xref: /openbmc/linux/kernel/irq/chip.c (revision a2cce7a9)
1 /*
2  * linux/kernel/irq/chip.c
3  *
4  * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
5  * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
6  *
7  * This file contains the core interrupt handling code, for irq-chip
8  * based architectures.
9  *
10  * Detailed information is available in Documentation/DocBook/genericirq
11  */
12 
13 #include <linux/irq.h>
14 #include <linux/msi.h>
15 #include <linux/module.h>
16 #include <linux/interrupt.h>
17 #include <linux/kernel_stat.h>
18 #include <linux/irqdomain.h>
19 
20 #include <trace/events/irq.h>
21 
22 #include "internals.h"
23 
24 /**
25  *	irq_set_chip - set the irq chip for an irq
26  *	@irq:	irq number
27  *	@chip:	pointer to irq chip description structure
28  */
29 int irq_set_chip(unsigned int irq, struct irq_chip *chip)
30 {
31 	unsigned long flags;
32 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
33 
34 	if (!desc)
35 		return -EINVAL;
36 
37 	if (!chip)
38 		chip = &no_irq_chip;
39 
40 	desc->irq_data.chip = chip;
41 	irq_put_desc_unlock(desc, flags);
42 	/*
43 	 * For !CONFIG_SPARSE_IRQ make the irq show up in
44 	 * allocated_irqs.
45 	 */
46 	irq_mark_irq(irq);
47 	return 0;
48 }
49 EXPORT_SYMBOL(irq_set_chip);
50 
51 /**
52  *	irq_set_type - set the irq trigger type for an irq
53  *	@irq:	irq number
54  *	@type:	IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
55  */
56 int irq_set_irq_type(unsigned int irq, unsigned int type)
57 {
58 	unsigned long flags;
59 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
60 	int ret = 0;
61 
62 	if (!desc)
63 		return -EINVAL;
64 
65 	type &= IRQ_TYPE_SENSE_MASK;
66 	ret = __irq_set_trigger(desc, type);
67 	irq_put_desc_busunlock(desc, flags);
68 	return ret;
69 }
70 EXPORT_SYMBOL(irq_set_irq_type);
71 
72 /**
73  *	irq_set_handler_data - set irq handler data for an irq
74  *	@irq:	Interrupt number
75  *	@data:	Pointer to interrupt specific data
76  *
77  *	Set the hardware irq controller data for an irq
78  */
79 int irq_set_handler_data(unsigned int irq, void *data)
80 {
81 	unsigned long flags;
82 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
83 
84 	if (!desc)
85 		return -EINVAL;
86 	desc->irq_common_data.handler_data = data;
87 	irq_put_desc_unlock(desc, flags);
88 	return 0;
89 }
90 EXPORT_SYMBOL(irq_set_handler_data);
91 
92 /**
93  *	irq_set_msi_desc_off - set MSI descriptor data for an irq at offset
94  *	@irq_base:	Interrupt number base
95  *	@irq_offset:	Interrupt number offset
96  *	@entry:		Pointer to MSI descriptor data
97  *
98  *	Set the MSI descriptor entry for an irq at offset
99  */
100 int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset,
101 			 struct msi_desc *entry)
102 {
103 	unsigned long flags;
104 	struct irq_desc *desc = irq_get_desc_lock(irq_base + irq_offset, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
105 
106 	if (!desc)
107 		return -EINVAL;
108 	desc->irq_common_data.msi_desc = entry;
109 	if (entry && !irq_offset)
110 		entry->irq = irq_base;
111 	irq_put_desc_unlock(desc, flags);
112 	return 0;
113 }
114 
115 /**
116  *	irq_set_msi_desc - set MSI descriptor data for an irq
117  *	@irq:	Interrupt number
118  *	@entry:	Pointer to MSI descriptor data
119  *
120  *	Set the MSI descriptor entry for an irq
121  */
122 int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry)
123 {
124 	return irq_set_msi_desc_off(irq, 0, entry);
125 }
126 
127 /**
128  *	irq_set_chip_data - set irq chip data for an irq
129  *	@irq:	Interrupt number
130  *	@data:	Pointer to chip specific data
131  *
132  *	Set the hardware irq chip data for an irq
133  */
134 int irq_set_chip_data(unsigned int irq, void *data)
135 {
136 	unsigned long flags;
137 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
138 
139 	if (!desc)
140 		return -EINVAL;
141 	desc->irq_data.chip_data = data;
142 	irq_put_desc_unlock(desc, flags);
143 	return 0;
144 }
145 EXPORT_SYMBOL(irq_set_chip_data);
146 
147 struct irq_data *irq_get_irq_data(unsigned int irq)
148 {
149 	struct irq_desc *desc = irq_to_desc(irq);
150 
151 	return desc ? &desc->irq_data : NULL;
152 }
153 EXPORT_SYMBOL_GPL(irq_get_irq_data);
154 
155 static void irq_state_clr_disabled(struct irq_desc *desc)
156 {
157 	irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED);
158 }
159 
160 static void irq_state_set_disabled(struct irq_desc *desc)
