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v4.6
   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
  24static irqreturn_t bad_chained_irq(int irq, void *dev_id)
  25{
  26	WARN_ONCE(1, "Chained irq %d should not call an action\n", irq);
  27	return IRQ_NONE;
  28}
  29
  30/*
  31 * Chained handlers should never call action on their IRQ. This default
  32 * action will emit warning if such thing happens.
  33 */
  34struct irqaction chained_action = {
  35	.handler = bad_chained_irq,
  36};
  37
  38/**
  39 *	irq_set_chip - set the irq chip for an irq
  40 *	@irq:	irq number
  41 *	@chip:	pointer to irq chip description structure
  42 */
  43int irq_set_chip(unsigned int irq, struct irq_chip *chip)
  44{
  45	unsigned long flags;
  46	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
  47
  48	if (!desc)
  49		return -EINVAL;
  50
  51	if (!chip)
  52		chip = &no_irq_chip;
  53
  54	desc->irq_data.chip = chip;
  55	irq_put_desc_unlock(desc, flags);
  56	/*
  57	 * For !CONFIG_SPARSE_IRQ make the irq show up in
  58	 * allocated_irqs.
 
  59	 */
  60	irq_mark_irq(irq);
  61	return 0;
  62}
  63EXPORT_SYMBOL(irq_set_chip);
  64
  65/**
  66 *	irq_set_type - set the irq trigger type for an irq
  67 *	@irq:	irq number
  68 *	@type:	IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
  69 */
  70int irq_set_irq_type(unsigned int irq, unsigned int type)
  71{
  72	unsigned long flags;
  73	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
  74	int ret = 0;
  75
  76	if (!desc)
  77		return -EINVAL;
  78
  79	type &= IRQ_TYPE_SENSE_MASK;
  80	ret = __irq_set_trigger(desc, type);
 
