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 || desc->istate & IRQS_NMI)
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
805 * time. If it was already started up, then irq_startup()
806 * will invoke irq_enable() under the hood.
808 irq_startup(desc, IRQ_RESEND, IRQ_START_FORCE);
817 * enable_irq - enable handling of an irq
818 * @irq: Interrupt to enable
820 * Undoes the effect of one call to disable_irq(). If this
821 * matches the last disable, processing of interrupts on this
822 * IRQ line is re-enabled.
824 * This function may be called from IRQ context only when
825 * desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
827 void enable_irq(unsigned int irq)
830 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
834 if (WARN(!desc->irq_data.chip,
835 KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
840 irq_put_desc_busunlock(desc, flags);
842 EXPORT_SYMBOL(enable_irq);
845 * enable_nmi - enable handling of an nmi
846 * @irq: Interrupt to enable
848 * The interrupt to enable must have been requested through request_nmi.
849 * Undoes the effect of one call to disable_nmi(). If this
850 * matches the last disable, processing of interrupts on this
851 * IRQ line is re-enabled.
853 void enable_nmi(unsigned int irq)
858 static int set_irq_wake_real(unsigned int irq, unsigned int on)
860 struct irq_desc *desc = irq_to_desc(irq);
863 if (irq_desc_get_chip(desc)->flags & IRQCHIP_SKIP_SET_WAKE)
866 if (desc->irq_data.chip->irq_set_wake)
867 ret = desc->irq_data.chip->irq_set_wake(&desc->irq_data, on);
873 * irq_set_irq_wake - control irq power management wakeup
874 * @irq: interrupt to control
875 * @on: enable/disable power management wakeup
877 * Enable/disable power management wakeup mode, which is
878 * disabled by default. Enables and disables must match,
879 * just as they match for non-wakeup mode support.
881 * Wakeup mode lets this IRQ wake the system from sleep
882 * states like "suspend to RAM".
884 * Note: irq enable/disable state is completely orthogonal
885 * to the enable/disable state of irq wake. An irq can be
886 * disabled with disable_irq() and still wake the system as
887 * long as the irq has wake enabled. If this does not hold,
888 * then the underlying irq chip and the related driver need
889 * to be investigated.
891 int irq_set_irq_wake(unsigned int irq, unsigned int on)
894 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
900 /* Don't use NMIs as wake up interrupts please */
901 if (desc->istate & IRQS_NMI) {
906 /* wakeup-capable irqs can be shared between drivers that
907 * don't need to have the same sleep mode behaviors.
910 if (desc->wake_depth++ == 0) {
911 ret = set_irq_wake_real(irq, on);
913 desc->wake_depth = 0;
915 irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE);
918 if (desc->wake_depth == 0) {
919 WARN(1, "Unbalanced IRQ %d wake disable\n", irq);
920 } else if (--desc->wake_depth == 0) {
921 ret = set_irq_wake_real(irq, on);
923 desc->wake_depth = 1;
925 irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
930 irq_put_desc_busunlock(desc, flags);
933 EXPORT_SYMBOL(irq_set_irq_wake);
936 * Internal function that tells the architecture code whether a
937 * particular irq has been exclusively allocated or is available
940 int can_request_irq(unsigned int irq, unsigned long irqflags)
943 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
949 if (irq_settings_can_request(desc)) {
951 irqflags & desc->action->flags & IRQF_SHARED)
954 irq_put_desc_unlock(desc, flags);
958 int __irq_set_trigger(struct irq_desc *desc, unsigned long flags)
960 struct irq_chip *chip = desc->irq_data.chip;
963 if (!chip || !chip->irq_set_type) {
965 * IRQF_TRIGGER_* but the PIC does not support multiple
968 pr_debug("No set_type function for IRQ %d (%s)\n",
969 irq_desc_get_irq(desc),
970 chip ? (chip->name ? : "unknown") : "unknown");
974 if (chip->flags & IRQCHIP_SET_TYPE_MASKED) {
975 if (!irqd_irq_masked(&desc->irq_data))
977 if (!irqd_irq_disabled(&desc->irq_data))
981 /* Mask all flags except trigger mode */
982 flags &= IRQ_TYPE_SENSE_MASK;
983 ret = chip->irq_set_type(&desc->irq_data, flags);
986 case IRQ_SET_MASK_OK:
987 case IRQ_SET_MASK_OK_DONE:
988 irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK);
989 irqd_set(&desc->irq_data, flags);
992 case IRQ_SET_MASK_OK_NOCOPY:
993 flags = irqd_get_trigger_type(&desc->irq_data);
994 irq_settings_set_trigger_mask(desc, flags);
995 irqd_clear(&desc->irq_data, IRQD_LEVEL);
996 irq_settings_clr_level(desc);
997 if (flags & IRQ_TYPE_LEVEL_MASK) {
998 irq_settings_set_level(desc);
999 irqd_set(&desc->irq_data, IRQD_LEVEL);
1005 pr_err("Setting trigger mode %lu for irq %u failed (%pS)\n",
1006 flags, irq_desc_get_irq(desc), chip->irq_set_type);
1013 #ifdef CONFIG_HARDIRQS_SW_RESEND
1014 int irq_set_parent(int irq, int parent_irq)
1016 unsigned long flags;
1017 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
1022 desc->parent_irq = parent_irq;
1024 irq_put_desc_unlock(desc, flags);
1027 EXPORT_SYMBOL_GPL(irq_set_parent);
1031 * Default primary interrupt handler for threaded interrupts. Is
1032 * assigned as primary handler when request_threaded_irq is called
1033 * with handler == NULL. Useful for oneshot interrupts.
1035 static irqreturn_t irq_default_primary_handler(int irq, void *dev_id)
1037 return IRQ_WAKE_THREAD;
1041 * Primary handler for nested threaded interrupts. Should never be
1044 static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)
1046 WARN(1, "Primary handler called for nested irq %d\n", irq);
1050 static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id)
1052 WARN(1, "Secondary action handler called for irq %d\n", irq);
1058 * Check whether we need to change the affinity of the interrupt thread.
