xref: /openbmc/linux/kernel/irq/chip.c (revision adb57164)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
4  * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
5  *
6  * This file contains the core interrupt handling code, for irq-chip based
7  * architectures. Detailed information is available in
8  * Documentation/core-api/genericirq.rst
9  */
10 
11 #include <linux/irq.h>
12 #include <linux/msi.h>
13 #include <linux/module.h>
14 #include <linux/interrupt.h>
15 #include <linux/kernel_stat.h>
16 #include <linux/irqdomain.h>
17 
18 #include <trace/events/irq.h>
19 
20 #include "internals.h"
21 
22 static irqreturn_t bad_chained_irq(int irq, void *dev_id)
23 {
24 	WARN_ONCE(1, "Chained irq %d should not call an action\n", irq);
25 	return IRQ_NONE;
26 }
27 
28 /*
29  * Chained handlers should never call action on their IRQ. This default
30  * action will emit warning if such thing happens.
31  */
32 struct irqaction chained_action = {
33 	.handler = bad_chained_irq,
34 };
35 
36 /**
37  *	irq_set_chip - set the irq chip for an irq
38  *	@irq:	irq number
39  *	@chip:	pointer to irq chip description structure
40  */
41 int irq_set_chip(unsigned int irq, struct irq_chip *chip)
42 {
43 	unsigned long flags;
44 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
45 
46 	if (!desc)
47 		return -EINVAL;
48 
49 	if (!chip)
50 		chip = &no_irq_chip;
51 
52 	desc->irq_data.chip = chip;
53 	irq_put_desc_unlock(desc, flags);
54 	/*
55 	 * For !CONFIG_SPARSE_IRQ make the irq show up in
56 	 * allocated_irqs.
57 	 */
58 	irq_mark_irq(irq);
59 	return 0;
60 }
61 EXPORT_SYMBOL(irq_set_chip);
62 
63 /**
64  *	irq_set_type - set the irq trigger type for an irq
65  *	@irq:	irq number
66  *	@type:	IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
67  */
68 int irq_set_irq_type(unsigned int irq, unsigned int type)
69 {
70 	unsigned long flags;
71 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
72 	int ret = 0;
73 
74 	if (!desc)
75 		return -EINVAL;
76 
77 	ret = __irq_set_trigger(desc, type);
78 	irq_put_desc_busunlock(desc, flags);
79 	return ret;
80 }
81 EXPORT_SYMBOL(irq_set_irq_type);
82 
83 /**
84  *	irq_set_handler_data - set irq handler data for an irq
85  *	@irq:	Interrupt number
86  *	@data:	Pointer to interrupt specific data
87  *
88  *	Set the hardware irq controller data for an irq
89  */
90 int irq_set_handler_data(unsigned int irq, void *data)
91 {
92 	unsigned long flags;
93 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
94 
95 	if (!desc)
96 		return -EINVAL;
97 	desc->irq_common_data.handler_data = data;
98 	irq_put_desc_unlock(desc, flags);
99 	return 0;
100 }
101 EXPORT_SYMBOL(irq_set_handler_data);
102 
103 /**
104  *	irq_set_msi_desc_off - set MSI descriptor data for an irq at offset
105  *	@irq_base:	Interrupt number base
106  *	@irq_offset:	Interrupt number offset
107  *	@entry:		Pointer to MSI descriptor data
108  *
109  *	Set the MSI descriptor entry for an irq at offset
110  */
111 int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset,
112 			 struct msi_desc *entry)
113 {
114 	unsigned long flags;
115 	struct irq_desc *desc = irq_get_desc_lock(irq_base + irq_offset, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
116 
117 	if (!desc)
118 		return -EINVAL;
119 	desc->irq_common_data.msi_desc = entry;
120 	if (entry && !irq_offset)
121 		entry->irq = irq_base;
122 	irq_put_desc_unlock(desc, flags);
123 	return 0;
124 }
125 
126 /**
127  *	irq_set_msi_desc - set MSI descriptor data for an irq
128  *	@irq:	Interrupt number
129  *	@entry:	Pointer to MSI descriptor data
130  *
131  *	Set the MSI descriptor entry for an irq
132  */
133 int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry)
134 {
135 	return irq_set_msi_desc_off(irq, 0, entry);
136 }
137 
138 /**
139  *	irq_set_chip_data - set irq chip data for an irq
140  *	@irq:	Interrupt number
141  *	@data:	Pointer to chip specific data
142  *
143  *	Set the hardware irq chip data for an irq
144  */
145 int irq_set_chip_data(unsigned int irq, void *data)
146 {
147 	unsigned long flags;
148 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
149 
150 	if (!desc)
151 		return -EINVAL;
152 	desc->irq_data.chip_data = data;
153 	irq_put_desc_unlock(desc, flags);
154 	return 0;
155 }
156 EXPORT_SYMBOL(irq_set_chip_data);
157 
158 struct irq_data *irq_get_irq_data(unsigned int irq)
159 {
160 	struct irq_desc *desc = irq_to_desc(irq);
161 
162 	return desc ? &desc->irq_data : NULL;
163 }
164 EXPORT_SYMBOL_GPL(irq_get_irq_data);
165 
166 static void irq_state_clr_disabled(struct irq_desc *desc)
167 {
168 	irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED);
169 }
170 
171 static void irq_state_clr_masked(struct irq_desc *desc)
172 {
173 	irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED);
174 }
175 
176 static void irq_state_clr_started(struct irq_desc *desc)
177 {
178 	irqd_clear(&desc->irq_data, IRQD_IRQ_STARTED);
179 }
180 
181 static void irq_state_set_started(struct irq_desc *desc)
182 {
183 	irqd_set(&desc->irq_data, IRQD_IRQ_STARTED);
184 }
185 
186 enum {
187 	IRQ_STARTUP_NORMAL,
188 	IRQ_STARTUP_MANAGED,
189 	IRQ_STARTUP_ABORT,
190 };
191 
192 #ifdef CONFIG_SMP
193 static int
194 __irq_startup_managed(struct irq_desc *desc, struct cpumask *aff, bool force)
195 {
196 	struct irq_data *d = irq_desc_get_irq_data(desc);
197 
198 	if (!irqd_affinity_is_managed(d))
199 		return IRQ_STARTUP_NORMAL;
200 
201 	irqd_clr_managed_shutdown(d);
202 
203 	if (cpumask_any_and(aff, cpu_online_mask) >= nr_cpu_ids) {
204 		/*
205 		 * Catch code which fiddles with enable_irq() on a managed
206 		 * and potentially shutdown IRQ. Chained interrupt
207 		 * installment or irq auto probing should not happen on
208 		 * managed irqs either.
209 		 */
210 		if (WARN_ON_ONCE(force))
211 			return IRQ_STARTUP_ABORT;
212 		/*
213 		 * The interrupt was requested, but there is no online CPU
214 		 * in it's affinity mask. Put it into managed shutdown
215 		 * state and let the cpu hotplug mechanism start it up once
216 		 * a CPU in the mask becomes available.