161 {
162 	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
163 }
164 
165 static void irq_state_clr_masked(struct irq_desc *desc)
166 {
167 	irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED);
168 }
169 
170 static void irq_state_set_masked(struct irq_desc *desc)
171 {
172 	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
173 }
174 
175 int irq_startup(struct irq_desc *desc, bool resend)
176 {
177 	int ret = 0;
178 
179 	irq_state_clr_disabled(desc);
180 	desc->depth = 0;
181 
182 	irq_domain_activate_irq(&desc->irq_data);
183 	if (desc->irq_data.chip->irq_startup) {
184 		ret = desc->irq_data.chip->irq_startup(&desc->irq_data);
185 		irq_state_clr_masked(desc);
186 	} else {
187 		irq_enable(desc);
188 	}
189 	if (resend)
190 		check_irq_resend(desc);
191 	return ret;
192 }
193 
194 void irq_shutdown(struct irq_desc *desc)
195 {
196 	irq_state_set_disabled(desc);
197 	desc->depth = 1;
198 	if (desc->irq_data.chip->irq_shutdown)
199 		desc->irq_data.chip->irq_shutdown(&desc->irq_data);
200 	else if (desc->irq_data.chip->irq_disable)
201 		desc->irq_data.chip->irq_disable(&desc->irq_data);
202 	else
203 		desc->irq_data.chip->irq_mask(&desc->irq_data);
204 	irq_domain_deactivate_irq(&desc->irq_data);
205 	irq_state_set_masked(desc);
206 }
207 
208 void irq_enable(struct irq_desc *desc)
209 {
210 	irq_state_clr_disabled(desc);
211 	if (desc->irq_data.chip->irq_enable)
212 		desc->irq_data.chip->irq_enable(&desc->irq_data);
213 	else
214 		desc->irq_data.chip->irq_unmask(&desc->irq_data);
215 	irq_state_clr_masked(desc);
216 }
217 
218 /**
219  * irq_disable - Mark interrupt disabled
220  * @desc:	irq descriptor which should be disabled
221  *
222  * If the chip does not implement the irq_disable callback, we
223  * use a lazy disable approach. That means we mark the interrupt
224  * disabled, but leave the hardware unmasked. That's an
225  * optimization because we avoid the hardware access for the
226  * common case where no interrupt happens after we marked it
227  * disabled. If an interrupt happens, then the interrupt flow
228  * handler masks the line at the hardware level and marks it
229  * pending.
230  */
231 void irq_disable(struct irq_desc *desc)
232 {
233 	irq_state_set_disabled(desc);
234 	if (desc->irq_data.chip->irq_disable) {
235 		desc->irq_data.chip->irq_disable(&desc->irq_data);
236 		irq_state_set_masked(desc);
237 	}
238 }
239 
240 void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu)
241 {
242 	if (desc->irq_data.chip->irq_enable)
243 		desc->irq_data.chip->irq_enable(&desc->irq_data);
244 	else
245 		desc->irq_data.chip->irq_unmask(&desc->irq_data);
246 	cpumask_set_cpu(cpu, desc->percpu_enabled);
247 }
248 
249 void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu)
250 {
251 	if (desc->irq_data.chip->irq_disable)
252 		desc->irq_data.chip->irq_disable(&desc->irq_data);
253 	else
254 		desc->irq_data.chip->irq_mask(&desc->irq_data);
255 	cpumask_clear_cpu(cpu, desc->percpu_enabled);
256 }
257 
258 static inline void mask_ack_irq(struct irq_desc *desc)
259 {
260 	if (desc->irq_data.chip->irq_mask_ack)
261 		desc->irq_data.chip->irq_mask_ack(&desc->irq_data);
262 	else {
263 		desc->irq_data.chip->irq_mask(&desc->irq_data);
264 		if (desc->irq_data.chip->irq_ack)
265 			desc->irq_data.chip->irq_ack(&desc->irq_data);
266 	}
267 	irq_state_set_masked(desc);
268 }
269 
270 void mask_irq(struct irq_desc *desc)
271 {
272 	if (desc->irq_data.chip->irq_mask) {
273 		desc->irq_data.chip->irq_mask(&desc->irq_data);
274 		irq_state_set_masked(desc);
275 	}
276 }
277 
278 void unmask_irq(struct irq_desc *desc)
279 {
280 	if (desc->irq_data.chip->irq_unmask) {
281 		desc->irq_data.chip->irq_unmask(&desc->irq_data);
282 		irq_state_clr_masked(desc);
283 	}
284 }
285 
286 void unmask_threaded_irq(struct irq_desc *desc)
287 {
288 	struct irq_chip *chip = desc->irq_data.chip;
289 
290 	if (chip->flags & IRQCHIP_EOI_THREADED)
291 		chip->irq_eoi(&desc->irq_data);
292 
293 	if (chip->irq_unmask) {
294 		chip->irq_unmask(&desc->irq_data);
295 		irq_state_clr_masked(desc);
296 	}
297 }
298 
299 /*
300  *	handle_nested_irq - Handle a nested irq from a irq thread
301  *	@irq:	the interrupt number
302  *
303  *	Handle interrupts which are nested into a threaded interrupt
304  *	handler. The handler function is called inside the calling
305  *	threads context.
