arch/mips/pmcs-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
  20 #include <msp_slp_int.h>
  21 #include <msp_regs.h>
  22
  23 static 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
  34 static 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  */
  49 static 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
  60 static 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
  67 void __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
  83 void 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 }