1039 lines
24 KiB
C
1039 lines
24 KiB
C
![]() |
/*
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* linux/arch/arm/kernel/irq.c
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*
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* Copyright (C) 1992 Linus Torvalds
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* Modifications for ARM processor Copyright (C) 1995-2000 Russell King.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This file contains the code used by various IRQ handling routines:
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* asking for different IRQ's should be done through these routines
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* instead of just grabbing them. Thus setups with different IRQ numbers
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* shouldn't result in any weird surprises, and installing new handlers
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* should be easier.
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*
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* IRQ's are in fact implemented a bit like signal handlers for the kernel.
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* Naturally it's not a 1:1 relation, but there are similarities.
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*/
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#include <linux/config.h>
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#include <linux/kernel_stat.h>
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#include <linux/module.h>
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#include <linux/signal.h>
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#include <linux/ioport.h>
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#include <linux/interrupt.h>
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#include <linux/ptrace.h>
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#include <linux/slab.h>
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#include <linux/random.h>
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#include <linux/smp.h>
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#include <linux/init.h>
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#include <linux/seq_file.h>
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#include <linux/errno.h>
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#include <linux/list.h>
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#include <linux/kallsyms.h>
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#include <linux/proc_fs.h>
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#include <asm/irq.h>
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#include <asm/system.h>
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#include <asm/mach/irq.h>
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/*
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* Maximum IRQ count. Currently, this is arbitary. However, it should
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* not be set too low to prevent false triggering. Conversely, if it
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* is set too high, then you could miss a stuck IRQ.
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*
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* Maybe we ought to set a timer and re-enable the IRQ at a later time?
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*/
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#define MAX_IRQ_CNT 100000
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static int noirqdebug;
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static volatile unsigned long irq_err_count;
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static DEFINE_SPINLOCK(irq_controller_lock);
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static LIST_HEAD(irq_pending);
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struct irqdesc irq_desc[NR_IRQS];
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void (*init_arch_irq)(void) __initdata = NULL;
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/*
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* No architecture-specific irq_finish function defined in arm/arch/irqs.h.
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*/
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#ifndef irq_finish
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#define irq_finish(irq) do { } while (0)
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#endif
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/*
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* Dummy mask/unmask handler
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*/
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void dummy_mask_unmask_irq(unsigned int irq)
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{
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}
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irqreturn_t no_action(int irq, void *dev_id, struct pt_regs *regs)
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{
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return IRQ_NONE;
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}
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void do_bad_IRQ(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
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{
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irq_err_count += 1;
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printk(KERN_ERR "IRQ: spurious interrupt %d\n", irq);
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}
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static struct irqchip bad_chip = {
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.ack = dummy_mask_unmask_irq,
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.mask = dummy_mask_unmask_irq,
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.unmask = dummy_mask_unmask_irq,
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};
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static struct irqdesc bad_irq_desc = {
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.chip = &bad_chip,
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.handle = do_bad_IRQ,
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.pend = LIST_HEAD_INIT(bad_irq_desc.pend),
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.disable_depth = 1,
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};
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#ifdef CONFIG_SMP
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void synchronize_irq(unsigned int irq)
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{
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struct irqdesc *desc = irq_desc + irq;
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while (desc->running)
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barrier();
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}
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EXPORT_SYMBOL(synchronize_irq);
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#define smp_set_running(desc) do { desc->running = 1; } while (0)
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#define smp_clear_running(desc) do { desc->running = 0; } while (0)
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#else
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#define smp_set_running(desc) do { } while (0)
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#define smp_clear_running(desc) do { } while (0)
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#endif
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/**
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* disable_irq_nosync - disable an irq without waiting
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* @irq: Interrupt to disable
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*
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* Disable the selected interrupt line. Enables and disables
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* are nested. We do this lazily.
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*
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* This function may be called from IRQ context.
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*/
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void disable_irq_nosync(unsigned int irq)
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{
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struct irqdesc *desc = irq_desc + irq;
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unsigned long flags;
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spin_lock_irqsave(&irq_controller_lock, flags);
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desc->disable_depth++;
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list_del_init(&desc->pend);
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spin_unlock_irqrestore(&irq_controller_lock, flags);
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}
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EXPORT_SYMBOL(disable_irq_nosync);
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/**
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* disable_irq - disable an irq and wait for completion
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* @irq: Interrupt to disable
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*
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* Disable the selected interrupt line. Enables and disables
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* are nested. This functions waits for any pending IRQ
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* handlers for this interrupt to complete before returning.
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* If you use this function while holding a resource the IRQ
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* handler may need you will deadlock.
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*
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* This function may be called - with care - from IRQ context.
