blob: 4cbf6d91571f47aa465be4d3ddeb94e733fe709e [file] [log] [blame]
/*
* 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();
}