1060 static void irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
1065 if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags))
1068 __set_current_state(TASK_RUNNING);
1071 * In case we are out of memory we set IRQTF_AFFINITY again and
1072 * try again next time
1074 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {
1075 set_bit(IRQTF_AFFINITY, &action->thread_flags);
1079 raw_spin_lock_irq(&desc->lock);
1081 * This code is triggered unconditionally. Check the affinity
1082 * mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
1084 if (cpumask_available(desc->irq_common_data.affinity)) {
1085 const struct cpumask *m;
1087 m = irq_data_get_effective_affinity_mask(&desc->irq_data);
1088 cpumask_copy(mask, m);
1091 raw_spin_unlock_irq(&desc->lock);
1094 set_cpus_allowed_ptr(current, mask);
1095 free_cpumask_var(mask);
1098 static inline void irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { }
1101 static int irq_wait_for_interrupt(struct irq_desc *desc,
1102 struct irqaction *action)
1105 set_current_state(TASK_INTERRUPTIBLE);
1106 irq_thread_check_affinity(desc, action);
1108 if (kthread_should_stop()) {
1109 /* may need to run one last time */
1110 if (test_and_clear_bit(IRQTF_RUNTHREAD,
1111 &action->thread_flags)) {
1112 __set_current_state(TASK_RUNNING);
1115 __set_current_state(TASK_RUNNING);
1119 if (test_and_clear_bit(IRQTF_RUNTHREAD,
1120 &action->thread_flags)) {
1121 __set_current_state(TASK_RUNNING);
1129 * Oneshot interrupts keep the irq line masked until the threaded
1130 * handler finished. unmask if the interrupt has not been disabled and
1133 static void irq_finalize_oneshot(struct irq_desc *desc,
1134 struct irqaction *action)
1136 if (!(desc->istate & IRQS_ONESHOT) ||
1137 action->handler == irq_forced_secondary_handler)
1140 chip_bus_lock(desc);
1141 raw_spin_lock_irq(&desc->lock);
1144 * Implausible though it may be we need to protect us against
1145 * the following scenario:
1147 * The thread is faster done than the hard interrupt handler
1148 * on the other CPU. If we unmask the irq line then the
1149 * interrupt can come in again and masks the line, leaves due
1150 * to IRQS_INPROGRESS and the irq line is masked forever.
1152 * This also serializes the state of shared oneshot handlers
1153 * versus "desc->threads_oneshot |= action->thread_mask;" in
1154 * irq_wake_thread(). See the comment there which explains the
1157 if (unlikely(irqd_irq_inprogress(&desc->irq_data))) {
1158 raw_spin_unlock_irq(&desc->lock);
1159 chip_bus_sync_unlock(desc);
1165 * Now check again, whether the thread should run. Otherwise
1166 * we would clear the threads_oneshot bit of this thread which
1169 if (test_bit(IRQTF_RUNTHREAD, &action->thread_flags))
1172 desc->threads_oneshot &= ~action->thread_mask;
1174 if (!desc->threads_oneshot && !irqd_irq_disabled(&desc->irq_data) &&
1175 irqd_irq_masked(&desc->irq_data))
1176 unmask_threaded_irq(desc);
1179 raw_spin_unlock_irq(&desc->lock);
1180 chip_bus_sync_unlock(desc);
1184 * Interrupts which are not explicitly requested as threaded
1185 * interrupts rely on the implicit bh/preempt disable of the hard irq
1186 * context. So we need to disable bh here to avoid deadlocks and other
1190 irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
1195 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
1196 local_irq_disable();
1197 ret = action->thread_fn(action->irq, action->dev_id);
1198 if (ret == IRQ_HANDLED)
1199 atomic_inc(&desc->threads_handled);
1201 irq_finalize_oneshot(desc, action);
1202 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
1209 * Interrupts explicitly requested as threaded interrupts want to be
1210 * preemptible - many of them need to sleep and wait for slow busses to
1213 static irqreturn_t irq_thread_fn(struct irq_desc *desc,
1214 struct irqaction *action)
1218 ret = action->thread_fn(action->irq, action->dev_id);
1219 if (ret == IRQ_HANDLED)
1220 atomic_inc(&desc->threads_handled);
1222 irq_finalize_oneshot(desc, action);
1226 void wake_threads_waitq(struct irq_desc *desc)
1228 if (atomic_dec_and_test(&desc->threads_active))
1229 wake_up(&desc->wait_for_threads);
1232 static void irq_thread_dtor(struct callback_head *unused)
1234 struct task_struct *tsk = current;
1235 struct irq_desc *desc;
1236 struct irqaction *action;
1238 if (WARN_ON_ONCE(!(current->flags & PF_EXITING)))
1241 action = kthread_data(tsk);
1243 pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
1244 tsk->comm, tsk->pid, action->irq);
1247 desc = irq_to_desc(action->irq);
1249 * If IRQTF_RUNTHREAD is set, we need to decrement
1250 * desc->threads_active and wake possible waiters.
1252 if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
1253 wake_threads_waitq(desc);
1255 /* Prevent a stale desc->threads_oneshot */
1256 irq_finalize_oneshot(desc, action);
1259 static void irq_wake_secondary(struct irq_desc *desc, struct irqaction *action)
1261 struct irqaction *secondary = action->secondary;
1263 if (WARN_ON_ONCE(!secondary))
1266 raw_spin_lock_irq(&desc->lock);
1267 __irq_wake_thread(desc, secondary);
1268 raw_spin_unlock_irq(&desc->lock);
1272 * Internal function to notify that a interrupt thread is ready.
1274 static void irq_thread_set_ready(struct irq_desc *desc,
1275 struct irqaction *action)
1277 set_bit(IRQTF_READY, &action->thread_flags);
1278 wake_up(&desc->wait_for_threads);
1282 * Internal function to wake up a interrupt thread and wait until it is
1285 static void wake_up_and_wait_for_irq_thread_ready(struct irq_desc *desc,
1286 struct irqaction *action)
1288 if (!action || !action->thread)
1291 wake_up_process(action->thread);
1292 wait_event(desc->wait_for_threads,
1293 test_bit(IRQTF_READY, &action->thread_flags));
1297 * Interrupt handler thread
1299 static int irq_thread(void *data)
1301 struct callback_head on_exit_work;
1302 struct irqaction *action = data;
1303 struct irq_desc *desc = irq_to_desc(action->irq);
1304 irqreturn_t (*handler_fn)(struct irq_desc *desc,
1305 struct irqaction *action);
1307 irq_thread_set_ready(desc, action);
1309 sched_set_fifo(current);
1311 if (force_irqthreads() && test_bit(IRQTF_FORCED_THREAD,
1312 &action->thread_flags))
1313 handler_fn = irq_forced_thread_fn;
1315 handler_fn = irq_thread_fn;
1317 init_task_work(&on_exit_work, irq_thread_dtor);
1318 task_work_add(current, &on_exit_work, TWA_NONE);
1320 while (!irq_wait_for_interrupt(desc, action)) {
1321 irqreturn_t action_ret;
1323 action_ret = handler_fn(desc, action);
1324 if (action_ret == IRQ_WAKE_THREAD)
1325 irq_wake_secondary(desc, action);
1327 wake_threads_waitq(desc);
1331 * This is the regular exit path. __free_irq() is stopping the
1332 * thread via kthread_stop() after calling
1333 * synchronize_hardirq(). So neither IRQTF_RUNTHREAD nor the
1334 * oneshot mask bit can be set.
