hw/imx_avic.c

   1 /*
   2  * i.MX31 Vectored Interrupt Controller
   3  *
   4  * Note this is NOT the PL192 provided by ARM, but
   5  * a custom implementation by Freescale.
   6  *
   7  * Copyright (c) 2008 OKL
   8  * Copyright (c) 2011 NICTA Pty Ltd
   9  * Originally written by Hans Jiang
  10  *
  11  * This code is licensed under the GPL version 2 or later.  See
  12  * the COPYING file in the top-level directory.
  13  *
  14  * TODO: implement vectors.
  15  */
  16
  17 #include "hw/hw.h"
  18 #include "hw/sysbus.h"
  19 #include "qemu/host-utils.h"
  20
  21 #define DEBUG_INT 1
  22 #undef DEBUG_INT /* comment out for debugging */
  23
  24 #ifdef DEBUG_INT
  25 #define DPRINTF(fmt, args...) \
  26 do { printf("imx_avic: " fmt , ##args); } while (0)
  27 #else
  28 #define DPRINTF(fmt, args...) do {} while (0)
  29 #endif
  30
  31 /*
  32  * Define to 1 for messages about attempts to
  33  * access unimplemented registers or similar.
  34  */
  35 #define DEBUG_IMPLEMENTATION 1
  36 #if DEBUG_IMPLEMENTATION
  37 #  define IPRINTF(fmt, args...) \
  38     do  { fprintf(stderr, "imx_avic: " fmt, ##args); } while (0)
  39 #else
  40 #  define IPRINTF(fmt, args...) do {} while (0)
  41 #endif
  42
  43 #define IMX_AVIC_NUM_IRQS 64
  44
  45 /* Interrupt Control Bits */
  46 #define ABFLAG (1<<25)
  47 #define ABFEN (1<<24)
  48 #define NIDIS (1<<22) /* Normal Interrupt disable */
  49 #define FIDIS (1<<21) /* Fast interrupt disable */
  50 #define NIAD  (1<<20) /* Normal Interrupt Arbiter Rise ARM level */
  51 #define FIAD  (1<<19) /* Fast Interrupt Arbiter Rise ARM level */
  52 #define NM    (1<<18) /* Normal interrupt mode */
  53
  54
  55 #define PRIO_PER_WORD (sizeof(uint32_t) * 8 / 4)
  56 #define PRIO_WORDS (IMX_AVIC_NUM_IRQS/PRIO_PER_WORD)
  57
  58 typedef struct {
  59     SysBusDevice busdev;
  60     MemoryRegion iomem;
  61     uint64_t pending;
  62     uint64_t enabled;
  63     uint64_t is_fiq;
  64     uint32_t intcntl;
  65     uint32_t intmask;
  66     qemu_irq irq;
  67     qemu_irq fiq;
  68     uint32_t prio[PRIO_WORDS]; /* Priorities are 4-bits each */
  69 } IMXAVICState;
  70
  71 static const VMStateDescription vmstate_imx_avic = {
  72     .name = "imx-avic",
  73     .version_id = 1,
  74     .minimum_version_id = 1,
  75     .minimum_version_id_old = 1,
  76     .fields = (VMStateField[]) {
  77         VMSTATE_UINT64(pending, IMXAVICState),
  78         VMSTATE_UINT64(enabled, IMXAVICState),
  79         VMSTATE_UINT64(is_fiq, IMXAVICState),
  80         VMSTATE_UINT32(intcntl, IMXAVICState),
  81         VMSTATE_UINT32(intmask, IMXAVICState),
  82         VMSTATE_UINT32_ARRAY(prio, IMXAVICState, PRIO_WORDS),
  83         VMSTATE_END_OF_LIST()
  84     },
  85 };
  86
  87
  88
  89 static inline int imx_avic_prio(IMXAVICState *s, int irq)
  90 {
  91     uint32_t word = irq / PRIO_PER_WORD;
  92     uint32_t part = 4 * (irq % PRIO_PER_WORD);
  93     return 0xf & (s->prio[word] >> part);
  94 }
  95
  96 static inline void imx_avic_set_prio(IMXAVICState *s, int irq, int prio)
  97 {
  98     uint32_t word = irq / PRIO_PER_WORD;
  99     uint32_t part = 4 * (irq % PRIO_PER_WORD);
 100     uint32_t mask = ~(0xf << part);
 101     s->prio[word] &= mask;
 102     s->prio[word] |= prio << part;
