumask_and(&mask, &mask, nodemask);
634 ret = irq_do_set_affinity(&desc->irq_data, &mask, false);
635 raw_spin_unlock(&mask_lock);
639 /* Wrapper for ALPHA specific affinity selector magic */
640 int irq_setup_affinity(struct irq_desc *desc)
642 return irq_select_affinity(irq_desc_get_irq(desc));
644 #endif /* CONFIG_AUTO_IRQ_AFFINITY */
645 #endif /* CONFIG_SMP */
649 * irq_set_vcpu_affinity - Set vcpu affinity for the interrupt
650 * @irq: interrupt number to set affinity
651 * @vcpu_info: vCPU specific data or pointer to a percpu array of vCPU
652 * specific data for percpu_devid interrupts
654 * This function uses the vCPU specific data to set the vCPU
655 * affinity for an irq. The vCPU specific data is passed from
656 * outside, such as KVM. One example code path is as below:
657 * KVM -> IOMMU -> irq_set_vcpu_affinity().
659 int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info)
662 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
663 struct irq_data *data;
664 struct irq_chip *chip;
670 data = irq_desc_get_irq_data(desc);
672 chip = irq_data_get_irq_chip(data);
673 if (chip && chip->irq_set_vcpu_affinity)
675 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
676 data = data->parent_data;
683 ret = chip->irq_set_vcpu_affinity(data, vcpu_info);
684 irq_put_desc_unlock(desc, flags);
688 EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity);
690 void __disable_irq(struct irq_desc *desc)
696 static int __disable_irq_nosync(unsigned int irq)
699 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
704 irq_put_desc_busunlock(desc, flags);
709 * disable_irq_nosync - disable an irq without waiting
710 * @irq: Interrupt to disable
712 * Disable the selected interrupt line. Disables and Enables are
714 * Unlike disable_irq(), this function does not ensure existing
715 * instances of the IRQ handler have completed before returning.
717 * This function may be called from IRQ context.
719 void disable_irq_nosync(unsigned int irq)
721 __disable_irq_nosync(irq);
723 EXPORT_SYMBOL(disable_irq_nosync);
726 * disable_irq - disable an irq and wait for completion
727 * @irq: Interrupt to disable
729 * Disable the selected interrupt line. Enables and Disables are
731 * This function waits for any pending IRQ handlers for this interrupt
732 * to complete before returning. If you use this function while
733 * holding a resource the IRQ handler may need you will deadlock.
735 * Can only be called from preemptible code as it might sleep when
736 * an interrupt thread is associated to @irq.
739 void disable_irq(unsigned int irq)
742 if (!__disable_irq_nosync(irq))
743 synchronize_irq(irq);
745 EXPORT_SYMBOL(disable_irq);
748 * disable_hardirq - disables an irq and waits for hardirq completion
749 * @irq: Interrupt to disable
751 * Disable the selected interrupt line. Enables and Disables are
753 * This function waits for any pending hard IRQ handlers for this
754 * interrupt to complete before returning. If you use this function while
755 * holding a resource the hard IRQ handler may need you will deadlock.
757 * When used to optimistically disable an interrupt from atomic context
758 * the return value must be checked.
760 * Returns: false if a threaded handler is active.
762 * This function may be called - with care - from IRQ context.
764 bool disable_hardirq(unsigned int irq)
766 if (!__disable_irq_nosync(irq))
767 return synchronize_hardirq(irq);
771 EXPORT_SYMBOL_GPL(disable_hardirq);
774 * disable_nmi_nosync - disable an nmi without waiting
775 * @irq: Interrupt to disable
777 * Disable the selected interrupt line. Disables and enables are
779 * The interrupt to disable must have been requested through request_nmi.
780 * Unlike disable_nmi(), this function does not ensure existing
781 * instances of the IRQ handler have completed before returning.
783 void disable_nmi_nosync(unsigned int irq)
785 disable_irq_nosync(irq);
788 void __enable_irq(struct irq_desc *desc)
790 switch (desc->depth) {
793 WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n",
794 irq_desc_get_irq(desc));
797 if (desc->istate & IRQS_SUSPENDED)
799 /* Prevent probing on this irq: */
800 irq_settings_set_noprobe(desc);
802 * Call irq_startup() not irq_enable() here because the
803 * interrupt might be marked NOAUTOEN so irq_startup()
804 * needs to be invoked when it gets enabled the first time.
805 * This is also required when __enable_irq() is invoked for
806 * a managed and shutdown interrupt from the S3 resume
809 * If it was already started up, then irq_startup() will
810 * invoke irq_enable() under the hood.
812 irq_startup(desc, IRQ_RESEND, IRQ_START_FORCE);
821 * enable_irq - enable handling of an irq
822 * @irq: Interrupt to enable
824 * Undoes the effect of one call to disable_irq(). If this
825 * matches the last disable, processing of interrupts on this
826 * IRQ line is re-enabled.
828 * This function may be called from IRQ context only when
829 * desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
831 void enable_irq(unsigned int irq)
834 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
838 if (WARN(!desc->irq_data.chip,
839 KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
844 irq_put_desc_busunlock(desc, flags);
846 EXPORT_SYMBOL(enable_irq);
849 * enable_nmi - enable handling of an nmi
850 * @irq: Interrupt to enable
852 * The interrupt to enable must have been requested through request_nmi.
853 * Undoes the effect of one call to disable_nmi(). If this
854 * matches the last disable, processing of interrupts on this
855 * IRQ line is re-enabled.
857 void enable_nmi(unsigned int irq)
862 static int set_irq_wake_real(unsigned int irq, unsigned int on)
864 struct irq_desc *desc = irq_to_desc(irq);
867 if (irq_desc_get_chip(desc)->flags & IRQCHIP_SKIP_SET_WAKE)
870 if (desc->irq_data.chip->irq_set_wake)
871 ret = desc->irq_data.chip->irq_set_wake(&desc->irq_data, on);
877 * irq_set_irq_wake - control irq power management wakeup
878 * @irq: interrupt to control
879 * @on: enable/disable power management wakeup
881 * Enable/disable power management wakeup mode, which is
882 * disabled by default. Enables and disables must match,
883 * just as they match for non-wakeup mode support.
885 * Wakeup mode lets this IRQ wake the system from sleep
886 * states like "suspend to RAM".
888 * Note: irq enable/disable state is completely orthogonal
889 * to the enable/disable state of irq wake. An irq can be
890 * disabled with disable_irq() and still wake the system as
891 * long as the irq has wake enabled. If this does not hold,
892 * then the underlying irq chip and the related driver need
893 * to be investigated.
895 int irq_set_irq_wake(unsigned int irq, unsigned int on)
898 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
904 /* Don't use NMIs as wake up interrupts please */
905 if (irq_is_nmi(desc)) {
910 /* wakeup-capable irqs can be shared between drivers that
911 * don't need to have the same sleep mode behaviors.
