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-rw-r--r--kernel/include/linux/interrupt.h695
1 files changed, 695 insertions, 0 deletions
diff --git a/kernel/include/linux/interrupt.h b/kernel/include/linux/interrupt.h
new file mode 100644
index 000000000..67f2af8c0
--- /dev/null
+++ b/kernel/include/linux/interrupt.h
@@ -0,0 +1,695 @@
+/* interrupt.h */
+#ifndef _LINUX_INTERRUPT_H
+#define _LINUX_INTERRUPT_H
+
+#include <linux/kernel.h>
+#include <linux/linkage.h>
+#include <linux/bitops.h>
+#include <linux/preempt.h>
+#include <linux/cpumask.h>
+#include <linux/irqreturn.h>
+#include <linux/irqnr.h>
+#include <linux/hardirq.h>
+#include <linux/irqflags.h>
+#include <linux/hrtimer.h>
+#include <linux/kref.h>
+#include <linux/workqueue.h>
+
+#include <linux/atomic.h>
+#include <asm/ptrace.h>
+#include <asm/irq.h>
+
+/*
+ * These correspond to the IORESOURCE_IRQ_* defines in
+ * linux/ioport.h to select the interrupt line behaviour. When
+ * requesting an interrupt without specifying a IRQF_TRIGGER, the
+ * setting should be assumed to be "as already configured", which
+ * may be as per machine or firmware initialisation.
+ */
+#define IRQF_TRIGGER_NONE 0x00000000
+#define IRQF_TRIGGER_RISING 0x00000001
+#define IRQF_TRIGGER_FALLING 0x00000002
+#define IRQF_TRIGGER_HIGH 0x00000004
+#define IRQF_TRIGGER_LOW 0x00000008
+#define IRQF_TRIGGER_MASK (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \
+ IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
+#define IRQF_TRIGGER_PROBE 0x00000010
+
+/*
+ * These flags used only by the kernel as part of the
+ * irq handling routines.
+ *
+ * IRQF_SHARED - allow sharing the irq among several devices
+ * IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
+ * IRQF_TIMER - Flag to mark this interrupt as timer interrupt
+ * IRQF_PERCPU - Interrupt is per cpu
+ * IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
+ * IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
+ * registered first in an shared interrupt is considered for
+ * performance reasons)
+ * IRQF_ONESHOT - Interrupt is not reenabled after the hardirq handler finished.
+ * Used by threaded interrupts which need to keep the
+ * irq line disabled until the threaded handler has been run.
+ * IRQF_NO_SUSPEND - Do not disable this IRQ during suspend. Does not guarantee
+ * that this interrupt will wake the system from a suspended
+ * state. See Documentation/power/suspend-and-interrupts.txt
+ * IRQF_FORCE_RESUME - Force enable it on resume even if IRQF_NO_SUSPEND is set
+ * IRQF_NO_THREAD - Interrupt cannot be threaded
+ * IRQF_EARLY_RESUME - Resume IRQ early during syscore instead of at device
+ * resume time.
+ * IRQF_COND_SUSPEND - If the IRQ is shared with a NO_SUSPEND user, execute this
+ * interrupt handler after suspending interrupts. For system
+ * wakeup devices users need to implement wakeup detection in
+ * their interrupt handlers.
+ * IRQF_NO_SOFTIRQ_CALL - Do not process softirqs in the irq thread context (RT)
+ */
+#define IRQF_SHARED 0x00000080
+#define IRQF_PROBE_SHARED 0x00000100
+#define __IRQF_TIMER 0x00000200
+#define IRQF_PERCPU 0x00000400
+#define IRQF_NOBALANCING 0x00000800
+#define IRQF_IRQPOLL 0x00001000
+#define IRQF_ONESHOT 0x00002000
+#define IRQF_NO_SUSPEND 0x00004000
+#define IRQF_FORCE_RESUME 0x00008000
+#define IRQF_NO_THREAD 0x00010000
+#define IRQF_EARLY_RESUME 0x00020000
+#define IRQF_COND_SUSPEND 0x00040000
+#define IRQF_NO_SOFTIRQ_CALL 0x00080000
+
+#define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD)
+
+/*
+ * These values can be returned by request_any_context_irq() and
+ * describe the context the interrupt will be run in.
