ints.c

arm平台上的uclinux系统全部源代码

/*
 * linux/arch/i$(ARCH)/kernel/ints.c -- general interrupt handling code
 *
 * Cloned from Linux/m68k.
 *
 * No original Copyright holder listed,
 * Probabily original (C) Roman Zippel (assigned DJD, 1999)
 *
 * Copyright 1999 D. Jeff Dionne 1999, <[e-mail]>
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file COPYING in the main directory of this archive
 * for more details.
 */

#include <linux/types.h>
#include <linux/sched.h>
#include <linux/kernel_stat.h>
#include <linux/errno.h>

#include <asm/system.h>
#include <asm/irq.h>
#include <asm/traps.h>
#include <asm/page.h>
#include <asm/machdep.h>

/* table for system interrupt handlers */
static irq_handler_t irq_list[SYS_IRQS];

static const char *default_names[SYS_IRQS] = {
	"spurious int", "int1 handler", "int2 handler", "int3 handler",
	"int4 handler", "int5 handler", "int6 handler", "int7 handler"
};

/* The number of spurious interrupts */
volatile unsigned int num_spurious;

#define NUM_IRQ_NODES 16
static irq_node_t nodes[NUM_IRQ_NODES];

/*
 * void init_IRQ(void)
 *
 * Parameters:	None
 *
 * Returns:	Nothing
 *
 * This function should be called during kernel startup to initialize
 * the IRQ handling routines.
 */

void init_IRQ(void)
{
	int i;

	for (i = 0; i < SYS_IRQS; i++) {
		if (mach_default_handler)
			irq_list[i].handler = (*mach_default_handler)[i];
		else
			irq_list[i].handler = NULL;
			irq_list[i].flags   = IRQ_FLG_STD;
			irq_list[i].dev_id  = NULL;
			irq_list[i].devname = default_names[i];
	}

	for (i = 0; i < NUM_IRQ_NODES; i++)
		nodes[i].handler = NULL;

	mach_init_IRQ ();
}

irq_node_t *new_irq_node(void)
{
	irq_node_t *node;
	short i;

	for (node = nodes, i = NUM_IRQ_NODES-1; i >= 0; node++, i--)
		if (!node->handler)
			return node;

	printk ("new_irq_node: out of nodes\n");
	return NULL;
}

int request_irq(unsigned int irq, void (*handler)(int, void *, struct pt_regs *),
                unsigned long flags, const char *devname, void *dev_id)
{
	if (irq & IRQ_MACHSPEC)
		return mach_request_irq(IRQ_IDX(irq), handler, flags, devname, dev_id);

	if (irq < IRQ1 || irq > IRQ7) {
		printk("%s: Incorrect IRQ %d from %s\n", __FUNCTION__, irq, devname);
		return -ENXIO;
	}

	if (!(irq_list[irq].flags & IRQ_FLG_STD)) {
		if (irq_list[irq].flags & IRQ_FLG_LOCK) {
			printk("%s: IRQ %d from %s is not replaceable\n",
			       __FUNCTION__, irq, irq_list[irq].devname);
			return -EBUSY;
		}
		if (flags & IRQ_FLG_REPLACE) {
			printk("%s: %s can't replace IRQ %d from %s\n",
			       __FUNCTION__, devname, irq, irq_list[irq].devname);
			return -EBUSY;
		}
	}
	irq_list[irq].handler = handler;
	irq_list[irq].flags   = flags;
	irq_list[irq].dev_id  = dev_id;
	irq_list[irq].devname = devname;
	return 0;
}

void free_irq(unsigned int irq, void *dev_id)
{
	if (irq & IRQ_MACHSPEC) {
		mach_free_irq(IRQ_IDX(irq), dev_id);
		return;
	}

	if (irq < IRQ1 || irq > IRQ7) {
		printk("%s: Incorrect IRQ %d\n", __FUNCTION__, irq);
		return;
	}

	if (irq_list[irq].dev_id != dev_id)
		printk("%s: Removing probably wrong IRQ %d from %s\n",
		       __FUNCTION__, irq, irq_list[irq].devname);

	if (mach_default_handler)
		irq_list[irq].handler = (*mach_default_handler)[irq];
	else
		irq_list[irq].handler = NULL;
	irq_list[irq].flags   = IRQ_FLG_STD;
	irq_list[irq].dev_id  = NULL;
	irq_list[irq].devname = default_names[irq];
}

/*
 * Do we need these probe functions on the m68k?
 */
unsigned long probe_irq_on (void)
{
	return 0;
}

int probe_irq_off (unsigned long irqs)
{
	return 0;
}

void enable_irq(unsigned int irq)
{
	if ((irq & IRQ_MACHSPEC) && mach_enable_irq)
		mach_enable_irq(IRQ_IDX(irq));
}

void disable_irq(unsigned int irq)
{
	if ((irq & IRQ_MACHSPEC) && mach_disable_irq)
		mach_disable_irq(IRQ_IDX(irq));
}

asmlinkage void process_int(unsigned long vec, struct pt_regs *fp)
{
	/* give the machine specific code a crack at it first */
	if (mach_process_int)
		if (!mach_process_int(vec, fp))
			return;

	if (vec < VEC_SPUR || vec > VEC_INT7)
		panic("No interrupt handler for vector %ld\n", vec);

	vec -= VEC_SPUR;
	kstat.interrupts[vec]++;
	if (irq_list[vec].handler)
		irq_list[vec].handler(vec, irq_list[vec].dev_id, fp);
	else
		panic("No interrupt handler for autovector %ld\n", vec);
}

int get_irq_list(char *buf)
{
	int i, len = 0;

	/* autovector interrupts */
	for (i = 0; i < SYS_IRQS; i++) {
		if (irq_list[i].handler) {
			len += sprintf(buf+len, "auto %2d: %10u ", i,
			               i ? kstat.interrupts[i] : num_spurious);
			if (irq_list[i].flags & IRQ_FLG_LOCK)
				len += sprintf(buf+len, "L ");
			else
				len += sprintf(buf+len, "  ");
			len += sprintf(buf+len, "%s\n", irq_list[i].devname);
		}
	}

	if (mach_get_irq_list)
		len += mach_get_irq_list(buf+len);
	return len;
}