914 if (desc->wake_depth++ == 0) {
915 ret = set_irq_wake_real(irq, on);
917 desc->wake_depth = 0;
919 irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE);
922 if (desc->wake_depth == 0) {
923 WARN(1, "Unbalanced IRQ %d wake disable\n", irq);
924 } else if (--desc->wake_depth == 0) {
925 ret = set_irq_wake_real(irq, on);
927 desc->wake_depth = 1;
929 irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
934 irq_put_desc_busunlock(desc, flags);
937 EXPORT_SYMBOL(irq_set_irq_wake);
940 * Internal function that tells the architecture code whether a
941 * particular irq has been exclusively allocated or is available
944 int can_request_irq(unsigned int irq, unsigned long irqflags)
947 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
953 if (irq_settings_can_request(desc)) {
955 irqflags & desc->action->flags & IRQF_SHARED)
958 irq_put_desc_unlock(desc, flags);
962 int __irq_set_trigger(struct irq_desc *desc, unsigned long flags)
964 struct irq_chip *chip = desc->irq_data.chip;
967 if (!chip || !chip->irq_set_type) {
969 * IRQF_TRIGGER_* but the PIC does not support multiple
972 pr_debug("No set_type function for IRQ %d (%s)\n",
973 irq_desc_get_irq(desc),
974 chip ? (chip->name ? : "unknown") : "unknown");
978 if (chip->flags & IRQCHIP_SET_TYPE_MASKED) {
979 if (!irqd_irq_masked(&desc->irq_data))
981 if (!irqd_irq_disabled(&desc->irq_data))
985 /* Mask all flags except trigger mode */
986 flags &= IRQ_TYPE_SENSE_MASK;
987 ret = chip->irq_set_type(&desc->irq_data, flags);
990 case IRQ_SET_MASK_OK:
991 case IRQ_SET_MASK_OK_DONE:
992 irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK);
993 irqd_set(&desc->irq_data, flags);
996 case IRQ_SET_MASK_OK_NOCOPY:
997 flags = irqd_get_trigger_type(&desc->irq_data);
998 irq_settings_set_trigger_mask(desc, flags);
999 irqd_clear(&desc->irq_data, IRQD_LEVEL);
1000 irq_settings_clr_level(desc);
1001 if (flags & IRQ_TYPE_LEVEL_MASK) {
1002 irq_settings_set_level(desc);
1003 irqd_set(&desc->irq_data, IRQD_LEVEL);
1009 pr_err("Setting trigger mode %lu for irq %u failed (%pS)\n",
1010 flags, irq_desc_get_irq(desc), chip->irq_set_type);
1017 #ifdef CONFIG_HARDIRQS_SW_RESEND
1018 int irq_set_parent(int irq, int parent_irq)
1020 unsigned long flags;
1021 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
1026 desc->parent_irq = parent_irq;
1028 irq_put_desc_unlock(desc, flags);
1031 EXPORT_SYMBOL_GPL(irq_set_parent);
1035 * Default primary interrupt handler for threaded interrupts. Is
1036 * assigned as primary handler when request_threaded_irq is called
1037 * with handler == NULL. Useful for oneshot interrupts.
1039 static irqreturn_t irq_default_primary_handler(int irq, void *dev_id)
1041 return IRQ_WAKE_THREAD;
1045 * Primary handler for nested threaded interrupts. Should never be
1048 static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)
1050 WARN(1, "Primary handler called for nested irq %d\n", irq);
1054 static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id)
1056 WARN(1, "Secondary action handler called for irq %d\n", irq);
1062 * Check whether we need to change the affinity of the interrupt thread.
1064 static void irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
1069 if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags))
1072 __set_current_state(TASK_RUNNING);
1075 * In case we are out of memory we set IRQTF_AFFINITY again and
1076 * try again next time
1078 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {
1079 set_bit(IRQTF_AFFINITY, &action->thread_flags);
1083 raw_spin_lock_irq(&desc->lock);
1085 * This code is triggered unconditionally. Check the affinity
1086 * mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
1088 if (cpumask_available(desc->irq_common_data.affinity)) {
1089 const struct cpumask *m;
1091 m = irq_data_get_effective_affinity_mask(&desc->irq_data);
1092 cpumask_copy(mask, m);
1095 raw_spin_unlock_irq(&desc->lock);
1098 set_cpus_allowed_ptr(current, mask);
1099 free_cpumask_var(mask);
1102 static inline void irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { }
1105 static int irq_wait_for_interrupt(struct irq_desc *desc,
1106 struct irqaction *action)
1109 set_current_state(TASK_INTERRUPTIBLE);
1110 irq_thread_check_affinity(desc, action);
1112 if (kthread_should_stop()) {
1113 /* may need to run one last time */
1114 if (test_and_clear_bit(IRQTF_RUNTHREAD,
1115 &action->thread_flags)) {
1116 __set_current_state(TASK_RUNNING);
1119 __set_current_state(TASK_RUNNING);
1123 if (test_and_clear_bit(IRQTF_RUNTHREAD,
1124 &action->thread_flags)) {
1125 __set_current_state(TASK_RUNNING);
1133 * Oneshot interrupts keep the irq line masked until the threaded
1134 * handler finished. unmask if the interrupt has not been disabled and
1137 static void irq_finalize_oneshot(struct irq_desc *desc,
1138 struct irqaction *action)
1140 if (!(desc->istate & IRQS_ONESHOT) ||
1141 action->handler == irq_forced_secondary_handler)
1144 chip_bus_lock(desc);
1145 raw_spin_lock_irq(&desc->lock);
1148 * Implausible though it may be we need to protect us against
1149 * the following scenario:
1151 * The thread is faster done than the hard interrupt handler
1152 * on the other CPU. If we unmask the irq line then the
1153 * interrupt can come in again and masks the line, leaves due
1154 * to IRQS_INPROGRESS and the irq line is masked forever.
1156 * This also serializes the state of shared oneshot handlers
1157 * versus "desc->threads_oneshot |= action->thread_mask;" in
1158 * irq_wake_thread(). See the comment there which explains the
1161 if (unlikely(irqd_irq_inprogress(&desc->irq_data))) {
1162 raw_spin_unlock_irq(&desc->lock);
1163 chip_bus_sync_unlock(desc);
1169 * Now check again, whether the thread should run. Otherwise
1170 * we would clear the threads_oneshot bit of this thread which
1173 if (test_bit(IRQTF_RUNTHREAD, &action->thread_flags))
1176 desc->threads_oneshot &= ~action->thread_mask;
1178 if (!desc->threads_oneshot && !irqd_irq_disabled(&desc->irq_data) &&
1179 irqd_irq_masked(&desc->irq_data))
1180 unmask_threaded_irq(desc);
1183 raw_spin_unlock_irq(&desc->lock);
1184 chip_bus_sync_unlock(desc);
1188 * Interrupts which are not explicitly requested as threaded
1189 * interrupts rely on the implicit bh/preempt disable of the hard irq
1190 * context. So we need to disable bh here to avoid deadlocks and other
1194 irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
1199 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
1200 local_irq_disable();
1201 ret = action->thread_fn(action->irq, action->dev_id);
1202 if (ret == IRQ_HANDLED)
1203 atomic_inc(&desc->threads_handled);
1205 irq_finalize_oneshot(desc, action);
1206 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
1213 * Interrupts explicitly requested as threaded interrupts want to be
1214 * preemptible - many of them need to sleep and wait for slow busses to
1217 static irqreturn_t irq_thread_fn(struct irq_desc *desc,
1218 struct irqaction *action)
1222 ret = action->thread_fn(action->irq, action->dev_id);
1223 if (ret == IRQ_HANDLED)
1224 atomic_inc(&desc->threads_handled);
1226 irq_finalize_oneshot(desc, action);
1230 void wake_threads_waitq(struct irq_desc *desc)
1232 if (atomic_dec_and_test(&desc->threads_active))
1233 wake_up(&desc->wait_for_threads);
1236 static void irq_thread_dtor(struct callback_head *unused)
1238 struct task_struct *tsk = current;
1239 struct irq_desc *desc;
1240 struct irqaction *action;
1242 if (WARN_ON_ONCE(!(current->flags & PF_EXITING)))
1245 action = kthread_data(tsk);
1247 pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
1248 tsk->comm, tsk->pid, action->irq);
1251 desc = irq_to_desc(action->irq);
1253 * If IRQTF_RUNTHREAD is set, we need to decrement
1254 * desc->threads_active and wake possible waiters.
