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);
228 if (!chip || !chip->irq_set_affinity)
232 * If this is a managed interrupt and housekeeping is enabled on
233 * it check whether the requested affinity mask intersects with
234 * a housekeeping CPU. If so, then remove the isolated CPUs from
235 * the mask and just keep the housekeeping CPU(s). This prevents
236 * the affinity setter from routing the interrupt to an isolated
237 * CPU to avoid that I/O submitted from a housekeeping CPU causes
238 * interrupts on an isolated one.
240 * If the masks do not intersect or include online CPU(s) then
241 * keep the requested mask. The isolated target CPUs are only
242 * receiving interrupts when the I/O operation was submitted
243 * directly from them.
245 * If all housekeeping CPUs in the affinity mask are offline, the
246 * interrupt will be migrated by the CPU hotplug code once a
247 * housekeeping CPU which belongs to the affinity mask comes
250 if (irqd_affinity_is_managed(data) &&
251 housekeeping_enabled(HK_FLAG_MANAGED_IRQ)) {
252 const struct cpumask *hk_mask, *prog_mask;
254 static DEFINE_RAW_SPINLOCK(tmp_mask_lock);
255 static struct cpumask tmp_mask;
257 hk_mask = housekeeping_cpumask(HK_FLAG_MANAGED_IRQ);
259 raw_spin_lock(&tmp_mask_lock);
260 cpumask_and(&tmp_mask, mask, hk_mask);
261 if (!cpumask_intersects(&tmp_mask, cpu_online_mask))
264 prog_mask = &tmp_mask;
265 ret = chip->irq_set_affinity(data, prog_mask, force);
266 raw_spin_unlock(&tmp_mask_lock);
268 ret = chip->irq_set_affinity(data, mask, force);
271 case IRQ_SET_MASK_OK:
272 case IRQ_SET_MASK_OK_DONE:
273 cpumask_copy(desc->irq_common_data.affinity, mask);
275 case IRQ_SET_MASK_OK_NOCOPY:
276 irq_validate_effective_affinity(data);
277 irq_set_thread_affinity(desc);
284 #ifdef CONFIG_GENERIC_PENDING_IRQ
285 static inline int irq_set_affinity_pending(struct irq_data *data,
286 const struct cpumask *dest)
288 struct irq_desc *desc = irq_data_to_desc(data);
290 irqd_set_move_pending(data);
291 irq_copy_pending(desc, dest);
295 static inline int irq_set_affinity_pending(struct irq_data *data,
296 const struct cpumask *dest)
302 static int irq_try_set_affinity(struct irq_data *data,
303 const struct cpumask *dest, bool force)
305 int ret = irq_do_set_affinity(data, dest, force);
308 * In case that the underlying vector management is busy and the
309 * architecture supports the generic pending mechanism then utilize
310 * this to avoid returning an error to user space.
312 if (ret == -EBUSY && !force)
313 ret = irq_set_affinity_pending(data, dest);
317 static bool irq_set_affinity_deactivated(struct irq_data *data,
318 const struct cpumask *mask, bool force)
320 struct irq_desc *desc = irq_data_to_desc(data);
323 * If the interrupt is not yet activated, just store the affinity
324 * mask and do not call the chip driver at all. On activation the
325 * driver has to make sure anyway that the interrupt is in a
326 * useable state so startup works.
328 if (!IS_ENABLED(CONFIG_IRQ_DOMAIN_HIERARCHY) || irqd_is_activated(data))
331 cpumask_copy(desc->irq_common_data.affinity, mask);
332 irq_init_effective_affinity(data, mask);
333 irqd_set(data, IRQD_AFFINITY_SET);
337 int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
340 struct irq_chip *chip = irq_data_get_irq_chip(data);
341 struct irq_desc *desc = irq_data_to_desc(data);
344 if (!chip || !chip->irq_set_affinity)
347 if (irq_set_affinity_deactivated(data, mask, force))
350 if (irq_can_move_pcntxt(data) && !irqd_is_setaffinity_pending(data)) {
351 ret = irq_try_set_affinity(data, mask, force);
353 irqd_set_move_pending(data);
354 irq_copy_pending(desc, mask);
357 if (desc->affinity_notify) {
358 kref_get(&desc->affinity_notify->kref);
359 if (!schedule_work(&desc->affinity_notify->work)) {
360 /* Work was already scheduled, drop our extra ref */
361 kref_put(&desc->affinity_notify->kref,
362 desc->affinity_notify->release);
365 irqd_set(data, IRQD_AFFINITY_SET);
370 int __irq_set_affinity(unsigned int irq, const struct cpumask *mask, bool force)
372 struct irq_desc *desc = irq_to_desc(irq);
379 raw_spin_lock_irqsave(&desc->lock, flags);
380 ret = irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask, force);
381 raw_spin_unlock_irqrestore(&desc->lock, flags);
385 int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
388 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
392 desc->affinity_hint = m;
393 irq_put_desc_unlock(desc, flags);
394 /* set the initial affinity to prevent every interrupt being on CPU0 */
396 __irq_set_affinity(irq, m, false);
399 EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
401 static void irq_affinity_notify(struct work_struct *work)
403 struct irq_affinity_notify *notify =
404 container_of(work, struct irq_affinity_notify, work);
405 struct irq_desc *desc = irq_to_desc(notify->irq);
406 cpumask_var_t cpumask;
409 if (!desc || !alloc_cpumask_var(&cpumask, GFP_KERNEL))
412 raw_spin_lock_irqsave(&desc->lock, flags);
413 if (irq_move_pending(&desc->irq_data))
414 irq_get_pending(cpumask, desc);
416 cpumask_copy(cpumask, desc->irq_common_data.affinity);
417 raw_spin_unlock_irqrestore(&desc->lock, flags);
419 notify->notify(notify, cpumask);
421 free_cpumask_var(cpumask);
423 kref_put(¬ify->kref, notify->release);
427 * irq_set_affinity_notifier - control notification of IRQ affinity changes
428 * @irq: Interrupt for which to enable/disable notification
429 * @notify: Context for notification, or %NULL to disable
430 * notification. Function pointers must be initialised;
431 * the other fields will be initialised by this function.
433 * Must be called in process context. Notification may only be enabled
434 * after the IRQ is allocated and must be disabled before the IRQ is
435 * freed using free_irq().
438 irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
440 struct irq_desc *desc = irq_to_desc(irq);
441 struct irq_affinity_notify *old_notify;
444 /* The release function is promised process context */
447 if (!desc || desc->istate & IRQS_NMI)
450 /* Complete initialisation of *notify */
453 kref_init(¬ify->kref);
454 INIT_WORK(¬ify->work, irq_affinity_notify);
457 raw_spin_lock_irqsave(&desc->lock, flags);
458 old_notify = desc->affinity_notify;
459 desc->affinity_notify = notify;
460 raw_spin_unlock_irqrestore(&desc->lock, flags);
463 if (cancel_work_sync(&old_notify->work)) {
464 /* Pending work had a ref, put that one too */
465 kref_put(&old_notify->kref, old_notify->release);
467 kref_put(&old_notify->kref, old_notify->release);
472 EXPORT_SYMBOL_GPL(irq_set_affinity_notifier);
474 #ifndef CONFIG_AUTO_IRQ_AFFINITY
476 * Generic version of the affinity autoselector.
478 int irq_setup_affinity(struct irq_desc *desc)
480 struct cpumask *set = irq_default_affinity;
481 int ret, node = irq_desc_get_node(desc);
482 static DEFINE_RAW_SPINLOCK(mask_lock);
483 static struct cpumask mask;
485 /* Excludes PER_CPU and NO_BALANCE interrupts */
486 if (!__irq_can_set_affinity(desc))
489 raw_spin_lock(&mask_lock);
491 * Preserve the managed affinity setting and a userspace affinity
492 * setup, but make sure that one of the targets is online.
