| /* |
| * linux/arch/alpha/kernel/irq.c |
| * |
| * Copyright (C) 1995 Linus Torvalds |
| * |
| * This file contains the code used by various IRQ handling routines: |
| * asking for different IRQ's should be done through these routines |
| * instead of just grabbing them. Thus setups with different IRQ numbers |
| * shouldn't result in any weird surprises, and installing new handlers |
| * should be easier. |
| */ |
| |
| #include <linux/config.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/errno.h> |
| #include <linux/kernel_stat.h> |
| #include <linux/signal.h> |
| #include <linux/sched.h> |
| #include <linux/ptrace.h> |
| #include <linux/interrupt.h> |
| #include <linux/slab.h> |
| #include <linux/random.h> |
| #include <linux/init.h> |
| #include <linux/irq.h> |
| #include <linux/proc_fs.h> |
| #include <linux/seq_file.h> |
| #include <linux/profile.h> |
| #include <linux/bitops.h> |
| |
| #include <asm/system.h> |
| #include <asm/io.h> |
| #include <asm/uaccess.h> |
| |
| volatile unsigned long irq_err_count; |
| |
| void ack_bad_irq(unsigned int irq) |
| { |
| irq_err_count++; |
| printk(KERN_CRIT "Unexpected IRQ trap at vector %u\n", irq); |
| } |
| |
| #ifdef CONFIG_SMP |
| static char irq_user_affinity[NR_IRQS]; |
| |
| int |
| select_smp_affinity(unsigned int irq) |
| { |
| static int last_cpu; |
| int cpu = last_cpu + 1; |
| |
| if (!irq_desc[irq].chip->set_affinity || irq_user_affinity[irq]) |
| return 1; |
| |
| while (!cpu_possible(cpu)) |
| cpu = (cpu < (NR_CPUS-1) ? cpu + 1 : 0); |
| last_cpu = cpu; |
| |
| irq_desc[irq].affinity = cpumask_of_cpu(cpu); |
| irq_desc[irq].chip->set_affinity(irq, cpumask_of_cpu(cpu)); |
| return 0; |
| } |
| #endif /* CONFIG_SMP */ |
| |
| int |
| show_interrupts(struct seq_file *p, void *v) |
| { |
| #ifdef CONFIG_SMP |
| int j; |
| #endif |
| int irq = *(loff_t *) v; |
| struct irqaction * action; |
| unsigned long flags; |
| |
| #ifdef CONFIG_SMP |
| if (irq == 0) { |
| seq_puts(p, " "); |
| for_each_online_cpu(j) |
| seq_printf(p, "CPU%d ", j); |
| seq_putc(p, '\n'); |
| } |
| #endif |
| |
| if (irq < ACTUAL_NR_IRQS) { |
| spin_lock_irqsave(&irq_desc[irq].lock, flags); |
| action = irq_desc[irq].action; |
| if (!action) |
| goto unlock; |
| seq_printf(p, "%3d: ", irq); |
| #ifndef CONFIG_SMP |
| seq_printf(p, "%10u ", kstat_irqs(irq)); |
| #else |
| for_each_online_cpu(j) |
| seq_printf(p, "%10u ", kstat_cpu(j).irqs[irq]); |
| #endif |
| seq_printf(p, " %14s", irq_desc[irq].chip->typename); |
| seq_printf(p, " %c%s", |
| (action->flags & SA_INTERRUPT)?'+':' ', |
| action->name); |
| |
| for (action=action->next; action; action = action->next) { |
| seq_printf(p, ", %c%s", |
| (action->flags & SA_INTERRUPT)?'+':' ', |
| action->name); |
| } |
| |
| seq_putc(p, '\n'); |
| unlock: |
| spin_unlock_irqrestore(&irq_desc[irq].lock, flags); |
| } else if (irq == ACTUAL_NR_IRQS) { |
| #ifdef CONFIG_SMP |
| seq_puts(p, "IPI: "); |
| for_each_online_cpu(j) |
| seq_printf(p, "%10lu ", cpu_data[j].ipi_count); |
| seq_putc(p, '\n'); |
| #endif |
| seq_printf(p, "ERR: %10lu\n", irq_err_count); |
| } |
| return 0; |
| } |
| |
| /* |
| * handle_irq handles all normal device IRQ's (the special |
| * SMP cross-CPU interrupts have their own specific |
| * handlers). |
| */ |
| |
| #define MAX_ILLEGAL_IRQS 16 |
| |
| void |
| handle_irq(int irq, struct pt_regs * regs) |
| { |
| /* |
| * We ack quickly, we don't want the irq controller |
| * thinking we're snobs just because some other CPU has |
| * disabled global interrupts (we have already done the |
| * INT_ACK cycles, it's too late to try to pretend to the |
| * controller that we aren't taking the interrupt). |
| * |
| * 0 return value means that this irq is already being |
| * handled by some other CPU. (or is disabled) |
| */ |
| static unsigned int illegal_count=0; |
| |
| if ((unsigned) irq > ACTUAL_NR_IRQS && illegal_count < MAX_ILLEGAL_IRQS ) { |
| irq_err_count++; |
| illegal_count++; |
| printk(KERN_CRIT "device_interrupt: invalid interrupt %d\n", |
| irq); |
| return; |
| } |
| |
| irq_enter(); |
| /* |
| * __do_IRQ() must be called with IPL_MAX. Note that we do not |
| * explicitly enable interrupts afterwards - some MILO PALcode |
| * (namely LX164 one) seems to have severe problems with RTI |
| * at IPL 0. |
| */ |
| local_irq_disable(); |
| __do_IRQ(irq, regs); |
| irq_exit(); |
| } |