1/* interrupt.h */ 2#ifndef _LINUX_INTERRUPT_H 3#define _LINUX_INTERRUPT_H 4 5#include <linux/kernel.h> 6#include <linux/linkage.h> 7#include <linux/bitops.h> 8#include <linux/preempt.h> 9#include <linux/cpumask.h> 10#include <linux/irqreturn.h> 11#include <linux/irqnr.h> 12#include <linux/hardirq.h> 13#include <linux/irqflags.h> 14#include <linux/hrtimer.h> 15#include <linux/kref.h> 16#include <linux/workqueue.h> 17 18#include <linux/atomic.h> 19#include <asm/ptrace.h> 20#include <asm/irq.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 an 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 * @thread_flags: flags related to @thread 106 * @thread_mask: bitmask for keeping track of @thread activity 107 * @dir: pointer to the proc/irq/NN/name entry 108 */ 109struct irqaction { 110 irq_handler_t handler; 111 void *dev_id; 112 void __percpu *percpu_dev_id; 113 struct irqaction *next; 114 irq_handler_t thread_fn; 115 struct task_struct *thread; 116 unsigned int irq; 117 unsigned int flags; 118 unsigned long thread_flags; 119 unsigned long thread_mask; 120 const char *name; 121 struct proc_dir_entry *dir; 122} ____cacheline_internodealigned_in_smp; 123 124extern irqreturn_t no_action(int cpl, void *dev_id); 125 126extern int __must_check 127request_threaded_irq(unsigned int irq, irq_handler_t handler, 128 irq_handler_t thread_fn, 129 unsigned long flags, const char *name, void *dev); 130 131static inline int __must_check 132request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags, 133 const char *name, void *dev) 134{ 135 return request_threaded_irq(irq, handler, NULL, flags, name, dev); 136} 137 138extern int __must_check 139request_any_context_irq(unsigned int irq, irq_handler_t handler, 140 unsigned long flags, const char *name, void *dev_id); 141 142extern int __must_check 143request_percpu_irq(unsigned int irq, irq_handler_t handler, 144 const char *devname, void __percpu *percpu_dev_id); 145 146extern void free_irq(unsigned int, void *); 147extern void free_percpu_irq(unsigned int, void __percpu *); 148 149struct device; 150 151extern int __must_check 152devm_request_threaded_irq(struct device *dev, unsigned int irq, 153 irq_handler_t handler, irq_handler_t thread_fn, 154 unsigned long irqflags, const char *devname, 155 void *dev_id); 156 157static inline int __must_check 158devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler, 159 unsigned long irqflags, const char *devname, void *dev_id) 160{ 161 return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags, 162 devname, dev_id); 163} 164 165extern int __must_check 166devm_request_any_context_irq(struct device *dev, unsigned int irq, 167 irq_handler_t handler, unsigned long irqflags, 168 const char *devname, void *dev_id); 169 170extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id); 171 172/* 173 * On lockdep we dont want to enable hardirqs in hardirq 174 * context. Use local_irq_enable_in_hardirq() to annotate 175 * kernel code that has to do this nevertheless (pretty much 176 * the only valid case is for old/broken hardware that is 177 * insanely slow). 178 * 179 * NOTE: in theory this might break fragile code that relies 180 * on hardirq delivery - in practice we dont seem to have such 181 * places left. So the only effect should be slightly increased 182 * irqs-off latencies. 183 */ 184#ifdef CONFIG_LOCKDEP 185# define local_irq_enable_in_hardirq() do { } while (0) 186#else 187# define local_irq_enable_in_hardirq() local_irq_enable() 188#endif 189 190extern void disable_irq_nosync(unsigned int irq); 191extern bool disable_hardirq(unsigned int irq); 192extern void disable_irq(unsigned int irq); 193extern void disable_percpu_irq(unsigned int irq); 194extern void enable_irq(unsigned int irq); 195extern void enable_percpu_irq(unsigned int irq, unsigned int type); 196extern void irq_wake_thread(unsigned int irq, void *dev_id); 197 198/* The following three functions are for the core kernel use only. */ 199extern void suspend_device_irqs(void); 200extern void resume_device_irqs(void); 201 202/** 203 * struct irq_affinity_notify - context for notification of IRQ affinity changes 204 * @irq: Interrupt to which notification applies 205 * @kref: Reference count, for internal use 206 * @work: Work item, for internal use 207 * @notify: Function to be called on change. This will be 208 * called in process context. 