1336 task_work_cancel(current, irq_thread_dtor);
1341 * irq_wake_thread - wake the irq thread for the action identified by dev_id
1342 * @irq: Interrupt line
1343 * @dev_id: Device identity for which the thread should be woken
1346 void irq_wake_thread(unsigned int irq, void *dev_id)
1348 struct irq_desc *desc = irq_to_desc(irq);
1349 struct irqaction *action;
1350 unsigned long flags;
1352 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1355 raw_spin_lock_irqsave(&desc->lock, flags);
1356 for_each_action_of_desc(desc, action) {
1357 if (action->dev_id == dev_id) {
1359 __irq_wake_thread(desc, action);
1363 raw_spin_unlock_irqrestore(&desc->lock, flags);
1365 EXPORT_SYMBOL_GPL(irq_wake_thread);
1367 static int irq_setup_forced_threading(struct irqaction *new)
1369 if (!force_irqthreads())
1371 if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))
1375 * No further action required for interrupts which are requested as
1376 * threaded interrupts already
1378 if (new->handler == irq_default_primary_handler)
1381 new->flags |= IRQF_ONESHOT;
1384 * Handle the case where we have a real primary handler and a
1385 * thread handler. We force thread them as well by creating a
1388 if (new->handler && new->thread_fn) {
1389 /* Allocate the secondary action */
1390 new->secondary = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
1391 if (!new->secondary)
1393 new->secondary->handler = irq_forced_secondary_handler;
1394 new->secondary->thread_fn = new->thread_fn;
1395 new->secondary->dev_id = new->dev_id;
1396 new->secondary->irq = new->irq;
1397 new->secondary->name = new->name;
1399 /* Deal with the primary handler */
1400 set_bit(IRQTF_FORCED_THREAD, &new->thread_flags);
1401 new->thread_fn = new->handler;
1402 new->handler = irq_default_primary_handler;
1406 static int irq_request_resources(struct irq_desc *desc)
1408 struct irq_data *d = &desc->irq_data;
1409 struct irq_chip *c = d->chip;
1411 return c->irq_request_resources ? c->irq_request_resources(d) : 0;
1414 static void irq_release_resources(struct irq_desc *desc)
1416 struct irq_data *d = &desc->irq_data;
1417 struct irq_chip *c = d->chip;
1419 if (c->irq_release_resources)
1420 c->irq_release_resources(d);
1423 static bool irq_supports_nmi(struct irq_desc *desc)
1425 struct irq_data *d = irq_desc_get_irq_data(desc);
1427 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1428 /* Only IRQs directly managed by the root irqchip can be set as NMI */
1432 /* Don't support NMIs for chips behind a slow bus */
1433 if (d->chip->irq_bus_lock || d->chip->irq_bus_sync_unlock)
1436 return d->chip->flags & IRQCHIP_SUPPORTS_NMI;
1439 static int irq_nmi_setup(struct irq_desc *desc)
1441 struct irq_data *d = irq_desc_get_irq_data(desc);
1442 struct irq_chip *c = d->chip;
1444 return c->irq_nmi_setup ? c->irq_nmi_setup(d) : -EINVAL;
1447 static void irq_nmi_teardown(struct irq_desc *desc)
1449 struct irq_data *d = irq_desc_get_irq_data(desc);
1450 struct irq_chip *c = d->chip;
1452 if (c->irq_nmi_teardown)
1453 c->irq_nmi_teardown(d);
1457 setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
1459 struct task_struct *t;
1462 t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
1465 t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq,
1473 * We keep the reference to the task struct even if
1474 * the thread dies to avoid that the interrupt code
1475 * references an already freed task_struct.
1477 new->thread = get_task_struct(t);
1479 * Tell the thread to set its affinity. This is
1480 * important for shared interrupt handlers as we do
1481 * not invoke setup_affinity() for the secondary
1482 * handlers as everything is already set up. Even for
1483 * interrupts marked with IRQF_NO_BALANCE this is
1484 * correct as we want the thread to move to the cpu(s)
1485 * on which the requesting code placed the interrupt.
1487 set_bit(IRQTF_AFFINITY, &new->thread_flags);
1492 * Internal function to register an irqaction - typically used to
1493 * allocate special interrupts that are part of the architecture.
1497 * desc->request_mutex Provides serialization against a concurrent free_irq()
1498 * chip_bus_lock Provides serialization for slow bus operations
1499 * desc->lock Provides serialization against hard interrupts
1501 * chip_bus_lock and desc->lock are sufficient for all other management and
1502 * interrupt related functions. desc->request_mutex solely serializes
1503 * request/free_irq().
1506 __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
1508 struct irqaction *old, **old_ptr;
1509 unsigned long flags, thread_mask = 0;
1510 int ret, nested, shared = 0;
1515 if (desc->irq_data.chip == &no_irq_chip)
1517 if (!try_module_get(desc->owner))
1523 * If the trigger type is not specified by the caller,
1524 * then use the default for this interrupt.
1526 if (!(new->flags & IRQF_TRIGGER_MASK))
1527 new->flags |= irqd_get_trigger_type(&desc->irq_data);
1530 * Check whether the interrupt nests into another interrupt
1533 nested = irq_settings_is_nested_thread(desc);
1535 if (!new->thread_fn) {
1540 * Replace the primary handler which was provided from
1541 * the driver for non nested interrupt handling by the
1542 * dummy function which warns when called.
1544 new->handler = irq_nested_primary_handler;
1546 if (irq_settings_can_thread(desc)) {
1547 ret = irq_setup_forced_threading(new);
1554 * Create a handler thread when a thread function is supplied
1555 * and the interrupt does not nest into another interrupt
1558 if (new->thread_fn && !nested) {
1559 ret = setup_irq_thread(new, irq, false);
1562 if (new->secondary) {
1563 ret = setup_irq_thread(new->secondary, irq, true);
1570 * Drivers are often written to work w/o knowledge about the
1571 * underlying irq chip implementation, so a request for a
1572 * threaded irq without a primary hard irq context handler
1573 * requires the ONESHOT flag to be set. Some irq chips like
1574 * MSI based interrupts are per se one shot safe. Check the
1575 * chip flags, so we can avoid the unmask dance at the end of
1576 * the threaded handler for those.
1578 if (desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)
1579 new->flags &= ~IRQF_ONESHOT;
1582 * Protects against a concurrent __free_irq() call which might wait
1583 * for synchronize_hardirq() to complete without holding the optional
1584 * chip bus lock and desc->lock. Also protects against handing out
1585 * a recycled oneshot thread_mask bit while it's still in use by
1586 * its previous owner.
1588 mutex_lock(&desc->request_mutex);
1591 * Acquire bus lock as the irq_request_resources() callback below
1592 * might rely on the serialization or the magic power management
1593 * functions which are abusing the irq_bus_lock() callback,
1595 chip_bus_lock(desc);
1597 /* First installed action requests resources. */
1598 if (!desc->action) {
1599 ret = irq_request_resources(desc);
1601 pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
1602 new->name, irq, desc->irq_data.chip->name);
1603 goto out_bus_unlock;
1608 * The following block of code has to be executed atomically
1609 * protected against a concurrent interrupt and any of the other
1610 * management calls which are not serialized via
1611 * desc->request_mutex or the optional bus lock.
1613 raw_spin_lock_irqsave(&desc->lock, flags);
1614 old_ptr = &desc->action;
1618 * Can't share interrupts unless both agree to and are
1619 * the same type (level, edge, polarity). So both flag
1620 * fields must have IRQF_SHARED set and the bits which
1621 * set the trigger type must match. Also all must
1623 * Interrupt lines used for NMIs cannot be shared.
1625 unsigned int oldtype;
1627 if (desc->istate & IRQS_NMI) {
1628 pr_err("Invalid attempt to share NMI for %s (irq %d) on irqchip %s.\n",
1629 new->name, irq, desc->irq_data.chip->name);
1635 * If nobody did set the configuration before, inherit
1636 * the one provided by the requester.