 103 }
 104
 105 /* Update interrupts.  */
 106 static void imx_avic_update(IMXAVICState *s)
 107 {
 108     int i;
 109     uint64_t new = s->pending & s->enabled;
 110     uint64_t flags;
 111
 112     flags = new & s->is_fiq;
 113     qemu_set_irq(s->fiq, !!flags);
 114
 115     flags = new & ~s->is_fiq;
 116     if (!flags || (s->intmask == 0x1f)) {
 117         qemu_set_irq(s->irq, !!flags);
 118         return;
 119     }
 120
 121     /*
 122      * Take interrupt if there's a pending interrupt with
 123      * priority higher than the value of intmask
 124      */
 125     for (i = 0; i < IMX_AVIC_NUM_IRQS; i++) {
 126         if (flags & (1UL << i)) {
 127             if (imx_avic_prio(s, i) > s->intmask) {
 128                 qemu_set_irq(s->irq, 1);
 129                 return;
 130             }
 131         }
 132     }
 133     qemu_set_irq(s->irq, 0);
 134 }
 135
 136 static void imx_avic_set_irq(void *opaque, int irq, int level)
 137 {
 138     IMXAVICState *s = (IMXAVICState *)opaque;
 139
 140     if (level) {
 141         DPRINTF("Raising IRQ %d, prio %d\n",
 142                 irq, imx_avic_prio(s, irq));
 143         s->pending |= (1ULL << irq);
 144     } else {
 145         DPRINTF("Clearing IRQ %d, prio %d\n",
 146                 irq, imx_avic_prio(s, irq));
 147         s->pending &= ~(1ULL << irq);
 148     }
 149
 150     imx_avic_update(s);
 151 }
 152
 153
 154 static uint64_t imx_avic_read(void *opaque,
 155                              hwaddr offset, unsigned size)
 156 {
 157     IMXAVICState *s = (IMXAVICState *)opaque;
 158
 159
 160     DPRINTF("read(offset = 0x%x)\n", offset >> 2);
 161     switch (offset >> 2) {
 162     case 0: /* INTCNTL */
 163         return s->intcntl;
 164
 165     case 1: /* Normal Interrupt Mask Register, NIMASK */
 166         return s->intmask;
 167
 168     case 2: /* Interrupt Enable Number Register, INTENNUM */
 169     case 3: /* Interrupt Disable Number Register, INTDISNUM */
 170         return 0;
 171
 172     case 4: /* Interrupt Enabled Number Register High */
 173         return s->enabled >> 32;
 174
 175     case 5: /* Interrupt Enabled Number Register Low */
 176         return s->enabled & 0xffffffffULL;
 177
 178     case 6: /* Interrupt Type Register High */
 179         return s->is_fiq >> 32;
 180
 181     case 7: /* Interrupt Type Register Low */
 182         return s->is_fiq & 0xffffffffULL;
 183
 184     case 8: /* Normal Interrupt Priority Register 7 */
 185     case 9: /* Normal Interrupt Priority Register 6 */
 186     case 10:/* Normal Interrupt Priority Register 5 */
 187     case 11:/* Normal Interrupt Priority Register 4 */
 188     case 12:/* Normal Interrupt Priority Register 3 */
 189     case 13:/* Normal Interrupt Priority Register 2 */
 190     case 14:/* Normal Interrupt Priority Register 1 */
 191     case 15:/* Normal Interrupt Priority Register 0 */
 192         return s->prio[15-(offset>>2)];
 193
 194     case 16: /* Normal interrupt vector and status register */
 195     {
 196         /*
 197          * This returns the highest priority
 198          * outstanding interrupt.  Where there is more than
 199          * one pending IRQ with the same priority,
 200          * take the highest numbered one.