209 * @release: Function to be called on release. This will be 210 * called in process context. Once registered, the 211 * structure must only be freed when this function is 212 * called or later. 213 */ 214struct irq_affinity_notify { 215 unsigned int irq; 216 struct kref kref; 217 struct work_struct work; 218 void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask); 219 void (*release)(struct kref *ref); 220}; 221 222#if defined(CONFIG_SMP) 223 224extern cpumask_var_t irq_default_affinity; 225 226/* Internal implementation. Use the helpers below */ 227extern int __irq_set_affinity(unsigned int irq, const struct cpumask *cpumask, 228 bool force); 229 230/** 231 * irq_set_affinity - Set the irq affinity of a given irq 232 * @irq: Interrupt to set affinity 233 * @cpumask: cpumask 234 * 235 * Fails if cpumask does not contain an online CPU 236 */ 237static inline int 238irq_set_affinity(unsigned int irq, const struct cpumask *cpumask) 239{ 240 return __irq_set_affinity(irq, cpumask, false); 241} 242 243/** 244 * irq_force_affinity - Force the irq affinity of a given irq 245 * @irq: Interrupt to set affinity 246 * @cpumask: cpumask 247 * 248 * Same as irq_set_affinity, but without checking the mask against 249 * online cpus. 250 * 251 * Solely for low level cpu hotplug code, where we need to make per 252 * cpu interrupts affine before the cpu becomes online. 253 */ 254static inline int 255irq_force_affinity(unsigned int irq, const struct cpumask *cpumask) 256{ 257 return __irq_set_affinity(irq, cpumask, true); 258} 259 260extern int irq_can_set_affinity(unsigned int irq); 261extern int irq_select_affinity(unsigned int irq); 262 263extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m); 264 265extern int 266irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify); 267 268#else /* CONFIG_SMP */ 269 270static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m) 271{ 272 return -EINVAL; 273} 274 275static inline int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask) 276{ 277 return 0; 278} 279 280static inline int irq_can_set_affinity(unsigned int irq) 281{ 282 return 0; 283} 284 285static inline int irq_select_affinity(unsigned int irq) { return 0; } 286 287static inline int irq_set_affinity_hint(unsigned int irq, 288 const struct cpumask *m) 289{ 290 return -EINVAL; 291} 292 293static inline int 294irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify) 295{ 296 return 0; 297} 298#endif /* CONFIG_SMP */ 299 300/* 301 * Special lockdep variants of irq disabling/enabling. 302 * These should be used for locking constructs that 303 * know that a particular irq context which is disabled, 304 * and which is the only irq-context user of a lock, 305 * that it's safe to take the lock in the irq-disabled 306 * section without disabling hardirqs. 307 * 308 * On !CONFIG_LOCKDEP they are equivalent to the normal 309 * irq disable/enable methods. 310 */ 311static inline void disable_irq_nosync_lockdep(unsigned int irq) 312{ 313 disable_irq_nosync(irq); 314#ifdef CONFIG_LOCKDEP 315 local_irq_disable(); 316#endif 317} 318 319static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags) 320{ 321 disable_irq_nosync(irq); 322#ifdef CONFIG_LOCKDEP 323 local_irq_save(*flags); 324#endif 325} 326 327static inline void disable_irq_lockdep(unsigned int irq) 328{ 329 disable_irq(irq); 330#ifdef CONFIG_LOCKDEP 331 local_irq_disable(); 332#endif 333} 334 335static inline void enable_irq_lockdep(unsigned int irq) 336{ 337#ifdef CONFIG_LOCKDEP 338 local_irq_enable(); 339#endif 340 enable_irq(irq); 341} 342 343static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags) 344{ 345#ifdef CONFIG_LOCKDEP 346 local_irq_restore(*flags); 347#endif 348 enable_irq(irq); 349} 350 351/* IRQ wakeup (PM) control: */ 352extern int irq_set_irq_wake(unsigned int irq, unsigned int on); 353 354static inline int enable_irq_wake(unsigned int irq) 355{ 356 return irq_set_irq_wake(irq, 1); 357} 358 359static inline int disable_irq_wake(unsigned int irq) 360{ 361 return irq_set_irq_wake(irq, 0); 362} 363 364/* 365 * irq_get_irqchip_state/irq_set_irqchip_state specific flags 366 */ 367enum irqchip_irq_state { 368 IRQCHIP_STATE_PENDING, /* Is interrupt pending? */ 369 IRQCHIP_STATE_ACTIVE, /* Is interrupt in progress? */ 370 IRQCHIP_STATE_MASKED, /* Is interrupt masked? */ 371 IRQCHIP_STATE_LINE_LEVEL, /* Is IRQ line high? */ 372}; 373 374extern int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which, 375 bool *state); 376extern int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which, 377 bool