494 if (irqd_affinity_is_managed(&desc->irq_data) ||
495 irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) {
496 if (cpumask_intersects(desc->irq_common_data.affinity,
498 set = desc->irq_common_data.affinity;
500 irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET);
503 cpumask_and(&mask, cpu_online_mask, set);
504 if (cpumask_empty(&mask))
505 cpumask_copy(&mask, cpu_online_mask);
507 if (node != NUMA_NO_NODE) {
508 const struct cpumask *nodemask = cpumask_of_node(node);
510 /* make sure at least one of the cpus in nodemask is online */
511 if (cpumask_intersects(&mask, nodemask))
512 cpumask_and(&mask, &mask, nodemask);
514 ret = irq_do_set_affinity(&desc->irq_data, &mask, false);
515 raw_spin_unlock(&mask_lock);
519 /* Wrapper for ALPHA specific affinity selector magic */
520 int irq_setup_affinity(struct irq_desc *desc)
522 return irq_select_affinity(irq_desc_get_irq(desc));
524 #endif /* CONFIG_AUTO_IRQ_AFFINITY */
525 #endif /* CONFIG_SMP */
529 * irq_set_vcpu_affinity - Set vcpu affinity for the interrupt
530 * @irq: interrupt number to set affinity
531 * @vcpu_info: vCPU specific data or pointer to a percpu array of vCPU
532 * specific data for percpu_devid interrupts
534 * This function uses the vCPU specific data to set the vCPU
535 * affinity for an irq. The vCPU specific data is passed from
536 * outside, such as KVM. One example code path is as below:
537 * KVM -> IOMMU -> irq_set_vcpu_affinity().
539 int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info)
542 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
543 struct irq_data *data;
544 struct irq_chip *chip;
550 data = irq_desc_get_irq_data(desc);
552 chip = irq_data_get_irq_chip(data);
553 if (chip && chip->irq_set_vcpu_affinity)
555 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
556 data = data->parent_data;
563 ret = chip->irq_set_vcpu_affinity(data, vcpu_info);
564 irq_put_desc_unlock(desc, flags);
568 EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity);
570 void __disable_irq(struct irq_desc *desc)
576 static int __disable_irq_nosync(unsigned int irq)
579 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
584 irq_put_desc_busunlock(desc, flags);
589 * disable_irq_nosync - disable an irq without waiting
590 * @irq: Interrupt to disable
592 * Disable the selected interrupt line. Disables and Enables are
594 * Unlike disable_irq(), this function does not ensure existing
595 * instances of the IRQ handler have completed before returning.
597 * This function may be called from IRQ context.
599 void disable_irq_nosync(unsigned int irq)
601 __disable_irq_nosync(irq);
603 EXPORT_SYMBOL(disable_irq_nosync);
606 * disable_irq - disable an irq and wait for completion
607 * @irq: Interrupt to disable
609 * Disable the selected interrupt line. Enables and Disables are
611 * This function waits for any pending IRQ handlers for this interrupt
612 * to complete before returning. If you use this function while
613 * holding a resource the IRQ handler may need you will deadlock.
615 * This function may be called - with care - from IRQ context.
617 void disable_irq(unsigned int irq)
619 if (!__disable_irq_nosync(irq))
620 synchronize_irq(irq);
622 EXPORT_SYMBOL(disable_irq);
625 * disable_hardirq - disables an irq and waits for hardirq completion
626 * @irq: Interrupt to disable
628 * Disable the selected interrupt line. Enables and Disables are
630 * This function waits for any pending hard IRQ handlers for this
631 * interrupt to complete before returning. If you use this function while
632 * holding a resource the hard IRQ handler may need you will deadlock.
634 * When used to optimistically disable an interrupt from atomic context
635 * the return value must be checked.
637 * Returns: false if a threaded handler is active.
639 * This function may be called - with care - from IRQ context.
641 bool disable_hardirq(unsigned int irq)
643 if (!__disable_irq_nosync(irq))
644 return synchronize_hardirq(irq);
648 EXPORT_SYMBOL_GPL(disable_hardirq);
651 * disable_nmi_nosync - disable an nmi without waiting
652 * @irq: Interrupt to disable
654 * Disable the selected interrupt line. Disables and enables are
656 * The interrupt to disable must have been requested through request_nmi.
657 * Unlike disable_nmi(), this function does not ensure existing
658 * instances of the IRQ handler have completed before returning.
660 void disable_nmi_nosync(unsigned int irq)
662 disable_irq_nosync(irq);
665 void __enable_irq(struct irq_desc *desc)
667 switch (desc->depth) {
670 WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n",
671 irq_desc_get_irq(desc));
674 if (desc->istate & IRQS_SUSPENDED)
676 /* Prevent probing on this irq: */
677 irq_settings_set_noprobe(desc);
679 * Call irq_startup() not irq_enable() here because the
680 * interrupt might be marked NOAUTOEN. So irq_startup()
681 * needs to be invoked when it gets enabled the first
682 * time. If it was already started up, then irq_startup()
683 * will invoke irq_enable() under the hood.
685 irq_startup(desc, IRQ_RESEND, IRQ_START_FORCE);
694 * enable_irq - enable handling of an irq
695 * @irq: Interrupt to enable
697 * Undoes the effect of one call to disable_irq(). If this
698 * matches the last disable, processing of interrupts on this
699 * IRQ line is re-enabled.
701 * This function may be called from IRQ context only when
702 * desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
704 void enable_irq(unsigned int irq)
707 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
711 if (WARN(!desc->irq_data.chip,
712 KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
717 irq_put_desc_busunlock(desc, flags);
719 EXPORT_SYMBOL(enable_irq);
722 * enable_nmi - enable handling of an nmi
723 * @irq: Interrupt to enable
725 * The interrupt to enable must have been requested through request_nmi.
726 * Undoes the effect of one call to disable_nmi(). If this
727 * matches the last disable, processing of interrupts on this
728 * IRQ line is re-enabled.
730 void enable_nmi(unsigned int irq)
735 static int set_irq_wake_real(unsigned int irq, unsigned int on)
737 struct irq_desc *desc = irq_to_desc(irq);
740 if (irq_desc_get_chip(desc)->flags & IRQCHIP_SKIP_SET_WAKE)
743 if (desc->irq_data.chip->irq_set_wake)
744 ret = desc->irq_data.chip->irq_set_wake(&desc->irq_data, on);
750 * irq_set_irq_wake - control irq power management wakeup
751 * @irq: interrupt to control
752 * @on: enable/disable power management wakeup
754 * Enable/disable power management wakeup mode, which is
755 * disabled by default. Enables and disables must match,
756 * just as they match for non-wakeup mode support.
758 * Wakeup mode lets this IRQ wake the system from sleep
759 * states like "suspend to RAM".
761 * Note: irq enable/disable state is completely orthogonal
762 * to the enable/disable state of irq wake. An irq can be
763 * disabled with disable_irq() and still wake the system as
764 * long as the irq has wake enabled. If this does not hold,
765 * then the underlying irq chip and the related driver need
766 * to be investigated.
768 int irq_set_irq_wake(unsigned int irq, unsigned int on)
771 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
777 /* Don't use NMIs as wake up interrupts please */
778 if (desc->istate & IRQS_NMI) {
783 /* wakeup-capable irqs can be shared between drivers that
784 * don't need to have the same sleep mode behaviors.
787 if (desc->wake_depth++ == 0) {
788 ret = set_irq_wake_real(irq, on);
790 desc->wake_depth = 0;
792 irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE);
795 if (desc->wake_depth == 0) {
796 WARN(1, "Unbalanced IRQ %d wake disable\n", irq);
797 } else if (--desc->wake_depth == 0) {
798 ret = set_irq_wake_real(irq, on);
800 desc->wake_depth = 1;
802 irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
807 irq_put_desc_busunlock(desc, flags);
810 EXPORT_SYMBOL(irq_set_irq_wake);
813 * Internal function that tells the architecture code whether a
814 * particular irq has been exclusively allocated or is available
817 int can_request_irq(unsigned int irq, unsigned long irqflags)
820 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
826 if (irq_settings_can_request(desc)) {
828 irqflags & desc->action->flags & IRQF_SHARED)
831 irq_put_desc_unlock(desc, flags);
835 int __irq_set_trigger(struct irq_desc *desc, unsigned long flags)
837 struct irq_chip *chip = desc->irq_data.chip;
840 if (!chip || !chip->irq_set_type) {
842 * IRQF_TRIGGER_* but the PIC does not support multiple
845 pr_debug("No set_type function for IRQ %d (%s)\n",
846 irq_desc_get_irq(desc),
847 chip ? (chip->name ? : "unknown") : "unknown");
851 if (chip->flags & IRQCHIP_SET_TYPE_MASKED) {
852 if (!irqd_irq_masked(&desc->irq_data))
854 if (!irqd_irq_disabled(&desc->irq_data))
858 /* Mask all flags except trigger mode */
859 flags &= IRQ_TYPE_SENSE_MASK;
860 ret = chip->irq_set_type(&desc->irq_data, flags);
863 case IRQ_SET_MASK_OK:
864 case IRQ_SET_MASK_OK_DONE:
865 irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK);
866 irqd_set(&desc->irq_data, flags);
869 case IRQ_SET_MASK_OK_NOCOPY:
870 flags = irqd_get_trigger_type(&desc->irq_data);
871 irq_settings_set_trigger_mask(desc, flags);
872 irqd_clear(&desc->irq_data, IRQD_LEVEL);
873 irq_settings_clr_level(desc);
874 if (flags & IRQ_TYPE_LEVEL_MASK) {
875 irq_settings_set_level(desc);
876 irqd_set(&desc->irq_data, IRQD_LEVEL);
882 pr_err("Setting trigger mode %lu for irq %u failed (%pS)\n",
883 flags, irq_desc_get_irq(desc), chip->irq_set_type);
890 #ifdef CONFIG_HARDIRQS_SW_RESEND
891 int irq_set_parent(int irq, int parent_irq)
894 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
899 desc->parent_irq = parent_irq;
901 irq_put_desc_unlock(desc, flags);
904 EXPORT_SYMBOL_GPL(irq_set_parent);
908 * Default primary interrupt handler for threaded interrupts. Is
909 * assigned as primary handler when request_threaded_irq is called
910 * with handler == NULL. Useful for oneshot interrupts.
