hw/arm_gic.c

   1 /*
   2  * ARM Generic/Distributed Interrupt Controller
   3  *
   4  * Copyright (c) 2006-2007 CodeSourcery.
   5  * Written by Paul Brook
   6  *
   7  * This code is licenced under the GPL.
   8  */
   9
  10 /* This file contains implementation code for the RealView EB interrupt
  11    controller, MPCore distributed interrupt controller and ARMv7-M
  12    Nested Vectored Interrupt Controller.  */
  13
  14 //#define DEBUG_GIC
  15
  16 #ifdef DEBUG_GIC
  17 #define DPRINTF(fmt, args...) \
  18 do { printf("arm_gic: " fmt , ##args); } while (0)
  19 #else
  20 #define DPRINTF(fmt, args...) do {} while(0)
  21 #endif
  22
  23 #ifdef NVIC
  24 static const uint8_t gic_id[] =
  25 { 0x00, 0xb0, 0x1b, 0x00, 0x0d, 0xe0, 0x05, 0xb1 };
  26 #define GIC_DIST_OFFSET 0
  27 /* The NVIC has 16 internal vectors.  However these are not exposed
  28    through the normal GIC interface.  */
  29 #define GIC_BASE_IRQ    32
  30 #else
  31 static const uint8_t gic_id[] =
  32 { 0x90, 0x13, 0x04, 0x00, 0x0d, 0xf0, 0x05, 0xb1 };
  33 #define GIC_DIST_OFFSET 0x1000
  34 #define GIC_BASE_IRQ    0
  35 #endif
  36
  37 typedef struct gic_irq_state
  38 {
  39     /* ??? The documentation seems to imply the enable bits are global, even
  40        for per-cpu interrupts.  This seems strange.  */
  41     unsigned enabled:1;
  42     unsigned pending:NCPU;
  43     unsigned active:NCPU;
  44     unsigned level:1;
  45     unsigned model:1; /* 0 = N:N, 1 = 1:N */
  46     unsigned trigger:1; /* nonzero = edge triggered.  */
  47 } gic_irq_state;
  48
  49 #define ALL_CPU_MASK ((1 << NCPU) - 1)
  50
  51 #define GIC_SET_ENABLED(irq) s->irq_state[irq].enabled = 1
  52 #define GIC_CLEAR_ENABLED(irq) s->irq_state[irq].enabled = 0
  53 #define GIC_TEST_ENABLED(irq) s->irq_state[irq].enabled
  54 #define GIC_SET_PENDING(irq, cm) s->irq_state[irq].pending |= (cm)
  55 #define GIC_CLEAR_PENDING(irq, cm) s->irq_state[irq].pending &= ~(cm)
  56 #define GIC_TEST_PENDING(irq, cm) ((s->irq_state[irq].pending & (cm)) != 0)
  57 #define GIC_SET_ACTIVE(irq, cm) s->irq_state[irq].active |= (cm)
  58 #define GIC_CLEAR_ACTIVE(irq, cm) s->irq_state[irq].active &= ~(cm)
  59 #define GIC_TEST_ACTIVE(irq, cm) ((s->irq_state[irq].active & (cm)) != 0)
  60 #define GIC_SET_MODEL(irq) s->irq_state[irq].model = 1
  61 #define GIC_CLEAR_MODEL(irq) s->irq_state[irq].model = 0
  62 #define GIC_TEST_MODEL(irq) s->irq_state[irq].model
  63 #define GIC_SET_LEVEL(irq, cm) s->irq_state[irq].level = (cm)
  64 #define GIC_CLEAR_LEVEL(irq, cm) s->irq_state[irq].level &= ~(cm)
  65 #define GIC_TEST_LEVEL(irq, cm) ((s->irq_state[irq].level & (cm)) != 0)
  66 #define GIC_SET_TRIGGER(irq) s->irq_state[irq].trigger = 1
  67 #define GIC_CLEAR_TRIGGER(irq) s->irq_state[irq].trigger = 0
  68 #define GIC_TEST_TRIGGER(irq) s->irq_state[irq].trigger
  69 #define GIC_GET_PRIORITY(irq, cpu) \
  70   (((irq) < 32) ? s->priority1[irq][cpu] : s->priority2[(irq) - 32])
  71 #ifdef NVIC
  72 #define GIC_TARGET(irq) 1
  73 #else
  74 #define GIC_TARGET(irq) s->irq_target[irq]
  75 #endif
  76
  77 typedef struct gic_state
  78 {
  79     uint32_t base;
  80     qemu_irq parent_irq[NCPU];
  81     int enabled;
  82     int cpu_enabled[NCPU];
  83
  84     gic_irq_state irq_state[GIC_NIRQ];
  85 #ifndef NVIC
  86     int irq_target[GIC_NIRQ];
  87 #endif
  88     int priority1[32][NCPU];
  89     int priority2[GIC_NIRQ - 32];
  90     int last_active[GIC_NIRQ][NCPU];
  91
  92     int priority_mask[NCPU];
