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>
20 #ifndef CONFIG_GENERIC_HARDIRQS
21 #define for_each_irq_desc(irq, desc) \
22 for (irq = 0; irq < nr_irqs; irq++)
26 * These correspond to the IORESOURCE_IRQ_* defines in
27 * linux/ioport.h to select the interrupt line behaviour. When
28 * requesting an interrupt without specifying a IRQF_TRIGGER, the
29 * setting should be assumed to be "as already configured", which
30 * may be as per machine or firmware initialisation.
32 #define IRQF_TRIGGER_NONE 0x00000000
33 #define IRQF_TRIGGER_RISING 0x00000001
34 #define IRQF_TRIGGER_FALLING 0x00000002
35 #define IRQF_TRIGGER_HIGH 0x00000004
36 #define IRQF_TRIGGER_LOW 0x00000008
37 #define IRQF_TRIGGER_MASK (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \
38 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
39 #define IRQF_TRIGGER_PROBE 0x00000010
42 * These flags used only by the kernel as part of the
43 * irq handling routines.
45 * IRQF_DISABLED - keep irqs disabled when calling the action handler
46 * IRQF_SAMPLE_RANDOM - irq is used to feed the random generator
47 * IRQF_SHARED - allow sharing the irq among several devices
48 * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
49 * IRQF_TIMER - Flag to mark this interrupt as timer interrupt
50 * IRQF_PERCPU - Interrupt is per cpu
51 * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
52 * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
53 * registered first in an shared interrupt is considered for
54 * performance reasons)
56 #define IRQF_DISABLED 0x00000020
57 #define IRQF_SAMPLE_RANDOM 0x00000040
58 #define IRQF_SHARED 0x00000080
59 #define IRQF_PROBE_SHARED 0x00000100
60 #define IRQF_TIMER 0x00000200
61 #define IRQF_PERCPU 0x00000400
62 #define IRQF_NOBALANCING 0x00000800
63 #define IRQF_IRQPOLL 0x00001000
65 typedef irqreturn_t (*irq_handler_t)(int, void *);
68 irq_handler_t handler;
73 struct irqaction *next;
75 struct proc_dir_entry *dir;
78 extern irqreturn_t no_action(int cpl, void *dev_id);
79 extern int __must_check request_irq(unsigned int, irq_handler_t handler,
80 unsigned long, const char *, void *);
81 extern void free_irq(unsigned int, void *);
85 extern int __must_check devm_request_irq(struct device *dev, unsigned int irq,
86 irq_handler_t handler, unsigned long irqflags,
87 const char *devname, void *dev_id);
88 extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
91 * On lockdep we dont want to enable hardirqs in hardirq
92 * context. Use local_irq_enable_in_hardirq() to annotate
93 * kernel code that has to do this nevertheless (pretty much
94 * the only valid case is for old/broken hardware that is
97 * NOTE: in theory this might break fragile code that relies
98 * on hardirq delivery - in practice we dont seem to have such
99 * places left. So the only effect should be slightly increased
100 * irqs-off latencies.
102 #ifdef CONFIG_LOCKDEP
103 # define local_irq_enable_in_hardirq() do { } while (0)
105 # define local_irq_enable_in_hardirq() local_irq_enable()
108 extern void disable_irq_nosync(unsigned int irq);
109 extern void disable_irq(unsigned int irq);
110 extern void enable_irq(unsigned int irq);
112 #if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
114 extern cpumask_t irq_default_affinity;
116 extern int irq_set_affinity(unsigned int irq, cpumask_t cpumask);
117 extern int irq_can_set_affinity(unsigned int irq);
118 extern int irq_select_affinity(unsigned int irq);
120 #else /* CONFIG_SMP */
122 static inline int irq_set_affinity(unsigned int irq, cpumask_t cpumask)
127 static inline int irq_can_set_affinity(unsigned int irq)
132 static inline int irq_select_affinity(unsigned int irq) { return 0; }
134 #endif /* CONFIG_SMP && CONFIG_GENERIC_HARDIRQS */
136 #ifdef CONFIG_GENERIC_HARDIRQS
138 * Special lockdep variants of irq disabling/enabling.