+ *
+ * IRQC_IS_HARDIRQ - interrupt runs in hardirq context
+ * IRQC_IS_NESTED - interrupt runs in a nested threaded context
+ */
+enum {
+ IRQC_IS_HARDIRQ = 0,
+ IRQC_IS_NESTED,
+};
+
+typedef irqreturn_t (*irq_handler_t)(int, void *);
+
+/**
+ * struct irqaction - per interrupt action descriptor
+ * @handler: interrupt handler function
+ * @name: name of the device
+ * @dev_id: cookie to identify the device
+ * @percpu_dev_id: cookie to identify the device
+ * @next: pointer to the next irqaction for shared interrupts
+ * @irq: interrupt number
+ * @flags: flags (see IRQF_* above)
+ * @thread_fn: interrupt handler function for threaded interrupts
+ * @thread: thread pointer for threaded interrupts
+ * @thread_flags: flags related to @thread
+ * @thread_mask: bitmask for keeping track of @thread activity
+ * @dir: pointer to the proc/irq/NN/name entry
+ */
+struct irqaction {
+ irq_handler_t handler;
+ void *dev_id;
+ void __percpu *percpu_dev_id;
+ struct irqaction *next;
+ irq_handler_t thread_fn;
+ struct task_struct *thread;
+ unsigned int irq;
+ unsigned int flags;
+ unsigned long thread_flags;
+ unsigned long thread_mask;
+ const char *name;
+ struct proc_dir_entry *dir;
+} ____cacheline_internodealigned_in_smp;
+
+extern irqreturn_t no_action(int cpl, void *dev_id);
+
+extern int __must_check
+request_threaded_irq(unsigned int irq, irq_handler_t handler,
+ irq_handler_t thread_fn,
+ unsigned long flags, const char *name, void *dev);
+
+static inline int __must_check
+request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
+ const char *name, void *dev)
+{
+ return request_threaded_irq(irq, handler, NULL, flags, name, dev);
+}
+
+extern int __must_check
+request_any_context_irq(unsigned int irq, irq_handler_t handler,
+ unsigned long flags, const char *name, void *dev_id);
+
+extern int __must_check
+request_percpu_irq(unsigned int irq, irq_handler_t handler,
+ const char *devname, void __percpu *percpu_dev_id);
+
+extern void free_irq(unsigned int, void *);
+extern void free_percpu_irq(unsigned int, void __percpu *);
+
+struct device;
+
+extern int __must_check
+devm_request_threaded_irq(struct device *dev, unsigned int irq,
+ irq_handler_t handler, irq_handler_t thread_fn,
+ unsigned long irqflags, const char *devname,
+ void *dev_id);
+
+static inline int __must_check
+devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler,
+ unsigned long irqflags, const char *devname, void *dev_id)
+{
+ return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags,
+ devname, dev_id);
+}
+
+extern int __must_check
+devm_request_any_context_irq(struct device *dev, unsigned int irq,
+ irq_handler_t handler, unsigned long irqflags,
+ const char *devname, void *dev_id);
+
+extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
+
+/*
+ * On lockdep we dont want to enable hardirqs in hardirq
+ * context. Use local_irq_enable_in_hardirq() to annotate
+ * kernel code that has to do this nevertheless (pretty much
+ * the only valid case is for old/broken hardware that is
+ * insanely slow).
+ *
+ * NOTE: in theory this might break fragile code that relies
+ * on hardirq delivery - in practice we dont seem to have such
+ * places left. So the only effect should be slightly increased
+ * irqs-off latencies.