1256 if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
1257 wake_threads_waitq(desc);
1259 /* Prevent a stale desc->threads_oneshot */
1260 irq_finalize_oneshot(desc, action);
1263 static void irq_wake_secondary(struct irq_desc *desc, struct irqaction *action)
1265 struct irqaction *secondary = action->secondary;
1267 if (WARN_ON_ONCE(!secondary))
1270 raw_spin_lock_irq(&desc->lock);
1271 __irq_wake_thread(desc, secondary);
1272 raw_spin_unlock_irq(&desc->lock);
1276 * Internal function to notify that a interrupt thread is ready.
1278 static void irq_thread_set_ready(struct irq_desc *desc,
1279 struct irqaction *action)
1281 set_bit(IRQTF_READY, &action->thread_flags);
1282 wake_up(&desc->wait_for_threads);
1286 * Internal function to wake up a interrupt thread and wait until it is
1289 static void wake_up_and_wait_for_irq_thread_ready(struct irq_desc *desc,
1290 struct irqaction *action)
1292 if (!action || !action->thread)
1295 wake_up_process(action->thread);
1296 wait_event(desc->wait_for_threads,
1297 test_bit(IRQTF_READY, &action->thread_flags));
1301 * Interrupt handler thread
1303 static int irq_thread(void *data)
1305 struct callback_head on_exit_work;
1306 struct irqaction *action = data;
1307 struct irq_desc *desc = irq_to_desc(action->irq);
1308 irqreturn_t (*handler_fn)(struct irq_desc *desc,
1309 struct irqaction *action);
1311 irq_thread_set_ready(desc, action);
1313 sched_set_fifo(current);
1315 if (force_irqthreads() && test_bit(IRQTF_FORCED_THREAD,
1316 &action->thread_flags))
1317 handler_fn = irq_forced_thread_fn;
1319 handler_fn = irq_thread_fn;
1321 init_task_work(&on_exit_work, irq_thread_dtor);
1322 task_work_add(current, &on_exit_work, TWA_NONE);
1324 while (!irq_wait_for_interrupt(desc, action)) {
1325 irqreturn_t action_ret;
1327 action_ret = handler_fn(desc, action);
1328 if (action_ret == IRQ_WAKE_THREAD)
1329 irq_wake_secondary(desc, action);
1331 wake_threads_waitq(desc);
1335 * This is the regular exit path. __free_irq() is stopping the
1336 * thread via kthread_stop() after calling
1337 * synchronize_hardirq(). So neither IRQTF_RUNTHREAD nor the
1338 * oneshot mask bit can be set.
1340 task_work_cancel(current, irq_thread_dtor);
1345 * irq_wake_thread - wake the irq thread for the action identified by dev_id
1346 * @irq: Interrupt line
1347 * @dev_id: Device identity for which the thread should be woken
1350 void irq_wake_thread(unsigned int irq, void *dev_id)
1352 struct irq_desc *desc = irq_to_desc(irq);
1353 struct irqaction *action;
1354 unsigned long flags;
1356 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1359 raw_spin_lock_irqsave(&desc->lock, flags);
1360 for_each_action_of_desc(desc, action) {
1361 if (action->dev_id == dev_id) {
1363 __irq_wake_thread(desc, action);
1367 raw_spin_unlock_irqrestore(&desc->lock, flags);
1369 EXPORT_SYMBOL_GPL(irq_wake_thread);
1371 static int irq_setup_forced_threading(struct irqaction *new)
1373 if (!force_irqthreads())
1375 if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))
1379 * No further action required for interrupts which are requested as
1380 * threaded interrupts already
1382 if (new->handler == irq_default_primary_handler)
1385 new->flags |= IRQF_ONESHOT;
1388 * Handle the case where we have a real primary handler and a
1389 * thread handler. We force thread them as well by creating a
1392 if (new->handler && new->thread_fn) {
1393 /* Allocate the secondary action */
1394 new->secondary = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
1395 if (!new->secondary)
1397 new->secondary->handler = irq_forced_secondary_handler;
1398 new->secondary->thread_fn = new->thread_fn;
1399 new->secondary->dev_id = new->dev_id;
1400 new->secondary->irq = new->irq;
1401 new->secondary->name = new->name;
1403 /* Deal with the primary handler */
1404 set_bit(IRQTF_FORCED_THREAD, &new->thread_flags);
1405 new->thread_fn = new->handler;
1406 new->handler = irq_default_primary_handler;
1410 static int irq_request_resources(struct irq_desc *desc)
1412 struct irq_data *d = &desc->irq_data;
1413 struct irq_chip *c = d->chip;
1415 return c->irq_request_resources ? c->irq_request_resources(d) : 0;
1418 static void irq_release_resources(struct irq_desc *desc)
1420 struct irq_data *d = &desc->irq_data;
1421 struct irq_chip *c = d->chip;
1423 if (c->irq_release_resources)
1424 c->irq_release_resources(d);
1427 static bool irq_supports_nmi(struct irq_desc *desc)
1429 struct irq_data *d = irq_desc_get_irq_data(desc);
1431 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1432 /* Only IRQs directly managed by the root irqchip can be set as NMI */
1436 /* Don't support NMIs for chips behind a slow bus */
1437 if (d->chip->irq_bus_lock || d->chip->irq_bus_sync_unlock)
1440 return d->chip->flags & IRQCHIP_SUPPORTS_NMI;
1443 static int irq_nmi_setup(struct irq_desc *desc)
1445 struct irq_data *d = irq_desc_get_irq_data(desc);
1446 struct irq_chip *c = d->chip;
1448 return c->irq_nmi_setup ? c->irq_nmi_setup(d) : -EINVAL;
1451 static void irq_nmi_teardown(struct irq_desc *desc)
1453 struct irq_data *d = irq_desc_get_irq_data(desc);
1454 struct irq_chip *c = d->chip;
1456 if (c->irq_nmi_teardown)
1457 c->irq_nmi_teardown(d);
1461 setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
1463 struct task_struct *t;
1466 t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
1469 t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq,
1477 * We keep the reference to the task struct even if
1478 * the thread dies to avoid that the interrupt code
1479 * references an already freed task_struct.
1481 new->thread = get_task_struct(t);
1483 * Tell the thread to set its affinity. This is
1484 * important for shared interrupt handlers as we do
1485 * not invoke setup_affinity() for the secondary
1486 * handlers as everything is already set up. Even for
1487 * interrupts marked with IRQF_NO_BALANCE this is
1488 * correct as we want the thread to move to the cpu(s)
1489 * on which the requesting code placed the interrupt.
1491 set_bit(IRQTF_AFFINITY, &new->thread_flags);
1496 * Internal function to register an irqaction - typically used to
1497 * allocate special interrupts that are part of the architecture.
1501 * desc->request_mutex Provides serialization against a concurrent free_irq()
1502 * chip_bus_lock Provides serialization for slow bus operations
1503 * desc->lock Provides serialization against hard interrupts
1505 * chip_bus_lock and desc->lock are sufficient for all other management and
1506 * interrupt related functions. desc->request_mutex solely serializes
1507 * request/free_irq().
1510 __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
1512 struct irqaction *old, **old_ptr;
1513 unsigned long flags, thread_mask = 0;
1514 int ret, nested, shared = 0;
1519 if (desc->irq_data.chip == &no_irq_chip)
1521 if (!try_module_get(desc->owner))
1527 * If the trigger type is not specified by the caller,
1528 * then use the default for this interrupt.
1530 if (!(new->flags & IRQF_TRIGGER_MASK))
1531 new->flags |= irqd_get_trigger_type(&desc->irq_data);
1534 * Check whether the interrupt nests into another interrupt
1537 nested = irq_settings_is_nested_thread(desc);
1539 if (!new->thread_fn) {
1544 * Replace the primary handler which was provided from
1545 * the driver for non nested interrupt handling by the
1546 * dummy function which warns when called.
