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/hardirq.h>
12 #include <linux/sched.h>
13 #include <linux/irqflags.h>
14 #include <asm/atomic.h>
15 #include <asm/ptrace.h>
16 #include <asm/system.h>
18 #ifndef CONFIG_GENERIC_HARDIRQS
19 # define for_each_irq_desc(irq, desc) \
20 for (irq = 0; irq < nr_irqs; irq++)
22 # define nr_irqs NR_IRQS
28 * These correspond to the IORESOURCE_IRQ_* defines in
29 * linux/ioport.h to select the interrupt line behaviour. When
30 * requesting an interrupt without specifying a IRQF_TRIGGER, the
31 * setting should be assumed to be "as already configured", which
32 * may be as per machine or firmware initialisation.
34 #define IRQF_TRIGGER_NONE 0x00000000
35 #define IRQF_TRIGGER_RISING 0x00000001
36 #define IRQF_TRIGGER_FALLING 0x00000002
37 #define IRQF_TRIGGER_HIGH 0x00000004
38 #define IRQF_TRIGGER_LOW 0x00000008
39 #define IRQF_TRIGGER_MASK (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \
40 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
41 #define IRQF_TRIGGER_PROBE 0x00000010
44 * These flags used only by the kernel as part of the
45 * irq handling routines.
47 * IRQF_DISABLED - keep irqs disabled when calling the action handler
48 * IRQF_SAMPLE_RANDOM - irq is used to feed the random generator
49 * IRQF_SHARED - allow sharing the irq among several devices
50 * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
51 * IRQF_TIMER - Flag to mark this interrupt as timer interrupt
52 * IRQF_PERCPU - Interrupt is per cpu
53 * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
54 * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
55 * registered first in an shared interrupt is considered for
56 * performance reasons)
58 #define IRQF_DISABLED 0x00000020
59 #define IRQF_SAMPLE_RANDOM 0x00000040
60 #define IRQF_SHARED 0x00000080
61 #define IRQF_PROBE_SHARED 0x00000100
62 #define IRQF_TIMER 0x00000200
63 #define IRQF_PERCPU 0x00000400
64 #define IRQF_NOBALANCING 0x00000800
65 #define IRQF_IRQPOLL 0x00001000
67 typedef irqreturn_t (*irq_handler_t)(int, void *);
70 irq_handler_t handler;
75 struct irqaction *next;
77 struct proc_dir_entry *dir;
80 extern irqreturn_t no_action(int cpl, void *dev_id);
81 extern int __must_check request_irq(unsigned int, irq_handler_t handler,
82 unsigned long, const char *, void *);
83 extern void free_irq(unsigned int, void *);
87 extern int __must_check devm_request_irq(struct device *dev, unsigned int irq,
88 irq_handler_t handler, unsigned long irqflags,
89 const char *devname, void *dev_id);
90 extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
93 * On lockdep we dont want to enable hardirqs in hardirq
94 * context. Use local_irq_enable_in_hardirq() to annotate
95 * kernel code that has to do this nevertheless (pretty much
96 * the only valid case is for old/broken hardware that is
99 * NOTE: in theory this might break fragile code that relies
100 * on hardirq delivery - in practice we dont seem to have such
101 * places left. So the only effect should be slightly increased
102 * irqs-off latencies.
104 #ifdef CONFIG_LOCKDEP
105 # define local_irq_enable_in_hardirq() do { } while (0)
107 # define local_irq_enable_in_hardirq() local_irq_enable()
110 extern void disable_irq_nosync(unsigned int irq);
111 extern void disable_irq(unsigned int irq);
112 extern void enable_irq(unsigned int irq);
114 #if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
116 extern cpumask_t irq_default_affinity;
118 extern int irq_set_affinity(unsigned int irq, cpumask_t cpumask);
119 extern int irq_can_set_affinity(unsigned int irq);
120 extern int irq_select_affinity(unsigned int irq);
122 #else /* CONFIG_SMP */
124 static inline int irq_set_affinity(unsigned int irq, cpumask_t cpumask)
129 static inline int irq_can_set_affinity(unsigned int irq)
134 static inline int irq_select_affinity(unsigned int irq) { return 0; }
136 #endif /* CONFIG_SMP && CONFIG_GENERIC_HARDIRQS */
138 #ifdef CONFIG_GENERIC_HARDIRQS
140 * Special lockdep variants of irq disabling/enabling.
