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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}
v3.5.6
  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
 19#include <trace/events/irq.h>
 20
 21#include "internals.h"
 22
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 23/**
 24 *	irq_set_chip - set the irq chip for an irq
 25 *	@irq:	irq number
 26 *	@chip:	pointer to irq chip description structure
 27 */
 28int irq_set_chip(unsigned int irq, struct irq_chip *chip)
 29{
 30	unsigned long flags;
 31	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
 32
 33	if (!desc)
 34		return -EINVAL;
 35
 36	if (!chip)
 37		chip = &no_irq_chip;
 38
 39	desc->irq_data.chip = chip;
 40	irq_put_desc_unlock(desc, flags);
 41	/*
 42	 * For !CONFIG_SPARSE_IRQ make the irq show up in
 43	 * allocated_irqs. For the CONFIG_SPARSE_IRQ case, it is
 44	 * already marked, and this call is harmless.
 45	 */
 46	irq_reserve_irq(irq);
 47	return 0;
 48}
 49EXPORT_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 */
 56int 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, irq, type);
 67	irq_put_desc_busunlock(desc, flags);
 68	return ret;
 69}
 70EXPORT_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 */
 79int 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_data.handler_data = data;
 87	irq_put_desc_unlock(desc, flags);
 88	return 0;
 89}
 90EXPORT_SYMBOL(irq_set_handler_data);
 91
 92/**
 93 *	irq_set_msi_desc - set MSI descriptor data for an irq
 94 *	@irq:	Interrupt number
 95 *	@entry:	Pointer to MSI descriptor data
 
 96 *
 97 *	Set the MSI descriptor entry for an irq
 98 */
 99int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry)
 
100{
101	unsigned long flags;
102	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
103
104	if (!desc)
105		return -EINVAL;
106	desc->irq_data.msi_desc = entry;
107	if (entry)
108		entry->irq = irq;
109	irq_put_desc_unlock(desc, flags);
110	return 0;
111}
112
113/**
 
 
 
 
 
 
 
 
 
 
 
 
114 *	irq_set_chip_data - set irq chip data for an irq
115 *	@irq:	Interrupt number
116 *	@data:	Pointer to chip specific data
117 *
118 *	Set the hardware irq chip data for an irq
119 */
120int irq_set_chip_data(unsigned int irq, void *data)
121{
122	unsigned long flags;
123	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
124
125	if (!desc)
126		return -EINVAL;
127	desc->irq_data.chip_data = data;
128	irq_put_desc_unlock(desc, flags);
129	return 0;
130}
131EXPORT_SYMBOL(irq_set_chip_data);
132
133struct irq_data *irq_get_irq_data(unsigned int irq)
134{
135	struct irq_desc *desc = irq_to_desc(irq);
136
137	return desc ? &desc->irq_data : NULL;
138}
139EXPORT_SYMBOL_GPL(irq_get_irq_data);
140
141static void irq_state_clr_disabled(struct irq_desc *desc)
142{
143	irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED);
144}
145
146static void irq_state_set_disabled(struct irq_desc *desc)
147{
148	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
149}
150
151static void irq_state_clr_masked(struct irq_desc *desc)
152{
153	irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED);
154}
155
156static void irq_state_set_masked(struct irq_desc *desc)
157{
158	irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
159}
160
161int irq_startup(struct irq_desc *desc, bool resend)
162{
163	int ret = 0;
164
165	irq_state_clr_disabled(desc);
166	desc->depth = 0;
167
 
168	if (desc->irq_data.chip->irq_startup) {
169		ret = desc->irq_data.chip->irq_startup(&desc->irq_data);
170		irq_state_clr_masked(desc);
171	} else {
172		irq_enable(desc);
173	}
174	if (resend)
175		check_irq_resend(desc, desc->irq_data.irq);
176	return ret;
177}
178
179void irq_shutdown(struct irq_desc *desc)
180{
181	irq_state_set_disabled(desc);
182	desc->depth = 1;
183	if (desc->irq_data.chip->irq_shutdown)
184		desc->irq_data.chip->irq_shutdown(&desc->irq_data);
185	else if (desc->irq_data.chip->irq_disable)
186		desc->irq_data.chip->irq_disable(&desc->irq_data);
187	else
188		desc->irq_data.chip->irq_mask(&desc->irq_data);
 