1548 new->handler = irq_nested_primary_handler;
1550 if (irq_settings_can_thread(desc)) {
1551 ret = irq_setup_forced_threading(new);
1558 * Create a handler thread when a thread function is supplied
1559 * and the interrupt does not nest into another interrupt
1562 if (new->thread_fn && !nested) {
1563 ret = setup_irq_thread(new, irq, false);
1566 if (new->secondary) {
1567 ret = setup_irq_thread(new->secondary, irq, true);
1574 * Drivers are often written to work w/o knowledge about the
1575 * underlying irq chip implementation, so a request for a
1576 * threaded irq without a primary hard irq context handler
1577 * requires the ONESHOT flag to be set. Some irq chips like
1578 * MSI based interrupts are per se one shot safe. Check the
1579 * chip flags, so we can avoid the unmask dance at the end of
1580 * the threaded handler for those.
1582 if (desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)
1583 new->flags &= ~IRQF_ONESHOT;
1586 * Protects against a concurrent __free_irq() call which might wait
1587 * for synchronize_hardirq() to complete without holding the optional
1588 * chip bus lock and desc->lock. Also protects against handing out
1589 * a recycled oneshot thread_mask bit while it's still in use by
1590 * its previous owner.
1592 mutex_lock(&desc->request_mutex);
1595 * Acquire bus lock as the irq_request_resources() callback below
1596 * might rely on the serialization or the magic power management
1597 * functions which are abusing the irq_bus_lock() callback,
1599 chip_bus_lock(desc);
1601 /* First installed action requests resources. */
1602 if (!desc->action) {
1603 ret = irq_request_resources(desc);
1605 pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
1606 new->name, irq, desc->irq_data.chip->name);
1607 goto out_bus_unlock;
1612 * The following block of code has to be executed atomically
1613 * protected against a concurrent interrupt and any of the other
1614 * management calls which are not serialized via
1615 * desc->request_mutex or the optional bus lock.
1617 raw_spin_lock_irqsave(&desc->lock, flags);
1618 old_ptr = &desc->action;
1622 * Can't share interrupts unless both agree to and are
1623 * the same type (level, edge, polarity). So both flag
1624 * fields must have IRQF_SHARED set and the bits which
1625 * set the trigger type must match. Also all must
1627 * Interrupt lines used for NMIs cannot be shared.
1629 unsigned int oldtype;
1631 if (irq_is_nmi(desc)) {
1632 pr_err("Invalid attempt to share NMI for %s (irq %d) on irqchip %s.\n",
1633 new->name, irq, desc->irq_data.chip->name);
1639 * If nobody did set the configuration before, inherit
1640 * the one provided by the requester.
1642 if (irqd_trigger_type_was_set(&desc->irq_data)) {
1643 oldtype = irqd_get_trigger_type(&desc->irq_data);
1645 oldtype = new->flags & IRQF_TRIGGER_MASK;
1646 irqd_set_trigger_type(&desc->irq_data, oldtype);
1649 if (!((old->flags & new->flags) & IRQF_SHARED) ||
1650 (oldtype != (new->flags & IRQF_TRIGGER_MASK)))
1653 if ((old->flags & IRQF_ONESHOT) &&
1654 (new->flags & IRQF_COND_ONESHOT))
1655 new->flags |= IRQF_ONESHOT;
1656 else if ((old->flags ^ new->flags) & IRQF_ONESHOT)
1659 /* All handlers must agree on per-cpuness */
1660 if ((old->flags & IRQF_PERCPU) !=
1661 (new->flags & IRQF_PERCPU))
1664 /* add new interrupt at end of irq queue */
1667 * Or all existing action->thread_mask bits,
1668 * so we can find the next zero bit for this
1671 thread_mask |= old->thread_mask;
1672 old_ptr = &old->next;
1679 * Setup the thread mask for this irqaction for ONESHOT. For
1680 * !ONESHOT irqs the thread mask is 0 so we can avoid a
1681 * conditional in irq_wake_thread().
1683 if (new->flags & IRQF_ONESHOT) {
1685 * Unlikely to have 32 resp 64 irqs sharing one line,
1688 if (thread_mask == ~0UL) {
1693 * The thread_mask for the action is or'ed to
1694 * desc->thread_active to indicate that the
1695 * IRQF_ONESHOT thread handler has been woken, but not
1696 * yet finished. The bit is cleared when a thread
1697 * completes. When all threads of a shared interrupt
1698 * line have completed desc->threads_active becomes
1699 * zero and the interrupt line is unmasked. See
1700 * handle.c:irq_wake_thread() for further information.
1702 * If no thread is woken by primary (hard irq context)
1703 * interrupt handlers, then desc->threads_active is
1704 * also checked for zero to unmask the irq line in the
1705 * affected hard irq flow handlers
1706 * (handle_[fasteoi|level]_irq).
1708 * The new action gets the first zero bit of
1709 * thread_mask assigned. See the loop above which or's
1710 * all existing action->thread_mask bits.
1712 new->thread_mask = 1UL << ffz(thread_mask);
1714 } else if (new->handler == irq_default_primary_handler &&
1715 !(desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)) {
1717 * The interrupt was requested with handler = NULL, so
1718 * we use the default primary handler for it. But it
1719 * does not have the oneshot flag set. In combination
1720 * with level interrupts this is deadly, because the
1721 * default primary handler just wakes the thread, then
1722 * the irq lines is reenabled, but the device still
1723 * has the level irq asserted. Rinse and repeat....
1725 * While this works for edge type interrupts, we play
1726 * it safe and reject unconditionally because we can't
1727 * say for sure which type this interrupt really
1728 * has. The type flags are unreliable as the
1729 * underlying chip implementation can override them.
1731 pr_err("Threaded irq requested with handler=NULL and !ONESHOT for %s (irq %d)\n",
1738 /* Setup the type (level, edge polarity) if configured: */
1739 if (new->flags & IRQF_TRIGGER_MASK) {
1740 ret = __irq_set_trigger(desc,
1741 new->flags & IRQF_TRIGGER_MASK);
1748 * Activate the interrupt. That activation must happen
1749 * independently of IRQ_NOAUTOEN. request_irq() can fail
1750 * and the callers are supposed to handle
1751 * that. enable_irq() of an interrupt requested with
1752 * IRQ_NOAUTOEN is not supposed to fail. The activation
1753 * keeps it in shutdown mode, it merily associates
1754 * resources if necessary and if that's not possible it
1755 * fails. Interrupts which are in managed shutdown mode
1756 * will simply ignore that activation request.
1758 ret = irq_activate(desc);
1762 desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \
1763 IRQS_ONESHOT | IRQS_WAITING);
1764 irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
1766 if (new->flags & IRQF_PERCPU) {
1767 irqd_set(&desc->irq_data, IRQD_PER_CPU);
1768 irq_settings_set_per_cpu(desc);
1769 if (new->flags & IRQF_NO_DEBUG)
1770 irq_settings_set_no_debug(desc);
1774 irq_settings_set_no_debug(desc);
1776 if (new->flags & IRQF_ONESHOT)
1777 desc->istate |= IRQS_ONESHOT;
1779 /* Exclude IRQ from balancing if requested */
1780 if (new->flags & IRQF_NOBALANCING) {
1781 irq_settings_set_no_balancing(desc);
1782 irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
1785 if (!(new->flags & IRQF_NO_AUTOEN) &&
1786 irq_settings_can_autoenable(desc)) {
1787 irq_startup(desc, IRQ_RESEND, IRQ_START_COND);
1790 * Shared interrupts do not go well with disabling
1791 * auto enable. The sharing interrupt might request
1792 * it while it's still disabled and then wait for
1793 * interrupts forever.
