arch/mips/ddb5xxx/ddb5477/irq_5477.c

   1 /*
   2  * Copyright 2001 MontaVista Software Inc.
   3  * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
   4  *
   5  *  arch/mips/ddb5xxx/ddb5477/irq_5477.c
   6  *     This file defines the irq handler for Vrc5477.
   7  *
   8  * This program is free software; you can redistribute  it and/or modify it
   9  * under  the terms of  the GNU General  Public License as published by the
  10  * Free Software Foundation;  either version 2 of the  License, or (at your
  11  * option) any later version.
  12  *
  13  */
  14
  15 /*
  16  * Vrc5477 defines 32 IRQs.
  17  *
  18  * This file exports one function:
  19  *      vrc5477_irq_init(u32 irq_base);
  20  */
  21
  22 #include <linux/interrupt.h>
  23 #include <linux/types.h>
  24 #include <linux/ptrace.h>
  25
  26 #include <asm/debug.h>
  27
  28 #include <asm/ddb5xxx/ddb5xxx.h>
  29
  30 /* number of total irqs supported by Vrc5477 */
  31 #define NUM_5477_IRQ            32
  32
  33 static int vrc5477_irq_base = -1;
  34
  35
  36 static void
  37 vrc5477_irq_enable(unsigned int irq)
  38 {
  39         db_assert(vrc5477_irq_base != -1);
  40         db_assert(irq >= vrc5477_irq_base);
  41         db_assert(irq < vrc5477_irq_base+ NUM_5477_IRQ);
  42
  43         ll_vrc5477_irq_enable(irq - vrc5477_irq_base);
  44 }
  45
  46 static void
  47 vrc5477_irq_disable(unsigned int irq)
  48 {
  49         db_assert(vrc5477_irq_base != -1);
  50         db_assert(irq >= vrc5477_irq_base);
  51         db_assert(irq < vrc5477_irq_base + NUM_5477_IRQ);
  52
  53         ll_vrc5477_irq_disable(irq - vrc5477_irq_base);
  54 }
  55
  56 static void
  57 vrc5477_irq_ack(unsigned int irq)
  58 {
  59         db_assert(vrc5477_irq_base != -1);
  60         db_assert(irq >= vrc5477_irq_base);
  61         db_assert(irq < vrc5477_irq_base+ NUM_5477_IRQ);
  62
  63         /* clear the interrupt bit */
  64         /* some irqs require the driver to clear the sources */
  65         ddb_out32(DDB_INTCLR32, 1 << (irq - vrc5477_irq_base));
  66
  67         /* disable interrupt - some handler will re-enable the irq
  68          * and if the interrupt is leveled, we will have infinite loop
  69          */
  70         ll_vrc5477_irq_disable(irq - vrc5477_irq_base);
  71 }
  72
  73 static void
  74 vrc5477_irq_end(unsigned int irq)
  75 {
  76         db_assert(vrc5477_irq_base != -1);
  77         db_assert(irq >= vrc5477_irq_base);
  78         db_assert(irq < vrc5477_irq_base + NUM_5477_IRQ);
  79
  80         if(!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
  81                 ll_vrc5477_irq_enable( irq - vrc5477_irq_base);
  82 }
  83
  84 struct irq_chip vrc5477_irq_controller = {
  85         .name = "vrc5477_irq",
  86         .ack = vrc5477_irq_ack,
  87         .mask = vrc5477_irq_disable,
  88         .mask_ack = vrc5477_irq_ack,
  89         .unmask = vrc5477_irq_enable,
  90         .end = vrc5477_irq_end
  91 };
  92
  93 void __init vrc5477_irq_init(u32 irq_base)
  94 {
  95         u32 i;
  96
  97         for (i= irq_base; i< irq_base+ NUM_5477_IRQ; i++)
  98                 set_irq_chip(i, &vrc5477_irq_controller);
  99
 100         vrc5477_irq_base = irq_base;
 101 }
 102
 103 void ll_vrc5477_irq_route(int vrc5477_irq, int ip)
 104 {
 105         u32 reg_value;
 106         u32 reg_bitmask;
 107         u32 reg_index;
 108
 109         db_assert(vrc5477_irq >= 0);
 110         db_assert(vrc5477_irq < NUM_5477_IRQ);
 111         db_assert(ip >= 0);
 112         db_assert((ip < 5) || (ip == 6));
 113
 114         reg_index = DDB_INTCTRL0 + vrc5477_irq/8*4;
 115         reg_value = ddb_in32(reg_index);
 116         reg_bitmask = 7 << (vrc5477_irq % 8 * 4);
 117         reg_value &= ~reg_bitmask;
 118         reg_value |= ip << (vrc5477_irq % 8 * 4);
 119         ddb_out32(reg_index, reg_value);
 120 }
 121
 122 void ll_vrc5477_irq_enable(int vrc5477_irq)
 123 {
 124         u32 reg_value;
 125         u32 reg_bitmask;
 126         u32 reg_index;
 127
 128         db_assert(vrc5477_irq >= 0);
 129         db_assert(vrc5477_irq < NUM_5477_IRQ);
 130
 131         reg_index = DDB_INTCTRL0 + vrc5477_irq/8*4;
 132         reg_value = ddb_in32(reg_index);
 133         reg_bitmask = 8 << (vrc5477_irq % 8 * 4);
 134         db_assert((reg_value & reg_bitmask) == 0);
 135         ddb_out32(reg_index, reg_value | reg_bitmask);
 136 }
 137
 138 void ll_vrc5477_irq_disable(int vrc5477_irq)
 139 {
 140         u32 reg_value;
 141         u32 reg_bitmask;
 142         u32 reg_index;
 143
 144         db_assert(vrc5477_irq >= 0);
 145         db_assert(vrc5477_irq < NUM_5477_IRQ);
 146
 147         reg_index = DDB_INTCTRL0 + vrc5477_irq/8*4;
 148         reg_value = ddb_in32(reg_index);
 149         reg_bitmask = 8 << (vrc5477_irq % 8 * 4);
 150
 151         /* we assert that the interrupt is enabled (perhaps over-zealous) */
 152         db_assert( (reg_value & reg_bitmask) != 0);
 153         ddb_out32(reg_index, reg_value & ~reg_bitmask);
 154 }