306  */
307 void handle_nested_irq(unsigned int irq)
308 {
309 	struct irq_desc *desc = irq_to_desc(irq);
310 	struct irqaction *action;
311 	irqreturn_t action_ret;
312 
313 	might_sleep();
314 
315 	raw_spin_lock_irq(&desc->lock);
316 
317 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
318 	kstat_incr_irqs_this_cpu(desc);
319 
320 	action = desc->action;
321 	if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) {
322 		desc->istate |= IRQS_PENDING;
323 		goto out_unlock;
324 	}
325 
326 	irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
327 	raw_spin_unlock_irq(&desc->lock);
328 
329 	action_ret = action->thread_fn(action->irq, action->dev_id);
330 	if (!noirqdebug)
331 		note_interrupt(desc, action_ret);
332 
333 	raw_spin_lock_irq(&desc->lock);
334 	irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
335 
336 out_unlock:
337 	raw_spin_unlock_irq(&desc->lock);
338 }
339 EXPORT_SYMBOL_GPL(handle_nested_irq);
340 
341 static bool irq_check_poll(struct irq_desc *desc)
342 {
343 	if (!(desc->istate & IRQS_POLL_INPROGRESS))
344 		return false;
345 	return irq_wait_for_poll(desc);
346 }
347 
348 static bool irq_may_run(struct irq_desc *desc)
349 {
350 	unsigned int mask = IRQD_IRQ_INPROGRESS | IRQD_WAKEUP_ARMED;
351 
352 	/*
353 	 * If the interrupt is not in progress and is not an armed
354 	 * wakeup interrupt, proceed.
355 	 */
356 	if (!irqd_has_set(&desc->irq_data, mask))
357 		return true;
358 
359 	/*
360 	 * If the interrupt is an armed wakeup source, mark it pending
361 	 * and suspended, disable it and notify the pm core about the
362 	 * event.
363 	 */
364 	if (irq_pm_check_wakeup(desc))
365 		return false;
366 
367 	/*
368 	 * Handle a potential concurrent poll on a different core.
369 	 */
370 	return irq_check_poll(desc);
371 }
372 
373 /**
374  *	handle_simple_irq - Simple and software-decoded IRQs.
375  *	@desc:	the interrupt description structure for this irq
376  *
377  *	Simple interrupts are either sent from a demultiplexing interrupt
378  *	handler or come from hardware, where no interrupt hardware control
379  *	is necessary.
380  *
381  *	Note: The caller is expected to handle the ack, clear, mask and
382  *	unmask issues if necessary.
383  */
384 void handle_simple_irq(struct irq_desc *desc)
385 {
386 	raw_spin_lock(&desc->lock);
387 
388 	if (!irq_may_run(desc))
389 		goto out_unlock;
390 
391 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
392 	kstat_incr_irqs_this_cpu(desc);
393 
394 	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
395 		desc->istate |= IRQS_PENDING;
396 		goto out_unlock;
397 	}
398 
399 	handle_irq_event(desc);
400 
401 out_unlock:
402 	raw_spin_unlock(&desc->lock);
403 }
404 EXPORT_SYMBOL_GPL(handle_simple_irq);
405 
406 /*
407  * Called unconditionally from handle_level_irq() and only for oneshot
408  * interrupts from handle_fasteoi_irq()
409  */
410 static void cond_unmask_irq(struct irq_desc *desc)
411 {
412 	/*
413 	 * We need to unmask in the following cases:
414 	 * - Standard level irq (IRQF_ONESHOT is not set)
415 	 * - Oneshot irq which did not wake the thread (caused by a
416 	 *   spurious interrupt or a primary handler handling it
417 	 *   completely).