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*/
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void disable_irq(unsigned int irq)
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{
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struct irqdesc *desc = irq_desc + irq;
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disable_irq_nosync(irq);
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if (desc->action)
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synchronize_irq(irq);
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}
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EXPORT_SYMBOL(disable_irq);
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/**
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* enable_irq - enable interrupt handling on an irq
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* @irq: Interrupt to enable
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*
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* Re-enables the processing of interrupts on this IRQ line.
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* Note that this may call the interrupt handler, so you may
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* get unexpected results if you hold IRQs disabled.
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*
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* This function may be called from IRQ context.
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*/
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void enable_irq(unsigned int irq)
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{
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struct irqdesc *desc = irq_desc + irq;
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unsigned long flags;
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spin_lock_irqsave(&irq_controller_lock, flags);
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if (unlikely(!desc->disable_depth)) {
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printk("enable_irq(%u) unbalanced from %p\n", irq,
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__builtin_return_address(0));
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} else if (!--desc->disable_depth) {
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desc->probing = 0;
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desc->chip->unmask(irq);
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/*
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* If the interrupt is waiting to be processed,
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* try to re-run it. We can't directly run it
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* from here since the caller might be in an
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* interrupt-protected region.
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*/
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if (desc->pending && list_empty(&desc->pend)) {
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desc->pending = 0;
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if (!desc->chip->retrigger ||
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desc->chip->retrigger(irq))
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list_add(&desc->pend, &irq_pending);
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}
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}
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spin_unlock_irqrestore(&irq_controller_lock, flags);
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}
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EXPORT_SYMBOL(enable_irq);
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/*
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* Enable wake on selected irq
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*/
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void enable_irq_wake(unsigned int irq)
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{
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struct irqdesc *desc = irq_desc + irq;
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unsigned long flags;
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spin_lock_irqsave(&irq_controller_lock, flags);
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if (desc->chip->wake)
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desc->chip->wake(irq, 1);
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spin_unlock_irqrestore(&irq_controller_lock, flags);
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}
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EXPORT_SYMBOL(enable_irq_wake);
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void disable_irq_wake(unsigned int irq)
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{
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struct irqdesc *desc = irq_desc + irq;
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unsigned long flags;
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spin_lock_irqsave(&irq_controller_lock, flags);
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if (desc->chip->wake)
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desc->chip->wake(irq, 0);
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spin_unlock_irqrestore(&irq_controller_lock, flags);
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}
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EXPORT_SYMBOL(disable_irq_wake);
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int show_interrupts(struct seq_file *p, void *v)
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{
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int i = *(loff_t *) v, cpu;
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struct irqaction * action;
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unsigned long flags;
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if (i == 0) {
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char cpuname[12];
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seq_printf(p, " ");
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for_each_present_cpu(cpu) {
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sprintf(cpuname, "CPU%d", cpu);
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seq_printf(p, " %10s", cpuname);
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}
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seq_putc(p, '\n');
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}
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if (i < NR_IRQS) {
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spin_lock_irqsave(&irq_controller_lock, flags);
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action = irq_desc[i].action;
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if (!action)
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goto unlock;
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seq_printf(p, "%3d: ", i);
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for_each_present_cpu(cpu)
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seq_printf(p, "%10u ", kstat_cpu(cpu).irqs[i]);
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seq_printf(p, " %s", action->name);
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for (action = action->next; action; action = action->next)
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seq_printf(p, ", %s", action->name);
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seq_putc(p, '\n');
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unlock:
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spin_unlock_irqrestore(&irq_controller_lock, flags);
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} else if (i == NR_IRQS) {
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#ifdef CONFIG_ARCH_ACORN
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show_fiq_list(p, v);
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#endif
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#ifdef CONFIG_SMP
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show_ipi_list(p);
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#endif
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seq_printf(p, "Err: %10lu\n", irq_err_count);
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}
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return 0;
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}
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/*
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* IRQ lock detection.
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*
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* Hopefully, this should get us out of a few locked situations.
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* However, it may take a while for this to happen, since we need
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* a large number if IRQs to appear in the same jiffie with the
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* same instruction pointer (or within 2 instructions).
