784 строки
24 KiB
C
784 строки
24 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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/* interrupt.h */
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#ifndef _LINUX_INTERRUPT_H
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#define _LINUX_INTERRUPT_H
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#include <linux/kernel.h>
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#include <linux/bitops.h>
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#include <linux/cpumask.h>
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#include <linux/irqreturn.h>
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#include <linux/irqnr.h>
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#include <linux/hardirq.h>
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#include <linux/irqflags.h>
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#include <linux/hrtimer.h>
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#include <linux/kref.h>
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#include <linux/workqueue.h>
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#include <linux/jump_label.h>
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#include <linux/atomic.h>
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#include <asm/ptrace.h>
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#include <asm/irq.h>
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#include <asm/sections.h>
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/*
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* These correspond to the IORESOURCE_IRQ_* defines in
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* linux/ioport.h to select the interrupt line behaviour. When
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* requesting an interrupt without specifying a IRQF_TRIGGER, the
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* setting should be assumed to be "as already configured", which
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* may be as per machine or firmware initialisation.
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*/
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#define IRQF_TRIGGER_NONE 0x00000000
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#define IRQF_TRIGGER_RISING 0x00000001
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#define IRQF_TRIGGER_FALLING 0x00000002
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#define IRQF_TRIGGER_HIGH 0x00000004
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#define IRQF_TRIGGER_LOW 0x00000008
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#define IRQF_TRIGGER_MASK (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW | \
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IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
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#define IRQF_TRIGGER_PROBE 0x00000010
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/*
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* These flags used only by the kernel as part of the
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* irq handling routines.
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*
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* IRQF_SHARED - allow sharing the irq among several devices
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* IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
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* IRQF_TIMER - Flag to mark this interrupt as timer interrupt
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* IRQF_PERCPU - Interrupt is per cpu
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* IRQF_NOBALANCING - Flag to exclude this interrupt from irq balancing
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* IRQF_IRQPOLL - Interrupt is used for polling (only the interrupt that is
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* registered first in a shared interrupt is considered for
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* performance reasons)
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* IRQF_ONESHOT - Interrupt is not reenabled after the hardirq handler finished.
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* Used by threaded interrupts which need to keep the
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* irq line disabled until the threaded handler has been run.
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* IRQF_NO_SUSPEND - Do not disable this IRQ during suspend. Does not guarantee
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* that this interrupt will wake the system from a suspended
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* state. See Documentation/power/suspend-and-interrupts.rst
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* IRQF_FORCE_RESUME - Force enable it on resume even if IRQF_NO_SUSPEND is set
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* IRQF_NO_THREAD - Interrupt cannot be threaded
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* IRQF_EARLY_RESUME - Resume IRQ early during syscore instead of at device
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* resume time.
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* IRQF_COND_SUSPEND - If the IRQ is shared with a NO_SUSPEND user, execute this
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* interrupt handler after suspending interrupts. For system
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* wakeup devices users need to implement wakeup detection in
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* their interrupt handlers.
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* IRQF_NO_AUTOEN - Don't enable IRQ or NMI automatically when users request it.
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* Users will enable it explicitly by enable_irq() or enable_nmi()
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* later.
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* IRQF_NO_DEBUG - Exclude from runnaway detection for IPI and similar handlers,
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* depends on IRQF_PERCPU.
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*/
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#define IRQF_SHARED 0x00000080
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#define IRQF_PROBE_SHARED 0x00000100
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#define __IRQF_TIMER 0x00000200
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#define IRQF_PERCPU 0x00000400
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#define IRQF_NOBALANCING 0x00000800
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#define IRQF_IRQPOLL 0x00001000
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#define IRQF_ONESHOT 0x00002000
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#define IRQF_NO_SUSPEND 0x00004000
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#define IRQF_FORCE_RESUME 0x00008000
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#define IRQF_NO_THREAD 0x00010000
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#define IRQF_EARLY_RESUME 0x00020000
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#define IRQF_COND_SUSPEND 0x00040000
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#define IRQF_NO_AUTOEN 0x00080000
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#define IRQF_NO_DEBUG 0x00100000
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#define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD)
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/*
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* These values can be returned by request_any_context_irq() and
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* describe the context the interrupt will be run in.
