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/random.h>
  33 #include <linux/init.h>
  34 #include <linux/seq_file.h>
  35 #include <linux/errno.h>
  36 #include <linux/spinlock.h>
  37
  38 #include <asm/io.h>
  39
  40 /* called by the assembler IRQ entry functions defined in irq.h
  41  * to dispatch the interrupts to registered handlers
  42  * interrupts are disabled upon entry - depending on if the
  43  * interrupt was registered with IRQF_DISABLED or not, interrupts
  44  * are re-enabled or not.
  45  */
  46
  47 asmlinkage void do_IRQ(int irq, struct pt_regs * regs)
  48 {
  49         unsigned long sp;
  50         struct pt_regs *old_regs = set_irq_regs(regs);
  51         irq_enter();
  52         sp = rdsp();
  53         if (unlikely((sp & (PAGE_SIZE - 1)) < (PAGE_SIZE/8))) {
  54                 printk("do_IRQ: stack overflow: %lX\n", sp);
  55                 show_stack(NULL, (unsigned long *)sp);
  56         }
  57         generic_handle_irq(irq);
  58         irq_exit();
  59         set_irq_regs(old_regs);
  60 }
  61
  62 void weird_irq(void)
  63 {
  64         local_irq_disable();
  65         printk("weird irq\n");
  66         while(1);
  67 }
  68