1638 if (irqd_trigger_type_was_set(&desc->irq_data)) {
1639 oldtype = irqd_get_trigger_type(&desc->irq_data);
1641 oldtype = new->flags & IRQF_TRIGGER_MASK;
1642 irqd_set_trigger_type(&desc->irq_data, oldtype);
1645 if (!((old->flags & new->flags) & IRQF_SHARED) ||
1646 (oldtype != (new->flags & IRQF_TRIGGER_MASK)) ||
1647 ((old->flags ^ new->flags) & IRQF_ONESHOT))
1650 /* All handlers must agree on per-cpuness */
1651 if ((old->flags & IRQF_PERCPU) !=
1652 (new->flags & IRQF_PERCPU))
1655 /* add new interrupt at end of irq queue */
1658 * Or all existing action->thread_mask bits,
1659 * so we can find the next zero bit for this
1662 thread_mask |= old->thread_mask;
1663 old_ptr = &old->next;
1670 * Setup the thread mask for this irqaction for ONESHOT. For
1671 * !ONESHOT irqs the thread mask is 0 so we can avoid a
1672 * conditional in irq_wake_thread().
1674 if (new->flags & IRQF_ONESHOT) {
1676 * Unlikely to have 32 resp 64 irqs sharing one line,
1679 if (thread_mask == ~0UL) {
1684 * The thread_mask for the action is or'ed to
1685 * desc->thread_active to indicate that the
1686 * IRQF_ONESHOT thread handler has been woken, but not
1687 * yet finished. The bit is cleared when a thread
1688 * completes. When all threads of a shared interrupt
1689 * line have completed desc->threads_active becomes
1690 * zero and the interrupt line is unmasked. See
1691 * handle.c:irq_wake_thread() for further information.
1693 * If no thread is woken by primary (hard irq context)
1694 * interrupt handlers, then desc->threads_active is
1695 * also checked for zero to unmask the irq line in the
1696 * affected hard irq flow handlers
1697 * (handle_[fasteoi|level]_irq).
1699 * The new action gets the first zero bit of
1700 * thread_mask assigned. See the loop above which or's
1701 * all existing action->thread_mask bits.
1703 new->thread_mask = 1UL << ffz(thread_mask);
1705 } else if (new->handler == irq_default_primary_handler &&
1706 !(desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)) {
1708 * The interrupt was requested with handler = NULL, so
1709 * we use the default primary handler for it. But it
1710 * does not have the oneshot flag set. In combination
1711 * with level interrupts this is deadly, because the
1712 * default primary handler just wakes the thread, then
1713 * the irq lines is reenabled, but the device still
1714 * has the level irq asserted. Rinse and repeat....
1716 * While this works for edge type interrupts, we play
1717 * it safe and reject unconditionally because we can't
1718 * say for sure which type this interrupt really
1719 * has. The type flags are unreliable as the
1720 * underlying chip implementation can override them.
1722 pr_err("Threaded irq requested with handler=NULL and !ONESHOT for %s (irq %d)\n",
1729 /* Setup the type (level, edge polarity) if configured: */
1730 if (new->flags & IRQF_TRIGGER_MASK) {
1731 ret = __irq_set_trigger(desc,
1732 new->flags & IRQF_TRIGGER_MASK);
1739 * Activate the interrupt. That activation must happen
1740 * independently of IRQ_NOAUTOEN. request_irq() can fail
1741 * and the callers are supposed to handle
1742 * that. enable_irq() of an interrupt requested with
1743 * IRQ_NOAUTOEN is not supposed to fail. The activation
1744 * keeps it in shutdown mode, it merily associates
1745 * resources if necessary and if that's not possible it
1746 * fails. Interrupts which are in managed shutdown mode
1747 * will simply ignore that activation request.
1749 ret = irq_activate(desc);
1753 desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \
1754 IRQS_ONESHOT | IRQS_WAITING);
1755 irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
1757 if (new->flags & IRQF_PERCPU) {
1758 irqd_set(&desc->irq_data, IRQD_PER_CPU);
1759 irq_settings_set_per_cpu(desc);
1760 if (new->flags & IRQF_NO_DEBUG)
1761 irq_settings_set_no_debug(desc);
1765 irq_settings_set_no_debug(desc);
1767 if (new->flags & IRQF_ONESHOT)
1768 desc->istate |= IRQS_ONESHOT;
1770 /* Exclude IRQ from balancing if requested */
1771 if (new->flags & IRQF_NOBALANCING) {
1772 irq_settings_set_no_balancing(desc);
1773 irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
1776 if (!(new->flags & IRQF_NO_AUTOEN) &&
1777 irq_settings_can_autoenable(desc)) {
1778 irq_startup(desc, IRQ_RESEND, IRQ_START_COND);
1781 * Shared interrupts do not go well with disabling
1782 * auto enable. The sharing interrupt might request
1783 * it while it's still disabled and then wait for
1784 * interrupts forever.
1786 WARN_ON_ONCE(new->flags & IRQF_SHARED);
1787 /* Undo nested disables: */
1791 } else if (new->flags & IRQF_TRIGGER_MASK) {
1792 unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK;
1793 unsigned int omsk = irqd_get_trigger_type(&desc->irq_data);
1796 /* hope the handler works with current trigger mode */
1797 pr_warn("irq %d uses trigger mode %u; requested %u\n",
1803 irq_pm_install_action(desc, new);
1805 /* Reset broken irq detection when installing new handler */
1806 desc->irq_count = 0;
1807 desc->irqs_unhandled = 0;
1810 * Check whether we disabled the irq via the spurious handler
1811 * before. Reenable it and give it another chance.
1813 if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) {
1814 desc->istate &= ~IRQS_SPURIOUS_DISABLED;
1818 raw_spin_unlock_irqrestore(&desc->lock, flags);
1819 chip_bus_sync_unlock(desc);
1820 mutex_unlock(&desc->request_mutex);
1822 irq_setup_timings(desc, new);
1824 wake_up_and_wait_for_irq_thread_ready(desc, new);
1825 wake_up_and_wait_for_irq_thread_ready(desc, new->secondary);
1827 register_irq_proc(irq, desc);
1829 register_handler_proc(irq, new);
1833 if (!(new->flags & IRQF_PROBE_SHARED)) {
1834 pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
1835 irq, new->flags, new->name, old->flags, old->name);
1836 #ifdef CONFIG_DEBUG_SHIRQ
1843 raw_spin_unlock_irqrestore(&desc->lock, flags);
1846 irq_release_resources(desc);
1848 chip_bus_sync_unlock(desc);
1849 mutex_unlock(&desc->request_mutex);
1853 struct task_struct *t = new->thread;
1856 kthread_stop_put(t);
1858 if (new->secondary && new->secondary->thread) {
1859 struct task_struct *t = new->secondary->thread;
1861 new->secondary->thread = NULL;
1862 kthread_stop_put(t);
1865 module_put(desc->owner);
1870 * Internal function to unregister an irqaction - used to free
1871 * regular and special interrupts that are part of the architecture.