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*/
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static int check_irq_lock(struct irqdesc *desc, int irq, struct pt_regs *regs)
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{
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unsigned long instr_ptr = instruction_pointer(regs);
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if (desc->lck_jif == jiffies &&
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desc->lck_pc >= instr_ptr && desc->lck_pc < instr_ptr + 8) {
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desc->lck_cnt += 1;
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if (desc->lck_cnt > MAX_IRQ_CNT) {
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printk(KERN_ERR "IRQ LOCK: IRQ%d is locking the system, disabled\n", irq);
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return 1;
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}
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} else {
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desc->lck_cnt = 0;
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desc->lck_pc = instruction_pointer(regs);
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desc->lck_jif = jiffies;
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}
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return 0;
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}
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static void
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report_bad_irq(unsigned int irq, struct pt_regs *regs, struct irqdesc *desc, int ret)
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{
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static int count = 100;
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struct irqaction *action;
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if (!count || noirqdebug)
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return;
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count--;
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if (ret != IRQ_HANDLED && ret != IRQ_NONE) {
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printk("irq%u: bogus retval mask %x\n", irq, ret);
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} else {
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printk("irq%u: nobody cared\n", irq);
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}
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show_regs(regs);
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dump_stack();
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printk(KERN_ERR "handlers:");
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action = desc->action;
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do {
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printk("\n" KERN_ERR "[<%p>]", action->handler);
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print_symbol(" (%s)", (unsigned long)action->handler);
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action = action->next;
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} while (action);
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printk("\n");
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}
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|
|
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static int
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__do_irq(unsigned int irq, struct irqaction *action, struct pt_regs *regs)
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{
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unsigned int status;
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int ret, retval = 0;
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spin_unlock(&irq_controller_lock);
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if (!(action->flags & SA_INTERRUPT))
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local_irq_enable();
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status = 0;
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do {
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ret = action->handler(irq, action->dev_id, regs);
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if (ret == IRQ_HANDLED)
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status |= action->flags;
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retval |= ret;
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action = action->next;
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} while (action);
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|
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if (status & SA_SAMPLE_RANDOM)
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add_interrupt_randomness(irq);
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spin_lock_irq(&irq_controller_lock);
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return retval;
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}
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|
|
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/*
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* This is for software-decoded IRQs. The caller is expected to
|
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* handle the ack, clear, mask and unmask issues.
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*/
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void
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do_simple_IRQ(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
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{
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struct irqaction *action;
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const unsigned int cpu = smp_processor_id();
|
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|
|
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desc->triggered = 1;
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|
|
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kstat_cpu(cpu).irqs[irq]++;
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|
|
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smp_set_running(desc);
|
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|
|
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action = desc->action;
|
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if (action) {
|
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int ret = __do_irq(irq, action, regs);
|
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if (ret != IRQ_HANDLED)
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report_bad_irq(irq, regs, desc, ret);
|
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}
|
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|
|
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smp_clear_running(desc);
|
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}
|
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|
|
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|
/*
|
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* Most edge-triggered IRQ implementations seem to take a broken
|
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|
* approach to this. Hence the complexity.
|
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|
*/
|
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|
void
|
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|
do_edge_IRQ(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
|
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|
{
|
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|
const unsigned int cpu = smp_processor_id();
|
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|
|
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desc->triggered = 1;
|
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|
|
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|
/*
|
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|
* If we're currently running this IRQ, or its disabled,
|
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|
* we shouldn't process the IRQ. Instead, turn on the
|
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|
* hardware masks.
|
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|
*/
|
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|
if (unlikely(desc->running || desc->disable_depth))
|
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|
goto running;
|
||
|
|
||
|
/*
|
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|
* Acknowledge and clear the IRQ, but don't mask it.
|
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|
*/
|
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|
desc->chip->ack(irq);
|
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|
|
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|
/*
|
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|
* Mark the IRQ currently in progress.
|
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|
*/
|
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|
desc->running = 1;
|
||
|
|
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|
kstat_cpu(cpu).irqs[irq]++;
|
||
|
|
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|
do {
|
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|
struct irqaction *action;
|
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|
|
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|
action = desc->action;
|
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|
if (!action)
|
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|
break;
|
||
|
|
||
|
if (desc->pending && !desc->disable_depth) {
|
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|
desc->pending = 0;
|
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|
desc->chip->unmask(irq);
|
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|
}
|
||
|
|
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|
__do_irq(irq, action, regs);
|
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|
} while (desc->pending && !desc->disable_depth);
|
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|
|
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|
desc->running = 0;
|
||
|
|
||
|
/*
|
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|
* If we were disabled or freed, shut down the handler.
|
||
|
*/
|
||
|
if (likely(desc->action && !check_irq_lock(desc, irq, regs)))
|
||
|
return;
|
||
|
|
||
|
running:
|
||
|
/*
|
||
|
* We got another IRQ while this one was masked or
|
||
|
* currently running. Delay it.
|
||
|
*/
|
||
|
desc->pending = 1;
|
||
|
desc->chip->mask(irq);
|
||
|
desc->chip->ack(irq);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Level-based IRQ handler. Nice and simple.