 201          */
 202         uint64_t flags = s->pending & s->enabled & ~s->is_fiq;
 203         int i;
 204         int prio = -1;
 205         int irq = -1;
 206         for (i = 63; i >= 0; --i) {
 207             if (flags & (1ULL<<i)) {
 208                 int irq_prio = imx_avic_prio(s, i);
 209                 if (irq_prio > prio) {
 210                     irq = i;
 211                     prio = irq_prio;
 212                 }
 213             }
 214         }
 215         if (irq >= 0) {
 216             imx_avic_set_irq(s, irq, 0);
 217             return irq << 16 | prio;
 218         }
 219         return 0xffffffffULL;
 220     }
 221     case 17:/* Fast Interrupt vector and status register */
 222     {
 223         uint64_t flags = s->pending & s->enabled & s->is_fiq;
 224         int i = ctz64(flags);
 225         if (i < 64) {
 226             imx_avic_set_irq(opaque, i, 0);
 227             return i;
 228         }
 229         return 0xffffffffULL;
 230     }
 231     case 18:/* Interrupt source register high */
 232         return s->pending >> 32;
 233
 234     case 19:/* Interrupt source register low */
 235         return s->pending & 0xffffffffULL;
 236
 237     case 20:/* Interrupt Force Register high */
 238     case 21:/* Interrupt Force Register low */
 239         return 0;
 240
 241     case 22:/* Normal Interrupt Pending Register High */
 242         return (s->pending & s->enabled & ~s->is_fiq) >> 32;
 243
 244     case 23:/* Normal Interrupt Pending Register Low */
 245         return (s->pending & s->enabled & ~s->is_fiq) & 0xffffffffULL;
 246
 247     case 24: /* Fast Interrupt Pending Register High  */
 248         return (s->pending & s->enabled & s->is_fiq) >> 32;
 249
 250     case 25: /* Fast Interrupt Pending Register Low  */
 251         return (s->pending & s->enabled & s->is_fiq) & 0xffffffffULL;
 252
 253     case 0x40:            /* AVIC vector 0, use for WFI WAR */
 254         return 0x4;
 255
 256     default:
 257         IPRINTF("imx_avic_read: Bad offset 0x%x\n", (int)offset);
 258         return 0;
 259     }
 260 }
 261
 262 static void imx_avic_write(void *opaque, hwaddr offset,
 263                           uint64_t val, unsigned size)
 264 {
 265     IMXAVICState *s = (IMXAVICState *)opaque;
 266
 267     /* Vector Registers not yet supported */
 268     if (offset >= 0x100 && offset <= 0x2fc) {
 269         IPRINTF("imx_avic_write to vector register %d ignored\n",
 270                 (unsigned int)((offset - 0x100) >> 2));
 271         return;
 272     }
 273
 274     DPRINTF("imx_avic_write(0x%x) = %x\n",
 275             (unsigned int)offset>>2, (unsigned int)val);
 276     switch (offset >> 2) {
 277     case 0: /* Interrupt Control Register, INTCNTL */
 278         s->intcntl = val & (ABFEN | NIDIS | FIDIS | NIAD | FIAD | NM);
 279         if (s->intcntl & ABFEN) {
 280             s->intcntl &= ~(val & ABFLAG);
 281         }
 282         break;
 283
 284     case 1: /* Normal Interrupt Mask Register, NIMASK */
 285         s->intmask = val & 0x1f;
 286         break;
 287
 288     case 2: /* Interrupt Enable Number Register, INTENNUM */
 289         DPRINTF("enable(%d)\n", (int)val);
 290         val &= 0x3f;
 291         s->enabled |= (1ULL << val);
 292         break;
 293
 294     case 3: /* Interrupt Disable Number Register, INTDISNUM */
 295         DPRINTF("disable(%d)\n", (int)val);
 296         val &= 0x3f;
 297         s->enabled &= ~(1ULL << val);
 298         break;
 299
 300     case 4: /* Interrupt Enable Number Register High */
 301         s->enabled = (s->enabled & 0xffffffffULL) | (val << 32);
 302         break;
 303