418 	 */
419 	if (!irqd_irq_disabled(&desc->irq_data) &&
420 	    irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot)
421 		unmask_irq(desc);
422 }
423 
424 /**
425  *	handle_level_irq - Level type irq handler
426  *	@desc:	the interrupt description structure for this irq
427  *
428  *	Level type interrupts are active as long as the hardware line has
429  *	the active level. This may require to mask the interrupt and unmask
430  *	it after the associated handler has acknowledged the device, so the
431  *	interrupt line is back to inactive.
432  */
433 void handle_level_irq(struct irq_desc *desc)
434 {
435 	raw_spin_lock(&desc->lock);
436 	mask_ack_irq(desc);
437 
438 	if (!irq_may_run(desc))
439 		goto out_unlock;
440 
441 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
442 	kstat_incr_irqs_this_cpu(desc);
443 
444 	/*
445 	 * If its disabled or no action available
446 	 * keep it masked and get out of here
447 	 */
448 	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
449 		desc->istate |= IRQS_PENDING;
450 		goto out_unlock;
451 	}
452 
453 	handle_irq_event(desc);
454 
455 	cond_unmask_irq(desc);
456 
457 out_unlock:
458 	raw_spin_unlock(&desc->lock);
459 }
460 EXPORT_SYMBOL_GPL(handle_level_irq);
461 
462 #ifdef CONFIG_IRQ_PREFLOW_FASTEOI
463 static inline void preflow_handler(struct irq_desc *desc)
464 {
465 	if (desc->preflow_handler)
466 		desc->preflow_handler(&desc->irq_data);
467 }
468 #else
469 static inline void preflow_handler(struct irq_desc *desc) { }
470 #endif
471 
472 static void cond_unmask_eoi_irq(struct irq_desc *desc, struct irq_chip *chip)
473 {
474 	if (!(desc->istate & IRQS_ONESHOT)) {
475 		chip->irq_eoi(&desc->irq_data);
476 		return;
477 	}
478 	/*
479 	 * We need to unmask in the following cases:
480 	 * - Oneshot irq which did not wake the thread (caused by a
481 	 *   spurious interrupt or a primary handler handling it
482 	 *   completely).
483 	 */
484 	if (!irqd_irq_disabled(&desc->irq_data) &&
485 	    irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot) {
486 		chip->irq_eoi(&desc->irq_data);
487 		unmask_irq(desc);
488 	} else if (!(chip->flags & IRQCHIP_EOI_THREADED)) {
489 		chip->irq_eoi(&desc->irq_data);
490 	}
491 }
492 
493 /**
494  *	handle_fasteoi_irq - irq handler for transparent controllers
495  *	@desc:	the interrupt description structure for this irq
496  *
497  *	Only a single callback will be issued to the chip: an ->eoi()
498  *	call when the interrupt has been serviced. This enables support
499  *	for modern forms of interrupt handlers, which handle the flow
500  *	details in hardware, transparently.
501  */
502 void handle_fasteoi_irq(struct irq_desc *desc)
503 {
504 	struct irq_chip *chip = desc->irq_data.chip;
505 
506 	raw_spin_lock(&desc->lock);
507 
508 	if (!irq_may_run(desc))
509 		goto out;
510 
511 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
512 	kstat_incr_irqs_this_cpu(desc);
513 
514 	/*
515 	 * If its disabled or no action available
516 	 * then mask it and get out of here:
517 	 */
518 	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
519 		desc->istate |= IRQS_PENDING;
520 		mask_irq(desc);
521 		goto out;
522 	}
523 
524 	if (desc->istate & IRQS_ONESHOT)
525 		mask_irq(desc);
526 
527 	preflow_handler(desc);
528 	handle_irq_event(desc);
529 
530 	cond_unmask_eoi_irq(desc, chip);
531 
532 	raw_spin_unlock(&desc->lock);
533 	return;
534 out:
535 	if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED))
536 		chip->irq_eoi(&desc->irq_data);
537 	raw_spin_unlock(&desc->lock);
538 }
539 EXPORT_SYMBOL_GPL(handle_fasteoi_irq);
540 
541 /**
542  *	handle_edge_irq - edge type IRQ handler
543  *	@desc:	the interrupt description structure for this irq
544  *
545  *	Interrupt occures on the falling and/or rising edge of a hardware
546  *	signal. The occurrence is latched into the irq controller hardware
547  *	and must be acked in order to be reenabled. After the ack another
548  *	interrupt can happen on the same source even before the first one
549  *	is handled by the associated event handler. If this happens it
550  *	might be necessary to disable (mask) the interrupt depending on the
551  *	controller hardware. This requires to reenable the interrupt inside
552  *	of the loop which handles the interrupts which have arrived while
553  *	the handler was running. If all pending interrupts are handled, the
554  *	loop is left.