|
||
|
*/
|
||
|
void
|
||
|
do_level_IRQ(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
|
||
|
{
|
||
|
struct irqaction *action;
|
||
|
const unsigned int cpu = smp_processor_id();
|
||
|
|
||
|
desc->triggered = 1;
|
||
|
|
||
|
/*
|
||
|
* Acknowledge, clear _AND_ disable the interrupt.
|
||
|
*/
|
||
|
desc->chip->ack(irq);
|
||
|
|
||
|
if (likely(!desc->disable_depth)) {
|
||
|
kstat_cpu(cpu).irqs[irq]++;
|
||
|
|
||
|
smp_set_running(desc);
|
||
|
|
||
|
/*
|
||
|
* Return with this interrupt masked if no action
|
||
|
*/
|
||
|
action = desc->action;
|
||
|
if (action) {
|
||
|
int ret = __do_irq(irq, desc->action, regs);
|
||
|
|
||
|
if (ret != IRQ_HANDLED)
|
||
|
report_bad_irq(irq, regs, desc, ret);
|
||
|
|
||
|
if (likely(!desc->disable_depth &&
|
||
|
!check_irq_lock(desc, irq, regs)))
|
||
|
desc->chip->unmask(irq);
|
||
|
}
|
||
|
|
||
|
smp_clear_running(desc);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
static void do_pending_irqs(struct pt_regs *regs)
|
||
|
{
|
||
|
struct list_head head, *l, *n;
|
||
|
|
||
|
do {
|
||
|
struct irqdesc *desc;
|
||
|
|
||
|
/*
|
||
|
* First, take the pending interrupts off the list.
|
||
|
* The act of calling the handlers may add some IRQs
|
||
|
* back onto the list.
|
||
|
*/
|
||
|
head = irq_pending;
|
||
|
INIT_LIST_HEAD(&irq_pending);
|
||
|
head.next->prev = &head;
|
||
|
head.prev->next = &head;
|
||
|
|
||
|
/*
|
||
|
* Now run each entry. We must delete it from our
|
||
|
* list before calling the handler.
|
||
|
*/
|
||
|
list_for_each_safe(l, n, &head) {
|
||
|
desc = list_entry(l, struct irqdesc, pend);
|
||
|
list_del_init(&desc->pend);
|
||
|
desc->handle(desc - irq_desc, desc, regs);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* The list must be empty.
|
||
|
*/
|
||
|
BUG_ON(!list_empty(&head));
|
||
|
} while (!list_empty(&irq_pending));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* do_IRQ handles all hardware IRQ's. Decoded IRQs should not
|
||
|
* come via this function. Instead, they should provide their
|
||
|
* own 'handler'
|
||
|
*/
|
||
|
asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs)
|
||
|
{
|
||
|
struct irqdesc *desc = irq_desc + irq;
|
||
|
|
||
|
/*
|
||
|
* Some hardware gives randomly wrong interrupts. Rather
|
||
|
* than crashing, do something sensible.
|
||
|
*/
|
||
|
if (irq >= NR_IRQS)
|
||
|
desc = &bad_irq_desc;
|
||
|
|
||
|
irq_enter();
|
||
|
spin_lock(&irq_controller_lock);
|
||
|
desc->handle(irq, desc, regs);
|
||
|
|
||
|
/*
|
||
|
* Now re-run any pending interrupts.
