aboutsummaryrefslogtreecommitdiffstats
path: root/arch/mips/kernel/irq.c
blob: 7b845ba9dff4cf565394393dbb1e24f497e5aed4 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Code to handle x86 style IRQs plus some generic interrupt stuff.
 *
 * Copyright (C) 1992 Linus Torvalds
 * Copyright (C) 1994 - 2000 Ralf Baechle
 */
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/random.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/kallsyms.h>
#include <linux/kgdb.h>

#include <asm/atomic.h>
#include <asm/system.h>
#include <asm/uaccess.h>

#ifdef CONFIG_KGDB
int kgdb_early_setup;
#endif

static unsigned long irq_map[NR_IRQS / BITS_PER_LONG];

int allocate_irqno(void)
{
	int irq;

again:
	irq = find_first_zero_bit(irq_map, NR_IRQS);

	if (irq >= NR_IRQS)
		return -ENOSPC;

	if (test_and_set_bit(irq, irq_map))
		goto again;

	return irq;
}

/*
 * Allocate the 16 legacy interrupts for i8259 devices.  This happens early
 * in the kernel initialization so treating allocation failure as BUG() is
 * ok.
 */
void __init alloc_legacy_irqno(void)
{
	int i;

	for (i = 0; i <= 16; i++)
		BUG_ON(test_and_set_bit(i, irq_map));
}

void free_irqno(unsigned int irq)
{
	smp_mb__before_clear_bit();
	clear_bit(irq, irq_map);
	smp_mb__after_clear_bit();
}

/*
 * 'what should we do if we get a hw irq event on an illegal vector'.
 * each architecture has to answer this themselves.
 */
void ack_bad_irq(unsigned int irq)
{
	smtc_im_ack_irq(irq);
	printk("unexpected IRQ # %d\n", irq);
}

atomic_t irq_err_count;

/*
 * Generic, controller-independent functions:
 */

int show_interrupts(struct seq_file *p, void *v)
{
	int i = *(loff_t *) v, j;
	struct irqaction * action;
	unsigned long flags;

	if (i == 0) {
		seq_printf(p, "           ");
		for_each_online_cpu(j)
			seq_printf(p, "CPU%d       ", j);
		seq_putc(p, '\n');
	}

	if (i < NR_IRQS) {
		spin_lock_irqsave(&irq_desc[i].lock, flags);
		action = irq_desc[i].action;
		if (!action)
			goto skip;
		seq_printf(p, "%3d: ", i);
#ifndef CONFIG_SMP
		seq_printf(p, "%10u ", kstat_irqs(i));
#else
		for_each_online_cpu(j)
			seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
#endif
		seq_printf(p, " %14s", irq_desc[i].chip->name);
		seq_printf(p, "  %s", action->name);

		for (action=action->next; action; action = action->next)
			seq_printf(p, ", %s", action->name);

		seq_putc(p, '\n');
skip:
		spin_unlock_irqrestore(&irq_desc[i].lock, flags);
	} else if (i == NR_IRQS) {
		seq_putc(p, '\n');
		seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
	}
	return 0;
}

asmlinkage void spurious_interrupt(void)
{
	atomic_inc(&irq_err_count);
}

void __init init_IRQ(void)
{
	int i;

#ifdef CONFIG_KGDB
	if (kgdb_early_setup)
		return;
#endif

	for (i = 0; i < NR_IRQS; i++)
		set_irq_noprobe(i);

	arch_init_irq();

#ifdef CONFIG_KGDB
	if (!kgdb_early_setup)
		kgdb_early_setup = 1;
#endif
}