555  */
556 void handle_edge_irq(struct irq_desc *desc)
557 {
558 	raw_spin_lock(&desc->lock);
559 
560 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
561 
562 	if (!irq_may_run(desc)) {
563 		desc->istate |= IRQS_PENDING;
564 		mask_ack_irq(desc);
565 		goto out_unlock;
566 	}
567 
568 	/*
569 	 * If its disabled or no action available then mask it and get
570 	 * out of here.
571 	 */
572 	if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
573 		desc->istate |= IRQS_PENDING;
574 		mask_ack_irq(desc);
575 		goto out_unlock;
576 	}
577 
578 	kstat_incr_irqs_this_cpu(desc);
579 
580 	/* Start handling the irq */
581 	desc->irq_data.chip->irq_ack(&desc->irq_data);
582 
583 	do {
584 		if (unlikely(!desc->action)) {
585 			mask_irq(desc);
586 			goto out_unlock;
587 		}
588 
589 		/*
590 		 * When another irq arrived while we were handling
591 		 * one, we could have masked the irq.
592 		 * Renable it, if it was not disabled in meantime.
593 		 */
594 		if (unlikely(desc->istate & IRQS_PENDING)) {
595 			if (!irqd_irq_disabled(&desc->irq_data) &&
596 			    irqd_irq_masked(&desc->irq_data))
597 				unmask_irq(desc);
598 		}
599 
600 		handle_irq_event(desc);
601 
602 	} while ((desc->istate & IRQS_PENDING) &&
603 		 !irqd_irq_disabled(&desc->irq_data));
604 
605 out_unlock:
606 	raw_spin_unlock(&desc->lock);
607 }
608 EXPORT_SYMBOL(handle_edge_irq);
609 
610 #ifdef CONFIG_IRQ_EDGE_EOI_HANDLER
611 /**
612  *	handle_edge_eoi_irq - edge eoi type IRQ handler
613  *	@desc:	the interrupt description structure for this irq
614  *
615  * Similar as the above handle_edge_irq, but using eoi and w/o the
616  * mask/unmask logic.
617  */
618 void handle_edge_eoi_irq(struct irq_desc *desc)
619 {
620 	struct irq_chip *chip = irq_desc_get_chip(desc);
621 
622 	raw_spin_lock(&desc->lock);
623 
624 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
625 
626 	if (!irq_may_run(desc)) {
627 		desc->istate |= IRQS_PENDING;
628 		goto out_eoi;
629 	}
630 
631 	/*
632 	 * If its disabled or no action available then mask it and get
633 	 * out of here.