  93     int running_irq[NCPU];
  94     int running_priority[NCPU];
  95     int current_pending[NCPU];
  96
  97     qemu_irq *in;
  98 #ifdef NVIC
  99     void *nvic;
 100 #endif
 101 } gic_state;
 102
 103 /* TODO: Many places that call this routine could be optimized.  */
 104 /* Update interrupt status after enabled or pending bits have been changed.  */
 105 static void gic_update(gic_state *s)
 106 {
 107     int best_irq;
 108     int best_prio;
 109     int irq;
 110     int level;
 111     int cpu;
 112     int cm;
 113
 114     for (cpu = 0; cpu < NCPU; cpu++) {
 115         cm = 1 << cpu;
 116         s->current_pending[cpu] = 1023;
 117         if (!s->enabled || !s->cpu_enabled[cpu]) {
 118             qemu_irq_lower(s->parent_irq[cpu]);
 119             return;
 120         }
 121         best_prio = 0x100;
 122         best_irq = 1023;
 123         for (irq = 0; irq < GIC_NIRQ; irq++) {
 124             if (GIC_TEST_ENABLED(irq) && GIC_TEST_PENDING(irq, cm)) {
 125                 if (GIC_GET_PRIORITY(irq, cpu) < best_prio) {
 126                     best_prio = GIC_GET_PRIORITY(irq, cpu);
 127                     best_irq = irq;
 128                 }
 129             }
 130         }
 131         level = 0;
 132         if (best_prio <= s->priority_mask[cpu]) {
 133             s->current_pending[cpu] = best_irq;
 134             if (best_prio < s->running_priority[cpu]) {
 135                 DPRINTF("Raised pending IRQ %d\n", best_irq);
 136                 level = 1;
 137             }
 138         }
 139         qemu_set_irq(s->parent_irq[cpu], level);
 140     }
 141 }
 142
 143 static void __attribute__((unused))
 144 gic_set_pending_private(gic_state *s, int cpu, int irq)
 145 {
 146     int cm = 1 << cpu;
 147
 148     if (GIC_TEST_PENDING(irq, cm))
 149         return;
 150
 151     DPRINTF("Set %d pending cpu %d\n", irq, cpu);
 152     GIC_SET_PENDING(irq, cm);
 153     gic_update(s);
 154 }
 155
 156 /* Process a change in an external IRQ input.  */
 157 static void gic_set_irq(void *opaque, int irq, int level)
 158 {
 159     gic_state *s = (gic_state *)opaque;
 160     /* The first external input line is internal interrupt 32.  */
 161     irq += 32;
 162     if (level == GIC_TEST_LEVEL(irq, ALL_CPU_MASK))
 163         return;
 164
 165     if (level) {
 166         GIC_SET_LEVEL(irq, ALL_CPU_MASK);
 167         if (GIC_TEST_TRIGGER(irq) || GIC_TEST_ENABLED(irq)) {
 168             DPRINTF("Set %d pending mask %x\n", irq, GIC_TARGET(irq));
 169             GIC_SET_PENDING(irq, GIC_TARGET(irq));
 170         }
 171     } else {
 172         GIC_CLEAR_LEVEL(irq, ALL_CPU_MASK);
 173     }
 174     gic_update(s);
 175 }
 176
 177 static void gic_set_running_irq(gic_state *s, int cpu, int irq)
 178 {
 179     s->running_irq[cpu] = irq;
 180     if (irq == 1023) {
 181         s->running_priority[cpu] = 0x100;
 182     } else {
 183         s->running_priority[cpu] = GIC_GET_PRIORITY(irq, cpu);
 184     }
 185     gic_update(s);
 186 }
 187
 188 static uint32_t gic_acknowledge_irq(gic_state *s, int cpu)
 189 {
 190     int new_irq;
 191     int cm = 1 << cpu;
 192     new_irq = s->current_pending[cpu];
 193     if (new_irq == 1023
 194             || GIC_GET_PRIORITY(new_irq, cpu) >= s->running_priority[cpu]) {
 195         DPRINTF("ACK no pending IRQ\n");
 196         return 1023;
 197     }
 198     s->last_active[new_irq][cpu] = s->running_irq[cpu];
 199     /* Clear pending flags for both level and edge triggered interrupts.
