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1/* SPDX-License-Identifier: GPL-2.0 */ 2/* interrupt.h */ 3#ifndef _LINUX_INTERRUPT_H 4#define _LINUX_INTERRUPT_H 5 6#include <linux/kernel.h> 7#include <linux/bitops.h> 8#include <linux/cpumask.h> 9#include <linux/irqreturn.h> 10#include <linux/irqnr.h> 11#include <linux/hardirq.h> 12#include <linux/irqflags.h> 13#include <linux/hrtimer.h> 14#include <linux/kref.h> 15#include <linux/workqueue.h> 16 17#include <linux/atomic.h> 18#include <asm/ptrace.h> 19#include <asm/irq.h> 20#include <asm/sections.h> 21 22/* 23 * These correspond to the IORESOURCE_IRQ_* defines in 24 * linux/ioport.h to select the interrupt line behaviour. When 25 * requesting an interrupt without specifying a IRQF_TRIGGER, the 26 * setting should be assumed to be "as already configured", which 27 * may be as per machine or firmware initialisation. 28 */ 29#define IRQF_TRIGGER_NONE 0x00000000 30#define IRQF_TRIGGER_RISING 0x00000001 31#define IRQF_TRIGGER_FALLING 0x00000002 32#define IRQF_TRIGGER_HIGH 0x00000004 33#define IRQF_TRIGGER_LOW 0x00000008 34#define IRQF_TRIGGER_MASK (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \ 35 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING) 36#define IRQF_TRIGGER_PROBE 0x00000010 37 38/* 39 * These flags used only by the kernel as part of the 40 * irq handling routines. 41 * 42 * IRQF_SHARED - allow sharing the irq among several devices 43 * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur 44 * IRQF_TIMER - Flag to mark this interrupt as timer interrupt 45 * IRQF_PERCPU - Interrupt is per cpu 46 * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing 47 * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is 48 * registered first in a shared interrupt is considered for 49 * performance reasons) 50 * IRQF_ONESHOT - Interrupt is not reenabled after the hardirq handler finished. 51 * Used by threaded interrupts which need to keep the 52 * irq line disabled until the threaded handler has been run. 53 * IRQF_NO_SUSPEND - Do not disable this IRQ during suspend. Does not guarantee 54 * that this interrupt will wake the system from a suspended 55 * state. See Documentation/power/suspend-and-interrupts.txt 56 * IRQF_FORCE_RESUME - Force enable it on resume even if IRQF_NO_SUSPEND is set 57 * IRQF_NO_THREAD - Interrupt cannot be threaded 58 * IRQF_EARLY_RESUME - Resume IRQ early during syscore instead of at device 59 * resume time. 60 * IRQF_COND_SUSPEND - If the IRQ is shared with a NO_SUSPEND user, execute this 61 * interrupt handler after suspending interrupts. For system 62 * wakeup devices users need to implement wakeup detection in 63 * their interrupt handlers. 64 */ 65#define IRQF_SHARED 0x00000080 66#define IRQF_PROBE_SHARED 0x00000100 67#define __IRQF_TIMER 0x00000200 68#define IRQF_PERCPU 0x00000400 69#define IRQF_NOBALANCING 0x00000800 70#define IRQF_IRQPOLL 0x00001000 71#define IRQF_ONESHOT 0x00002000 72#define IRQF_NO_SUSPEND 0x00004000 73#define IRQF_FORCE_RESUME 0x00008000 74#define IRQF_NO_THREAD 0x00010000 75#define IRQF_EARLY_RESUME 0x00020000 76#define IRQF_COND_SUSPEND 0x00040000 77 78#define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD) 79 80/* 81 * These values can be returned by request_any_context_irq() and 82 * describe the context the interrupt will be run in. 83 * 84 * IRQC_IS_HARDIRQ - interrupt runs in hardirq context 85 * IRQC_IS_NESTED - interrupt runs in a nested threaded context 86 */ 87enum { 88 IRQC_IS_HARDIRQ = 0, 89 IRQC_IS_NESTED, 90}; 91 92typedef irqreturn_t (*irq_handler_t)(int, void *); 93 94/** 95 * struct irqaction - per interrupt action descriptor 96 * @handler: interrupt handler function 97 * @name: name of the device 98 * @dev_id: cookie to identify the device 99 * @percpu_dev_id: cookie to identify the device 100 * @next: pointer to the next irqaction for shared interrupts 101 * @irq: interrupt number 102 * @flags: flags (see IRQF_* above) 