141 * These should be used for locking constructs that
142 * know that a particular irq context which is disabled,
143 * and which is the only irq-context user of a lock,
144 * that it's safe to take the lock in the irq-disabled
145 * section without disabling hardirqs.
147 * On !CONFIG_LOCKDEP they are equivalent to the normal
148 * irq disable/enable methods.
150 static inline void disable_irq_nosync_lockdep(unsigned int irq)
152 disable_irq_nosync(irq);
153 #ifdef CONFIG_LOCKDEP
158 static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
160 disable_irq_nosync(irq);
161 #ifdef CONFIG_LOCKDEP
162 local_irq_save(*flags);
166 static inline void disable_irq_lockdep(unsigned int irq)
169 #ifdef CONFIG_LOCKDEP
174 static inline void enable_irq_lockdep(unsigned int irq)
176 #ifdef CONFIG_LOCKDEP
182 static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
184 #ifdef CONFIG_LOCKDEP
185 local_irq_restore(*flags);
190 /* IRQ wakeup (PM) control: */
191 extern int set_irq_wake(unsigned int irq, unsigned int on);
193 static inline int enable_irq_wake(unsigned int irq)
195 return set_irq_wake(irq, 1);
198 static inline int disable_irq_wake(unsigned int irq)
200 return set_irq_wake(irq, 0);
203 #else /* !CONFIG_GENERIC_HARDIRQS */
205 * NOTE: non-genirq architectures, if they want to support the lock
206 * validator need to define the methods below in their asm/irq.h
207 * files, under an #ifdef CONFIG_LOCKDEP section.
209 #ifndef CONFIG_LOCKDEP
210 # define disable_irq_nosync_lockdep(irq) disable_irq_nosync(irq)
211 # define disable_irq_nosync_lockdep_irqsave(irq, flags) \
212 disable_irq_nosync(irq)
213 # define disable_irq_lockdep(irq) disable_irq(irq)
214 # define enable_irq_lockdep(irq) enable_irq(irq)
215 # define enable_irq_lockdep_irqrestore(irq, flags) \
219 static inline int enable_irq_wake(unsigned int irq)
224 static inline int disable_irq_wake(unsigned int irq)
228 #endif /* CONFIG_GENERIC_HARDIRQS */
230 #ifndef __ARCH_SET_SOFTIRQ_PENDING
231 #define set_softirq_pending(x) (local_softirq_pending() = (x))
232 #define or_softirq_pending(x) (local_softirq_pending() |= (x))
235 /* Some architectures might implement lazy enabling/disabling of
236 * interrupts. In some cases, such as stop_machine, we might want
237 * to ensure that after a local_irq_disable(), interrupts have
238 * really been disabled in hardware. Such architectures need to
239 * implement the following hook.
241 #ifndef hard_irq_disable
242 #define hard_irq_disable() do { } while(0)
245 /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
246 frequency threaded job scheduling. For almost all the purposes
247 tasklets are more than enough. F.e. all serial device BHs et
248 al. should be converted to tasklets, not to softirqs.
260 #ifdef CONFIG_HIGH_RES_TIMERS
263 RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */
266 /* softirq mask and active fields moved to irq_cpustat_t in
267 * asm/hardirq.h to get better cache usage. KAO
270 struct softirq_action
272 void (*action)(struct softirq_action *);
275 asmlinkage void do_softirq(void);
276 asmlinkage void __do_softirq(void);
277 extern void open_softirq(int nr, void (*action)(struct softirq_action *));
278 extern void softirq_init(void);
279 #define __raise_softirq_irqoff(nr) do { or_softirq_pending(1UL << (nr)); } while (0)
280 extern void raise_softirq_irqoff(unsigned int nr);
281 extern void raise_softirq(unsigned int nr);
284 /* Tasklets --- multithreaded analogue of BHs.
286 Main feature differing them of generic softirqs: tasklet
287 is running only on one CPU simultaneously.