|
||
|
*/
|
||
|
if (!list_empty(&irq_pending))
|
||
|
do_pending_irqs(regs);
|
||
|
|
||
|
irq_finish(irq);
|
||
|
|
||
|
spin_unlock(&irq_controller_lock);
|
||
|
irq_exit();
|
||
|
}
|
||
|
|
||
|
void __set_irq_handler(unsigned int irq, irq_handler_t handle, int is_chained)
|
||
|
{
|
||
|
struct irqdesc *desc;
|
||
|
unsigned long flags;
|
||
|
|
||
|
if (irq >= NR_IRQS) {
|
||
|
printk(KERN_ERR "Trying to install handler for IRQ%d\n", irq);
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
if (handle == NULL)
|
||
|
handle = do_bad_IRQ;
|
||
|
|
||
|
desc = irq_desc + irq;
|
||
|
|
||
|
if (is_chained && desc->chip == &bad_chip)
|
||
|
printk(KERN_WARNING "Trying to install chained handler for IRQ%d\n", irq);
|
||
|
|
||
|
spin_lock_irqsave(&irq_controller_lock, flags);
|
||
|
if (handle == do_bad_IRQ) {
|
||
|
desc->chip->mask(irq);
|
||
|
desc->chip->ack(irq);
|
||
|
desc->disable_depth = 1;
|
||
|
}
|
||
|
desc->handle = handle;
|
||
|
if (handle != do_bad_IRQ && is_chained) {
|
||
|
desc->valid = 0;
|
||
|
desc->probe_ok = 0;
|
||
|
desc->disable_depth = 0;
|
||
|
desc->chip->unmask(irq);
|
||
|
}
|
||
|
spin_unlock_irqrestore(&irq_controller_lock, flags);
|
||
|
}
|
||
|
|
||
|
void set_irq_chip(unsigned int irq, struct irqchip *chip)
|
||
|
{
|
||
|
struct irqdesc *desc;
|
||
|
unsigned long flags;
|
||
|
|
||
|
if (irq >= NR_IRQS) {
|
||
|
printk(KERN_ERR "Trying to install chip for IRQ%d\n", irq);
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
if (chip == NULL)
|
||
|
chip = &bad_chip;
|
||
|
|
||
|
desc = irq_desc + irq;
|
||
|
spin_lock_irqsave(&irq_controller_lock, flags);
|
||
|
desc->chip = chip;
|
||
|
spin_unlock_irqrestore(&irq_controller_lock, flags);
|
||
|
}
|
||
|
|
||
|
int set_irq_type(unsigned int irq, unsigned int type)
|
||
|
{
|
||
|
struct irqdesc *desc;
|
||
|
unsigned long flags;
|
||
|
int ret = -ENXIO;
|
||
|
|
||
|
if (irq >= NR_IRQS) {
|
||
|
printk(KERN_ERR "Trying to set irq type for IRQ%d\n", irq);
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
|
||
|
desc = irq_desc + irq;
|
||
|
if (desc->chip->type) {
|
||
|
spin_lock_irqsave(&irq_controller_lock, flags);
|
||
|
ret = desc->chip->type(irq, type);
|
||
|
spin_unlock_irqrestore(&irq_controller_lock, flags);
|
||
|
}
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
EXPORT_SYMBOL(set_irq_type);
|
||
|
|
||
|
void set_irq_flags(unsigned int irq, unsigned int iflags)
|
||
|
{
|
||
|
struct irqdesc *desc;
|
||
|
unsigned long flags;
|
||
|
|
||
|
if (irq >= NR_IRQS) {
|
||
|
printk(KERN_ERR "Trying to set irq flags for IRQ%d\n", irq);
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
desc = irq_desc + irq;
|
||
|
spin_lock_irqsave(&irq_controller_lock, flags);
|
||
|
desc->valid = (iflags & IRQF_VALID) != 0;
|
||
|
desc->probe_ok = (iflags & IRQF_PROBE) != 0;
|
||
|
desc->noautoenable = (iflags & IRQF_NOAUTOEN) != 0;
|
||
|
spin_unlock_irqrestore(&irq_controller_lock, flags);
|
||
|
}
|
||
|
|
||
|
int setup_irq(unsigned int irq, struct irqaction *new)
|
||
|
{
|
||
|
int shared = 0;
|
||
|
struct irqaction *old, **p;
|
||
|
unsigned long flags;
|
||
|
struct irqdesc *desc;
|
||
|
|
||
|
/*
|
||
|
* Some drivers like serial.c use request_irq() heavily,
|
||
|
* so we have to be careful not to interfere with a
|
||
|
* running system.
|
||
|
*/
|
||
|
if (new->flags & SA_SAMPLE_RANDOM) {
|
||
|
/*
|
||
|
* This function might sleep, we want to call it first,
|
||
|
* outside of the atomic block.
|
||
|
* Yes, this might clear the entropy pool if the wrong
|
||
|
* driver is attempted to be loaded, without actually
|
||
|
* installing a new handler, but is this really a problem,
|
||
|
* only the sysadmin is able to do this.