634 	 */
635 	if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
636 		desc->istate |= IRQS_PENDING;
637 		goto out_eoi;
638 	}
639 
640 	kstat_incr_irqs_this_cpu(desc);
641 
642 	do {
643 		if (unlikely(!desc->action))
644 			goto out_eoi;
645 
646 		handle_irq_event(desc);
647 
648 	} while ((desc->istate & IRQS_PENDING) &&
649 		 !irqd_irq_disabled(&desc->irq_data));
650 
651 out_eoi:
652 	chip->irq_eoi(&desc->irq_data);
653 	raw_spin_unlock(&desc->lock);
654 }
655 #endif
656 
657 /**
658  *	handle_percpu_irq - Per CPU local irq handler
659  *	@desc:	the interrupt description structure for this irq
660  *
661  *	Per CPU interrupts on SMP machines without locking requirements
662  */
663 void handle_percpu_irq(struct irq_desc *desc)
664 {
665 	struct irq_chip *chip = irq_desc_get_chip(desc);
666 
667 	kstat_incr_irqs_this_cpu(desc);
668 
669 	if (chip->irq_ack)
670 		chip->irq_ack(&desc->irq_data);
671 
672 	handle_irq_event_percpu(desc, desc->action);
673 
674 	if (chip->irq_eoi)
675 		chip->irq_eoi(&desc->irq_data);
676 }
677 
678 /**
679  * handle_percpu_devid_irq - Per CPU local irq handler with per cpu dev ids
680  * @desc:	the interrupt description structure for this irq
681  *
682  * Per CPU interrupts on SMP machines without locking requirements. Same as
683  * handle_percpu_irq() above but with the following extras:
684  *
685  * action->percpu_dev_id is a pointer to percpu variables which
686  * contain the real device id for the cpu on which this handler is
687  * called
688  */
689 void handle_percpu_devid_irq(struct irq_desc *desc)
690 {
691 	struct irq_chip *chip = irq_desc_get_chip(desc);
692 	struct irqaction *action = desc->action;
693 	void *dev_id = raw_cpu_ptr(action->percpu_dev_id);
694 	unsigned int irq = irq_desc_get_irq(desc);
695 	irqreturn_t res;
696 
697 	kstat_incr_irqs_this_cpu(desc);
698 
699 	if (chip->irq_ack)
700 		chip->irq_ack(&desc->irq_data);
701 
702 	trace_irq_handler_entry(irq, action);
703 	res = action->handler(irq, dev_id);
704 	trace_irq_handler_exit(irq, action, res);
705 
706 	if (chip->irq_eoi)
707 		chip->irq_eoi(&desc->irq_data);
708 }
709 
710 void
711 __irq_do_set_handler(struct irq_desc *desc, irq_flow_handler_t handle,
712 		     int is_chained, const char *name)
713 {
714 	if (!handle) {
715 		handle = handle_bad_irq;
716 	} else {
717 		struct irq_data *irq_data = &desc->irq_data;
718 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
719 		/*
720 		 * With hierarchical domains we might run into a
721 		 * situation where the outermost chip is not yet set
722 		 * up, but the inner chips are there.  Instead of
723 		 * bailing we install the handler, but obviously we
724 		 * cannot enable/startup the interrupt at this point.
725 		 */
726 		while (irq_data) {
727 			if (irq_data->chip != &no_irq_chip)
728 				break;
729 			/*
730 			 * Bail out if the outer chip is not set up
731 			 * and the interrrupt supposed to be started
732 			 * right away.
733 			 */
734 			if (WARN_ON(is_chained))
735 				return;
736 			/* Try the parent */
737 			irq_data = irq_data->parent_data;
738 		}
739 #endif
740 		if (WARN_ON(!irq_data || irq_data->chip == &no_irq_chip))
741 			return;
742 	}
743 
744 	/* Uninstall? */
745 	if (handle == handle_bad_irq) {
746 		if (desc->irq_data.chip != &no_irq_chip)
747 			mask_ack_irq(desc);
748 		irq_state_set_disabled(desc);
749 		desc->depth = 1;
750 	}
751 	desc->handle_irq = handle;
752 	desc->name = name;
753 
754 	if (handle != handle_bad_irq && is_chained) {
755 		irq_settings_set_noprobe(desc);
756 		irq_settings_set_norequest(desc);
757 		irq_settings_set_nothread(desc);
758 		irq_startup(desc, true);
759 	}
760 }
761 
762 void
763 __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
764 		  const char *name)
765 {
766 	unsigned long flags;
767 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
768 
769 	if (!desc)
770 		return;
771 
772 	__irq_do_set_handler(desc, handle, is_chained, name);
773 	irq_put_desc_busunlock(desc, flags);
774 }
775 EXPORT_SYMBOL_GPL(__irq_set_handler);
776 
777 void
778 irq_set_chained_handler_and_data(unsigned int irq, irq_flow_handler_t handle,
779 				 void *data)
780 {
781 	unsigned long flags;
782 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
783 
784 	if (!desc)
785 		return;
786 
787 	__irq_do_set_handler(desc, handle, 1, NULL);
788 	desc->irq_common_data.handler_data = data;
789 
790 	irq_put_desc_busunlock(desc, flags);
791 }
792 EXPORT_SYMBOL_GPL(irq_set_chained_handler_and_data);
793 
794 void
795 irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
796 			      irq_flow_handler_t handle, const char *name)
797 {
798 	irq_set_chip(irq, chip);
799 	__irq_set_handler(irq, handle, 0, name);
800 }
801 EXPORT_SYMBOL_GPL(irq_set_chip_and_handler_name);
802 
803 void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
804 {
805 	unsigned long flags;
806 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
807 
808 	if (!desc)
809 		return;
810 	irq_settings_clr_and_set(desc, clr, set);
811 
812 	irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU |
813 		   IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT);
814 	if (irq_settings_has_no_balance_set(desc))
815 		irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
816 	if (irq_settings_is_per_cpu(desc))
817 		irqd_set(&desc->irq_data, IRQD_PER_CPU);
818 	if (irq_settings_can_move_pcntxt(desc))
819 		irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT);
820 	if (irq_settings_is_level(desc))
821 		irqd_set(&desc->irq_data, IRQD_LEVEL);
822 
823 	irqd_set(&desc->irq_data, irq_settings_get_trigger_mask(desc));
824 
825 	irq_put_desc_unlock(desc, flags);
826 }
827 EXPORT_SYMBOL_GPL(irq_modify_status);
828 
829 /**
830  *	irq_cpu_online - Invoke all irq_cpu_online functions.
