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 __read_mostly bool force_irqthreads;
29 EXPORT_SYMBOL_GPL(force_irqthreads);
31 static int __init setup_forced_irqthreads(char *arg)
33 force_irqthreads = true;
36 early_param("threadirqs", setup_forced_irqthreads);
39 static void __synchronize_hardirq(struct irq_desc *desc, bool sync_chip)
41 struct irq_data *irqd = irq_desc_get_irq_data(desc);
48 * Wait until we're out of the critical section. This might
49 * give the wrong answer due to the lack of memory barriers.
51 while (irqd_irq_inprogress(&desc->irq_data))
54 /* Ok, that indicated we're done: double-check carefully. */
55 raw_spin_lock_irqsave(&desc->lock, flags);
56 inprogress = irqd_irq_inprogress(&desc->irq_data);
59 * If requested and supported, check at the chip whether it
60 * is in flight at the hardware level, i.e. already pending
61 * in a CPU and waiting for service and acknowledge.
63 if (!inprogress && sync_chip) {
65 * Ignore the return code. inprogress is only updated
66 * when the chip supports it.
68 __irq_get_irqchip_state(irqd, IRQCHIP_STATE_ACTIVE,
71 raw_spin_unlock_irqrestore(&desc->lock, flags);
73 /* Oops, that failed? */
78 * synchronize_hardirq - wait for pending hard IRQ handlers (on other CPUs)
79 * @irq: interrupt number to wait for
81 * This function waits for any pending hard IRQ handlers for this
82 * interrupt to complete before returning. If you use this
83 * function while holding a resource the IRQ handler may need you
84 * will deadlock. It does not take associated threaded handlers
87 * Do not use this for shutdown scenarios where you must be sure
88 * that all parts (hardirq and threaded handler) have completed.
90 * Returns: false if a threaded handler is active.
92 * This function may be called - with care - from IRQ context.
94 * It does not check whether there is an interrupt in flight at the
95 * hardware level, but not serviced yet, as this might deadlock when
96 * called with interrupts disabled and the target CPU of the interrupt
99 bool synchronize_hardirq(unsigned int irq)
101 struct irq_desc *desc = irq_to_desc(irq);
104 __synchronize_hardirq(desc, false);
105 return !atomic_read(&desc->threads_active);
110 EXPORT_SYMBOL(synchronize_hardirq);
113 * synchronize_irq - wait for pending IRQ handlers (on other CPUs)
114 * @irq: interrupt number to wait for
116 * This function waits for any pending IRQ handlers for this interrupt
117 * to complete before returning. If you use this function while
118 * holding a resource the IRQ handler may need you will deadlock.
120 * Can only be called from preemptible code as it might sleep when
121 * an interrupt thread is associated to @irq.
123 * It optionally makes sure (when the irq chip supports that method)
124 * that the interrupt is not pending in any CPU and waiting for
127 void synchronize_irq(unsigned int irq)
129 struct irq_desc *desc = irq_to_desc(irq);
132 __synchronize_hardirq(desc, true);
134 * We made sure that no hardirq handler is
135 * running. Now verify that no threaded handlers are
138 wait_event(desc->wait_for_threads,
139 !atomic_read(&desc->threads_active));
142 EXPORT_SYMBOL(synchronize_irq);
145 cpumask_var_t irq_default_affinity;
147 static bool __irq_can_set_affinity(struct irq_desc *desc)
149 if (!desc || !irqd_can_balance(&desc->irq_data) ||
150 !desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity)
156 * irq_can_set_affinity - Check if the affinity of a given irq can be set
157 * @irq: Interrupt to check
160 int irq_can_set_affinity(unsigned int irq)
162 return __irq_can_set_affinity(irq_to_desc(irq));
166 * irq_can_set_affinity_usr - Check if affinity of a irq can be set from user space
167 * @irq: Interrupt to check
169 * Like irq_can_set_affinity() above, but additionally checks for the
170 * AFFINITY_MANAGED flag.
172 bool irq_can_set_affinity_usr(unsigned int irq)
174 struct irq_desc *desc = irq_to_desc(irq);
176 return __irq_can_set_affinity(desc) &&
177 !irqd_affinity_is_managed(&desc->irq_data);
181 * irq_set_thread_affinity - Notify irq threads to adjust affinity
182 * @desc: irq descriptor which has affitnity changed
184 * We just set IRQTF_AFFINITY and delegate the affinity setting
185 * to the interrupt thread itself. We can not call
186 * set_cpus_allowed_ptr() here as we hold desc->lock and this
187 * code can be called from hard interrupt context.
189 void irq_set_thread_affinity(struct irq_desc *desc)
191 struct irqaction *action;
193 for_each_action_of_desc(desc, action)
195 set_bit(IRQTF_AFFINITY, &action->thread_flags);
198 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
199 static void irq_validate_effective_affinity(struct irq_data *data)
201 const struct cpumask *m = irq_data_get_effective_affinity_mask(data);
202 struct irq_chip *chip = irq_data_get_irq_chip(data);
204 if (!cpumask_empty(m))
206 pr_warn_once("irq_chip %s did not update eff. affinity mask of irq %u\n",
207 chip->name, data->irq);
210 static inline void irq_init_effective_affinity(struct irq_data *data,
211 const struct cpumask *mask)
213 cpumask_copy(irq_data_get_effective_affinity_mask(data), mask);
216 static inline void irq_validate_effective_affinity(struct irq_data *data) { }
217 static inline void irq_init_effective_affinity(struct irq_data *data,
218 const struct cpumask *mask) { }
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_FLAG_MANAGED_IRQ)) {
257 const struct cpumask *hk_mask;
259 hk_mask = housekeeping_cpumask(HK_FLAG_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, bool force)
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_init_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, force))
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);
389 int __irq_set_affinity(unsigned int irq, const struct cpumask *mask, bool force)
391 struct irq_desc *desc = irq_to_desc(irq);
398 raw_spin_lock_irqsave(&desc->lock, flags);
399 ret = irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask, force);
400 raw_spin_unlock_irqrestore(&desc->lock, flags);
404 int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
407 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
411 desc->affinity_hint = m;
412 irq_put_desc_unlock(desc, flags);
413 /* set the initial affinity to prevent every interrupt being on CPU0 */
415 __irq_set_affinity(irq, m, false);
418 EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
420 static void irq_affinity_notify(struct work_struct *work)
422 struct irq_affinity_notify *notify =
423 container_of(work, struct irq_affinity_notify, work);
424 struct irq_desc *desc = irq_to_desc(notify->irq);
425 cpumask_var_t cpumask;
428 if (!desc || !alloc_cpumask_var(&cpumask, GFP_KERNEL))
431 raw_spin_lock_irqsave(&desc->lock, flags);
432 if (irq_move_pending(&desc->irq_data))
433 irq_get_pending(cpumask, desc);
435 cpumask_copy(cpumask, desc->irq_common_data.affinity);
436 raw_spin_unlock_irqrestore(&desc->lock, flags);
438 notify->notify(notify, cpumask);
440 free_cpumask_var(cpumask);
442 kref_put(¬ify->kref, notify->release);
446 * irq_set_affinity_notifier - control notification of IRQ affinity changes
447 * @irq: Interrupt for which to enable/disable notification
448 * @notify: Context for notification, or %NULL to disable
449 * notification. Function pointers must be initialised;
450 * the other fields will be initialised by this function.
452 * Must be called in process context. Notification may only be enabled
453 * after the IRQ is allocated and must be disabled before the IRQ is
454 * freed using free_irq().
457 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
459 struct irq_desc *desc = irq_to_desc(irq);
460 struct irq_affinity_notify *old_notify;
463 /* The release function is promised process context */
466 if (!desc || desc->istate & IRQS_NMI)
469 /* Complete initialisation of *notify */
472 kref_init(¬ify->kref);
473 INIT_WORK(¬ify->work, irq_affinity_notify);
476 raw_spin_lock_irqsave(&desc->lock, flags);
477 old_notify = desc->affinity_notify;
478 desc->affinity_notify = notify;
479 raw_spin_unlock_irqrestore(&desc->lock, flags);
482 if (cancel_work_sync(&old_notify->work)) {
483 /* Pending work had a ref, put that one too */
484 kref_put(&old_notify->kref, old_notify->release);
486 kref_put(&old_notify->kref, old_notify->release);
491 EXPORT_SYMBOL_GPL(irq_set_affinity_notifier);
493 #ifndef CONFIG_AUTO_IRQ_AFFINITY
495 * Generic version of the affinity autoselector.