189	irq_state_set_masked(desc);
190}
191
192void irq_enable(struct irq_desc *desc)
193{
194	irq_state_clr_disabled(desc);
195	if (desc->irq_data.chip->irq_enable)
196		desc->irq_data.chip->irq_enable(&desc->irq_data);
197	else
198		desc->irq_data.chip->irq_unmask(&desc->irq_data);
199	irq_state_clr_masked(desc);
200}
201
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
202void irq_disable(struct irq_desc *desc)
203{
204	irq_state_set_disabled(desc);
205	if (desc->irq_data.chip->irq_disable) {
206		desc->irq_data.chip->irq_disable(&desc->irq_data);
207		irq_state_set_masked(desc);
 
 
208	}
209}
210
211void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu)
212{
213	if (desc->irq_data.chip->irq_enable)
214		desc->irq_data.chip->irq_enable(&desc->irq_data);
215	else
216		desc->irq_data.chip->irq_unmask(&desc->irq_data);
217	cpumask_set_cpu(cpu, desc->percpu_enabled);
218}
219
220void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu)
221{
222	if (desc->irq_data.chip->irq_disable)
223		desc->irq_data.chip->irq_disable(&desc->irq_data);
224	else
225		desc->irq_data.chip->irq_mask(&desc->irq_data);
226	cpumask_clear_cpu(cpu, desc->percpu_enabled);
227}
228
229static inline void mask_ack_irq(struct irq_desc *desc)
230{
231	if (desc->irq_data.chip->irq_mask_ack)
232		desc->irq_data.chip->irq_mask_ack(&desc->irq_data);
233	else {
234		desc->irq_data.chip->irq_mask(&desc->irq_data);
235		if (desc->irq_data.chip->irq_ack)
236			desc->irq_data.chip->irq_ack(&desc->irq_data);
237	}
238	irq_state_set_masked(desc);
239}
240
241void mask_irq(struct irq_desc *desc)
242{
243	if (desc->irq_data.chip->irq_mask) {
244		desc->irq_data.chip->irq_mask(&desc->irq_data);
245		irq_state_set_masked(desc);
246	}
247}
248
249void unmask_irq(struct irq_desc *desc)
250{
251	if (desc->irq_data.chip->irq_unmask) {
252		desc->irq_data.chip->irq_unmask(&desc->irq_data);
253		irq_state_clr_masked(desc);
254	}
255}
256
 
 
 
 
 
 
 
 
 
 
 
 
 
257/*
258 *	handle_nested_irq - Handle a nested irq from a irq thread
259 *	@irq:	the interrupt number
260 *
261 *	Handle interrupts which are nested into a threaded interrupt
262 *	handler. The handler function is called inside the calling
263 *	threads context.
264 */
265void handle_nested_irq(unsigned int irq)
266{
267	struct irq_desc *desc = irq_to_desc(irq);
268	struct irqaction *action;
269	irqreturn_t action_ret;
270
271	might_sleep();
272
273	raw_spin_lock_irq(&desc->lock);
274
275	kstat_incr_irqs_this_cpu(irq, desc);
276
277	action = desc->action;
278	if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) {
279		desc->istate |= IRQS_PENDING;
280		goto out_unlock;
281	}
282
 
283	irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
284	raw_spin_unlock_irq(&desc->lock);
285
286	action_ret = action->thread_fn(action->irq, action->dev_id);
287	if (!noirqdebug)
288		note_interrupt(irq, desc, action_ret);
289
290	raw_spin_lock_irq(&desc->lock);
291	irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
292
293out_unlock:
294	raw_spin_unlock_irq(&desc->lock);
295}
296EXPORT_SYMBOL_GPL(handle_nested_irq);
297
298static bool irq_check_poll(struct irq_desc *desc)
299{
300	if (!(desc->istate & IRQS_POLL_INPROGRESS))
301		return false;
302	return irq_wait_for_poll(desc);
303}
304
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
305/**
306 *	handle_simple_irq - Simple and software-decoded IRQs.
307 *	@irq:	the interrupt number
308 *	@desc:	the interrupt description structure for this irq
309 *
310 *	Simple interrupts are either sent from a demultiplexing interrupt
311 *	handler or come from hardware, where no interrupt hardware control
312 *	is necessary.
313 *
314 *	Note: The caller is expected to handle the ack, clear, mask and
315 *	unmask issues if necessary.
316 */
317void
318handle_simple_irq(unsigned int irq, struct irq_desc *desc)
319{
320	raw_spin_lock(&desc->lock);
321
322	if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
323		if (!irq_check_poll(desc))
324			goto out_unlock;
325
326	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
327	kstat_incr_irqs_this_cpu(irq, desc);
328
329	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
330		desc->istate |= IRQS_PENDING;
331		goto out_unlock;
332	}
333
 