103 * @thread_fn: interrupt handler function for threaded interrupts 104 * @thread: thread pointer for threaded interrupts 105 * @secondary: pointer to secondary irqaction (force threading) 106 * @thread_flags: flags related to @thread 107 * @thread_mask: bitmask for keeping track of @thread activity 108 * @dir: pointer to the proc/irq/NN/name entry 109 */ 110struct irqaction { 111 irq_handler_t handler; 112 void *dev_id; 113 void __percpu *percpu_dev_id; 114 struct irqaction *next; 115 irq_handler_t thread_fn; 116 struct task_struct *thread; 117 struct irqaction *secondary; 118 unsigned int irq; 119 unsigned int flags; 120 unsigned long thread_flags; 121 unsigned long thread_mask; 122 const char *name; 123 struct proc_dir_entry *dir; 124} ____cacheline_internodealigned_in_smp; 125 126extern irqreturn_t no_action(int cpl, void *dev_id); 127 128/* 129 * If a (PCI) device interrupt is not connected we set dev->irq to 130 * IRQ_NOTCONNECTED. This causes request_irq() to fail with -ENOTCONN, so we 131 * can distingiush that case from other error returns. 132 * 133 * 0x80000000 is guaranteed to be outside the available range of interrupts 134 * and easy to distinguish from other possible incorrect values. 135 */ 136#define IRQ_NOTCONNECTED (1U << 31) 137 138extern int __must_check 139request_threaded_irq(unsigned int irq, irq_handler_t handler, 140 irq_handler_t thread_fn, 141 unsigned long flags, const char *name, void *dev); 142 143static inline int __must_check 144request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags, 145 const char *name, void *dev) 146{ 147 return request_threaded_irq(irq, handler, NULL, flags, name, dev); 148} 149 150extern int __must_check 151request_any_context_irq(unsigned int irq, irq_handler_t handler, 152 unsigned long flags, const char *name, void *dev_id); 153 154extern int __must_check 155__request_percpu_irq(unsigned int irq, irq_handler_t handler, 156 unsigned long flags, const char *devname, 157 void __percpu *percpu_dev_id); 158 159static inline int __must_check 160request_percpu_irq(unsigned int irq, irq_handler_t handler, 161 const char *devname, void __percpu *percpu_dev_id) 162{ 163 return __request_percpu_irq(irq, handler, 0, 164 devname, percpu_dev_id); 165} 166 167extern const void *free_irq(unsigned int, void *); 168extern void free_percpu_irq(unsigned int, void __percpu *); 169 170struct device; 171 172extern int __must_check 173devm_request_threaded_irq(struct device *dev, unsigned int irq, 174 irq_handler_t handler, irq_handler_t thread_fn, 175 unsigned long irqflags, const char *devname, 176 void *dev_id); 177 178static inline int __must_check 179devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler, 180 unsigned long irqflags, const char *devname, void *dev_id) 181{ 182 return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags, 183 devname, dev_id); 184} 185 186extern int __must_check 187devm_request_any_context_irq(struct device *dev, unsigned int irq, 188 irq_handler_t handler, unsigned long irqflags, 189 const char *devname, void *dev_id); 190 191extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id); 192 193/* 194 * On lockdep we dont want to enable hardirqs in hardirq 195 * context. Use local_irq_enable_in_hardirq() to annotate 196 * kernel code that has to do this nevertheless (pretty much 197 * the only valid case is for old/broken hardware that is 198 * insanely slow). 199 * 200 * NOTE: in theory this might break fragile code that relies 201 * on hardirq delivery - in practice we dont seem to have such 202 * places left. So the only effect should be slightly increased 203 * irqs-off latencies. 