497 int irq_setup_affinity(struct irq_desc *desc)
499 struct cpumask *set = irq_default_affinity;
500 int ret, node = irq_desc_get_node(desc);
501 static DEFINE_RAW_SPINLOCK(mask_lock);
502 static struct cpumask mask;
504 /* Excludes PER_CPU and NO_BALANCE interrupts */
505 if (!__irq_can_set_affinity(desc))
508 raw_spin_lock(&mask_lock);
510 * Preserve the managed affinity setting and a userspace affinity
511 * setup, but make sure that one of the targets is online.
513 if (irqd_affinity_is_managed(&desc->irq_data) ||
514 irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) {
515 if (cpumask_intersects(desc->irq_common_data.affinity,
517 set = desc->irq_common_data.affinity;
519 irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET);
522 cpumask_and(&mask, cpu_online_mask, set);
523 if (cpumask_empty(&mask))
524 cpumask_copy(&mask, cpu_online_mask);
526 if (node != NUMA_NO_NODE) {
527 const struct cpumask *nodemask = cpumask_of_node(node);
529 /* make sure at least one of the cpus in nodemask is online */
530 if (cpumask_intersects(&mask, nodemask))
531 cpumask_and(&mask, &mask, nodemask);
533 ret = irq_do_set_affinity(&desc->irq_data, &mask, false);
534 raw_spin_unlock(&mask_lock);
538 /* Wrapper for ALPHA specific affinity selector magic */
539 int irq_setup_affinity(struct irq_desc *desc)
541 return irq_select_affinity(irq_desc_get_irq(desc));
543 #endif /* CONFIG_AUTO_IRQ_AFFINITY */
544 #endif /* CONFIG_SMP */
548 * irq_set_vcpu_affinity - Set vcpu affinity for the interrupt
549 * @irq: interrupt number to set affinity
550 * @vcpu_info: vCPU specific data or pointer to a percpu array of vCPU
551 * specific data for percpu_devid interrupts
553 * This function uses the vCPU specific data to set the vCPU
554 * affinity for an irq. The vCPU specific data is passed from
555 * outside, such as KVM. One example code path is as below:
556 * KVM -> IOMMU -> irq_set_vcpu_affinity().
558 int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info)
561 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
562 struct irq_data *data;
563 struct irq_chip *chip;
569 data = irq_desc_get_irq_data(desc);
571 chip = irq_data_get_irq_chip(data);
572 if (chip && chip->irq_set_vcpu_affinity)
574 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
575 data = data->parent_data;
582 ret = chip->irq_set_vcpu_affinity(data, vcpu_info);
583 irq_put_desc_unlock(desc, flags);
587 EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity);
589 void __disable_irq(struct irq_desc *desc)
595 static int __disable_irq_nosync(unsigned int irq)
598 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
603 irq_put_desc_busunlock(desc, flags);
608 * disable_irq_nosync - disable an irq without waiting
609 * @irq: Interrupt to disable
611 * Disable the selected interrupt line. Disables and Enables are
613 * Unlike disable_irq(), this function does not ensure existing
614 * instances of the IRQ handler have completed before returning.
616 * This function may be called from IRQ context.
618 void disable_irq_nosync(unsigned int irq)
620 __disable_irq_nosync(irq);
622 EXPORT_SYMBOL(disable_irq_nosync);
625 * disable_irq - disable an irq and wait for completion
626 * @irq: Interrupt to disable
628 * Disable the selected interrupt line. Enables and Disables are
630 * This function waits for any pending IRQ handlers for this interrupt
631 * to complete before returning. If you use this function while
632 * holding a resource the IRQ handler may need you will deadlock.
634 * This function may be called - with care - from IRQ context.
636 void disable_irq(unsigned int irq)
638 if (!__disable_irq_nosync(irq))
639 synchronize_irq(irq);
641 EXPORT_SYMBOL(disable_irq);
644 * disable_hardirq - disables an irq and waits for hardirq completion
645 * @irq: Interrupt to disable
647 * Disable the selected interrupt line. Enables and Disables are
649 * This function waits for any pending hard IRQ handlers for this
650 * interrupt to complete before returning. If you use this function while
651 * holding a resource the hard IRQ handler may need you will deadlock.
653 * When used to optimistically disable an interrupt from atomic context
654 * the return value must be checked.
656 * Returns: false if a threaded handler is active.
658 * This function may be called - with care - from IRQ context.
660 bool disable_hardirq(unsigned int irq)
662 if (!__disable_irq_nosync(irq))
663 return synchronize_hardirq(irq);
667 EXPORT_SYMBOL_GPL(disable_hardirq);
670 * disable_nmi_nosync - disable an nmi without waiting
671 * @irq: Interrupt to disable
673 * Disable the selected interrupt line. Disables and enables are
675 * The interrupt to disable must have been requested through request_nmi.
676 * Unlike disable_nmi(), this function does not ensure existing
677 * instances of the IRQ handler have completed before returning.
679 void disable_nmi_nosync(unsigned int irq)
681 disable_irq_nosync(irq);
684 void __enable_irq(struct irq_desc *desc)
686 switch (desc->depth) {
689 WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n",
690 irq_desc_get_irq(desc));
693 if (desc->istate & IRQS_SUSPENDED)
695 /* Prevent probing on this irq: */
696 irq_settings_set_noprobe(desc);
698 * Call irq_startup() not irq_enable() here because the
699 * interrupt might be marked NOAUTOEN. So irq_startup()
700 * needs to be invoked when it gets enabled the first
701 * time. If it was already started up, then irq_startup()
702 * will invoke irq_enable() under the hood.
704 irq_startup(desc, IRQ_RESEND, IRQ_START_FORCE);
713 * enable_irq - enable handling of an irq
714 * @irq: Interrupt to enable
716 * Undoes the effect of one call to disable_irq(). If this
717 * matches the last disable, processing of interrupts on this
718 * IRQ line is re-enabled.
720 * This function may be called from IRQ context only when
721 * desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
723 void enable_irq(unsigned int irq)
726 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
730 if (WARN(!desc->irq_data.chip,
731 KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
736 irq_put_desc_busunlock(desc, flags);
738 EXPORT_SYMBOL(enable_irq);
741 * enable_nmi - enable handling of an nmi
742 * @irq: Interrupt to enable
744 * The interrupt to enable must have been requested through request_nmi.
745 * Undoes the effect of one call to disable_nmi(). If this
746 * matches the last disable, processing of interrupts on this
747 * IRQ line is re-enabled.
749 void enable_nmi(unsigned int irq)
754 static int set_irq_wake_real(unsigned int irq, unsigned int on)
756 struct irq_desc *desc = irq_to_desc(irq);
759 if (irq_desc_get_chip(desc)->flags & IRQCHIP_SKIP_SET_WAKE)
762 if (desc->irq_data.chip->irq_set_wake)
763 ret = desc->irq_data.chip->irq_set_wake(&desc->irq_data, on);
769 * irq_set_irq_wake - control irq power management wakeup
770 * @irq: interrupt to control
771 * @on: enable/disable power management wakeup
773 * Enable/disable power management wakeup mode, which is
774 * disabled by default. Enables and disables must match,
775 * just as they match for non-wakeup mode support.
777 * Wakeup mode lets this IRQ wake the system from sleep
778 * states like "suspend to RAM".
780 * Note: irq enable/disable state is completely orthogonal
781 * to the enable/disable state of irq wake. An irq can be
782 * disabled with disable_irq() and still wake the system as
783 * long as the irq has wake enabled. If this does not hold,
784 * then the underlying irq chip and the related driver need
785 * to be investigated.
787 int irq_set_irq_wake(unsigned int irq, unsigned int on)
790 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
796 /* Don't use NMIs as wake up interrupts please */
797 if (desc->istate & IRQS_NMI) {
802 /* wakeup-capable irqs can be shared between drivers that
803 * don't need to have the same sleep mode behaviors.
