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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/arch/alpha/kernel/irq.c
3 *
4 * Copyright (C) 1995 Linus Torvalds
5 *
6 * This file contains the code used by various IRQ handling routines:
7 * asking for different IRQ's should be done through these routines
8 * instead of just grabbing them. Thus setups with different IRQ numbers
9 * shouldn't result in any weird surprises, and installing new handlers
10 * should be easier.
11 */
12
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/errno.h>
16#include <linux/kernel_stat.h>
17#include <linux/signal.h>
18#include <linux/sched.h>
19#include <linux/ptrace.h>
20#include <linux/interrupt.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <linux/random.h>
22#include <linux/init.h>
23#include <linux/irq.h>
24#include <linux/proc_fs.h>
25#include <linux/seq_file.h>
26#include <linux/profile.h>
27#include <linux/bitops.h>
28
29#include <asm/system.h>
30#include <asm/io.h>
31#include <asm/uaccess.h>
32
Linus Torvalds1da177e2005-04-16 15:20:36 -070033volatile unsigned long irq_err_count;
Michael Cree65d92062010-08-09 17:20:05 -070034DEFINE_PER_CPU(unsigned long, irq_pmi_count);
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
Ivan Kokshaysky0595bf32006-01-06 00:12:22 -080036void ack_bad_irq(unsigned int irq)
Linus Torvalds1da177e2005-04-16 15:20:36 -070037{
38 irq_err_count++;
39 printk(KERN_CRIT "Unexpected IRQ trap at vector %u\n", irq);
40}
41
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#ifdef CONFIG_SMP
Linus Torvalds1da177e2005-04-16 15:20:36 -070043static char irq_user_affinity[NR_IRQS];
Linus Torvalds1da177e2005-04-16 15:20:36 -070044
Max Krasnyansky18404752008-05-29 11:02:52 -070045int irq_select_affinity(unsigned int irq)
Linus Torvalds1da177e2005-04-16 15:20:36 -070046{
47 static int last_cpu;
48 int cpu = last_cpu + 1;
49
Ingo Molnard1bef4e2006-06-29 02:24:36 -070050 if (!irq_desc[irq].chip->set_affinity || irq_user_affinity[irq])
Ivan Kokshaysky0595bf32006-01-06 00:12:22 -080051 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -070052
Rusty Russelld036e672009-01-01 10:12:26 +103053 while (!cpu_possible(cpu) ||
54 !cpumask_test_cpu(cpu, irq_default_affinity))
Linus Torvalds1da177e2005-04-16 15:20:36 -070055 cpu = (cpu < (NR_CPUS-1) ? cpu + 1 : 0);
56 last_cpu = cpu;
57
Mike Travise65e49d2009-01-12 15:27:13 -080058 cpumask_copy(irq_desc[irq].affinity, cpumask_of(cpu));
Rusty Russell0de26522008-12-13 21:20:26 +103059 irq_desc[irq].chip->set_affinity(irq, cpumask_of(cpu));
Ivan Kokshaysky0595bf32006-01-06 00:12:22 -080060 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070061}
Linus Torvalds1da177e2005-04-16 15:20:36 -070062#endif /* CONFIG_SMP */
63
Linus Torvalds1da177e2005-04-16 15:20:36 -070064int
65show_interrupts(struct seq_file *p, void *v)
66{
Linus Torvalds1da177e2005-04-16 15:20:36 -070067 int j;
Eric Sesterhennc5e3d982006-02-01 03:06:13 -080068 int irq = *(loff_t *) v;
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 struct irqaction * action;
70 unsigned long flags;
71
72#ifdef CONFIG_SMP
Eric Sesterhennc5e3d982006-02-01 03:06:13 -080073 if (irq == 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 seq_puts(p, " ");
Eric Sesterhennc5e3d982006-02-01 03:06:13 -080075 for_each_online_cpu(j)
76 seq_printf(p, "CPU%d ", j);
Linus Torvalds1da177e2005-04-16 15:20:36 -070077 seq_putc(p, '\n');
78 }
79#endif
80
Eric Sesterhennc5e3d982006-02-01 03:06:13 -080081 if (irq < ACTUAL_NR_IRQS) {
Thomas Gleixner239007b2009-11-17 16:46:45 +010082 raw_spin_lock_irqsave(&irq_desc[irq].lock, flags);
Eric Sesterhennc5e3d982006-02-01 03:06:13 -080083 action = irq_desc[irq].action;