  81	irq_put_desc_busunlock(desc, flags);
  82	return ret;
  83}
  84EXPORT_SYMBOL(irq_set_irq_type);
  85
  86/**
  87 *	irq_set_handler_data - set irq handler data for an irq
  88 *	@irq:	Interrupt number
  89 *	@data:	Pointer to interrupt specific data
  90 *
  91 *	Set the hardware irq controller data for an irq
  92 */
  93int irq_set_handler_data(unsigned int irq, void *data)
  94{
  95	unsigned long flags;
  96	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
  97
  98	if (!desc)
  99		return -EINVAL;
 100	desc->irq_common_data.handler_data = data;
 101	irq_put_desc_unlock(desc, flags);
 102	return 0;
 103}
 104EXPORT_SYMBOL(irq_set_handler_data);
 105
 106/**
 107 *	irq_set_msi_desc_off - set MSI descriptor data for an irq at offset
 108 *	@irq_base:	Interrupt number base
 109 *	@irq_offset:	Interrupt number offset
 110 *	@entry:		Pointer to MSI descriptor data
 111 *
 112 *	Set the MSI descriptor entry for an irq at offset
 113 */
 114int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset,
 115			 struct msi_desc *entry)
 116{
 117	unsigned long flags;
 118	struct irq_desc *desc = irq_get_desc_lock(irq_base + irq_offset, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
 119
 120	if (!desc)
 121		return -EINVAL;
 122	desc->irq_common_data.msi_desc = entry;
 123	if (entry && !irq_offset)
 124		entry->irq = irq_base;
 125	irq_put_desc_unlock(desc, flags);
 126	return 0;
 127}
 128
 129/**
 130 *	irq_set_msi_desc - set MSI descriptor data for an irq
 131 *	@irq:	Interrupt number
 132 *	@entry:	Pointer to MSI descriptor data
 133 *
 134 *	Set the MSI descriptor entry for an irq
 135 */
 136int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry)
 137{
 138	return irq_set_msi_desc_off(irq, 0, entry);
 139}
 140
 141/**
 142 *	irq_set_chip_data - set irq chip data for an irq
 143 *	@irq:	Interrupt number
 144 *	@data:	Pointer to chip specific data
 145 *
 146 *	Set the hardware irq chip data for an irq
 147 */
 148int irq_set_chip_data(unsigned int irq, void *data)
 149{
 150	unsigned long flags;
 151	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
 152
 153	if (!desc)
 154		return -EINVAL;
 155	desc->irq_data.chip_data = data;
 156	irq_put_desc_unlock(desc, flags);
 157	return 0;
 158}
 159EXPORT_SYMBOL(irq_set_chip_data);
 160
 161struct irq_data *irq_get_irq_data(unsigned int irq)
 162{
 163	struct irq_desc *desc = irq_to_desc(irq);
 164
 165	return desc ? &desc->irq_data : NULL;
 166}
 167EXPORT_SYMBOL_GPL(irq_get_irq_data);
 168
 169static void irq_state_clr_disabled(struct irq_desc *desc)
 170{
 171	irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED);
 172}
 173
 174static void irq_state_set_disabled(struct irq_desc *desc)
 175{
 176	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
 177}
 178
 179static void irq_state_clr_masked(struct irq_desc *desc)
 180{
 181	irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED);
 182}
 183
 184static void irq_state_set_masked(struct irq_desc *desc)
 185{
 186	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
 187}
 188
 189int irq_startup(struct irq_desc *desc, bool resend)
 190{
 191	int ret = 0;
 192
 193	irq_state_clr_disabled(desc);
 194	desc->depth = 0;
 195
 196	irq_domain_activate_irq(&desc->irq_data);
 197	if (desc->irq_data.chip->irq_startup) {
 198		ret = desc->irq_data.chip->irq_startup(&desc->irq_data);
 199		irq_state_clr_masked(desc);
 200	} else {
 201		irq_enable(desc);
 202	}
 203	if (resend)
 204		check_irq_resend(desc);
 205	return ret;
 206}
 207
 208void irq_shutdown(struct irq_desc *desc)
 209{
 210	irq_state_set_disabled(desc);
 211	desc->depth = 1;
 212	if (desc->irq_data.chip->irq_shutdown)
 213		desc->irq_data.chip->irq_shutdown(&desc->irq_data);
 214	else if (desc->irq_data.chip->irq_disable)
 215		desc->irq_data.chip->irq_disable(&desc->irq_data);
 216	else
 217		desc->irq_data.chip->irq_mask(&desc->irq_data);
 218	irq_domain_deactivate_irq(&desc->irq_data);
 219	irq_state_set_masked(desc);
 220}
 221
 222void irq_enable(struct irq_desc *desc)
 223{
 224	irq_state_clr_disabled(desc);
 225	if (desc->irq_data.chip->irq_enable)
 226		desc->irq_data.chip->irq_enable(&desc->irq_data);
 227	else
 228		desc->irq_data.chip->irq_unmask(&desc->irq_data);
 229	irq_state_clr_masked(desc);
 230}
 231
 232/**
 233 * irq_disable - Mark interrupt disabled
 234 * @desc:	irq descriptor which should be disabled
 235 *
 236 * If the chip does not implement the irq_disable callback, we
 237 * use a lazy disable approach. That means we mark the interrupt
 238 * disabled, but leave the hardware unmasked. That's an
 239 * optimization because we avoid the hardware access for the
 240 * common case where no interrupt happens after we marked it
 241 * disabled. If an interrupt happens, then the interrupt flow
 242 * handler masks the line at the hardware level and marks it
 243 * pending.
 244 *
 245 * If the interrupt chip does not implement the irq_disable callback,
 246 * a driver can disable the lazy approach for a particular irq line by
 247 * calling 'irq_set_status_flags(irq, IRQ_DISABLE_UNLAZY)'. This can
 248 * be used for devices which cannot disable the interrupt at the
 249 * device level under certain circumstances and have to use
 250 * disable_irq[_nosync] instead.
 251 */
 252void irq_disable(struct irq_desc *desc)
 253{
 254	irq_state_set_disabled(desc);
 255	if (desc->irq_data.chip->irq_disable) {
 256		desc->irq_data.chip->irq_disable(&desc->irq_data);
 257		irq_state_set_masked(desc);
 258	} else if (irq_settings_disable_unlazy(desc)) {
 259		mask_irq(desc);
 260	}
 261}
 262
 263void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu)
 264{
 265	if (desc->irq_data.chip->irq_enable)
 266		desc->irq_data.chip->irq_enable(&desc->irq_data);
 267	else
 268		desc->irq_data.chip->irq_unmask(&desc->irq_data);
 269	cpumask_set_cpu(cpu, desc->percpu_enabled);
 270}
 271
 272void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu)
 273{
 274	if (desc->irq_data.chip->irq_disable)
 275		desc->irq_data.chip->irq_disable(&desc->irq_data);
 276	else
 277		desc->irq_data.chip->irq_mask(&desc->irq_data);
 278	cpumask_clear_cpu(cpu, desc->percpu_enabled);
 279}
 280
 281static inline void mask_ack_irq(struct irq_desc *desc)
 282{
 283	if (desc->irq_data.chip->irq_mask_ack)
 284		desc->irq_data.chip->irq_mask_ack(&desc->irq_data);
 285	else {
 286		desc->irq_data.chip->irq_mask(&desc->irq_data);
 287		if (desc->irq_data.chip->irq_ack)
 288			desc->irq_data.chip->irq_ack(&desc->irq_data);
 289	}
 290	irq_state_set_masked(desc);
 291}
 292
 293void mask_irq(struct irq_desc *desc)
 294{
 295	if (desc->irq_data.chip->irq_mask) {
 296		desc->irq_data.chip->irq_mask(&desc->irq_data);
 297		irq_state_set_masked(desc);
 298	}
 299}
 300
 301void unmask_irq(struct irq_desc *desc)
 302{
 303	if (desc->irq_data.chip->irq_unmask) {
 304		desc->irq_data.chip->irq_unmask(&desc->irq_data);
 305		irq_state_clr_masked(desc);
 306	}
 307}
 308
 309void unmask_threaded_irq(struct irq_desc *desc)
 310{
 311	struct irq_chip *chip = desc->irq_data.chip;
 312
 313	if (chip->flags & IRQCHIP_EOI_THREADED)
 314		chip->irq_eoi(&desc->irq_data);
 315
 316	if (chip->irq_unmask) {
 317		chip->irq_unmask(&desc->irq_data);
 318		irq_state_clr_masked(desc);
 319	}
 320}
 321
 322/*
 323 *	handle_nested_irq - Handle a nested irq from a irq thread
 324 *	@irq:	the interrupt number
 325 *
 326 *	Handle interrupts which are nested into a threaded interrupt
 327 *	handler. The handler function is called inside the calling
 328 *	threads context.
 329 */
 330void handle_nested_irq(unsigned int irq)
 331{
 332	struct irq_desc *desc = irq_to_desc(irq);
 333	struct irqaction *action;
 334	irqreturn_t action_ret;
 335
 336	might_sleep();
 337
 338	raw_spin_lock_irq(&desc->lock);
 339
 340	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 341
 342	action = desc->action;
 343	if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) {
 344		desc->istate |= IRQS_PENDING;
 345		goto out_unlock;
 346	}
 347
 348	kstat_incr_irqs_this_cpu(desc);
 349	irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
 350	raw_spin_unlock_irq(&desc->lock);
 351
 352	action_ret = action->thread_fn(action->irq, action->dev_id);
 353	if (!noirqdebug)
 354		note_interrupt(desc, action_ret);
 355
 356	raw_spin_lock_irq(&desc->lock);
 357	irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
 358
 359out_unlock:
 360	raw_spin_unlock_irq(&desc->lock);
 361}
 362EXPORT_SYMBOL_GPL(handle_nested_irq);
 363
 364static bool irq_check_poll(struct irq_desc *desc)
 365{
 366	if (!(desc->istate & IRQS_POLL_INPROGRESS))
 367		return false;
 368	return irq_wait_for_poll(desc);
 369}
 370
 371static bool irq_may_run(struct irq_desc *desc)
 372{
 373	unsigned int mask = IRQD_IRQ_INPROGRESS | IRQD_WAKEUP_ARMED;
 374
 375	/*
 376	 * If the interrupt is not in progress and is not an armed
 377	 * wakeup interrupt, proceed.
 378	 */
 379	if (!irqd_has_set(&desc->irq_data, mask))
 380		return true;
 381
 382	/*
 383	 * If the interrupt is an armed wakeup source, mark it pending
 384	 * and suspended, disable it and notify the pm core about the
 385	 * event.
 386	 */
 387	if (irq_pm_check_wakeup(desc))
 388		return false;
 389
 390	/*
 391	 * Handle a potential concurrent poll on a different core.
 392	 */
 393	return irq_check_poll(desc);
 394}
 395
 396/**
 397 *	handle_simple_irq - Simple and software-decoded IRQs.
 
 398 *	@desc:	the interrupt description structure for this irq
 399 *
 400 *	Simple interrupts are either sent from a demultiplexing interrupt
 401 *	handler or come from hardware, where no interrupt hardware control
 402 *	is necessary.
 403 *
 404 *	Note: The caller is expected to handle the ack, clear, mask and
 405 *	unmask issues if necessary.
 406 */
 407void handle_simple_irq(struct irq_desc *desc)
 
 408{
 409	raw_spin_lock(&desc->lock);
 410
 411	if (!irq_may_run(desc))
 412		goto out_unlock;
 
 413
 414	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 
 415
 416	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
 417		desc->istate |= IRQS_PENDING;
 418		goto out_unlock;
 419	}
 420
 421	kstat_incr_irqs_this_cpu(desc);
 422	handle_irq_event(desc);
 423
 424out_unlock:
 425	raw_spin_unlock(&desc->lock);
 426}
 427EXPORT_SYMBOL_GPL(handle_simple_irq);
 428
 429/*
 430 * Called unconditionally from handle_level_irq() and only for oneshot
 431 * interrupts from handle_fasteoi_irq()
 432 */
 433static void cond_unmask_irq(struct irq_desc *desc)
 434{
 435	/*
 436	 * We need to unmask in the following cases:
 437	 * - Standard level irq (IRQF_ONESHOT is not set)
 438	 * - Oneshot irq which did not wake the thread (caused by a
 439	 *   spurious interrupt or a primary handler handling it
 440	 *   completely).
 441	 */
 442	if (!irqd_irq_disabled(&desc->irq_data) &&
 443	    irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot)
 444		unmask_irq(desc);
 445}
 446
 447/**
 448 *	handle_level_irq - Level type irq handler
 