806 if (desc->wake_depth++ == 0) {
807 ret = set_irq_wake_real(irq, on);
809 desc->wake_depth = 0;
811 irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE);
814 if (desc->wake_depth == 0) {
815 WARN(1, "Unbalanced IRQ %d wake disable\n", irq);
816 } else if (--desc->wake_depth == 0) {
817 ret = set_irq_wake_real(irq, on);
819 desc->wake_depth = 1;
821 irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
826 irq_put_desc_busunlock(desc, flags);
829 EXPORT_SYMBOL(irq_set_irq_wake);
832 * Internal function that tells the architecture code whether a
833 * particular irq has been exclusively allocated or is available
836 int can_request_irq(unsigned int irq, unsigned long irqflags)
839 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
845 if (irq_settings_can_request(desc)) {
847 irqflags & desc->action->flags & IRQF_SHARED)
850 irq_put_desc_unlock(desc, flags);
854 int __irq_set_trigger(struct irq_desc *desc, unsigned long flags)
856 struct irq_chip *chip = desc->irq_data.chip;
859 if (!chip || !chip->irq_set_type) {
861 * IRQF_TRIGGER_* but the PIC does not support multiple
864 pr_debug("No set_type function for IRQ %d (%s)\n",
865 irq_desc_get_irq(desc),
866 chip ? (chip->name ? : "unknown") : "unknown");
870 if (chip->flags & IRQCHIP_SET_TYPE_MASKED) {
871 if (!irqd_irq_masked(&desc->irq_data))
873 if (!irqd_irq_disabled(&desc->irq_data))
877 /* Mask all flags except trigger mode */
878 flags &= IRQ_TYPE_SENSE_MASK;
879 ret = chip->irq_set_type(&desc->irq_data, flags);
882 case IRQ_SET_MASK_OK:
883 case IRQ_SET_MASK_OK_DONE:
884 irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK);
885 irqd_set(&desc->irq_data, flags);
888 case IRQ_SET_MASK_OK_NOCOPY:
889 flags = irqd_get_trigger_type(&desc->irq_data);
890 irq_settings_set_trigger_mask(desc, flags);
891 irqd_clear(&desc->irq_data, IRQD_LEVEL);
892 irq_settings_clr_level(desc);
893 if (flags & IRQ_TYPE_LEVEL_MASK) {
894 irq_settings_set_level(desc);
895 irqd_set(&desc->irq_data, IRQD_LEVEL);
901 pr_err("Setting trigger mode %lu for irq %u failed (%pS)\n",
902 flags, irq_desc_get_irq(desc), chip->irq_set_type);
909 #ifdef CONFIG_HARDIRQS_SW_RESEND
910 int irq_set_parent(int irq, int parent_irq)
913 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
918 desc->parent_irq = parent_irq;
920 irq_put_desc_unlock(desc, flags);
923 EXPORT_SYMBOL_GPL(irq_set_parent);
927 * Default primary interrupt handler for threaded interrupts. Is
928 * assigned as primary handler when request_threaded_irq is called
929 * with handler == NULL. Useful for oneshot interrupts.
931 static irqreturn_t irq_default_primary_handler(int irq, void *dev_id)
933 return IRQ_WAKE_THREAD;
937 * Primary handler for nested threaded interrupts. Should never be
940 static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)
942 WARN(1, "Primary handler called for nested irq %d\n", irq);
946 static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id)
948 WARN(1, "Secondary action handler called for irq %d\n", irq);
952 static int irq_wait_for_interrupt(struct irqaction *action)
955 set_current_state(TASK_INTERRUPTIBLE);
957 if (kthread_should_stop()) {
958 /* may need to run one last time */
959 if (test_and_clear_bit(IRQTF_RUNTHREAD,
960 &action->thread_flags)) {
961 __set_current_state(TASK_RUNNING);
964 __set_current_state(TASK_RUNNING);
968 if (test_and_clear_bit(IRQTF_RUNTHREAD,
969 &action->thread_flags)) {
970 __set_current_state(TASK_RUNNING);
978 * Oneshot interrupts keep the irq line masked until the threaded
979 * handler finished. unmask if the interrupt has not been disabled and
982 static void irq_finalize_oneshot(struct irq_desc *desc,
983 struct irqaction *action)
985 if (!(desc->istate & IRQS_ONESHOT) ||
986 action->handler == irq_forced_secondary_handler)
990 raw_spin_lock_irq(&desc->lock);
993 * Implausible though it may be we need to protect us against
994 * the following scenario:
996 * The thread is faster done than the hard interrupt handler
997 * on the other CPU. If we unmask the irq line then the
998 * interrupt can come in again and masks the line, leaves due
999 * to IRQS_INPROGRESS and the irq line is masked forever.
1001 * This also serializes the state of shared oneshot handlers
1002 * versus "desc->threads_oneshot |= action->thread_mask;" in
1003 * irq_wake_thread(). See the comment there which explains the
1006 if (unlikely(irqd_irq_inprogress(&desc->irq_data))) {
1007 raw_spin_unlock_irq(&desc->lock);
1008 chip_bus_sync_unlock(desc);
1014 * Now check again, whether the thread should run. Otherwise
1015 * we would clear the threads_oneshot bit of this thread which
1018 if (test_bit(IRQTF_RUNTHREAD, &action->thread_flags))
1021 desc->threads_oneshot &= ~action->thread_mask;
1023 if (!desc->threads_oneshot && !irqd_irq_disabled(&desc->irq_data) &&
1024 irqd_irq_masked(&desc->irq_data))
1025 unmask_threaded_irq(desc);
1028 raw_spin_unlock_irq(&desc->lock);
1029 chip_bus_sync_unlock(desc);
1034 * Check whether we need to change the affinity of the interrupt thread.
1037 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
1042 if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags))
1046 * In case we are out of memory we set IRQTF_AFFINITY again and
1047 * try again next time
1049 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {
1050 set_bit(IRQTF_AFFINITY, &action->thread_flags);
1054 raw_spin_lock_irq(&desc->lock);
1056 * This code is triggered unconditionally. Check the affinity
1057 * mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
1059 if (cpumask_available(desc->irq_common_data.affinity)) {
1060 const struct cpumask *m;
1062 m = irq_data_get_effective_affinity_mask(&desc->irq_data);
1063 cpumask_copy(mask, m);
1067 raw_spin_unlock_irq(&desc->lock);
1070 set_cpus_allowed_ptr(current, mask);
1071 free_cpumask_var(mask);
1075 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { }
1079 * Interrupts which are not explicitly requested as threaded
1080 * interrupts rely on the implicit bh/preempt disable of the hard irq
1081 * context. So we need to disable bh here to avoid deadlocks and other
1085 irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
1090 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
1091 local_irq_disable();
1092 ret = action->thread_fn(action->irq, action->dev_id);
1093 if (ret == IRQ_HANDLED)
1094 atomic_inc(&desc->threads_handled);
1096 irq_finalize_oneshot(desc, action);
1097 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
1104 * Interrupts explicitly requested as threaded interrupts want to be
1105 * preemtible - many of them need to sleep and wait for slow busses to
1108 static irqreturn_t irq_thread_fn(struct irq_desc *desc,
1109 struct irqaction *action)
1113 ret = action->thread_fn(action->irq, action->dev_id);
1114 if (ret == IRQ_HANDLED)
1115 atomic_inc(&desc->threads_handled);
1117 irq_finalize_oneshot(desc, action);
1121 static void wake_threads_waitq(struct irq_desc *desc)
1123 if (atomic_dec_and_test(&desc->threads_active))
1124 wake_up(&desc->wait_for_threads);
1127 static void irq_thread_dtor(struct callback_head *unused)
1129 struct task_struct *tsk = current;
1130 struct irq_desc *desc;
1131 struct irqaction *action;
1133 if (WARN_ON_ONCE(!(current->flags & PF_EXITING)))
1136 action = kthread_data(tsk);
1138 pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
1139 tsk->comm, tsk->pid, action->irq);
1142 desc = irq_to_desc(action->irq);
1144 * If IRQTF_RUNTHREAD is set, we need to decrement
1145 * desc->threads_active and wake possible waiters.
1147 if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
1148 wake_threads_waitq(desc);
1150 /* Prevent a stale desc->threads_oneshot */
1151 irq_finalize_oneshot(desc, action);
1154 static void irq_wake_secondary(struct irq_desc *desc, struct irqaction *action)
1156 struct irqaction *secondary = action->secondary;
1158 if (WARN_ON_ONCE(!secondary))
1161 raw_spin_lock_irq(&desc->lock);
1162 __irq_wake_thread(desc, secondary);
1163 raw_spin_unlock_irq(&desc->lock);
1167 * Internal function to notify that a interrupt thread is ready.