+ */
+#ifdef CONFIG_LOCKDEP
+# define local_irq_enable_in_hardirq() do { } while (0)
+#else
+# define local_irq_enable_in_hardirq() local_irq_enable_nort()
+#endif
+
+extern void disable_irq_nosync(unsigned int irq);
+extern bool disable_hardirq(unsigned int irq);
+extern void disable_irq(unsigned int irq);
+extern void disable_percpu_irq(unsigned int irq);
+extern void enable_irq(unsigned int irq);
+extern void enable_percpu_irq(unsigned int irq, unsigned int type);
+extern void irq_wake_thread(unsigned int irq, void *dev_id);
+
+/* The following three functions are for the core kernel use only. */
+extern void suspend_device_irqs(void);
+extern void resume_device_irqs(void);
+
+/**
+ * struct irq_affinity_notify - context for notification of IRQ affinity changes
+ * @irq: Interrupt to which notification applies
+ * @kref: Reference count, for internal use
+ * @work: Work item, for internal use
+ * @notify: Function to be called on change. This will be
+ * called in process context.
+ * @release: Function to be called on release. This will be
+ * called in process context. Once registered, the
+ * structure must only be freed when this function is
+ * called or later.
+ */
+struct irq_affinity_notify {
+ unsigned int irq;
+ struct kref kref;
+ struct work_struct work;
+ struct list_head list;
+ void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask);
+ void (*release)(struct kref *ref);
+};
+
+#if defined(CONFIG_SMP)
+
+extern cpumask_var_t irq_default_affinity;
+
+/* Internal implementation. Use the helpers below */
+extern int __irq_set_affinity(unsigned int irq, const struct cpumask *cpumask,
+ bool force);
+
+/**
+ * irq_set_affinity - Set the irq affinity of a given irq
+ * @irq: Interrupt to set affinity
+ * @cpumask: cpumask
+ *
+ * Fails if cpumask does not contain an online CPU
+ */
+static inline int
+irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
+{
+ return __irq_set_affinity(irq, cpumask, false);
+}
+
+/**
+ * irq_force_affinity - Force the irq affinity of a given irq
+ * @irq: Interrupt to set affinity
+ * @cpumask: cpumask
+ *
+ * Same as irq_set_affinity, but without checking the mask against
+ * online cpus.
+ *
+ * Solely for low level cpu hotplug code, where we need to make per
+ * cpu interrupts affine before the cpu becomes online.
+ */
+static inline int
+irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
+{
+ return __irq_set_affinity(irq, cpumask, true);
+}
+
+extern int irq_can_set_affinity(unsigned int irq);
+extern int irq_select_affinity(unsigned int irq);
+
+extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m);
+
+extern int
+irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);
+
+#else /* CONFIG_SMP */
+
+static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
+{
+ return -EINVAL;
+}
+
+static inline int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
+{
+ return 0;
+}
+
+static inline int irq_can_set_affinity(unsigned int irq)
+{
+ return 0;
+}
+
+static inline int irq_select_affinity(unsigned int irq) { return 0; }
+
+static inline int irq_set_affinity_hint(unsigned int irq,
+ const struct cpumask *m)
+{
+ return -EINVAL;
+}
+
+static inline int
+irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
+{
+ return 0;
+}
+#endif /* CONFIG_SMP */
+
+/*
+ * Special lockdep variants of irq disabling/enabling.
+ * These should be used for locking constructs that
+ * know that a particular irq context which is disabled,
+ * and which is the only irq-context user of a lock,
+ * that it's safe to take the lock in the irq-disabled
+ * section without disabling hardirqs.
+ *
+ * On !CONFIG_LOCKDEP they are equivalent to the normal
+ * irq disable/enable methods.