912 static irqreturn_t irq_default_primary_handler(int irq, void *dev_id)
914 return IRQ_WAKE_THREAD;
918 * Primary handler for nested threaded interrupts. Should never be
921 static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)
923 WARN(1, "Primary handler called for nested irq %d\n", irq);
927 static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id)
929 WARN(1, "Secondary action handler called for irq %d\n", irq);
933 static int irq_wait_for_interrupt(struct irqaction *action)
936 set_current_state(TASK_INTERRUPTIBLE);
938 if (kthread_should_stop()) {
939 /* may need to run one last time */
940 if (test_and_clear_bit(IRQTF_RUNTHREAD,
941 &action->thread_flags)) {
942 __set_current_state(TASK_RUNNING);
945 __set_current_state(TASK_RUNNING);
949 if (test_and_clear_bit(IRQTF_RUNTHREAD,
950 &action->thread_flags)) {
951 __set_current_state(TASK_RUNNING);
959 * Oneshot interrupts keep the irq line masked until the threaded
960 * handler finished. unmask if the interrupt has not been disabled and
963 static void irq_finalize_oneshot(struct irq_desc *desc,
964 struct irqaction *action)
966 if (!(desc->istate & IRQS_ONESHOT) ||
967 action->handler == irq_forced_secondary_handler)
971 raw_spin_lock_irq(&desc->lock);
974 * Implausible though it may be we need to protect us against
975 * the following scenario:
977 * The thread is faster done than the hard interrupt handler
978 * on the other CPU. If we unmask the irq line then the
979 * interrupt can come in again and masks the line, leaves due
980 * to IRQS_INPROGRESS and the irq line is masked forever.
982 * This also serializes the state of shared oneshot handlers
983 * versus "desc->threads_onehsot |= action->thread_mask;" in
984 * irq_wake_thread(). See the comment there which explains the
987 if (unlikely(irqd_irq_inprogress(&desc->irq_data))) {
988 raw_spin_unlock_irq(&desc->lock);
989 chip_bus_sync_unlock(desc);
995 * Now check again, whether the thread should run. Otherwise
996 * we would clear the threads_oneshot bit of this thread which
999 if (test_bit(IRQTF_RUNTHREAD, &action->thread_flags))
1002 desc->threads_oneshot &= ~action->thread_mask;
1004 if (!desc->threads_oneshot && !irqd_irq_disabled(&desc->irq_data) &&
1005 irqd_irq_masked(&desc->irq_data))
1006 unmask_threaded_irq(desc);
1009 raw_spin_unlock_irq(&desc->lock);
1010 chip_bus_sync_unlock(desc);
1015 * Check whether we need to change the affinity of the interrupt thread.
1018 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
1023 if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags))
1027 * In case we are out of memory we set IRQTF_AFFINITY again and
1028 * try again next time
1030 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {
1031 set_bit(IRQTF_AFFINITY, &action->thread_flags);
1035 raw_spin_lock_irq(&desc->lock);
1037 * This code is triggered unconditionally. Check the affinity
1038 * mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
1040 if (cpumask_available(desc->irq_common_data.affinity)) {
1041 const struct cpumask *m;
1043 m = irq_data_get_effective_affinity_mask(&desc->irq_data);
1044 cpumask_copy(mask, m);
1048 raw_spin_unlock_irq(&desc->lock);
1051 set_cpus_allowed_ptr(current, mask);
1052 free_cpumask_var(mask);
1056 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { }
1060 * Interrupts which are not explicitly requested as threaded
1061 * interrupts rely on the implicit bh/preempt disable of the hard irq
1062 * context. So we need to disable bh here to avoid deadlocks and other
1066 irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
1071 ret = action->thread_fn(action->irq, action->dev_id);
1072 if (ret == IRQ_HANDLED)
1073 atomic_inc(&desc->threads_handled);
1075 irq_finalize_oneshot(desc, action);
1081 * Interrupts explicitly requested as threaded interrupts want to be
1082 * preemtible - many of them need to sleep and wait for slow busses to
1085 static irqreturn_t irq_thread_fn(struct irq_desc *desc,
1086 struct irqaction *action)
1090 ret = action->thread_fn(action->irq, action->dev_id);
1091 if (ret == IRQ_HANDLED)
1092 atomic_inc(&desc->threads_handled);
1094 irq_finalize_oneshot(desc, action);
1098 static void wake_threads_waitq(struct irq_desc *desc)
1100 if (atomic_dec_and_test(&desc->threads_active))
1101 wake_up(&desc->wait_for_threads);
1104 static void irq_thread_dtor(struct callback_head *unused)
1106 struct task_struct *tsk = current;
1107 struct irq_desc *desc;
1108 struct irqaction *action;
1110 if (WARN_ON_ONCE(!(current->flags & PF_EXITING)))
1113 action = kthread_data(tsk);
1115 pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
1116 tsk->comm, tsk->pid, action->irq);
1119 desc = irq_to_desc(action->irq);
1121 * If IRQTF_RUNTHREAD is set, we need to decrement
1122 * desc->threads_active and wake possible waiters.
1124 if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
1125 wake_threads_waitq(desc);
1127 /* Prevent a stale desc->threads_oneshot */
1128 irq_finalize_oneshot(desc, action);
1131 static void irq_wake_secondary(struct irq_desc *desc, struct irqaction *action)
1133 struct irqaction *secondary = action->secondary;
1135 if (WARN_ON_ONCE(!secondary))
1138 raw_spin_lock_irq(&desc->lock);
1139 __irq_wake_thread(desc, secondary);
1140 raw_spin_unlock_irq(&desc->lock);
1144 * Interrupt handler thread
1146 static int irq_thread(void *data)
1148 struct callback_head on_exit_work;
1149 struct irqaction *action = data;
1150 struct irq_desc *desc = irq_to_desc(action->irq);
1151 irqreturn_t (*handler_fn)(struct irq_desc *desc,
1152 struct irqaction *action);
1154 if (force_irqthreads && test_bit(IRQTF_FORCED_THREAD,
1155 &action->thread_flags))
1156 handler_fn = irq_forced_thread_fn;
1158 handler_fn = irq_thread_fn;
1160 init_task_work(&on_exit_work, irq_thread_dtor);
1161 task_work_add(current, &on_exit_work, false);
1163 irq_thread_check_affinity(desc, action);
1165 while (!irq_wait_for_interrupt(action)) {
1166 irqreturn_t action_ret;
1168 irq_thread_check_affinity(desc, action);
1170 action_ret = handler_fn(desc, action);
1171 if (action_ret == IRQ_WAKE_THREAD)
1172 irq_wake_secondary(desc, action);
1174 wake_threads_waitq(desc);
1178 * This is the regular exit path. __free_irq() is stopping the
1179 * thread via kthread_stop() after calling
1180 * synchronize_hardirq(). So neither IRQTF_RUNTHREAD nor the
1181 * oneshot mask bit can be set.