1169 static void irq_thread_set_ready(struct irq_desc *desc,
1170 struct irqaction *action)
1172 set_bit(IRQTF_READY, &action->thread_flags);
1173 wake_up(&desc->wait_for_threads);
1177 * Internal function to wake up a interrupt thread and wait until it is
1180 static void wake_up_and_wait_for_irq_thread_ready(struct irq_desc *desc,
1181 struct irqaction *action)
1183 if (!action || !action->thread)
1186 wake_up_process(action->thread);
1187 wait_event(desc->wait_for_threads,
1188 test_bit(IRQTF_READY, &action->thread_flags));
1192 * Interrupt handler thread
1194 static int irq_thread(void *data)
1196 struct callback_head on_exit_work;
1197 struct irqaction *action = data;
1198 struct irq_desc *desc = irq_to_desc(action->irq);
1199 irqreturn_t (*handler_fn)(struct irq_desc *desc,
1200 struct irqaction *action);
1202 irq_thread_set_ready(desc, action);
1204 if (force_irqthreads && test_bit(IRQTF_FORCED_THREAD,
1205 &action->thread_flags))
1206 handler_fn = irq_forced_thread_fn;
1208 handler_fn = irq_thread_fn;
1210 init_task_work(&on_exit_work, irq_thread_dtor);
1211 task_work_add(current, &on_exit_work, TWA_NONE);
1213 irq_thread_check_affinity(desc, action);
1215 while (!irq_wait_for_interrupt(action)) {
1216 irqreturn_t action_ret;
1218 irq_thread_check_affinity(desc, action);
1220 action_ret = handler_fn(desc, action);
1221 if (action_ret == IRQ_WAKE_THREAD)
1222 irq_wake_secondary(desc, action);
1224 wake_threads_waitq(desc);
1228 * This is the regular exit path. __free_irq() is stopping the
1229 * thread via kthread_stop() after calling
1230 * synchronize_hardirq(). So neither IRQTF_RUNTHREAD nor the
1231 * oneshot mask bit can be set.
1233 task_work_cancel(current, irq_thread_dtor);
1238 * irq_wake_thread - wake the irq thread for the action identified by dev_id
1239 * @irq: Interrupt line
1240 * @dev_id: Device identity for which the thread should be woken
1243 void irq_wake_thread(unsigned int irq, void *dev_id)
1245 struct irq_desc *desc = irq_to_desc(irq);
1246 struct irqaction *action;
1247 unsigned long flags;
1249 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1252 raw_spin_lock_irqsave(&desc->lock, flags);
1253 for_each_action_of_desc(desc, action) {
1254 if (action->dev_id == dev_id) {
1256 __irq_wake_thread(desc, action);
1260 raw_spin_unlock_irqrestore(&desc->lock, flags);
1262 EXPORT_SYMBOL_GPL(irq_wake_thread);
1264 static int irq_setup_forced_threading(struct irqaction *new)
1266 if (!force_irqthreads)
1268 if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))
1272 * No further action required for interrupts which are requested as
1273 * threaded interrupts already
1275 if (new->handler == irq_default_primary_handler)
1278 new->flags |= IRQF_ONESHOT;
1281 * Handle the case where we have a real primary handler and a
1282 * thread handler. We force thread them as well by creating a
1285 if (new->handler && new->thread_fn) {
1286 /* Allocate the secondary action */
1287 new->secondary = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
1288 if (!new->secondary)
1290 new->secondary->handler = irq_forced_secondary_handler;
1291 new->secondary->thread_fn = new->thread_fn;
1292 new->secondary->dev_id = new->dev_id;
1293 new->secondary->irq = new->irq;
1294 new->secondary->name = new->name;
1296 /* Deal with the primary handler */
1297 set_bit(IRQTF_FORCED_THREAD, &new->thread_flags);
1298 new->thread_fn = new->handler;
1299 new->handler = irq_default_primary_handler;
1303 static int irq_request_resources(struct irq_desc *desc)
1305 struct irq_data *d = &desc->irq_data;
1306 struct irq_chip *c = d->chip;
1308 return c->irq_request_resources ? c->irq_request_resources(d) : 0;
1311 static void irq_release_resources(struct irq_desc *desc)
1313 struct irq_data *d = &desc->irq_data;
1314 struct irq_chip *c = d->chip;
1316 if (c->irq_release_resources)
1317 c->irq_release_resources(d);
1320 static bool irq_supports_nmi(struct irq_desc *desc)
1322 struct irq_data *d = irq_desc_get_irq_data(desc);
1324 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1325 /* Only IRQs directly managed by the root irqchip can be set as NMI */
1329 /* Don't support NMIs for chips behind a slow bus */
1330 if (d->chip->irq_bus_lock || d->chip->irq_bus_sync_unlock)
1333 return d->chip->flags & IRQCHIP_SUPPORTS_NMI;
1336 static int irq_nmi_setup(struct irq_desc *desc)
1338 struct irq_data *d = irq_desc_get_irq_data(desc);
1339 struct irq_chip *c = d->chip;
1341 return c->irq_nmi_setup ? c->irq_nmi_setup(d) : -EINVAL;
1344 static void irq_nmi_teardown(struct irq_desc *desc)
1346 struct irq_data *d = irq_desc_get_irq_data(desc);
1347 struct irq_chip *c = d->chip;
1349 if (c->irq_nmi_teardown)
1350 c->irq_nmi_teardown(d);
1354 setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
1356 struct task_struct *t;
1359 t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
1362 t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq,
1372 * We keep the reference to the task struct even if
1373 * the thread dies to avoid that the interrupt code
1374 * references an already freed task_struct.
1376 new->thread = get_task_struct(t);
1378 * Tell the thread to set its affinity. This is
1379 * important for shared interrupt handlers as we do
1380 * not invoke setup_affinity() for the secondary
1381 * handlers as everything is already set up. Even for
1382 * interrupts marked with IRQF_NO_BALANCE this is
1383 * correct as we want the thread to move to the cpu(s)
1384 * on which the requesting code placed the interrupt.
1386 set_bit(IRQTF_AFFINITY, &new->thread_flags);
1391 * Internal function to register an irqaction - typically used to
1392 * allocate special interrupts that are part of the architecture.
1396 * desc->request_mutex Provides serialization against a concurrent free_irq()
1397 * chip_bus_lock Provides serialization for slow bus operations
1398 * desc->lock Provides serialization against hard interrupts
1400 * chip_bus_lock and desc->lock are sufficient for all other management and
1401 * interrupt related functions. desc->request_mutex solely serializes
1402 * request/free_irq().
1405 __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
1407 struct irqaction *old, **old_ptr;
1408 unsigned long flags, thread_mask = 0;
1409 int ret, nested, shared = 0;
1414 if (desc->irq_data.chip == &no_irq_chip)
1416 if (!try_module_get(desc->owner))
1422 * If the trigger type is not specified by the caller,
1423 * then use the default for this interrupt.
1425 if (!(new->flags & IRQF_TRIGGER_MASK))
1426 new->flags |= irqd_get_trigger_type(&desc->irq_data);
1429 * Check whether the interrupt nests into another interrupt
1432 nested = irq_settings_is_nested_thread(desc);
1434 if (!new->thread_fn) {
1439 * Replace the primary handler which was provided from
1440 * the driver for non nested interrupt handling by the
1441 * dummy function which warns when called.
1443 new->handler = irq_nested_primary_handler;
1445 if (irq_settings_can_thread(desc)) {
1446 ret = irq_setup_forced_threading(new);
1453 * Create a handler thread when a thread function is supplied
1454 * and the interrupt does not nest into another interrupt
1457 if (new->thread_fn && !nested) {
1458 ret = setup_irq_thread(new, irq, false);
1461 if (new->secondary) {
1462 ret = setup_irq_thread(new->secondary, irq, true);
1469 * Drivers are often written to work w/o knowledge about the
1470 * underlying irq chip implementation, so a request for a
1471 * threaded irq without a primary hard irq context handler
1472 * requires the ONESHOT flag to be set. Some irq chips like
1473 * MSI based interrupts are per se one shot safe. Check the
1474 * chip flags, so we can avoid the unmask dance at the end of
1475 * the threaded handler for those.
1477 if (desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)
1478 new->flags &= ~IRQF_ONESHOT;
1481 * Protects against a concurrent __free_irq() call which might wait
1482 * for synchronize_hardirq() to complete without holding the optional
1483 * chip bus lock and desc->lock. Also protects against handing out
1484 * a recycled oneshot thread_mask bit while it's still in use by
1485 * its previous owner.
1487 mutex_lock(&desc->request_mutex);
1490 * Acquire bus lock as the irq_request_resources() callback below
1491 * might rely on the serialization or the magic power management
1492 * functions which are abusing the irq_bus_lock() callback,
1494 chip_bus_lock(desc);
1496 /* First installed action requests resources. */
1497 if (!desc->action) {
1498 ret = irq_request_resources(desc);
1500 pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
1501 new->name, irq, desc->irq_data.chip->name);
1502 goto out_bus_unlock;
1507 * The following block of code has to be executed atomically
1508 * protected against a concurrent interrupt and any of the other
1509 * management calls which are not serialized via
1510 * desc->request_mutex or the optional bus lock.
1512 raw_spin_lock_irqsave(&desc->lock, flags);
1513 old_ptr = &desc->action;
1517 * Can't share interrupts unless both agree to and are
1518 * the same type (level, edge, polarity). So both flag
1519 * fields must have IRQF_SHARED set and the bits which
1520 * set the trigger type must match. Also all must
1522 * Interrupt lines used for NMIs cannot be shared.
