arch/mips/pmc-sierra/msp71xx/msp_irq_slp.c

   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 #include <asm/system.h>
  20
  21 #include <msp_slp_int.h>
  22 #include <msp_regs.h>
  23
  24 static inline void unmask_msp_slp_irq(struct irq_data *d)
  25 {
  26         unsigned int irq = d->irq;
  27
  28         /* check for PER interrupt range */
  29         if (irq < MSP_PER_INTBASE)
  30                 *SLP_INT_MSK_REG |= (1 << (irq - MSP_SLP_INTBASE));
  31         else
  32                 *PER_INT_MSK_REG |= (1 << (irq - MSP_PER_INTBASE));
  33 }
  34
  35 static inline void mask_msp_slp_irq(struct irq_data *d)
  36 {
  37         unsigned int irq = d->irq;
  38
  39         /* check for PER interrupt range */
  40         if (irq < MSP_PER_INTBASE)
  41                 *SLP_INT_MSK_REG &= ~(1 << (irq - MSP_SLP_INTBASE));
  42         else
  43                 *PER_INT_MSK_REG &= ~(1 << (irq - MSP_PER_INTBASE));
  44 }
  45
  46 /*
  47  * While we ack the interrupt interrupts are disabled and thus we don't need
  48  * to deal with concurrency issues.  Same for msp_slp_irq_end.
  49  */
  50 static inline void ack_msp_slp_irq(struct irq_data *d)
  51 {
  52         unsigned int irq = d->irq;
  53
  54         /* check for PER interrupt range */
  55         if (irq < MSP_PER_INTBASE)
  56                 *SLP_INT_STS_REG = (1 << (irq - MSP_SLP_INTBASE));
  57         else
  58                 *PER_INT_STS_REG = (1 << (irq - MSP_PER_INTBASE));
  59 }
  60
  61 static struct irq_chip msp_slp_irq_controller = {
  62         .name = "MSP_SLP",
  63         .irq_ack = ack_msp_slp_irq,
  64         .irq_mask = mask_msp_slp_irq,
  65         .irq_unmask = unmask_msp_slp_irq,
  66 };
  67
  68 void __init msp_slp_irq_init(void)
  69 {
  70         int i;
  71
  72         /* Mask/clear interrupts. */
  73         *SLP_INT_MSK_REG = 0x00000000;
  74         *PER_INT_MSK_REG = 0x00000000;
  75         *SLP_INT_STS_REG = 0xFFFFFFFF;
  76         *PER_INT_STS_REG = 0xFFFFFFFF;
  77
  78         /* initialize all the IRQ descriptors */
  79         for (i = MSP_SLP_INTBASE; i < MSP_PER_INTBASE + 32; i++)
  80                 irq_set_chip_and_handler(i, &msp_slp_irq_controller,
  81                                          handle_level_irq);
  82 }
  83
  84 void msp_slp_irq_dispatch(void)
  85 {
  86         u32 pending;
  87         int intbase;
  88
  89         intbase = MSP_SLP_INTBASE;
  90         pending = *SLP_INT_STS_REG & *SLP_INT_MSK_REG;
  91
  92         /* check for PER interrupt */
  93         if (pending == (1 << (MSP_INT_PER - MSP_SLP_INTBASE))) {
  94                 intbase = MSP_PER_INTBASE;
  95                 pending = *PER_INT_STS_REG & *PER_INT_MSK_REG;
  96         }
  97
  98         /* check for spurious interrupt */
  99         if (pending == 0x00000000) {
 100                 printk(KERN_ERR "Spurious %s interrupt?\n",
 101                         (intbase == MSP_SLP_INTBASE) ? "SLP" : "PER");
 102                 return;
 103         }
 104
 105         /* dispatch the irq */
 106         do_IRQ(ffs(pending) + intbase - 1);
 107 }