hw/intc/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 "hw/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 #define TYPE_PL190 "pl190"
  19 #define PL190(obj) OBJECT_CHECK(PL190State, (obj), TYPE_PL190)
  20
  21 typedef struct PL190State {
  22     SysBusDevice parent_obj;
  23
  24     MemoryRegion iomem;
  25     uint32_t level;
  26     uint32_t soft_level;
  27     uint32_t irq_enable;
  28     uint32_t fiq_select;
  29     uint8_t vect_control[16];
  30     uint32_t vect_addr[PL190_NUM_PRIO];
  31     /* Mask containing interrupts with higher priority than this one.  */
  32     uint32_t prio_mask[PL190_NUM_PRIO + 1];
  33     int protected;
  34     /* Current priority level.  */
  35     int priority;
  36     int prev_prio[PL190_NUM_PRIO];
  37     qemu_irq irq;
  38     qemu_irq fiq;
  39 } PL190State;
  40
  41 static const unsigned char pl190_id[] =
  42 { 0x90, 0x11, 0x04, 0x00, 0x0D, 0xf0, 0x05, 0xb1 };
  43
  44 static inline uint32_t pl190_irq_level(PL190State *s)
  45 {
  46     return (s->level | s->soft_level) & s->irq_enable & ~s->fiq_select;
  47 }
  48
  49 /* Update interrupts.  */
  50 static void pl190_update(PL190State *s)
  51 {
  52     uint32_t level = pl190_irq_level(s);
  53     int set;
  54
  55     set = (level & s->prio_mask[s->priority]) != 0;
  56     qemu_set_irq(s->irq, set);
  57     set = ((s->level | s->soft_level) & s->fiq_select) != 0;
  58     qemu_set_irq(s->fiq, set);
  59 }
  60
  61 static void pl190_set_irq(void *opaque, int irq, int level)
  62 {
  63     PL190State *s = (PL190State *)opaque;
  64
  65     if (level)
  66         s->level |= 1u << irq;
  67     else
  68         s->level &= ~(1u << irq);
  69     pl190_update(s);
  70 }
  71
  72 static void pl190_update_vectors(PL190State *s)
  73 {
  74     uint32_t mask;
  75     int i;
  76     int n;
  77
  78     mask = 0;
  79     for (i = 0; i < 16; i++)
  80       {
  81         s->prio_mask[i] = mask;
  82         if (s->vect_control[i] & 0x20)
  83           {
  84             n = s->vect_control[i] & 0x1f;
  85             mask |= 1 << n;
  86           }
  87       }
  88     s->prio_mask[16] = mask;
  89     pl190_update(s);
  90 }
  91
  92 static uint64_t pl190_read(void *opaque, hwaddr offset,
  93                            unsigned size)
  94 {
  95     PL190State *s = (PL190State *)opaque;
  96     int i;
  97
  98     if (offset >= 0xfe0 && offset < 0x1000) {
  99         return pl190_id[(offset - 0xfe0) >> 2];
 100     }
 101     if (offset >= 0x100 && offset < 0x140) {
 102         return s->vect_addr[(offset - 0x100) >> 2];
 103     }
 104     if (offset >= 0x200 && offset < 0x240) {
 105         return s->vect_control[(offset - 0x200) >> 2];
 106     }
 107     switch (offset >> 2) {
 108     case 0: /* IRQSTATUS */
 109         return pl190_irq_level(s);
 110     case 1: /* FIQSATUS */
 111         return (s->level | s->soft_level) & s->fiq_select;
 112     case 2: /* RAWINTR */
 113         return s->level | s->soft_level;
 114     case 3: /* INTSELECT */
 115         return s->fiq_select;
 116     case 4: /* INTENABLE */
 117         return s->irq_enable;
 118     case 6: /* SOFTINT */
 119         return s->soft_level;
 120     case 8: /* PROTECTION */
 121         return s->protected;
 122     case 12: /* VECTADDR */
 123         /* Read vector address at the start of an ISR.  Increases the
 124          * current priority level to that of the current interrupt.
 125          *
 126          * Since an enabled interrupt X at priority P causes prio_mask[Y]
 127          * to have bit X set for all Y > P, this loop will stop with
 128          * i == the priority of the highest priority set interrupt.
 129          */
 130         for (i = 0; i < s->priority; i++) {
 131             if ((s->level | s->soft_level) & s->prio_mask[i + 1]) {
 132                 break;
 133             }
 134         }
 135
 136         /* Reading this value with no pending interrupts is undefined.