+ */
+static inline void disable_irq_nosync_lockdep(unsigned int irq)
+{
+ disable_irq_nosync(irq);
+#ifdef CONFIG_LOCKDEP
+ local_irq_disable();
+#endif
+}
+
+static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
+{
+ disable_irq_nosync(irq);
+#ifdef CONFIG_LOCKDEP
+ local_irq_save(*flags);
+#endif
+}
+
+static inline void disable_irq_lockdep(unsigned int irq)
+{
+ disable_irq(irq);
+#ifdef CONFIG_LOCKDEP
+ local_irq_disable();
+#endif
+}
+
+static inline void enable_irq_lockdep(unsigned int irq)
+{
+#ifdef CONFIG_LOCKDEP
+ local_irq_enable();
+#endif
+ enable_irq(irq);
+}
+
+static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
+{
+#ifdef CONFIG_LOCKDEP
+ local_irq_restore(*flags);
+#endif
+ enable_irq(irq);
+}
+
+/* IRQ wakeup (PM) control: */
+extern int irq_set_irq_wake(unsigned int irq, unsigned int on);
+
+static inline int enable_irq_wake(unsigned int irq)
+{
+ return irq_set_irq_wake(irq, 1);
+}
+
+static inline int disable_irq_wake(unsigned int irq)
+{
+ return irq_set_irq_wake(irq, 0);
+}
+
+/*
+ * irq_get_irqchip_state/irq_set_irqchip_state specific flags
+ */
+enum irqchip_irq_state {
+ IRQCHIP_STATE_PENDING, /* Is interrupt pending? */
+ IRQCHIP_STATE_ACTIVE, /* Is interrupt in progress? */
+ IRQCHIP_STATE_MASKED, /* Is interrupt masked? */
+ IRQCHIP_STATE_LINE_LEVEL, /* Is IRQ line high? */
+};
+
+extern int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
+ bool *state);
+extern int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
+ bool state);
+
+#ifdef CONFIG_IRQ_FORCED_THREADING
+# ifndef CONFIG_PREEMPT_RT_BASE
+extern bool force_irqthreads;
+# else
+# define force_irqthreads (true)
+# endif
+#else
+#define force_irqthreads (false)
+#endif
+
+#ifndef __ARCH_SET_SOFTIRQ_PENDING
+#define set_softirq_pending(x) (local_softirq_pending() = (x))
+#define or_softirq_pending(x) (local_softirq_pending() |= (x))
+#endif
+
+/* Some architectures might implement lazy enabling/disabling of
+ * interrupts. In some cases, such as stop_machine, we might want
+ * to ensure that after a local_irq_disable(), interrupts have
+ * really been disabled in hardware. Such architectures need to
+ * implement the following hook.
+ */
+#ifndef hard_irq_disable
+#define hard_irq_disable() do { } while(0)
+#endif
+
+/* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
+ frequency threaded job scheduling. For almost all the purposes
+ tasklets are more than enough. F.e. all serial device BHs et
+ al. should be converted to tasklets, not to softirqs.
+ */
+
+enum
+{
+ HI_SOFTIRQ=0,
+ TIMER_SOFTIRQ,
+ NET_TX_SOFTIRQ,
+ NET_RX_SOFTIRQ,
+ BLOCK_SOFTIRQ,
+ BLOCK_IOPOLL_SOFTIRQ,
+ TASKLET_SOFTIRQ,
+ SCHED_SOFTIRQ,
+ HRTIMER_SOFTIRQ,
+ RCU_SOFTIRQ, /* Preferable RCU should always be the last softirq */
+
+ NR_SOFTIRQS
+};
+
+#define SOFTIRQ_STOP_IDLE_MASK (~(1 << RCU_SOFTIRQ))
+
+/* map softirq index to softirq name. update 'softirq_to_name' in
+ * kernel/softirq.c when adding a new softirq.
