2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * Code to handle x86 style IRQs plus some generic interrupt stuff.
8 * Copyright (C) 1992 Linus Torvalds
9 * Copyright (C) 1994 - 2000 Ralf Baechle
11 #include <linux/kernel.h>
12 #include <linux/delay.h>
13 #include <linux/init.h>
14 #include <linux/interrupt.h>
15 #include <linux/kernel_stat.h>
16 #include <linux/module.h>
17 #include <linux/proc_fs.h>
18 #include <linux/slab.h>
20 #include <linux/random.h>
21 #include <linux/sched.h>
22 #include <linux/seq_file.h>
23 #include <linux/kallsyms.h>
24 #include <linux/kgdb.h>
26 #include <asm/atomic.h>
27 #include <asm/system.h>
28 #include <asm/uaccess.h>
34 static unsigned long irq_map[NR_IRQS / BITS_PER_LONG];
36 int allocate_irqno(void)
41 irq = find_first_zero_bit(irq_map, NR_IRQS);
46 if (test_and_set_bit(irq, irq_map))
53 * Allocate the 16 legacy interrupts for i8259 devices. This happens early
54 * in the kernel initialization so treating allocation failure as BUG() is
57 void __init alloc_legacy_irqno(void)
61 for (i = 0; i <= 16; i++)
62 BUG_ON(test_and_set_bit(i, irq_map));
65 void free_irqno(unsigned int irq)
67 smp_mb__before_clear_bit();
68 clear_bit(irq, irq_map);
69 smp_mb__after_clear_bit();
73 * 'what should we do if we get a hw irq event on an illegal vector'.
74 * each architecture has to answer this themselves.
76 void ack_bad_irq(unsigned int irq)
79 printk("unexpected IRQ # %d\n", irq);
82 atomic_t irq_err_count;
85 * Generic, controller-independent functions:
88 int show_interrupts(struct seq_file *p, void *v)
90 int i = *(loff_t *) v, j;
91 struct irqaction * action;
96 for_each_online_cpu(j)
97 seq_printf(p, "CPU%d ", j);
102 spin_lock_irqsave(&irq_desc[i].lock, flags);
103 action = irq_desc[i].action;
106 seq_printf(p, "%3d: ", i);
108 seq_printf(p, "%10u ", kstat_irqs(i));
110 for_each_online_cpu(j)
111 seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
113 seq_printf(p, " %14s", irq_desc[i].chip->name);
114 seq_printf(p, " %s", action->name);
116 for (action=action->next; action; action = action->next)
117 seq_printf(p, ", %s", action->name);
121 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
122 } else if (i == NR_IRQS) {
124 seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
129 asmlinkage void spurious_interrupt(void)
131 atomic_inc(&irq_err_count);
134 void __init init_IRQ(void)
139 if (kgdb_early_setup)
143 for (i = 0; i < NR_IRQS; i++)
149 if (!kgdb_early_setup)
150 kgdb_early_setup = 1;