diff options
Diffstat (limited to 'arch/alpha/kernel/irq.c')
| -rw-r--r-- | arch/alpha/kernel/irq.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/arch/alpha/kernel/irq.c b/arch/alpha/kernel/irq.c new file mode 100644 index 0000000..c626a82 --- /dev/null +++ b/arch/alpha/kernel/irq.c @@ -0,0 +1,161 @@ +/* + * 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/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 irq_select_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_isset(cpu, irq_default_affinity)) + 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 & IRQF_DISABLED)?'+':' ', + action->name); + + for (action=action->next; action; action = action->next) { + seq_printf(p, ", %c%s", + (action->flags & IRQF_DISABLED)?'+':' ', + 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) +{ + /* + * 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); + irq_exit(); +} |
