msp_irq_slp.c

Go to the documentation of this file.

/*
 * This file define the irq handler for MSP SLM subsystem interrupts.
 *
 * Copyright 2005-2006 PMC-Sierra, Inc, derived from irq_cpu.c
 * Author: Andrew Hughes, [email protected]
 *
 * 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/interrupt.h>
#include <linux/kernel.h>
#include <linux/bitops.h>

#include <asm/mipsregs.h>

#include <msp_slp_int.h>
#include <msp_regs.h>

static inline void unmask_msp_slp_irq(struct irq_data *d)
{
    unsigned int irq = d->irq;

    /* check for PER interrupt range */
    if (irq < MSP_PER_INTBASE)
        *SLP_INT_MSK_REG |= (1 << (irq - MSP_SLP_INTBASE));
    else
        *PER_INT_MSK_REG |= (1 << (irq - MSP_PER_INTBASE));
}

static inline void mask_msp_slp_irq(struct irq_data *d)
{
    unsigned int irq = d->irq;

    /* check for PER interrupt range */
    if (irq < MSP_PER_INTBASE)
        *SLP_INT_MSK_REG &= ~(1 << (irq - MSP_SLP_INTBASE));
    else
        *PER_INT_MSK_REG &= ~(1 << (irq - MSP_PER_INTBASE));
}

/*
 * While we ack the interrupt interrupts are disabled and thus we don't need
 * to deal with concurrency issues.  Same for msp_slp_irq_end.
 */
static inline void ack_msp_slp_irq(struct irq_data *d)
{
    unsigned int irq = d->irq;

    /* check for PER interrupt range */
    if (irq < MSP_PER_INTBASE)
        *SLP_INT_STS_REG = (1 << (irq - MSP_SLP_INTBASE));
    else
        *PER_INT_STS_REG = (1 << (irq - MSP_PER_INTBASE));
}

static struct irq_chip msp_slp_irq_controller = {
    .name = "MSP_SLP",
    .irq_ack = ack_msp_slp_irq,
    .irq_mask = mask_msp_slp_irq,
    .irq_unmask = unmask_msp_slp_irq,
};

void __init msp_slp_irq_init(void)
{
    int i;

    /* Mask/clear interrupts. */
    *SLP_INT_MSK_REG = 0x00000000;
    *PER_INT_MSK_REG = 0x00000000;
    *SLP_INT_STS_REG = 0xFFFFFFFF;
    *PER_INT_STS_REG = 0xFFFFFFFF;

    /* initialize all the IRQ descriptors */
    for (i = MSP_SLP_INTBASE; i < MSP_PER_INTBASE + 32; i++)
        irq_set_chip_and_handler(i, &msp_slp_irq_controller,
                     handle_level_irq);
}

void msp_slp_irq_dispatch(void)
{
    u32 pending;
    int intbase;

    intbase = MSP_SLP_INTBASE;
    pending = *SLP_INT_STS_REG & *SLP_INT_MSK_REG;

    /* check for PER interrupt */
    if (pending == (1 << (MSP_INT_PER - MSP_SLP_INTBASE))) {
        intbase = MSP_PER_INTBASE;
        pending = *PER_INT_STS_REG & *PER_INT_MSK_REG;
    }

    /* check for spurious interrupt */
    if (pending == 0x00000000) {
        printk(KERN_ERR "Spurious %s interrupt?\n",
            (intbase == MSP_SLP_INTBASE) ? "SLP" : "PER");
        return;
    }

    /* dispatch the irq */
    do_IRQ(ffs(pending) + intbase - 1);
}