hw/intc/heathrow_pic.c

   1 /*
   2  * Heathrow PIC support (OldWorld PowerMac)
   3  *
   4  * Copyright (c) 2005-2007 Fabrice Bellard
   5  * Copyright (c) 2007 Jocelyn Mayer
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23  * THE SOFTWARE.
  24  */
  25
  26 #include "qemu/osdep.h"
  27 #include "migration/vmstate.h"
  28 #include "qemu/module.h"
  29 #include "hw/intc/heathrow_pic.h"
  30 #include "hw/irq.h"
  31 #include "trace.h"
  32
  33 static inline int heathrow_check_irq(HeathrowPICState *pic)
  34 {
  35     return (pic->events | (pic->levels & pic->level_triggered)) & pic->mask;
  36 }
  37
  38 /* update the CPU irq state */
  39 static void heathrow_update_irq(HeathrowState *s)
  40 {
  41     if (heathrow_check_irq(&s->pics[0]) ||
  42             heathrow_check_irq(&s->pics[1])) {
  43         qemu_irq_raise(s->irqs[0]);
  44     } else {
  45         qemu_irq_lower(s->irqs[0]);
  46     }
  47 }
  48
  49 static void heathrow_write(void *opaque, hwaddr addr,
  50                            uint64_t value, unsigned size)
  51 {
  52     HeathrowState *s = opaque;
  53     HeathrowPICState *pic;
  54     unsigned int n;
  55
  56     n = ((addr & 0xfff) - 0x10) >> 4;
  57     trace_heathrow_write(addr, n, value);
  58     if (n >= 2)
  59         return;
  60     pic = &s->pics[n];
  61     switch(addr & 0xf) {
  62     case 0x04:
  63         pic->mask = value;
  64         heathrow_update_irq(s);
  65         break;
  66     case 0x08:
  67         /* do not reset level triggered IRQs */
  68         value &= ~pic->level_triggered;
  69         pic->events &= ~value;
  70         heathrow_update_irq(s);
  71         break;
  72     default:
  73         break;
  74     }
  75 }
  76
  77 static uint64_t heathrow_read(void *opaque, hwaddr addr,
  78                               unsigned size)
  79 {
  80     HeathrowState *s = opaque;
  81     HeathrowPICState *pic;
  82     unsigned int n;
  83     uint32_t value;
  84
  85     n = ((addr & 0xfff) - 0x10) >> 4;
  86     if (n >= 2) {
  87         value = 0;
  88     } else {
  89         pic = &s->pics[n];
  90         switch(addr & 0xf) {
  91         case 0x0:
  92             value = pic->events;
  93             break;
  94         case 0x4:
  95             value = pic->mask;
  96             break;
  97         case 0xc:
  98             value = pic->levels;
  99             break;
 100         default:
 101             value = 0;
 102             break;
 103         }
 104     }
 105     trace_heathrow_read(addr, n, value);
 106     return value;
 107 }
 108
 109 static const MemoryRegionOps heathrow_ops = {
 110     .read = heathrow_read,
 111     .write = heathrow_write,
 112     .endianness = DEVICE_LITTLE_ENDIAN,
 113 };
 114
 115 static void heathrow_set_irq(void *opaque, int num, int level)
 116 {
 117     HeathrowState *s = opaque;
 118     HeathrowPICState *pic;
 119     unsigned int irq_bit;
 120     int last_level;
 121
 122     pic = &s->pics[1 - (num >> 5)];
 123     irq_bit = 1 << (num & 0x1f);
 124     last_level = (pic->levels & irq_bit) ? 1 : 0;
 125
 126     if (level) {
 127         pic->events |= irq_bit & ~pic->level_triggered;
 128         pic->levels |= irq_bit;
 129     } else {
 130         pic->levels &= ~irq_bit;
 131     }
 132
 133     if (last_level != level) {
 134         trace_heathrow_set_irq(num, level);
 135     }
 136
 137     heathrow_update_irq(s);
 138 }
 139
 140 static const VMStateDescription vmstate_heathrow_pic_one = {
 141     .name = "heathrow_pic_one",
 142     .version_id = 0,
 143     .minimum_version_id = 0,
 144     .fields = (const VMStateField[]) {
 145         VMSTATE_UINT32(events, HeathrowPICState),
 146         VMSTATE_UINT32(mask, HeathrowPICState),
 147         VMSTATE_UINT32(levels, HeathrowPICState),
 148         VMSTATE_UINT32(level_triggered, HeathrowPICState),
 149         VMSTATE_END_OF_LIST()
 150     }
 151 };
 152
 153 static const VMStateDescription vmstate_heathrow = {
 154     .name = "heathrow_pic",
 155     .version_id = 1,
 156     .minimum_version_id = 1,
 157     .fields = (const VMStateField[]) {
 158         VMSTATE_STRUCT_ARRAY(pics, HeathrowState, 2, 1,
 159                              vmstate_heathrow_pic_one, HeathrowPICState),
 160         VMSTATE_END_OF_LIST()
 161     }
 162 };
 163
 164 static void heathrow_reset(DeviceState *d)
 165 {
 166     HeathrowState *s = HEATHROW(d);
 167
 168     s->pics[0].level_triggered = 0;
 169     s->pics[1].level_triggered = 0x1ff00000;
 170 }
 171
 172 static void heathrow_init(Object *obj)
 173 {
 174     HeathrowState *s = HEATHROW(obj);
 175     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
 176
 177     /* only 1 CPU */
 178     qdev_init_gpio_out(DEVICE(obj), s->irqs, 1);
 179
 180     qdev_init_gpio_in(DEVICE(obj), heathrow_set_irq, HEATHROW_NUM_IRQS);
 181
 182     memory_region_init_io(&s->mem, OBJECT(s), &heathrow_ops, s,
 183                           "heathrow-pic", 0x1000);
 184     sysbus_init_mmio(sbd, &s->mem);
 185 }
 186
 187 static void heathrow_class_init(ObjectClass *oc, void *data)
 188 {
 189     DeviceClass *dc = DEVICE_CLASS(oc);
 190
 191     device_class_set_legacy_reset(dc, heathrow_reset);
 192     dc->vmsd = &vmstate_heathrow;
 193     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 194 }
 195
 196 static const TypeInfo heathrow_type_info = {
 197     .name = TYPE_HEATHROW,
 198     .parent = TYPE_SYS_BUS_DEVICE,
 199     .instance_size = sizeof(HeathrowState),
 200     .instance_init = heathrow_init,
 201     .class_init = heathrow_class_init,
 202 };
 203
 204 static void heathrow_register_types(void)
 205 {
 206     type_register_static(&heathrow_type_info);
 207 }
 208
 209 type_init(heathrow_register_types)