hw/pl190.c

   1 /*
   2  * Arm PrimeCell PL190 Vector Interrupt Controller
   3  *
   4  * Copyright (c) 2006 CodeSourcery.
   5  * Written by Paul Brook
   6  *
   7  * This code is licensed under the GPL.
   8  */
   9
  10 #include "sysbus.h"
  11
  12 /* The number of virtual priority levels.  16 user vectors plus the
  13    unvectored IRQ.  Chained interrupts would require an additional level
  14    if implemented.  */
  15
  16 #define PL190_NUM_PRIO 17
  17
  18 typedef struct {
  19     SysBusDevice busdev;
  20     MemoryRegion iomem;
  21     uint32_t level;
  22     uint32_t soft_level;
  23     uint32_t irq_enable;
  24     uint32_t fiq_select;
  25     uint8_t vect_control[16];
  26     uint32_t vect_addr[PL190_NUM_PRIO];
  27     /* Mask containing interrupts with higher priority than this one.  */
  28     uint32_t prio_mask[PL190_NUM_PRIO + 1];
  29     int protected;
  30     /* Current priority level.  */
  31     int priority;
  32     int prev_prio[PL190_NUM_PRIO];
  33     qemu_irq irq;
  34     qemu_irq fiq;
  35 } pl190_state;
  36
  37 static const unsigned char pl190_id[] =
  38 { 0x90, 0x11, 0x04, 0x00, 0x0D, 0xf0, 0x05, 0xb1 };
  39
  40 static inline uint32_t pl190_irq_level(pl190_state *s)
  41 {
  42     return (s->level | s->soft_level) & s->irq_enable & ~s->fiq_select;
  43 }
  44
  45 /* Update interrupts.  */
  46 static void pl190_update(pl190_state *s)
  47 {
  48     uint32_t level = pl190_irq_level(s);
  49     int set;
  50
  51     set = (level & s->prio_mask[s->priority]) != 0;
  52     qemu_set_irq(s->irq, set);
  53     set = ((s->level | s->soft_level) & s->fiq_select) != 0;
  54     qemu_set_irq(s->fiq, set);
  55 }
  56
  57 static void pl190_set_irq(void *opaque, int irq, int level)
  58 {
  59     pl190_state *s = (pl190_state *)opaque;
  60
  61     if (level)
  62         s->level |= 1u << irq;
  63     else
  64         s->level &= ~(1u << irq);
  65     pl190_update(s);
  66 }
  67
  68 static void pl190_update_vectors(pl190_state *s)
  69 {
  70     uint32_t mask;
  71     int i;
  72     int n;
  73
  74     mask = 0;
  75     for (i = 0; i < 16; i++)
  76       {
  77         s->prio_mask[i] = mask;
  78         if (s->vect_control[i] & 0x20)
  79           {
  80             n = s->vect_control[i] & 0x1f;
  81             mask |= 1 << n;
  82           }
  83       }
  84     s->prio_mask[16] = mask;
  85     pl190_update(s);
  86 }
  87
  88 static uint64_t pl190_read(void *opaque, hwaddr offset,
  89                            unsigned size)
  90 {
  91     pl190_state *s = (pl190_state *)opaque;
  92     int i;
  93
  94     if (offset >= 0xfe0 && offset < 0x1000) {
  95         return pl190_id[(offset - 0xfe0) >> 2];
  96     }
  97     if (offset >= 0x100 && offset < 0x140) {
  98         return s->vect_addr[(offset - 0x100) >> 2];
  99     }
 100     if (offset >= 0x200 && offset < 0x240) {
 101         return s->vect_control[(offset - 0x200) >> 2];
 102     }
 103     switch (offset >> 2) {
 104     case 0: /* IRQSTATUS */
 105         return pl190_irq_level(s);
 106     case 1: /* FIQSATUS */
 107         return (s->level | s->soft_level) & s->fiq_select;
 108     case 2: /* RAWINTR */
 109         return s->level | s->soft_level;
 110     case 3: /* INTSELECT */
 111         return s->fiq_select;
 112     case 4: /* INTENABLE */
 113         return s->irq_enable;
 114     case 6: /* SOFTINT */
 115         return s->soft_level;
 116     case 8: /* PROTECTION */
 117         return s->protected;
 118     case 12: /* VECTADDR */
 119         /* Read vector address at the start of an ISR.  Increases the
 120          * current priority level to that of the current interrupt.
 121          *
 122          * Since an enabled interrupt X at priority P causes prio_mask[Y]
 123          * to have bit X set for all Y > P, this loop will stop with
 124          * i == the priority of the highest priority set interrupt.
 125          */
 126         for (i = 0; i < s->priority; i++) {
 127             if ((s->level | s->soft_level) & s->prio_mask[i + 1]) {
 128                 break;
 129             }
 130         }
 131
 132         /* Reading this value with no pending interrupts is undefined.