 304     case 5: /* Interrupt Enable Number Register Low */
 305         s->enabled = (s->enabled & 0xffffffff00000000ULL) | val;
 306         break;
 307
 308     case 6: /* Interrupt Type Register High */
 309         s->is_fiq = (s->is_fiq & 0xffffffffULL) | (val << 32);
 310         break;
 311
 312     case 7: /* Interrupt Type Register Low */
 313         s->is_fiq = (s->is_fiq & 0xffffffff00000000ULL) | val;
 314         break;
 315
 316     case 8: /* Normal Interrupt Priority Register 7 */
 317     case 9: /* Normal Interrupt Priority Register 6 */
 318     case 10:/* Normal Interrupt Priority Register 5 */
 319     case 11:/* Normal Interrupt Priority Register 4 */
 320     case 12:/* Normal Interrupt Priority Register 3 */
 321     case 13:/* Normal Interrupt Priority Register 2 */
 322     case 14:/* Normal Interrupt Priority Register 1 */
 323     case 15:/* Normal Interrupt Priority Register 0 */
 324         s->prio[15-(offset>>2)] = val;
 325         break;
 326
 327         /* Read-only registers, writes ignored */
 328     case 16:/* Normal Interrupt Vector and Status register */
 329     case 17:/* Fast Interrupt vector and status register */
 330     case 18:/* Interrupt source register high */
 331     case 19:/* Interrupt source register low */
 332         return;
 333
 334     case 20:/* Interrupt Force Register high */
 335         s->pending = (s->pending & 0xffffffffULL) | (val << 32);
 336         break;
 337
 338     case 21:/* Interrupt Force Register low */
 339         s->pending = (s->pending & 0xffffffff00000000ULL) | val;
 340         break;
 341
 342     case 22:/* Normal Interrupt Pending Register High */
 343     case 23:/* Normal Interrupt Pending Register Low */
 344     case 24: /* Fast Interrupt Pending Register High  */
 345     case 25: /* Fast Interrupt Pending Register Low  */
 346         return;
 347
 348     default:
 349         IPRINTF("imx_avic_write: Bad offset %x\n", (int)offset);
 350     }
 351     imx_avic_update(s);
 352 }
 353
 354 static const MemoryRegionOps imx_avic_ops = {
 355     .read = imx_avic_read,
 356     .write = imx_avic_write,
 357     .endianness = DEVICE_NATIVE_ENDIAN,
 358 };
 359
 360 static void imx_avic_reset(DeviceState *dev)
 361 {
 362     IMXAVICState *s = container_of(dev, IMXAVICState, busdev.qdev);
 363     s->pending = 0;
 364     s->enabled = 0;
 365     s->is_fiq = 0;
 366     s->intmask = 0x1f;
 367     s->intcntl = 0;
 368     memset(s->prio, 0, sizeof s->prio);
 369 }
 370
 371 static int imx_avic_init(SysBusDevice *dev)
 372 {
 373     IMXAVICState *s = FROM_SYSBUS(IMXAVICState, dev);;
 374
 375     memory_region_init_io(&s->iomem, &imx_avic_ops, s, "imx_avic", 0x1000);
 376     sysbus_init_mmio(dev, &s->iomem);
 377
 378     qdev_init_gpio_in(&dev->qdev, imx_avic_set_irq, IMX_AVIC_NUM_IRQS);
 379     sysbus_init_irq(dev, &s->irq);
 380     sysbus_init_irq(dev, &s->fiq);
 381
 382     return 0;
 383 }
 384
 385
 386 static void imx_avic_class_init(ObjectClass *klass, void *data)
 387 {
 388     DeviceClass *dc = DEVICE_CLASS(klass);
 389     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
 390     k->init = imx_avic_init;
 391     dc->vmsd = &vmstate_imx_avic;
 392     dc->reset = imx_avic_reset;
 393     dc->desc = "i.MX Advanced Vector Interrupt Controller";
 394 }
 395
 396 static const TypeInfo imx_avic_info = {
 397     .name = "imx_avic",
 398     .parent = TYPE_SYS_BUS_DEVICE,
 399     .instance_size = sizeof(IMXAVICState),
 400     .class_init = imx_avic_class_init,
 401 };
 402
 403 static void imx_avic_register_types(void)
 404 {
 405     type_register_static(&imx_avic_info);
 406 }
 407
 408 type_init(imx_avic_register_types)