Linus Torvalds1da177e2005-04-16 15:20:36 -070084 if (!action)
85 goto unlock;
Eric Sesterhennc5e3d982006-02-01 03:06:13 -080086 seq_printf(p, "%3d: ", irq);
Linus Torvalds1da177e2005-04-16 15:20:36 -070087#ifndef CONFIG_SMP
Eric Sesterhennc5e3d982006-02-01 03:06:13 -080088 seq_printf(p, "%10u ", kstat_irqs(irq));
Linus Torvalds1da177e2005-04-16 15:20:36 -070089#else
Eric Sesterhennc5e3d982006-02-01 03:06:13 -080090 for_each_online_cpu(j)
Andrew Morton4d87c5b2009-01-29 14:29:10 -080091 seq_printf(p, "%10u ", kstat_irqs_cpu(irq, j));
Linus Torvalds1da177e2005-04-16 15:20:36 -070092#endif
Thomas Gleixner8ab12212009-11-30 22:51:31 -050093 seq_printf(p, " %14s", irq_desc[irq].chip->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -070094 seq_printf(p, " %c%s",
Thomas Gleixnerd18eced2006-07-01 19:29:11 -070095 (action->flags & IRQF_DISABLED)?'+':' ',
Linus Torvalds1da177e2005-04-16 15:20:36 -070096 action->name);
97
98 for (action=action->next; action; action = action->next) {
99 seq_printf(p, ", %c%s",
Thomas Gleixnerd18eced2006-07-01 19:29:11 -0700100 (action->flags & IRQF_DISABLED)?'+':' ',
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101 action->name);
102 }
103
104 seq_putc(p, '\n');
105unlock:
Thomas Gleixner239007b2009-11-17 16:46:45 +0100106 raw_spin_unlock_irqrestore(&irq_desc[irq].lock, flags);
Eric Sesterhennc5e3d982006-02-01 03:06:13 -0800107 } else if (irq == ACTUAL_NR_IRQS) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108#ifdef CONFIG_SMP
109 seq_puts(p, "IPI: ");
Eric Sesterhennc5e3d982006-02-01 03:06:13 -0800110 for_each_online_cpu(j)
111 seq_printf(p, "%10lu ", cpu_data[j].ipi_count);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 seq_putc(p, '\n');
113#endif
Michael Cree65d92062010-08-09 17:20:05 -0700114 seq_puts(p, "PMI: ");
115 for_each_online_cpu(j)
116 seq_printf(p, "%10lu ", per_cpu(irq_pmi_count, j));
117 seq_puts(p, " Performance Monitoring\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 seq_printf(p, "ERR: %10lu\n", irq_err_count);
119 }
120 return 0;
121}
122
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123/*
124 * handle_irq handles all normal device IRQ's (the special
125 * SMP cross-CPU interrupts have their own specific
126 * handlers).
127 */
128
129#define MAX_ILLEGAL_IRQS 16
130
131void
Al Viro3dbb8c62006-10-08 14:37:32 +0100132handle_irq(int irq)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133{
134 /*
135 * We ack quickly, we don't want the irq controller
136 * thinking we're snobs just because some other CPU has
137 * disabled global interrupts (we have already done the
138 * INT_ACK cycles, it's too late to try to pretend to the
139 * controller that we aren't taking the interrupt).
140 *
141 * 0 return value means that this irq is already being
142 * handled by some other CPU. (or is disabled)
143 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144 static unsigned int illegal_count=0;
145
146 if ((unsigned) irq > ACTUAL_NR_IRQS && illegal_count < MAX_ILLEGAL_IRQS ) {
147 irq_err_count++;
148 illegal_count++;
149 printk(KERN_CRIT "device_interrupt: invalid interrupt %d\n",
150 irq);
151 return;
152 }
153
154 irq_enter();
Ivan Kokshayskyeff2c2f2006-03-09 17:33:37 -0800155 /*
156 * __do_IRQ() must be called with IPL_MAX. Note that we do not
157 * explicitly enable interrupts afterwards - some MILO PALcode
158 * (namely LX164 one) seems to have severe problems with RTI
159 * at IPL 0.
160 */
Ivan Kokshaysky0595bf32006-01-06 00:12:22 -0800161 local_irq_disable();
Al Viro8774cb82006-10-07 14:17:31 +0100162 __do_IRQ(irq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163 irq_exit();
164}