|
||
|
*/
|
||
|
rand_initialize_irq(irq);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* The following block of code has to be executed atomically
|
||
|
*/
|
||
|
desc = irq_desc + irq;
|
||
|
spin_lock_irqsave(&irq_controller_lock, flags);
|
||
|
p = &desc->action;
|
||
|
if ((old = *p) != NULL) {
|
||
|
/* Can't share interrupts unless both agree to */
|
||
|
if (!(old->flags & new->flags & SA_SHIRQ)) {
|
||
|
spin_unlock_irqrestore(&irq_controller_lock, flags);
|
||
|
return -EBUSY;
|
||
|
}
|
||
|
|
||
|
/* add new interrupt at end of irq queue */
|
||
|
do {
|
||
|
p = &old->next;
|
||
|
old = *p;
|
||
|
} while (old);
|
||
|
shared = 1;
|
||
|
}
|
||
|
|
||
|
*p = new;
|
||
|
|
||
|
if (!shared) {
|
||
|
desc->probing = 0;
|
||
|
desc->running = 0;
|
||
|
desc->pending = 0;
|
||
|
desc->disable_depth = 1;
|
||
|
if (!desc->noautoenable) {
|
||
|
desc->disable_depth = 0;
|
||
|
desc->chip->unmask(irq);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
spin_unlock_irqrestore(&irq_controller_lock, flags);
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* request_irq - allocate an interrupt line
|
||
|
* @irq: Interrupt line to allocate
|
||
|
* @handler: Function to be called when the IRQ occurs
|
||
|
* @irqflags: Interrupt type flags
|
||
|
* @devname: An ascii name for the claiming device
|
||
|
* @dev_id: A cookie passed back to the handler function
|
||
|
*
|
||
|
* This call allocates interrupt resources and enables the
|
||
|
* interrupt line and IRQ handling. From the point this
|
||
|
* call is made your handler function may be invoked. Since
|
||
|
* your handler function must clear any interrupt the board
|
||
|
* raises, you must take care both to initialise your hardware
|
||
|
* and to set up the interrupt handler in the right order.
|
||
|
*
|
||
|
* Dev_id must be globally unique. Normally the address of the
|
||
|
* device data structure is used as the cookie. Since the handler
|
||
|
* receives this value it makes sense to use it.
|
||
|
*
|
||
|
* If your interrupt is shared you must pass a non NULL dev_id
|
||
|
* as this is required when freeing the interrupt.
|
||
|
*
|
||
|
* Flags:
|
||
|
*
|
||
|
* SA_SHIRQ Interrupt is shared
|
||
|
*
|
||
|
* SA_INTERRUPT Disable local interrupts while processing
|
||
|
*
|
||
|
* SA_SAMPLE_RANDOM The interrupt can be used for entropy
|
||
|
*
|
||
|
*/
|
||
|
int request_irq(unsigned int irq, irqreturn_t (*handler)(int, void *, struct pt_regs *),
|
||
|
unsigned long irq_flags, const char * devname, void *dev_id)
|
||
|
{
|
||
|
unsigned long retval;
|
||
|
struct irqaction *action;
|
||
|
|
||
|
if (irq >= NR_IRQS || !irq_desc[irq].valid || !handler ||
|
||
|
(irq_flags & SA_SHIRQ && !dev_id))
|
||
|
return -EINVAL;
|
||
|
|
||
|
action = (struct irqaction *)kmalloc(sizeof(struct irqaction), GFP_KERNEL);
|
||
|
if (!action)
|
||
|
return -ENOMEM;
|
||
|
|
||
|
action->handler = handler;
|
||
|
action->flags = irq_flags;
|
||
|
cpus_clear(action->mask);
|
||
|
action->name = devname;
|
||
|
action->next = NULL;
|
||
|
action->dev_id = dev_id;
|
||
|
|
||
|
retval = setup_irq(irq, action);
|
||
|
|
||
|
if (retval)
|
||
|
kfree(action);
|
||
|
return retval;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(request_irq);
|
||
|
|
||
|
/**
|
||
|
* free_irq - free an interrupt
|
||
|
* @irq: Interrupt line to free
|
||
|
* @dev_id: Device identity to free
|
||
|
*
|
||
|
* Remove an interrupt handler. The handler is removed and if the
|
||
|
* interrupt line is no longer in use by any driver it is disabled.
|
||
|
* On a shared IRQ the caller must ensure the interrupt is disabled
|
||
|
* on the card it drives before calling this function.
|
||
|
*
|
||
|
* This function must not be called from interrupt context.
|
||
|
*/
|
||
|
void free_irq(unsigned int irq, void *dev_id)
|
||
|
{
|
||
|
struct irqaction * action, **p;
|
||
|
unsigned long flags;
|
||
|
|
||
|
if (irq >= NR_IRQS || !irq_desc[irq].valid) {
|
||
|
printk(KERN_ERR "Trying to free IRQ%d\n",irq);
|
||
|
dump_stack();
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
spin_lock_irqsave(&irq_controller_lock, flags);
|
||
|
for (p = &irq_desc[irq].action; (action = *p) != NULL; p = &action->next) {
|
||
|
if (action->dev_id != dev_id)
|
||
|
continue;
|
||
|
|
||
|
/* Found it - now free it */
|
||
|
*p = action->next;
|
||
|
break;
|
||
|
}
|
||
|
spin_unlock_irqrestore(&irq_controller_lock, flags);
|
||
|
|
||
|
if (!action) {
|
||
|
printk(KERN_ERR "Trying to free free IRQ%d\n",irq);
|
||
|
dump_stack();
|
||
|
} else {
|
||
|
synchronize_irq(irq);
|
||
|
kfree(action);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(free_irq);
|
||
|
|
||
|
static DECLARE_MUTEX(probe_sem);
|
||
|
|
||
|
/* Start the interrupt probing. Unlike other architectures,
|
||
|
* we don't return a mask of interrupts from probe_irq_on,
|
||
|
* but return the number of interrupts enabled for the probe.