1183 task_work_cancel(current, irq_thread_dtor);
1188 * irq_wake_thread - wake the irq thread for the action identified by dev_id
1189 * @irq: Interrupt line
1190 * @dev_id: Device identity for which the thread should be woken
1193 void irq_wake_thread(unsigned int irq, void *dev_id)
1195 struct irq_desc *desc = irq_to_desc(irq);
1196 struct irqaction *action;
1197 unsigned long flags;
1199 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1202 raw_spin_lock_irqsave(&desc->lock, flags);
1203 for_each_action_of_desc(desc, action) {
1204 if (action->dev_id == dev_id) {
1206 __irq_wake_thread(desc, action);
1210 raw_spin_unlock_irqrestore(&desc->lock, flags);
1212 EXPORT_SYMBOL_GPL(irq_wake_thread);
1214 static int irq_setup_forced_threading(struct irqaction *new)
1216 if (!force_irqthreads)
1218 if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))
1222 * No further action required for interrupts which are requested as
1223 * threaded interrupts already
1225 if (new->handler == irq_default_primary_handler)
1228 new->flags |= IRQF_ONESHOT;
1231 * Handle the case where we have a real primary handler and a
1232 * thread handler. We force thread them as well by creating a
1235 if (new->handler && new->thread_fn) {
1236 /* Allocate the secondary action */
1237 new->secondary = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
1238 if (!new->secondary)
1240 new->secondary->handler = irq_forced_secondary_handler;
1241 new->secondary->thread_fn = new->thread_fn;
1242 new->secondary->dev_id = new->dev_id;
1243 new->secondary->irq = new->irq;
1244 new->secondary->name = new->name;
1246 /* Deal with the primary handler */
1247 set_bit(IRQTF_FORCED_THREAD, &new->thread_flags);
1248 new->thread_fn = new->handler;
1249 new->handler = irq_default_primary_handler;
1253 static int irq_request_resources(struct irq_desc *desc)
1255 struct irq_data *d = &desc->irq_data;
1256 struct irq_chip *c = d->chip;
1258 return c->irq_request_resources ? c->irq_request_resources(d) : 0;
1261 static void irq_release_resources(struct irq_desc *desc)
1263 struct irq_data *d = &desc->irq_data;
1264 struct irq_chip *c = d->chip;
1266 if (c->irq_release_resources)
1267 c->irq_release_resources(d);
1270 static bool irq_supports_nmi(struct irq_desc *desc)
1272 struct irq_data *d = irq_desc_get_irq_data(desc);
1274 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
1275 /* Only IRQs directly managed by the root irqchip can be set as NMI */
1279 /* Don't support NMIs for chips behind a slow bus */
1280 if (d->chip->irq_bus_lock || d->chip->irq_bus_sync_unlock)
1283 return d->chip->flags & IRQCHIP_SUPPORTS_NMI;
1286 static int irq_nmi_setup(struct irq_desc *desc)
1288 struct irq_data *d = irq_desc_get_irq_data(desc);
1289 struct irq_chip *c = d->chip;
1291 return c->irq_nmi_setup ? c->irq_nmi_setup(d) : -EINVAL;
1294 static void irq_nmi_teardown(struct irq_desc *desc)
1296 struct irq_data *d = irq_desc_get_irq_data(desc);
1297 struct irq_chip *c = d->chip;
1299 if (c->irq_nmi_teardown)
1300 c->irq_nmi_teardown(d);
1304 setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
1306 struct task_struct *t;
1307 struct sched_param param = {
1308 .sched_priority = MAX_USER_RT_PRIO/2,
1312 t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
1315 t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq,
1317 param.sched_priority -= 1;
1323 sched_setscheduler_nocheck(t, SCHED_FIFO, ¶m);
1326 * We keep the reference to the task struct even if
1327 * the thread dies to avoid that the interrupt code
1328 * references an already freed task_struct.
1330 new->thread = get_task_struct(t);
1332 * Tell the thread to set its affinity. This is
1333 * important for shared interrupt handlers as we do
1334 * not invoke setup_affinity() for the secondary
1335 * handlers as everything is already set up. Even for
1336 * interrupts marked with IRQF_NO_BALANCE this is
1337 * correct as we want the thread to move to the cpu(s)
1338 * on which the requesting code placed the interrupt.
1340 set_bit(IRQTF_AFFINITY, &new->thread_flags);
1345 * Internal function to register an irqaction - typically used to
1346 * allocate special interrupts that are part of the architecture.
1350 * desc->request_mutex Provides serialization against a concurrent free_irq()
1351 * chip_bus_lock Provides serialization for slow bus operations
1352 * desc->lock Provides serialization against hard interrupts
1354 * chip_bus_lock and desc->lock are sufficient for all other management and
1355 * interrupt related functions. desc->request_mutex solely serializes
1356 * request/free_irq().
1359 __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
1361 struct irqaction *old, **old_ptr;
1362 unsigned long flags, thread_mask = 0;
1363 int ret, nested, shared = 0;
1368 if (desc->irq_data.chip == &no_irq_chip)
1370 if (!try_module_get(desc->owner))
1376 * If the trigger type is not specified by the caller,
1377 * then use the default for this interrupt.
1379 if (!(new->flags & IRQF_TRIGGER_MASK))
1380 new->flags |= irqd_get_trigger_type(&desc->irq_data);
1383 * Check whether the interrupt nests into another interrupt
1386 nested = irq_settings_is_nested_thread(desc);
1388 if (!new->thread_fn) {
1393 * Replace the primary handler which was provided from
1394 * the driver for non nested interrupt handling by the
1395 * dummy function which warns when called.
1397 new->handler = irq_nested_primary_handler;
1399 if (irq_settings_can_thread(desc)) {
1400 ret = irq_setup_forced_threading(new);
1407 * Create a handler thread when a thread function is supplied
1408 * and the interrupt does not nest into another interrupt
1411 if (new->thread_fn && !nested) {
1412 ret = setup_irq_thread(new, irq, false);
1415 if (new->secondary) {
1416 ret = setup_irq_thread(new->secondary, irq, true);
1423 * Drivers are often written to work w/o knowledge about the
1424 * underlying irq chip implementation, so a request for a
1425 * threaded irq without a primary hard irq context handler
1426 * requires the ONESHOT flag to be set. Some irq chips like
1427 * MSI based interrupts are per se one shot safe. Check the
1428 * chip flags, so we can avoid the unmask dance at the end of
1429 * the threaded handler for those.
1431 if (desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)
1432 new->flags &= ~IRQF_ONESHOT;
1435 * Protects against a concurrent __free_irq() call which might wait
1436 * for synchronize_hardirq() to complete without holding the optional
1437 * chip bus lock and desc->lock. Also protects against handing out
1438 * a recycled oneshot thread_mask bit while it's still in use by
1439 * its previous owner.
1441 mutex_lock(&desc->request_mutex);
1444 * Acquire bus lock as the irq_request_resources() callback below
1445 * might rely on the serialization or the magic power management
1446 * functions which are abusing the irq_bus_lock() callback,
1448 chip_bus_lock(desc);
1450 /* First installed action requests resources. */
1451 if (!desc->action) {
1452 ret = irq_request_resources(desc);
1454 pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
1455 new->name, irq, desc->irq_data.chip->name);
1456 goto out_bus_unlock;
1461 * The following block of code has to be executed atomically
1462 * protected against a concurrent interrupt and any of the other
1463 * management calls which are not serialized via
1464 * desc->request_mutex or the optional bus lock.
1466 raw_spin_lock_irqsave(&desc->lock, flags);
1467 old_ptr = &desc->action;
1471 * Can't share interrupts unless both agree to and are
1472 * the same type (level, edge, polarity). So both flag
1473 * fields must have IRQF_SHARED set and the bits which
1474 * set the trigger type must match. Also all must
1476 * Interrupt lines used for NMIs cannot be shared.
1478 unsigned int oldtype;
1480 if (desc->istate & IRQS_NMI) {
1481 pr_err("Invalid attempt to share NMI for %s (irq %d) on irqchip %s.\n",
1482 new->name, irq, desc->irq_data.chip->name);
1488 * If nobody did set the configuration before, inherit
1489 * the one provided by the requester.
1491 if (irqd_trigger_type_was_set(&desc->irq_data)) {
1492 oldtype = irqd_get_trigger_type(&desc->irq_data);
1494 oldtype = new->flags & IRQF_TRIGGER_MASK;
1495 irqd_set_trigger_type(&desc->irq_data, oldtype);
1498 if (!((old->flags & new->flags) & IRQF_SHARED) ||
1499 (oldtype != (new->flags & IRQF_TRIGGER_MASK)) ||
1500 ((old->flags ^ new->flags) & IRQF_ONESHOT))
1503 /* All handlers must agree on per-cpuness */
1504 if ((old->flags & IRQF_PERCPU) !=
1505 (new->flags & IRQF_PERCPU))
1508 /* add new interrupt at end of irq queue */
1511 * Or all existing action->thread_mask bits,
1512 * so we can find the next zero bit for this
1515 thread_mask |= old->thread_mask;
1516 old_ptr = &old->next;
1523 * Setup the thread mask for this irqaction for ONESHOT. For
1524 * !ONESHOT irqs the thread mask is 0 so we can avoid a
1525 * conditional in irq_wake_thread().