1795 WARN_ON_ONCE(new->flags & IRQF_SHARED);
1796 /* Undo nested disables: */
1800 } else if (new->flags & IRQF_TRIGGER_MASK) {
1801 unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK;
1802 unsigned int omsk = irqd_get_trigger_type(&desc->irq_data);
1805 /* hope the handler works with current trigger mode */
1806 pr_warn("irq %d uses trigger mode %u; requested %u\n",
1812 irq_pm_install_action(desc, new);
1814 /* Reset broken irq detection when installing new handler */
1815 desc->irq_count = 0;
1816 desc->irqs_unhandled = 0;
1819 * Check whether we disabled the irq via the spurious handler
1820 * before. Reenable it and give it another chance.
1822 if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) {
1823 desc->istate &= ~IRQS_SPURIOUS_DISABLED;
1827 raw_spin_unlock_irqrestore(&desc->lock, flags);
1828 chip_bus_sync_unlock(desc);
1829 mutex_unlock(&desc->request_mutex);
1831 irq_setup_timings(desc, new);
1833 wake_up_and_wait_for_irq_thread_ready(desc, new);
1834 wake_up_and_wait_for_irq_thread_ready(desc, new->secondary);
1836 register_irq_proc(irq, desc);
1838 register_handler_proc(irq, new);
1842 if (!(new->flags & IRQF_PROBE_SHARED)) {
1843 pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
1844 irq, new->flags, new->name, old->flags, old->name);
1845 #ifdef CONFIG_DEBUG_SHIRQ
1852 raw_spin_unlock_irqrestore(&desc->lock, flags);
1855 irq_release_resources(desc);
1857 chip_bus_sync_unlock(desc);
1858 mutex_unlock(&desc->request_mutex);
1862 struct task_struct *t = new->thread;
1865 kthread_stop_put(t);
1867 if (new->secondary && new->secondary->thread) {
1868 struct task_struct *t = new->secondary->thread;
1870 new->secondary->thread = NULL;
1871 kthread_stop_put(t);
1874 module_put(desc->owner);
1879 * Internal function to unregister an irqaction - used to free
1880 * regular and special interrupts that are part of the architecture.
1882 static struct irqaction *__free_irq(struct irq_desc *desc, void *dev_id)
1884 unsigned irq = desc->irq_data.irq;
1885 struct irqaction *action, **action_ptr;
1886 unsigned long flags;
1888 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
1890 mutex_lock(&desc->request_mutex);
1891 chip_bus_lock(desc);
1892 raw_spin_lock_irqsave(&desc->lock, flags);
1895 * There can be multiple actions per IRQ descriptor, find the right
1896 * one based on the dev_id:
1898 action_ptr = &desc->action;
1900 action = *action_ptr;
1903 WARN(1, "Trying to free already-free IRQ %d\n", irq);
1904 raw_spin_unlock_irqrestore(&desc->lock, flags);
1905 chip_bus_sync_unlock(desc);
1906 mutex_unlock(&desc->request_mutex);
1910 if (action->dev_id == dev_id)
1912 action_ptr = &action->next;
1915 /* Found it - now remove it from the list of entries: */
1916 *action_ptr = action->next;
1918 irq_pm_remove_action(desc, action);
1920 /* If this was the last handler, shut down the IRQ line: */
1921 if (!desc->action) {
1922 irq_settings_clr_disable_unlazy(desc);
1923 /* Only shutdown. Deactivate after synchronize_hardirq() */
1928 /* make sure affinity_hint is cleaned up */
1929 if (WARN_ON_ONCE(desc->affinity_hint))
1930 desc->affinity_hint = NULL;
1933 raw_spin_unlock_irqrestore(&desc->lock, flags);
1935 * Drop bus_lock here so the changes which were done in the chip
1936 * callbacks above are synced out to the irq chips which hang
1937 * behind a slow bus (I2C, SPI) before calling synchronize_hardirq().
1939 * Aside of that the bus_lock can also be taken from the threaded
1940 * handler in irq_finalize_oneshot() which results in a deadlock
1941 * because kthread_stop() would wait forever for the thread to
1942 * complete, which is blocked on the bus lock.
1944 * The still held desc->request_mutex() protects against a
1945 * concurrent request_irq() of this irq so the release of resources
1946 * and timing data is properly serialized.
1948 chip_bus_sync_unlock(desc);
1950 unregister_handler_proc(irq, action);
1953 * Make sure it's not being used on another CPU and if the chip
1954 * supports it also make sure that there is no (not yet serviced)
1955 * interrupt in flight at the hardware level.
1957 __synchronize_irq(desc);
1959 #ifdef CONFIG_DEBUG_SHIRQ
1961 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
1962 * event to happen even now it's being freed, so let's make sure that
1963 * is so by doing an extra call to the handler ....
1965 * ( We do this after actually deregistering it, to make sure that a
1966 * 'real' IRQ doesn't run in parallel with our fake. )
1968 if (action->flags & IRQF_SHARED) {
1969 local_irq_save(flags);
1970 action->handler(irq, dev_id);
1971 local_irq_restore(flags);
1976 * The action has already been removed above, but the thread writes
1977 * its oneshot mask bit when it completes. Though request_mutex is
1978 * held across this which prevents __setup_irq() from handing out
1979 * the same bit to a newly requested action.
1981 if (action->thread) {
1982 kthread_stop_put(action->thread);
1983 if (action->secondary && action->secondary->thread)
1984 kthread_stop_put(action->secondary->thread);
1987 /* Last action releases resources */
1988 if (!desc->action) {
1990 * Reacquire bus lock as irq_release_resources() might
1991 * require it to deallocate resources over the slow bus.
1993 chip_bus_lock(desc);
1995 * There is no interrupt on the fly anymore. Deactivate it
1998 raw_spin_lock_irqsave(&desc->lock, flags);
1999 irq_domain_deactivate_irq(&desc->irq_data);
2000 raw_spin_unlock_irqrestore(&desc->lock, flags);
2002 irq_release_resources(desc);
2003 chip_bus_sync_unlock(desc);
2004 irq_remove_timings(desc);
2007 mutex_unlock(&desc->request_mutex);
2009 irq_chip_pm_put(&desc->irq_data);
2010 module_put(desc->owner);
2011 kfree(action->secondary);
2016 * free_irq - free an interrupt allocated with request_irq
2017 * @irq: Interrupt line to free
2018 * @dev_id: Device identity to free
2020 * Remove an interrupt handler. The handler is removed and if the
2021 * interrupt line is no longer in use by any driver it is disabled.
2022 * On a shared IRQ the caller must ensure the interrupt is disabled
2023 * on the card it drives before calling this function. The function
2024 * does not return until any executing interrupts for this IRQ
2027 * This function must not be called from interrupt context.
2029 * Returns the devname argument passed to request_irq.