217 		 */
218 		return IRQ_STARTUP_ABORT;
219 	}
220 	/*
221 	 * Managed interrupts have reserved resources, so this should not
222 	 * happen.
223 	 */
224 	if (WARN_ON(irq_domain_activate_irq(d, false)))
225 		return IRQ_STARTUP_ABORT;
226 	return IRQ_STARTUP_MANAGED;
227 }
228 #else
229 static __always_inline int
230 __irq_startup_managed(struct irq_desc *desc, struct cpumask *aff, bool force)
231 {
232 	return IRQ_STARTUP_NORMAL;
233 }
234 #endif
235 
236 static int __irq_startup(struct irq_desc *desc)
237 {
238 	struct irq_data *d = irq_desc_get_irq_data(desc);
239 	int ret = 0;
240 
241 	/* Warn if this interrupt is not activated but try nevertheless */
242 	WARN_ON_ONCE(!irqd_is_activated(d));
243 
244 	if (d->chip->irq_startup) {
245 		ret = d->chip->irq_startup(d);
246 		irq_state_clr_disabled(desc);
247 		irq_state_clr_masked(desc);
248 	} else {
249 		irq_enable(desc);
250 	}
251 	irq_state_set_started(desc);
252 	return ret;
253 }
254 
255 int irq_startup(struct irq_desc *desc, bool resend, bool force)
256 {
257 	struct irq_data *d = irq_desc_get_irq_data(desc);
258 	struct cpumask *aff = irq_data_get_affinity_mask(d);
259 	int ret = 0;
260 
261 	desc->depth = 0;
262 
263 	if (irqd_is_started(d)) {
264 		irq_enable(desc);
265 	} else {
266 		switch (__irq_startup_managed(desc, aff, force)) {
267 		case IRQ_STARTUP_NORMAL:
268 			ret = __irq_startup(desc);
269 			irq_setup_affinity(desc);
270 			break;
271 		case IRQ_STARTUP_MANAGED:
272 			irq_do_set_affinity(d, aff, false);
273 			ret = __irq_startup(desc);
274 			break;
275 		case IRQ_STARTUP_ABORT:
276 			irqd_set_managed_shutdown(d);
277 			return 0;
278 		}
279 	}
280 	if (resend)
281 		check_irq_resend(desc, false);
282 
283 	return ret;
284 }
285 
286 int irq_activate(struct irq_desc *desc)
287 {
288 	struct irq_data *d = irq_desc_get_irq_data(desc);
289 
290 	if (!irqd_affinity_is_managed(d))
291 		return irq_domain_activate_irq(d, false);
292 	return 0;
293 }
294 
295 int irq_activate_and_startup(struct irq_desc *desc, bool resend)
296 {
297 	if (WARN_ON(irq_activate(desc)))
298 		return 0;
299 	return irq_startup(desc, resend, IRQ_START_FORCE);
300 }
301 
302 static void __irq_disable(struct irq_desc *desc, bool mask);
303 
304 void irq_shutdown(struct irq_desc *desc)
305 {
306 	if (irqd_is_started(&desc->irq_data)) {
307 		desc->depth = 1;
308 		if (desc->irq_data.chip->irq_shutdown) {
309 			desc->irq_data.chip->irq_shutdown(&desc->irq_data);
310 			irq_state_set_disabled(desc);
311 			irq_state_set_masked(desc);
312 		} else {
313 			__irq_disable(desc, true);
314 		}
315 		irq_state_clr_started(desc);
316 	}
317 }
318 
319 
320 void irq_shutdown_and_deactivate(struct irq_desc *desc)
321 {
322 	irq_shutdown(desc);
323 	/*
324 	 * This must be called even if the interrupt was never started up,
325 	 * because the activation can happen before the interrupt is
326 	 * available for request/startup. It has it's own state tracking so
327 	 * it's safe to call it unconditionally.
328 	 */
329 	irq_domain_deactivate_irq(&desc->irq_data);
330 }
331 
332 void irq_enable(struct irq_desc *desc)
333 {
334 	if (!irqd_irq_disabled(&desc->irq_data)) {
335 		unmask_irq(desc);
336 	} else {
337 		irq_state_clr_disabled(desc);
338 		if (desc->irq_data.chip->irq_enable) {
339 			desc->irq_data.chip->irq_enable(&desc->irq_data);
340 			irq_state_clr_masked(desc);
341 		} else {
342 			unmask_irq(desc);
343 		}
344 	}
345 }
346 
347 static void __irq_disable(struct irq_desc *desc, bool mask)
348 {
349 	if (irqd_irq_disabled(&desc->irq_data)) {
350 		if (mask)
351 			mask_irq(desc);
352 	} else {
353 		irq_state_set_disabled(desc);
354 		if (desc->irq_data.chip->irq_disable) {
355 			desc->irq_data.chip->irq_disable(&desc->irq_data);
356 			irq_state_set_masked(desc);
357 		} else if (mask) {
358 			mask_irq(desc);
359 		}
360 	}
361 }
362 
363 /**
364  * irq_disable - Mark interrupt disabled
365  * @desc:	irq descriptor which should be disabled
366  *
367  * If the chip does not implement the irq_disable callback, we
368  * use a lazy disable approach. That means we mark the interrupt
369  * disabled, but leave the hardware unmasked. That's an
370  * optimization because we avoid the hardware access for the
371  * common case where no interrupt happens after we marked it
372  * disabled. If an interrupt happens, then the interrupt flow
373  * handler masks the line at the hardware level and marks it
374  * pending.
375  *
376  * If the interrupt chip does not implement the irq_disable callback,
377  * a driver can disable the lazy approach for a particular irq line by
378  * calling 'irq_set_status_flags(irq, IRQ_DISABLE_UNLAZY)'. This can
379  * be used for devices which cannot disable the interrupt at the
380  * device level under certain circumstances and have to use
381  * disable_irq[_nosync] instead.
