2 * linux/arch/alpha/kernel/irq.c
4 * Copyright (C) 1995 Linus Torvalds
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
13 #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>
21 #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>
29 #include <asm/system.h>
31 #include <asm/uaccess.h>
33 volatile unsigned long irq_err_count;
34 DEFINE_PER_CPU(unsigned long, irq_pmi_count);
36 void ack_bad_irq(unsigned int irq)
39 printk(KERN_CRIT "Unexpected IRQ trap at vector %u\n", irq);
43 static char irq_user_affinity[NR_IRQS];
45 int irq_select_affinity(unsigned int irq)
48 int cpu = last_cpu + 1;
50 if (!irq_desc[irq].chip->set_affinity || irq_user_affinity[irq])
53 while (!cpu_possible(cpu) ||
54 !cpumask_test_cpu(cpu, irq_default_affinity))
55 cpu = (cpu < (NR_CPUS-1) ? cpu + 1 : 0);
58 cpumask_copy(irq_desc[irq].affinity, cpumask_of(cpu));
59 irq_desc[irq].chip->set_affinity(irq, cpumask_of(cpu));
62 #endif /* CONFIG_SMP */
65 show_interrupts(struct seq_file *p, void *v)
68 int irq = *(loff_t *) v;
69 struct irqaction * action;
75 for_each_online_cpu(j)
76 seq_printf(p, "CPU%d ", j);
81 if (irq < ACTUAL_NR_IRQS) {
82 raw_spin_lock_irqsave(&irq_desc[irq].lock, flags);
83 action = irq_desc[irq].action;
86 seq_printf(p, "%3d: ", irq);
88 seq_printf(p, "%10u ", kstat_irqs(irq));
90 for_each_online_cpu(j)
91 seq_printf(p, "%10u ", kstat_irqs_cpu(irq, j));
93 seq_printf(p, " %14s", irq_desc[irq].chip->name);
94 seq_printf(p, " %c%s",
95 (action->flags & IRQF_DISABLED)?'+':' ',
98 for (action=action->next; action; action = action->next) {
99 seq_printf(p, ", %c%s",
100 (action->flags & IRQF_DISABLED)?'+':' ',
106 raw_spin_unlock_irqrestore(&irq_desc[irq].lock, flags);
107 } else if (irq == ACTUAL_NR_IRQS) {
109 seq_puts(p, "IPI: ");
110 for_each_online_cpu(j)
111 seq_printf(p, "%10lu ", cpu_data[j].ipi_count);
114 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");
118 seq_printf(p, "ERR: %10lu\n", irq_err_count);
124 * handle_irq handles all normal device IRQ's (the special
125 * SMP cross-CPU interrupts have their own specific
129 #define MAX_ILLEGAL_IRQS 16
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).
141 * 0 return value means that this irq is already being
142 * handled by some other CPU. (or is disabled)
144 static unsigned int illegal_count=0;
146 if ((unsigned) irq > ACTUAL_NR_IRQS && illegal_count < MAX_ILLEGAL_IRQS ) {
149 printk(KERN_CRIT "device_interrupt: invalid interrupt %d\n",
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