334	handle_irq_event(desc);
335
336out_unlock:
337	raw_spin_unlock(&desc->lock);
338}
339EXPORT_SYMBOL_GPL(handle_simple_irq);
340
341/*
342 * Called unconditionally from handle_level_irq() and only for oneshot
343 * interrupts from handle_fasteoi_irq()
344 */
345static void cond_unmask_irq(struct irq_desc *desc)
346{
347	/*
348	 * We need to unmask in the following cases:
349	 * - Standard level irq (IRQF_ONESHOT is not set)
350	 * - Oneshot irq which did not wake the thread (caused by a
351	 *   spurious interrupt or a primary handler handling it
352	 *   completely).
353	 */
354	if (!irqd_irq_disabled(&desc->irq_data) &&
355	    irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot)
356		unmask_irq(desc);
357}
358
359/**
360 *	handle_level_irq - Level type irq handler
361 *	@irq:	the interrupt number
362 *	@desc:	the interrupt description structure for this irq
363 *
364 *	Level type interrupts are active as long as the hardware line has
365 *	the active level. This may require to mask the interrupt and unmask
366 *	it after the associated handler has acknowledged the device, so the
367 *	interrupt line is back to inactive.
368 */
369void
370handle_level_irq(unsigned int irq, struct irq_desc *desc)
371{
372	raw_spin_lock(&desc->lock);
373	mask_ack_irq(desc);
374
375	if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
376		if (!irq_check_poll(desc))
377			goto out_unlock;
378
379	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
380	kstat_incr_irqs_this_cpu(irq, desc);
381
382	/*
383	 * If its disabled or no action available
384	 * keep it masked and get out of here
385	 */
386	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
387		desc->istate |= IRQS_PENDING;
388		goto out_unlock;
389	}
390
 
391	handle_irq_event(desc);
392
393	cond_unmask_irq(desc);
394
395out_unlock:
396	raw_spin_unlock(&desc->lock);
397}
398EXPORT_SYMBOL_GPL(handle_level_irq);
399
400#ifdef CONFIG_IRQ_PREFLOW_FASTEOI
401static inline void preflow_handler(struct irq_desc *desc)
402{
403	if (desc->preflow_handler)
404		desc->preflow_handler(&desc->irq_data);
405}
406#else
407static inline void preflow_handler(struct irq_desc *desc) { }
408#endif
409
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
410/**
411 *	handle_fasteoi_irq - irq handler for transparent controllers
412 *	@irq:	the interrupt number
413 *	@desc:	the interrupt description structure for this irq
414 *
415 *	Only a single callback will be issued to the chip: an ->eoi()
416 *	call when the interrupt has been serviced. This enables support
417 *	for modern forms of interrupt handlers, which handle the flow
418 *	details in hardware, transparently.
419 */
420void
421handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
422{
 
 
423	raw_spin_lock(&desc->lock);
424
425	if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
426		if (!irq_check_poll(desc))
427			goto out;
428
429	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
430	kstat_incr_irqs_this_cpu(irq, desc);
431
432	/*
433	 * If its disabled or no action available
434	 * then mask it and get out of here:
435	 */
436	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
437		desc->istate |= IRQS_PENDING;
438		mask_irq(desc);
439		goto out;
440	}
441
 
442	if (desc->istate & IRQS_ONESHOT)
443		mask_irq(desc);
444
445	preflow_handler(desc);
446	handle_irq_event(desc);
447
448	if (desc->istate & IRQS_ONESHOT)
449		cond_unmask_irq(desc);
450
451out_eoi:
452	desc->irq_data.chip->irq_eoi(&desc->irq_data);
453out_unlock:
454	raw_spin_unlock(&desc->lock);
455	return;
456out:
457	if (!(desc->irq_data.chip->flags & IRQCHIP_EOI_IF_HANDLED))
458		goto out_eoi;
459	goto out_unlock;
460}
 
461
462/**
463 *	handle_edge_irq - edge type IRQ handler
464 *	@irq:	the interrupt number
465 *	@desc:	the interrupt description structure for this irq
466 *
467 *	Interrupt occures on the falling and/or rising edge of a hardware
468 *	signal. The occurrence is latched into the irq controller hardware
469 *	and must be acked in order to be reenabled. After the ack another
470 *	interrupt can happen on the same source even before the first one
471 *	is handled by the associated event handler. If this happens it
472 *	might be necessary to disable (mask) the interrupt depending on the
473 *	controller hardware. This requires to reenable the interrupt inside
474 *	of the loop which handles the interrupts which have arrived while
475 *	the handler was running. If all pending interrupts are handled, the
476 *	loop is left.
477 */
478void
479handle_edge_irq(unsigned int irq, struct irq_desc *desc)
480{
481	raw_spin_lock(&desc->lock);
482
483	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 
 
