hw/puv3_intc.c

   1 /*
   2  * INTC device simulation in PKUnity SoC
   3  *
   4  * Copyright (C) 2010-2012 Guan Xuetao
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation, or any later version.
   9  * See the COPYING file in the top-level directory.
  10  */
  11 #include "sysbus.h"
  12
  13 #undef DEBUG_PUV3
  14 #include "puv3.h"
  15
  16 typedef struct {
  17     SysBusDevice busdev;
  18     MemoryRegion iomem;
  19     qemu_irq parent_irq;
  20
  21     uint32_t reg_ICMR;
  22     uint32_t reg_ICPR;
  23 } PUV3INTCState;
  24
  25 /* Update interrupt status after enabled or pending bits have been changed.  */
  26 static void puv3_intc_update(PUV3INTCState *s)
  27 {
  28     if (s->reg_ICMR & s->reg_ICPR) {
  29         qemu_irq_raise(s->parent_irq);
  30     } else {
  31         qemu_irq_lower(s->parent_irq);
  32     }
  33 }
  34
  35 /* Process a change in an external INTC input. */
  36 static void puv3_intc_handler(void *opaque, int irq, int level)
  37 {
  38     PUV3INTCState *s = opaque;
  39
  40     DPRINTF("irq 0x%x, level 0x%x\n", irq, level);
  41     if (level) {
  42         s->reg_ICPR |= (1 << irq);
  43     } else {
  44         s->reg_ICPR &= ~(1 << irq);
  45     }
  46     puv3_intc_update(s);
  47 }
  48
  49 static uint64_t puv3_intc_read(void *opaque, hwaddr offset,
  50         unsigned size)
  51 {
  52     PUV3INTCState *s = opaque;
  53     uint32_t ret = 0;
  54
  55     switch (offset) {
  56     case 0x04: /* INTC_ICMR */
  57         ret = s->reg_ICMR;
  58         break;
  59     case 0x0c: /* INTC_ICIP */
  60         ret = s->reg_ICPR; /* the same value with ICPR */
  61         break;
  62     default:
  63         DPRINTF("Bad offset %x\n", (int)offset);
  64     }
  65     DPRINTF("offset 0x%x, value 0x%x\n", offset, ret);
  66     return ret;
  67 }
  68
  69 static void puv3_intc_write(void *opaque, hwaddr offset,
  70         uint64_t value, unsigned size)
  71 {
  72     PUV3INTCState *s = opaque;
  73
  74     DPRINTF("offset 0x%x, value 0x%x\n", offset, value);
  75     switch (offset) {
  76     case 0x00: /* INTC_ICLR */
  77     case 0x14: /* INTC_ICCR */
  78         break;
  79     case 0x04: /* INTC_ICMR */
  80         s->reg_ICMR = value;
  81         break;
  82     default:
  83         DPRINTF("Bad offset 0x%x\n", (int)offset);
  84         return;
  85     }
  86     puv3_intc_update(s);
  87 }
  88
  89 static const MemoryRegionOps puv3_intc_ops = {
  90     .read = puv3_intc_read,
  91     .write = puv3_intc_write,
  92     .impl = {
  93         .min_access_size = 4,
  94         .max_access_size = 4,
  95     },
  96     .endianness = DEVICE_NATIVE_ENDIAN,
  97 };
  98
  99 static int puv3_intc_init(SysBusDevice *dev)
 100 {
 101     PUV3INTCState *s = FROM_SYSBUS(PUV3INTCState, dev);
 102
 103     qdev_init_gpio_in(&s->busdev.qdev, puv3_intc_handler, PUV3_IRQS_NR);
 104     sysbus_init_irq(&s->busdev, &s->parent_irq);
 105
 106     s->reg_ICMR = 0;
 107     s->reg_ICPR = 0;
 108
 109     memory_region_init_io(&s->iomem, &puv3_intc_ops, s, "puv3_intc",
 110             PUV3_REGS_OFFSET);
 111     sysbus_init_mmio(dev, &s->iomem);
 112
 113     return 0;
 114 }
 115
 116 static void puv3_intc_class_init(ObjectClass *klass, void *data)
 117 {
 118     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
 119
 120     sdc->init = puv3_intc_init;
 121 }
 122
 123 static const TypeInfo puv3_intc_info = {
 124     .name = "puv3_intc",
 125     .parent = TYPE_SYS_BUS_DEVICE,
 126     .instance_size = sizeof(PUV3INTCState),
 127     .class_init = puv3_intc_class_init,
 128 };
 129
 130 static void puv3_intc_register_type(void)
 131 {
 132     type_register_static(&puv3_intc_info);
 133 }
 134
 135 type_init(puv3_intc_register_type)