2031 const void *free_irq(unsigned int irq, void *dev_id)
2033 struct irq_desc *desc = irq_to_desc(irq);
2034 struct irqaction *action;
2035 const char *devname;
2037 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2041 if (WARN_ON(desc->affinity_notify))
2042 desc->affinity_notify = NULL;
2045 action = __free_irq(desc, dev_id);
2050 devname = action->name;
2054 EXPORT_SYMBOL(free_irq);
2056 /* This function must be called with desc->lock held */
2057 static const void *__cleanup_nmi(unsigned int irq, struct irq_desc *desc)
2059 const char *devname = NULL;
2061 desc->istate &= ~IRQS_NMI;
2063 if (!WARN_ON(desc->action == NULL)) {
2064 irq_pm_remove_action(desc, desc->action);
2065 devname = desc->action->name;
2066 unregister_handler_proc(irq, desc->action);
2068 kfree(desc->action);
2069 desc->action = NULL;
2072 irq_settings_clr_disable_unlazy(desc);
2073 irq_shutdown_and_deactivate(desc);
2075 irq_release_resources(desc);
2077 irq_chip_pm_put(&desc->irq_data);
2078 module_put(desc->owner);
2083 const void *free_nmi(unsigned int irq, void *dev_id)
2085 struct irq_desc *desc = irq_to_desc(irq);
2086 unsigned long flags;
2087 const void *devname;
2089 if (!desc || WARN_ON(!irq_is_nmi(desc)))
2092 if (WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2095 /* NMI still enabled */
2096 if (WARN_ON(desc->depth == 0))
2097 disable_nmi_nosync(irq);
2099 raw_spin_lock_irqsave(&desc->lock, flags);
2101 irq_nmi_teardown(desc);
2102 devname = __cleanup_nmi(irq, desc);
2104 raw_spin_unlock_irqrestore(&desc->lock, flags);
2110 * request_threaded_irq - allocate an interrupt line
2111 * @irq: Interrupt line to allocate
2112 * @handler: Function to be called when the IRQ occurs.
2113 * Primary handler for threaded interrupts.
2114 * If handler is NULL and thread_fn != NULL
2115 * the default primary handler is installed.
2116 * @thread_fn: Function called from the irq handler thread
2117 * If NULL, no irq thread is created
2118 * @irqflags: Interrupt type flags
2119 * @devname: An ascii name for the claiming device
2120 * @dev_id: A cookie passed back to the handler function
2122 * This call allocates interrupt resources and enables the
2123 * interrupt line and IRQ handling. From the point this
2124 * call is made your handler function may be invoked. Since
2125 * your handler function must clear any interrupt the board
2126 * raises, you must take care both to initialise your hardware
2127 * and to set up the interrupt handler in the right order.
2129 * If you want to set up a threaded irq handler for your device
2130 * then you need to supply @handler and @thread_fn. @handler is
2131 * still called in hard interrupt context and has to check
2132 * whether the interrupt originates from the device. If yes it
2133 * needs to disable the interrupt on the device and return
2134 * IRQ_WAKE_THREAD which will wake up the handler thread and run
2135 * @thread_fn. This split handler design is necessary to support
2136 * shared interrupts.
2138 * Dev_id must be globally unique. Normally the address of the
2139 * device data structure is used as the cookie. Since the handler
2140 * receives this value it makes sense to use it.
2142 * If your interrupt is shared you must pass a non NULL dev_id
2143 * as this is required when freeing the interrupt.
2147 * IRQF_SHARED Interrupt is shared
2148 * IRQF_TRIGGER_* Specify active edge(s) or level
2149 * IRQF_ONESHOT Run thread_fn with interrupt line masked
2151 int request_threaded_irq(unsigned int irq, irq_handler_t handler,
2152 irq_handler_t thread_fn, unsigned long irqflags,
2153 const char *devname, void *dev_id)
2155 struct irqaction *action;
2156 struct irq_desc *desc;
2159 if (irq == IRQ_NOTCONNECTED)
2163 * Sanity-check: shared interrupts must pass in a real dev-ID,
2164 * otherwise we'll have trouble later trying to figure out
2165 * which interrupt is which (messes up the interrupt freeing
2168 * Also shared interrupts do not go well with disabling auto enable.
2169 * The sharing interrupt might request it while it's still disabled
2170 * and then wait for interrupts forever.
2172 * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
2173 * it cannot be set along with IRQF_NO_SUSPEND.
2175 if (((irqflags & IRQF_SHARED) && !dev_id) ||
2176 ((irqflags & IRQF_SHARED) && (irqflags & IRQF_NO_AUTOEN)) ||
2177 (!(irqflags & IRQF_SHARED) && (irqflags & IRQF_COND_SUSPEND)) ||
2178 ((irqflags & IRQF_NO_SUSPEND) && (irqflags & IRQF_COND_SUSPEND)))
2181 desc = irq_to_desc(irq);
2185 if (!irq_settings_can_request(desc) ||
2186 WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2192 handler = irq_default_primary_handler;
2195 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2199 action->handler = handler;
2200 action->thread_fn = thread_fn;
2201 action->flags = irqflags;
2202 action->name = devname;
2203 action->dev_id = dev_id;
2205 retval = irq_chip_pm_get(&desc->irq_data);
2211 retval = __setup_irq(irq, desc, action);
2214 irq_chip_pm_put(&desc->irq_data);
2215 kfree(action->secondary);
2219 #ifdef CONFIG_DEBUG_SHIRQ_FIXME
2220 if (!retval && (irqflags & IRQF_SHARED)) {
2222 * It's a shared IRQ -- the driver ought to be prepared for it
2223 * to happen immediately, so let's make sure....
2224 * We disable the irq to make sure that a 'real' IRQ doesn't
2225 * run in parallel with our fake.
2227 unsigned long flags;
2230 local_irq_save(flags);
2232 handler(irq, dev_id);
2234 local_irq_restore(flags);
2240 EXPORT_SYMBOL(request_threaded_irq);
2243 * request_any_context_irq - allocate an interrupt line
2244 * @irq: Interrupt line to allocate
2245 * @handler: Function to be called when the IRQ occurs.
2246 * Threaded handler for threaded interrupts.
2247 * @flags: Interrupt type flags
2248 * @name: An ascii name for the claiming device
2249 * @dev_id: A cookie passed back to the handler function
2251 * This call allocates interrupt resources and enables the
2252 * interrupt line and IRQ handling. It selects either a
2253 * hardirq or threaded handling method depending on the
2256 * On failure, it returns a negative value. On success,
2257 * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
2259 int request_any_context_irq(unsigned int irq, irq_handler_t handler,
2260 unsigned long flags, const char *name, void *dev_id)
2262 struct irq_desc *desc;
2265 if (irq == IRQ_NOTCONNECTED)
2268 desc = irq_to_desc(irq);
2272 if (irq_settings_is_nested_thread(desc)) {
2273 ret = request_threaded_irq(irq, NULL, handler,
2274 flags, name, dev_id);
2275 return !ret ? IRQC_IS_NESTED : ret;
2278 ret = request_irq(irq, handler, flags, name, dev_id);
2279 return !ret ? IRQC_IS_HARDIRQ : ret;
2281 EXPORT_SYMBOL_GPL(request_any_context_irq);
2284 * request_nmi - allocate an interrupt line for NMI delivery
2285 * @irq: Interrupt line to allocate
2286 * @handler: Function to be called when the IRQ occurs.
2287 * Threaded handler for threaded interrupts.
2288 * @irqflags: Interrupt type flags
2289 * @name: An ascii name for the claiming device
2290 * @dev_id: A cookie passed back to the handler function
2292 * This call allocates interrupt resources and enables the
2293 * interrupt line and IRQ handling. It sets up the IRQ line
2294 * to be handled as an NMI.
2296 * An interrupt line delivering NMIs cannot be shared and IRQ handling
2297 * cannot be threaded.
2299 * Interrupt lines requested for NMI delivering must produce per cpu
2300 * interrupts and have auto enabling setting disabled.
2302 * Dev_id must be globally unique. Normally the address of the
2303 * device data structure is used as the cookie. Since the handler
2304 * receives this value it makes sense to use it.
2306 * If the interrupt line cannot be used to deliver NMIs, function
2307 * will fail and return a negative value.