204 */ 205#ifdef CONFIG_LOCKDEP 206# define local_irq_enable_in_hardirq() do { } while (0) 207#else 208# define local_irq_enable_in_hardirq() local_irq_enable() 209#endif 210 211extern void disable_irq_nosync(unsigned int irq); 212extern bool disable_hardirq(unsigned int irq); 213extern void disable_irq(unsigned int irq); 214extern void disable_percpu_irq(unsigned int irq); 215extern void enable_irq(unsigned int irq); 216extern void enable_percpu_irq(unsigned int irq, unsigned int type); 217extern bool irq_percpu_is_enabled(unsigned int irq); 218extern void irq_wake_thread(unsigned int irq, void *dev_id); 219 220/* The following three functions are for the core kernel use only. */ 221extern void suspend_device_irqs(void); 222extern void resume_device_irqs(void); 223 224/** 225 * struct irq_affinity_notify - context for notification of IRQ affinity changes 226 * @irq: Interrupt to which notification applies 227 * @kref: Reference count, for internal use 228 * @work: Work item, for internal use 229 * @notify: Function to be called on change. This will be 230 * called in process context. 231 * @release: Function to be called on release. This will be 232 * called in process context. Once registered, the 233 * structure must only be freed when this function is 234 * called or later. 235 */ 236struct irq_affinity_notify { 237 unsigned int irq; 238 struct kref kref; 239 struct work_struct work; 240 void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask); 241 void (*release)(struct kref *ref); 242}; 243 244/** 245 * struct irq_affinity - Description for automatic irq affinity assignements 246 * @pre_vectors: Don't apply affinity to @pre_vectors at beginning of 247 * the MSI(-X) vector space 248 * @post_vectors: Don't apply affinity to @post_vectors at end of 249 * the MSI(-X) vector space 250 * @nr_sets: Length of passed in *sets array 251 * @sets: Number of affinitized sets 252 */ 253struct irq_affinity { 254 int pre_vectors; 255 int post_vectors; 256 int nr_sets; 257 int *sets; 258}; 259 260/** 261 * struct irq_affinity_desc - Interrupt affinity descriptor 262 * @mask: cpumask to hold the affinity assignment 263 * @is_managed: 1 if the interrupt is managed internally 264 */ 265struct irq_affinity_desc { 266 struct cpumask mask; 267 unsigned int is_managed : 1; 268}; 269 270#if defined(CONFIG_SMP) 271 272extern cpumask_var_t irq_default_affinity; 273 274/* Internal implementation. Use the helpers below */ 275extern int __irq_set_affinity(unsigned int irq, const struct cpumask *cpumask, 276 bool force); 277 278/** 279 * irq_set_affinity - Set the irq affinity of a given irq 280 * @irq: Interrupt to set affinity 281 * @cpumask: cpumask 282 * 283 * Fails if cpumask does not contain an online CPU 284 */ 285static inline int 286irq_set_affinity(unsigned int irq, const struct cpumask *cpumask) 287{ 288 return __irq_set_affinity(irq, cpumask, false); 289} 290 291/** 292 * irq_force_affinity - Force the irq affinity of a given irq 293 * @irq: Interrupt to set affinity 294 * @cpumask: cpumask 295 * 296 * Same as irq_set_affinity, but without checking the mask against 297 * online cpus. 298 * 299 * Solely for low level cpu hotplug code, where we need to make per 300 * cpu interrupts affine before the cpu becomes online. 301 */ 302static inline int 303irq_force_affinity(unsigned int irq, const struct cpumask *cpumask) 304{ 305 return __irq_set_affinity(irq, cpumask, true); 306} 307 308extern int irq_can_set_affinity(unsigned int irq); 309extern int irq_select_affinity(unsigned int irq); 310 311extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m); 312 313extern int 314irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify); 315 316struct irq_affinity_desc * 317irq_create_affinity_masks(int nvec, const struct irq_affinity *affd); 318 319int irq_calc_affinity_vectors(int minvec, int maxvec, const struct irq_affinity *affd); 320 321#else /* CONFIG_SMP */ 322 323static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m) 324{ 325 return -EINVAL; 326} 327 328static inline int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask) 329{ 330 return 0; 331} 332 333static inline int irq_can_set_affinity(unsigned int irq) 334{ 335 return 0; 336} 337 338static inline int