139 * These should be used for locking constructs that
140 * know that a particular irq context which is disabled,
141 * and which is the only irq-context user of a lock,
142 * that it's safe to take the lock in the irq-disabled
143 * section without disabling hardirqs.
145 * On !CONFIG_LOCKDEP they are equivalent to the normal
146 * irq disable/enable methods.
148 static inline void disable_irq_nosync_lockdep(unsigned int irq)
150 disable_irq_nosync(irq);
151 #ifdef CONFIG_LOCKDEP
156 static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
158 disable_irq_nosync(irq);
159 #ifdef CONFIG_LOCKDEP
160 local_irq_save(*flags);
164 static inline void disable_irq_lockdep(unsigned int irq)
167 #ifdef CONFIG_LOCKDEP
172 static inline void enable_irq_lockdep(unsigned int irq)
174 #ifdef CONFIG_LOCKDEP
180 static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
182 #ifdef CONFIG_LOCKDEP
183 local_irq_restore(*flags);
188 /* IRQ wakeup (PM) control: */
189 extern int set_irq_wake(unsigned int irq, unsigned int on);
191 static inline int enable_irq_wake(unsigned int irq)
193 return set_irq_wake(irq, 1);
196 static inline int disable_irq_wake(unsigned int irq)
198 return set_irq_wake(irq, 0);
201 #else /* !CONFIG_GENERIC_HARDIRQS */
203 * NOTE: non-genirq architectures, if they want to support the lock
204 * validator need to define the methods below in their asm/irq.h
205 * files, under an #ifdef CONFIG_LOCKDEP section.
207 #ifndef CONFIG_LOCKDEP
208 # define disable_irq_nosync_lockdep(irq) disable_irq_nosync(irq)
209 # define disable_irq_nosync_lockdep_irqsave(irq, flags) \
210 disable_irq_nosync(irq)
211 # define disable_irq_lockdep(irq) disable_irq(irq)
212 # define enable_irq_lockdep(irq) enable_irq(irq)
213 # define enable_irq_lockdep_irqrestore(irq, flags) \
217 static inline int enable_irq_wake(unsigned int irq)
222 static inline int disable_irq_wake(unsigned int irq)
226 #endif /* CONFIG_GENERIC_HARDIRQS */
228 #ifndef __ARCH_SET_SOFTIRQ_PENDING
229 #define set_softirq_pending(x) (local_softirq_pending() = (x))
230 #define or_softirq_pending(x) (local_softirq_pending() |= (x))
233 /* Some architectures might implement lazy enabling/disabling of
234 * interrupts. In some cases, such as stop_machine, we might want
235 * to ensure that after a local_irq_disable(), interrupts have
236 * really been disabled in hardware. Such architectures need to
237 * implement the following hook.
239 #ifndef hard_irq_disable
240 #define hard_irq_disable() do { } while(0)
243 /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
244 frequency threaded job scheduling. For almost all the purposes
245 tasklets are more than enough. F.e. all serial device BHs et
246 al. should be converted to tasklets, not to softirqs.
258 #ifdef CONFIG_HIGH_RES_TIMERS
261 RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */
264 /* softirq mask and active fields moved to irq_cpustat_t in
265 * asm/hardirq.h to get better cache usage. KAO
268 struct softirq_action
270 void (*action)(struct softirq_action *);
273 asmlinkage void do_softirq(void);
274 asmlinkage void __do_softirq(void);
275 extern void open_softirq(int nr, void (*action)(struct softirq_action *));
276 extern void softirq_init(void);
277 #define __raise_softirq_irqoff(nr) do { or_softirq_pending(1UL << (nr)); } while (0)
278 extern void raise_softirq_irqoff(unsigned int nr);
279 extern void raise_softirq(unsigned int nr);
282 /* Tasklets --- multithreaded analogue of BHs.
284 Main feature differing them of generic softirqs: tasklet
285 is running only on one CPU simultaneously.
287 Main feature differing them of BHs: different tasklets
288 may be run simultaneously on different CPUs.