 
 
 
 
 
484	/*
485	 * If we're currently running this IRQ, or its disabled,
486	 * we shouldn't process the IRQ. Mark it pending, handle
487	 * the necessary masking and go out
488	 */
489	if (unlikely(irqd_irq_disabled(&desc->irq_data) ||
490		     irqd_irq_inprogress(&desc->irq_data) || !desc->action)) {
491		if (!irq_check_poll(desc)) {
492			desc->istate |= IRQS_PENDING;
493			mask_ack_irq(desc);
494			goto out_unlock;
495		}
496	}
497	kstat_incr_irqs_this_cpu(irq, desc);
 
498
499	/* Start handling the irq */
500	desc->irq_data.chip->irq_ack(&desc->irq_data);
501
502	do {
503		if (unlikely(!desc->action)) {
504			mask_irq(desc);
505			goto out_unlock;
506		}
507
508		/*
509		 * When another irq arrived while we were handling
510		 * one, we could have masked the irq.
511		 * Renable it, if it was not disabled in meantime.
512		 */
513		if (unlikely(desc->istate & IRQS_PENDING)) {
514			if (!irqd_irq_disabled(&desc->irq_data) &&
515			    irqd_irq_masked(&desc->irq_data))
516				unmask_irq(desc);
517		}
518
519		handle_irq_event(desc);
520
521	} while ((desc->istate & IRQS_PENDING) &&
522		 !irqd_irq_disabled(&desc->irq_data));
523
524out_unlock:
525	raw_spin_unlock(&desc->lock);
526}
527EXPORT_SYMBOL(handle_edge_irq);
528
529#ifdef CONFIG_IRQ_EDGE_EOI_HANDLER
530/**
531 *	handle_edge_eoi_irq - edge eoi type IRQ handler
532 *	@irq:	the interrupt number
533 *	@desc:	the interrupt description structure for this irq
534 *
535 * Similar as the above handle_edge_irq, but using eoi and w/o the
536 * mask/unmask logic.
537 */
538void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc)
539{
540	struct irq_chip *chip = irq_desc_get_chip(desc);
541
542	raw_spin_lock(&desc->lock);
543
544	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 
 
 
 
 
 
545	/*
546	 * If we're currently running this IRQ, or its disabled,
547	 * we shouldn't process the IRQ. Mark it pending, handle
548	 * the necessary masking and go out
549	 */
550	if (unlikely(irqd_irq_disabled(&desc->irq_data) ||
551		     irqd_irq_inprogress(&desc->irq_data) || !desc->action)) {
552		if (!irq_check_poll(desc)) {
553			desc->istate |= IRQS_PENDING;
554			goto out_eoi;
555		}
556	}
557	kstat_incr_irqs_this_cpu(irq, desc);
 
558
559	do {
560		if (unlikely(!desc->action))
561			goto out_eoi;
562
563		handle_irq_event(desc);
564
565	} while ((desc->istate & IRQS_PENDING) &&
566		 !irqd_irq_disabled(&desc->irq_data));
567
568out_eoi:
569	chip->irq_eoi(&desc->irq_data);
570	raw_spin_unlock(&desc->lock);
571}
572#endif
573
574/**
575 *	handle_percpu_irq - Per CPU local irq handler
576 *	@irq:	the interrupt number
577 *	@desc:	the interrupt description structure for this irq
578 *
579 *	Per CPU interrupts on SMP machines without locking requirements
580 */
581void
582handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
583{
584	struct irq_chip *chip = irq_desc_get_chip(desc);
585
586	kstat_incr_irqs_this_cpu(irq, desc);
587
588	if (chip->irq_ack)
589		chip->irq_ack(&desc->irq_data);
590
591	handle_irq_event_percpu(desc, desc->action);
592
593	if (chip->irq_eoi)
594		chip->irq_eoi(&desc->irq_data);
595}
596
597/**
598 * handle_percpu_devid_irq - Per CPU local irq handler with per cpu dev ids
599 * @irq:	the interrupt number
600 * @desc:	the interrupt description structure for this irq
601 *
602 * Per CPU interrupts on SMP machines without locking requirements. Same as
603 * handle_percpu_irq() above but with the following extras:
604 *
605 * action->percpu_dev_id is a pointer to percpu variables which
606 * contain the real device id for the cpu on which this handler is
607 * called
608 */
609void handle_percpu_devid_irq(unsigned int irq, struct irq_desc *desc)
610{
611	struct irq_chip *chip = irq_desc_get_chip(desc);
612	struct irqaction *action = desc->action;
613	void *dev_id = __this_cpu_ptr(action->percpu_dev_id);
 
