2 #ifndef _LINUX_INTERRUPT_H
3 #define _LINUX_INTERRUPT_H
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/sched.h>
14 #include <linux/irqflags.h>
15 #include <linux/smp.h>
16 #include <linux/percpu.h>
18 #include <asm/atomic.h>
19 #include <asm/ptrace.h>
20 #include <asm/system.h>
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.
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
39 * These flags used only by the kernel as part of the
40 * irq handling routines.
42 * IRQF_DISABLED - keep irqs disabled when calling the action handler
43 * IRQF_SAMPLE_RANDOM - irq is used to feed the random generator
44 * IRQF_SHARED - allow sharing the irq among several devices
45 * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
46 * IRQF_TIMER - Flag to mark this interrupt as timer interrupt
47 * IRQF_PERCPU - Interrupt is per cpu
48 * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
49 * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
50 * registered first in an shared interrupt is considered for
51 * performance reasons)
53 #define IRQF_DISABLED 0x00000020
54 #define IRQF_SAMPLE_RANDOM 0x00000040
55 #define IRQF_SHARED 0x00000080
56 #define IRQF_PROBE_SHARED 0x00000100
57 #define IRQF_TIMER 0x00000200
58 #define IRQF_PERCPU 0x00000400
59 #define IRQF_NOBALANCING 0x00000800
60 #define IRQF_IRQPOLL 0x00001000
62 typedef irqreturn_t (*irq_handler_t)(int, void *);
65 * struct irqaction - per interrupt action descriptor
66 * @handler: interrupt handler function
67 * @flags: flags (see IRQF_* above)
68 * @mask: no comment as it is useless and about to be removed
69 * @name: name of the device
70 * @dev_id: cookie to identify the device
71 * @next: pointer to the next irqaction for shared interrupts
72 * @irq: interrupt number
73 * @dir: pointer to the proc/irq/NN/name entry
76 irq_handler_t handler;
81 struct irqaction *next;
83 struct proc_dir_entry *dir;
86 extern irqreturn_t no_action(int cpl, void *dev_id);
87 extern int __must_check request_irq(unsigned int, irq_handler_t handler,
88 unsigned long, const char *, void *);
89 extern void free_irq(unsigned int, void *);
93 extern int __must_check devm_request_irq(struct device *dev, unsigned int irq,
94 irq_handler_t handler, unsigned long irqflags,
95 const char *devname, void *dev_id);
96 extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
99 * On lockdep we dont want to enable hardirqs in hardirq
100 * context. Use local_irq_enable_in_hardirq() to annotate
101 * kernel code that has to do this nevertheless (pretty much
102 * the only valid case is for old/broken hardware that is
105 * NOTE: in theory this might break fragile code that relies
106 * on hardirq delivery - in practice we dont seem to have such
107 * places left. So the only effect should be slightly increased
108 * irqs-off latencies.
110 #ifdef CONFIG_LOCKDEP
111 # define local_irq_enable_in_hardirq() do { } while (0)
113 # define local_irq_enable_in_hardirq() local_irq_enable()
116 extern void disable_irq_nosync(unsigned int irq);
117 extern void disable_irq(unsigned int irq);
118 extern void enable_irq(unsigned int irq);
120 #if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
122 extern cpumask_var_t irq_default_affinity;
124 extern int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask);
125 extern int irq_can_set_affinity(unsigned int irq);
126 extern int irq_select_affinity(unsigned int irq);
128 #else /* CONFIG_SMP */
130 static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
135 static inline int irq_can_set_affinity(unsigned int irq)
140 static inline int irq_select_affinity(unsigned int irq) { return 0; }
142 #endif /* CONFIG_SMP && CONFIG_GENERIC_HARDIRQS */
144 #ifdef CONFIG_GENERIC_HARDIRQS
146 * Special lockdep variants of irq disabling/enabling.
147 * These should be used for locking constructs that
148 * know that a particular irq context which is disabled,
149 * and which is the only irq-context user of a lock,
150 * that it's safe to take the lock in the irq-disabled
151 * section without disabling hardirqs.
153 * On !CONFIG_LOCKDEP they are equivalent to the normal
154 * irq disable/enable methods.