2309 int request_nmi(unsigned int irq, irq_handler_t handler,
2310 unsigned long irqflags, const char *name, void *dev_id)
2312 struct irqaction *action;
2313 struct irq_desc *desc;
2314 unsigned long flags;
2317 if (irq == IRQ_NOTCONNECTED)
2320 /* NMI cannot be shared, used for Polling */
2321 if (irqflags & (IRQF_SHARED | IRQF_COND_SUSPEND | IRQF_IRQPOLL))
2324 if (!(irqflags & IRQF_PERCPU))
2330 desc = irq_to_desc(irq);
2332 if (!desc || (irq_settings_can_autoenable(desc) &&
2333 !(irqflags & IRQF_NO_AUTOEN)) ||
2334 !irq_settings_can_request(desc) ||
2335 WARN_ON(irq_settings_is_per_cpu_devid(desc)) ||
2336 !irq_supports_nmi(desc))
2339 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2343 action->handler = handler;
2344 action->flags = irqflags | IRQF_NO_THREAD | IRQF_NOBALANCING;
2345 action->name = name;
2346 action->dev_id = dev_id;
2348 retval = irq_chip_pm_get(&desc->irq_data);
2352 retval = __setup_irq(irq, desc, action);
2356 raw_spin_lock_irqsave(&desc->lock, flags);
2358 /* Setup NMI state */
2359 desc->istate |= IRQS_NMI;
2360 retval = irq_nmi_setup(desc);
2362 __cleanup_nmi(irq, desc);
2363 raw_spin_unlock_irqrestore(&desc->lock, flags);
2367 raw_spin_unlock_irqrestore(&desc->lock, flags);
2372 irq_chip_pm_put(&desc->irq_data);
2379 void enable_percpu_irq(unsigned int irq, unsigned int type)
2381 unsigned int cpu = smp_processor_id();
2382 unsigned long flags;
2383 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2389 * If the trigger type is not specified by the caller, then
2390 * use the default for this interrupt.
2392 type &= IRQ_TYPE_SENSE_MASK;
2393 if (type == IRQ_TYPE_NONE)
2394 type = irqd_get_trigger_type(&desc->irq_data);
2396 if (type != IRQ_TYPE_NONE) {
2399 ret = __irq_set_trigger(desc, type);
2402 WARN(1, "failed to set type for IRQ%d\n", irq);
2407 irq_percpu_enable(desc, cpu);
2409 irq_put_desc_unlock(desc, flags);
2411 EXPORT_SYMBOL_GPL(enable_percpu_irq);
2413 void enable_percpu_nmi(unsigned int irq, unsigned int type)
2415 enable_percpu_irq(irq, type);
2419 * irq_percpu_is_enabled - Check whether the per cpu irq is enabled
2420 * @irq: Linux irq number to check for
2422 * Must be called from a non migratable context. Returns the enable
2423 * state of a per cpu interrupt on the current cpu.
2425 bool irq_percpu_is_enabled(unsigned int irq)
2427 unsigned int cpu = smp_processor_id();
2428 struct irq_desc *desc;
2429 unsigned long flags;
2432 desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2436 is_enabled = cpumask_test_cpu(cpu, desc->percpu_enabled);
2437 irq_put_desc_unlock(desc, flags);
2441 EXPORT_SYMBOL_GPL(irq_percpu_is_enabled);
2443 void disable_percpu_irq(unsigned int irq)
2445 unsigned int cpu = smp_processor_id();
2446 unsigned long flags;
2447 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2452 irq_percpu_disable(desc, cpu);
2453 irq_put_desc_unlock(desc, flags);
2455 EXPORT_SYMBOL_GPL(disable_percpu_irq);
2457 void disable_percpu_nmi(unsigned int irq)
2459 disable_percpu_irq(irq);
2463 * Internal function to unregister a percpu irqaction.
2465 static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_id)
2467 struct irq_desc *desc = irq_to_desc(irq);
2468 struct irqaction *action;
2469 unsigned long flags;
2471 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
2476 raw_spin_lock_irqsave(&desc->lock, flags);
2478 action = desc->action;
2479 if (!action || action->percpu_dev_id != dev_id) {
2480 WARN(1, "Trying to free already-free IRQ %d\n", irq);
2484 if (!cpumask_empty(desc->percpu_enabled)) {
2485 WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
2486 irq, cpumask_first(desc->percpu_enabled));
2490 /* Found it - now remove it from the list of entries: */
2491 desc->action = NULL;
2493 desc->istate &= ~IRQS_NMI;
2495 raw_spin_unlock_irqrestore(&desc->lock, flags);
2497 unregister_handler_proc(irq, action);
2499 irq_chip_pm_put(&desc->irq_data);
2500 module_put(desc->owner);
2504 raw_spin_unlock_irqrestore(&desc->lock, flags);
2509 * remove_percpu_irq - free a per-cpu interrupt
2510 * @irq: Interrupt line to free
2511 * @act: irqaction for the interrupt
2513 * Used to remove interrupts statically setup by the early boot process.
2515 void remove_percpu_irq(unsigned int irq, struct irqaction *act)
2517 struct irq_desc *desc = irq_to_desc(irq);
2519 if (desc && irq_settings_is_per_cpu_devid(desc))
2520 __free_percpu_irq(irq, act->percpu_dev_id);
2524 * free_percpu_irq - free an interrupt allocated with request_percpu_irq
2525 * @irq: Interrupt line to free
2526 * @dev_id: Device identity to free
2528 * Remove a percpu interrupt handler. The handler is removed, but
2529 * the interrupt line is not disabled. This must be done on each
2530 * CPU before calling this function. The function does not return
2531 * until any executing interrupts for this IRQ have completed.
2533 * This function must not be called from interrupt context.
2535 void free_percpu_irq(unsigned int irq, void __percpu *dev_id)
2537 struct irq_desc *desc = irq_to_desc(irq);
2539 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2542 chip_bus_lock(desc);
2543 kfree(__free_percpu_irq(irq, dev_id));
2544 chip_bus_sync_unlock(desc);
2546 EXPORT_SYMBOL_GPL(free_percpu_irq);
2548 void free_percpu_nmi(unsigned int irq, void __percpu *dev_id)
2550 struct irq_desc *desc = irq_to_desc(irq);
2552 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2555 if (WARN_ON(!irq_is_nmi(desc)))
2558 kfree(__free_percpu_irq(irq, dev_id));
2562 * setup_percpu_irq - setup a per-cpu interrupt
2563 * @irq: Interrupt line to setup
2564 * @act: irqaction for the interrupt
2566 * Used to statically setup per-cpu interrupts in the early boot process.
2568 int setup_percpu_irq(unsigned int irq, struct irqaction *act)
2570 struct irq_desc *desc = irq_to_desc(irq);
2573 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2576 retval = irq_chip_pm_get(&desc->irq_data);
2580 retval = __setup_irq(irq, desc, act);
2583 irq_chip_pm_put(&desc->irq_data);
2589 * __request_percpu_irq - allocate a percpu interrupt line
2590 * @irq: Interrupt line to allocate
2591 * @handler: Function to be called when the IRQ occurs.
2592 * @flags: Interrupt type flags (IRQF_TIMER only)
2593 * @devname: An ascii name for the claiming device
2594 * @dev_id: A percpu cookie passed back to the handler function
2596 * This call allocates interrupt resources and enables the
2597 * interrupt on the local CPU. If the interrupt is supposed to be
2598 * enabled on other CPUs, it has to be done on each CPU using
2599 * enable_percpu_irq().