614	irqreturn_t res;
615
616	kstat_incr_irqs_this_cpu(irq, desc);
617
618	if (chip->irq_ack)
619		chip->irq_ack(&desc->irq_data);
620
621	trace_irq_handler_entry(irq, action);
622	res = action->handler(irq, dev_id);
623	trace_irq_handler_exit(irq, action, res);
624
625	if (chip->irq_eoi)
626		chip->irq_eoi(&desc->irq_data);
627}
628
629void
630__irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
631		  const char *name)
632{
633	unsigned long flags;
634	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
635
636	if (!desc)
637		return;
638
639	if (!handle) {
640		handle = handle_bad_irq;
641	} else {
642		if (WARN_ON(desc->irq_data.chip == &no_irq_chip))
643			goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
644	}
645
646	/* Uninstall? */
647	if (handle == handle_bad_irq) {
648		if (desc->irq_data.chip != &no_irq_chip)
649			mask_ack_irq(desc);
650		irq_state_set_disabled(desc);
 
 
651		desc->depth = 1;
652	}
653	desc->handle_irq = handle;
654	desc->name = name;
655
656	if (handle != handle_bad_irq && is_chained) {
657		irq_settings_set_noprobe(desc);
658		irq_settings_set_norequest(desc);
659		irq_settings_set_nothread(desc);
 
660		irq_startup(desc, true);
661	}
662out:
 
 
 
 
 
 
 
 
 
 
 
 
663	irq_put_desc_busunlock(desc, flags);
664}
665EXPORT_SYMBOL_GPL(__irq_set_handler);
666
667void
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
668irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
669			      irq_flow_handler_t handle, const char *name)
670{
671	irq_set_chip(irq, chip);
672	__irq_set_handler(irq, handle, 0, name);
673}
 
674
675void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
676{
677	unsigned long flags;
678	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
679
680	if (!desc)
681		return;
682	irq_settings_clr_and_set(desc, clr, set);
683
684	irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU |
685		   IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT);
686	if (irq_settings_has_no_balance_set(desc))
687		irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
688	if (irq_settings_is_per_cpu(desc))
689		irqd_set(&desc->irq_data, IRQD_PER_CPU);
690	if (irq_settings_can_move_pcntxt(desc))
691		irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT);
692	if (irq_settings_is_level(desc))
693		irqd_set(&desc->irq_data, IRQD_LEVEL);
694
695	irqd_set(&desc->irq_data, irq_settings_get_trigger_mask(desc));
696
697	irq_put_desc_unlock(desc, flags);
698}
699EXPORT_SYMBOL_GPL(irq_modify_status);
700
701/**
702 *	irq_cpu_online - Invoke all irq_cpu_online functions.
703 *
704 *	Iterate through all irqs and invoke the chip.irq_cpu_online()
705 *	for each.
706 */
707void irq_cpu_online(void)
708{
709	struct irq_desc *desc;
710	struct irq_chip *chip;
711	unsigned long flags;
712	unsigned int irq;
713
714	for_each_active_irq(irq) {
715		desc = irq_to_desc(irq);
716		if (!desc)
717			continue;
718
719		raw_spin_lock_irqsave(&desc->lock, flags);
720
721		chip = irq_data_get_irq_chip(&desc->irq_data);
722		if (chip && chip->irq_cpu_online &&
723		    (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
724		     !irqd_irq_disabled(&desc->irq_data)))
725			chip->irq_cpu_online(&desc->irq_data);
726
727		raw_spin_unlock_irqrestore(&desc->lock, flags);
728	}
729}
730
731/**
732 *	irq_cpu_offline - Invoke all irq_cpu_offline functions.
733 *
734 *	Iterate through all irqs and invoke the chip.irq_cpu_offline()
735 *	for each.
736 */
737void irq_cpu_offline(void)
738{
739	struct irq_desc *desc;
740	struct irq_chip *chip;
741	unsigned long flags;
742	unsigned int irq;
743
744	for_each_active_irq(irq) {
745		desc = irq_to_desc(irq);
746		if (!desc)
747			continue;
748
749		raw_spin_lock_irqsave(&desc->lock, flags);
750
751		chip = irq_data_get_irq_chip(&desc->irq_data);
752		if (chip && chip->irq_cpu_offline &&
753		    (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
754		     !irqd_irq_disabled(&desc->irq_data)))
755			chip->irq_cpu_offline(&desc->irq_data);
756
757		raw_spin_unlock_irqrestore(&desc->lock, flags);
758	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
759}