382  */
383 void irq_disable(struct irq_desc *desc)
384 {
385 	__irq_disable(desc, irq_settings_disable_unlazy(desc));
386 }
387 
388 void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu)
389 {
390 	if (desc->irq_data.chip->irq_enable)
391 		desc->irq_data.chip->irq_enable(&desc->irq_data);
392 	else
393 		desc->irq_data.chip->irq_unmask(&desc->irq_data);
394 	cpumask_set_cpu(cpu, desc->percpu_enabled);
395 }
396 
397 void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu)
398 {
399 	if (desc->irq_data.chip->irq_disable)
400 		desc->irq_data.chip->irq_disable(&desc->irq_data);
401 	else
402 		desc->irq_data.chip->irq_mask(&desc->irq_data);
403 	cpumask_clear_cpu(cpu, desc->percpu_enabled);
404 }
405 
406 static inline void mask_ack_irq(struct irq_desc *desc)
407 {
408 	if (desc->irq_data.chip->irq_mask_ack) {
409 		desc->irq_data.chip->irq_mask_ack(&desc->irq_data);
410 		irq_state_set_masked(desc);
411 	} else {
412 		mask_irq(desc);
413 		if (desc->irq_data.chip->irq_ack)
414 			desc->irq_data.chip->irq_ack(&desc->irq_data);
415 	}
416 }
417 
418 void mask_irq(struct irq_desc *desc)
419 {
420 	if (irqd_irq_masked(&desc->irq_data))
421 		return;
422 
423 	if (desc->irq_data.chip->irq_mask) {
424 		desc->irq_data.chip->irq_mask(&desc->irq_data);
425 		irq_state_set_masked(desc);
426 	}
427 }
428 
429 void unmask_irq(struct irq_desc *desc)
430 {
431 	if (!irqd_irq_masked(&desc->irq_data))
432 		return;
433 
434 	if (desc->irq_data.chip->irq_unmask) {
435 		desc->irq_data.chip->irq_unmask(&desc->irq_data);
436 		irq_state_clr_masked(desc);
437 	}
438 }
439 
440 void unmask_threaded_irq(struct irq_desc *desc)
441 {
442 	struct irq_chip *chip = desc->irq_data.chip;
443 
444 	if (chip->flags & IRQCHIP_EOI_THREADED)
445 		chip->irq_eoi(&desc->irq_data);
446 
447 	unmask_irq(desc);
448 }
449 
450 /*
451  *	handle_nested_irq - Handle a nested irq from a irq thread
452  *	@irq:	the interrupt number
453  *
454  *	Handle interrupts which are nested into a threaded interrupt
455  *	handler. The handler function is called inside the calling
456  *	threads context.
457  */
458 void handle_nested_irq(unsigned int irq)
459 {
460 	struct irq_desc *desc = irq_to_desc(irq);
461 	struct irqaction *action;
462 	irqreturn_t action_ret;
463 
464 	might_sleep();
465 
466 	raw_spin_lock_irq(&desc->lock);
467 
468 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
469 
470 	action = desc->action;
471 	if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) {
472 		desc->istate |= IRQS_PENDING;
473 		goto out_unlock;
474 	}
475 
476 	kstat_incr_irqs_this_cpu(desc);
477 	irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
478 	raw_spin_unlock_irq(&desc->lock);
479 
480 	action_ret = IRQ_NONE;
481 	for_each_action_of_desc(desc, action)
482 		action_ret |= action->thread_fn(action->irq, action->dev_id);
483 
484 	if (!noirqdebug)
485 		note_interrupt(desc, action_ret);
486 
487 	raw_spin_lock_irq(&desc->lock);
488 	irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
489 
490 out_unlock:
491 	raw_spin_unlock_irq(&desc->lock);
492 }
493 EXPORT_SYMBOL_GPL(handle_nested_irq);
494 
495 static bool irq_check_poll(struct irq_desc *desc)
496 {
497 	if (!(desc->istate & IRQS_POLL_INPROGRESS))
498 		return false;
499 	return irq_wait_for_poll(desc);
500 }
501 
502 static bool irq_may_run(struct irq_desc *desc)
503 {
504 	unsigned int mask = IRQD_IRQ_INPROGRESS | IRQD_WAKEUP_ARMED;
505 
506 	/*
507 	 * If the interrupt is not in progress and is not an armed
508 	 * wakeup interrupt, proceed.
509 	 */
510 	if (!irqd_has_set(&desc->irq_data, mask))
511 		return true;
512 
513 	/*
514 	 * If the interrupt is an armed wakeup source, mark it pending
515 	 * and suspended, disable it and notify the pm core about the
516 	 * event.
517 	 */
518 	if (irq_pm_check_wakeup(desc))
519 		return false;
520 
521 	/*
522 	 * Handle a potential concurrent poll on a different core.
523 	 */
524 	return irq_check_poll(desc);
525 }
526 
527 /**
528  *	handle_simple_irq - Simple and software-decoded IRQs.
529  *	@desc:	the interrupt description structure for this irq
530  *
531  *	Simple interrupts are either sent from a demultiplexing interrupt
532  *	handler or come from hardware, where no interrupt hardware control
533  *	is necessary.
534  *
535  *	Note: The caller is expected to handle the ack, clear, mask and
536  *	unmask issues if necessary.
537  */
538 void handle_simple_irq(struct irq_desc *desc)
539 {
540 	raw_spin_lock(&desc->lock);
541 
542 	if (!irq_may_run(desc))
543 		goto out_unlock;
544 
545 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
546 
547 	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
548 		desc->istate |= IRQS_PENDING;
549 		goto out_unlock;
550 	}
551 
552 	kstat_incr_irqs_this_cpu(desc);
553 	handle_irq_event(desc);
554 
555 out_unlock:
556 	raw_spin_unlock(&desc->lock);
557 }
558 EXPORT_SYMBOL_GPL(handle_simple_irq);
559 
560 /**
561  *	handle_untracked_irq - Simple and software-decoded IRQs.
562  *	@desc:	the interrupt description structure for this irq
563  *
564  *	Untracked interrupts are sent from a demultiplexing interrupt
565  *	handler when the demultiplexer does not know which device it its
566  *	multiplexed irq domain generated the interrupt. IRQ's handled
567  *	through here are not subjected to stats tracking, randomness, or
568  *	spurious interrupt detection.
569  *
570  *	Note: Like handle_simple_irq, the caller is expected to handle
571  *	the ack, clear, mask and unmask issues if necessary.
572  */
573 void handle_untracked_irq(struct irq_desc *desc)
574 {
575 	unsigned int flags = 0;
576 
577 	raw_spin_lock(&desc->lock);
578 
579 	if (!irq_may_run(desc))
580 		goto out_unlock;
581 
582 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
583 
584 	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
585 		desc->istate |= IRQS_PENDING;
586 		goto out_unlock;
587 	}
588 
589 	desc->istate &= ~IRQS_PENDING;
590 	irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
591 	raw_spin_unlock(&desc->lock);
592 
593 	__handle_irq_event_percpu(desc, &flags);
594 
595 	raw_spin_lock(&desc->lock);
596 	irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
597 
598 out_unlock:
599 	raw_spin_unlock(&desc->lock);
600 }
601 EXPORT_SYMBOL_GPL(handle_untracked_irq);
602 
603 /*
604  * Called unconditionally from handle_level_irq() and only for oneshot
605  * interrupts from handle_fasteoi_irq()
606  */
607 static void cond_unmask_irq(struct irq_desc *desc)
608 {
609 	/*
610 	 * We need to unmask in the following cases:
611 	 * - Standard level irq (IRQF_ONESHOT is not set)
612 	 * - Oneshot irq which did not wake the thread (caused by a
613 	 *   spurious interrupt or a primary handler handling it
614 	 *   completely).
615 	 */
616 	if (!irqd_irq_disabled(&desc->irq_data) &&
617 	    irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot)
618 		unmask_irq(desc);
619 }
620 
621 /**
622  *	handle_level_irq - Level type irq handler
623  *	@desc:	the interrupt description structure for this irq
624  *
625  *	Level type interrupts are active as long as the hardware line has
626  *	the active level. This may require to mask the interrupt and unmask
627  *	it after the associated handler has acknowledged the device, so the
628  *	interrupt line is back to inactive.