+ */
+extern const char * const softirq_to_name[NR_SOFTIRQS];
+
+/* softirq mask and active fields moved to irq_cpustat_t in
+ * asm/hardirq.h to get better cache usage. KAO
+ */
+
+struct softirq_action
+{
+ void (*action)(struct softirq_action *);
+};
+
+#ifndef CONFIG_PREEMPT_RT_FULL
+asmlinkage void do_softirq(void);
+asmlinkage void __do_softirq(void);
+static inline void thread_do_softirq(void) { do_softirq(); }
+#ifdef __ARCH_HAS_DO_SOFTIRQ
+void do_softirq_own_stack(void);
+#else
+static inline void do_softirq_own_stack(void)
+{
+ __do_softirq();
+}
+#endif
+#else
+extern void thread_do_softirq(void);
+#endif
+
+extern void open_softirq(int nr, void (*action)(struct softirq_action *));
+extern void softirq_init(void);
+extern void __raise_softirq_irqoff(unsigned int nr);
+
+extern void raise_softirq_irqoff(unsigned int nr);
+extern void raise_softirq(unsigned int nr);
+extern void softirq_check_pending_idle(void);
+
+DECLARE_PER_CPU(struct task_struct *, ksoftirqd);
+
+static inline struct task_struct *this_cpu_ksoftirqd(void)
+{
+ return this_cpu_read(ksoftirqd);
+}
+
+/* Tasklets --- multithreaded analogue of BHs.
+
+ Main feature differing them of generic softirqs: tasklet
+ is running only on one CPU simultaneously.
+
+ Main feature differing them of BHs: different tasklets
+ may be run simultaneously on different CPUs.
+
+ Properties:
+ * If tasklet_schedule() is called, then tasklet is guaranteed
+ to be executed on some cpu at least once after this.
+ * If the tasklet is already scheduled, but its execution is still not
+ started, it will be executed only once.
+ * If this tasklet is already running on another CPU, it is rescheduled
+ for later.
+ * Schedule must not be called from the tasklet itself (a lockup occurs)
+ * Tasklet is strictly serialized wrt itself, but not
+ wrt another tasklets. If client needs some intertask synchronization,
+ he makes it with spinlocks.
+ */
+
+struct tasklet_struct
+{
+ struct tasklet_struct *next;
+ unsigned long state;
+ atomic_t count;
+ void (*func)(unsigned long);
+ unsigned long data;
+};
+
+#define DECLARE_TASKLET(name, func, data) \
+struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(0), func, data }
+
+#define DECLARE_TASKLET_DISABLED(name, func, data) \
+struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data }
+
+
+enum
+{
+ TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
+ TASKLET_STATE_RUN, /* Tasklet is running (SMP only) */
+ TASKLET_STATE_PENDING /* Tasklet is pending */
+};
+
+#define TASKLET_STATEF_SCHED (1 << TASKLET_STATE_SCHED)
+#define TASKLET_STATEF_RUN (1 << TASKLET_STATE_RUN)
+#define TASKLET_STATEF_PENDING (1 << TASKLET_STATE_PENDING)
+
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL)
+static inline int tasklet_trylock(struct tasklet_struct *t)
+{
+ return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
+}
+
+static inline int tasklet_tryunlock(struct tasklet_struct *t)
+{
+ return cmpxchg(&t->state, TASKLET_STATEF_RUN, 0) == TASKLET_STATEF_RUN;
+}
+
+static inline void tasklet_unlock(struct tasklet_struct *t)
+{
+ smp_mb__before_atomic();
+ clear_bit(TASKLET_STATE_RUN, &(t)->state);
+}
+
+extern void tasklet_unlock_wait(struct tasklet_struct *t);
+
+#else
+#define tasklet_trylock(t) 1
+#define tasklet_tryunlock(t) 1
+#define tasklet_unlock_wait(t) do { } while (0)
+#define tasklet_unlock(t) do { } while (0)
+#endif
+
+extern void __tasklet_schedule(struct tasklet_struct *t);
+
+static inline void tasklet_schedule(struct tasklet_struct *t)
+{
+ if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
+ __tasklet_schedule(t);
+}
+
+extern void __tasklet_hi_schedule(struct tasklet_struct *t);
+
+static inline void tasklet_hi_schedule(struct tasklet_struct *t)
+{
+ if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
+ __tasklet_hi_schedule(t);
+}
+
+extern void __tasklet_hi_schedule_first(struct tasklet_struct *t);
+
+/*
+ * This version avoids touching any other tasklets. Needed for kmemcheck
+ * in order not to take any page faults while enqueueing this tasklet;
+ * consider VERY carefully whether you really need this or
+ * tasklet_hi_schedule()...