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*
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* IRQC_IS_HARDIRQ - interrupt runs in hardirq context
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* IRQC_IS_NESTED - interrupt runs in a nested threaded context
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*/
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enum {
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IRQC_IS_HARDIRQ = 0,
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IRQC_IS_NESTED,
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};
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typedef irqreturn_t (*irq_handler_t)(int, void *);
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/**
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* struct irqaction - per interrupt action descriptor
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* @handler: interrupt handler function
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* @name: name of the device
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* @dev_id: cookie to identify the device
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* @percpu_dev_id: cookie to identify the device
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* @next: pointer to the next irqaction for shared interrupts
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* @irq: interrupt number
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* @flags: flags (see IRQF_* above)
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* @thread_fn: interrupt handler function for threaded interrupts
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* @thread: thread pointer for threaded interrupts
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* @secondary: pointer to secondary irqaction (force threading)
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* @thread_flags: flags related to @thread
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* @thread_mask: bitmask for keeping track of @thread activity
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* @dir: pointer to the proc/irq/NN/name entry
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*/
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struct irqaction {
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irq_handler_t handler;
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void *dev_id;
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void __percpu *percpu_dev_id;
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struct irqaction *next;
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irq_handler_t thread_fn;
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struct task_struct *thread;
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struct irqaction *secondary;
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unsigned int irq;
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unsigned int flags;
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unsigned long thread_flags;
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unsigned long thread_mask;
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const char *name;
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struct proc_dir_entry *dir;
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} ____cacheline_internodealigned_in_smp;
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extern irqreturn_t no_action(int cpl, void *dev_id);
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/*
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* If a (PCI) device interrupt is not connected we set dev->irq to
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* IRQ_NOTCONNECTED. This causes request_irq() to fail with -ENOTCONN, so we
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* can distingiush that case from other error returns.
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*
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* 0x80000000 is guaranteed to be outside the available range of interrupts
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* and easy to distinguish from other possible incorrect values.
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*/
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#define IRQ_NOTCONNECTED (1U << 31)
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extern int __must_check
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request_threaded_irq(unsigned int irq, irq_handler_t handler,
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irq_handler_t thread_fn,
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unsigned long flags, const char *name, void *dev);
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/**
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* request_irq - Add a handler for an interrupt line
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* @irq: The interrupt line to allocate
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* @handler: Function to be called when the IRQ occurs.
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* Primary handler for threaded interrupts
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* If NULL, the default primary handler is installed
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* @flags: Handling flags
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* @name: Name of the device generating this interrupt
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* @dev: A cookie passed to the handler function
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*
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* This call allocates an interrupt and establishes a handler; see
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* the documentation for request_threaded_irq() for details.
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*/
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static inline int __must_check
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request_irq(unsigned int irq, irq_handler_t handler, unsigned long flags,
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const char *name, void *dev)
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{
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return request_threaded_irq(irq, handler, NULL, flags, name, dev);
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}
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extern int __must_check
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request_any_context_irq(unsigned int irq, irq_handler_t handler,
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unsigned long flags, const char *name, void *dev_id);
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extern int __must_check
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__request_percpu_irq(unsigned int irq, irq_handler_t handler,
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unsigned long flags, const char *devname,
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void __percpu *percpu_dev_id);
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extern int __must_check
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request_nmi(unsigned int irq, irq_handler_t handler, unsigned long flags,
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const char *name, void *dev);
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static inline int __must_check
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request_percpu_irq(unsigned int irq, irq_handler_t handler,
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const char *devname, void __percpu *percpu_dev_id)
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{
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return __request_percpu_irq(irq, handler, 0,
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devname, percpu_dev_id);
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}
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extern int __must_check
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request_percpu_nmi(unsigned int irq, irq_handler_t handler,
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const char *devname, void __percpu *dev);
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extern const void *free_irq(unsigned int, void *);
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extern void free_percpu_irq(unsigned int, void __percpu *);
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extern const void *free_nmi(unsigned int irq, void *dev_id);
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extern void free_percpu_nmi(unsigned int irq, void __percpu *percpu_dev_id);
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struct device;
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extern int __must_check
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devm_request_threaded_irq(struct device *dev, unsigned int irq,
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irq_handler_t handler, irq_handler_t thread_fn,
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unsigned long irqflags, const char *devname,
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void *dev_id);
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static inline int __must_check
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devm_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler,
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unsigned long irqflags, const char *devname, void *dev_id)
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{
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return devm_request_threaded_irq(dev, irq, handler, NULL, irqflags,
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devname, dev_id);
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}
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extern int __must_check
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devm_request_any_context_irq(struct device *dev, unsigned int irq,
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irq_handler_t handler, unsigned long irqflags,
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const char *devname, void *dev_id);
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extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id);
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/*
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* On lockdep we dont want to enable hardirqs in hardirq
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* context. Use local_irq_enable_in_hardirq() to annotate
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* kernel code that has to do this nevertheless (pretty much
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* the only valid case is for old/broken hardware that is
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* insanely slow).