1527 if (new->flags & IRQF_ONESHOT) {
1529 * Unlikely to have 32 resp 64 irqs sharing one line,
1532 if (thread_mask == ~0UL) {
1537 * The thread_mask for the action is or'ed to
1538 * desc->thread_active to indicate that the
1539 * IRQF_ONESHOT thread handler has been woken, but not
1540 * yet finished. The bit is cleared when a thread
1541 * completes. When all threads of a shared interrupt
1542 * line have completed desc->threads_active becomes
1543 * zero and the interrupt line is unmasked. See
1544 * handle.c:irq_wake_thread() for further information.
1546 * If no thread is woken by primary (hard irq context)
1547 * interrupt handlers, then desc->threads_active is
1548 * also checked for zero to unmask the irq line in the
1549 * affected hard irq flow handlers
1550 * (handle_[fasteoi|level]_irq).
1552 * The new action gets the first zero bit of
1553 * thread_mask assigned. See the loop above which or's
1554 * all existing action->thread_mask bits.
1556 new->thread_mask = 1UL << ffz(thread_mask);
1558 } else if (new->handler == irq_default_primary_handler &&
1559 !(desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)) {
1561 * The interrupt was requested with handler = NULL, so
1562 * we use the default primary handler for it. But it
1563 * does not have the oneshot flag set. In combination
1564 * with level interrupts this is deadly, because the
1565 * default primary handler just wakes the thread, then
1566 * the irq lines is reenabled, but the device still
1567 * has the level irq asserted. Rinse and repeat....
1569 * While this works for edge type interrupts, we play
1570 * it safe and reject unconditionally because we can't
1571 * say for sure which type this interrupt really
1572 * has. The type flags are unreliable as the
1573 * underlying chip implementation can override them.
1575 pr_err("Threaded irq requested with handler=NULL and !ONESHOT for %s (irq %d)\n",
1582 init_waitqueue_head(&desc->wait_for_threads);
1584 /* Setup the type (level, edge polarity) if configured: */
1585 if (new->flags & IRQF_TRIGGER_MASK) {
1586 ret = __irq_set_trigger(desc,
1587 new->flags & IRQF_TRIGGER_MASK);
1594 * Activate the interrupt. That activation must happen
1595 * independently of IRQ_NOAUTOEN. request_irq() can fail
1596 * and the callers are supposed to handle
1597 * that. enable_irq() of an interrupt requested with
1598 * IRQ_NOAUTOEN is not supposed to fail. The activation
1599 * keeps it in shutdown mode, it merily associates
1600 * resources if necessary and if that's not possible it
1601 * fails. Interrupts which are in managed shutdown mode
1602 * will simply ignore that activation request.
1604 ret = irq_activate(desc);
1608 desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \
1609 IRQS_ONESHOT | IRQS_WAITING);
1610 irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
1612 if (new->flags & IRQF_PERCPU) {
1613 irqd_set(&desc->irq_data, IRQD_PER_CPU);
1614 irq_settings_set_per_cpu(desc);
1617 if (new->flags & IRQF_ONESHOT)
1618 desc->istate |= IRQS_ONESHOT;
1620 /* Exclude IRQ from balancing if requested */
1621 if (new->flags & IRQF_NOBALANCING) {
1622 irq_settings_set_no_balancing(desc);
1623 irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
1626 if (irq_settings_can_autoenable(desc)) {
1627 irq_startup(desc, IRQ_RESEND, IRQ_START_COND);
1630 * Shared interrupts do not go well with disabling
1631 * auto enable. The sharing interrupt might request
1632 * it while it's still disabled and then wait for
1633 * interrupts forever.
1635 WARN_ON_ONCE(new->flags & IRQF_SHARED);
1636 /* Undo nested disables: */
1640 } else if (new->flags & IRQF_TRIGGER_MASK) {
1641 unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK;
1642 unsigned int omsk = irqd_get_trigger_type(&desc->irq_data);
1645 /* hope the handler works with current trigger mode */
1646 pr_warn("irq %d uses trigger mode %u; requested %u\n",
1652 irq_pm_install_action(desc, new);
1654 /* Reset broken irq detection when installing new handler */
1655 desc->irq_count = 0;
1656 desc->irqs_unhandled = 0;
1659 * Check whether we disabled the irq via the spurious handler
1660 * before. Reenable it and give it another chance.
1662 if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) {
1663 desc->istate &= ~IRQS_SPURIOUS_DISABLED;
1667 raw_spin_unlock_irqrestore(&desc->lock, flags);
1668 chip_bus_sync_unlock(desc);
1669 mutex_unlock(&desc->request_mutex);
1671 irq_setup_timings(desc, new);
1674 * Strictly no need to wake it up, but hung_task complains
1675 * when no hard interrupt wakes the thread up.
1678 wake_up_process(new->thread);
1680 wake_up_process(new->secondary->thread);
1682 register_irq_proc(irq, desc);
1684 register_handler_proc(irq, new);
1688 if (!(new->flags & IRQF_PROBE_SHARED)) {
1689 pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
1690 irq, new->flags, new->name, old->flags, old->name);
1691 #ifdef CONFIG_DEBUG_SHIRQ
1698 raw_spin_unlock_irqrestore(&desc->lock, flags);
1701 irq_release_resources(desc);
1703 chip_bus_sync_unlock(desc);
1704 mutex_unlock(&desc->request_mutex);
1708 struct task_struct *t = new->thread;
1714 if (new->secondary && new->secondary->thread) {
1715 struct task_struct *t = new->secondary->thread;
1717 new->secondary->thread = NULL;
1722 module_put(desc->owner);
1727 * Internal function to unregister an irqaction - used to free
1728 * regular and special interrupts that are part of the architecture.
1730 static struct irqaction *__free_irq(struct irq_desc *desc, void *dev_id)
1732 unsigned irq = desc->irq_data.irq;
1733 struct irqaction *action, **action_ptr;
1734 unsigned long flags;
1736 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
1738 mutex_lock(&desc->request_mutex);
1739 chip_bus_lock(desc);
1740 raw_spin_lock_irqsave(&desc->lock, flags);
1743 * There can be multiple actions per IRQ descriptor, find the right
1744 * one based on the dev_id:
1746 action_ptr = &desc->action;
1748 action = *action_ptr;
1751 WARN(1, "Trying to free already-free IRQ %d\n", irq);
1752 raw_spin_unlock_irqrestore(&desc->lock, flags);
1753 chip_bus_sync_unlock(desc);
1754 mutex_unlock(&desc->request_mutex);
1758 if (action->dev_id == dev_id)
1760 action_ptr = &action->next;
1763 /* Found it - now remove it from the list of entries: */
1764 *action_ptr = action->next;
1766 irq_pm_remove_action(desc, action);
1768 /* If this was the last handler, shut down the IRQ line: */
1769 if (!desc->action) {
1770 irq_settings_clr_disable_unlazy(desc);
1771 /* Only shutdown. Deactivate after synchronize_hardirq() */
1776 /* make sure affinity_hint is cleaned up */
1777 if (WARN_ON_ONCE(desc->affinity_hint))
1778 desc->affinity_hint = NULL;
1781 raw_spin_unlock_irqrestore(&desc->lock, flags);
1783 * Drop bus_lock here so the changes which were done in the chip
1784 * callbacks above are synced out to the irq chips which hang
1785 * behind a slow bus (I2C, SPI) before calling synchronize_hardirq().
1787 * Aside of that the bus_lock can also be taken from the threaded
1788 * handler in irq_finalize_oneshot() which results in a deadlock
1789 * because kthread_stop() would wait forever for the thread to
1790 * complete, which is blocked on the bus lock.
1792 * The still held desc->request_mutex() protects against a
1793 * concurrent request_irq() of this irq so the release of resources
1794 * and timing data is properly serialized.
1796 chip_bus_sync_unlock(desc);
1798 unregister_handler_proc(irq, action);
1801 * Make sure it's not being used on another CPU and if the chip
1802 * supports it also make sure that there is no (not yet serviced)
1803 * interrupt in flight at the hardware level.