 449 *	@desc:	the interrupt description structure for this irq
 450 *
 451 *	Level type interrupts are active as long as the hardware line has
 452 *	the active level. This may require to mask the interrupt and unmask
 453 *	it after the associated handler has acknowledged the device, so the
 454 *	interrupt line is back to inactive.
 455 */
 456void handle_level_irq(struct irq_desc *desc)
 
 457{
 458	raw_spin_lock(&desc->lock);
 459	mask_ack_irq(desc);
 460
 461	if (!irq_may_run(desc))
 462		goto out_unlock;
 
 463
 464	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 
 465
 466	/*
 467	 * If its disabled or no action available
 468	 * keep it masked and get out of here
 469	 */
 470	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
 471		desc->istate |= IRQS_PENDING;
 472		goto out_unlock;
 473	}
 474
 475	kstat_incr_irqs_this_cpu(desc);
 476	handle_irq_event(desc);
 477
 478	cond_unmask_irq(desc);
 479
 480out_unlock:
 481	raw_spin_unlock(&desc->lock);
 482}
 483EXPORT_SYMBOL_GPL(handle_level_irq);
 484
 485#ifdef CONFIG_IRQ_PREFLOW_FASTEOI
 486static inline void preflow_handler(struct irq_desc *desc)
 487{
 488	if (desc->preflow_handler)
 489		desc->preflow_handler(&desc->irq_data);
 490}
 491#else
 492static inline void preflow_handler(struct irq_desc *desc) { }
 493#endif
 494
 495static void cond_unmask_eoi_irq(struct irq_desc *desc, struct irq_chip *chip)
 496{
 497	if (!(desc->istate & IRQS_ONESHOT)) {
 498		chip->irq_eoi(&desc->irq_data);
 499		return;
 500	}
 501	/*
 502	 * We need to unmask in the following cases:
 503	 * - Oneshot irq which did not wake the thread (caused by a
 504	 *   spurious interrupt or a primary handler handling it
 505	 *   completely).
 506	 */
 507	if (!irqd_irq_disabled(&desc->irq_data) &&
 508	    irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot) {
 509		chip->irq_eoi(&desc->irq_data);
 510		unmask_irq(desc);
 511	} else if (!(chip->flags & IRQCHIP_EOI_THREADED)) {
 512		chip->irq_eoi(&desc->irq_data);
 513	}
 514}
 515
 516/**
 517 *	handle_fasteoi_irq - irq handler for transparent controllers
 
 518 *	@desc:	the interrupt description structure for this irq
 519 *
 520 *	Only a single callback will be issued to the chip: an ->eoi()
 521 *	call when the interrupt has been serviced. This enables support
 522 *	for modern forms of interrupt handlers, which handle the flow
 523 *	details in hardware, transparently.
 524 */
 525void handle_fasteoi_irq(struct irq_desc *desc)
 
 526{
 527	struct irq_chip *chip = desc->irq_data.chip;
 528
 529	raw_spin_lock(&desc->lock);
 530
 531	if (!irq_may_run(desc))
 532		goto out;
 
 533
 534	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 
 535
 536	/*
 537	 * If its disabled or no action available
 538	 * then mask it and get out of here:
 539	 */
 540	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
 541		desc->istate |= IRQS_PENDING;
 542		mask_irq(desc);
 543		goto out;
 544	}
 545
 546	kstat_incr_irqs_this_cpu(desc);
 547	if (desc->istate & IRQS_ONESHOT)
 548		mask_irq(desc);
 549
 550	preflow_handler(desc);
 551	handle_irq_event(desc);
 552
 553	cond_unmask_eoi_irq(desc, chip);
 554
 
 555	raw_spin_unlock(&desc->lock);
 556	return;
 557out:
 558	if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED))
 559		chip->irq_eoi(&desc->irq_data);
 560	raw_spin_unlock(&desc->lock);
 561}
 562EXPORT_SYMBOL_GPL(handle_fasteoi_irq);
 563
 564/**
 565 *	handle_edge_irq - edge type IRQ handler
 
 566 *	@desc:	the interrupt description structure for this irq
 567 *
 568 *	Interrupt occures on the falling and/or rising edge of a hardware
 569 *	signal. The occurrence is latched into the irq controller hardware
 570 *	and must be acked in order to be reenabled. After the ack another
 571 *	interrupt can happen on the same source even before the first one
 572 *	is handled by the associated event handler. If this happens it
 573 *	might be necessary to disable (mask) the interrupt depending on the
 574 *	controller hardware. This requires to reenable the interrupt inside
 575 *	of the loop which handles the interrupts which have arrived while
 576 *	the handler was running. If all pending interrupts are handled, the
 577 *	loop is left.
 578 */
 579void handle_edge_irq(struct irq_desc *desc)
 
 580{
 581	raw_spin_lock(&desc->lock);
 582
 583	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 584
 585	if (!irq_may_run(desc)) {
 586		desc->istate |= IRQS_PENDING;
 587		mask_ack_irq(desc);
 588		goto out_unlock;
 589	}
 590
 591	/*
 592	 * If its disabled or no action available then mask it and get
 593	 * out of here.
 
 594	 */
 595	if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
 596		desc->istate |= IRQS_PENDING;
 597		mask_ack_irq(desc);
 598		goto out_unlock;
 
 
 
 599	}
 600
 601	kstat_incr_irqs_this_cpu(desc);
 602
 603	/* Start handling the irq */
 604	desc->irq_data.chip->irq_ack(&desc->irq_data);
 605
 606	do {
 607		if (unlikely(!desc->action)) {
 608			mask_irq(desc);
 609			goto out_unlock;
 610		}
 611
 612		/*
 613		 * When another irq arrived while we were handling
 614		 * one, we could have masked the irq.
 615		 * Renable it, if it was not disabled in meantime.
 616		 */
 617		if (unlikely(desc->istate & IRQS_PENDING)) {
 618			if (!irqd_irq_disabled(&desc->irq_data) &&
 619			    irqd_irq_masked(&desc->irq_data))
 620				unmask_irq(desc);
 621		}
 622
 623		handle_irq_event(desc);
 624
 625	} while ((desc->istate & IRQS_PENDING) &&
 626		 !irqd_irq_disabled(&desc->irq_data));
 627
 628out_unlock:
 629	raw_spin_unlock(&desc->lock);
 630}
 631EXPORT_SYMBOL(handle_edge_irq);
 632
 633#ifdef CONFIG_IRQ_EDGE_EOI_HANDLER
 634/**
 635 *	handle_edge_eoi_irq - edge eoi type IRQ handler
 
 636 *	@desc:	the interrupt description structure for this irq
 637 *
 638 * Similar as the above handle_edge_irq, but using eoi and w/o the
 639 * mask/unmask logic.
 640 */
 641void handle_edge_eoi_irq(struct irq_desc *desc)
 642{
 643	struct irq_chip *chip = irq_desc_get_chip(desc);
 644
 645	raw_spin_lock(&desc->lock);
 646
 647	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 648
 649	if (!irq_may_run(desc)) {
 650		desc->istate |= IRQS_PENDING;
 651		goto out_eoi;
 652	}
 653
 654	/*
 655	 * If its disabled or no action available then mask it and get
 656	 * out of here.
 