1873 static struct irqaction *__free_irq(struct irq_desc *desc, void *dev_id)
1875 unsigned irq = desc->irq_data.irq;
1876 struct irqaction *action, **action_ptr;
1877 unsigned long flags;
1879 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
1881 mutex_lock(&desc->request_mutex);
1882 chip_bus_lock(desc);
1883 raw_spin_lock_irqsave(&desc->lock, flags);
1886 * There can be multiple actions per IRQ descriptor, find the right
1887 * one based on the dev_id:
1889 action_ptr = &desc->action;
1891 action = *action_ptr;
1894 WARN(1, "Trying to free already-free IRQ %d\n", irq);
1895 raw_spin_unlock_irqrestore(&desc->lock, flags);
1896 chip_bus_sync_unlock(desc);
1897 mutex_unlock(&desc->request_mutex);
1901 if (action->dev_id == dev_id)
1903 action_ptr = &action->next;
1906 /* Found it - now remove it from the list of entries: */
1907 *action_ptr = action->next;
1909 irq_pm_remove_action(desc, action);
1911 /* If this was the last handler, shut down the IRQ line: */
1912 if (!desc->action) {
1913 irq_settings_clr_disable_unlazy(desc);
1914 /* Only shutdown. Deactivate after synchronize_hardirq() */
1919 /* make sure affinity_hint is cleaned up */
1920 if (WARN_ON_ONCE(desc->affinity_hint))
1921 desc->affinity_hint = NULL;
1924 raw_spin_unlock_irqrestore(&desc->lock, flags);
1926 * Drop bus_lock here so the changes which were done in the chip
1927 * callbacks above are synced out to the irq chips which hang
1928 * behind a slow bus (I2C, SPI) before calling synchronize_hardirq().
1930 * Aside of that the bus_lock can also be taken from the threaded
1931 * handler in irq_finalize_oneshot() which results in a deadlock
1932 * because kthread_stop() would wait forever for the thread to
1933 * complete, which is blocked on the bus lock.
1935 * The still held desc->request_mutex() protects against a
1936 * concurrent request_irq() of this irq so the release of resources
1937 * and timing data is properly serialized.
1939 chip_bus_sync_unlock(desc);
1941 unregister_handler_proc(irq, action);
1944 * Make sure it's not being used on another CPU and if the chip
1945 * supports it also make sure that there is no (not yet serviced)
1946 * interrupt in flight at the hardware level.
1948 __synchronize_irq(desc);
1950 #ifdef CONFIG_DEBUG_SHIRQ
1952 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
1953 * event to happen even now it's being freed, so let's make sure that
1954 * is so by doing an extra call to the handler ....
1956 * ( We do this after actually deregistering it, to make sure that a
1957 * 'real' IRQ doesn't run in parallel with our fake. )
1959 if (action->flags & IRQF_SHARED) {
1960 local_irq_save(flags);
1961 action->handler(irq, dev_id);
1962 local_irq_restore(flags);
1967 * The action has already been removed above, but the thread writes
1968 * its oneshot mask bit when it completes. Though request_mutex is
1969 * held across this which prevents __setup_irq() from handing out
1970 * the same bit to a newly requested action.
1972 if (action->thread) {
1973 kthread_stop_put(action->thread);
1974 if (action->secondary && action->secondary->thread)
1975 kthread_stop_put(action->secondary->thread);
1978 /* Last action releases resources */
1979 if (!desc->action) {
1981 * Reacquire bus lock as irq_release_resources() might
1982 * require it to deallocate resources over the slow bus.
1984 chip_bus_lock(desc);
1986 * There is no interrupt on the fly anymore. Deactivate it
1989 raw_spin_lock_irqsave(&desc->lock, flags);
1990 irq_domain_deactivate_irq(&desc->irq_data);
1991 raw_spin_unlock_irqrestore(&desc->lock, flags);
1993 irq_release_resources(desc);
1994 chip_bus_sync_unlock(desc);
1995 irq_remove_timings(desc);
1998 mutex_unlock(&desc->request_mutex);
2000 irq_chip_pm_put(&desc->irq_data);
2001 module_put(desc->owner);
2002 kfree(action->secondary);
2007 * free_irq - free an interrupt allocated with request_irq
2008 * @irq: Interrupt line to free
2009 * @dev_id: Device identity to free
2011 * Remove an interrupt handler. The handler is removed and if the
2012 * interrupt line is no longer in use by any driver it is disabled.
2013 * On a shared IRQ the caller must ensure the interrupt is disabled
2014 * on the card it drives before calling this function. The function
2015 * does not return until any executing interrupts for this IRQ
2018 * This function must not be called from interrupt context.
2020 * Returns the devname argument passed to request_irq.
2022 const void *free_irq(unsigned int irq, void *dev_id)
2024 struct irq_desc *desc = irq_to_desc(irq);
2025 struct irqaction *action;
2026 const char *devname;
2028 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2032 if (WARN_ON(desc->affinity_notify))
2033 desc->affinity_notify = NULL;
2036 action = __free_irq(desc, dev_id);
2041 devname = action->name;
2045 EXPORT_SYMBOL(free_irq);
2047 /* This function must be called with desc->lock held */
2048 static const void *__cleanup_nmi(unsigned int irq, struct irq_desc *desc)
2050 const char *devname = NULL;
2052 desc->istate &= ~IRQS_NMI;
2054 if (!WARN_ON(desc->action == NULL)) {
2055 irq_pm_remove_action(desc, desc->action);
2056 devname = desc->action->name;
2057 unregister_handler_proc(irq, desc->action);
2059 kfree(desc->action);
2060 desc->action = NULL;
2063 irq_settings_clr_disable_unlazy(desc);
2064 irq_shutdown_and_deactivate(desc);
2066 irq_release_resources(desc);
2068 irq_chip_pm_put(&desc->irq_data);
2069 module_put(desc->owner);
2074 const void *free_nmi(unsigned int irq, void *dev_id)
2076 struct irq_desc *desc = irq_to_desc(irq);
2077 unsigned long flags;
2078 const void *devname;
2080 if (!desc || WARN_ON(!(desc->istate & IRQS_NMI)))
2083 if (WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2086 /* NMI still enabled */
2087 if (WARN_ON(desc->depth == 0))
2088 disable_nmi_nosync(irq);
2090 raw_spin_lock_irqsave(&desc->lock, flags);
2092 irq_nmi_teardown(desc);
2093 devname = __cleanup_nmi(irq, desc);
2095 raw_spin_unlock_irqrestore(&desc->lock, flags);
2101 * request_threaded_irq - allocate an interrupt line
2102 * @irq: Interrupt line to allocate
2103 * @handler: Function to be called when the IRQ occurs.
2104 * Primary handler for threaded interrupts.
2105 * If handler is NULL and thread_fn != NULL
2106 * the default primary handler is installed.
2107 * @thread_fn: Function called from the irq handler thread
2108 * If NULL, no irq thread is created
2109 * @irqflags: Interrupt type flags
2110 * @devname: An ascii name for the claiming device
2111 * @dev_id: A cookie passed back to the handler function
2113 * This call allocates interrupt resources and enables the
2114 * interrupt line and IRQ handling. From the point this
2115 * call is made your handler function may be invoked. Since
2116 * your handler function must clear any interrupt the board
2117 * raises, you must take care both to initialise your hardware
2118 * and to set up the interrupt handler in the right order.