1805 __synchronize_hardirq(desc, true);
1807 #ifdef CONFIG_DEBUG_SHIRQ
1809 * It's a shared IRQ -- the driver ought to be prepared for an IRQ
1810 * event to happen even now it's being freed, so let's make sure that
1811 * is so by doing an extra call to the handler ....
1813 * ( We do this after actually deregistering it, to make sure that a
1814 * 'real' IRQ doesn't run in parallel with our fake. )
1816 if (action->flags & IRQF_SHARED) {
1817 local_irq_save(flags);
1818 action->handler(irq, dev_id);
1819 local_irq_restore(flags);
1824 * The action has already been removed above, but the thread writes
1825 * its oneshot mask bit when it completes. Though request_mutex is
1826 * held across this which prevents __setup_irq() from handing out
1827 * the same bit to a newly requested action.
1829 if (action->thread) {
1830 kthread_stop(action->thread);
1831 put_task_struct(action->thread);
1832 if (action->secondary && action->secondary->thread) {
1833 kthread_stop(action->secondary->thread);
1834 put_task_struct(action->secondary->thread);
1838 /* Last action releases resources */
1839 if (!desc->action) {
1841 * Reaquire bus lock as irq_release_resources() might
1842 * require it to deallocate resources over the slow bus.
1844 chip_bus_lock(desc);
1846 * There is no interrupt on the fly anymore. Deactivate it
1849 raw_spin_lock_irqsave(&desc->lock, flags);
1850 irq_domain_deactivate_irq(&desc->irq_data);
1851 raw_spin_unlock_irqrestore(&desc->lock, flags);
1853 irq_release_resources(desc);
1854 chip_bus_sync_unlock(desc);
1855 irq_remove_timings(desc);
1858 mutex_unlock(&desc->request_mutex);
1860 irq_chip_pm_put(&desc->irq_data);
1861 module_put(desc->owner);
1862 kfree(action->secondary);
1867 * free_irq - free an interrupt allocated with request_irq
1868 * @irq: Interrupt line to free
1869 * @dev_id: Device identity to free
1871 * Remove an interrupt handler. The handler is removed and if the
1872 * interrupt line is no longer in use by any driver it is disabled.
1873 * On a shared IRQ the caller must ensure the interrupt is disabled
1874 * on the card it drives before calling this function. The function
1875 * does not return until any executing interrupts for this IRQ
1878 * This function must not be called from interrupt context.
1880 * Returns the devname argument passed to request_irq.
1882 const void *free_irq(unsigned int irq, void *dev_id)
1884 struct irq_desc *desc = irq_to_desc(irq);
1885 struct irqaction *action;
1886 const char *devname;
1888 if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1892 if (WARN_ON(desc->affinity_notify))
1893 desc->affinity_notify = NULL;
1896 action = __free_irq(desc, dev_id);
1901 devname = action->name;
1905 EXPORT_SYMBOL(free_irq);
1907 /* This function must be called with desc->lock held */
1908 static const void *__cleanup_nmi(unsigned int irq, struct irq_desc *desc)
1910 const char *devname = NULL;
1912 desc->istate &= ~IRQS_NMI;
1914 if (!WARN_ON(desc->action == NULL)) {
1915 irq_pm_remove_action(desc, desc->action);
1916 devname = desc->action->name;
1917 unregister_handler_proc(irq, desc->action);
1919 kfree(desc->action);
1920 desc->action = NULL;
1923 irq_settings_clr_disable_unlazy(desc);
1924 irq_shutdown_and_deactivate(desc);
1926 irq_release_resources(desc);
1928 irq_chip_pm_put(&desc->irq_data);
1929 module_put(desc->owner);
1934 const void *free_nmi(unsigned int irq, void *dev_id)
1936 struct irq_desc *desc = irq_to_desc(irq);
1937 unsigned long flags;
1938 const void *devname;
1940 if (!desc || WARN_ON(!(desc->istate & IRQS_NMI)))
1943 if (WARN_ON(irq_settings_is_per_cpu_devid(desc)))
1946 /* NMI still enabled */
1947 if (WARN_ON(desc->depth == 0))
1948 disable_nmi_nosync(irq);
1950 raw_spin_lock_irqsave(&desc->lock, flags);
1952 irq_nmi_teardown(desc);
1953 devname = __cleanup_nmi(irq, desc);
1955 raw_spin_unlock_irqrestore(&desc->lock, flags);
1961 * request_threaded_irq - allocate an interrupt line
1962 * @irq: Interrupt line to allocate
1963 * @handler: Function to be called when the IRQ occurs.
1964 * Primary handler for threaded interrupts
1965 * If NULL and thread_fn != NULL the default
1966 * primary handler is installed
1967 * @thread_fn: Function called from the irq handler thread
1968 * If NULL, no irq thread is created
1969 * @irqflags: Interrupt type flags
1970 * @devname: An ascii name for the claiming device
1971 * @dev_id: A cookie passed back to the handler function
1973 * This call allocates interrupt resources and enables the
1974 * interrupt line and IRQ handling. From the point this
1975 * call is made your handler function may be invoked. Since
1976 * your handler function must clear any interrupt the board
1977 * raises, you must take care both to initialise your hardware
1978 * and to set up the interrupt handler in the right order.
1980 * If you want to set up a threaded irq handler for your device
1981 * then you need to supply @handler and @thread_fn. @handler is
1982 * still called in hard interrupt context and has to check
1983 * whether the interrupt originates from the device. If yes it
1984 * needs to disable the interrupt on the device and return
1985 * IRQ_WAKE_THREAD which will wake up the handler thread and run
1986 * @thread_fn. This split handler design is necessary to support
1987 * shared interrupts.
1989 * Dev_id must be globally unique. Normally the address of the
1990 * device data structure is used as the cookie. Since the handler
1991 * receives this value it makes sense to use it.
1993 * If your interrupt is shared you must pass a non NULL dev_id
1994 * as this is required when freeing the interrupt.
1998 * IRQF_SHARED Interrupt is shared
1999 * IRQF_TRIGGER_* Specify active edge(s) or level
2002 int request_threaded_irq(unsigned int irq, irq_handler_t handler,
2003 irq_handler_t thread_fn, unsigned long irqflags,
2004 const char *devname, void *dev_id)
2006 struct irqaction *action;
2007 struct irq_desc *desc;
2010 if (irq == IRQ_NOTCONNECTED)
2014 * Sanity-check: shared interrupts must pass in a real dev-ID,
2015 * otherwise we'll have trouble later trying to figure out
2016 * which interrupt is which (messes up the interrupt freeing
2019 * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
2020 * it cannot be set along with IRQF_NO_SUSPEND.
2022 if (((irqflags & IRQF_SHARED) && !dev_id) ||
2023 (!(irqflags & IRQF_SHARED) && (irqflags & IRQF_COND_SUSPEND)) ||
2024 ((irqflags & IRQF_NO_SUSPEND) && (irqflags & IRQF_COND_SUSPEND)))
2027 desc = irq_to_desc(irq);
2031 if (!irq_settings_can_request(desc) ||
2032 WARN_ON(irq_settings_is_per_cpu_devid(desc)))
2038 handler = irq_default_primary_handler;
2041 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2045 action->handler = handler;
2046 action->thread_fn = thread_fn;
2047 action->flags = irqflags;
2048 action->name = devname;
2049 action->dev_id = dev_id;
2051 retval = irq_chip_pm_get(&desc->irq_data);
2057 retval = __setup_irq(irq, desc, action);
2060 irq_chip_pm_put(&desc->irq_data);
2061 kfree(action->secondary);
2065 #ifdef CONFIG_DEBUG_SHIRQ_FIXME
2066 if (!retval && (irqflags & IRQF_SHARED)) {
2068 * It's a shared IRQ -- the driver ought to be prepared for it
2069 * to happen immediately, so let's make sure....
2070 * We disable the irq to make sure that a 'real' IRQ doesn't
2071 * run in parallel with our fake.
2073 unsigned long flags;
2076 local_irq_save(flags);
2078 handler(irq, dev_id);
2080 local_irq_restore(flags);
2086 EXPORT_SYMBOL(request_threaded_irq);
2089 * request_any_context_irq - allocate an interrupt line
2090 * @irq: Interrupt line to allocate
2091 * @handler: Function to be called when the IRQ occurs.
2092 * Threaded handler for threaded interrupts.