 200        Level triggered IRQs will be reasserted once they become inactive.  */
 201     GIC_CLEAR_PENDING(new_irq, GIC_TEST_MODEL(new_irq) ? ALL_CPU_MASK : cm);
 202     gic_set_running_irq(s, cpu, new_irq);
 203     DPRINTF("ACK %d\n", new_irq);
 204     return new_irq;
 205 }
 206
 207 static void gic_complete_irq(gic_state * s, int cpu, int irq)
 208 {
 209     int update = 0;
 210     int cm = 1 << cpu;
 211     DPRINTF("EOI %d\n", irq);
 212     if (s->running_irq[cpu] == 1023)
 213         return; /* No active IRQ.  */
 214     if (irq != 1023) {
 215         /* Mark level triggered interrupts as pending if they are still
 216            raised.  */
 217         if (!GIC_TEST_TRIGGER(irq) && GIC_TEST_ENABLED(irq)
 218                 && GIC_TEST_LEVEL(irq, cm) && (GIC_TARGET(irq) & cm) != 0) {
 219             DPRINTF("Set %d pending mask %x\n", irq, cm);
 220             GIC_SET_PENDING(irq, cm);
 221             update = 1;
 222         }
 223     }
 224     if (irq != s->running_irq[cpu]) {
 225         /* Complete an IRQ that is not currently running.  */
 226         int tmp = s->running_irq[cpu];
 227         while (s->last_active[tmp][cpu] != 1023) {
 228             if (s->last_active[tmp][cpu] == irq) {
 229                 s->last_active[tmp][cpu] = s->last_active[irq][cpu];
 230                 break;
 231             }
 232             tmp = s->last_active[tmp][cpu];
 233         }
 234         if (update) {
 235             gic_update(s);
 236         }
 237     } else {
 238         /* Complete the current running IRQ.  */
 239         gic_set_running_irq(s, cpu, s->last_active[s->running_irq[cpu]][cpu]);
 240     }
 241 }
 242
 243 static uint32_t gic_dist_readb(void *opaque, target_phys_addr_t offset)
 244 {
 245     gic_state *s = (gic_state *)opaque;
 246     uint32_t res;
 247     int irq;
 248     int i;
 249     int cpu;
 250     int cm;
 251     int mask;
 252
 253     cpu = gic_get_current_cpu();
 254     cm = 1 << cpu;
 255     offset -= s->base + GIC_DIST_OFFSET;
 256     if (offset < 0x100) {
 257 #ifndef NVIC
 258         if (offset == 0)
 259             return s->enabled;
 260         if (offset == 4)
 261             return ((GIC_NIRQ / 32) - 1) | ((NCPU - 1) << 5);
 262         if (offset < 0x08)
 263             return 0;
 264 #endif
 265         goto bad_reg;
 266     } else if (offset < 0x200) {
 267         /* Interrupt Set/Clear Enable.  */
 268         if (offset < 0x180)
 269             irq = (offset - 0x100) * 8;
 270         else
 271             irq = (offset - 0x180) * 8;
 272         irq += GIC_BASE_IRQ;
 273         if (irq >= GIC_NIRQ)
 274             goto bad_reg;
 275         res = 0;
 276         for (i = 0; i < 8; i++) {
 277             if (GIC_TEST_ENABLED(irq + i)) {
 278                 res |= (1 << i);
 279             }
 280         }
 281     } else if (offset < 0x300) {
 282         /* Interrupt Set/Clear Pending.  */
 283         if (offset < 0x280)
 284             irq = (offset - 0x200) * 8;
 285         else
 286             irq = (offset - 0x280) * 8;
 287         irq += GIC_BASE_IRQ;
 288         if (irq >= GIC_NIRQ)
 289             goto bad_reg;
 290         res = 0;
 291         mask = (irq < 32) ?  cm : ALL_CPU_MASK;
 292         for (i = 0; i < 8; i++) {
 293             if (GIC_TEST_PENDING(irq + i, mask)) {
 294                 res |= (1 << i);
 295             }
 296         }
 297     } else if (offset < 0x400) {
 298         /* Interrupt Active.  */
 299         irq = (offset - 0x300) * 8 + GIC_BASE_IRQ;
 300         if (irq >= GIC_NIRQ)
 301             goto bad_reg;
 302         res = 0;
 303         mask = (irq < 32) ?  cm : ALL_CPU_MASK;
 304         for (i = 0; i < 8; i++) {