|
||
|
* The interrupts which have been enabled for probing is
|
||
|
* instead recorded in the irq_desc structure.
|
||
|
*/
|
||
|
unsigned long probe_irq_on(void)
|
||
|
{
|
||
|
unsigned int i, irqs = 0;
|
||
|
unsigned long delay;
|
||
|
|
||
|
down(&probe_sem);
|
||
|
|
||
|
/*
|
||
|
* first snaffle up any unassigned but
|
||
|
* probe-able interrupts
|
||
|
*/
|
||
|
spin_lock_irq(&irq_controller_lock);
|
||
|
for (i = 0; i < NR_IRQS; i++) {
|
||
|
if (!irq_desc[i].probe_ok || irq_desc[i].action)
|
||
|
continue;
|
||
|
|
||
|
irq_desc[i].probing = 1;
|
||
|
irq_desc[i].triggered = 0;
|
||
|
if (irq_desc[i].chip->type)
|
||
|
irq_desc[i].chip->type(i, IRQT_PROBE);
|
||
|
irq_desc[i].chip->unmask(i);
|
||
|
irqs += 1;
|
||
|
}
|
||
|
spin_unlock_irq(&irq_controller_lock);
|
||
|
|
||
|
/*
|
||
|
* wait for spurious interrupts to mask themselves out again
|
||
|
*/
|
||
|
for (delay = jiffies + HZ/10; time_before(jiffies, delay); )
|
||
|
/* min 100ms delay */;
|
||
|
|
||
|
/*
|
||
|
* now filter out any obviously spurious interrupts
|
||
|
*/
|
||
|
spin_lock_irq(&irq_controller_lock);
|
||
|
for (i = 0; i < NR_IRQS; i++) {
|
||
|
if (irq_desc[i].probing && irq_desc[i].triggered) {
|
||
|
irq_desc[i].probing = 0;
|
||
|
irqs -= 1;
|
||
|
}
|
||
|
}
|
||
|
spin_unlock_irq(&irq_controller_lock);
|
||
|
|
||
|
return irqs;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(probe_irq_on);
|
||
|
|
||
|
unsigned int probe_irq_mask(unsigned long irqs)
|
||
|
{
|
||
|
unsigned int mask = 0, i;
|
||
|
|
||
|
spin_lock_irq(&irq_controller_lock);
|
||
|
for (i = 0; i < 16 && i < NR_IRQS; i++)
|
||
|
if (irq_desc[i].probing && irq_desc[i].triggered)
|
||
|
mask |= 1 << i;
|
||
|
spin_unlock_irq(&irq_controller_lock);
|
||
|
|
||
|
up(&probe_sem);
|
||
|
|
||
|
return mask;
|
||
|
}
|
||
|
EXPORT_SYMBOL(probe_irq_mask);
|
||
|
|
||
|
/*
|
||
|
* Possible return values:
|
||
|
* >= 0 - interrupt number
|
||
|
* -1 - no interrupt/many interrupts
|
||
|
*/
|
||
|
int probe_irq_off(unsigned long irqs)
|
||
|
{
|
||
|
unsigned int i;
|
||
|
int irq_found = NO_IRQ;
|
||
|
|
||
|
/*
|
||
|
* look at the interrupts, and find exactly one
|
||
|
* that we were probing has been triggered
|
||
|
*/
|
||
|
spin_lock_irq(&irq_controller_lock);
|
||
|
for (i = 0; i < NR_IRQS; i++) {
|
||
|
if (irq_desc[i].probing &&
|
||
|
irq_desc[i].triggered) {
|
||
|
if (irq_found != NO_IRQ) {
|
||
|
irq_found = NO_IRQ;
|
||
|
goto out;
|
||
|
}
|
||
|
irq_found = i;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (irq_found == -1)
|
||
|
irq_found = NO_IRQ;
|
||
|
out:
|
||
|
spin_unlock_irq(&irq_controller_lock);
|
||
|
|
||
|
up(&probe_sem);
|
||
|
|
||
|
return irq_found;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(probe_irq_off);
|
||
|
|
||
|
#ifdef CONFIG_SMP
|
||
|
static void route_irq(struct irqdesc *desc, unsigned int irq, unsigned int cpu)
|
||
|
{
|
||
|
pr_debug("IRQ%u: moving from cpu%u to cpu%u\n", irq, desc->cpu, cpu);