629  */
630 void handle_level_irq(struct irq_desc *desc)
631 {
632 	raw_spin_lock(&desc->lock);
633 	mask_ack_irq(desc);
634 
635 	if (!irq_may_run(desc))
636 		goto out_unlock;
637 
638 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
639 
640 	/*
641 	 * If its disabled or no action available
642 	 * keep it masked and get out of here
643 	 */
644 	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
645 		desc->istate |= IRQS_PENDING;
646 		goto out_unlock;
647 	}
648 
649 	kstat_incr_irqs_this_cpu(desc);
650 	handle_irq_event(desc);
651 
652 	cond_unmask_irq(desc);
653 
654 out_unlock:
655 	raw_spin_unlock(&desc->lock);
656 }
657 EXPORT_SYMBOL_GPL(handle_level_irq);
658 
659 #ifdef CONFIG_IRQ_PREFLOW_FASTEOI
660 static inline void preflow_handler(struct irq_desc *desc)
661 {
662 	if (desc->preflow_handler)
663 		desc->preflow_handler(&desc->irq_data);
664 }
665 #else
666 static inline void preflow_handler(struct irq_desc *desc) { }
667 #endif
668 
669 static void cond_unmask_eoi_irq(struct irq_desc *desc, struct irq_chip *chip)
670 {
671 	if (!(desc->istate & IRQS_ONESHOT)) {
672 		chip->irq_eoi(&desc->irq_data);
673 		return;
674 	}
675 	/*
676 	 * We need to unmask in the following cases:
677 	 * - Oneshot irq which did not wake the thread (caused by a
678 	 *   spurious interrupt or a primary handler handling it
679 	 *   completely).
680 	 */
681 	if (!irqd_irq_disabled(&desc->irq_data) &&
682 	    irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot) {
683 		chip->irq_eoi(&desc->irq_data);
684 		unmask_irq(desc);
685 	} else if (!(chip->flags & IRQCHIP_EOI_THREADED)) {
686 		chip->irq_eoi(&desc->irq_data);
687 	}
688 }
689 
690 /**
691  *	handle_fasteoi_irq - irq handler for transparent controllers
692  *	@desc:	the interrupt description structure for this irq
693  *
694  *	Only a single callback will be issued to the chip: an ->eoi()
695  *	call when the interrupt has been serviced. This enables support
696  *	for modern forms of interrupt handlers, which handle the flow
697  *	details in hardware, transparently.
698  */
699 void handle_fasteoi_irq(struct irq_desc *desc)
700 {
701 	struct irq_chip *chip = desc->irq_data.chip;
702 
703 	raw_spin_lock(&desc->lock);
704 
705 	if (!irq_may_run(desc))
706 		goto out;
707 
708 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
709 
710 	/*
711 	 * If its disabled or no action available
712 	 * then mask it and get out of here:
713 	 */
714 	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
715 		desc->istate |= IRQS_PENDING;
716 		mask_irq(desc);
717 		goto out;
718 	}
719 
720 	kstat_incr_irqs_this_cpu(desc);
721 	if (desc->istate & IRQS_ONESHOT)
722 		mask_irq(desc);
723 
724 	preflow_handler(desc);
725 	handle_irq_event(desc);
726 
727 	cond_unmask_eoi_irq(desc, chip);
728 
729 	raw_spin_unlock(&desc->lock);
730 	return;
731 out:
732 	if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED))
733 		chip->irq_eoi(&desc->irq_data);
734 	raw_spin_unlock(&desc->lock);
735 }
736 EXPORT_SYMBOL_GPL(handle_fasteoi_irq);
737 
738 /**
739  *	handle_fasteoi_nmi - irq handler for NMI interrupt lines
740  *	@desc:	the interrupt description structure for this irq
741  *
742  *	A simple NMI-safe handler, considering the restrictions
743  *	from request_nmi.
744  *
745  *	Only a single callback will be issued to the chip: an ->eoi()
746  *	call when the interrupt has been serviced. This enables support
747  *	for modern forms of interrupt handlers, which handle the flow
748  *	details in hardware, transparently.
749  */
750 void handle_fasteoi_nmi(struct irq_desc *desc)
751 {
752 	struct irq_chip *chip = irq_desc_get_chip(desc);
753 	struct irqaction *action = desc->action;
754 	unsigned int irq = irq_desc_get_irq(desc);
755 	irqreturn_t res;
756 
757 	__kstat_incr_irqs_this_cpu(desc);
758 
759 	trace_irq_handler_entry(irq, action);
760 	/*
761 	 * NMIs cannot be shared, there is only one action.
762 	 */
763 	res = action->handler(irq, action->dev_id);
764 	trace_irq_handler_exit(irq, action, res);
765 
766 	if (chip->irq_eoi)
767 		chip->irq_eoi(&desc->irq_data);
768 }
769 EXPORT_SYMBOL_GPL(handle_fasteoi_nmi);
770 
771 /**
772  *	handle_edge_irq - edge type IRQ handler
773  *	@desc:	the interrupt description structure for this irq
774  *
775  *	Interrupt occures on the falling and/or rising edge of a hardware
776  *	signal. The occurrence is latched into the irq controller hardware
777  *	and must be acked in order to be reenabled. After the ack another
778  *	interrupt can happen on the same source even before the first one
779  *	is handled by the associated event handler. If this happens it
780  *	might be necessary to disable (mask) the interrupt depending on the
781  *	controller hardware. This requires to reenable the interrupt inside
782  *	of the loop which handles the interrupts which have arrived while
783  *	the handler was running. If all pending interrupts are handled, the
784  *	loop is left.
785  */
786 void handle_edge_irq(struct irq_desc *desc)
787 {
788 	raw_spin_lock(&desc->lock);
789 
790 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
791 
792 	if (!irq_may_run(desc)) {
793 		desc->istate |= IRQS_PENDING;
794 		mask_ack_irq(desc);
795 		goto out_unlock;
796 	}
797 
798 	/*
799 	 * If its disabled or no action available then mask it and get
800 	 * out of here.
801 	 */
802 	if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
803 		desc->istate |= IRQS_PENDING;
804 		mask_ack_irq(desc);
805 		goto out_unlock;
806 	}
807 
808 	kstat_incr_irqs_this_cpu(desc);
809 
810 	/* Start handling the irq */
811 	desc->irq_data.chip->irq_ack(&desc->irq_data);
812 
813 	do {
814 		if (unlikely(!desc->action)) {
815 			mask_irq(desc);
816 			goto out_unlock;
817 		}
818 
819 		/*
820 		 * When another irq arrived while we were handling
821 		 * one, we could have masked the irq.
822 		 * Renable it, if it was not disabled in meantime.
823 		 */
824 		if (unlikely(desc->istate & IRQS_PENDING)) {
825 			if (!irqd_irq_disabled(&desc->irq_data) &&
826 			    irqd_irq_masked(&desc->irq_data))
827 				unmask_irq(desc);
828 		}
829 
830 		handle_irq_event(desc);
831 
832 	} while ((desc->istate & IRQS_PENDING) &&
833 		 !irqd_irq_disabled(&desc->irq_data));
834 
835 out_unlock:
836 	raw_spin_unlock(&desc->lock);
837 }
838 EXPORT_SYMBOL(handle_edge_irq);
839 
840 #ifdef CONFIG_IRQ_EDGE_EOI_HANDLER
841 /**
842  *	handle_edge_eoi_irq - edge eoi type IRQ handler
843  *	@desc:	the interrupt description structure for this irq
844  *
845  * Similar as the above handle_edge_irq, but using eoi and w/o the
846  * mask/unmask logic.