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*
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* NOTE: in theory this might break fragile code that relies
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* on hardirq delivery - in practice we dont seem to have such
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* places left. So the only effect should be slightly increased
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* irqs-off latencies.
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*/
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#ifdef CONFIG_LOCKDEP
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# define local_irq_enable_in_hardirq() do { } while (0)
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#else
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# define local_irq_enable_in_hardirq() local_irq_enable()
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#endif
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bool irq_has_action(unsigned int irq);
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extern void disable_irq_nosync(unsigned int irq);
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extern bool disable_hardirq(unsigned int irq);
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extern void disable_irq(unsigned int irq);
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extern void disable_percpu_irq(unsigned int irq);
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extern void enable_irq(unsigned int irq);
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extern void enable_percpu_irq(unsigned int irq, unsigned int type);
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extern bool irq_percpu_is_enabled(unsigned int irq);
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extern void irq_wake_thread(unsigned int irq, void *dev_id);
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extern void disable_nmi_nosync(unsigned int irq);
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extern void disable_percpu_nmi(unsigned int irq);
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extern void enable_nmi(unsigned int irq);
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extern void enable_percpu_nmi(unsigned int irq, unsigned int type);
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extern int prepare_percpu_nmi(unsigned int irq);
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extern void teardown_percpu_nmi(unsigned int irq);
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extern int irq_inject_interrupt(unsigned int irq);
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/* The following three functions are for the core kernel use only. */
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extern void suspend_device_irqs(void);
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extern void resume_device_irqs(void);
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extern void rearm_wake_irq(unsigned int irq);
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/**
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* struct irq_affinity_notify - context for notification of IRQ affinity changes
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* @irq: Interrupt to which notification applies
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* @kref: Reference count, for internal use
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* @work: Work item, for internal use
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* @notify: Function to be called on change. This will be
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* called in process context.
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* @release: Function to be called on release. This will be
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* called in process context. Once registered, the
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* structure must only be freed when this function is
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* called or later.
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*/
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struct irq_affinity_notify {
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unsigned int irq;
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struct kref kref;
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struct work_struct work;
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void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask);
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void (*release)(struct kref *ref);
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};
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#define IRQ_AFFINITY_MAX_SETS 4
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/**
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* struct irq_affinity - Description for automatic irq affinity assignements
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* @pre_vectors: Don't apply affinity to @pre_vectors at beginning of
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* the MSI(-X) vector space
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* @post_vectors: Don't apply affinity to @post_vectors at end of
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* the MSI(-X) vector space
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* @nr_sets: The number of interrupt sets for which affinity
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* spreading is required
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* @set_size: Array holding the size of each interrupt set
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* @calc_sets: Callback for calculating the number and size
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* of interrupt sets
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* @priv: Private data for usage by @calc_sets, usually a
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* pointer to driver/device specific data.
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*/
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struct irq_affinity {
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unsigned int pre_vectors;
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unsigned int post_vectors;
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unsigned int nr_sets;
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unsigned int set_size[IRQ_AFFINITY_MAX_SETS];
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void (*calc_sets)(struct irq_affinity *, unsigned int nvecs);
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void *priv;
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};
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/**
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* struct irq_affinity_desc - Interrupt affinity descriptor
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* @mask: cpumask to hold the affinity assignment
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* @is_managed: 1 if the interrupt is managed internally
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*/
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struct irq_affinity_desc {
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struct cpumask mask;
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unsigned int is_managed : 1;
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};
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#if defined(CONFIG_SMP)
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extern cpumask_var_t irq_default_affinity;
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extern int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask);
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extern int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask);
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extern int irq_can_set_affinity(unsigned int irq);
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extern int irq_select_affinity(unsigned int irq);
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extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m);
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extern int irq_update_affinity_desc(unsigned int irq,
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struct irq_affinity_desc *affinity);
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extern int
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irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);
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struct irq_affinity_desc *
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irq_create_affinity_masks(unsigned int nvec, struct irq_affinity *affd);
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unsigned int irq_calc_affinity_vectors(unsigned int minvec, unsigned int maxvec,
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const struct irq_affinity *affd);
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#else /* CONFIG_SMP */
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static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)
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{
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return -EINVAL;
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}
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static inline int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
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{
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return 0;
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}
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static inline int irq_can_set_affinity(unsigned int irq)
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{
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return 0;
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}
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static inline int irq_select_affinity(unsigned int irq) { return 0; }
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static inline int irq_set_affinity_hint(unsigned int irq,
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const struct cpumask *m)
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{
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return -EINVAL;
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}
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static inline int irq_update_affinity_desc(unsigned int irq,
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struct irq_affinity_desc *affinity)
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{
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return -EINVAL;
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}
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static inline int
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irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
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{
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return 0;
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}
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static inline struct irq_affinity_desc *
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irq_create_affinity_masks(unsigned int nvec, struct irq_affinity *affd)
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{
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return NULL;
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}
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static inline unsigned int
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irq_calc_affinity_vectors(unsigned int minvec, unsigned int maxvec,
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const struct irq_affinity *affd)
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{
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return maxvec;
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}
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#endif /* CONFIG_SMP */
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/*
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* Special lockdep variants of irq disabling/enabling.