state); 378 379#ifdef CONFIG_IRQ_FORCED_THREADING 380extern bool force_irqthreads; 381#else 382#define force_irqthreads (0) 383#endif 384 385#ifndef __ARCH_SET_SOFTIRQ_PENDING 386#define set_softirq_pending(x) (local_softirq_pending() = (x)) 387#define or_softirq_pending(x) (local_softirq_pending() |= (x)) 388#endif 389 390/* Some architectures might implement lazy enabling/disabling of 391 * interrupts. In some cases, such as stop_machine, we might want 392 * to ensure that after a local_irq_disable(), interrupts have 393 * really been disabled in hardware. Such architectures need to 394 * implement the following hook. 395 */ 396#ifndef hard_irq_disable 397#define hard_irq_disable() do { } while(0) 398#endif 399 400/* PLEASE, avoid to allocate new softirqs, if you need not _really_ high 401 frequency threaded job scheduling. For almost all the purposes 402 tasklets are more than enough. F.e. all serial device BHs et 403 al. should be converted to tasklets, not to softirqs. 404 */ 405 406enum 407{ 408 HI_SOFTIRQ=0, 409 TIMER_SOFTIRQ, 410 NET_TX_SOFTIRQ, 411 NET_RX_SOFTIRQ, 412 BLOCK_SOFTIRQ, 413 BLOCK_IOPOLL_SOFTIRQ, 414 TASKLET_SOFTIRQ, 415 SCHED_SOFTIRQ, 416 HRTIMER_SOFTIRQ, 417 RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */ 418 419 NR_SOFTIRQS 420}; 421 422#define SOFTIRQ_STOP_IDLE_MASK (~(1 << RCU_SOFTIRQ)) 423 424/* map softirq index to softirq name. update 'softirq_to_name' in 425 * kernel/softirq.c when adding a new softirq. 426 */ 427extern const char * const softirq_to_name[NR_SOFTIRQS]; 428 429/* softirq mask and active fields moved to irq_cpustat_t in 430 * asm/hardirq.h to get better cache usage. KAO 431 */ 432 433struct softirq_action 434{ 435 void (*action)(struct softirq_action *); 436}; 437 438asmlinkage void do_softirq(void); 439asmlinkage void __do_softirq(void); 440 441#ifdef __ARCH_HAS_DO_SOFTIRQ 442void do_softirq_own_stack(void); 443#else 444static inline void do_softirq_own_stack(void) 445{ 446 __do_softirq(); 447} 448#endif 449 450extern void open_softirq(int nr, void (*action)(struct softirq_action *)); 451extern void softirq_init(void); 452extern void __raise_softirq_irqoff(unsigned int nr); 453 454extern void raise_softirq_irqoff(unsigned int nr); 455extern void raise_softirq(unsigned int nr); 456 457DECLARE_PER_CPU(struct task_struct *, ksoftirqd); 458 459static inline struct task_struct *this_cpu_ksoftirqd(void) 460{ 461 return this_cpu_read(ksoftirqd); 462} 463 464/* Tasklets --- multithreaded analogue of BHs. 465 466 Main feature differing them of generic softirqs: tasklet 467 is running only on one CPU simultaneously. 468 469 Main feature differing them of BHs: different tasklets 470 may be run simultaneously on different CPUs. 471 472 Properties: 473 * If tasklet_schedule() is called, then tasklet is guaranteed 474 to be executed on some cpu at least once after this. 475 * If the tasklet is already scheduled, but its execution is still not 476 started, it will be executed only once. 477 * If this tasklet is already running on another CPU (or schedule is called 478 from tasklet itself), it is rescheduled for later. 479 * Tasklet is strictly serialized wrt itself, but not 480 wrt another tasklets. If client needs some intertask synchronization, 481 he makes it with spinlocks. 482 */ 483 484struct tasklet_struct 485{ 486 struct tasklet_struct *next; 487 unsigned long state; 488 atomic_t count; 489 void (*func)(unsigned long); 490 unsigned long data; 491}; 492 493#define DECLARE_TASKLET(name, func, data) \ 494struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data } 495 496#define DECLARE_TASKLET_DISABLED(name, func, data) \ 497struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data } 498 499 500enum 501{ 502 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */ 503 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */ 504}; 505 506#ifdef CONFIG_SMP 507static inline int tasklet_trylock(struct tasklet_struct *t) 508{ 509 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state); 510} 511 512static inline void tasklet_unlock(struct tasklet_struct *t) 513{ 514 smp_mb__before_atomic(); 515 clear_bit(TASKLET_STATE_RUN, &(t)->state); 516} 517 518static inline void tasklet_unlock_wait(struct tasklet_struct *t) 519{ 520 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); } 521} 522#else 523#define tasklet_trylock(t) 1 524#define tasklet_unlock_wait(t) do { } while (0) 525#define tasklet_unlock(t) do { } while (0) 526#endif 