847  */
848 void handle_edge_eoi_irq(struct irq_desc *desc)
849 {
850 	struct irq_chip *chip = irq_desc_get_chip(desc);
851 
852 	raw_spin_lock(&desc->lock);
853 
854 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
855 
856 	if (!irq_may_run(desc)) {
857 		desc->istate |= IRQS_PENDING;
858 		goto out_eoi;
859 	}
860 
861 	/*
862 	 * If its disabled or no action available then mask it and get
863 	 * out of here.
864 	 */
865 	if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
866 		desc->istate |= IRQS_PENDING;
867 		goto out_eoi;
868 	}
869 
870 	kstat_incr_irqs_this_cpu(desc);
871 
872 	do {
873 		if (unlikely(!desc->action))
874 			goto out_eoi;
875 
876 		handle_irq_event(desc);
877 
878 	} while ((desc->istate & IRQS_PENDING) &&
879 		 !irqd_irq_disabled(&desc->irq_data));
880 
881 out_eoi:
882 	chip->irq_eoi(&desc->irq_data);
883 	raw_spin_unlock(&desc->lock);
884 }
885 #endif
886 
887 /**
888  *	handle_percpu_irq - Per CPU local irq handler
889  *	@desc:	the interrupt description structure for this irq
890  *
891  *	Per CPU interrupts on SMP machines without locking requirements
892  */
893 void handle_percpu_irq(struct irq_desc *desc)
894 {
895 	struct irq_chip *chip = irq_desc_get_chip(desc);
896 
897 	/*
898 	 * PER CPU interrupts are not serialized. Do not touch
899 	 * desc->tot_count.
900 	 */
901 	__kstat_incr_irqs_this_cpu(desc);
902 
903 	if (chip->irq_ack)
904 		chip->irq_ack(&desc->irq_data);
905 
906 	handle_irq_event_percpu(desc);
907 
908 	if (chip->irq_eoi)
909 		chip->irq_eoi(&desc->irq_data);
910 }
911 
912 /**
913  * handle_percpu_devid_irq - Per CPU local irq handler with per cpu dev ids
914  * @desc:	the interrupt description structure for this irq
915  *
916  * Per CPU interrupts on SMP machines without locking requirements. Same as
917  * handle_percpu_irq() above but with the following extras:
918  *
919  * action->percpu_dev_id is a pointer to percpu variables which
920  * contain the real device id for the cpu on which this handler is
921  * called
922  */
923 void handle_percpu_devid_irq(struct irq_desc *desc)
924 {
925 	struct irq_chip *chip = irq_desc_get_chip(desc);
926 	struct irqaction *action = desc->action;
927 	unsigned int irq = irq_desc_get_irq(desc);
928 	irqreturn_t res;
929 
930 	/*
931 	 * PER CPU interrupts are not serialized. Do not touch
932 	 * desc->tot_count.
933 	 */
934 	__kstat_incr_irqs_this_cpu(desc);
935 
936 	if (chip->irq_ack)
937 		chip->irq_ack(&desc->irq_data);
938 
939 	if (likely(action)) {
940 		trace_irq_handler_entry(irq, action);
941 		res = action->handler(irq, raw_cpu_ptr(action->percpu_dev_id));
942 		trace_irq_handler_exit(irq, action, res);
943 	} else {
944 		unsigned int cpu = smp_processor_id();
945 		bool enabled = cpumask_test_cpu(cpu, desc->percpu_enabled);
946 
947 		if (enabled)
948 			irq_percpu_disable(desc, cpu);
949 
950 		pr_err_once("Spurious%s percpu IRQ%u on CPU%u\n",
951 			    enabled ? " and unmasked" : "", irq, cpu);
952 	}
953 
954 	if (chip->irq_eoi)
955 		chip->irq_eoi(&desc->irq_data);
956 }
957 
958 /**
959  * handle_percpu_devid_fasteoi_nmi - Per CPU local NMI handler with per cpu
960  *				     dev ids
961  * @desc:	the interrupt description structure for this irq
962  *
963  * Similar to handle_fasteoi_nmi, but handling the dev_id cookie
964  * as a percpu pointer.
965  */
966 void handle_percpu_devid_fasteoi_nmi(struct irq_desc *desc)
967 {
968 	struct irq_chip *chip = irq_desc_get_chip(desc);
969 	struct irqaction *action = desc->action;
970 	unsigned int irq = irq_desc_get_irq(desc);
971 	irqreturn_t res;
972 
973 	__kstat_incr_irqs_this_cpu(desc);
974 
975 	trace_irq_handler_entry(irq, action);
976 	res = action->handler(irq, raw_cpu_ptr(action->percpu_dev_id));
977 	trace_irq_handler_exit(irq, action, res);
978 
979 	if (chip->irq_eoi)
980 		chip->irq_eoi(&desc->irq_data);
981 }
982 
983 static void
984 __irq_do_set_handler(struct irq_desc *desc, irq_flow_handler_t handle,
985 		     int is_chained, const char *name)
986 {
987 	if (!handle) {
988 		handle = handle_bad_irq;
989 	} else {
990 		struct irq_data *irq_data = &desc->irq_data;
991 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
992 		/*
993 		 * With hierarchical domains we might run into a
994 		 * situation where the outermost chip is not yet set
995 		 * up, but the inner chips are there.  Instead of
996 		 * bailing we install the handler, but obviously we
997 		 * cannot enable/startup the interrupt at this point.
998 		 */
999 		while (irq_data) {
1000 			if (irq_data->chip != &no_irq_chip)
1001 				break;
1002 			/*
1003 			 * Bail out if the outer chip is not set up
1004 			 * and the interrupt supposed to be started
1005 			 * right away.
1006 			 */
1007 			if (WARN_ON(is_chained))
1008 				return;
1009 			/* Try the parent */
1010 			irq_data = irq_data->parent_data;
1011 		}
1012 #endif
1013 		if (WARN_ON(!irq_data || irq_data->chip == &no_irq_chip))
1014 			return;
1015 	}
1016 
1017 	/* Uninstall? */
1018 	if (handle == handle_bad_irq) {
1019 		if (desc->irq_data.chip != &no_irq_chip)
1020 			mask_ack_irq(desc);
1021 		irq_state_set_disabled(desc);
1022 		if (is_chained)
1023 			desc->action = NULL;
1024 		desc->depth = 1;
1025 	}
1026 	desc->handle_irq = handle;
1027 	desc->name = name;
1028 
1029 	if (handle != handle_bad_irq && is_chained) {
1030 		unsigned int type = irqd_get_trigger_type(&desc->irq_data);
1031 
1032 		/*
1033 		 * We're about to start this interrupt immediately,
1034 		 * hence the need to set the trigger configuration.