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* These should be used for locking constructs that
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* know that a particular irq context which is disabled,
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* and which is the only irq-context user of a lock,
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* that it's safe to take the lock in the irq-disabled
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* section without disabling hardirqs.
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*
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* On !CONFIG_LOCKDEP they are equivalent to the normal
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* irq disable/enable methods.
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*/
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static inline void disable_irq_nosync_lockdep(unsigned int irq)
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{
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disable_irq_nosync(irq);
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#ifdef CONFIG_LOCKDEP
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local_irq_disable();
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#endif
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}
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static inline void disable_irq_nosync_lockdep_irqsave(unsigned int irq, unsigned long *flags)
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{
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disable_irq_nosync(irq);
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#ifdef CONFIG_LOCKDEP
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local_irq_save(*flags);
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#endif
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}
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static inline void disable_irq_lockdep(unsigned int irq)
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{
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disable_irq(irq);
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#ifdef CONFIG_LOCKDEP
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local_irq_disable();
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#endif
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}
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static inline void enable_irq_lockdep(unsigned int irq)
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{
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#ifdef CONFIG_LOCKDEP
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local_irq_enable();
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#endif
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enable_irq(irq);
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}
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static inline void enable_irq_lockdep_irqrestore(unsigned int irq, unsigned long *flags)
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{
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#ifdef CONFIG_LOCKDEP
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local_irq_restore(*flags);
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#endif
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enable_irq(irq);
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}
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/* IRQ wakeup (PM) control: */
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extern int irq_set_irq_wake(unsigned int irq, unsigned int on);
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static inline int enable_irq_wake(unsigned int irq)
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{
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return irq_set_irq_wake(irq, 1);
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}
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static inline int disable_irq_wake(unsigned int irq)
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{
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return irq_set_irq_wake(irq, 0);
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}
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/*
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* irq_get_irqchip_state/irq_set_irqchip_state specific flags
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*/
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enum irqchip_irq_state {
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IRQCHIP_STATE_PENDING, /* Is interrupt pending? */
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IRQCHIP_STATE_ACTIVE, /* Is interrupt in progress? */
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IRQCHIP_STATE_MASKED, /* Is interrupt masked? */
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IRQCHIP_STATE_LINE_LEVEL, /* Is IRQ line high? */
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};
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extern int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
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bool *state);
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extern int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
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bool state);
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#ifdef CONFIG_IRQ_FORCED_THREADING
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# ifdef CONFIG_PREEMPT_RT
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# define force_irqthreads() (true)
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# else
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DECLARE_STATIC_KEY_FALSE(force_irqthreads_key);
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# define force_irqthreads() (static_branch_unlikely(&force_irqthreads_key))
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# endif
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#else
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#define force_irqthreads() (false)
|
|
#endif
|
|
|
|
#ifndef local_softirq_pending
|
|
|
|
#ifndef local_softirq_pending_ref
|
|
#define local_softirq_pending_ref irq_stat.__softirq_pending
|
|
#endif
|
|
|
|
#define local_softirq_pending() (__this_cpu_read(local_softirq_pending_ref))
|
|
#define set_softirq_pending(x) (__this_cpu_write(local_softirq_pending_ref, (x)))
|
|
#define or_softirq_pending(x) (__this_cpu_or(local_softirq_pending_ref, (x)))
|
|
|
|
#endif /* local_softirq_pending */
|
|
|
|
/* 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,
|
|
IRQ_POLL_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 *);
|
|
};
|
|
|
|
asmlinkage void do_softirq(void);
|
|
asmlinkage void __do_softirq(void);
|
|
|
|
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);
|
|
|
|
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.
|
|
|
|
This API is deprecated. Please consider using threaded IRQs instead:
|
|
https://lore.kernel.org/lkml/20200716081538.2sivhkj4hcyrusem@linutronix.de
|
|
|
|
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 (or schedule is called
|
|
from tasklet itself), it is rescheduled for later.