831  *
832  *	Iterate through all irqs and invoke the chip.irq_cpu_online()
833  *	for each.
834  */
835 void irq_cpu_online(void)
836 {
837 	struct irq_desc *desc;
838 	struct irq_chip *chip;
839 	unsigned long flags;
840 	unsigned int irq;
841 
842 	for_each_active_irq(irq) {
843 		desc = irq_to_desc(irq);
844 		if (!desc)
845 			continue;
846 
847 		raw_spin_lock_irqsave(&desc->lock, flags);
848 
849 		chip = irq_data_get_irq_chip(&desc->irq_data);
850 		if (chip && chip->irq_cpu_online &&
851 		    (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
852 		     !irqd_irq_disabled(&desc->irq_data)))
853 			chip->irq_cpu_online(&desc->irq_data);
854 
855 		raw_spin_unlock_irqrestore(&desc->lock, flags);
856 	}
857 }
858 
859 /**
860  *	irq_cpu_offline - Invoke all irq_cpu_offline functions.
861  *
862  *	Iterate through all irqs and invoke the chip.irq_cpu_offline()
863  *	for each.
864  */
865 void irq_cpu_offline(void)
866 {
867 	struct irq_desc *desc;
868 	struct irq_chip *chip;
869 	unsigned long flags;
870 	unsigned int irq;
871 
872 	for_each_active_irq(irq) {
873 		desc = irq_to_desc(irq);
874 		if (!desc)
875 			continue;
876 
877 		raw_spin_lock_irqsave(&desc->lock, flags);
878 
879 		chip = irq_data_get_irq_chip(&desc->irq_data);
880 		if (chip && chip->irq_cpu_offline &&
881 		    (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
882 		     !irqd_irq_disabled(&desc->irq_data)))
883 			chip->irq_cpu_offline(&desc->irq_data);
884 
885 		raw_spin_unlock_irqrestore(&desc->lock, flags);
886 	}
887 }
888 
889 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
890 /**
891  * irq_chip_enable_parent - Enable the parent interrupt (defaults to unmask if
892  * NULL)
893  * @data:	Pointer to interrupt specific data
894  */
895 void irq_chip_enable_parent(struct irq_data *data)
896 {
897 	data = data->parent_data;
898 	if (data->chip->irq_enable)
899 		data->chip->irq_enable(data);
900 	else
901 		data->chip->irq_unmask(data);
902 }
903 
904 /**
905  * irq_chip_disable_parent - Disable the parent interrupt (defaults to mask if
906  * NULL)
907  * @data:	Pointer to interrupt specific data
908  */
909 void irq_chip_disable_parent(struct irq_data *data)
910 {
911 	data = data->parent_data;
912 	if (data->chip->irq_disable)
913 		data->chip->irq_disable(data);
914 	else
915 		data->chip->irq_mask(data);
916 }
917 
918 /**
919  * irq_chip_ack_parent - Acknowledge the parent interrupt
920  * @data:	Pointer to interrupt specific data
921  */
922 void irq_chip_ack_parent(struct irq_data *data)
923 {
924 	data = data->parent_data;
925 	data->chip->irq_ack(data);
926 }
927 
928 /**
929  * irq_chip_mask_parent - Mask the parent interrupt
930  * @data:	Pointer to interrupt specific data
931  */
932 void irq_chip_mask_parent(struct irq_data *data)
933 {
934 	data = data->parent_data;
935 	data->chip->irq_mask(data);
936 }
937 
938 /**
939  * irq_chip_unmask_parent - Unmask the parent interrupt
940  * @data:	Pointer to interrupt specific data
941  */
942 void irq_chip_unmask_parent(struct irq_data *data)
943 {
944 	data = data->parent_data;
945 	data->chip->irq_unmask(data);
946 }
947 
948 /**
949  * irq_chip_eoi_parent - Invoke EOI on the parent interrupt
950  * @data:	Pointer to interrupt specific data
951  */
952 void irq_chip_eoi_parent(struct irq_data *data)
953 {
954 	data = data->parent_data;
955 	data->chip->irq_eoi(data);
956 }
957 
958 /**
959  * irq_chip_set_affinity_parent - Set affinity on the parent interrupt
960  * @data:	Pointer to interrupt specific data
961  * @dest:	The affinity mask to set
962  * @force:	Flag to enforce setting (disable online checks)
963  *
964  * Conditinal, as the underlying parent chip might not implement it.