1035 		 * But the .set_type callback may have overridden the
1036 		 * flow handler, ignoring that we're dealing with a
1037 		 * chained interrupt. Reset it immediately because we
1038 		 * do know better.
1039 		 */
1040 		if (type != IRQ_TYPE_NONE) {
1041 			__irq_set_trigger(desc, type);
1042 			desc->handle_irq = handle;
1043 		}
1044 
1045 		irq_settings_set_noprobe(desc);
1046 		irq_settings_set_norequest(desc);
1047 		irq_settings_set_nothread(desc);
1048 		desc->action = &chained_action;
1049 		irq_activate_and_startup(desc, IRQ_RESEND);
1050 	}
1051 }
1052 
1053 void
1054 __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
1055 		  const char *name)
1056 {
1057 	unsigned long flags;
1058 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
1059 
1060 	if (!desc)
1061 		return;
1062 
1063 	__irq_do_set_handler(desc, handle, is_chained, name);
1064 	irq_put_desc_busunlock(desc, flags);
1065 }
1066 EXPORT_SYMBOL_GPL(__irq_set_handler);
1067 
1068 void
1069 irq_set_chained_handler_and_data(unsigned int irq, irq_flow_handler_t handle,
1070 				 void *data)
1071 {
1072 	unsigned long flags;
1073 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
1074 
1075 	if (!desc)
1076 		return;
1077 
1078 	desc->irq_common_data.handler_data = data;
1079 	__irq_do_set_handler(desc, handle, 1, NULL);
1080 
1081 	irq_put_desc_busunlock(desc, flags);
1082 }
1083 EXPORT_SYMBOL_GPL(irq_set_chained_handler_and_data);
1084 
1085 void
1086 irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
1087 			      irq_flow_handler_t handle, const char *name)
1088 {
1089 	irq_set_chip(irq, chip);
1090 	__irq_set_handler(irq, handle, 0, name);
1091 }
1092 EXPORT_SYMBOL_GPL(irq_set_chip_and_handler_name);
1093 
1094 void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
1095 {
1096 	unsigned long flags, trigger, tmp;
1097 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
1098 
1099 	if (!desc)
1100 		return;
1101 
1102 	/*
1103 	 * Warn when a driver sets the no autoenable flag on an already
1104 	 * active interrupt.
1105 	 */
1106 	WARN_ON_ONCE(!desc->depth && (set & _IRQ_NOAUTOEN));
1107 
1108 	irq_settings_clr_and_set(desc, clr, set);
1109 
1110 	trigger = irqd_get_trigger_type(&desc->irq_data);
1111 
1112 	irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU |
1113 		   IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT);
1114 	if (irq_settings_has_no_balance_set(desc))
1115 		irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
1116 	if (irq_settings_is_per_cpu(desc))
1117 		irqd_set(&desc->irq_data, IRQD_PER_CPU);
1118 	if (irq_settings_can_move_pcntxt(desc))
1119 		irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT);
1120 	if (irq_settings_is_level(desc))
1121 		irqd_set(&desc->irq_data, IRQD_LEVEL);
1122 
1123 	tmp = irq_settings_get_trigger_mask(desc);
1124 	if (tmp != IRQ_TYPE_NONE)
1125 		trigger = tmp;
1126 
1127 	irqd_set(&desc->irq_data, trigger);
1128 
1129 	irq_put_desc_unlock(desc, flags);
1130 }
1131 EXPORT_SYMBOL_GPL(irq_modify_status);
1132 
1133 /**
1134  *	irq_cpu_online - Invoke all irq_cpu_online functions.
1135  *
1136  *	Iterate through all irqs and invoke the chip.irq_cpu_online()
1137  *	for each.
1138  */
1139 void irq_cpu_online(void)
1140 {
1141 	struct irq_desc *desc;
1142 	struct irq_chip *chip;
1143 	unsigned long flags;
1144 	unsigned int irq;
1145 
1146 	for_each_active_irq(irq) {
1147 		desc = irq_to_desc(irq);
1148 		if (!desc)
1149 			continue;
1150 
1151 		raw_spin_lock_irqsave(&desc->lock, flags);
1152 
1153 		chip = irq_data_get_irq_chip(&desc->irq_data);
1154 		if (chip && chip->irq_cpu_online &&
1155 		    (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
1156 		     !irqd_irq_disabled(&desc->irq_data)))
1157 			chip->irq_cpu_online(&desc->irq_data);
1158 
1159 		raw_spin_unlock_irqrestore(&desc->lock, flags);
1160 	}
1161 }
1162 
1163 /**
1164  *	irq_cpu_offline - Invoke all irq_cpu_offline functions.
1165  *
1166  *	Iterate through all irqs and invoke the chip.irq_cpu_offline()
1167  *	for each.
1168  */
1169 void irq_cpu_offline(void)
1170 {
1171 	struct irq_desc *desc;
1172 	struct irq_chip *chip;
1173 	unsigned long flags;
1174 	unsigned int irq;
1175 
1176 	for_each_active_irq(irq) {
1177 		desc = irq_to_desc(irq);
1178 		if (!desc)
1179 			continue;
1180 
1181 		raw_spin_lock_irqsave(&desc->lock, flags);
1182 
1183 		chip = irq_data_get_irq_chip(&desc->irq_data);
1184 		if (chip && chip->irq_cpu_offline &&
1185 		    (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
1186 		     !irqd_irq_disabled(&desc->irq_data)))
1187 			chip->irq_cpu_offline(&desc->irq_data);
1188 
1189 		raw_spin_unlock_irqrestore(&desc->lock, flags);
1190 	}
1191 }
1192 
1193 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
1194 
1195 #ifdef CONFIG_IRQ_FASTEOI_HIERARCHY_HANDLERS
1196 /**
1197  *	handle_fasteoi_ack_irq - irq handler for edge hierarchy
1198  *	stacked on transparent controllers
1199  *
1200  *	@desc:	the interrupt description structure for this irq
1201  *
1202  *	Like handle_fasteoi_irq(), but for use with hierarchy where
1203  *	the irq_chip also needs to have its ->irq_ack() function
1204  *	called.
1205  */
1206 void handle_fasteoi_ack_irq(struct irq_desc *desc)
1207 {
1208 	struct irq_chip *chip = desc->irq_data.chip;
1209 
1210 	raw_spin_lock(&desc->lock);
1211 
1212 	if (!irq_may_run(desc))
1213 		goto out;
1214 
1215 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
1216 
1217 	/*
1218 	 * If its disabled or no action available
1219 	 * then mask it and get out of here:
1220 	 */
1221 	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
1222 		desc->istate |= IRQS_PENDING;
1223 		mask_irq(desc);
1224 		goto out;
1225 	}
1226 
1227 	kstat_incr_irqs_this_cpu(desc);
1228 	if (desc->istate & IRQS_ONESHOT)
1229 		mask_irq(desc);
1230 
1231 	/* Start handling the irq */
1232 	desc->irq_data.chip->irq_ack(&desc->irq_data);
1233 
1234 	preflow_handler(desc);
1235 	handle_irq_event(desc);
1236 
1237 	cond_unmask_eoi_irq(desc, chip);
1238 
1239 	raw_spin_unlock(&desc->lock);
1240 	return;
1241 out:
1242 	if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED))
1243 		chip->irq_eoi(&desc->irq_data);
1244 	raw_spin_unlock(&desc->lock);
1245 }
1246 EXPORT_SYMBOL_GPL(handle_fasteoi_ack_irq);
1247 
1248 /**
1249  *	handle_fasteoi_mask_irq - irq handler for level hierarchy
1250  *	stacked on transparent controllers
1251  *
1252  *	@desc:	the interrupt description structure for this irq
1253  *
1254  *	Like handle_fasteoi_irq(), but for use with hierarchy where
1255  *	the irq_chip also needs to have its ->irq_mask_ack() function
1256  *	called.