291 * If tasklet_schedule() is called, then tasklet is guaranteed
292 to be executed on some cpu at least once after this.
293 * If the tasklet is already scheduled, but its excecution is still not
294 started, it will be executed only once.
295 * If this tasklet is already running on another CPU (or schedule is called
296 from tasklet itself), it is rescheduled for later.
297 * Tasklet is strictly serialized wrt itself, but not
298 wrt another tasklets. If client needs some intertask synchronization,
299 he makes it with spinlocks.
302 struct tasklet_struct
304 struct tasklet_struct *next;
307 void (*func)(unsigned long);
311 #define DECLARE_TASKLET(name, func, data) \
312 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }
314 #define DECLARE_TASKLET_DISABLED(name, func, data) \
315 struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
320 TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
321 TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
325 static inline int tasklet_trylock(struct tasklet_struct *t)
327 return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
330 static inline void tasklet_unlock(struct tasklet_struct *t)
332 smp_mb__before_clear_bit();
333 clear_bit(TASKLET_STATE_RUN, &(t)->state);
336 static inline void tasklet_unlock_wait(struct tasklet_struct *t)
338 while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); }
341 #define tasklet_trylock(t) 1
342 #define tasklet_unlock_wait(t) do { } while (0)
343 #define tasklet_unlock(t) do { } while (0)
346 extern void __tasklet_schedule(struct tasklet_struct *t);
348 static inline void tasklet_schedule(struct tasklet_struct *t)
350 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
351 __tasklet_schedule(t);
354 extern void __tasklet_hi_schedule(struct tasklet_struct *t);
356 static inline void tasklet_hi_schedule(struct tasklet_struct *t)
358 if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
359 __tasklet_hi_schedule(t);
363 static inline void tasklet_disable_nosync(struct tasklet_struct *t)
365 atomic_inc(&t->count);
366 smp_mb__after_atomic_inc();
369 static inline void tasklet_disable(struct tasklet_struct *t)
371 tasklet_disable_nosync(t);
372 tasklet_unlock_wait(t);
376 static inline void tasklet_enable(struct tasklet_struct *t)
378 smp_mb__before_atomic_dec();
379 atomic_dec(&t->count);
382 static inline void tasklet_hi_enable(struct tasklet_struct *t)
384 smp_mb__before_atomic_dec();
385 atomic_dec(&t->count);
388 extern void tasklet_kill(struct tasklet_struct *t);
389 extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
390 extern void tasklet_init(struct tasklet_struct *t,
391 void (*func)(unsigned long), unsigned long data);
394 * Autoprobing for irqs:
396 * probe_irq_on() and probe_irq_off() provide robust primitives
397 * for accurate IRQ probing during kernel initialization. They are
398 * reasonably simple to use, are not "fooled" by spurious interrupts,
399 * and, unlike other attempts at IRQ probing, they do not get hung on
400 * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
402 * For reasonably foolproof probing, use them as follows:
404 * 1. clear and/or mask the device's internal interrupt.
406 * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs
407 * 4. enable the device and cause it to trigger an interrupt.
408 * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
409 * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple
410 * 7. service the device to clear its pending interrupt.
411 * 8. loop again if paranoia is required.
413 * probe_irq_on() returns a mask of allocated irq's.
415 * probe_irq_off() takes the mask as a parameter,
416 * and returns the irq number which occurred,
417 * or zero if none occurred, or a negative irq number
418 * if more than one irq occurred.
421 #if defined(CONFIG_GENERIC_HARDIRQS) && !defined(CONFIG_GENERIC_IRQ_PROBE)
422 static inline unsigned long probe_irq_on(void)
426 static inline int probe_irq_off(unsigned long val)
430 static inline unsigned int probe_irq_mask(unsigned long val)
435 extern unsigned long probe_irq_on(void); /* returns 0 on failure */
436 extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */
437 extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */
440 #ifdef CONFIG_PROC_FS
441 /* Initialize /proc/irq/ */
442 extern void init_irq_proc(void);
444 static inline void init_irq_proc(void)
449 int show_interrupts(struct seq_file *p, void *v);