 657	 */
 658	if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
 659		desc->istate |= IRQS_PENDING;
 660		goto out_eoi;
 
 
 
 661	}
 662
 663	kstat_incr_irqs_this_cpu(desc);
 664
 665	do {
 666		if (unlikely(!desc->action))
 667			goto out_eoi;
 668
 669		handle_irq_event(desc);
 670
 671	} while ((desc->istate & IRQS_PENDING) &&
 672		 !irqd_irq_disabled(&desc->irq_data));
 673
 674out_eoi:
 675	chip->irq_eoi(&desc->irq_data);
 676	raw_spin_unlock(&desc->lock);
 677}
 678#endif
 679
 680/**
 681 *	handle_percpu_irq - Per CPU local irq handler
 
 682 *	@desc:	the interrupt description structure for this irq
 683 *
 684 *	Per CPU interrupts on SMP machines without locking requirements
 685 */
 686void handle_percpu_irq(struct irq_desc *desc)
 
 687{
 688	struct irq_chip *chip = irq_desc_get_chip(desc);
 689
 690	kstat_incr_irqs_this_cpu(desc);
 691
 692	if (chip->irq_ack)
 693		chip->irq_ack(&desc->irq_data);
 694
 695	handle_irq_event_percpu(desc);
 696
 697	if (chip->irq_eoi)
 698		chip->irq_eoi(&desc->irq_data);
 699}
 700
 701/**
 702 * handle_percpu_devid_irq - Per CPU local irq handler with per cpu dev ids
 703 * @desc:	the interrupt description structure for this irq
 704 *
 705 * Per CPU interrupts on SMP machines without locking requirements. Same as
 706 * handle_percpu_irq() above but with the following extras:
 707 *
 708 * action->percpu_dev_id is a pointer to percpu variables which
 709 * contain the real device id for the cpu on which this handler is
 710 * called
 711 */
 712void handle_percpu_devid_irq(struct irq_desc *desc)
 713{
 714	struct irq_chip *chip = irq_desc_get_chip(desc);
 715	struct irqaction *action = desc->action;
 716	void *dev_id = raw_cpu_ptr(action->percpu_dev_id);
 717	unsigned int irq = irq_desc_get_irq(desc);
 718	irqreturn_t res;
 719
 720	kstat_incr_irqs_this_cpu(desc);
 721
 722	if (chip->irq_ack)
 723		chip->irq_ack(&desc->irq_data);
 724
 725	trace_irq_handler_entry(irq, action);
 726	res = action->handler(irq, dev_id);
 727	trace_irq_handler_exit(irq, action, res);
 728
 729	if (chip->irq_eoi)
 730		chip->irq_eoi(&desc->irq_data);
 731}
 732
 733void
 734__irq_do_set_handler(struct irq_desc *desc, irq_flow_handler_t handle,
 735		     int is_chained, const char *name)
 736{
 737	if (!handle) {
 738		handle = handle_bad_irq;
 739	} else {
 740		struct irq_data *irq_data = &desc->irq_data;
 741#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
 742		/*
 743		 * With hierarchical domains we might run into a
 744		 * situation where the outermost chip is not yet set
 745		 * up, but the inner chips are there.  Instead of
 746		 * bailing we install the handler, but obviously we
 747		 * cannot enable/startup the interrupt at this point.
 748		 */
 749		while (irq_data) {
 750			if (irq_data->chip != &no_irq_chip)
 751				break;
 752			/*
 753			 * Bail out if the outer chip is not set up
 754			 * and the interrrupt supposed to be started
 755			 * right away.
 756			 */
 757			if (WARN_ON(is_chained))
 758				return;
 759			/* Try the parent */
 760			irq_data = irq_data->parent_data;
 761		}
 762#endif
 763		if (WARN_ON(!irq_data || irq_data->chip == &no_irq_chip))
 764			return;
 765	}
 766
 767	/* Uninstall? */
 768	if (handle == handle_bad_irq) {
 769		if (desc->irq_data.chip != &no_irq_chip)
 770			mask_ack_irq(desc);
 771		irq_state_set_disabled(desc);
 772		if (is_chained)
 773			desc->action = NULL;
 774		desc->depth = 1;
 775	}
 776	desc->handle_irq = handle;
 777	desc->name = name;
 778
 779	if (handle != handle_bad_irq && is_chained) {
 780		irq_settings_set_noprobe(desc);
 781		irq_settings_set_norequest(desc);
 782		irq_settings_set_nothread(desc);
 783		desc->action = &chained_action;
 784		irq_startup(desc, true);
 785	}
 786}
 787
 788void
 789__irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 790		  const char *name)
 791{
 792	unsigned long flags;
 793	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
 794
 795	if (!desc)
 796		return;
 797
 798	__irq_do_set_handler(desc, handle, is_chained, name);
 799	irq_put_desc_busunlock(desc, flags);
 800}
 801EXPORT_SYMBOL_GPL(__irq_set_handler);
 802
 803void
 804irq_set_chained_handler_and_data(unsigned int irq, irq_flow_handler_t handle,
 805				 void *data)
 806{
 807	unsigned long flags;
 808	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
 809
 810	if (!desc)
 811		return;
 812
 813	__irq_do_set_handler(desc, handle, 1, NULL);
 814	desc->irq_common_data.handler_data = data;
 815
 816	irq_put_desc_busunlock(desc, flags);
 817}
 818EXPORT_SYMBOL_GPL(irq_set_chained_handler_and_data);
 819
 820void
 821irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
 822			      irq_flow_handler_t handle, const char *name)
 823{
 824	irq_set_chip(irq, chip);
 825	__irq_set_handler(irq, handle, 0, name);
 826}
 827EXPORT_SYMBOL_GPL(irq_set_chip_and_handler_name);
 828
 829void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
 830{
 831	unsigned long flags;
 832	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
 833
 834	if (!desc)
 835		return;
 836	irq_settings_clr_and_set(desc, clr, set);
 837
 838	irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU |
 839		   IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT);
 840	if (irq_settings_has_no_balance_set(desc))
 841		irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
 842	if (irq_settings_is_per_cpu(desc))
 843		irqd_set(&desc->irq_data, IRQD_PER_CPU);
 844	if (irq_settings_can_move_pcntxt(desc))
 845		irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT);
 846	if (irq_settings_is_level(desc))
 847		irqd_set(&desc->irq_data, IRQD_LEVEL);
 848
 849	irqd_set(&desc->irq_data, irq_settings_get_trigger_mask(desc));
 850
 851	irq_put_desc_unlock(desc, flags);
 852}
 853EXPORT_SYMBOL_GPL(irq_modify_status);
 854
 855/**
 856 *	irq_cpu_online - Invoke all irq_cpu_online functions.
 857 *
 858 *	Iterate through all irqs and invoke the chip.irq_cpu_online()
 859 *	for each.
 860 */
 861void irq_cpu_online(void)
 862{
 863	struct irq_desc *desc;
 864	struct irq_chip *chip;
 865	unsigned long flags;
 866	unsigned int irq;
 867
 868	for_each_active_irq(irq) {
 869		desc = irq_to_desc(irq);
 870		if (!desc)
 871			continue;
 872
 873		raw_spin_lock_irqsave(&desc->lock, flags);
 874
 875		chip = irq_data_get_irq_chip(&desc->irq_data);
 876		if (chip && chip->irq_cpu_online &&
 877		    (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
 878		     !irqd_irq_disabled(&desc->irq_data)))
 879			chip->irq_cpu_online(&desc->irq_data);
 880
 881		raw_spin_unlock_irqrestore(&desc->lock, flags);
 882	}
 883}
 884
 885/**
 886 *	irq_cpu_offline - Invoke all irq_cpu_offline functions.
 887 *
 888 *	Iterate through all irqs and invoke the chip.irq_cpu_offline()
 889 *	for each.
 890 */
 891void irq_cpu_offline(void)
 892{
 893	struct irq_desc *desc;
 894	struct irq_chip *chip;
 895	unsigned long flags;
 896	unsigned int irq;
 897
 898	for_each_active_irq(irq) {
 899		desc = irq_to_desc(irq);
 900		if (!desc)
 901			continue;
 902
 903		raw_spin_lock_irqsave(&desc->lock, flags);
 904
 905		chip = irq_data_get_irq_chip(&desc->irq_data);
 906		if (chip && chip->irq_cpu_offline &&
 907		    (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
 908		     !irqd_irq_disabled(&desc->irq_data)))
 909			chip->irq_cpu_offline(&desc->irq_data);
 910
 911		raw_spin_unlock_irqrestore(&desc->lock, flags);
 912	}
 913}
 914
 915#ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
 916/**
 917 * irq_chip_enable_parent - Enable the parent interrupt (defaults to unmask if
