LXR linux/arch/mips/pmcs-msp71xx/msp_irq

   1/*
   2 * This file define the irq handler for MSP SLM subsystem interrupts.
   3 *
   4 * Copyright 2005-2006 PMC-Sierra, Inc, derived from irq_cpu.c
   5 * Author: Andrew Hughes, Andrew_Hughes@pmc-sierra.com
   6 *
   7 * This program is free software; you can redistribute  it and/or modify it
   8 * under  the terms of  the GNU General  Public License as published by the
   9 * Free Software Foundation;  either version 2 of the  License, or (at your
  10 * option) any later version.
  11 */
  12
  13#include <linux/init.h>
  14#include <linux/interrupt.h>
  15#include <linux/kernel.h>
  16#include <linux/bitops.h>
  17
  18#include <asm/mipsregs.h>
  19
  20#include <msp_slp_int.h>
  21#include <msp_regs.h>
  22
  23static inline void unmask_msp_slp_irq(struct irq_data *d)
  24{
  25        unsigned int irq = d->irq;
  26
  27        /* check for PER interrupt range */
  28        if (irq < MSP_PER_INTBASE)
  29                *SLP_INT_MSK_REG |= (1 << (irq - MSP_SLP_INTBASE));
  30        else
  31                *PER_INT_MSK_REG |= (1 << (irq - MSP_PER_INTBASE));
  32}
  33
  34static inline void mask_msp_slp_irq(struct irq_data *d)
  35{
  36        unsigned int irq = d->irq;
  37
  38        /* check for PER interrupt range */
  39        if (irq < MSP_PER_INTBASE)
  40                *SLP_INT_MSK_REG &= ~(1 << (irq - MSP_SLP_INTBASE));
  41        else
  42                *PER_INT_MSK_REG &= ~(1 << (irq - MSP_PER_INTBASE));
  43}
  44
  45/*
  46 * While we ack the interrupt interrupts are disabled and thus we don't need
  47 * to deal with concurrency issues.  Same for msp_slp_irq_end.
  48 */
  49static inline void ack_msp_slp_irq(struct irq_data *d)
  50{
  51        unsigned int irq = d->irq;
  52
  53        /* check for PER interrupt range */
  54        if (irq < MSP_PER_INTBASE)
  55                *SLP_INT_STS_REG = (1 << (irq - MSP_SLP_INTBASE));
  56        else
  57                *PER_INT_STS_REG = (1 << (irq - MSP_PER_INTBASE));
  58}
  59
  60static struct irq_chip msp_slp_irq_controller = {
  61        .name = "MSP_SLP",
  62        .irq_ack = ack_msp_slp_irq,
  63        .irq_mask = mask_msp_slp_irq,
  64        .irq_unmask = unmask_msp_slp_irq,
  65};
  66
  67void __init msp_slp_irq_init(void)
  68{
  69        int i;
  70
  71        /* Mask/clear interrupts. */
  72        *SLP_INT_MSK_REG = 0x00000000;
  73        *PER_INT_MSK_REG = 0x00000000;
  74        *SLP_INT_STS_REG = 0xFFFFFFFF;
  75        *PER_INT_STS_REG = 0xFFFFFFFF;
  76
  77        /* initialize all the IRQ descriptors */
  78        for (i = MSP_SLP_INTBASE; i < MSP_PER_INTBASE + 32; i++)
  79                irq_set_chip_and_handler(i, &msp_slp_irq_controller,
  80                                         handle_level_irq);
  81}
  82
  83void msp_slp_irq_dispatch(void)
  84{
  85        u32 pending;
  86        int intbase;
  87
  88        intbase = MSP_SLP_INTBASE;
  89        pending = *SLP_INT_STS_REG & *SLP_INT_MSK_REG;
  90
  91        /* check for PER interrupt */
  92        if (pending == (1 << (MSP_INT_PER - MSP_SLP_INTBASE))) {
  93                intbase = MSP_PER_INTBASE;
  94                pending = *PER_INT_STS_REG & *PER_INT_MSK_REG;
  95        }
  96
  97        /* check for spurious interrupt */
  98        if (pending == 0x00000000) {
  99                printk(KERN_ERR "Spurious %s interrupt?\n",
 100                        (intbase == MSP_SLP_INTBASE) ? "SLP" : "PER");
 101                return;
 102        }
 103
 104        /* dispatch the irq */
 105        do_IRQ(ffs(pending) + intbase - 1);
 106}
 107