hw/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.h"
  26 #include "ppc_mac.h"
  27
  28 //#define DEBUG
  29
  30 typedef struct HeathrowPIC {
  31     uint32_t events;
  32     uint32_t mask;
  33     uint32_t levels;
  34     uint32_t level_triggered;
  35 } HeathrowPIC;
  36
  37 typedef struct HeathrowPICS {
  38     HeathrowPIC pics[2];
  39     qemu_irq *irqs;
  40 } HeathrowPICS;
  41
  42 static inline int check_irq(HeathrowPIC *pic)
  43 {
  44     return (pic->events | (pic->levels & pic->level_triggered)) & pic->mask;
  45 }
  46
  47 /* update the CPU irq state */
  48 static void heathrow_pic_update(HeathrowPICS *s)
  49 {
  50     if (check_irq(&s->pics[0]) || check_irq(&s->pics[1])) {
  51         qemu_irq_raise(s->irqs[0]);
  52     } else {
  53         qemu_irq_lower(s->irqs[0]);
  54     }
  55 }
  56
  57 static void pic_writel (void *opaque, target_phys_addr_t addr, uint32_t value)
  58 {
  59     HeathrowPICS *s = opaque;
  60     HeathrowPIC *pic;
  61     unsigned int n;
  62
  63 #ifdef TARGET_WORDS_BIGENDIAN
  64     value = bswap32(value);
  65 #endif
  66     n = ((addr & 0xfff) - 0x10) >> 4;
  67 #ifdef DEBUG
  68     printf("pic_writel: " PADDRX " %u: %08x\n", addr, n, value);
  69 #endif
  70     if (n >= 2)
  71         return;
  72     pic = &s->pics[n];
  73     switch(addr & 0xf) {
  74     case 0x04:
  75         pic->mask = value;
  76         heathrow_pic_update(s);
  77         break;
  78     case 0x08:
  79         /* do not reset level triggered IRQs */
  80         value &= ~pic->level_triggered;
  81         pic->events &= ~value;
  82         heathrow_pic_update(s);
  83         break;
  84     default:
  85         break;
  86     }
  87 }
  88
  89 static uint32_t pic_readl (void *opaque, target_phys_addr_t addr)
  90 {
  91     HeathrowPICS *s = opaque;
  92     HeathrowPIC *pic;
  93     unsigned int n;
  94     uint32_t value;
  95
  96     n = ((addr & 0xfff) - 0x10) >> 4;
  97     if (n >= 2) {
  98         value = 0;
  99     } else {
 100         pic = &s->pics[n];
 101         switch(addr & 0xf) {
 102         case 0x0:
 103             value = pic->events;
 104             break;
 105         case 0x4:
 106             value = pic->mask;
 107             break;
 108         case 0xc:
 109             value = pic->levels;
 110             break;
 111         default:
 112             value = 0;
 113             break;
 114         }
 115     }
 116 #ifdef DEBUG
 117     printf("pic_readl: " PADDRX " %u: %08x\n", addr, n, value);
 118 #endif
 119 #ifdef TARGET_WORDS_BIGENDIAN
 120     value = bswap32(value);
 121 #endif
 122     return value;
 123 }
 124
 125 static CPUWriteMemoryFunc *pic_write[] = {
 126     &pic_writel,
 127     &pic_writel,
 128     &pic_writel,
 129 };
 130
 131 static CPUReadMemoryFunc *pic_read[] = {
 132     &pic_readl,
 133     &pic_readl,
 134     &pic_readl,
 135 };
 136
 137
 138 static void heathrow_pic_set_irq(void *opaque, int num, int level)
 139 {
 140     HeathrowPICS *s = opaque;
 141     HeathrowPIC *pic;
 142     unsigned int irq_bit;
 143
 144 #if defined(DEBUG)
 145     {
 146         static int last_level[64];
 147         if (last_level[num] != level) {
 148             printf("set_irq: num=0x%02x level=%d\n", num, level);
 149             last_level[num] = level;
 150         }
 151     }
 152 #endif
 153     pic = &s->pics[1 - (num >> 5)];
 154     irq_bit = 1 << (num & 0x1f);
 155     if (level) {
 156         pic->events |= irq_bit & ~pic->level_triggered;
 157         pic->levels |= irq_bit;
 158     } else {
 159         pic->levels &= ~irq_bit;
 160     }
 161     heathrow_pic_update(s);
 162 }
 163
 164 qemu_irq *heathrow_pic_init(int *pmem_index,
 165                             int nb_cpus, qemu_irq **irqs)
 166 {
 167     HeathrowPICS *s;
 168
 169     s = qemu_mallocz(sizeof(HeathrowPICS));
 170     s->pics[0].level_triggered = 0;
 171     s->pics[1].level_triggered = 0x1ff00000;
 172     /* only 1 CPU */
 173     s->irqs = irqs[0];
 174     *pmem_index = cpu_register_io_memory(0, pic_read, pic_write, s);
 175
 176     return qemu_allocate_irqs(heathrow_pic_set_irq, s, 64);
 177 }