 137            We return the default address.  */
 138         if (i == PL190_NUM_PRIO)
 139           return s->vect_addr[16];
 140         if (i < s->priority)
 141           {
 142             s->prev_prio[i] = s->priority;
 143             s->priority = i;
 144             pl190_update(s);
 145           }
 146         return s->vect_addr[s->priority];
 147     case 13: /* DEFVECTADDR */
 148         return s->vect_addr[16];
 149     default:
 150         qemu_log_mask(LOG_GUEST_ERROR,
 151                       "pl190_read: Bad offset %x\n", (int)offset);
 152         return 0;
 153     }
 154 }
 155
 156 static void pl190_write(void *opaque, hwaddr offset,
 157                         uint64_t val, unsigned size)
 158 {
 159     PL190State *s = (PL190State *)opaque;
 160
 161     if (offset >= 0x100 && offset < 0x140) {
 162         s->vect_addr[(offset - 0x100) >> 2] = val;
 163         pl190_update_vectors(s);
 164         return;
 165     }
 166     if (offset >= 0x200 && offset < 0x240) {
 167         s->vect_control[(offset - 0x200) >> 2] = val;
 168         pl190_update_vectors(s);
 169         return;
 170     }
 171     switch (offset >> 2) {
 172     case 0: /* SELECT */
 173         /* This is a readonly register, but linux tries to write to it
 174            anyway.  Ignore the write.  */
 175         break;
 176     case 3: /* INTSELECT */
 177         s->fiq_select = val;
 178         break;
 179     case 4: /* INTENABLE */
 180         s->irq_enable |= val;
 181         break;
 182     case 5: /* INTENCLEAR */
 183         s->irq_enable &= ~val;
 184         break;
 185     case 6: /* SOFTINT */
 186         s->soft_level |= val;
 187         break;
 188     case 7: /* SOFTINTCLEAR */
 189         s->soft_level &= ~val;
 190         break;
 191     case 8: /* PROTECTION */
 192         /* TODO: Protection (supervisor only access) is not implemented.  */
 193         s->protected = val & 1;
 194         break;
 195     case 12: /* VECTADDR */
 196         /* Restore the previous priority level.  The value written is
 197            ignored.  */
 198         if (s->priority < PL190_NUM_PRIO)
 199             s->priority = s->prev_prio[s->priority];
 200         break;
 201     case 13: /* DEFVECTADDR */
 202         s->vect_addr[16] = val;
 203         break;
 204     case 0xc0: /* ITCR */
 205         if (val) {
 206             qemu_log_mask(LOG_UNIMP, "pl190: Test mode not implemented\n");
 207         }
 208         break;
 209     default:
 210         qemu_log_mask(LOG_GUEST_ERROR,
 211                      "pl190_write: Bad offset %x\n", (int)offset);
 212         return;
 213     }
 214     pl190_update(s);
 215 }
 216
 217 static const MemoryRegionOps pl190_ops = {
 218     .read = pl190_read,
 219     .write = pl190_write,
 220     .endianness = DEVICE_NATIVE_ENDIAN,
 221 };
 222
 223 static void pl190_reset(DeviceState *d)
 224 {
 225     PL190State *s = PL190(d);
 226     int i;
 227
 228     for (i = 0; i < 16; i++) {
 229         s->vect_addr[i] = 0;
 230         s->vect_control[i] = 0;
 231     }
 232     s->vect_addr[16] = 0;
 233     s->prio_mask[17] = 0xffffffff;
 234     s->priority = PL190_NUM_PRIO;
 235     pl190_update_vectors(s);
 236 }
 237
 238 static int pl190_init(SysBusDevice *sbd)
 239 {
 240     DeviceState *dev = DEVICE(sbd);
 241     PL190State *s = PL190(dev);
 242
 243     memory_region_init_io(&s->iomem, OBJECT(s), &pl190_ops, s, "pl190", 0x1000);
 244     sysbus_init_mmio(sbd, &s->iomem);
 245     qdev_init_gpio_in(dev, pl190_set_irq, 32);
 246     sysbus_init_irq(sbd, &s->irq);
 247     sysbus_init_irq(sbd, &s->fiq);
 248     return 0;
 249 }
 250
 251 static const VMStateDescription vmstate_pl190 = {
 252     .name = "pl190",
 253     .version_id = 1,
 254     .minimum_version_id = 1,
 255     .fields = (VMStateField[]) {
 256         VMSTATE_UINT32(level, PL190State),
 257         VMSTATE_UINT32(soft_level, PL190State),
 258         VMSTATE_UINT32(irq_enable, PL190State),
 259         VMSTATE_UINT32(fiq_select, PL190State),
 260         VMSTATE_UINT8_ARRAY(vect_control, PL190State, 16),
 261         VMSTATE_UINT32_ARRAY(vect_addr, PL190State, PL190_NUM_PRIO),
 262         VMSTATE_UINT32_ARRAY(prio_mask, PL190State, PL190_NUM_PRIO+1),
 263         VMSTATE_INT32(protected, PL190State),
 264         VMSTATE_INT32(priority, PL190State),
 265         VMSTATE_INT32_ARRAY(prev_prio, PL190State, PL190_NUM_PRIO),
 266         VMSTATE_END_OF_LIST()
 267     }
 268 };
 269
 270 static void pl190_class_init(ObjectClass *klass, void *data)
 271 {
 272     DeviceClass *dc = DEVICE_CLASS(klass);
 273     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
 274
 275     k->init = pl190_init;
 276     dc->reset = pl190_reset;
 277     dc->vmsd = &vmstate_pl190;
 278 }
 279
 280 static const TypeInfo pl190_info = {
 281     .name          = TYPE_PL190,
 282     .parent        = TYPE_SYS_BUS_DEVICE,
 283     .instance_size = sizeof(PL190State),
 284     .class_init    = pl190_class_init,
 285 };
 286
 287 static void pl190_register_types(void)
 288 {
 289     type_register_static(&pl190_info);
 290 }
 291
 292 type_init(pl190_register_types)