1257  */
1258 void handle_fasteoi_mask_irq(struct irq_desc *desc)
1259 {
1260 	struct irq_chip *chip = desc->irq_data.chip;
1261 
1262 	raw_spin_lock(&desc->lock);
1263 	mask_ack_irq(desc);
1264 
1265 	if (!irq_may_run(desc))
1266 		goto out;
1267 
1268 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
1269 
1270 	/*
1271 	 * If its disabled or no action available
1272 	 * then mask it and get out of here:
1273 	 */
1274 	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
1275 		desc->istate |= IRQS_PENDING;
1276 		mask_irq(desc);
1277 		goto out;
1278 	}
1279 
1280 	kstat_incr_irqs_this_cpu(desc);
1281 	if (desc->istate & IRQS_ONESHOT)
1282 		mask_irq(desc);
1283 
1284 	preflow_handler(desc);
1285 	handle_irq_event(desc);
1286 
1287 	cond_unmask_eoi_irq(desc, chip);
1288 
1289 	raw_spin_unlock(&desc->lock);
1290 	return;
1291 out:
1292 	if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED))
1293 		chip->irq_eoi(&desc->irq_data);
1294 	raw_spin_unlock(&desc->lock);
1295 }
1296 EXPORT_SYMBOL_GPL(handle_fasteoi_mask_irq);
1297 
1298 #endif /* CONFIG_IRQ_FASTEOI_HIERARCHY_HANDLERS */
1299 
1300 /**
1301  * irq_chip_set_parent_state - set the state of a parent interrupt.
1302  *
1303  * @data: Pointer to interrupt specific data
1304  * @which: State to be restored (one of IRQCHIP_STATE_*)
1305  * @val: Value corresponding to @which
1306  *
1307  * Conditional success, if the underlying irqchip does not implement it.
1308  */
1309 int irq_chip_set_parent_state(struct irq_data *data,
1310 			      enum irqchip_irq_state which,
1311 			      bool val)
1312 {
1313 	data = data->parent_data;
1314 
1315 	if (!data || !data->chip->irq_set_irqchip_state)
1316 		return 0;
1317 
1318 	return data->chip->irq_set_irqchip_state(data, which, val);
1319 }
1320 EXPORT_SYMBOL_GPL(irq_chip_set_parent_state);
1321 
1322 /**
1323  * irq_chip_get_parent_state - get the state of a parent interrupt.
1324  *
1325  * @data: Pointer to interrupt specific data
1326  * @which: one of IRQCHIP_STATE_* the caller wants to know
1327  * @state: a pointer to a boolean where the state is to be stored
1328  *
1329  * Conditional success, if the underlying irqchip does not implement it.
1330  */
1331 int irq_chip_get_parent_state(struct irq_data *data,
1332 			      enum irqchip_irq_state which,
1333 			      bool *state)
1334 {
1335 	data = data->parent_data;
1336 
1337 	if (!data || !data->chip->irq_get_irqchip_state)
1338 		return 0;
1339 
1340 	return data->chip->irq_get_irqchip_state(data, which, state);
1341 }
1342 EXPORT_SYMBOL_GPL(irq_chip_get_parent_state);
1343 
1344 /**
1345  * irq_chip_enable_parent - Enable the parent interrupt (defaults to unmask if
1346  * NULL)
1347  * @data:	Pointer to interrupt specific data
1348  */
1349 void irq_chip_enable_parent(struct irq_data *data)
1350 {
1351 	data = data->parent_data;
1352 	if (data->chip->irq_enable)
1353 		data->chip->irq_enable(data);
1354 	else
1355 		data->chip->irq_unmask(data);
1356 }
1357 EXPORT_SYMBOL_GPL(irq_chip_enable_parent);
1358 
1359 /**
1360  * irq_chip_disable_parent - Disable the parent interrupt (defaults to mask if
1361  * NULL)
1362  * @data:	Pointer to interrupt specific data
1363  */
1364 void irq_chip_disable_parent(struct irq_data *data)
1365 {
1366 	data = data->parent_data;
1367 	if (data->chip->irq_disable)
1368 		data->chip->irq_disable(data);
1369 	else
1370 		data->chip->irq_mask(data);
1371 }
1372 EXPORT_SYMBOL_GPL(irq_chip_disable_parent);
1373 
1374 /**
1375  * irq_chip_ack_parent - Acknowledge the parent interrupt
1376  * @data:	Pointer to interrupt specific data
1377  */
1378 void irq_chip_ack_parent(struct irq_data *data)
1379 {
1380 	data = data->parent_data;
1381 	data->chip->irq_ack(data);
1382 }
1383 EXPORT_SYMBOL_GPL(irq_chip_ack_parent);
1384 
1385 /**
1386  * irq_chip_mask_parent - Mask the parent interrupt
1387  * @data:	Pointer to interrupt specific data
1388  */
1389 void irq_chip_mask_parent(struct irq_data *data)
1390 {
1391 	data = data->parent_data;
1392 	data->chip->irq_mask(data);
1393 }
1394 EXPORT_SYMBOL_GPL(irq_chip_mask_parent);
1395 
1396 /**
1397  * irq_chip_mask_ack_parent - Mask and acknowledge the parent interrupt
1398  * @data:	Pointer to interrupt specific data
1399  */
1400 void irq_chip_mask_ack_parent(struct irq_data *data)
1401 {
1402 	data = data->parent_data;
1403 	data->chip->irq_mask_ack(data);
1404 }
1405 EXPORT_SYMBOL_GPL(irq_chip_mask_ack_parent);
1406 
1407 /**
1408  * irq_chip_unmask_parent - Unmask the parent interrupt
1409  * @data:	Pointer to interrupt specific data
1410  */
1411 void irq_chip_unmask_parent(struct irq_data *data)
1412 {
1413 	data = data->parent_data;
1414 	data->chip->irq_unmask(data);
1415 }
1416 EXPORT_SYMBOL_GPL(irq_chip_unmask_parent);
1417 
1418 /**
1419  * irq_chip_eoi_parent - Invoke EOI on the parent interrupt
1420  * @data:	Pointer to interrupt specific data
1421  */
1422 void irq_chip_eoi_parent(struct irq_data *data)
1423 {
1424 	data = data->parent_data;
1425 	data->chip->irq_eoi(data);
1426 }
1427 EXPORT_SYMBOL_GPL(irq_chip_eoi_parent);
1428 
1429 /**
1430  * irq_chip_set_affinity_parent - Set affinity on the parent interrupt
1431  * @data:	Pointer to interrupt specific data
1432  * @dest:	The affinity mask to set
1433  * @force:	Flag to enforce setting (disable online checks)
1434  *
1435  * Conditinal, as the underlying parent chip might not implement it.