 918 * NULL)
 919 * @data:	Pointer to interrupt specific data
 920 */
 921void irq_chip_enable_parent(struct irq_data *data)
 922{
 923	data = data->parent_data;
 924	if (data->chip->irq_enable)
 925		data->chip->irq_enable(data);
 926	else
 927		data->chip->irq_unmask(data);
 928}
 929
 930/**
 931 * irq_chip_disable_parent - Disable the parent interrupt (defaults to mask if
 932 * NULL)
 933 * @data:	Pointer to interrupt specific data
 934 */
 935void irq_chip_disable_parent(struct irq_data *data)
 936{
 937	data = data->parent_data;
 938	if (data->chip->irq_disable)
 939		data->chip->irq_disable(data);
 940	else
 941		data->chip->irq_mask(data);
 942}
 943
 944/**
 945 * irq_chip_ack_parent - Acknowledge the parent interrupt
 946 * @data:	Pointer to interrupt specific data
 947 */
 948void irq_chip_ack_parent(struct irq_data *data)
 949{
 950	data = data->parent_data;
 951	data->chip->irq_ack(data);
 952}
 953EXPORT_SYMBOL_GPL(irq_chip_ack_parent);
 954
 955/**
 956 * irq_chip_mask_parent - Mask the parent interrupt
 957 * @data:	Pointer to interrupt specific data
 958 */
 959void irq_chip_mask_parent(struct irq_data *data)
 960{
 961	data = data->parent_data;
 962	data->chip->irq_mask(data);
 963}
 964EXPORT_SYMBOL_GPL(irq_chip_mask_parent);
 965
 966/**
 967 * irq_chip_unmask_parent - Unmask the parent interrupt
 968 * @data:	Pointer to interrupt specific data
 969 */
 970void irq_chip_unmask_parent(struct irq_data *data)
 971{
 972	data = data->parent_data;
 973	data->chip->irq_unmask(data);
 974}
 975EXPORT_SYMBOL_GPL(irq_chip_unmask_parent);
 976
 977/**
 978 * irq_chip_eoi_parent - Invoke EOI on the parent interrupt
 979 * @data:	Pointer to interrupt specific data
 980 */
 981void irq_chip_eoi_parent(struct irq_data *data)
 982{
 983	data = data->parent_data;
 984	data->chip->irq_eoi(data);
 985}
 986EXPORT_SYMBOL_GPL(irq_chip_eoi_parent);
 987
 988/**
 989 * irq_chip_set_affinity_parent - Set affinity on the parent interrupt
 990 * @data:	Pointer to interrupt specific data
 991 * @dest:	The affinity mask to set
 992 * @force:	Flag to enforce setting (disable online checks)
 993 *
 994 * Conditinal, as the underlying parent chip might not implement it.
 995 */
 996int irq_chip_set_affinity_parent(struct irq_data *data,
 997				 const struct cpumask *dest, bool force)
 998{
 999	data = data->parent_data;
1000	if (data->chip->irq_set_affinity)
1001		return data->chip->irq_set_affinity(data, dest, force);
1002
1003	return -ENOSYS;
1004}
1005
1006/**
1007 * irq_chip_set_type_parent - Set IRQ type on the parent interrupt
1008 * @data:	Pointer to interrupt specific data
1009 * @type:	IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
1010 *
1011 * Conditional, as the underlying parent chip might not implement it.
1012 */
1013int irq_chip_set_type_parent(struct irq_data *data, unsigned int type)
1014{
1015	data = data->parent_data;
1016
1017	if (data->chip->irq_set_type)
1018		return data->chip->irq_set_type(data, type);
1019
1020	return -ENOSYS;
1021}
1022EXPORT_SYMBOL_GPL(irq_chip_set_type_parent);
1023
1024/**
1025 * irq_chip_retrigger_hierarchy - Retrigger an interrupt in hardware
1026 * @data:	Pointer to interrupt specific data
1027 *
1028 * Iterate through the domain hierarchy of the interrupt and check
1029 * whether a hw retrigger function exists. If yes, invoke it.
1030 */
1031int irq_chip_retrigger_hierarchy(struct irq_data *data)
1032{
1033	for (data = data->parent_data; data; data = data->parent_data)
1034		if (data->chip && data->chip->irq_retrigger)
1035			return data->chip->irq_retrigger(data);
1036
1037	return 0;
1038}
1039
1040/**
1041 * irq_chip_set_vcpu_affinity_parent - Set vcpu affinity on the parent interrupt
1042 * @data:	Pointer to interrupt specific data
1043 * @vcpu_info:	The vcpu affinity information
1044 */
1045int irq_chip_set_vcpu_affinity_parent(struct irq_data *data, void *vcpu_info)
1046{
1047	data = data->parent_data;
1048	if (data->chip->irq_set_vcpu_affinity)
1049		return data->chip->irq_set_vcpu_affinity(data, vcpu_info);
1050
1051	return -ENOSYS;
1052}
1053
1054/**
1055 * irq_chip_set_wake_parent - Set/reset wake-up on the parent interrupt
1056 * @data:	Pointer to interrupt specific data
1057 * @on:		Whether to set or reset the wake-up capability of this irq
1058 *
1059 * Conditional, as the underlying parent chip might not implement it.
1060 */
1061int irq_chip_set_wake_parent(struct irq_data *data, unsigned int on)
1062{
1063	data = data->parent_data;
1064	if (data->chip->irq_set_wake)
1065		return data->chip->irq_set_wake(data, on);
1066
1067	return -ENOSYS;
1068}
1069#endif
1070
1071/**
1072 * irq_chip_compose_msi_msg - Componse msi message for a irq chip
1073 * @data:	Pointer to interrupt specific data
1074 * @msg:	Pointer to the MSI message
1075 *
1076 * For hierarchical domains we find the first chip in the hierarchy
1077 * which implements the irq_compose_msi_msg callback. For non
1078 * hierarchical we use the top level chip.
1079 */
1080int irq_chip_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
1081{
1082	struct irq_data *pos = NULL;
1083
1084#ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
1085	for (; data; data = data->parent_data)
1086#endif
1087		if (data->chip && data->chip->irq_compose_msi_msg)
1088			pos = data;
1089	if (!pos)
1090		return -ENOSYS;
1091
1092	pos->chip->irq_compose_msi_msg(pos, msg);
1093
1094	return 0;
1095}
v3.1
  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
 19#include "internals.h"
 20
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 21/**
 22 *	irq_set_chip - set the irq chip for an irq
 23 *	@irq:	irq number
 24 *	@chip:	pointer to irq chip description structure
 25 */
 26int irq_set_chip(unsigned int irq, struct irq_chip *chip)
 27{
 28	unsigned long flags;
 29	struct irq_desc *desc = irq_get_desc_lock(irq, &flags);
 30
 31	if (!desc)
 32		return -EINVAL;
 33
 34	if (!chip)
 35		chip = &no_irq_chip;
 36
 37	desc->irq_data.chip = chip;
 38	irq_put_desc_unlock(desc, flags);
 39	/*
 40	 * For !CONFIG_SPARSE_IRQ make the irq show up in
 41	 * allocated_irqs. For the CONFIG_SPARSE_IRQ case, it is
 42	 * already marked, and this call is harmless.
 43	 */
 44	irq_reserve_irq(irq);
 45	return 0;
 46}
 47EXPORT_SYMBOL(irq_set_chip);
 48
 49/**
 50 *	irq_set_type - set the irq trigger type for an irq
 51 *	@irq:	irq number
 52 *	@type:	IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
 53 */
 54int irq_set_irq_type(unsigned int irq, unsigned int type)
 55{
 56	unsigned long flags;
 57	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags);
 58	int ret = 0;
 59
 60	if (!desc)
 61		return -EINVAL;
 62
 63	type &= IRQ_TYPE_SENSE_MASK;
 64	if (type != IRQ_TYPE_NONE)
 65		ret = __irq_set_trigger(desc, irq, type);
 66	irq_put_desc_busunlock(desc, flags);
 67	return ret;
 68}
 69EXPORT_SYMBOL(irq_set_irq_type);
 70
 71/**
 72 *	irq_set_handler_data - set irq handler data for an irq
 73 *	@irq:	Interrupt number
 74 *	@data:	Pointer to interrupt specific data
 75 *
 76 *	Set the hardware irq controller data for an irq
 77 */
 78int irq_set_handler_data(unsigned int irq, void *data)
 79{
 80	unsigned long flags;
 81	struct irq_desc *desc = irq_get_desc_lock(irq, &flags);
 82
 83	if (!desc)
 84		return -EINVAL;
 85	desc->irq_data.handler_data = data;
 86	irq_put_desc_unlock(desc, flags);
 87	return 0;
 88}
 89EXPORT_SYMBOL(irq_set_handler_data);
 90
 91/**
 92 *	irq_set_msi_desc - set MSI descriptor data for an irq
 93 *	@irq:	Interrupt number
 94 *	@entry:	Pointer to MSI descriptor data
 