156 static inline void disable_irq_nosync_lockdep(unsigned int irq)
158 disable_irq_nosync(irq);
159 #ifdef CONFIG_LOCKDEP
164 static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
166 disable_irq_nosync(irq);
167 #ifdef CONFIG_LOCKDEP
168 local_irq_save(*flags);
172 static inline void disable_irq_lockdep(unsigned int irq)
175 #ifdef CONFIG_LOCKDEP
180 static inline void enable_irq_lockdep(unsigned int irq)
182 #ifdef CONFIG_LOCKDEP
188 static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
190 #ifdef CONFIG_LOCKDEP
191 local_irq_restore(*flags);
196 /* IRQ wakeup (PM) control: */
197 extern int set_irq_wake(unsigned int irq, unsigned int on);
199 static inline int enable_irq_wake(unsigned int irq)
201 return set_irq_wake(irq, 1);
204 static inline int disable_irq_wake(unsigned int irq)
206 return set_irq_wake(irq, 0);
209 #else /* !CONFIG_GENERIC_HARDIRQS */
211 * NOTE: non-genirq architectures, if they want to support the lock
212 * validator need to define the methods below in their asm/irq.h
213 * files, under an #ifdef CONFIG_LOCKDEP section.
215 #ifndef CONFIG_LOCKDEP
216 # define disable_irq_nosync_lockdep(irq) disable_irq_nosync(irq)
217 # define disable_irq_nosync_lockdep_irqsave(irq, flags) \
218 disable_irq_nosync(irq)
219 # define disable_irq_lockdep(irq) disable_irq(irq)
220 # define enable_irq_lockdep(irq) enable_irq(irq)
221 # define enable_irq_lockdep_irqrestore(irq, flags) \
225 static inline int enable_irq_wake(unsigned int irq)
230 static inline int disable_irq_wake(unsigned int irq)
234 #endif /* CONFIG_GENERIC_HARDIRQS */
236 #ifndef __ARCH_SET_SOFTIRQ_PENDING
237 #define set_softirq_pending(x) (local_softirq_pending() = (x))
238 #define or_softirq_pending(x) (local_softirq_pending() |= (x))
241 /* Some architectures might implement lazy enabling/disabling of
242 * interrupts. In some cases, such as stop_machine, we might want
243 * to ensure that after a local_irq_disable(), interrupts have
244 * really been disabled in hardware. Such architectures need to
245 * implement the following hook.
247 #ifndef hard_irq_disable
248 #define hard_irq_disable() do { } while(0)
251 /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
252 frequency threaded job scheduling. For almost all the purposes
253 tasklets are more than enough. F.e. all serial device BHs et
254 al. should be converted to tasklets, not to softirqs.
267 RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */
272 /* softirq mask and active fields moved to irq_cpustat_t in
273 * asm/hardirq.h to get better cache usage. KAO
276 struct softirq_action
278 void (*action)(struct softirq_action *);
281 asmlinkage void do_softirq(void);
282 asmlinkage void __do_softirq(void);
283 extern void open_softirq(int nr, void (*action)(struct softirq_action *));
284 extern void softirq_init(void);
285 #define __raise_softirq_irqoff(nr) do { or_softirq_pending(1UL << (nr)); } while (0)
286 extern void raise_softirq_irqoff(unsigned int nr);
287 extern void raise_softirq(unsigned int nr);
289 /* This is the worklist that queues up per-cpu softirq work.
291 * send_remote_sendirq() adds work to these lists, and
292 * the softirq handler itself dequeues from them. The queues
293 * are protected by disabling local cpu interrupts and they must
294 * only be accessed by the local cpu that they are for.
296 DECLARE_PER_CPU(struct list_head [NR_SOFTIRQS], softirq_work_list);
298 /* Try to send a softirq to a remote cpu. If this cannot be done, the
299 * work will be queued to the local cpu.
301 extern void send_remote_softirq(struct call_single_data *cp, int cpu, int softirq);
303 /* Like send_remote_softirq(), but the caller must disable local cpu interrupts
304 * and compute the current cpu, passed in as 'this_cpu'.
306 extern void __send_remote_softirq(struct call_single_data *cp, int cpu,
307 int this_cpu, int softirq);
309 /* Tasklets --- multithreaded analogue of BHs.
311 Main feature differing them of generic softirqs: tasklet
312 is running only on one CPU simultaneously.
314 Main feature differing them of BHs: different tasklets
315 may be run simultaneously on different CPUs.
318 * If tasklet_schedule() is called, then tasklet is guaranteed
319 to be executed on some cpu at least once after this.