1524 unsigned int oldtype;
1526 if (desc->istate & IRQS_NMI) {
1527 pr_err("Invalid attempt to share NMI for %s (irq %d) on irqchip %s.\n",
1528 new->name, irq, desc->irq_data.chip->name);
1534 * If nobody did set the configuration before, inherit
1535 * the one provided by the requester.
1537 if (irqd_trigger_type_was_set(&desc->irq_data)) {
1538 oldtype = irqd_get_trigger_type(&desc->irq_data);
1540 oldtype = new->flags & IRQF_TRIGGER_MASK;
1541 irqd_set_trigger_type(&desc->irq_data, oldtype);
1544 if (!((old->flags & new->flags) & IRQF_SHARED) ||
1545 (oldtype != (new->flags & IRQF_TRIGGER_MASK)) ||
1546 ((old->flags ^ new->flags) & IRQF_ONESHOT))
1549 /* All handlers must agree on per-cpuness */
1550 if ((old->flags & IRQF_PERCPU) !=
1551 (new->flags & IRQF_PERCPU))
1554 /* add new interrupt at end of irq queue */
1557 * Or all existing action->thread_mask bits,
1558 * so we can find the next zero bit for this
1561 thread_mask |= old->thread_mask;
1562 old_ptr = &old->next;
1569 * Setup the thread mask for this irqaction for ONESHOT. For
1570 * !ONESHOT irqs the thread mask is 0 so we can avoid a
1571 * conditional in irq_wake_thread().
1573 if (new->flags & IRQF_ONESHOT) {
1575 * Unlikely to have 32 resp 64 irqs sharing one line,
1578 if (thread_mask == ~0UL) {
1583 * The thread_mask for the action is or'ed to
1584 * desc->thread_active to indicate that the
1585 * IRQF_ONESHOT thread handler has been woken, but not
1586 * yet finished. The bit is cleared when a thread
1587 * completes. When all threads of a shared interrupt
1588 * line have completed desc->threads_active becomes
1589 * zero and the interrupt line is unmasked. See
1590 * handle.c:irq_wake_thread() for further information.
1592 * If no thread is woken by primary (hard irq context)
1593 * interrupt handlers, then desc->threads_active is
1594 * also checked for zero to unmask the irq line in the
1595 * affected hard irq flow handlers
1596 * (handle_[fasteoi|level]_irq).
1598 * The new action gets the first zero bit of
1599 * thread_mask assigned. See the loop above which or's
1600 * all existing action->thread_mask bits.
1602 new->thread_mask = 1UL << ffz(thread_mask);
1604 } else if (new->handler == irq_default_primary_handler &&
1605 !(desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)) {
1607 * The interrupt was requested with handler = NULL, so
1608 * we use the default primary handler for it. But it
1609 * does not have the oneshot flag set. In combination
1610 * with level interrupts this is deadly, because the
1611 * default primary handler just wakes the thread, then
1612 * the irq lines is reenabled, but the device still
1613 * has the level irq asserted. Rinse and repeat....
1615 * While this works for edge type interrupts, we play
1616 * it safe and reject unconditionally because we can't
1617 * say for sure which type this interrupt really
1618 * has. The type flags are unreliable as the
1619 * underlying chip implementation can override them.
1621 pr_err("Threaded irq requested with handler=NULL and !ONESHOT for %s (irq %d)\n",
1628 /* Setup the type (level, edge polarity) if configured: */
1629 if (new->flags & IRQF_TRIGGER_MASK) {
1630 ret = __irq_set_trigger(desc,
1631 new->flags & IRQF_TRIGGER_MASK);
1638 * Activate the interrupt. That activation must happen
1639 * independently of IRQ_NOAUTOEN. request_irq() can fail
1640 * and the callers are supposed to handle
1641 * that. enable_irq() of an interrupt requested with
1642 * IRQ_NOAUTOEN is not supposed to fail. The activation
1643 * keeps it in shutdown mode, it merily associates
1644 * resources if necessary and if that's not possible it
1645 * fails. Interrupts which are in managed shutdown mode
1646 * will simply ignore that activation request.
1648 ret = irq_activate(desc);
1652 desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \
1653 IRQS_ONESHOT | IRQS_WAITING);
1654 irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
1656 if (new->flags & IRQF_PERCPU) {
1657 irqd_set(&desc->irq_data, IRQD_PER_CPU);
1658 irq_settings_set_per_cpu(desc);
1661 if (new->flags & IRQF_ONESHOT)
1662 desc->istate |= IRQS_ONESHOT;
1664 /* Exclude IRQ from balancing if requested */
1665 if (new->flags & IRQF_NOBALANCING) {
1666 irq_settings_set_no_balancing(desc);
1667 irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
1670 if (!(new->flags & IRQF_NO_AUTOEN) &&
1671 irq_settings_can_autoenable(desc)) {
1672 irq_startup(desc, IRQ_RESEND, IRQ_START_COND);
1675 * Shared interrupts do not go well with disabling
1676 * auto enable. The sharing interrupt might request
1677 * it while it's still disabled and then wait for
1678 * interrupts forever.
1680 WARN_ON_ONCE(new->flags & IRQF_SHARED);
1681 /* Undo nested disables: */
1685 } else if (new->flags & IRQF_TRIGGER_MASK) {
1686 unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK;
1687 unsigned int omsk = irqd_get_trigger_type(&desc->irq_data);
1690 /* hope the handler works with current trigger mode */
1691 pr_warn("irq %d uses trigger mode %u; requested %u\n",
1697 irq_pm_install_action(desc, new);
1699 /* Reset broken irq detection when installing new handler */
1700 desc->irq_count = 0;
1701 desc->irqs_unhandled = 0;
1704 * Check whether we disabled the irq via the spurious handler
1705 * before. Reenable it and give it another chance.
1707 if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) {
1708 desc->istate &= ~IRQS_SPURIOUS_DISABLED;
1712 raw_spin_unlock_irqrestore(&desc->lock, flags);
1713 chip_bus_sync_unlock(desc);
1714 mutex_unlock(&desc->request_mutex);
1716 irq_setup_timings(desc, new);
1718 wake_up_and_wait_for_irq_thread_ready(desc, new);
1719 wake_up_and_wait_for_irq_thread_ready(desc, new->secondary);
1721 register_irq_proc(irq, desc);
1723 register_handler_proc(irq, new);
1727 if (!(new->flags & IRQF_PROBE_SHARED)) {
1728 pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
1729 irq, new->flags, new->name, old->flags, old->name);
1730 #ifdef CONFIG_DEBUG_SHIRQ
1737 raw_spin_unlock_irqrestore(&desc->lock, flags);
1740 irq_release_resources(desc);
1742 chip_bus_sync_unlock(desc);
1743 mutex_unlock(&desc->request_mutex);
1747 struct task_struct *t = new->thread;
1753 if (new->secondary && new->secondary->thread) {
1754 struct task_struct *t = new->secondary->thread;
1756 new->secondary->thread = NULL;
1761 module_put(desc->owner);
1766 * Internal function to unregister an irqaction - used to free
1767 * regular and special interrupts that are part of the architecture.
1769 static struct irqaction *__free_irq(struct irq_desc *desc, void *dev_id)
1771 unsigned irq = desc->irq_data.irq;
1772 struct irqaction *action, **action_ptr;
1773 unsigned long flags;
1775 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
1777 mutex_lock(&desc->request_mutex);
1778 chip_bus_lock(desc);
1779 raw_spin_lock_irqsave(&desc->lock, flags);
1782 * There can be multiple actions per IRQ descriptor, find the right
1783 * one based on the dev_id:
1785 action_ptr = &desc->action;
1787 action = *action_ptr;
1790 WARN(1, "Trying to free already-free IRQ %d\n", irq);
1791 raw_spin_unlock_irqrestore(&desc->lock, flags);
1792 chip_bus_sync_unlock(desc);
1793 mutex_unlock(&desc->request_mutex);
1797 if (action->dev_id == dev_id)
1799 action_ptr = &action->next;
1802 /* Found it - now remove it from the list of entries: */
1803 *action_ptr = action->next;
1805 irq_pm_remove_action(desc, action);
1807 /* If this was the last handler, shut down the IRQ line: */
1808 if (!desc->action) {
1809 irq_settings_clr_disable_unlazy(desc);
1810 /* Only shutdown. Deactivate after synchronize_hardirq() */
1815 /* make sure affinity_hint is cleaned up */
1816 if (WARN_ON_ONCE(desc->affinity_hint))
1817 desc->affinity_hint = NULL;
1820 raw_spin_unlock_irqrestore(&desc->lock, flags);
1822 * Drop bus_lock here so the changes which were done in the chip
1823 * callbacks above are synced out to the irq chips which hang
1824 * behind a slow bus (I2C, SPI) before calling synchronize_hardirq().