 95 *
 96 *	Set the MSI descriptor entry for an irq
 97 */
 98int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry)
 
 99{
100	unsigned long flags;
101	struct irq_desc *desc = irq_get_desc_lock(irq, &flags);
102
103	if (!desc)
104		return -EINVAL;
105	desc->irq_data.msi_desc = entry;
106	if (entry)
107		entry->irq = irq;
108	irq_put_desc_unlock(desc, flags);
109	return 0;
110}
111
112/**
 
 
 
 
 
 
 
 
 
 
 
 
113 *	irq_set_chip_data - set irq chip data for an irq
114 *	@irq:	Interrupt number
115 *	@data:	Pointer to chip specific data
116 *
117 *	Set the hardware irq chip data for an irq
118 */
119int irq_set_chip_data(unsigned int irq, void *data)
120{
121	unsigned long flags;
122	struct irq_desc *desc = irq_get_desc_lock(irq, &flags);
123
124	if (!desc)
125		return -EINVAL;
126	desc->irq_data.chip_data = data;
127	irq_put_desc_unlock(desc, flags);
128	return 0;
129}
130EXPORT_SYMBOL(irq_set_chip_data);
131
132struct irq_data *irq_get_irq_data(unsigned int irq)
133{
134	struct irq_desc *desc = irq_to_desc(irq);
135
136	return desc ? &desc->irq_data : NULL;
137}
138EXPORT_SYMBOL_GPL(irq_get_irq_data);
139
140static void irq_state_clr_disabled(struct irq_desc *desc)
141{
142	irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED);
143}
144
145static void irq_state_set_disabled(struct irq_desc *desc)
146{
147	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
148}
149
150static void irq_state_clr_masked(struct irq_desc *desc)
151{
152	irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED);
153}
154
155static void irq_state_set_masked(struct irq_desc *desc)
156{
157	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
158}
159
160int irq_startup(struct irq_desc *desc)
161{
 
 
162	irq_state_clr_disabled(desc);
163	desc->depth = 0;
164
 
165	if (desc->irq_data.chip->irq_startup) {
166		int ret = desc->irq_data.chip->irq_startup(&desc->irq_data);
167		irq_state_clr_masked(desc);
168		return ret;
 
169	}
170
171	irq_enable(desc);
172	return 0;
173}
174
175void irq_shutdown(struct irq_desc *desc)
176{
177	irq_state_set_disabled(desc);
178	desc->depth = 1;
179	if (desc->irq_data.chip->irq_shutdown)
180		desc->irq_data.chip->irq_shutdown(&desc->irq_data);
181	else if (desc->irq_data.chip->irq_disable)
182		desc->irq_data.chip->irq_disable(&desc->irq_data);
183	else
184		desc->irq_data.chip->irq_mask(&desc->irq_data);
 
185	irq_state_set_masked(desc);
186}
187
188void irq_enable(struct irq_desc *desc)
189{
190	irq_state_clr_disabled(desc);
191	if (desc->irq_data.chip->irq_enable)
192		desc->irq_data.chip->irq_enable(&desc->irq_data);
193	else
194		desc->irq_data.chip->irq_unmask(&desc->irq_data);
195	irq_state_clr_masked(desc);
196}
197
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
198void irq_disable(struct irq_desc *desc)
199{
200	irq_state_set_disabled(desc);
201	if (desc->irq_data.chip->irq_disable) {
202		desc->irq_data.chip->irq_disable(&desc->irq_data);
203		irq_state_set_masked(desc);
 
 
204	}
205}
206
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
207static inline void mask_ack_irq(struct irq_desc *desc)
208{
209	if (desc->irq_data.chip->irq_mask_ack)
210		desc->irq_data.chip->irq_mask_ack(&desc->irq_data);
211	else {
212		desc->irq_data.chip->irq_mask(&desc->irq_data);
213		if (desc->irq_data.chip->irq_ack)
214			desc->irq_data.chip->irq_ack(&desc->irq_data);
215	}
216	irq_state_set_masked(desc);
217}
218
219void mask_irq(struct irq_desc *desc)
220{
221	if (desc->irq_data.chip->irq_mask) {
222		desc->irq_data.chip->irq_mask(&desc->irq_data);
223		irq_state_set_masked(desc);
224	}
225}
226
227void unmask_irq(struct irq_desc *desc)
228{
229	if (desc->irq_data.chip->irq_unmask) {
230		desc->irq_data.chip->irq_unmask(&desc->irq_data);
231		irq_state_clr_masked(desc);
232	}
233}
234
 