|
||
|
|
||
|
spin_lock_irq(&irq_controller_lock);
|
||
|
desc->cpu = cpu;
|
||
|
desc->chip->set_cpu(desc, irq, cpu);
|
||
|
spin_unlock_irq(&irq_controller_lock);
|
||
|
}
|
||
|
|
||
|
#ifdef CONFIG_PROC_FS
|
||
|
static int
|
||
|
irq_affinity_read_proc(char *page, char **start, off_t off, int count,
|
||
|
int *eof, void *data)
|
||
|
{
|
||
|
struct irqdesc *desc = irq_desc + ((int)data);
|
||
|
int len = cpumask_scnprintf(page, count, desc->affinity);
|
||
|
|
||
|
if (count - len < 2)
|
||
|
return -EINVAL;
|
||
|
page[len++] = '\n';
|
||
|
page[len] = '\0';
|
||
|
|
||
|
return len;
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
irq_affinity_write_proc(struct file *file, const char __user *buffer,
|
||
|
unsigned long count, void *data)
|
||
|
{
|
||
|
unsigned int irq = (unsigned int)data;
|
||
|
struct irqdesc *desc = irq_desc + irq;
|
||
|
cpumask_t affinity, tmp;
|
||
|
int ret = -EIO;
|
||
|
|
||
|
if (!desc->chip->set_cpu)
|
||
|
goto out;
|
||
|
|
||
|
ret = cpumask_parse(buffer, count, affinity);
|
||
|
if (ret)
|
||
|
goto out;
|
||
|
|
||
|
cpus_and(tmp, affinity, cpu_online_map);
|
||
|
if (cpus_empty(tmp)) {
|
||
|
ret = -EINVAL;
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
desc->affinity = affinity;
|
||
|
route_irq(desc, irq, first_cpu(tmp));
|
||
|
ret = count;
|
||
|
|
||
|
out:
|
||
|
return ret;
|
||
|
}
|
||
|
#endif
|
||
|
#endif
|
||
|
|
||
|
void __init init_irq_proc(void)
|
||
|
{
|
||
|
#if defined(CONFIG_SMP) && defined(CONFIG_PROC_FS)
|
||
|
struct proc_dir_entry *dir;
|
||
|
int irq;
|
||
|
|
||
|
dir = proc_mkdir("irq", 0);
|
||
|
if (!dir)
|
||
|
return;
|
||
|
|
||
|
for (irq = 0; irq < NR_IRQS; irq++) {
|
||
|
struct proc_dir_entry *entry;
|
||
|
struct irqdesc *desc;
|
||
|
char name[16];
|
||
|
|
||
|
desc = irq_desc + irq;
|
||
|
memset(name, 0, sizeof(name));
|
||
|
snprintf(name, sizeof(name) - 1, "%u", irq);
|
||
|
|
||
|
desc->procdir = proc_mkdir(name, dir);
|
||
|
if (!desc->procdir)
|
||
|
continue;
|
||
|
|
||
|
entry = create_proc_entry("smp_affinity", 0600, desc->procdir);
|
||
|
if (entry) {
|
||
|
entry->nlink = 1;
|
||
|
entry->data = (void *)irq;
|
||
|
entry->read_proc = irq_affinity_read_proc;
|
||
|
entry->write_proc = irq_affinity_write_proc;
|
||
|
}
|
||
|
}
|
||
|
#endif
|
||
|
}
|
||
|
|
||
|
void __init init_IRQ(void)
|
||
|
{
|
||
|
struct irqdesc *desc;
|
||
|
extern void init_dma(void);
|
||
|
int irq;
|
||
|
|
||
|
#ifdef CONFIG_SMP
|
||
|
bad_irq_desc.affinity = CPU_MASK_ALL;
|
||
|
bad_irq_desc.cpu = smp_processor_id();
|
||
|
#endif
|
||
|
|
||
|
for (irq = 0, desc = irq_desc; irq < NR_IRQS; irq++, desc++) {
|
||
|
*desc = bad_irq_desc;
|
||
|
INIT_LIST_HEAD(&desc->pend);
|
||
|
}
|
||
|
|
||
|
init_arch_irq();
|
||
|
init_dma();
|
||
|
}
|
||
|
|
||
|
static int __init noirqdebug_setup(char *str)
|
||
|
{
|
||
|
noirqdebug = 1;
|
||
|
return 1;
|
||
|
}
|
||
|
|
||
|
__setup("noirqdebug", noirqdebug_setup);
|