 133            We return the default address.  */
 134         if (i == PL190_NUM_PRIO)
 135           return s->vect_addr[16];
 136         if (i < s->priority)
 137           {
 138             s->prev_prio[i] = s->priority;
 139             s->priority = i;
 140             pl190_update(s);
 141           }
 142         return s->vect_addr[s->priority];
 143     case 13: /* DEFVECTADDR */
 144         return s->vect_addr[16];
 145     default:
 146         qemu_log_mask(LOG_GUEST_ERROR,
 147                       "pl190_read: Bad offset %x\n", (int)offset);
 148         return 0;
 149     }
 150 }
 151
 152 static void pl190_write(void *opaque, hwaddr offset,
 153                         uint64_t val, unsigned size)
 154 {
 155     pl190_state *s = (pl190_state *)opaque;
 156
 157     if (offset >= 0x100 && offset < 0x140) {
 158         s->vect_addr[(offset - 0x100) >> 2] = val;
 159         pl190_update_vectors(s);
 160         return;
 161     }
 162     if (offset >= 0x200 && offset < 0x240) {
 163         s->vect_control[(offset - 0x200) >> 2] = val;
 164         pl190_update_vectors(s);
 165         return;
 166     }
 167     switch (offset >> 2) {
 168     case 0: /* SELECT */
 169         /* This is a readonly register, but linux tries to write to it
 170            anyway.  Ignore the write.  */
 171         break;
 172     case 3: /* INTSELECT */
 173         s->fiq_select = val;
 174         break;
 175     case 4: /* INTENABLE */
 176         s->irq_enable |= val;
 177         break;
 178     case 5: /* INTENCLEAR */
 179         s->irq_enable &= ~val;
 180         break;
 181     case 6: /* SOFTINT */
 182         s->soft_level |= val;
 183         break;
 184     case 7: /* SOFTINTCLEAR */
 185         s->soft_level &= ~val;
 186         break;
 187     case 8: /* PROTECTION */
 188         /* TODO: Protection (supervisor only access) is not implemented.  */
 189         s->protected = val & 1;
 190         break;
 191     case 12: /* VECTADDR */
 192         /* Restore the previous priority level.  The value written is
 193            ignored.  */
 194         if (s->priority < PL190_NUM_PRIO)
 195             s->priority = s->prev_prio[s->priority];
 196         break;
 197     case 13: /* DEFVECTADDR */
 198         s->vect_addr[16] = val;
 199         break;
 200     case 0xc0: /* ITCR */
 201         if (val) {
 202             qemu_log_mask(LOG_UNIMP, "pl190: Test mode not implemented\n");
 203         }
 204         break;
 205     default:
 206         qemu_log_mask(LOG_GUEST_ERROR,
 207                      "pl190_write: Bad offset %x\n", (int)offset);
 208         return;
 209     }
 210     pl190_update(s);
 211 }
 212
 213 static const MemoryRegionOps pl190_ops = {
 214     .read = pl190_read,
 215     .write = pl190_write,
 216     .endianness = DEVICE_NATIVE_ENDIAN,
 217 };
 218
 219 static void pl190_reset(DeviceState *d)
 220 {
 221   pl190_state *s = DO_UPCAST(pl190_state, busdev.qdev, d);
 222   int i;
 223
 224   for (i = 0; i < 16; i++)
 225     {
 226       s->vect_addr[i] = 0;
 227       s->vect_control[i] = 0;
 228     }
 229   s->vect_addr[16] = 0;
 230   s->prio_mask[17] = 0xffffffff;
 231   s->priority = PL190_NUM_PRIO;
 232   pl190_update_vectors(s);
 233 }
 234
 235 static int pl190_init(SysBusDevice *dev)
 236 {
 237     pl190_state *s = FROM_SYSBUS(pl190_state, dev);
 238
 239     memory_region_init_io(&s->iomem, &pl190_ops, s, "pl190", 0x1000);
 240     sysbus_init_mmio(dev, &s->iomem);
 241     qdev_init_gpio_in(&dev->qdev, pl190_set_irq, 32);
 242     sysbus_init_irq(dev, &s->irq);
 243     sysbus_init_irq(dev, &s->fiq);
 244     return 0;
 245 }
 246
 247 static const VMStateDescription vmstate_pl190 = {
 248     .name = "pl190",
 249     .version_id = 1,
 250     .minimum_version_id = 1,
 251     .fields = (VMStateField[]) {
 252         VMSTATE_UINT32(level, pl190_state),
 253         VMSTATE_UINT32(soft_level, pl190_state),
 254         VMSTATE_UINT32(irq_enable, pl190_state),
 255         VMSTATE_UINT32(fiq_select, pl190_state),
 256         VMSTATE_UINT8_ARRAY(vect_control, pl190_state, 16),
 257         VMSTATE_UINT32_ARRAY(vect_addr, pl190_state, PL190_NUM_PRIO),
 258         VMSTATE_UINT32_ARRAY(prio_mask, pl190_state, PL190_NUM_PRIO+1),
 259         VMSTATE_INT32(protected, pl190_state),
 260         VMSTATE_INT32(priority, pl190_state),
 261         VMSTATE_INT32_ARRAY(prev_prio, pl190_state, PL190_NUM_PRIO),
 262         VMSTATE_END_OF_LIST()
 263     }
 264 };
 265
 266 static void pl190_class_init(ObjectClass *klass, void *data)
 267 {
 268     DeviceClass *dc = DEVICE_CLASS(klass);
 269     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
 270
 271     k->init = pl190_init;
 272     dc->no_user = 1;
 273     dc->reset = pl190_reset;
 274     dc->vmsd = &vmstate_pl190;
 275 }
 276
 277 static TypeInfo pl190_info = {
 278     .name          = "pl190",
 279     .parent        = TYPE_SYS_BUS_DEVICE,
 280     .instance_size = sizeof(pl190_state),
 281     .class_init    = pl190_class_init,
 282 };
 283
 284 static void pl190_register_types(void)
 285 {
 286     type_register_static(&pl190_info);
 287 }
 288
 289 type_init(pl190_register_types)