 
 
 
 
 
 
 
 
 
 
 
 
235/*
236 *	handle_nested_irq - Handle a nested irq from a irq thread
237 *	@irq:	the interrupt number
238 *
239 *	Handle interrupts which are nested into a threaded interrupt
240 *	handler. The handler function is called inside the calling
241 *	threads context.
242 */
243void handle_nested_irq(unsigned int irq)
244{
245	struct irq_desc *desc = irq_to_desc(irq);
246	struct irqaction *action;
247	irqreturn_t action_ret;
248
249	might_sleep();
250
251	raw_spin_lock_irq(&desc->lock);
252
253	kstat_incr_irqs_this_cpu(irq, desc);
254
255	action = desc->action;
256	if (unlikely(!action || irqd_irq_disabled(&desc->irq_data)))
 
257		goto out_unlock;
 
258
 
259	irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
260	raw_spin_unlock_irq(&desc->lock);
261
262	action_ret = action->thread_fn(action->irq, action->dev_id);
263	if (!noirqdebug)
264		note_interrupt(irq, desc, action_ret);
265
266	raw_spin_lock_irq(&desc->lock);
267	irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
268
269out_unlock:
270	raw_spin_unlock_irq(&desc->lock);
271}
272EXPORT_SYMBOL_GPL(handle_nested_irq);
273
274static bool irq_check_poll(struct irq_desc *desc)
275{
276	if (!(desc->istate & IRQS_POLL_INPROGRESS))
277		return false;
278	return irq_wait_for_poll(desc);
279}
280
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
281/**
282 *	handle_simple_irq - Simple and software-decoded IRQs.
283 *	@irq:	the interrupt number
284 *	@desc:	the interrupt description structure for this irq
285 *
286 *	Simple interrupts are either sent from a demultiplexing interrupt
287 *	handler or come from hardware, where no interrupt hardware control
288 *	is necessary.
289 *
290 *	Note: The caller is expected to handle the ack, clear, mask and
291 *	unmask issues if necessary.
292 */
293void
294handle_simple_irq(unsigned int irq, struct irq_desc *desc)
295{
296	raw_spin_lock(&desc->lock);
297
298	if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
299		if (!irq_check_poll(desc))
300			goto out_unlock;
301
302	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
303	kstat_incr_irqs_this_cpu(irq, desc);
304
305	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data)))
 
306		goto out_unlock;
 
307
 
308	handle_irq_event(desc);
309
310out_unlock:
311	raw_spin_unlock(&desc->lock);
312}
313EXPORT_SYMBOL_GPL(handle_simple_irq);
314
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
315/**
316 *	handle_level_irq - Level type irq handler
317 *	@irq:	the interrupt number
318 *	@desc:	the interrupt description structure for this irq
319 *
320 *	Level type interrupts are active as long as the hardware line has
321 *	the active level. This may require to mask the interrupt and unmask
322 *	it after the associated handler has acknowledged the device, so the
323 *	interrupt line is back to inactive.
324 */
325void
326handle_level_irq(unsigned int irq, struct irq_desc *desc)
327{
328	raw_spin_lock(&desc->lock);
329	mask_ack_irq(desc);
330
331	if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
332		if (!irq_check_poll(desc))
333			goto out_unlock;
334
335	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
336	kstat_incr_irqs_this_cpu(irq, desc);
337
338	/*
339	 * If its disabled or no action available
340	 * keep it masked and get out of here
341	 */
342	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data)))
 
343		goto out_unlock;
 
344
 
345	handle_irq_event(desc);
346
347	if (!irqd_irq_disabled(&desc->irq_data) && !(desc->istate & IRQS_ONESHOT))
348		unmask_irq(desc);
349out_unlock:
350	raw_spin_unlock(&desc->lock);
351}
352EXPORT_SYMBOL_GPL(handle_level_irq);
353
354#ifdef CONFIG_IRQ_PREFLOW_FASTEOI
355static inline void preflow_handler(struct irq_desc *desc)
356{
357	if (desc->preflow_handler)
358		desc->preflow_handler(&desc->irq_data);
359}
360#else
361static inline void preflow_handler(struct irq_desc *desc) { }
362#endif
363
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
364/**
365 *	handle_fasteoi_irq - irq handler for transparent controllers
366 *	@irq:	the interrupt number
367 *	@desc:	the interrupt description structure for this irq
368 *
369 *	Only a single callback will be issued to the chip: an ->eoi()
370 *	call when the interrupt has been serviced. This enables support
371 *	for modern forms of interrupt handlers, which handle the flow
372 *	details in hardware, transparently.
373 */
374void
375handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
376{
 
 
377	raw_spin_lock(&desc->lock);
378
379	if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
380		if (!irq_check_poll(desc))
381			goto out;
382
383	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
384	kstat_incr_irqs_this_cpu(irq, desc);
385
386	/*
387	 * If its disabled or no action available
388	 * then mask it and get out of here:
389	 */
390	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
391		desc->istate |= IRQS_PENDING;
392		mask_irq(desc);
393		goto out;
394	}
395
 
396	if (desc->istate & IRQS_ONESHOT)
397		mask_irq(desc);
398
399	preflow_handler(desc);
400	handle_irq_event(desc);
401
402out_eoi:
403	desc->irq_data.chip->irq_eoi(&desc->irq_data);
404out_unlock:
405	raw_spin_unlock(&desc->lock);
406	return;
407out:
408	if (!(desc->irq_data.chip->flags & IRQCHIP_EOI_IF_HANDLED))
409		goto out_eoi;
410	goto out_unlock;
411}
 
412
413/**
414 *	handle_edge_irq - edge type IRQ handler
415 *	@irq:	the interrupt number
416 *	@desc:	the interrupt description structure for this irq
417 *
418 *	Interrupt occures on the falling and/or rising edge of a hardware
419 *	signal. The occurrence is latched into the irq controller hardware
420 *	and must be acked in order to be reenabled. After the ack another
421 *	interrupt can happen on the same source even before the first one
422 *	is handled by the associated event handler. If this happens it
423 *	might be necessary to disable (mask) the interrupt depending on the
424 *	controller hardware. This requires to reenable the interrupt inside
425 *	of the loop which handles the interrupts which have arrived while
426 *	the handler was running. If all pending interrupts are handled, the
427 *	loop is left.
428 */
429void
430handle_edge_irq(unsigned int irq, struct irq_desc *desc)
431{
432	raw_spin_lock(&desc->lock);
433
434	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 
 
 
 
 
 
 
435	/*
436	 * If we're currently running this IRQ, or its disabled,
437	 * we shouldn't process the IRQ. Mark it pending, handle
438	 * the necessary masking and go out
439	 */
440	if (unlikely(irqd_irq_disabled(&desc->irq_data) ||
441		     irqd_irq_inprogress(&desc->irq_data) || !desc->action)) {
442		if (!irq_check_poll(desc)) {
443			desc->istate |= IRQS_PENDING;
444			mask_ack_irq(desc);
445			goto out_unlock;
446		}
447	}
448	kstat_incr_irqs_this_cpu(irq, desc);
 
