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 40int show_interrupts(struct seq_file *p, void *v) 41{ 42 int i = *(loff_t *) v, j; 43 struct irqaction * action; 44 unsigned long flags; 45 46 if (i == 0) { 47 seq_printf(p, " "); 48 for_each_online_cpu(j) 49 seq_printf(p, "CPU%d ",j); 50 seq_putc(p, '\n'); 51 } 52 53 if (i < NR_IRQS) { 54 raw_spin_lock_irqsave(&irq_desc[i].lock, flags); 55 action = irq_desc[i].action; 56 if (!action) 57 goto skip; 58 seq_printf(p, "%3d: ",i); 59#ifndef CONFIG_SMP 60 seq_printf(p, "%10u ", kstat_irqs(i)); 61#else 62 for_each_online_cpu(j) 63 seq_printf(p, "%10u ", kstat_irqs_cpu(i, j)); 64#endif 65 seq_printf(p, " %14s", irq_desc[i].chip->name); 66 seq_printf(p, " %s", action->name); 67 68 for (action=action->next; action; action = action->next) 69 seq_printf(p, ", %s", action->name); 70 71 seq_putc(p, '\n'); 72skip: 73 raw_spin_unlock_irqrestore(&irq_desc[i].lock, flags); 74 } 75 return 0; 76} 77 78 79/* called by the assembler IRQ entry functions defined in irq.h 80 * to dispatch the interrupts to registered handlers 81 * interrupts are disabled upon entry - depending on if the 82 * interrupt was registered with IRQF_DISABLED or not, interrupts 83 * are re-enabled or not. 84 */ 85 86asmlinkage void do_IRQ(int irq, struct pt_regs * regs) 87{ 88 unsigned long sp; 89 struct pt_regs *old_regs = set_irq_regs(regs); 90 irq_enter(); 91 sp = rdsp(); 92 if (unlikely((sp & (PAGE_SIZE - 1)) < (PAGE_SIZE/8))) { 93 printk("do_IRQ: stack overflow: %lX\n", sp); 94 show_stack(NULL, (unsigned long *)sp); 95 } 96 __do_IRQ(irq); 97 irq_exit(); 98 set_irq_regs(old_regs); 99} 100 101void weird_irq(void) 102{ 103 local_irq_disable(); 104 printk("weird irq\n"); 105 while(1); 106} 107