2120 * If you want to set up a threaded irq handler for your device
2121 * then you need to supply @handler and @thread_fn. @handler is
2122 * still called in hard interrupt context and has to check
2123 * whether the interrupt originates from the device. If yes it
2124 * needs to disable the interrupt on the device and return
2125 * IRQ_WAKE_THREAD which will wake up the handler thread and run
2126 * @thread_fn. This split handler design is necessary to support
2127 * shared interrupts.
2129 * Dev_id must be globally unique. Normally the address of the
2130 * device data structure is used as the cookie. Since the handler
2131 * receives this value it makes sense to use it.
2133 * If your interrupt is shared you must pass a non NULL dev_id
2134 * as this is required when freeing the interrupt.
2138 * IRQF_SHARED Interrupt is shared
2139 * IRQF_TRIGGER_* Specify active edge(s) or level
2140 * IRQF_ONESHOT Run thread_fn with interrupt line masked
2142 int request_threaded_irq(unsigned int irq, irq_handler_t handler,
2143 irq_handler_t thread_fn, unsigned long irqflags,
2144 const char *devname, void *dev_id)
2146 struct irqaction *action;
2147 struct irq_desc *desc;
2150 if (irq == IRQ_NOTCONNECTED)
2154 * Sanity-check: shared interrupts must pass in a real dev-ID,
2155 * otherwise we'll have trouble later trying to figure out
2156 * which interrupt is which (messes up the interrupt freeing
2159 * Also shared interrupts do not go well with disabling auto enable.
2160 * The sharing interrupt might request it while it's still disabled
2161 * and then wait for interrupts forever.
2163 * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
2164 * it cannot be set along with IRQF_NO_SUSPEND.
2166 if (((irqflags & IRQF_SHARED) && !dev_id) ||
2167 ((irqflags & IRQF_SHARED) && (irqflags & IRQF_NO_AUTOEN)) ||
2168 (!(irqflags & IRQF_SHARED) && (irqflags & IRQF_COND_SUSPEND)) ||
2169 ((irqflags & IRQF_NO_SUSPEND) && (irqflags & IRQF_COND_SUSPEND)))
2172 desc = irq_to_desc(irq);
2176 if (!irq_settings_can_request(desc) ||
2177 WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2183 handler = irq_default_primary_handler;
2186 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2190 action->handler = handler;
2191 action->thread_fn = thread_fn;
2192 action->flags = irqflags;
2193 action->name = devname;
2194 action->dev_id = dev_id;
2196 retval = irq_chip_pm_get(&desc->irq_data);
2202 retval = __setup_irq(irq, desc, action);
2205 irq_chip_pm_put(&desc->irq_data);
2206 kfree(action->secondary);
2210 #ifdef CONFIG_DEBUG_SHIRQ_FIXME
2211 if (!retval && (irqflags & IRQF_SHARED)) {
2213 * It's a shared IRQ -- the driver ought to be prepared for it
2214 * to happen immediately, so let's make sure....
2215 * We disable the irq to make sure that a 'real' IRQ doesn't
2216 * run in parallel with our fake.
2218 unsigned long flags;
2221 local_irq_save(flags);
2223 handler(irq, dev_id);
2225 local_irq_restore(flags);
2231 EXPORT_SYMBOL(request_threaded_irq);
2234 * request_any_context_irq - allocate an interrupt line
2235 * @irq: Interrupt line to allocate
2236 * @handler: Function to be called when the IRQ occurs.
2237 * Threaded handler for threaded interrupts.
2238 * @flags: Interrupt type flags
2239 * @name: An ascii name for the claiming device
2240 * @dev_id: A cookie passed back to the handler function
2242 * This call allocates interrupt resources and enables the
2243 * interrupt line and IRQ handling. It selects either a
2244 * hardirq or threaded handling method depending on the
2247 * On failure, it returns a negative value. On success,
2248 * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
2250 int request_any_context_irq(unsigned int irq, irq_handler_t handler,
2251 unsigned long flags, const char *name, void *dev_id)
2253 struct irq_desc *desc;
2256 if (irq == IRQ_NOTCONNECTED)
2259 desc = irq_to_desc(irq);
2263 if (irq_settings_is_nested_thread(desc)) {
2264 ret = request_threaded_irq(irq, NULL, handler,
2265 flags, name, dev_id);
2266 return !ret ? IRQC_IS_NESTED : ret;
2269 ret = request_irq(irq, handler, flags, name, dev_id);
2270 return !ret ? IRQC_IS_HARDIRQ : ret;
2272 EXPORT_SYMBOL_GPL(request_any_context_irq);
2275 * request_nmi - allocate an interrupt line for NMI delivery
2276 * @irq: Interrupt line to allocate
2277 * @handler: Function to be called when the IRQ occurs.
2278 * Threaded handler for threaded interrupts.
2279 * @irqflags: Interrupt type flags
2280 * @name: An ascii name for the claiming device
2281 * @dev_id: A cookie passed back to the handler function
2283 * This call allocates interrupt resources and enables the
2284 * interrupt line and IRQ handling. It sets up the IRQ line
2285 * to be handled as an NMI.
2287 * An interrupt line delivering NMIs cannot be shared and IRQ handling
2288 * cannot be threaded.
2290 * Interrupt lines requested for NMI delivering must produce per cpu
2291 * interrupts and have auto enabling setting disabled.
2293 * Dev_id must be globally unique. Normally the address of the
2294 * device data structure is used as the cookie. Since the handler
2295 * receives this value it makes sense to use it.
2297 * If the interrupt line cannot be used to deliver NMIs, function
2298 * will fail and return a negative value.
2300 int request_nmi(unsigned int irq, irq_handler_t handler,
2301 unsigned long irqflags, const char *name, void *dev_id)
2303 struct irqaction *action;
2304 struct irq_desc *desc;
2305 unsigned long flags;
2308 if (irq == IRQ_NOTCONNECTED)
2311 /* NMI cannot be shared, used for Polling */
2312 if (irqflags & (IRQF_SHARED | IRQF_COND_SUSPEND | IRQF_IRQPOLL))
2315 if (!(irqflags & IRQF_PERCPU))
2321 desc = irq_to_desc(irq);
2323 if (!desc || (irq_settings_can_autoenable(desc) &&
2324 !(irqflags & IRQF_NO_AUTOEN)) ||
2325 !irq_settings_can_request(desc) ||
2326 WARN_ON(irq_settings_is_per_cpu_devid(desc)) ||
2327 !irq_supports_nmi(desc))
2330 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2334 action->handler = handler;
2335 action->flags = irqflags | IRQF_NO_THREAD | IRQF_NOBALANCING;
2336 action->name = name;
2337 action->dev_id = dev_id;
2339 retval = irq_chip_pm_get(&desc->irq_data);
2343 retval = __setup_irq(irq, desc, action);
2347 raw_spin_lock_irqsave(&desc->lock, flags);
2349 /* Setup NMI state */
2350 desc->istate |= IRQS_NMI;
2351 retval = irq_nmi_setup(desc);
2353 __cleanup_nmi(irq, desc);
2354 raw_spin_unlock_irqrestore(&desc->lock, flags);
2358 raw_spin_unlock_irqrestore(&desc->lock, flags);
2363 irq_chip_pm_put(&desc->irq_data);
2370 void enable_percpu_irq(unsigned int irq, unsigned int type)
2372 unsigned int cpu = smp_processor_id();
2373 unsigned long flags;
2374 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2380 * If the trigger type is not specified by the caller, then
2381 * use the default for this interrupt.