527 528extern void __tasklet_schedule(struct tasklet_struct *t); 529 530static inline void tasklet_schedule(struct tasklet_struct *t) 531{ 532 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) 533 __tasklet_schedule(t); 534} 535 536extern void __tasklet_hi_schedule(struct tasklet_struct *t); 537 538static inline void tasklet_hi_schedule(struct tasklet_struct *t) 539{ 540 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) 541 __tasklet_hi_schedule(t); 542} 543 544extern void __tasklet_hi_schedule_first(struct tasklet_struct *t); 545 546/* 547 * This version avoids touching any other tasklets. Needed for kmemcheck 548 * in order not to take any page faults while enqueueing this tasklet; 549 * consider VERY carefully whether you really need this or 550 * tasklet_hi_schedule()... 551 */ 552static inline void tasklet_hi_schedule_first(struct tasklet_struct *t) 553{ 554 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) 555 __tasklet_hi_schedule_first(t); 556} 557 558 559static inline void tasklet_disable_nosync(struct tasklet_struct *t) 560{ 561 atomic_inc(&t->count); 562 smp_mb__after_atomic(); 563} 564 565static inline void tasklet_disable(struct tasklet_struct *t) 566{ 567 tasklet_disable_nosync(t); 568 tasklet_unlock_wait(t); 569 smp_mb(); 570} 571 572static inline void tasklet_enable(struct tasklet_struct *t) 573{ 574 smp_mb__before_atomic(); 575 atomic_dec(&t->count); 576} 577 578extern void tasklet_kill(struct tasklet_struct *t); 579extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu); 580extern void tasklet_init(struct tasklet_struct *t, 581 void (*func)(unsigned long), unsigned long data); 582 583struct tasklet_hrtimer { 584 struct hrtimer timer; 585 struct tasklet_struct tasklet; 586 enum hrtimer_restart (*function)(struct hrtimer *); 587}; 588 589extern void 590tasklet_hrtimer_init(struct tasklet_hrtimer *ttimer, 591 enum hrtimer_restart (*function)(struct hrtimer *), 592 clockid_t which_clock, enum hrtimer_mode mode); 593 594static inline 595int tasklet_hrtimer_start(struct tasklet_hrtimer *ttimer, ktime_t time, 596 const enum hrtimer_mode mode) 597{ 598 return hrtimer_start(&ttimer->timer, time, mode); 599} 600 601static inline 602void tasklet_hrtimer_cancel(struct tasklet_hrtimer *ttimer) 603{ 604 hrtimer_cancel(&ttimer->timer); 605 tasklet_kill(&ttimer->tasklet); 606} 607 608/* 609 * Autoprobing for irqs: 610 * 611 * probe_irq_on() and probe_irq_off() provide robust primitives 612 * for accurate IRQ probing during kernel initialization. They are 613 * reasonably simple to use, are not "fooled" by spurious interrupts, 614 * and, unlike other attempts at IRQ probing, they do not get hung on 615 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards). 616 * 617 * For reasonably foolproof probing, use them as follows: 618 * 619 * 1. clear and/or mask the device's internal interrupt. 620 * 2. sti(); 621 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs 622 * 4. enable the device and cause it to trigger an interrupt. 623 * 5. wait for the device to interrupt, using non-intrusive polling or a delay. 624 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple 625 * 7. service the device to clear its pending interrupt. 626 * 8. loop again if paranoia is required. 627 * 628 * probe_irq_on() returns a mask of allocated irq's. 629 * 630 * probe_irq_off() takes the mask as a parameter, 631 * and returns the irq number which occurred, 632 * or zero if none occurred, or a negative irq number 633 * if more than one irq occurred. 634 */ 635 636#if !defined(CONFIG_GENERIC_IRQ_PROBE) 637static inline unsigned long probe_irq_on(void) 638{ 639 return 0; 640} 641static inline int probe_irq_off(unsigned long val) 642{ 643 return 0; 644} 645static inline unsigned int probe_irq_mask(unsigned long val) 646{ 647 return 0; 648} 649#else 650extern unsigned long probe_irq_on(void); /* returns 0 on failure */ 651extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */ 652extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */ 653#endif 654 655#ifdef CONFIG_PROC_FS 656/* Initialize /proc/irq/ */ 657extern void init_irq_proc(void); 658#else 659static inline void init_irq_proc(void) 660{ 661} 662#endif 663 664struct seq_file; 665int show_interrupts(struct seq_file *p, void *v); 666int arch_show_interrupts(struct seq_file *p, int prec); 667 668extern int early_irq_init(void); 669extern int arch_probe_nr_irqs(void); 670extern int arch_early_irq_init(void); 671 672#endif 673