7066611aeb728acbcc0db88d5bd58f3ec0228885
[linux-2.6.git] / arch / sh / kernel / irq.c
1 /* $Id: irq.c,v 1.20 2004/01/13 05:52:11 kkojima Exp $
2  *
3  * linux/arch/sh/kernel/irq.c
4  *
5  *      Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
6  *
7  *
8  * SuperH version:  Copyright (C) 1999  Niibe Yutaka
9  */
10
11 #include <linux/irq.h>
12 #include <linux/interrupt.h>
13 #include <linux/kernel_stat.h>
14 #include <linux/seq_file.h>
15 #include <asm/irq.h>
16 #include <asm/processor.h>
17 #include <asm/cpu/mmu_context.h>
18
19 /*
20  * 'what should we do if we get a hw irq event on an illegal vector'.
21  * each architecture has to answer this themselves, it doesn't deserve
22  * a generic callback i think.
23  */
24 void ack_bad_irq(unsigned int irq)
25 {
26         printk("unexpected IRQ trap at vector %02x\n", irq);
27 }
28
29 #if defined(CONFIG_PROC_FS)
30 int show_interrupts(struct seq_file *p, void *v)
31 {
32         int i = *(loff_t *) v, j;
33         struct irqaction * action;
34         unsigned long flags;
35
36         if (i == 0) {
37                 seq_puts(p, "           ");
38                 for_each_online_cpu(j)
39                         seq_printf(p, "CPU%d       ",j);
40                 seq_putc(p, '\n');
41         }
42
43         if (i < NR_IRQS) {
44                 spin_lock_irqsave(&irq_desc[i].lock, flags);
45                 action = irq_desc[i].action;
46                 if (!action)
47                         goto unlock;
48                 seq_printf(p, "%3d: ",i);
49                 seq_printf(p, "%10u ", kstat_irqs(i));
50                 seq_printf(p, " %14s", irq_desc[i].chip->typename);
51                 seq_printf(p, "  %s", action->name);
52
53                 for (action=action->next; action; action = action->next)
54                         seq_printf(p, ", %s", action->name);
55                 seq_putc(p, '\n');
56 unlock:
57                 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
58         }
59         return 0;
60 }
61 #endif
62
63 asmlinkage int do_IRQ(unsigned long r4, unsigned long r5,
64                       unsigned long r6, unsigned long r7,
65                       struct pt_regs regs)
66 {
67         int irq = r4;
68
69         irq_enter();
70
71 #ifdef CONFIG_DEBUG_STACKOVERFLOW
72         /* Debugging check for stack overflow: is there less than 1KB free? */
73         {
74                 long sp;
75
76                 __asm__ __volatile__ ("and r15, %0" :
77                                         "=r" (sp) : "0" (THREAD_SIZE - 1));
78
79                 if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {
80                         printk("do_IRQ: stack overflow: %ld\n",
81                                sp - sizeof(struct thread_info));
82                         dump_stack();
83                 }
84         }
85 #endif
86
87 #ifdef CONFIG_CPU_HAS_INTEVT
88         __asm__ __volatile__ (
89 #ifdef CONFIG_CPU_HAS_SR_RB
90                 "stc    r2_bank, %0\n\t"
91 #else
92                 "mov.l  @%1, %0\n\t"
93 #endif
94                 "shlr2  %0\n\t"
95                 "shlr2  %0\n\t"
96                 "shlr   %0\n\t"
97                 "add    #-16, %0\n\t"
98                 : "=z" (irq), "=r" (r4)
99                 : "1" (INTEVT)
100                 : "memory"
101         );
102 #endif
103
104         irq = irq_demux(irq);
105         __do_IRQ(irq, &regs);
106         irq_exit();
107         return 1;
108 }