289 Main feature differing them of BHs: different tasklets
290 may be run simultaneously on different CPUs.
293 * If tasklet_schedule() is called, then tasklet is guaranteed
294 to be executed on some cpu at least once after this.
295 * If the tasklet is already scheduled, but its excecution is still not
296 started, it will be executed only once.
297 * If this tasklet is already running on another CPU (or schedule is called
298 from tasklet itself), it is rescheduled for later.
299 * Tasklet is strictly serialized wrt itself, but not
300 wrt another tasklets. If client needs some intertask synchronization,
301 he makes it with spinlocks.
304 struct tasklet_struct
306 struct tasklet_struct *next;
309 void (*func)(unsigned long);
313 #define DECLARE_TASKLET(name, func, data) \
314 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }
316 #define DECLARE_TASKLET_DISABLED(name, func, data) \
317 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
322 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
323 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
327 static inline int tasklet_trylock(struct tasklet_struct *t)
329 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
332 static inline void tasklet_unlock(struct tasklet_struct *t)
334 smp_mb__before_clear_bit();
335 clear_bit(TASKLET_STATE_RUN, &(t)->state);
338 static inline void tasklet_unlock_wait(struct tasklet_struct *t)
340 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
343 #define tasklet_trylock(t) 1
344 #define tasklet_unlock_wait(t) do { } while (0)
345 #define tasklet_unlock(t) do { } while (0)
348 extern void __tasklet_schedule(struct tasklet_struct *t);
350 static inline void tasklet_schedule(struct tasklet_struct *t)
352 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
353 __tasklet_schedule(t);
356 extern void __tasklet_hi_schedule(struct tasklet_struct *t);
358 static inline void tasklet_hi_schedule(struct tasklet_struct *t)
360 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
361 __tasklet_hi_schedule(t);
365 static inline void tasklet_disable_nosync(struct tasklet_struct *t)
367 atomic_inc(&t->count);
368 smp_mb__after_atomic_inc();
371 static inline void tasklet_disable(struct tasklet_struct *t)
373 tasklet_disable_nosync(t);
374 tasklet_unlock_wait(t);
378 static inline void tasklet_enable(struct tasklet_struct *t)
380 smp_mb__before_atomic_dec();
381 atomic_dec(&t->count);
384 static inline void tasklet_hi_enable(struct tasklet_struct *t)
386 smp_mb__before_atomic_dec();
387 atomic_dec(&t->count);
390 extern void tasklet_kill(struct tasklet_struct *t);
391 extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
392 extern void tasklet_init(struct tasklet_struct *t,
393 void (*func)(unsigned long), unsigned long data);
396 * Autoprobing for irqs:
398 * probe_irq_on() and probe_irq_off() provide robust primitives
399 * for accurate IRQ probing during kernel initialization. They are
400 * reasonably simple to use, are not "fooled" by spurious interrupts,
401 * and, unlike other attempts at IRQ probing, they do not get hung on
402 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
404 * For reasonably foolproof probing, use them as follows:
406 * 1. clear and/or mask the device's internal interrupt.
408 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs
409 * 4. enable the device and cause it to trigger an interrupt.
410 * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
411 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple
412 * 7. service the device to clear its pending interrupt.
413 * 8. loop again if paranoia is required.
415 * probe_irq_on() returns a mask of allocated irq's.
417 * probe_irq_off() takes the mask as a parameter,
418 * and returns the irq number which occurred,
419 * or zero if none occurred, or a negative irq number
420 * if more than one irq occurred.
423 #if defined(CONFIG_GENERIC_HARDIRQS) && !defined(CONFIG_GENERIC_IRQ_PROBE)
424 static inline unsigned long probe_irq_on(void)
428 static inline int probe_irq_off(unsigned long val)
432 static inline unsigned int probe_irq_mask(unsigned long val)
437 extern unsigned long probe_irq_on(void); /* returns 0 on failure */
438 extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */
439 extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */
442 #ifdef CONFIG_PROC_FS
443 /* Initialize /proc/irq/ */
444 extern void init_irq_proc(void);
446 static inline void init_irq_proc(void)
451 int show_interrupts(struct seq_file *p, void *v);