2383 type &= IRQ_TYPE_SENSE_MASK;
2384 if (type == IRQ_TYPE_NONE)
2385 type = irqd_get_trigger_type(&desc->irq_data);
2387 if (type != IRQ_TYPE_NONE) {
2390 ret = __irq_set_trigger(desc, type);
2393 WARN(1, "failed to set type for IRQ%d\n", irq);
2398 irq_percpu_enable(desc, cpu);
2400 irq_put_desc_unlock(desc, flags);
2402 EXPORT_SYMBOL_GPL(enable_percpu_irq);
2404 void enable_percpu_nmi(unsigned int irq, unsigned int type)
2406 enable_percpu_irq(irq, type);
2410 * irq_percpu_is_enabled - Check whether the per cpu irq is enabled
2411 * @irq: Linux irq number to check for
2413 * Must be called from a non migratable context. Returns the enable
2414 * state of a per cpu interrupt on the current cpu.
2416 bool irq_percpu_is_enabled(unsigned int irq)
2418 unsigned int cpu = smp_processor_id();
2419 struct irq_desc *desc;
2420 unsigned long flags;
2423 desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2427 is_enabled = cpumask_test_cpu(cpu, desc->percpu_enabled);
2428 irq_put_desc_unlock(desc, flags);
2432 EXPORT_SYMBOL_GPL(irq_percpu_is_enabled);
2434 void disable_percpu_irq(unsigned int irq)
2436 unsigned int cpu = smp_processor_id();
2437 unsigned long flags;
2438 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2443 irq_percpu_disable(desc, cpu);
2444 irq_put_desc_unlock(desc, flags);
2446 EXPORT_SYMBOL_GPL(disable_percpu_irq);
2448 void disable_percpu_nmi(unsigned int irq)
2450 disable_percpu_irq(irq);
2454 * Internal function to unregister a percpu irqaction.
2456 static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_id)
2458 struct irq_desc *desc = irq_to_desc(irq);
2459 struct irqaction *action;
2460 unsigned long flags;
2462 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
2467 raw_spin_lock_irqsave(&desc->lock, flags);
2469 action = desc->action;
2470 if (!action || action->percpu_dev_id != dev_id) {
2471 WARN(1, "Trying to free already-free IRQ %d\n", irq);
2475 if (!cpumask_empty(desc->percpu_enabled)) {
2476 WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
2477 irq, cpumask_first(desc->percpu_enabled));
2481 /* Found it - now remove it from the list of entries: */
2482 desc->action = NULL;
2484 desc->istate &= ~IRQS_NMI;
2486 raw_spin_unlock_irqrestore(&desc->lock, flags);
2488 unregister_handler_proc(irq, action);
2490 irq_chip_pm_put(&desc->irq_data);
2491 module_put(desc->owner);
2495 raw_spin_unlock_irqrestore(&desc->lock, flags);
2500 * remove_percpu_irq - free a per-cpu interrupt
2501 * @irq: Interrupt line to free
2502 * @act: irqaction for the interrupt
2504 * Used to remove interrupts statically setup by the early boot process.
2506 void remove_percpu_irq(unsigned int irq, struct irqaction *act)
2508 struct irq_desc *desc = irq_to_desc(irq);
2510 if (desc && irq_settings_is_per_cpu_devid(desc))
2511 __free_percpu_irq(irq, act->percpu_dev_id);
2515 * free_percpu_irq - free an interrupt allocated with request_percpu_irq
2516 * @irq: Interrupt line to free
2517 * @dev_id: Device identity to free
2519 * Remove a percpu interrupt handler. The handler is removed, but
2520 * the interrupt line is not disabled. This must be done on each
2521 * CPU before calling this function. The function does not return
2522 * until any executing interrupts for this IRQ have completed.
2524 * This function must not be called from interrupt context.
2526 void free_percpu_irq(unsigned int irq, void __percpu *dev_id)
2528 struct irq_desc *desc = irq_to_desc(irq);
2530 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2533 chip_bus_lock(desc);
2534 kfree(__free_percpu_irq(irq, dev_id));
2535 chip_bus_sync_unlock(desc);
2537 EXPORT_SYMBOL_GPL(free_percpu_irq);
2539 void free_percpu_nmi(unsigned int irq, void __percpu *dev_id)
2541 struct irq_desc *desc = irq_to_desc(irq);
2543 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2546 if (WARN_ON(!(desc->istate & IRQS_NMI)))
2549 kfree(__free_percpu_irq(irq, dev_id));
2553 * setup_percpu_irq - setup a per-cpu interrupt
2554 * @irq: Interrupt line to setup
2555 * @act: irqaction for the interrupt
2557 * Used to statically setup per-cpu interrupts in the early boot process.
2559 int setup_percpu_irq(unsigned int irq, struct irqaction *act)
2561 struct irq_desc *desc = irq_to_desc(irq);
2564 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2567 retval = irq_chip_pm_get(&desc->irq_data);
2571 retval = __setup_irq(irq, desc, act);
2574 irq_chip_pm_put(&desc->irq_data);
2580 * __request_percpu_irq - allocate a percpu interrupt line
2581 * @irq: Interrupt line to allocate
2582 * @handler: Function to be called when the IRQ occurs.
2583 * @flags: Interrupt type flags (IRQF_TIMER only)
2584 * @devname: An ascii name for the claiming device
2585 * @dev_id: A percpu cookie passed back to the handler function
2587 * This call allocates interrupt resources and enables the
2588 * interrupt on the local CPU. If the interrupt is supposed to be
2589 * enabled on other CPUs, it has to be done on each CPU using
2590 * enable_percpu_irq().
2592 * Dev_id must be globally unique. It is a per-cpu variable, and
2593 * the handler gets called with the interrupted CPU's instance of
2596 int __request_percpu_irq(unsigned int irq, irq_handler_t handler,
2597 unsigned long flags, const char *devname,
2598 void __percpu *dev_id)
2600 struct irqaction *action;
2601 struct irq_desc *desc;
2607 desc = irq_to_desc(irq);
2608 if (!desc || !irq_settings_can_request(desc) ||
2609 !irq_settings_is_per_cpu_devid(desc))
2612 if (flags && flags != IRQF_TIMER)
2615 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2619 action->handler = handler;
2620 action->flags = flags | IRQF_PERCPU | IRQF_NO_SUSPEND;
2621 action->name = devname;
2622 action->percpu_dev_id = dev_id;
2624 retval = irq_chip_pm_get(&desc->irq_data);
2630 retval = __setup_irq(irq, desc, action);
2633 irq_chip_pm_put(&desc->irq_data);
2639 EXPORT_SYMBOL_GPL(__request_percpu_irq);
2642 * request_percpu_nmi - allocate a percpu interrupt line for NMI delivery
2643 * @irq: Interrupt line to allocate
2644 * @handler: Function to be called when the IRQ occurs.
