1. 根目录:
2. arch
3. mips
4. dec
5. ioasic-irq.c

/*
 *	DEC I/O ASIC interrupts.
 *
 *	Copyright (c) 2002, 2003  Maciej W. Rozycki
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 */

#include <linux/init.h>
#include <linux/irq.h>
#include <linux/types.h>

#include <asm/dec/ioasic.h>
#include <asm/dec/ioasic_addrs.h>
#include <asm/dec/ioasic_ints.h>

static int ioasic_irq_base;

static void unmask_ioasic_irq(struct irq_data *d)
{
	u32 simr;

	simr = ioasic_read(IO_REG_SIMR);
	simr |= (1 << (d->irq - ioasic_irq_base));
	ioasic_write(IO_REG_SIMR, simr);
}

static void mask_ioasic_irq(struct irq_data *d)
{
	u32 simr;

	simr = ioasic_read(IO_REG_SIMR);
	simr &= ~(1 << (d->irq - ioasic_irq_base));
	ioasic_write(IO_REG_SIMR, simr);
}

static void ack_ioasic_irq(struct irq_data *d)
{
	mask_ioasic_irq(d);
	fast_iob();
}

static struct irq_chip ioasic_irq_type = {
	.name = "IO-ASIC",
	.irq_ack = ack_ioasic_irq,
	.irq_mask = mask_ioasic_irq,
	.irq_mask_ack = ack_ioasic_irq,
	.irq_unmask = unmask_ioasic_irq,
};

static struct irq_chip ioasic_dma_irq_type = {
	.name = "IO-ASIC-DMA",
	.irq_ack = ack_ioasic_irq,
	.irq_mask = mask_ioasic_irq,
	.irq_mask_ack = ack_ioasic_irq,
	.irq_unmask = unmask_ioasic_irq,
};

void __init init_ioasic_irqs(int base)
{
	int i;

	/* Mask interrupts. */
	ioasic_write(IO_REG_SIMR, 0);
	fast_iob();

	for (i = base; i < base + IO_INR_DMA; i++)
		irq_set_chip_and_handler(i, &ioasic_irq_type,
					 handle_level_irq);
	for (; i < base + IO_IRQ_LINES; i++)
		irq_set_chip(i, &ioasic_dma_irq_type);

	ioasic_irq_base = base;
}