449
450	/* Start handling the irq */
451	desc->irq_data.chip->irq_ack(&desc->irq_data);
452
453	do {
454		if (unlikely(!desc->action)) {
455			mask_irq(desc);
456			goto out_unlock;
457		}
458
459		/*
460		 * When another irq arrived while we were handling
461		 * one, we could have masked the irq.
462		 * Renable it, if it was not disabled in meantime.
463		 */
464		if (unlikely(desc->istate & IRQS_PENDING)) {
465			if (!irqd_irq_disabled(&desc->irq_data) &&
466			    irqd_irq_masked(&desc->irq_data))
467				unmask_irq(desc);
468		}
469
470		handle_irq_event(desc);
471
472	} while ((desc->istate & IRQS_PENDING) &&
473		 !irqd_irq_disabled(&desc->irq_data));
474
475out_unlock:
476	raw_spin_unlock(&desc->lock);
477}
 
478
479#ifdef CONFIG_IRQ_EDGE_EOI_HANDLER
480/**
481 *	handle_edge_eoi_irq - edge eoi type IRQ handler
482 *	@irq:	the interrupt number
483 *	@desc:	the interrupt description structure for this irq
484 *
485 * Similar as the above handle_edge_irq, but using eoi and w/o the
486 * mask/unmask logic.
487 */
488void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc)
489{
490	struct irq_chip *chip = irq_desc_get_chip(desc);
491
492	raw_spin_lock(&desc->lock);
493
494	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 
 
 
 
 
 
495	/*
496	 * If we're currently running this IRQ, or its disabled,
497	 * we shouldn't process the IRQ. Mark it pending, handle
498	 * the necessary masking and go out
499	 */
500	if (unlikely(irqd_irq_disabled(&desc->irq_data) ||
501		     irqd_irq_inprogress(&desc->irq_data) || !desc->action)) {
502		if (!irq_check_poll(desc)) {
503			desc->istate |= IRQS_PENDING;
504			goto out_eoi;
505		}
506	}
507	kstat_incr_irqs_this_cpu(irq, desc);
 
508
509	do {
510		if (unlikely(!desc->action))
511			goto out_eoi;
512
513		handle_irq_event(desc);
514
515	} while ((desc->istate & IRQS_PENDING) &&
516		 !irqd_irq_disabled(&desc->irq_data));
517
518out_eoi:
519	chip->irq_eoi(&desc->irq_data);
520	raw_spin_unlock(&desc->lock);
521}
522#endif
523
524/**
525 *	handle_percpu_irq - Per CPU local irq handler
526 *	@irq:	the interrupt number
527 *	@desc:	the interrupt description structure for this irq
528 *
529 *	Per CPU interrupts on SMP machines without locking requirements
530 */
531void
532handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
533{
534	struct irq_chip *chip = irq_desc_get_chip(desc);
535
536	kstat_incr_irqs_this_cpu(irq, desc);
537
538	if (chip->irq_ack)
539		chip->irq_ack(&desc->irq_data);
540
541	handle_irq_event_percpu(desc, desc->action);
542
543	if (chip->irq_eoi)
544		chip->irq_eoi(&desc->irq_data);
545}
546
547void
548__irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
549		  const char *name)
 
 
 
 
 
 
 
 
 
550{
551	unsigned long flags;
552	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags);
 
 
 
 
 
 
 
 
 
 
 
 
553
554	if (!desc)
555		return;
 
556
 
 
 
 
557	if (!handle) {
558		handle = handle_bad_irq;
559	} else {
560		if (WARN_ON(desc->irq_data.chip == &no_irq_chip))
561			goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
562	}
563
564	/* Uninstall? */
565	if (handle == handle_bad_irq) {
566		if (desc->irq_data.chip != &no_irq_chip)
567			mask_ack_irq(desc);
568		irq_state_set_disabled(desc);
 
 
569		desc->depth = 1;
570	}
571	desc->handle_irq = handle;
572	desc->name = name;
573
574	if (handle != handle_bad_irq && is_chained) {
575		irq_settings_set_noprobe(desc);
576		irq_settings_set_norequest(desc);
577		irq_settings_set_nothread(desc);
578		irq_startup(desc);
 
579	}
580out:
 
 
 
 
 
 
 
 
 
 
 
 
581	irq_put_desc_busunlock(desc, flags);
582}
583EXPORT_SYMBOL_GPL(__irq_set_handler);
584
585void
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
586irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
587			      irq_flow_handler_t handle, const char *name)
588{
589	irq_set_chip(irq, chip);
590	__irq_set_handler(irq, handle, 0, name);
591}
 
592
593void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
594{
595	unsigned long flags;
596	struct irq_desc *desc = irq_get_desc_lock(irq, &flags);
597
598	if (!desc)
599		return;
600	irq_settings_clr_and_set(desc, clr, set);
601
602	irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU |
603		   IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT);
604	if (irq_settings_has_no_balance_set(desc))
605		irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
606	if (irq_settings_is_per_cpu(desc))
607		irqd_set(&desc->irq_data, IRQD_PER_CPU);
608	if (irq_settings_can_move_pcntxt(desc))
609		irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT);
610	if (irq_settings_is_level(desc))
611		irqd_set(&desc->irq_data, IRQD_LEVEL);
612
613	irqd_set(&desc->irq_data, irq_settings_get_trigger_mask(desc));
614
615	irq_put_desc_unlock(desc, flags);
616}
617EXPORT_SYMBOL_GPL(irq_modify_status);
618
619/**
620 *	irq_cpu_online - Invoke all irq_cpu_online functions.
621 *
622 *	Iterate through all irqs and invoke the chip.irq_cpu_online()
623 *	for each.
624 */
625void irq_cpu_online(void)
626{
627	struct irq_desc *desc;
628	struct irq_chip *chip;
629	unsigned long flags;
630	unsigned int irq;
631
632	for_each_active_irq(irq) {
633		desc = irq_to_desc(irq);
634		if (!desc)
635			continue;
636
637		raw_spin_lock_irqsave(&desc->lock, flags);
638
639		chip = irq_data_get_irq_chip(&desc->irq_data);
640		if (chip && chip->irq_cpu_online &&
641		    (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
642		     !irqd_irq_disabled(&desc->irq_data)))
643			chip->irq_cpu_online(&desc->irq_data);
644
645		raw_spin_unlock_irqrestore(&desc->lock, flags);
646	}
647}
648
649/**
650 *	irq_cpu_offline - Invoke all irq_cpu_offline functions.
651 *
652 *	Iterate through all irqs and invoke the chip.irq_cpu_offline()
653 *	for each.
654 */
655void irq_cpu_offline(void)
656{
657	struct irq_desc *desc;
658	struct irq_chip *chip;
659	unsigned long flags;
660	unsigned int irq;
661
662	for_each_active_irq(irq) {
663		desc = irq_to_desc(irq);
664		if (!desc)
665			continue;
666
667		raw_spin_lock_irqsave(&desc->lock, flags);
668
669		chip = irq_data_get_irq_chip(&desc->irq_data);
670		if (chip && chip->irq_cpu_offline &&
671		    (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
672		     !irqd_irq_disabled(&desc->irq_data)))
673			chip->irq_cpu_offline(&desc->irq_data);
674
675		raw_spin_unlock_irqrestore(&desc->lock, flags);
676	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
677}