1826 * Aside of that the bus_lock can also be taken from the threaded
1827 * handler in irq_finalize_oneshot() which results in a deadlock
1828 * because kthread_stop() would wait forever for the thread to
1829 * complete, which is blocked on the bus lock.
1831 * The still held desc->request_mutex() protects against a
1832 * concurrent request_irq() of this irq so the release of resources
1833 * and timing data is properly serialized.
1835 chip_bus_sync_unlock(desc);
1837 unregister_handler_proc(irq, action);
1840 * Make sure it's not being used on another CPU and if the chip
1841 * supports it also make sure that there is no (not yet serviced)
1842 * interrupt in flight at the hardware level.
1844 __synchronize_hardirq(desc, true);
1846 #ifdef CONFIG_DEBUG_SHIRQ
1848 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
1849 * event to happen even now it's being freed, so let's make sure that
1850 * is so by doing an extra call to the handler ....
1852 * ( We do this after actually deregistering it, to make sure that a
1853 * 'real' IRQ doesn't run in parallel with our fake. )
1855 if (action->flags & IRQF_SHARED) {
1856 local_irq_save(flags);
1857 action->handler(irq, dev_id);
1858 local_irq_restore(flags);
1863 * The action has already been removed above, but the thread writes
1864 * its oneshot mask bit when it completes. Though request_mutex is
1865 * held across this which prevents __setup_irq() from handing out
1866 * the same bit to a newly requested action.
1868 if (action->thread) {
1869 kthread_stop(action->thread);
1870 put_task_struct(action->thread);
1871 if (action->secondary && action->secondary->thread) {
1872 kthread_stop(action->secondary->thread);
1873 put_task_struct(action->secondary->thread);
1877 /* Last action releases resources */
1878 if (!desc->action) {
1880 * Reacquire bus lock as irq_release_resources() might
1881 * require it to deallocate resources over the slow bus.
1883 chip_bus_lock(desc);
1885 * There is no interrupt on the fly anymore. Deactivate it
1888 raw_spin_lock_irqsave(&desc->lock, flags);
1889 irq_domain_deactivate_irq(&desc->irq_data);
1890 raw_spin_unlock_irqrestore(&desc->lock, flags);
1892 irq_release_resources(desc);
1893 chip_bus_sync_unlock(desc);
1894 irq_remove_timings(desc);
1897 mutex_unlock(&desc->request_mutex);
1899 irq_chip_pm_put(&desc->irq_data);
1900 module_put(desc->owner);
1901 kfree(action->secondary);
1906 * free_irq - free an interrupt allocated with request_irq
1907 * @irq: Interrupt line to free
1908 * @dev_id: Device identity to free
1910 * Remove an interrupt handler. The handler is removed and if the
1911 * interrupt line is no longer in use by any driver it is disabled.
1912 * On a shared IRQ the caller must ensure the interrupt is disabled
1913 * on the card it drives before calling this function. The function
1914 * does not return until any executing interrupts for this IRQ
1917 * This function must not be called from interrupt context.
1919 * Returns the devname argument passed to request_irq.
1921 const void *free_irq(unsigned int irq, void *dev_id)
1923 struct irq_desc *desc = irq_to_desc(irq);
1924 struct irqaction *action;
1925 const char *devname;
1927 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1931 if (WARN_ON(desc->affinity_notify))
1932 desc->affinity_notify = NULL;
1935 action = __free_irq(desc, dev_id);
1940 devname = action->name;
1944 EXPORT_SYMBOL(free_irq);
1946 /* This function must be called with desc->lock held */
1947 static const void *__cleanup_nmi(unsigned int irq, struct irq_desc *desc)
1949 const char *devname = NULL;
1951 desc->istate &= ~IRQS_NMI;
1953 if (!WARN_ON(desc->action == NULL)) {
1954 irq_pm_remove_action(desc, desc->action);
1955 devname = desc->action->name;
1956 unregister_handler_proc(irq, desc->action);
1958 kfree(desc->action);
1959 desc->action = NULL;
1962 irq_settings_clr_disable_unlazy(desc);
1963 irq_shutdown_and_deactivate(desc);
1965 irq_release_resources(desc);
1967 irq_chip_pm_put(&desc->irq_data);
1968 module_put(desc->owner);
1973 const void *free_nmi(unsigned int irq, void *dev_id)
1975 struct irq_desc *desc = irq_to_desc(irq);
1976 unsigned long flags;
1977 const void *devname;
1979 if (!desc || WARN_ON(!(desc->istate & IRQS_NMI)))
1982 if (WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1985 /* NMI still enabled */
1986 if (WARN_ON(desc->depth == 0))
1987 disable_nmi_nosync(irq);
1989 raw_spin_lock_irqsave(&desc->lock, flags);
1991 irq_nmi_teardown(desc);
1992 devname = __cleanup_nmi(irq, desc);
1994 raw_spin_unlock_irqrestore(&desc->lock, flags);
2000 * request_threaded_irq - allocate an interrupt line
2001 * @irq: Interrupt line to allocate
2002 * @handler: Function to be called when the IRQ occurs.
2003 * Primary handler for threaded interrupts
2004 * If NULL and thread_fn != NULL the default
2005 * primary handler is installed
2006 * @thread_fn: Function called from the irq handler thread
2007 * If NULL, no irq thread is created
2008 * @irqflags: Interrupt type flags
2009 * @devname: An ascii name for the claiming device
2010 * @dev_id: A cookie passed back to the handler function
2012 * This call allocates interrupt resources and enables the
2013 * interrupt line and IRQ handling. From the point this
2014 * call is made your handler function may be invoked. Since
2015 * your handler function must clear any interrupt the board
2016 * raises, you must take care both to initialise your hardware
2017 * and to set up the interrupt handler in the right order.
2019 * If you want to set up a threaded irq handler for your device
2020 * then you need to supply @handler and @thread_fn. @handler is
2021 * still called in hard interrupt context and has to check
2022 * whether the interrupt originates from the device. If yes it
2023 * needs to disable the interrupt on the device and return
2024 * IRQ_WAKE_THREAD which will wake up the handler thread and run
2025 * @thread_fn. This split handler design is necessary to support
2026 * shared interrupts.
2028 * Dev_id must be globally unique. Normally the address of the
2029 * device data structure is used as the cookie. Since the handler
2030 * receives this value it makes sense to use it.
2032 * If your interrupt is shared you must pass a non NULL dev_id
2033 * as this is required when freeing the interrupt.
2037 * IRQF_SHARED Interrupt is shared
2038 * IRQF_TRIGGER_* Specify active edge(s) or level
2041 int request_threaded_irq(unsigned int irq, irq_handler_t handler,
2042 irq_handler_t thread_fn, unsigned long irqflags,
2043 const char *devname, void *dev_id)
2045 struct irqaction *action;
2046 struct irq_desc *desc;
2049 if (irq == IRQ_NOTCONNECTED)
2053 * Sanity-check: shared interrupts must pass in a real dev-ID,
2054 * otherwise we'll have trouble later trying to figure out
2055 * which interrupt is which (messes up the interrupt freeing
2058 * Also shared interrupts do not go well with disabling auto enable.
2059 * The sharing interrupt might request it while it's still disabled
2060 * and then wait for interrupts forever.
2062 * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
2063 * it cannot be set along with IRQF_NO_SUSPEND.
2065 if (((irqflags & IRQF_SHARED) && !dev_id) ||
2066 ((irqflags & IRQF_SHARED) && (irqflags & IRQF_NO_AUTOEN)) ||
2067 (!(irqflags & IRQF_SHARED) && (irqflags & IRQF_COND_SUSPEND)) ||
2068 ((irqflags & IRQF_NO_SUSPEND) && (irqflags & IRQF_COND_SUSPEND)))
2071 desc = irq_to_desc(irq);
2075 if (!irq_settings_can_request(desc) ||
2076 WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2082 handler = irq_default_primary_handler;
2085 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2089 action->handler = handler;
2090 action->thread_fn = thread_fn;
2091 action->flags = irqflags;
2092 action->name = devname;
2093 action->dev_id = dev_id;
2095 retval = irq_chip_pm_get(&desc->irq_data);
2101 retval = __setup_irq(irq, desc, action);
2104 irq_chip_pm_put(&desc->irq_data);
2105 kfree(action->secondary);
2109 #ifdef CONFIG_DEBUG_SHIRQ_FIXME
2110 if (!retval && (irqflags & IRQF_SHARED)) {
2112 * It's a shared IRQ -- the driver ought to be prepared for it
2113 * to happen immediately, so let's make sure....
2114 * We disable the irq to make sure that a 'real' IRQ doesn't
2115 * run in parallel with our fake.