2093 * @flags: Interrupt type flags
2094 * @name: An ascii name for the claiming device
2095 * @dev_id: A cookie passed back to the handler function
2097 * This call allocates interrupt resources and enables the
2098 * interrupt line and IRQ handling. It selects either a
2099 * hardirq or threaded handling method depending on the
2102 * On failure, it returns a negative value. On success,
2103 * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
2105 int request_any_context_irq(unsigned int irq, irq_handler_t handler,
2106 unsigned long flags, const char *name, void *dev_id)
2108 struct irq_desc *desc;
2111 if (irq == IRQ_NOTCONNECTED)
2114 desc = irq_to_desc(irq);
2118 if (irq_settings_is_nested_thread(desc)) {
2119 ret = request_threaded_irq(irq, NULL, handler,
2120 flags, name, dev_id);
2121 return !ret ? IRQC_IS_NESTED : ret;
2124 ret = request_irq(irq, handler, flags, name, dev_id);
2125 return !ret ? IRQC_IS_HARDIRQ : ret;
2127 EXPORT_SYMBOL_GPL(request_any_context_irq);
2130 * request_nmi - allocate an interrupt line for NMI delivery
2131 * @irq: Interrupt line to allocate
2132 * @handler: Function to be called when the IRQ occurs.
2133 * Threaded handler for threaded interrupts.
2134 * @irqflags: Interrupt type flags
2135 * @name: An ascii name for the claiming device
2136 * @dev_id: A cookie passed back to the handler function
2138 * This call allocates interrupt resources and enables the
2139 * interrupt line and IRQ handling. It sets up the IRQ line
2140 * to be handled as an NMI.
2142 * An interrupt line delivering NMIs cannot be shared and IRQ handling
2143 * cannot be threaded.
2145 * Interrupt lines requested for NMI delivering must produce per cpu
2146 * interrupts and have auto enabling setting disabled.
2148 * Dev_id must be globally unique. Normally the address of the
2149 * device data structure is used as the cookie. Since the handler
2150 * receives this value it makes sense to use it.
2152 * If the interrupt line cannot be used to deliver NMIs, function
2153 * will fail and return a negative value.
2155 int request_nmi(unsigned int irq, irq_handler_t handler,
2156 unsigned long irqflags, const char *name, void *dev_id)
2158 struct irqaction *action;
2159 struct irq_desc *desc;
2160 unsigned long flags;
2163 if (irq == IRQ_NOTCONNECTED)
2166 /* NMI cannot be shared, used for Polling */
2167 if (irqflags & (IRQF_SHARED | IRQF_COND_SUSPEND | IRQF_IRQPOLL))
2170 if (!(irqflags & IRQF_PERCPU))
2176 desc = irq_to_desc(irq);
2178 if (!desc || irq_settings_can_autoenable(desc) ||
2179 !irq_settings_can_request(desc) ||
2180 WARN_ON(irq_settings_is_per_cpu_devid(desc)) ||
2181 !irq_supports_nmi(desc))
2184 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2188 action->handler = handler;
2189 action->flags = irqflags | IRQF_NO_THREAD | IRQF_NOBALANCING;
2190 action->name = name;
2191 action->dev_id = dev_id;
2193 retval = irq_chip_pm_get(&desc->irq_data);
2197 retval = __setup_irq(irq, desc, action);
2201 raw_spin_lock_irqsave(&desc->lock, flags);
2203 /* Setup NMI state */
2204 desc->istate |= IRQS_NMI;
2205 retval = irq_nmi_setup(desc);
2207 __cleanup_nmi(irq, desc);
2208 raw_spin_unlock_irqrestore(&desc->lock, flags);
2212 raw_spin_unlock_irqrestore(&desc->lock, flags);
2217 irq_chip_pm_put(&desc->irq_data);
2224 void enable_percpu_irq(unsigned int irq, unsigned int type)
2226 unsigned int cpu = smp_processor_id();
2227 unsigned long flags;
2228 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2234 * If the trigger type is not specified by the caller, then
2235 * use the default for this interrupt.
2237 type &= IRQ_TYPE_SENSE_MASK;
2238 if (type == IRQ_TYPE_NONE)
2239 type = irqd_get_trigger_type(&desc->irq_data);
2241 if (type != IRQ_TYPE_NONE) {
2244 ret = __irq_set_trigger(desc, type);
2247 WARN(1, "failed to set type for IRQ%d\n", irq);
2252 irq_percpu_enable(desc, cpu);
2254 irq_put_desc_unlock(desc, flags);
2256 EXPORT_SYMBOL_GPL(enable_percpu_irq);
2258 void enable_percpu_nmi(unsigned int irq, unsigned int type)
2260 enable_percpu_irq(irq, type);
2264 * irq_percpu_is_enabled - Check whether the per cpu irq is enabled
2265 * @irq: Linux irq number to check for
2267 * Must be called from a non migratable context. Returns the enable
2268 * state of a per cpu interrupt on the current cpu.
2270 bool irq_percpu_is_enabled(unsigned int irq)
2272 unsigned int cpu = smp_processor_id();
2273 struct irq_desc *desc;
2274 unsigned long flags;
2277 desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2281 is_enabled = cpumask_test_cpu(cpu, desc->percpu_enabled);
2282 irq_put_desc_unlock(desc, flags);
2286 EXPORT_SYMBOL_GPL(irq_percpu_is_enabled);
2288 void disable_percpu_irq(unsigned int irq)
2290 unsigned int cpu = smp_processor_id();
2291 unsigned long flags;
2292 struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
2297 irq_percpu_disable(desc, cpu);
2298 irq_put_desc_unlock(desc, flags);
2300 EXPORT_SYMBOL_GPL(disable_percpu_irq);
2302 void disable_percpu_nmi(unsigned int irq)
2304 disable_percpu_irq(irq);
2308 * Internal function to unregister a percpu irqaction.
2310 static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_id)
2312 struct irq_desc *desc = irq_to_desc(irq);
2313 struct irqaction *action;
2314 unsigned long flags;
2316 WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
2321 raw_spin_lock_irqsave(&desc->lock, flags);
2323 action = desc->action;
2324 if (!action || action->percpu_dev_id != dev_id) {
2325 WARN(1, "Trying to free already-free IRQ %d\n", irq);
2329 if (!cpumask_empty(desc->percpu_enabled)) {
2330 WARN(1, "percpu IRQ %d still enabled on CPU%d!\n",
2331 irq, cpumask_first(desc->percpu_enabled));
2335 /* Found it - now remove it from the list of entries: */
2336 desc->action = NULL;
2338 desc->istate &= ~IRQS_NMI;
2340 raw_spin_unlock_irqrestore(&desc->lock, flags);
2342 unregister_handler_proc(irq, action);
2344 irq_chip_pm_put(&desc->irq_data);
2345 module_put(desc->owner);
2349 raw_spin_unlock_irqrestore(&desc->lock, flags);
2354 * remove_percpu_irq - free a per-cpu interrupt
2355 * @irq: Interrupt line to free
2356 * @act: irqaction for the interrupt
2358 * Used to remove interrupts statically setup by the early boot process.
2360 void remove_percpu_irq(unsigned int irq, struct irqaction *act)
2362 struct irq_desc *desc = irq_to_desc(irq);
2364 if (desc && irq_settings_is_per_cpu_devid(desc))
2365 __free_percpu_irq(irq, act->percpu_dev_id);
2369 * free_percpu_irq - free an interrupt allocated with request_percpu_irq
2370 * @irq: Interrupt line to free
2371 * @dev_id: Device identity to free
2373 * Remove a percpu interrupt handler. The handler is removed, but
2374 * the interrupt line is not disabled. This must be done on each
2375 * CPU before calling this function. The function does not return
2376 * until any executing interrupts for this IRQ have completed.
2378 * This function must not be called from interrupt context.
2380 void free_percpu_irq(unsigned int irq, void __percpu *dev_id)
2382 struct irq_desc *desc = irq_to_desc(irq);
2384 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2387 chip_bus_lock(desc);
2388 kfree(__free_percpu_irq(irq, dev_id));
2389 chip_bus_sync_unlock(desc);
2391 EXPORT_SYMBOL_GPL(free_percpu_irq);
2393 void free_percpu_nmi(unsigned int irq, void __percpu *dev_id)
2395 struct irq_desc *desc = irq_to_desc(irq);
2397 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2400 if (WARN_ON(!(desc->istate & IRQS_NMI)))
2403 kfree(__free_percpu_irq(irq, dev_id));
2407 * setup_percpu_irq - setup a per-cpu interrupt
2408 * @irq: Interrupt line to setup
2409 * @act: irqaction for the interrupt
2411 * Used to statically setup per-cpu interrupts in the early boot process.