+ */
+static inline void tasklet_hi_schedule_first(struct tasklet_struct *t)
+{
+ if (!test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
+ __tasklet_hi_schedule_first(t);
+}
+
+
+static inline void tasklet_disable_nosync(struct tasklet_struct *t)
+{
+ atomic_inc(&t->count);
+ smp_mb__after_atomic();
+}
+
+static inline void tasklet_disable(struct tasklet_struct *t)
+{
+ tasklet_disable_nosync(t);
+ tasklet_unlock_wait(t);
+ smp_mb();
+}
+
+extern void tasklet_enable(struct tasklet_struct *t);
+extern void tasklet_kill(struct tasklet_struct *t);
+extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu);
+extern void tasklet_init(struct tasklet_struct *t,
+ void (*func)(unsigned long), unsigned long data);
+
+struct tasklet_hrtimer {
+ struct hrtimer timer;
+ struct tasklet_struct tasklet;
+ enum hrtimer_restart (*function)(struct hrtimer *);
+};
+
+extern void
+tasklet_hrtimer_init(struct tasklet_hrtimer *ttimer,
+ enum hrtimer_restart (*function)(struct hrtimer *),
+ clockid_t which_clock, enum hrtimer_mode mode);
+
+static inline
+int tasklet_hrtimer_start(struct tasklet_hrtimer *ttimer, ktime_t time,
+ const enum hrtimer_mode mode)
+{
+ return hrtimer_start(&ttimer->timer, time, mode);
+}
+
+static inline
+void tasklet_hrtimer_cancel(struct tasklet_hrtimer *ttimer)
+{
+ hrtimer_cancel(&ttimer->timer);
+ tasklet_kill(&ttimer->tasklet);
+}
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+extern void softirq_early_init(void);
+#else
+static inline void softirq_early_init(void) { }
+#endif
+
+/*
+ * Autoprobing for irqs:
+ *
+ * probe_irq_on() and probe_irq_off() provide robust primitives
+ * for accurate IRQ probing during kernel initialization. They are
+ * reasonably simple to use, are not "fooled" by spurious interrupts,
+ * and, unlike other attempts at IRQ probing, they do not get hung on
+ * stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
+ *
+ * For reasonably foolproof probing, use them as follows:
+ *
+ * 1. clear and/or mask the device's internal interrupt.
+ * 2. sti();
+ * 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs
+ * 4. enable the device and cause it to trigger an interrupt.
+ * 5. wait for the device to interrupt, using non-intrusive polling or a delay.
+ * 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple
+ * 7. service the device to clear its pending interrupt.
+ * 8. loop again if paranoia is required.
+ *
+ * probe_irq_on() returns a mask of allocated irq's.
+ *
+ * probe_irq_off() takes the mask as a parameter,
+ * and returns the irq number which occurred,
+ * or zero if none occurred, or a negative irq number
+ * if more than one irq occurred.
+ */
+
+#if !defined(CONFIG_GENERIC_IRQ_PROBE)
+static inline unsigned long probe_irq_on(void)
+{
+ return 0;
+}
+static inline int probe_irq_off(unsigned long val)
+{
+ return 0;
+}
+static inline unsigned int probe_irq_mask(unsigned long val)
+{
+ return 0;
+}
+#else
+extern unsigned long probe_irq_on(void); /* returns 0 on failure */
+extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */
+extern unsigned int probe_irq_mask(unsigned long); /* returns mask of ISA interrupts */
+#endif
+
+#ifdef CONFIG_PROC_FS
+/* Initialize /proc/irq/ */
+extern void init_irq_proc(void);
+#else
+static inline void init_irq_proc(void)
+{
+}
+#endif
+
+struct seq_file;
+int show_interrupts(struct seq_file *p, void *v);
+int arch_show_interrupts(struct seq_file *p, int prec);
+
+extern int early_irq_init(void);
+extern int arch_probe_nr_irqs(void);
+extern int arch_early_irq_init(void);
+
+#endif