|
|
* 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;
|
|
bool use_callback;
|
|
union {
|
|
void (*func)(unsigned long data);
|
|
void (*callback)(struct tasklet_struct *t);
|
|
};
|
|
unsigned long data;
|
|
};
|
|
|
|
#define DECLARE_TASKLET(name, _callback) \
|
|
struct tasklet_struct name = { \
|
|
.count = ATOMIC_INIT(0), \
|
|
.callback = _callback, \
|
|
.use_callback = true, \
|
|
}
|
|
|
|
#define DECLARE_TASKLET_DISABLED(name, _callback) \
|
|
struct tasklet_struct name = { \
|
|
.count = ATOMIC_INIT(1), \
|
|
.callback = _callback, \
|
|
.use_callback = true, \
|
|
}
|
|
|
|
#define from_tasklet(var, callback_tasklet, tasklet_fieldname) \
|
|
container_of(callback_tasklet, typeof(*var), tasklet_fieldname)
|
|
|
|
#define DECLARE_TASKLET_OLD(name, _func) \
|
|
struct tasklet_struct name = { \
|
|
.count = ATOMIC_INIT(0), \
|
|
.func = _func, \
|
|
}
|
|
|
|
#define DECLARE_TASKLET_DISABLED_OLD(name, _func) \
|
|
struct tasklet_struct name = { \
|
|
.count = ATOMIC_INIT(1), \
|
|
.func = _func, \
|
|
}
|
|
|
|
enum
|
|
{
|
|
TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */
|
|
TASKLET_STATE_RUN /* Tasklet is running (SMP only) */
|
|
};
|
|
|
|
#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
|
|
static inline int tasklet_trylock(struct tasklet_struct *t)
|
|
{
|
|
return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
|
|
}
|
|
|
|
void tasklet_unlock(struct tasklet_struct *t);
|
|
void tasklet_unlock_wait(struct tasklet_struct *t);
|
|
void tasklet_unlock_spin_wait(struct tasklet_struct *t);
|
|
|
|
#else
|
|
static inline int tasklet_trylock(struct tasklet_struct *t) { return 1; }
|
|
static inline void tasklet_unlock(struct tasklet_struct *t) { }
|
|
static inline void tasklet_unlock_wait(struct tasklet_struct *t) { }
|
|
static inline void tasklet_unlock_spin_wait(struct tasklet_struct *t) { }
|
|
#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);
|
|
}
|
|
|
|
static inline void tasklet_disable_nosync(struct tasklet_struct *t)
|
|
{
|
|
atomic_inc(&t->count);
|
|
smp_mb__after_atomic();
|
|
}
|
|
|
|
/*
|
|
* Do not use in new code. Disabling tasklets from atomic contexts is
|
|
* error prone and should be avoided.
|
|
*/
|
|
static inline void tasklet_disable_in_atomic(struct tasklet_struct *t)
|
|
{
|
|
tasklet_disable_nosync(t);
|
|
tasklet_unlock_spin_wait(t);
|
|
smp_mb();
|
|
}
|
|
|
|
static inline void tasklet_disable(struct tasklet_struct *t)
|
|
{
|
|
tasklet_disable_nosync(t);
|
|
tasklet_unlock_wait(t);
|
|
smp_mb();
|
|
}
|
|
|
|
static inline void tasklet_enable(struct tasklet_struct *t)
|
|
{
|
|
smp_mb__before_atomic();
|
|
atomic_dec(&t->count);
|
|
}
|
|
|
|
extern void tasklet_kill(struct tasklet_struct *t);
|
|
extern void tasklet_init(struct tasklet_struct *t,
|
|
void (*func)(unsigned long), unsigned long data);
|
|
extern void tasklet_setup(struct tasklet_struct *t,
|
|
void (*callback)(struct tasklet_struct *));
|
|
|
|
/*
|
|
* 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
|
|
|
|
#ifdef CONFIG_IRQ_TIMINGS
|
|
void irq_timings_enable(void);
|
|
void irq_timings_disable(void);
|
|
u64 irq_timings_next_event(u64 now);
|
|
#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);
|
|
|
|
/*
|
|
* We want to know which function is an entrypoint of a hardirq or a softirq.
|
|
*/
|
|
#ifndef __irq_entry
|
|
# define __irq_entry __section(".irqentry.text")
|
|
#endif
|
|
|
|
#define __softirq_entry __section(".softirqentry.text")
|
|
|
|
#endif
|