irq_select_affinity(unsigned int irq) { return 0; } 339 340static inline int irq_set_affinity_hint(unsigned int irq, 341 const struct cpumask *m) 342{ 343 return -EINVAL; 344} 345 346static inline int 347irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify) 348{ 349 return 0; 350} 351 352static inline struct irq_affinity_desc * 353irq_create_affinity_masks(int nvec, const struct irq_affinity *affd) 354{ 355 return NULL; 356} 357 358static inline int 359irq_calc_affinity_vectors(int minvec, int maxvec, const struct irq_affinity *affd) 360{ 361 return maxvec; 362} 363 364#endif /* CONFIG_SMP */ 365 366/* 367 * Special lockdep variants of irq disabling/enabling. 368 * These should be used for locking constructs that 369 * know that a particular irq context which is disabled, 370 * and which is the only irq-context user of a lock, 371 * that it's safe to take the lock in the irq-disabled 372 * section without disabling hardirqs. 373 * 374 * On !CONFIG_LOCKDEP they are equivalent to the normal 375 * irq disable/enable methods. 376 */ 377static inline void disable_irq_nosync_lockdep(unsigned int irq) 378{ 379 disable_irq_nosync(irq); 380#ifdef CONFIG_LOCKDEP 381 local_irq_disable(); 382#endif 383} 384 385static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags) 386{ 387 disable_irq_nosync(irq); 388#ifdef CONFIG_LOCKDEP 389 local_irq_save(*flags); 390#endif 391} 392 393static inline void disable_irq_lockdep(unsigned int irq) 394{ 395 disable_irq(irq); 396#ifdef CONFIG_LOCKDEP 397 local_irq_disable(); 398#endif 399} 400 401static inline void enable_irq_lockdep(unsigned int irq) 402{ 403#ifdef CONFIG_LOCKDEP 404 local_irq_enable(); 405#endif 406 enable_irq(irq); 407} 408 409static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags) 410{ 411#ifdef CONFIG_LOCKDEP 412 local_irq_restore(*flags); 413#endif 414 enable_irq(irq); 415} 416 417/* IRQ wakeup (PM) control: */ 418extern int irq_set_irq_wake(unsigned int irq, unsigned int on); 419 420static inline int enable_irq_wake(unsigned int irq) 421{ 422 return irq_set_irq_wake(irq, 1); 423} 424 425static inline int disable_irq_wake(unsigned int irq) 426{ 427 return irq_set_irq_wake(irq, 0); 428} 429 430/* 431 * irq_get_irqchip_state/irq_set_irqchip_state specific flags 432 */ 433enum irqchip_irq_state { 434 IRQCHIP_STATE_PENDING, /* Is interrupt pending? */ 435 IRQCHIP_STATE_ACTIVE, /* Is interrupt in progress? */ 436 IRQCHIP_STATE_MASKED, /* Is interrupt masked? */ 437 IRQCHIP_STATE_LINE_LEVEL, /* Is IRQ line high? */ 438}; 439 440extern int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which, 441 bool *state); 442extern int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which, 443 bool state); 444 445#ifdef CONFIG_IRQ_FORCED_THREADING 446extern bool force_irqthreads; 447#else 448#define force_irqthreads (0) 449#endif 450 451#ifndef local_softirq_pending 452 453#ifndef local_softirq_pending_ref 454#define local_softirq_pending_ref irq_stat.__softirq_pending 455#endif 456 457#define local_softirq_pending() (__this_cpu_read(local_softirq_pending_ref)) 458#define set_softirq_pending(x) (__this_cpu_write(local_softirq_pending_ref, (x))) 459#define or_softirq_pending(x) (__this_cpu_or(local_softirq_pending_ref, (x))) 460 461#endif /* local_softirq_pending */ 462 463/* Some architectures might implement lazy enabling/disabling of 464 * interrupts. In some cases, such as stop_machine, we might want 465 * to ensure that after a local_irq_disable(), interrupts have 466 * really been disabled in hardware. Such architectures need to 467 * implement the following hook. 468 */ 469#ifndef hard_irq_disable 470#define hard_irq_disable() do { } while(0) 471#endif 472 473/* PLEASE, avoid to allocate new softirqs, if you need not _really_ high 474 frequency threaded job scheduling. For almost all the purposes 475 tasklets are more than enough. F.e. all serial device BHs et 476 al. should be converted to tasklets, not to softirqs. 