2645 * @name: An ascii name for the claiming device
2646 * @dev_id: A percpu cookie passed back to the handler function
2648 * This call allocates interrupt resources for a per CPU NMI. Per CPU NMIs
2649 * have to be setup on each CPU by calling prepare_percpu_nmi() before
2650 * being enabled on the same CPU by using enable_percpu_nmi().
2652 * Dev_id must be globally unique. It is a per-cpu variable, and
2653 * the handler gets called with the interrupted CPU's instance of
2656 * Interrupt lines requested for NMI delivering should have auto enabling
2659 * If the interrupt line cannot be used to deliver NMIs, function
2660 * will fail returning a negative value.
2662 int request_percpu_nmi(unsigned int irq, irq_handler_t handler,
2663 const char *name, void __percpu *dev_id)
2665 struct irqaction *action;
2666 struct irq_desc *desc;
2667 unsigned long flags;
2673 desc = irq_to_desc(irq);
2675 if (!desc || !irq_settings_can_request(desc) ||
2676 !irq_settings_is_per_cpu_devid(desc) ||
2677 irq_settings_can_autoenable(desc) ||
2678 !irq_supports_nmi(desc))
2681 /* The line cannot already be NMI */
2682 if (desc->istate & IRQS_NMI)
2685 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2689 action->handler = handler;
2690 action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND | IRQF_NO_THREAD
2692 action->name = name;
2693 action->percpu_dev_id = dev_id;
2695 retval = irq_chip_pm_get(&desc->irq_data);
2699 retval = __setup_irq(irq, desc, action);
2703 raw_spin_lock_irqsave(&desc->lock, flags);
2704 desc->istate |= IRQS_NMI;
2705 raw_spin_unlock_irqrestore(&desc->lock, flags);
2710 irq_chip_pm_put(&desc->irq_data);
2718 * prepare_percpu_nmi - performs CPU local setup for NMI delivery
2719 * @irq: Interrupt line to prepare for NMI delivery
2721 * This call prepares an interrupt line to deliver NMI on the current CPU,
2722 * before that interrupt line gets enabled with enable_percpu_nmi().
2724 * As a CPU local operation, this should be called from non-preemptible
2727 * If the interrupt line cannot be used to deliver NMIs, function
2728 * will fail returning a negative value.
2730 int prepare_percpu_nmi(unsigned int irq)
2732 unsigned long flags;
2733 struct irq_desc *desc;
2736 WARN_ON(preemptible());
2738 desc = irq_get_desc_lock(irq, &flags,
2739 IRQ_GET_DESC_CHECK_PERCPU);
2743 if (WARN(!(desc->istate & IRQS_NMI),
2744 KERN_ERR "prepare_percpu_nmi called for a non-NMI interrupt: irq %u\n",
2750 ret = irq_nmi_setup(desc);
2752 pr_err("Failed to setup NMI delivery: irq %u\n", irq);
2757 irq_put_desc_unlock(desc, flags);
2762 * teardown_percpu_nmi - undoes NMI setup of IRQ line
2763 * @irq: Interrupt line from which CPU local NMI configuration should be
2766 * This call undoes the setup done by prepare_percpu_nmi().
2768 * IRQ line should not be enabled for the current CPU.
2770 * As a CPU local operation, this should be called from non-preemptible
2773 void teardown_percpu_nmi(unsigned int irq)
2775 unsigned long flags;
2776 struct irq_desc *desc;
2778 WARN_ON(preemptible());
2780 desc = irq_get_desc_lock(irq, &flags,
2781 IRQ_GET_DESC_CHECK_PERCPU);
2785 if (WARN_ON(!(desc->istate & IRQS_NMI)))
2788 irq_nmi_teardown(desc);
2790 irq_put_desc_unlock(desc, flags);
2793 int __irq_get_irqchip_state(struct irq_data *data, enum irqchip_irq_state which,
2796 struct irq_chip *chip;
2800 chip = irq_data_get_irq_chip(data);
2801 if (WARN_ON_ONCE(!chip))
2803 if (chip->irq_get_irqchip_state)
2805 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2806 data = data->parent_data;
2813 err = chip->irq_get_irqchip_state(data, which, state);
2818 * irq_get_irqchip_state - returns the irqchip state of a interrupt.
2819 * @irq: Interrupt line that is forwarded to a VM
2820 * @which: One of IRQCHIP_STATE_* the caller wants to know about
2821 * @state: a pointer to a boolean where the state is to be stored
2823 * This call snapshots the internal irqchip state of an
2824 * interrupt, returning into @state the bit corresponding to
2827 * This function should be called with preemption disabled if the
2828 * interrupt controller has per-cpu registers.
2830 int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2833 struct irq_desc *desc;
2834 struct irq_data *data;
2835 unsigned long flags;
2838 desc = irq_get_desc_buslock(irq, &flags, 0);
2842 data = irq_desc_get_irq_data(desc);
2844 err = __irq_get_irqchip_state(data, which, state);
2846 irq_put_desc_busunlock(desc, flags);
2849 EXPORT_SYMBOL_GPL(irq_get_irqchip_state);
2852 * irq_set_irqchip_state - set the state of a forwarded interrupt.
2853 * @irq: Interrupt line that is forwarded to a VM
2854 * @which: State to be restored (one of IRQCHIP_STATE_*)
2855 * @val: Value corresponding to @which
2857 * This call sets the internal irqchip state of an interrupt,
2858 * depending on the value of @which.
2860 * This function should be called with migration disabled if the
2861 * interrupt controller has per-cpu registers.
2863 int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2866 struct irq_desc *desc;
2867 struct irq_data *data;
2868 struct irq_chip *chip;
2869 unsigned long flags;
2872 desc = irq_get_desc_buslock(irq, &flags, 0);
2876 data = irq_desc_get_irq_data(desc);
2879 chip = irq_data_get_irq_chip(data);
2880 if (WARN_ON_ONCE(!chip)) {
2884 if (chip->irq_set_irqchip_state)
2886 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2887 data = data->parent_data;
2894 err = chip->irq_set_irqchip_state(data, which, val);
2897 irq_put_desc_busunlock(desc, flags);
2900 EXPORT_SYMBOL_GPL(irq_set_irqchip_state);
2903 * irq_has_action - Check whether an interrupt is requested
2904 * @irq: The linux irq number
2906 * Returns: A snapshot of the current state
2908 bool irq_has_action(unsigned int irq)
2913 res = irq_desc_has_action(irq_to_desc(irq));
2917 EXPORT_SYMBOL_GPL(irq_has_action);
2920 * irq_check_status_bit - Check whether bits in the irq descriptor status are set
2921 * @irq: The linux irq number
2922 * @bitmask: The bitmask to evaluate
2924 * Returns: True if one of the bits in @bitmask is set
2926 bool irq_check_status_bit(unsigned int irq, unsigned int bitmask)
2928 struct irq_desc *desc;
2932 desc = irq_to_desc(irq);
2934 res = !!(desc->status_use_accessors & bitmask);
2938 EXPORT_SYMBOL_GPL(irq_check_status_bit);