LXR linux/arch/cris/kernel/irq.c

   1/*
   2 *
   3 *      linux/arch/cris/kernel/irq.c
   4 *
   5 *      Copyright (c) 2000,2007 Axis Communications AB
   6 *
   7 *      Authors: Bjorn Wesen (bjornw@axis.com)
   8 *
   9 * This file contains the code used by various IRQ handling routines:
  10 * asking for different IRQs should be done through these routines
  11 * instead of just grabbing them. Thus setups with different IRQ numbers
  12 * shouldn't result in any weird surprises, and installing new handlers
  13 * should be easier.
  14 *
  15 */
  16
  17/*
  18 * IRQs are in fact implemented a bit like signal handlers for the kernel.
  19 * Naturally it's not a 1:1 relation, but there are similarities.
  20 */
  21
  22#include <linux/module.h>
  23#include <linux/ptrace.h>
  24#include <linux/irq.h>
  25
  26#include <linux/kernel_stat.h>
  27#include <linux/signal.h>
  28#include <linux/sched.h>
  29#include <linux/ioport.h>
  30#include <linux/interrupt.h>
  31#include <linux/timex.h>
  32#include <linux/slab.h>
  33#include <linux/random.h>
  34#include <linux/init.h>
  35#include <linux/seq_file.h>
  36#include <linux/errno.h>
  37#include <linux/spinlock.h>
  38
  39#include <asm/io.h>
  40
  41int show_interrupts(struct seq_file *p, void *v)
  42{
  43        int i = *(loff_t *) v, j;
  44        struct irqaction * action;
  45        unsigned long flags;
  46
  47        if (i == 0) {
  48                seq_printf(p, "           ");
  49                for_each_online_cpu(j)
  50                        seq_printf(p, "CPU%d       ",j);
  51                seq_putc(p, '\n');
  52        }
  53
  54        if (i < NR_IRQS) {
  55                spin_lock_irqsave(&irq_desc[i].lock, flags);
  56                action = irq_desc[i].action;
  57                if (!action)
  58                        goto skip;
  59                seq_printf(p, "%3d: ",i);
  60#ifndef CONFIG_SMP
  61                seq_printf(p, "%10u ", kstat_irqs(i));
  62#else
  63                for_each_online_cpu(j)
  64                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
  65#endif
  66                seq_printf(p, " %14s", irq_desc[i].chip->typename);
  67                seq_printf(p, "  %s", action->name);
  68
  69                for (action=action->next; action; action = action->next)
  70                        seq_printf(p, ", %s", action->name);
  71
  72                seq_putc(p, '\n');
  73skip:
  74                spin_unlock_irqrestore(&irq_desc[i].lock, flags);
  75        }
  76        return 0;
  77}
  78
  79
  80/* called by the assembler IRQ entry functions defined in irq.h
  81 * to dispatch the interrupts to registered handlers
  82 * interrupts are disabled upon entry - depending on if the
  83 * interrupt was registered with IRQF_DISABLED or not, interrupts
  84 * are re-enabled or not.
  85 */
  86
  87asmlinkage void do_IRQ(int irq, struct pt_regs * regs)
  88{
  89        unsigned long sp;
  90        struct pt_regs *old_regs = set_irq_regs(regs);
  91        irq_enter();
  92        sp = rdsp();
  93        if (unlikely((sp & (PAGE_SIZE - 1)) < (PAGE_SIZE/8))) {
  94                printk("do_IRQ: stack overflow: %lX\n", sp);
  95                show_stack(NULL, (unsigned long *)sp);
  96        }
  97        __do_IRQ(irq);
  98        irq_exit();
  99        set_irq_regs(old_regs);
 100}
 101
 102void weird_irq(void)
 103{
 104        local_irq_disable();
 105        printk("weird irq\n");
 106        while(1);
 107}
 108
 109