diff options
Diffstat (limited to 'arch/xtensa/kernel/irq.c')
| -rw-r--r-- | arch/xtensa/kernel/irq.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/arch/xtensa/kernel/irq.c b/arch/xtensa/kernel/irq.c new file mode 100644 index 000000000000..4cbf6d91571f --- /dev/null +++ b/arch/xtensa/kernel/irq.c @@ -0,0 +1,192 @@ +/* + * linux/arch/xtensa/kernel/irq.c + * + * Xtensa built-in interrupt controller and some generic functions copied + * from i386. + * + * Copyright (C) 2002 - 2005 Tensilica, Inc. + * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar + * + * + * Chris Zankel <chris@zankel.net> + * Kevin Chea + * + */ + +#include <linux/module.h> +#include <linux/seq_file.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/kernel_stat.h> + +#include <asm/uaccess.h> +#include <asm/platform.h> + +static void enable_xtensa_irq(unsigned int irq); +static void disable_xtensa_irq(unsigned int irq); +static void mask_and_ack_xtensa(unsigned int irq); +static void end_xtensa_irq(unsigned int irq); + +static unsigned int cached_irq_mask; + +atomic_t irq_err_count; + +/* + * 'what should we do if we get a hw irq event on an illegal vector'. + * each architecture has to answer this themselves. + */ +void ack_bad_irq(unsigned int irq) +{ + printk("unexpected IRQ trap at vector %02x\n", irq); +} + +/* + * do_IRQ handles all normal device IRQ's (the special + * SMP cross-CPU interrupts have their own specific + * handlers). + */ + +unsigned int do_IRQ(int irq, struct pt_regs *regs) +{ + irq_enter(); + +#ifdef CONFIG_DEBUG_STACKOVERFLOW + /* Debugging check for stack overflow: is there less than 1KB free? */ + { + unsigned long sp; + + __asm__ __volatile__ ("mov %0, a1\n" : "=a" (sp)); + sp &= THREAD_SIZE - 1; + + if (unlikely(sp < (sizeof(thread_info) + 1024))) + printk("Stack overflow in do_IRQ: %ld\n", + sp - sizeof(struct thread_info)); + } +#endif + + __do_IRQ(irq, regs); + + irq_exit(); + + return 1; +} + +/* + * Generic, controller-independent functions: + */ + +int show_interrupts(struct seq_file *p, void *v) +{ + int i = *(loff_t *) v, j; + struct irqaction * action; + unsigned long flags; + + if (i == 0) { + seq_printf(p, " "); + for (j=0; j<NR_CPUS; j++) + if (cpu_online(j)) + seq_printf(p, "CPU%d ",j); + seq_putc(p, '\n'); + } + + if (i < NR_IRQS) { + spin_lock_irqsave(&irq_desc[i].lock, flags); + action = irq_desc[i].action; + if (!action) + goto skip; + seq_printf(p, "%3d: ",i); +#ifndef CONFIG_SMP + seq_printf(p, "%10u ", kstat_irqs(i)); +#else + for (j = 0; j < NR_CPUS; j++) + if (cpu_online(j)) + seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]); +#endif + seq_printf(p, " %14s", irq_desc[i].handler->typename); + seq_printf(p, " %s", action->name); + + for (action=action->next; action; action = action->next) + seq_printf(p, ", %s", action->name); + + seq_putc(p, '\n'); +skip: + spin_unlock_irqrestore(&irq_desc[i].lock, flags); + } else if (i == NR_IRQS) { + seq_printf(p, "NMI: "); + for (j = 0; j < NR_CPUS; j++) + if (cpu_online(j)) + seq_printf(p, "%10u ", nmi_count(j)); + seq_putc(p, '\n'); + seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count)); + } + return 0; +} +/* shutdown is same as "disable" */ +#define shutdown_xtensa_irq disable_xtensa_irq + +static unsigned int startup_xtensa_irq(unsigned int irq) +{ + enable_xtensa_irq(irq); + return 0; /* never anything pending */ +} + +static struct hw_interrupt_type xtensa_irq_type = { + "Xtensa-IRQ", + startup_xtensa_irq, + shutdown_xtensa_irq, + enable_xtensa_irq, + disable_xtensa_irq, + mask_and_ack_xtensa, + end_xtensa_irq +}; + +static inline void mask_irq(unsigned int irq) +{ + cached_irq_mask &= ~(1 << irq); + set_sr (cached_irq_mask, INTENABLE); +} + +static inline void unmask_irq(unsigned int irq) +{ + cached_irq_mask |= 1 << irq; + set_sr (cached_irq_mask, INTENABLE); +} + +static void disable_xtensa_irq(unsigned int irq) +{ + unsigned long flags; + local_save_flags(flags); + mask_irq(irq); + local_irq_restore(flags); +} + +static void enable_xtensa_irq(unsigned int irq) +{ + unsigned long flags; + local_save_flags(flags); + unmask_irq(irq); + local_irq_restore(flags); +} + +static void mask_and_ack_xtensa(unsigned int irq) +{ + disable_xtensa_irq(irq); +} + +static void end_xtensa_irq(unsigned int irq) +{ + enable_xtensa_irq(irq); +} + + +void __init init_IRQ(void) +{ + int i; + + for (i=0; i < XTENSA_NR_IRQS; i++) + irq_desc[i].handler = &xtensa_irq_type; + + cached_irq_mask = 0; + + platform_init_irq(); +} |