477 */ 478 479enum 480{ 481 HI_SOFTIRQ=0, 482 TIMER_SOFTIRQ, 483 NET_TX_SOFTIRQ, 484 NET_RX_SOFTIRQ, 485 BLOCK_SOFTIRQ, 486 IRQ_POLL_SOFTIRQ, 487 TASKLET_SOFTIRQ, 488 SCHED_SOFTIRQ, 489 HRTIMER_SOFTIRQ, /* Unused, but kept as tools rely on the 490 numbering. Sigh! */ 491 RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */ 492 493 NR_SOFTIRQS 494}; 495 496#define SOFTIRQ_STOP_IDLE_MASK (~(1 << RCU_SOFTIRQ)) 497 498/* map softirq index to softirq name. update 'softirq_to_name' in 499 * kernel/softirq.c when adding a new softirq. 500 */ 501extern const char * const softirq_to_name[NR_SOFTIRQS]; 502 503/* softirq mask and active fields moved to irq_cpustat_t in 504 * asm/hardirq.h to get better cache usage. KAO 505 */ 506 507struct softirq_action 508{ 509 void (*action)(struct softirq_action *); 510}; 511 512asmlinkage void do_softirq(void); 513asmlinkage void __do_softirq(void); 514 515#ifdef __ARCH_HAS_DO_SOFTIRQ 516void do_softirq_own_stack(void); 517#else 518static inline void do_softirq_own_stack(void) 519{ 520 __do_softirq(); 521} 522#endif 523 524extern void open_softirq(int nr, void (*action)(struct softirq_action *)); 525extern void softirq_init(void); 526extern void __raise_softirq_irqoff(unsigned int nr); 527 528extern void raise_softirq_irqoff(unsigned int nr); 529extern void raise_softirq(unsigned int nr); 530 531DECLARE_PER_CPU(struct task_struct *, ksoftirqd); 532 533static inline struct task_struct *this_cpu_ksoftirqd(void) 534{ 535 return this_cpu_read(ksoftirqd); 536} 537 538/* Tasklets --- multithreaded analogue of BHs. 539 540 Main feature differing them of generic softirqs: tasklet 541 is running only on one CPU simultaneously. 542 543 Main feature differing them of BHs: different tasklets 544 may be run simultaneously on different CPUs. 545 546 Properties: 547 * If tasklet_schedule() is called, then tasklet is guaranteed 548 to be executed on some cpu at least once after this. 549 * If the tasklet is already scheduled, but its execution is still not 550 started, it will be executed only once. 551 * If this tasklet is already running on another CPU (or schedule is called 552 from tasklet itself), it is rescheduled for later. 553 * Tasklet is strictly serialized wrt itself, but not 554 wrt another tasklets. If client needs some intertask synchronization, 555 he makes it with spinlocks. 556 */ 557 558struct tasklet_struct 559{ 560 struct tasklet_struct *next; 561 unsigned long state; 562 atomic_t count; 563 void (*func)(unsigned long); 564 unsigned long data; 565}; 566 567#define DECLARE_TASKLET(name, func, data) \ 568struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data } 569 570#define DECLARE_TASKLET_DISABLED(name, func, data) \ 571struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data } 572 573 574enum 575{ 576 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */ 577 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */ 578}; 579 580#ifdef CONFIG_SMP 581static inline int tasklet_trylock(struct tasklet_struct *t) 582{ 583 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state); 584} 585 586static inline void tasklet_unlock(struct tasklet_struct *t) 587{ 588 smp_mb__before_atomic(); 589 clear_bit(TASKLET_STATE_RUN, &(t)->state); 590} 591 592static inline void tasklet_unlock_wait(struct tasklet_struct *t) 593{ 594 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); } 595} 596#else 597#define tasklet_trylock(t) 1 598#define tasklet_unlock_wait(t) do { } while (0) 599#define tasklet_unlock(t) do { } while (0) 600#endif 601 602extern void __tasklet_schedule(struct tasklet_struct *t); 603 604static inline void tasklet_schedule(struct tasklet_struct *t) 605{ 606 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) 607 __tasklet_schedule(t); 608} 609 610extern void __tasklet_hi_schedule(struct tasklet_struct *t); 611 612static inline void tasklet_hi_schedule(struct tasklet_struct *t) 613{ 614 