diff options
Diffstat (limited to 'arch/alpha/kernel/irq.c')
-rw-r--r-- | arch/alpha/kernel/irq.c | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/arch/alpha/kernel/irq.c b/arch/alpha/kernel/irq.c new file mode 100644 index 000000000..51f2c8654 --- /dev/null +++ b/arch/alpha/kernel/irq.c @@ -0,0 +1,122 @@ +/* + * 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/random.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/io.h> +#include <asm/uaccess.h> + +volatile unsigned long irq_err_count; +DEFINE_PER_CPU(unsigned long, irq_pmi_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) +{ + struct irq_data *data = irq_get_irq_data(irq); + struct irq_chip *chip; + static int last_cpu; + int cpu = last_cpu + 1; + + if (!data) + return 1; + chip = irq_data_get_irq_chip(data); + + if (!chip->irq_set_affinity || irq_user_affinity[irq]) + return 1; + + while (!cpu_possible(cpu) || + !cpumask_test_cpu(cpu, irq_default_affinity)) + cpu = (cpu < (NR_CPUS-1) ? cpu + 1 : 0); + last_cpu = cpu; + + cpumask_copy(data->affinity, cpumask_of(cpu)); + chip->irq_set_affinity(data, cpumask_of(cpu), false); + return 0; +} +#endif /* CONFIG_SMP */ + +int arch_show_interrupts(struct seq_file *p, int prec) +{ + int j; + +#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_puts(p, "PMI: "); + for_each_online_cpu(j) + seq_printf(p, "%10lu ", per_cpu(irq_pmi_count, j)); + seq_puts(p, " Performance Monitoring\n"); + 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; + struct irq_desc *desc = irq_to_desc(irq); + + if (!desc || ((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(); + generic_handle_irq_desc(irq, desc); + irq_exit(); +} |