2413 int setup_percpu_irq(unsigned int irq, struct irqaction *act)
2415 struct irq_desc *desc = irq_to_desc(irq);
2418 if (!desc || !irq_settings_is_per_cpu_devid(desc))
2421 retval = irq_chip_pm_get(&desc->irq_data);
2425 retval = __setup_irq(irq, desc, act);
2428 irq_chip_pm_put(&desc->irq_data);
2434 * __request_percpu_irq - allocate a percpu interrupt line
2435 * @irq: Interrupt line to allocate
2436 * @handler: Function to be called when the IRQ occurs.
2437 * @flags: Interrupt type flags (IRQF_TIMER only)
2438 * @devname: An ascii name for the claiming device
2439 * @dev_id: A percpu cookie passed back to the handler function
2441 * This call allocates interrupt resources and enables the
2442 * interrupt on the local CPU. If the interrupt is supposed to be
2443 * enabled on other CPUs, it has to be done on each CPU using
2444 * enable_percpu_irq().
2446 * Dev_id must be globally unique. It is a per-cpu variable, and
2447 * the handler gets called with the interrupted CPU's instance of
2450 int __request_percpu_irq(unsigned int irq, irq_handler_t handler,
2451 unsigned long flags, const char *devname,
2452 void __percpu *dev_id)
2454 struct irqaction *action;
2455 struct irq_desc *desc;
2461 desc = irq_to_desc(irq);
2462 if (!desc || !irq_settings_can_request(desc) ||
2463 !irq_settings_is_per_cpu_devid(desc))
2466 if (flags && flags != IRQF_TIMER)
2469 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2473 action->handler = handler;
2474 action->flags = flags | IRQF_PERCPU | IRQF_NO_SUSPEND;
2475 action->name = devname;
2476 action->percpu_dev_id = dev_id;
2478 retval = irq_chip_pm_get(&desc->irq_data);
2484 retval = __setup_irq(irq, desc, action);
2487 irq_chip_pm_put(&desc->irq_data);
2493 EXPORT_SYMBOL_GPL(__request_percpu_irq);
2496 * request_percpu_nmi - allocate a percpu interrupt line for NMI delivery
2497 * @irq: Interrupt line to allocate
2498 * @handler: Function to be called when the IRQ occurs.
2499 * @name: An ascii name for the claiming device
2500 * @dev_id: A percpu cookie passed back to the handler function
2502 * This call allocates interrupt resources for a per CPU NMI. Per CPU NMIs
2503 * have to be setup on each CPU by calling prepare_percpu_nmi() before
2504 * being enabled on the same CPU by using enable_percpu_nmi().
2506 * Dev_id must be globally unique. It is a per-cpu variable, and
2507 * the handler gets called with the interrupted CPU's instance of
2510 * Interrupt lines requested for NMI delivering should have auto enabling
2513 * If the interrupt line cannot be used to deliver NMIs, function
2514 * will fail returning a negative value.
2516 int request_percpu_nmi(unsigned int irq, irq_handler_t handler,
2517 const char *name, void __percpu *dev_id)
2519 struct irqaction *action;
2520 struct irq_desc *desc;
2521 unsigned long flags;
2527 desc = irq_to_desc(irq);
2529 if (!desc || !irq_settings_can_request(desc) ||
2530 !irq_settings_is_per_cpu_devid(desc) ||
2531 irq_settings_can_autoenable(desc) ||
2532 !irq_supports_nmi(desc))
2535 /* The line cannot already be NMI */
2536 if (desc->istate & IRQS_NMI)
2539 action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
2543 action->handler = handler;
2544 action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND | IRQF_NO_THREAD
2546 action->name = name;
2547 action->percpu_dev_id = dev_id;
2549 retval = irq_chip_pm_get(&desc->irq_data);
2553 retval = __setup_irq(irq, desc, action);
2557 raw_spin_lock_irqsave(&desc->lock, flags);
2558 desc->istate |= IRQS_NMI;
2559 raw_spin_unlock_irqrestore(&desc->lock, flags);
2564 irq_chip_pm_put(&desc->irq_data);
2572 * prepare_percpu_nmi - performs CPU local setup for NMI delivery
2573 * @irq: Interrupt line to prepare for NMI delivery
2575 * This call prepares an interrupt line to deliver NMI on the current CPU,
2576 * before that interrupt line gets enabled with enable_percpu_nmi().
2578 * As a CPU local operation, this should be called from non-preemptible
2581 * If the interrupt line cannot be used to deliver NMIs, function
2582 * will fail returning a negative value.
2584 int prepare_percpu_nmi(unsigned int irq)
2586 unsigned long flags;
2587 struct irq_desc *desc;
2590 WARN_ON(preemptible());
2592 desc = irq_get_desc_lock(irq, &flags,
2593 IRQ_GET_DESC_CHECK_PERCPU);
2597 if (WARN(!(desc->istate & IRQS_NMI),
2598 KERN_ERR "prepare_percpu_nmi called for a non-NMI interrupt: irq %u\n",
2604 ret = irq_nmi_setup(desc);
2606 pr_err("Failed to setup NMI delivery: irq %u\n", irq);
2611 irq_put_desc_unlock(desc, flags);
2616 * teardown_percpu_nmi - undoes NMI setup of IRQ line
2617 * @irq: Interrupt line from which CPU local NMI configuration should be
2620 * This call undoes the setup done by prepare_percpu_nmi().
2622 * IRQ line should not be enabled for the current CPU.
2624 * As a CPU local operation, this should be called from non-preemptible
2627 void teardown_percpu_nmi(unsigned int irq)
2629 unsigned long flags;
2630 struct irq_desc *desc;
2632 WARN_ON(preemptible());
2634 desc = irq_get_desc_lock(irq, &flags,
2635 IRQ_GET_DESC_CHECK_PERCPU);
2639 if (WARN_ON(!(desc->istate & IRQS_NMI)))
2642 irq_nmi_teardown(desc);
2644 irq_put_desc_unlock(desc, flags);
2647 int __irq_get_irqchip_state(struct irq_data *data, enum irqchip_irq_state which,
2650 struct irq_chip *chip;
2654 chip = irq_data_get_irq_chip(data);
2655 if (WARN_ON_ONCE(!chip))
2657 if (chip->irq_get_irqchip_state)
2659 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2660 data = data->parent_data;
2667 err = chip->irq_get_irqchip_state(data, which, state);
2672 * irq_get_irqchip_state - returns the irqchip state of a interrupt.
2673 * @irq: Interrupt line that is forwarded to a VM
2674 * @which: One of IRQCHIP_STATE_* the caller wants to know about
2675 * @state: a pointer to a boolean where the state is to be storeed
2677 * This call snapshots the internal irqchip state of an
2678 * interrupt, returning into @state the bit corresponding to
2681 * This function should be called with preemption disabled if the
2682 * interrupt controller has per-cpu registers.
2684 int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2687 struct irq_desc *desc;
2688 struct irq_data *data;
2689 unsigned long flags;
2692 desc = irq_get_desc_buslock(irq, &flags, 0);
2696 data = irq_desc_get_irq_data(desc);
2698 err = __irq_get_irqchip_state(data, which, state);
2700 irq_put_desc_busunlock(desc, flags);
2703 EXPORT_SYMBOL_GPL(irq_get_irqchip_state);
2706 * irq_set_irqchip_state - set the state of a forwarded interrupt.
2707 * @irq: Interrupt line that is forwarded to a VM
2708 * @which: State to be restored (one of IRQCHIP_STATE_*)
2709 * @val: Value corresponding to @which
2711 * This call sets the internal irqchip state of an interrupt,
2712 * depending on the value of @which.
2714 * This function should be called with preemption disabled if the
2715 * interrupt controller has per-cpu registers.
2717 int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
2720 struct irq_desc *desc;
2721 struct irq_data *data;
2722 struct irq_chip *chip;
2723 unsigned long flags;
2726 desc = irq_get_desc_buslock(irq, &flags, 0);
2730 data = irq_desc_get_irq_data(desc);
2733 chip = irq_data_get_irq_chip(data);
2734 if (WARN_ON_ONCE(!chip))
2736 if (chip->irq_set_irqchip_state)
2738 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
2739 data = data->parent_data;
2746 err = chip->irq_set_irqchip_state(data, which, val);
2748 irq_put_desc_busunlock(desc, flags);
2751 EXPORT_SYMBOL_GPL(irq_set_irqchip_state);