1436  */
1437 int irq_chip_set_affinity_parent(struct irq_data *data,
1438 				 const struct cpumask *dest, bool force)
1439 {
1440 	data = data->parent_data;
1441 	if (data->chip->irq_set_affinity)
1442 		return data->chip->irq_set_affinity(data, dest, force);
1443 
1444 	return -ENOSYS;
1445 }
1446 EXPORT_SYMBOL_GPL(irq_chip_set_affinity_parent);
1447 
1448 /**
1449  * irq_chip_set_type_parent - Set IRQ type on the parent interrupt
1450  * @data:	Pointer to interrupt specific data
1451  * @type:	IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
1452  *
1453  * Conditional, as the underlying parent chip might not implement it.
1454  */
1455 int irq_chip_set_type_parent(struct irq_data *data, unsigned int type)
1456 {
1457 	data = data->parent_data;
1458 
1459 	if (data->chip->irq_set_type)
1460 		return data->chip->irq_set_type(data, type);
1461 
1462 	return -ENOSYS;
1463 }
1464 EXPORT_SYMBOL_GPL(irq_chip_set_type_parent);
1465 
1466 /**
1467  * irq_chip_retrigger_hierarchy - Retrigger an interrupt in hardware
1468  * @data:	Pointer to interrupt specific data
1469  *
1470  * Iterate through the domain hierarchy of the interrupt and check
1471  * whether a hw retrigger function exists. If yes, invoke it.
1472  */
1473 int irq_chip_retrigger_hierarchy(struct irq_data *data)
1474 {
1475 	for (data = data->parent_data; data; data = data->parent_data)
1476 		if (data->chip && data->chip->irq_retrigger)
1477 			return data->chip->irq_retrigger(data);
1478 
1479 	return 0;
1480 }
1481 
1482 /**
1483  * irq_chip_set_vcpu_affinity_parent - Set vcpu affinity on the parent interrupt
1484  * @data:	Pointer to interrupt specific data
1485  * @vcpu_info:	The vcpu affinity information
1486  */
1487 int irq_chip_set_vcpu_affinity_parent(struct irq_data *data, void *vcpu_info)
1488 {
1489 	data = data->parent_data;
1490 	if (data->chip->irq_set_vcpu_affinity)
1491 		return data->chip->irq_set_vcpu_affinity(data, vcpu_info);
1492 
1493 	return -ENOSYS;
1494 }
1495 
1496 /**
1497  * irq_chip_set_wake_parent - Set/reset wake-up on the parent interrupt
1498  * @data:	Pointer to interrupt specific data
1499  * @on:		Whether to set or reset the wake-up capability of this irq
1500  *
1501  * Conditional, as the underlying parent chip might not implement it.
1502  */
1503 int irq_chip_set_wake_parent(struct irq_data *data, unsigned int on)
1504 {
1505 	data = data->parent_data;
1506 
1507 	if (data->chip->flags & IRQCHIP_SKIP_SET_WAKE)
1508 		return 0;
1509 
1510 	if (data->chip->irq_set_wake)
1511 		return data->chip->irq_set_wake(data, on);
1512 
1513 	return -ENOSYS;
1514 }
1515 EXPORT_SYMBOL_GPL(irq_chip_set_wake_parent);
1516 
1517 /**
1518  * irq_chip_request_resources_parent - Request resources on the parent interrupt
1519  * @data:	Pointer to interrupt specific data
1520  */
1521 int irq_chip_request_resources_parent(struct irq_data *data)
1522 {
1523 	data = data->parent_data;
1524 
1525 	if (data->chip->irq_request_resources)
1526 		return data->chip->irq_request_resources(data);
1527 
1528 	return -ENOSYS;
1529 }
1530 EXPORT_SYMBOL_GPL(irq_chip_request_resources_parent);
1531 
1532 /**
1533  * irq_chip_release_resources_parent - Release resources on the parent interrupt
1534  * @data:	Pointer to interrupt specific data
1535  */
1536 void irq_chip_release_resources_parent(struct irq_data *data)
1537 {
1538 	data = data->parent_data;
1539 	if (data->chip->irq_release_resources)
1540 		data->chip->irq_release_resources(data);
1541 }
1542 EXPORT_SYMBOL_GPL(irq_chip_release_resources_parent);
1543 #endif
1544 
1545 /**
1546  * irq_chip_compose_msi_msg - Componse msi message for a irq chip
1547  * @data:	Pointer to interrupt specific data
1548  * @msg:	Pointer to the MSI message
1549  *
1550  * For hierarchical domains we find the first chip in the hierarchy
1551  * which implements the irq_compose_msi_msg callback. For non
1552  * hierarchical we use the top level chip.
1553  */
1554 int irq_chip_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
1555 {
1556 	struct irq_data *pos = NULL;
1557 
1558 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
1559 	for (; data; data = data->parent_data)
1560 #endif
1561 		if (data->chip && data->chip->irq_compose_msi_msg)
1562 			pos = data;
1563 	if (!pos)
1564 		return -ENOSYS;
1565 
1566 	pos->chip->irq_compose_msi_msg(pos, msg);
1567 
1568 	return 0;
1569 }
1570 
1571 /**
1572  * irq_chip_pm_get - Enable power for an IRQ chip
1573  * @data:	Pointer to interrupt specific data
1574  *
1575  * Enable the power to the IRQ chip referenced by the interrupt data
1576  * structure.
1577  */
1578 int irq_chip_pm_get(struct irq_data *data)
1579 {
1580 	int retval;
1581 
1582 	if (IS_ENABLED(CONFIG_PM) && data->chip->parent_device) {
1583 		retval = pm_runtime_get_sync(data->chip->parent_device);
1584 		if (retval < 0) {
1585 			pm_runtime_put_noidle(data->chip->parent_device);
1586 			return retval;
1587 		}
1588 	}
1589 
1590 	return 0;
1591 }
1592 
1593 /**
1594  * irq_chip_pm_put - Disable power for an IRQ chip
1595  * @data:	Pointer to interrupt specific data
1596  *
1597  * Disable the power to the IRQ chip referenced by the interrupt data
1598  * structure, belongs. Note that power will only be disabled, once this
1599  * function has been called for all IRQs that have called irq_chip_pm_get().
1600  */
1601 int irq_chip_pm_put(struct irq_data *data)
1602 {
1603 	int retval = 0;
1604 
1605 	if (IS_ENABLED(CONFIG_PM) && data->chip->parent_device)
1606 		retval = pm_runtime_put(data->chip->parent_device);
1607 
1608 	return (retval < 0) ? retval : 0;
1609 }
1610