320 * If the tasklet is already scheduled, but its excecution is still not
321 started, it will be executed only once.
322 * If this tasklet is already running on another CPU (or schedule is called
323 from tasklet itself), it is rescheduled for later.
324 * Tasklet is strictly serialized wrt itself, but not
325 wrt another tasklets. If client needs some intertask synchronization,
326 he makes it with spinlocks.
329 struct tasklet_struct
331 struct tasklet_struct *next;
334 void (*func)(unsigned long);
338 #define DECLARE_TASKLET(name, func, data) \
339 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }
341 #define DECLARE_TASKLET_DISABLED(name, func, data) \
342 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
347 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
348 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
352 static inline int tasklet_trylock(struct tasklet_struct *t)
354 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
357 static inline void tasklet_unlock(struct tasklet_struct *t)
359 smp_mb__before_clear_bit();
360 clear_bit(TASKLET_STATE_RUN, &(t)->state);
363 static inline void tasklet_unlock_wait(struct tasklet_struct *t)
365 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
368 #define tasklet_trylock(t) 1
369 #define tasklet_unlock_wait(t) do { } while (0)
370 #define tasklet_unlock(t) do { } while (0)
373 extern void __tasklet_schedule(struct tasklet_struct *t);
375 static inline void tasklet_schedule(struct tasklet_struct *t)
377 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
378 __tasklet_schedule(t);
381 extern void __tasklet_hi_schedule(struct tasklet_struct *t);
383 static inline void tasklet_hi_schedule(struct tasklet_struct *t)
385 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
386 __tasklet_hi_schedule(t);
390 static inline void tasklet_disable_nosync(struct tasklet_struct *t)
392 atomic_inc(&t->count);
393 smp_mb__after_atomic_inc();
396 static inline void tasklet_disable(struct tasklet_struct *t)
398 tasklet_disable_nosync(t);
399 tasklet_unlock_wait(t);
403 static inline void tasklet_enable(struct tasklet_struct *t)
405 smp_mb__before_atomic_dec();
406 atomic_dec(&t->count);
409 static inline void tasklet_hi_enable(struct tasklet_struct *t)
411 smp_mb__before_atomic_dec();
412 atomic_dec(&t->count);
415 extern void tasklet_kill(struct tasklet_struct *t);
416 extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
417 extern void tasklet_init(struct tasklet_struct *t,
418 void (*func)(unsigned long), unsigned long data);
421 * Autoprobing for irqs:
423 * probe_irq_on() and probe_irq_off() provide robust primitives
424 * for accurate IRQ probing during kernel initialization. They are
425 * reasonably simple to use, are not "fooled" by spurious interrupts,
426 * and, unlike other attempts at IRQ probing, they do not get hung on
427 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
429 * For reasonably foolproof probing, use them as follows:
431 * 1. clear and/or mask the device's internal interrupt.
433 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs
434 * 4. enable the device and cause it to trigger an interrupt.
435 * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
436 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple
437 * 7. service the device to clear its pending interrupt.
438 * 8. loop again if paranoia is required.
440 * probe_irq_on() returns a mask of allocated irq's.
442 * probe_irq_off() takes the mask as a parameter,
443 * and returns the irq number which occurred,
444 * or zero if none occurred, or a negative irq number
445 * if more than one irq occurred.
448 #if defined(CONFIG_GENERIC_HARDIRQS) && !defined(CONFIG_GENERIC_IRQ_PROBE)
449 static inline unsigned long probe_irq_on(void)
453 static inline int probe_irq_off(unsigned long val)
457 static inline unsigned int probe_irq_mask(unsigned long val)
462 extern unsigned long probe_irq_on(void); /* returns 0 on failure */
463 extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */
464 extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */
467 #ifdef CONFIG_PROC_FS
468 /* Initialize /proc/irq/ */
469 extern void init_irq_proc(void);
471 static inline void init_irq_proc(void)
476 #if defined(CONFIG_GENERIC_HARDIRQS) && defined(CONFIG_DEBUG_SHIRQ)
477 extern void debug_poll_all_shared_irqs(void);
479 static inline void debug_poll_all_shared_irqs(void) { }
482 int show_interrupts(struct seq_file *p, void *v);
486 extern int early_irq_init(void);
487 extern int arch_probe_nr_irqs(void);
488 extern int arch_early_irq_init(void);
489 extern int arch_init_chip_data(struct irq_desc *desc, int cpu);