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) 615 __tasklet_hi_schedule(t); 616} 617 618static inline void tasklet_disable_nosync(struct tasklet_struct *t) 619{ 620 atomic_inc(&t->count); 621 smp_mb__after_atomic(); 622} 623 624static inline void tasklet_disable(struct tasklet_struct *t) 625{ 626 tasklet_disable_nosync(t); 627 tasklet_unlock_wait(t); 628 smp_mb(); 629} 630 631static inline void tasklet_enable(struct tasklet_struct *t) 632{ 633 smp_mb__before_atomic(); 634 atomic_dec(&t->count); 635} 636 637extern void tasklet_kill(struct tasklet_struct *t); 638extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu); 639extern void tasklet_init(struct tasklet_struct *t, 640 void (*func)(unsigned long), unsigned long data); 641 642struct tasklet_hrtimer { 643 struct hrtimer timer; 644 struct tasklet_struct tasklet; 645 enum hrtimer_restart (*function)(struct hrtimer *); 646}; 647 648extern void 649tasklet_hrtimer_init(struct tasklet_hrtimer *ttimer, 650 enum hrtimer_restart (*function)(struct hrtimer *), 651 clockid_t which_clock, enum hrtimer_mode mode); 652 653static inline 654void tasklet_hrtimer_start(struct tasklet_hrtimer *ttimer, ktime_t time, 655 const enum hrtimer_mode mode) 656{ 657 hrtimer_start(&ttimer->timer, time, mode); 658} 659 660static inline 661void tasklet_hrtimer_cancel(struct tasklet_hrtimer *ttimer) 662{ 663 hrtimer_cancel(&ttimer->timer); 664 tasklet_kill(&ttimer->tasklet); 665} 666 667/* 668 * Autoprobing for irqs: 669 * 670 * probe_irq_on() and probe_irq_off() provide robust primitives 671 * for accurate IRQ probing during kernel initialization. They are 672 * reasonably simple to use, are not "fooled" by spurious interrupts, 673 * and, unlike other attempts at IRQ probing, they do not get hung on 674 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards). 675 * 676 * For reasonably foolproof probing, use them as follows: 677 * 678 * 1. clear and/or mask the device's internal interrupt. 679 * 2. sti(); 680 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs 681 * 4. enable the device and cause it to trigger an interrupt. 682 * 5. wait for the device to interrupt, using non-intrusive polling or a delay. 683 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple 684 * 7. service the device to clear its pending interrupt. 685 * 8. loop again if paranoia is required. 686 * 687 * probe_irq_on() returns a mask of allocated irq's. 688 * 689 * probe_irq_off() takes the mask as a parameter, 690 * and returns the irq number which occurred, 691 * or zero if none occurred, or a negative irq number 692 * if more than one irq occurred. 693 */ 694 695#if !defined(CONFIG_GENERIC_IRQ_PROBE) 696static inline unsigned long probe_irq_on(void) 697{ 698 return 0; 699} 700static inline int probe_irq_off(unsigned long val) 701{ 702 return 0; 703} 704static inline unsigned int probe_irq_mask(unsigned long val) 705{ 706 return 0; 707} 708#else 709extern unsigned long probe_irq_on(void); /* returns 0 on failure */ 710extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */ 711extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */ 712#endif 713 714#ifdef CONFIG_PROC_FS 715/* Initialize /proc/irq/ */ 716extern void init_irq_proc(void); 717#else 718static inline void init_irq_proc(void) 719{ 720} 721#endif 722 723#ifdef CONFIG_IRQ_TIMINGS 724void irq_timings_enable(void); 725void irq_timings_disable(void); 726u64 irq_timings_next_event(u64 now); 727#endif 728 729struct seq_file; 730int show_interrupts(struct seq_file *p, void *v); 731int arch_show_interrupts(struct seq_file *p, int prec); 732 733extern int early_irq_init(void); 734extern int arch_probe_nr_irqs(void); 735extern int arch_early_irq_init(void); 736 737/* 738 * We want to know which function is an entrypoint of a hardirq or a softirq. 739 */ 740#define __irq_entry __attribute__((__section__(".irqentry.text"))) 741#define __softirq_entry \ 742 __attribute__((__section__(".softirqentry.text"))) 743 744#endif