 305             if (GIC_TEST_ACTIVE(irq + i, mask)) {
 306                 res |= (1 << i);
 307             }
 308         }
 309     } else if (offset < 0x800) {
 310         /* Interrupt Priority.  */
 311         irq = (offset - 0x400) + GIC_BASE_IRQ;
 312         if (irq >= GIC_NIRQ)
 313             goto bad_reg;
 314         res = GIC_GET_PRIORITY(irq, cpu);
 315 #ifndef NVIC
 316     } else if (offset < 0xc00) {
 317         /* Interrupt CPU Target.  */
 318         irq = (offset - 0x800) + GIC_BASE_IRQ;
 319         if (irq >= GIC_NIRQ)
 320             goto bad_reg;
 321         if (irq >= 29 && irq <= 31) {
 322             res = cm;
 323         } else {
 324             res = GIC_TARGET(irq);
 325         }
 326     } else if (offset < 0xf00) {
 327         /* Interrupt Configuration.  */
 328         irq = (offset - 0xc00) * 2 + GIC_BASE_IRQ;
 329         if (irq >= GIC_NIRQ)
 330             goto bad_reg;
 331         res = 0;
 332         for (i = 0; i < 4; i++) {
 333             if (GIC_TEST_MODEL(irq + i))
 334                 res |= (1 << (i * 2));
 335             if (GIC_TEST_TRIGGER(irq + i))
 336                 res |= (2 << (i * 2));
 337         }
 338 #endif
 339     } else if (offset < 0xfe0) {
 340         goto bad_reg;
 341     } else /* offset >= 0xfe0 */ {
 342         if (offset & 3) {
 343             res = 0;
 344         } else {
 345             res = gic_id[(offset - 0xfe0) >> 2];
 346         }
 347     }
 348     return res;
 349 bad_reg:
 350     cpu_abort(cpu_single_env, "gic_dist_readb: Bad offset %x\n", (int)offset);
 351     return 0;
 352 }
 353
 354 static uint32_t gic_dist_readw(void *opaque, target_phys_addr_t offset)
 355 {
 356     uint32_t val;
 357     val = gic_dist_readb(opaque, offset);
 358     val |= gic_dist_readb(opaque, offset + 1) << 8;
 359     return val;
 360 }
 361
 362 static uint32_t gic_dist_readl(void *opaque, target_phys_addr_t offset)
 363 {
 364     uint32_t val;
 365 #ifdef NVIC
 366     gic_state *s = (gic_state *)opaque;
 367     uint32_t addr;
 368     addr = offset - s->base;
 369     if (addr < 0x100 || addr > 0xd00)
 370         return nvic_readl(s->nvic, addr);
 371 #endif
 372     val = gic_dist_readw(opaque, offset);
 373     val |= gic_dist_readw(opaque, offset + 2) << 16;
 374     return val;
 375 }
 376
 377 static void gic_dist_writeb(void *opaque, target_phys_addr_t offset,
 378                             uint32_t value)
 379 {
 380     gic_state *s = (gic_state *)opaque;
 381     int irq;
 382     int i;
 383     int cpu;
 384
 385     cpu = gic_get_current_cpu();
 386     offset -= s->base + GIC_DIST_OFFSET;
 387     if (offset < 0x100) {
 388 #ifdef NVIC
 389         goto bad_reg;
 390 #else
 391         if (offset == 0) {
 392             s->enabled = (value & 1);
 393             DPRINTF("Distribution %sabled\n", s->enabled ? "En" : "Dis");
 394         } else if (offset < 4) {
 395             /* ignored.  */
 396         } else {
 397             goto bad_reg;
 398         }
 399 #endif
 400     } else if (offset < 0x180) {
 401         /* Interrupt Set Enable.  */
 402         irq = (offset - 0x100) * 8 + GIC_BASE_IRQ;
 403         if (irq >= GIC_NIRQ)
 404             goto bad_reg;
 405         if (irq < 16)
 406           value = 0xff;
 407         for (i = 0; i < 8; i++) {
 408             if (value & (1 << i)) {
 409                 int mask = (irq < 32) ? (1 << cpu) : GIC_TARGET(irq);
 410                 if (!GIC_TEST_ENABLED(irq + i))
 411                     DPRINTF("Enabled IRQ %d\n", irq + i);
 412                 GIC_SET_ENABLED(irq + i);
 413                 /* If a raised level triggered IRQ enabled then mark
 414                    is as pending.  */
 415                 if (GIC_TEST_LEVEL(irq + i, mask)