2117 unsigned long flags;
2120 local_irq_save(flags);
2122 handler(irq, dev_id);
2124 local_irq_restore(flags);
2130 EXPORT_SYMBOL(request_threaded_irq);
2133 * request_any_context_irq - allocate an interrupt line
2134 * @irq: Interrupt line to allocate
2135 * @handler: Function to be called when the IRQ occurs.
2136 * Threaded handler for threaded interrupts.
2137 * @flags: Interrupt type flags
2138 * @name: An ascii name for the claiming device
2139 * @dev_id: A cookie passed back to the handler function
2141 * This call allocates interrupt resources and enables the
2142 * interrupt line and IRQ handling. It selects either a
2143 * hardirq or threaded handling method depending on the
2146 * On failure, it returns a negative value. On success,
2147 * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
2149 int request_any_context_irq(unsigned int irq, irq_handler_t handler,
2150 unsigned long flags, const char *name, void *dev_id)
2152 struct irq_desc *desc;
2155 if (irq == IRQ_NOTCONNECTED)
2158 desc = irq_to_desc(irq);
2162 if (irq_settings_is_nested_thread(desc)) {
2163 ret = request_threaded_irq(irq, NULL, handler,
2164 flags, name, dev_id);
2165 return !ret ? IRQC_IS_NESTED : ret;
2168 ret = request_irq(irq, handler, flags, name, dev_id);
2169 return !ret ? IRQC_IS_HARDIRQ : ret;
2171 EXPORT_SYMBOL_GPL(request_any_context_irq);
2174 * request_nmi - allocate an interrupt line for NMI delivery
2175 * @irq: Interrupt line to allocate
2176 * @handler: Function to be called when the IRQ occurs.
2177 * Threaded handler for threaded interrupts.
2178 * @irqflags: Interrupt type flags
2179 * @name: An ascii name for the claiming device
2180 * @dev_id: A cookie passed back to the handler function
2182 * This call allocates interrupt resources and enables the
2183 * interrupt line and IRQ handling. It sets up the IRQ line
2184 * to be handled as an NMI.
2186 * An interrupt line delivering NMIs cannot be shared and IRQ handling
2187 * cannot be threaded.
2189 * Interrupt lines requested for NMI delivering must produce per cpu
2190 * interrupts and have auto enabling setting disabled.
2192 * Dev_id must be globally unique. Normally the address of the
2193 * device data structure is used as the cookie. Since the handler
2194 * receives this value it makes sense to use it.
2196 * If the interrupt line cannot be used to deliver NMIs, function
2197 * will fail and return a negative value.
2199 int request_nmi(unsigned int irq, irq_handler_t handler,
2200 unsigned long irqflags, const char *name, void *dev_id)
2202 struct irqaction *action;
2203 struct irq_desc *desc;
2204 unsigned long flags;
2207 if (irq == IRQ_NOTCONNECTED)
2210 /* NMI cannot be shared, used for Polling */
2211 if (irqflags & (IRQF_SHARED | IRQF_COND_SUSPEND | IRQF_IRQPOLL))
2214 if (!(irqflags & IRQF_PERCPU))
2220 desc = irq_to_desc(irq);
2222 if (!desc || (irq_settings_can_autoenable(desc) &&
2223 !(irqflags & IRQF_NO_AUTOEN)) ||
2224 !irq_settings_can_request(desc) ||
2225 WARN_ON(irq_settings_is_per_cpu_devid(desc)) ||
2226 !irq_supports_nmi(desc))
2229 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2233 action->handler = handler;
2234 action->flags = irqflags | IRQF_NO_THREAD | IRQF_NOBALANCING;
2235 action->name = name;
2236 action->dev_id = dev_id;
2238 retval = irq_chip_pm_get(&desc->irq_data);
2242 retval = __setup_irq(irq, desc, action);
2246 raw_spin_lock_irqsave(&desc->lock, flags);
2248 /* Setup NMI state */
2249 desc->istate |= IRQS_NMI;
2250 retval = irq_nmi_setup(desc);
2252 __cleanup_nmi(irq, desc);
2253 raw_spin_unlock_irqrestore(&desc->lock, flags);
2257 raw_spin_unlock_irqrestore(&desc->lock, flags);
2262 irq_chip_pm_put(&desc->irq_data);
2269 void enable_percpu_irq(unsigned int irq, unsigned int type)
2271 unsigned int cpu = smp_processor_id();
2272 unsigned long flags;
2273 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2279 * If the trigger type is not specified by the caller, then
2280 * use the default for this interrupt.
2282 type &= IRQ_TYPE_SENSE_MASK;
2283 if (type == IRQ_TYPE_NONE)
2284 type = irqd_get_trigger_type(&desc->irq_data);
2286 if (type != IRQ_TYPE_NONE) {
2289 ret = __irq_set_trigger(desc, type);
2292 WARN(1, "failed to set type for IRQ%d\n", irq);
2297 irq_percpu_enable(desc, cpu);
2299 irq_put_desc_unlock(desc, flags);
2301 EXPORT_SYMBOL_GPL(enable_percpu_irq);
2303 void enable_percpu_nmi(unsigned int irq, unsigned int type)
2305 enable_percpu_irq(irq, type);
2309 * irq_percpu_is_enabled - Check whether the per cpu irq is enabled
2310 * @irq: Linux irq number to check for
2312 * Must be called from a non migratable context. Returns the enable
2313 * state of a per cpu interrupt on the current cpu.
2315 bool irq_percpu_is_enabled(unsigned int irq)
2317 unsigned int cpu = smp_processor_id();
2318 struct irq_desc *desc;
2319 unsigned long flags;
2322 desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2326 is_enabled = cpumask_test_cpu(cpu, desc->percpu_enabled);
2327 irq_put_desc_unlock(desc, flags);
2331 EXPORT_SYMBOL_GPL(irq_percpu_is_enabled);
2333 void disable_percpu_irq(unsigned int irq)
2335 unsigned int cpu = smp_processor_id();
2336 unsigned long flags;
2337 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2342 irq_percpu_disable(desc, cpu);
2343 irq_put_desc_unlock(desc, flags);
2345 EXPORT_SYMBOL_GPL(disable_percpu_irq);
2347 void disable_percpu_nmi(unsigned int irq)
2349 disable_percpu_irq(irq);
2353 * Internal function to unregister a percpu irqaction.
2355 static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_id)
2357 struct irq_desc *desc = irq_to_desc(irq);
2358 struct irqaction *action;
2359 unsigned long flags;
2361 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
2366 raw_spin_lock_irqsave(&desc->lock, flags);
2368 action = desc->action;
2369 if (!action || action->percpu_dev_id != dev_id) {
2370 WARN(1, "Trying to free already-free IRQ %d\n", irq);
2374 if (!cpumask_empty(desc->percpu_enabled)) {
2375 WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
2376 irq, cpumask_first(desc->percpu_enabled));
2380 /* Found it - now remove it from the list of entries: */
2381 desc->action = NULL;
2383 desc->istate &= ~IRQS_NMI;
2385 raw_spin_unlock_irqrestore(&desc->lock, flags);
2387 unregister_handler_proc(irq, action);
2389 irq_chip_pm_put(&desc->irq_data);
2390 module_put(desc->owner);
2394 raw_spin_unlock_irqrestore(&desc->lock, flags);
2399 * remove_percpu_irq - free a per-cpu interrupt
2400 * @irq: Interrupt line to free
2401 * @act: irqaction for the interrupt
2403 * Used to remove interrupts statically setup by the early boot process.
2405 void remove_percpu_irq(unsigned int irq, struct irqaction *act)
2407 struct irq_desc *desc = irq_to_desc(irq);
2409 if (desc && irq_settings_is_per_cpu_devid(desc))
2410 __free_percpu_irq(irq, act->percpu_dev_id);
2414 * free_percpu_irq - free an interrupt allocated with request_percpu_irq
2415 * @irq: Interrupt line to free
2416 * @dev_id: Device identity to free
2418 * Remove a percpu interrupt handler. The handler is removed, but
2419 * the interrupt line is not disabled. This must be done on each
2420 * CPU before calling this function. The function does not return
2421 * until any executing interrupts for this IRQ have completed.
2423 * This function must not be called from interrupt context.
2425 void free_percpu_irq(unsigned int irq, void __percpu *dev_id)
2427 struct irq_desc *desc = irq_to_desc(irq);
2429 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2432 chip_bus_lock(desc);
2433 kfree(__free_percpu_irq(irq, dev_id));
2434 chip_bus_sync_unlock(desc);
2436 EXPORT_SYMBOL_GPL(free_percpu_irq);
2438 void free_percpu_nmi(unsigned int irq, void __percpu *dev_id)
2440 struct irq_desc *desc = irq_to_desc(irq);
2442 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2445 if (WARN_ON(!(desc->istate & IRQS_NMI)))
2448 kfree(__free_percpu_irq(irq, dev_id));
2452 * setup_percpu_irq - setup a per-cpu interrupt
2453 * @irq: Interrupt line to setup
2454 * @act: irqaction for the interrupt
2456 * Used to statically setup per-cpu interrupts in the early boot process.
