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 #include "hw/hw.h"
  26 #include "hw/ppc/mac.h"
  27
  28 /* debug PIC */
  29 //#define DEBUG_PIC
  30
  31 #ifdef DEBUG_PIC
  32 #define PIC_DPRINTF(fmt, ...)                                   \
  33     do { printf("PIC: " fmt , ## __VA_ARGS__); } while (0)
  34 #else
  35 #define PIC_DPRINTF(fmt, ...)
  36 #endif
  37
  38 typedef struct HeathrowPIC {
  39     uint32_t events;
  40     uint32_t mask;
  41     uint32_t levels;
  42     uint32_t level_triggered;
  43 } HeathrowPIC;
  44
  45 typedef struct HeathrowPICS {
  46     MemoryRegion mem;
  47     HeathrowPIC pics[2];
  48     qemu_irq *irqs;
  49 } HeathrowPICS;
  50
  51 static inline int check_irq(HeathrowPIC *pic)
  52 {
  53     return (pic->events | (pic->levels & pic->level_triggered)) & pic->mask;
  54 }
  55
  56 /* update the CPU irq state */
  57 static void heathrow_pic_update(HeathrowPICS *s)
  58 {
  59     if (check_irq(&s->pics[0]) || check_irq(&s->pics[1])) {
  60         qemu_irq_raise(s->irqs[0]);
  61     } else {
  62         qemu_irq_lower(s->irqs[0]);
  63     }
  64 }
  65
  66 static void pic_write(void *opaque, hwaddr addr,
  67                       uint64_t value, unsigned size)
  68 {
  69     HeathrowPICS *s = opaque;
  70     HeathrowPIC *pic;
  71     unsigned int n;
  72
  73     n = ((addr & 0xfff) - 0x10) >> 4;
  74     PIC_DPRINTF("writel: " TARGET_FMT_plx " %u: %08x\n", addr, n, value);
  75     if (n >= 2)
  76         return;
  77     pic = &s->pics[n];
  78     switch(addr & 0xf) {
  79     case 0x04:
  80         pic->mask = value;
  81         heathrow_pic_update(s);
  82         break;
  83     case 0x08:
  84         /* do not reset level triggered IRQs */
  85         value &= ~pic->level_triggered;
  86         pic->events &= ~value;
  87         heathrow_pic_update(s);
  88         break;
  89     default:
  90         break;
  91     }
  92 }
  93
  94 static uint64_t pic_read(void *opaque, hwaddr addr,
  95                          unsigned size)
  96 {
  97     HeathrowPICS *s = opaque;
  98     HeathrowPIC *pic;
  99     unsigned int n;
 100     uint32_t value;
 101
 102     n = ((addr & 0xfff) - 0x10) >> 4;
 103     if (n >= 2) {
 104         value = 0;
 105     } else {
 106         pic = &s->pics[n];
 107         switch(addr & 0xf) {
 108         case 0x0:
 109             value = pic->events;
 110             break;
 111         case 0x4:
 112             value = pic->mask;
 113             break;
 114         case 0xc:
 115             value = pic->levels;
 116             break;
 117         default:
 118             value = 0;
 119             break;
 120         }
 121     }
 122     PIC_DPRINTF("readl: " TARGET_FMT_plx " %u: %08x\n", addr, n, value);
 123     return value;
 124 }
 125
 126 static const MemoryRegionOps heathrow_pic_ops = {
 127     .read = pic_read,
 128     .write = pic_write,
 129     .endianness = DEVICE_LITTLE_ENDIAN,
 130 };
 131
 132 static void heathrow_pic_set_irq(void *opaque, int num, int level)
 133 {
 134     HeathrowPICS *s = opaque;
 135     HeathrowPIC *pic;
 136     unsigned int irq_bit;
 137
 138 #if defined(DEBUG)
 139     {
 140         static int last_level[64];
 141         if (last_level[num] != level) {
 142             PIC_DPRINTF("set_irq: num=0x%02x level=%d\n", num, level);
 143             last_level[num] = level;
 144         }
 145     }
 146 #endif
 147     pic = &s->pics[1 - (num >> 5)];
 148     irq_bit = 1 << (num & 0x1f);
 149     if (level) {
 150         pic->events |= irq_bit & ~pic->level_triggered;
 151         pic->levels |= irq_bit;
 152     } else {
 153         pic->levels &= ~irq_bit;
 154     }
 155     heathrow_pic_update(s);
 156 }
 157
 158 static const VMStateDescription vmstate_heathrow_pic_one = {
 159     .name = "heathrow_pic_one",
 160     .version_id = 0,
 161     .minimum_version_id = 0,
 162     .fields = (VMStateField[]) {
 163         VMSTATE_UINT32(events, HeathrowPIC),
 164         VMSTATE_UINT32(mask, HeathrowPIC),
 165         VMSTATE_UINT32(levels, HeathrowPIC),
 166         VMSTATE_UINT32(level_triggered, HeathrowPIC),
 167         VMSTATE_END_OF_LIST()
 168     }
 169 };
 170
 171 static const VMStateDescription vmstate_heathrow_pic = {
 172     .name = "heathrow_pic",
 173     .version_id = 1,
 174     .minimum_version_id = 1,
 175     .fields = (VMStateField[]) {
 176         VMSTATE_STRUCT_ARRAY(pics, HeathrowPICS, 2, 1,
 177                              vmstate_heathrow_pic_one, HeathrowPIC),
 178         VMSTATE_END_OF_LIST()
 179     }
 180 };
 181
 182 static void heathrow_pic_reset_one(HeathrowPIC *s)
 183 {
 184     memset(s, '\0', sizeof(HeathrowPIC));
 185 }
 186
 187 static void heathrow_pic_reset(void *opaque)
 188 {
 189     HeathrowPICS *s = opaque;
 190
 191     heathrow_pic_reset_one(&s->pics[0]);
 192     heathrow_pic_reset_one(&s->pics[1]);
 193
 194     s->pics[0].level_triggered = 0;
 195     s->pics[1].level_triggered = 0x1ff00000;
 196 }
 197
 198 qemu_irq *heathrow_pic_init(MemoryRegion **pmem,
 199                             int nb_cpus, qemu_irq **irqs)
 200 {
 201     HeathrowPICS *s;
 202
 203     s = g_malloc0(sizeof(HeathrowPICS));
 204     /* only 1 CPU */
 205     s->irqs = irqs[0];
 206     memory_region_init_io(&s->mem, NULL, &heathrow_pic_ops, s,
 207                           "heathrow-pic", 0x1000);
 208     *pmem = &s->mem;
 209
 210     vmstate_register(NULL, -1, &vmstate_heathrow_pic, s);
 211     qemu_register_reset(heathrow_pic_reset, s);
 212     return qemu_allocate_irqs(heathrow_pic_set_irq, s, 64);
 213 }