 416                         && !GIC_TEST_TRIGGER(irq + i)) {
 417                     DPRINTF("Set %d pending mask %x\n", irq + i, mask);
 418                     GIC_SET_PENDING(irq + i, mask);
 419                 }
 420             }
 421         }
 422     } else if (offset < 0x200) {
 423         /* Interrupt Clear Enable.  */
 424         irq = (offset - 0x180) * 8 + GIC_BASE_IRQ;
 425         if (irq >= GIC_NIRQ)
 426             goto bad_reg;
 427         if (irq < 16)
 428           value = 0;
 429         for (i = 0; i < 8; i++) {
 430             if (value & (1 << i)) {
 431                 if (GIC_TEST_ENABLED(irq + i))
 432                     DPRINTF("Disabled IRQ %d\n", irq + i);
 433                 GIC_CLEAR_ENABLED(irq + i);
 434             }
 435         }
 436     } else if (offset < 0x280) {
 437         /* Interrupt Set Pending.  */
 438         irq = (offset - 0x200) * 8 + GIC_BASE_IRQ;
 439         if (irq >= GIC_NIRQ)
 440             goto bad_reg;
 441         if (irq < 16)
 442           irq = 0;
 443
 444         for (i = 0; i < 8; i++) {
 445             if (value & (1 << i)) {
 446                 GIC_SET_PENDING(irq + i, GIC_TARGET(irq));
 447             }
 448         }
 449     } else if (offset < 0x300) {
 450         /* Interrupt Clear Pending.  */
 451         irq = (offset - 0x280) * 8 + GIC_BASE_IRQ;
 452         if (irq >= GIC_NIRQ)
 453             goto bad_reg;
 454         for (i = 0; i < 8; i++) {
 455             /* ??? This currently clears the pending bit for all CPUs, even
 456                for per-CPU interrupts.  It's unclear whether this is the
 457                corect behavior.  */
 458             if (value & (1 << i)) {
 459                 GIC_CLEAR_PENDING(irq + i, ALL_CPU_MASK);
 460             }
 461         }
 462     } else if (offset < 0x400) {
 463         /* Interrupt Active.  */
 464         goto bad_reg;
 465     } else if (offset < 0x800) {
 466         /* Interrupt Priority.  */
 467         irq = (offset - 0x400) + GIC_BASE_IRQ;
 468         if (irq >= GIC_NIRQ)
 469             goto bad_reg;
 470         if (irq < 32) {
 471             s->priority1[irq][cpu] = value;
 472         } else {
 473             s->priority2[irq - 32] = value;
 474         }
 475 #ifndef NVIC
 476     } else if (offset < 0xc00) {
 477         /* Interrupt CPU Target.  */
 478         irq = (offset - 0x800) + GIC_BASE_IRQ;
 479         if (irq >= GIC_NIRQ)
 480             goto bad_reg;
 481         if (irq < 29)
 482             value = 0;
 483         else if (irq < 32)
 484             value = ALL_CPU_MASK;
 485         s->irq_target[irq] = value & ALL_CPU_MASK;
 486     } else if (offset < 0xf00) {
 487         /* Interrupt Configuration.  */
 488         irq = (offset - 0xc00) * 4 + GIC_BASE_IRQ;
 489         if (irq >= GIC_NIRQ)
 490             goto bad_reg;
 491         if (irq < 32)
 492             value |= 0xaa;
 493         for (i = 0; i < 4; i++) {
 494             if (value & (1 << (i * 2))) {
 495                 GIC_SET_MODEL(irq + i);
 496             } else {
 497                 GIC_CLEAR_MODEL(irq + i);
 498             }
 499             if (value & (2 << (i * 2))) {
 500                 GIC_SET_TRIGGER(irq + i);
 501             } else {
 502                 GIC_CLEAR_TRIGGER(irq + i);
 503             }
 504         }
 505 #endif
 506     } else {
 507         /* 0xf00 is only handled for 32-bit writes.  */
 508         goto bad_reg;
 509     }
 510     gic_update(s);
 511     return;
 512 bad_reg:
 513     cpu_abort(cpu_single_env, "gic_dist_writeb: Bad offset %x\n", (int)offset);
 514 }
 515
 516 static void gic_dist_writew(void *opaque, target_phys_addr_t offset,