2601 * Dev_id must be globally unique. It is a per-cpu variable, and
2602 * the handler gets called with the interrupted CPU's instance of
2605 int __request_percpu_irq(unsigned int irq, irq_handler_t handler,
2606 unsigned long flags, const char *devname,
2607 void __percpu *dev_id)
2609 struct irqaction *action;
2610 struct irq_desc *desc;
2616 desc = irq_to_desc(irq);
2617 if (!desc || !irq_settings_can_request(desc) ||
2618 !irq_settings_is_per_cpu_devid(desc))
2621 if (flags && flags != IRQF_TIMER)
2624 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2628 action->handler = handler;
2629 action->flags = flags | IRQF_PERCPU | IRQF_NO_SUSPEND;
2630 action->name = devname;
2631 action->percpu_dev_id = dev_id;
2633 retval = irq_chip_pm_get(&desc->irq_data);
2639 retval = __setup_irq(irq, desc, action);
2642 irq_chip_pm_put(&desc->irq_data);
2648 EXPORT_SYMBOL_GPL(__request_percpu_irq);
2651 * request_percpu_nmi - allocate a percpu interrupt line for NMI delivery
2652 * @irq: Interrupt line to allocate
2653 * @handler: Function to be called when the IRQ occurs.
2654 * @name: An ascii name for the claiming device
2655 * @dev_id: A percpu cookie passed back to the handler function
2657 * This call allocates interrupt resources for a per CPU NMI. Per CPU NMIs
2658 * have to be setup on each CPU by calling prepare_percpu_nmi() before
2659 * being enabled on the same CPU by using enable_percpu_nmi().
2661 * Dev_id must be globally unique. It is a per-cpu variable, and
2662 * the handler gets called with the interrupted CPU's instance of
2665 * Interrupt lines requested for NMI delivering should have auto enabling
2668 * If the interrupt line cannot be used to deliver NMIs, function
2669 * will fail returning a negative value.
2671 int request_percpu_nmi(unsigned int irq, irq_handler_t handler,
2672 const char *name, void __percpu *dev_id)
2674 struct irqaction *action;
2675 struct irq_desc *desc;
2676 unsigned long flags;
2682 desc = irq_to_desc(irq);
2684 if (!desc || !irq_settings_can_request(desc) ||
2685 !irq_settings_is_per_cpu_devid(desc) ||
2686 irq_settings_can_autoenable(desc) ||
2687 !irq_supports_nmi(desc))
2690 /* The line cannot already be NMI */
2691 if (irq_is_nmi(desc))
2694 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2698 action->handler = handler;
2699 action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND | IRQF_NO_THREAD
2701 action->name = name;
2702 action->percpu_dev_id = dev_id;
2704 retval = irq_chip_pm_get(&desc->irq_data);
2708 retval = __setup_irq(irq, desc, action);
2712 raw_spin_lock_irqsave(&desc->lock, flags);
2713 desc->istate |= IRQS_NMI;
2714 raw_spin_unlock_irqrestore(&desc->lock, flags);
2719 irq_chip_pm_put(&desc->irq_data);
2727 * prepare_percpu_nmi - performs CPU local setup for NMI delivery
2728 * @irq: Interrupt line to prepare for NMI delivery
2730 * This call prepares an interrupt line to deliver NMI on the current CPU,
2731 * before that interrupt line gets enabled with enable_percpu_nmi().
2733 * As a CPU local operation, this should be called from non-preemptible
2736 * If the interrupt line cannot be used to deliver NMIs, function
2737 * will fail returning a negative value.
2739 int prepare_percpu_nmi(unsigned int irq)
2741 unsigned long flags;
2742 struct irq_desc *desc;
2745 WARN_ON(preemptible());
2747 desc = irq_get_desc_lock(irq, &flags,
2748 IRQ_GET_DESC_CHECK_PERCPU);
2752 if (WARN(!irq_is_nmi(desc),
2753 KERN_ERR "prepare_percpu_nmi called for a non-NMI interrupt: irq %u\n",
2759 ret = irq_nmi_setup(desc);
2761 pr_err("Failed to setup NMI delivery: irq %u\n", irq);
2766 irq_put_desc_unlock(desc, flags);
2771 * teardown_percpu_nmi - undoes NMI setup of IRQ line
2772 * @irq: Interrupt line from which CPU local NMI configuration should be
2775 * This call undoes the setup done by prepare_percpu_nmi().
2777 * IRQ line should not be enabled for the current CPU.
2779 * As a CPU local operation, this should be called from non-preemptible
2782 void teardown_percpu_nmi(unsigned int irq)
2784 unsigned long flags;
2785 struct irq_desc *desc;
2787 WARN_ON(preemptible());
2789 desc = irq_get_desc_lock(irq, &flags,
2790 IRQ_GET_DESC_CHECK_PERCPU);
2794 if (WARN_ON(!irq_is_nmi(desc)))
2797 irq_nmi_teardown(desc);
2799 irq_put_desc_unlock(desc, flags);
2802 int __irq_get_irqchip_state(struct irq_data *data, enum irqchip_irq_state which,
2805 struct irq_chip *chip;
2809 chip = irq_data_get_irq_chip(data);
2810 if (WARN_ON_ONCE(!chip))
2812 if (chip->irq_get_irqchip_state)
2814 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2815 data = data->parent_data;
2822 err = chip->irq_get_irqchip_state(data, which, state);
2827 * irq_get_irqchip_state - returns the irqchip state of a interrupt.
2828 * @irq: Interrupt line that is forwarded to a VM
2829 * @which: One of IRQCHIP_STATE_* the caller wants to know about
2830 * @state: a pointer to a boolean where the state is to be stored
2832 * This call snapshots the internal irqchip state of an
2833 * interrupt, returning into @state the bit corresponding to
2836 * This function should be called with preemption disabled if the
2837 * interrupt controller has per-cpu registers.
2839 int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2842 struct irq_desc *desc;
2843 struct irq_data *data;
2844 unsigned long flags;
2847 desc = irq_get_desc_buslock(irq, &flags, 0);
2851 data = irq_desc_get_irq_data(desc);
2853 err = __irq_get_irqchip_state(data, which, state);
2855 irq_put_desc_busunlock(desc, flags);
2858 EXPORT_SYMBOL_GPL(irq_get_irqchip_state);
2861 * irq_set_irqchip_state - set the state of a forwarded interrupt.
2862 * @irq: Interrupt line that is forwarded to a VM
2863 * @which: State to be restored (one of IRQCHIP_STATE_*)
2864 * @val: Value corresponding to @which
2866 * This call sets the internal irqchip state of an interrupt,
2867 * depending on the value of @which.
2869 * This function should be called with migration disabled if the
2870 * interrupt controller has per-cpu registers.
2872 int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2875 struct irq_desc *desc;
2876 struct irq_data *data;
2877 struct irq_chip *chip;
2878 unsigned long flags;
2881 desc = irq_get_desc_buslock(irq, &flags, 0);
2885 data = irq_desc_get_irq_data(desc);
2888 chip = irq_data_get_irq_chip(data);
2889 if (WARN_ON_ONCE(!chip)) {
2893 if (chip->irq_set_irqchip_state)
2895 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2896 data = data->parent_data;
2903 err = chip->irq_set_irqchip_state(data, which, val);
2906 irq_put_desc_busunlock(desc, flags);
2909 EXPORT_SYMBOL_GPL(irq_set_irqchip_state);
2912 * irq_has_action - Check whether an interrupt is requested
2913 * @irq: The linux irq number
2915 * Returns: A snapshot of the current state
2917 bool irq_has_action(unsigned int irq)
2922 res = irq_desc_has_action(irq_to_desc(irq));
2926 EXPORT_SYMBOL_GPL(irq_has_action);
2929 * irq_check_status_bit - Check whether bits in the irq descriptor status are set
2930 * @irq: The linux irq number
2931 * @bitmask: The bitmask to evaluate
2933 * Returns: True if one of the bits in @bitmask is set
2935 bool irq_check_status_bit(unsigned int irq, unsigned int bitmask)
2937 struct irq_desc *desc;
2941 desc = irq_to_desc(irq);
2943 res = !!(desc->status_use_accessors & bitmask);
2947 EXPORT_SYMBOL_GPL(irq_check_status_bit);