arch/cris/kernel/irq.c

   1 /*
   2  *
   3  *      linux/arch/cris/kernel/irq.c
   4  *
   5  *      Copyright (c) 2000,2001 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 IRQ's 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  * IRQ's 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/config.h>
  23 #include <linux/module.h>
  24 #include <linux/ptrace.h>
  25 #include <linux/irq.h>
  26
  27 #include <linux/kernel_stat.h>
  28 #include <linux/signal.h>
  29 #include <linux/sched.h>
  30 #include <linux/ioport.h>
  31 #include <linux/interrupt.h>
  32 #include <linux/timex.h>
  33 #include <linux/slab.h>
  34 #include <linux/random.h>
  35 #include <linux/init.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/errno.h>
  38 #include <linux/spinlock.h>
  39
  40 #include <asm/io.h>
  41
  42 void ack_bad_irq(unsigned int irq)
  43 {
  44         printk("unexpected IRQ trap at vector %02x\n", irq);
  45 }
  46
  47 int show_interrupts(struct seq_file *p, void *v)
  48 {
  49         int i = *(loff_t *) v, j;
  50         struct irqaction * action;
  51         unsigned long flags;
  52
  53         if (i == 0) {
  54                 seq_printf(p, "           ");
  55                 for (j=0; j<NR_CPUS; j++)
  56                         if (cpu_online(j))
  57                                 seq_printf(p, "CPU%d       ",j);
  58                 seq_putc(p, '\n');
  59         }
  60
  61         if (i < NR_IRQS) {
  62                 spin_lock_irqsave(&irq_desc[i].lock, flags);
  63                 action = irq_desc[i].action;
  64                 if (!action)
  65                         goto skip;
  66                 seq_printf(p, "%3d: ",i);
  67 #ifndef CONFIG_SMP
  68                 seq_printf(p, "%10u ", kstat_irqs(i));
  69 #else
  70                 for (j = 0; j < NR_CPUS; j++)
  71                         if (cpu_online(j))
  72                                 seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
  73 #endif
  74                 seq_printf(p, " %14s", irq_desc[i].handler->typename);
  75                 seq_printf(p, "  %s", action->name);
  76
  77                 for (action=action->next; action; action = action->next)
  78                         seq_printf(p, ", %s", action->name);
  79
  80                 seq_putc(p, '\n');
  81 skip:
  82                 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
  83         }
  84         return 0;
  85 }
  86
  87
  88 /* called by the assembler IRQ entry functions defined in irq.h
  89  * to dispatch the interrupts to registred handlers
  90  * interrupts are disabled upon entry - depending on if the
  91  * interrupt was registred with SA_INTERRUPT or not, interrupts
  92  * are re-enabled or not.
  93  */
  94
  95 asmlinkage void do_IRQ(int irq, struct pt_regs * regs)
  96 {
  97         unsigned long sp;
  98         irq_enter();
  99         sp = rdsp();
 100         if (unlikely((sp & (PAGE_SIZE - 1)) < (PAGE_SIZE/8))) {
 101                 printk("do_IRQ: stack overflow: %lX\n", sp);
 102                 show_stack(NULL, (unsigned long *)sp);
 103         }
 104         __do_IRQ(irq, regs);
 105         irq_exit();
 106 }
 107
 108 void weird_irq(void)
 109 {
 110         local_irq_disable();
 111         printk("weird irq\n");
 112         while(1);
 113 }
 114