2458 int setup_percpu_irq(unsigned int irq, struct irqaction *act)
2460 struct irq_desc *desc = irq_to_desc(irq);
2463 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2466 retval = irq_chip_pm_get(&desc->irq_data);
2470 retval = __setup_irq(irq, desc, act);
2473 irq_chip_pm_put(&desc->irq_data);
2479 * __request_percpu_irq - allocate a percpu interrupt line
2480 * @irq: Interrupt line to allocate
2481 * @handler: Function to be called when the IRQ occurs.
2482 * @flags: Interrupt type flags (IRQF_TIMER only)
2483 * @devname: An ascii name for the claiming device
2484 * @dev_id: A percpu cookie passed back to the handler function
2486 * This call allocates interrupt resources and enables the
2487 * interrupt on the local CPU. If the interrupt is supposed to be
2488 * enabled on other CPUs, it has to be done on each CPU using
2489 * enable_percpu_irq().
2491 * Dev_id must be globally unique. It is a per-cpu variable, and
2492 * the handler gets called with the interrupted CPU's instance of
2495 int __request_percpu_irq(unsigned int irq, irq_handler_t handler,
2496 unsigned long flags, const char *devname,
2497 void __percpu *dev_id)
2499 struct irqaction *action;
2500 struct irq_desc *desc;
2506 desc = irq_to_desc(irq);
2507 if (!desc || !irq_settings_can_request(desc) ||
2508 !irq_settings_is_per_cpu_devid(desc))
2511 if (flags && flags != IRQF_TIMER)
2514 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2518 action->handler = handler;
2519 action->flags = flags | IRQF_PERCPU | IRQF_NO_SUSPEND;
2520 action->name = devname;
2521 action->percpu_dev_id = dev_id;
2523 retval = irq_chip_pm_get(&desc->irq_data);
2529 retval = __setup_irq(irq, desc, action);
2532 irq_chip_pm_put(&desc->irq_data);
2538 EXPORT_SYMBOL_GPL(__request_percpu_irq);
2541 * request_percpu_nmi - allocate a percpu interrupt line for NMI delivery
2542 * @irq: Interrupt line to allocate
2543 * @handler: Function to be called when the IRQ occurs.
2544 * @name: An ascii name for the claiming device
2545 * @dev_id: A percpu cookie passed back to the handler function
2547 * This call allocates interrupt resources for a per CPU NMI. Per CPU NMIs
2548 * have to be setup on each CPU by calling prepare_percpu_nmi() before
2549 * being enabled on the same CPU by using enable_percpu_nmi().
2551 * Dev_id must be globally unique. It is a per-cpu variable, and
2552 * the handler gets called with the interrupted CPU's instance of
2555 * Interrupt lines requested for NMI delivering should have auto enabling
2558 * If the interrupt line cannot be used to deliver NMIs, function
2559 * will fail returning a negative value.
2561 int request_percpu_nmi(unsigned int irq, irq_handler_t handler,
2562 const char *name, void __percpu *dev_id)
2564 struct irqaction *action;
2565 struct irq_desc *desc;
2566 unsigned long flags;
2572 desc = irq_to_desc(irq);
2574 if (!desc || !irq_settings_can_request(desc) ||
2575 !irq_settings_is_per_cpu_devid(desc) ||
2576 irq_settings_can_autoenable(desc) ||
2577 !irq_supports_nmi(desc))
2580 /* The line cannot already be NMI */
2581 if (desc->istate & IRQS_NMI)
2584 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2588 action->handler = handler;
2589 action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND | IRQF_NO_THREAD
2591 action->name = name;
2592 action->percpu_dev_id = dev_id;
2594 retval = irq_chip_pm_get(&desc->irq_data);
2598 retval = __setup_irq(irq, desc, action);
2602 raw_spin_lock_irqsave(&desc->lock, flags);
2603 desc->istate |= IRQS_NMI;
2604 raw_spin_unlock_irqrestore(&desc->lock, flags);
2609 irq_chip_pm_put(&desc->irq_data);
2617 * prepare_percpu_nmi - performs CPU local setup for NMI delivery
2618 * @irq: Interrupt line to prepare for NMI delivery
2620 * This call prepares an interrupt line to deliver NMI on the current CPU,
2621 * before that interrupt line gets enabled with enable_percpu_nmi().
2623 * As a CPU local operation, this should be called from non-preemptible
2626 * If the interrupt line cannot be used to deliver NMIs, function
2627 * will fail returning a negative value.
2629 int prepare_percpu_nmi(unsigned int irq)
2631 unsigned long flags;
2632 struct irq_desc *desc;
2635 WARN_ON(preemptible());
2637 desc = irq_get_desc_lock(irq, &flags,
2638 IRQ_GET_DESC_CHECK_PERCPU);
2642 if (WARN(!(desc->istate & IRQS_NMI),
2643 KERN_ERR "prepare_percpu_nmi called for a non-NMI interrupt: irq %u\n",
2649 ret = irq_nmi_setup(desc);
2651 pr_err("Failed to setup NMI delivery: irq %u\n", irq);
2656 irq_put_desc_unlock(desc, flags);
2661 * teardown_percpu_nmi - undoes NMI setup of IRQ line
2662 * @irq: Interrupt line from which CPU local NMI configuration should be
2665 * This call undoes the setup done by prepare_percpu_nmi().
2667 * IRQ line should not be enabled for the current CPU.
2669 * As a CPU local operation, this should be called from non-preemptible
2672 void teardown_percpu_nmi(unsigned int irq)
2674 unsigned long flags;
2675 struct irq_desc *desc;
2677 WARN_ON(preemptible());
2679 desc = irq_get_desc_lock(irq, &flags,
2680 IRQ_GET_DESC_CHECK_PERCPU);
2684 if (WARN_ON(!(desc->istate & IRQS_NMI)))
2687 irq_nmi_teardown(desc);
2689 irq_put_desc_unlock(desc, flags);
2692 int __irq_get_irqchip_state(struct irq_data *data, enum irqchip_irq_state which,
2695 struct irq_chip *chip;
2699 chip = irq_data_get_irq_chip(data);
2700 if (WARN_ON_ONCE(!chip))
2702 if (chip->irq_get_irqchip_state)
2704 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2705 data = data->parent_data;
2712 err = chip->irq_get_irqchip_state(data, which, state);
2717 * irq_get_irqchip_state - returns the irqchip state of a interrupt.
2718 * @irq: Interrupt line that is forwarded to a VM
2719 * @which: One of IRQCHIP_STATE_* the caller wants to know about
2720 * @state: a pointer to a boolean where the state is to be storeed
2722 * This call snapshots the internal irqchip state of an
2723 * interrupt, returning into @state the bit corresponding to
2726 * This function should be called with preemption disabled if the
2727 * interrupt controller has per-cpu registers.
2729 int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2732 struct irq_desc *desc;
2733 struct irq_data *data;
2734 unsigned long flags;
2737 desc = irq_get_desc_buslock(irq, &flags, 0);
2741 data = irq_desc_get_irq_data(desc);
2743 err = __irq_get_irqchip_state(data, which, state);
2745 irq_put_desc_busunlock(desc, flags);
2748 EXPORT_SYMBOL_GPL(irq_get_irqchip_state);
2751 * irq_set_irqchip_state - set the state of a forwarded interrupt.
2752 * @irq: Interrupt line that is forwarded to a VM
2753 * @which: State to be restored (one of IRQCHIP_STATE_*)
2754 * @val: Value corresponding to @which
2756 * This call sets the internal irqchip state of an interrupt,
2757 * depending on the value of @which.
2759 * This function should be called with preemption disabled if the
2760 * interrupt controller has per-cpu registers.
2762 int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2765 struct irq_desc *desc;
2766 struct irq_data *data;
2767 struct irq_chip *chip;
2768 unsigned long flags;
2771 desc = irq_get_desc_buslock(irq, &flags, 0);
2775 data = irq_desc_get_irq_data(desc);
2778 chip = irq_data_get_irq_chip(data);
2779 if (WARN_ON_ONCE(!chip)) {
2783 if (chip->irq_set_irqchip_state)
2785 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2786 data = data->parent_data;
2793 err = chip->irq_set_irqchip_state(data, which, val);
2796 irq_put_desc_busunlock(desc, flags);
2799 EXPORT_SYMBOL_GPL(irq_set_irqchip_state);