965  */
966 int irq_chip_set_affinity_parent(struct irq_data *data,
967 				 const struct cpumask *dest, bool force)
968 {
969 	data = data->parent_data;
970 	if (data->chip->irq_set_affinity)
971 		return data->chip->irq_set_affinity(data, dest, force);
972 
973 	return -ENOSYS;
974 }
975 
976 /**
977  * irq_chip_set_type_parent - Set IRQ type on the parent interrupt
978  * @data:	Pointer to interrupt specific data
979  * @type:	IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
980  *
981  * Conditional, as the underlying parent chip might not implement it.
982  */
983 int irq_chip_set_type_parent(struct irq_data *data, unsigned int type)
984 {
985 	data = data->parent_data;
986 
987 	if (data->chip->irq_set_type)
988 		return data->chip->irq_set_type(data, type);
989 
990 	return -ENOSYS;
991 }
992 
993 /**
994  * irq_chip_retrigger_hierarchy - Retrigger an interrupt in hardware
995  * @data:	Pointer to interrupt specific data
996  *
997  * Iterate through the domain hierarchy of the interrupt and check
998  * whether a hw retrigger function exists. If yes, invoke it.
999  */
1000 int irq_chip_retrigger_hierarchy(struct irq_data *data)
1001 {
1002 	for (data = data->parent_data; data; data = data->parent_data)
1003 		if (data->chip && data->chip->irq_retrigger)
1004 			return data->chip->irq_retrigger(data);
1005 
1006 	return 0;
1007 }
1008 
1009 /**
1010  * irq_chip_set_vcpu_affinity_parent - Set vcpu affinity on the parent interrupt
1011  * @data:	Pointer to interrupt specific data
1012  * @vcpu_info:	The vcpu affinity information
1013  */
1014 int irq_chip_set_vcpu_affinity_parent(struct irq_data *data, void *vcpu_info)
1015 {
1016 	data = data->parent_data;
1017 	if (data->chip->irq_set_vcpu_affinity)
1018 		return data->chip->irq_set_vcpu_affinity(data, vcpu_info);
1019 
1020 	return -ENOSYS;
1021 }
1022 
1023 /**
1024  * irq_chip_set_wake_parent - Set/reset wake-up on the parent interrupt
1025  * @data:	Pointer to interrupt specific data
1026  * @on:		Whether to set or reset the wake-up capability of this irq
1027  *
1028  * Conditional, as the underlying parent chip might not implement it.
1029  */
1030 int irq_chip_set_wake_parent(struct irq_data *data, unsigned int on)
1031 {
1032 	data = data->parent_data;
1033 	if (data->chip->irq_set_wake)
1034 		return data->chip->irq_set_wake(data, on);
1035 
1036 	return -ENOSYS;
1037 }
1038 #endif
1039 
1040 /**
1041  * irq_chip_compose_msi_msg - Componse msi message for a irq chip
1042  * @data:	Pointer to interrupt specific data
1043  * @msg:	Pointer to the MSI message
1044  *
1045  * For hierarchical domains we find the first chip in the hierarchy
1046  * which implements the irq_compose_msi_msg callback. For non
1047  * hierarchical we use the top level chip.
1048  */
1049 int irq_chip_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
1050 {
1051 	struct irq_data *pos = NULL;
1052 
1053 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
1054 	for (; data; data = data->parent_data)
1055 #endif
1056 		if (data->chip && data->chip->irq_compose_msi_msg)
1057 			pos = data;
1058 	if (!pos)
1059 		return -ENOSYS;
1060 
1061 	pos->chip->irq_compose_msi_msg(pos, msg);
1062 
1063 	return 0;
1064 }
1065