 517                             uint32_t value)
 518 {
 519     gic_dist_writeb(opaque, offset, value & 0xff);
 520     gic_dist_writeb(opaque, offset + 1, value >> 8);
 521 }
 522
 523 static void gic_dist_writel(void *opaque, target_phys_addr_t offset,
 524                             uint32_t value)
 525 {
 526     gic_state *s = (gic_state *)opaque;
 527 #ifdef NVIC
 528     uint32_t addr;
 529     addr = offset - s->base;
 530     if (addr < 0x100 || (addr > 0xd00 && addr != 0xf00)) {
 531         nvic_writel(s->nvic, addr, value);
 532         return;
 533     }
 534 #endif
 535     if (offset - s->base == GIC_DIST_OFFSET + 0xf00) {
 536         int cpu;
 537         int irq;
 538         int mask;
 539
 540         cpu = gic_get_current_cpu();
 541         irq = value & 0x3ff;
 542         switch ((value >> 24) & 3) {
 543         case 0:
 544             mask = (value >> 16) & ALL_CPU_MASK;
 545             break;
 546         case 1:
 547             mask = 1 << cpu;
 548             break;
 549         case 2:
 550             mask = ALL_CPU_MASK ^ (1 << cpu);
 551             break;
 552         default:
 553             DPRINTF("Bad Soft Int target filter\n");
 554             mask = ALL_CPU_MASK;
 555             break;
 556         }
 557         GIC_SET_PENDING(irq, mask);
 558         gic_update(s);
 559         return;
 560     }
 561     gic_dist_writew(opaque, offset, value & 0xffff);
 562     gic_dist_writew(opaque, offset + 2, value >> 16);
 563 }
 564
 565 static CPUReadMemoryFunc *gic_dist_readfn[] = {
 566    gic_dist_readb,
 567    gic_dist_readw,
 568    gic_dist_readl
 569 };
 570
 571 static CPUWriteMemoryFunc *gic_dist_writefn[] = {
 572    gic_dist_writeb,
 573    gic_dist_writew,
 574    gic_dist_writel
 575 };
 576
 577 #ifndef NVIC
 578 static uint32_t gic_cpu_read(gic_state *s, int cpu, int offset)
 579 {
 580     switch (offset) {
 581     case 0x00: /* Control */
 582         return s->cpu_enabled[cpu];
 583     case 0x04: /* Priority mask */
 584         return s->priority_mask[cpu];
 585     case 0x08: /* Binary Point */
 586         /* ??? Not implemented.  */
 587         return 0;
 588     case 0x0c: /* Acknowledge */
 589         return gic_acknowledge_irq(s, cpu);
 590     case 0x14: /* Runing Priority */
 591         return s->running_priority[cpu];
 592     case 0x18: /* Highest Pending Interrupt */
 593         return s->current_pending[cpu];
 594     default:
 595         cpu_abort(cpu_single_env, "gic_cpu_read: Bad offset %x\n",
 596                   (int)offset);
 597         return 0;
 598     }
 599 }
 600
 601 static void gic_cpu_write(gic_state *s, int cpu, int offset, uint32_t value)
 602 {
 603     switch (offset) {
 604     case 0x00: /* Control */
 605         s->cpu_enabled[cpu] = (value & 1);
 606         DPRINTF("CPU %sabled\n", s->cpu_enabled ? "En" : "Dis");
 607         break;
 608     case 0x04: /* Priority mask */
 609         s->priority_mask[cpu] = (value & 0xff);
 610         break;
 611     case 0x08: /* Binary Point */
 612         /* ??? Not implemented.  */
 613         break;
 614     case 0x10: /* End Of Interrupt */
 615         return gic_complete_irq(s, cpu, value & 0x3ff);
 616     default:
 617         cpu_abort(cpu_single_env, "gic_cpu_write: Bad offset %x\n",
 618                   (int)offset);
 619         return;
 620     }
 621     gic_update(s);
 622 }
 623 #endif
 624
 625 static void gic_reset(gic_state *s)
 626 {
 627     int i;
 628     memset(s->irq_state, 0, GIC_NIRQ * sizeof(gic_irq_state));
 629     for (i = 0 ; i < NCPU; i++) {
 630         s->priority_mask[i] = 0xf0;
 631         s->current_pending[i] = 1023;
 632         s->running_irq[i] = 1023;
 633         s->running_priority[i] = 0x100;
 634 #ifdef NVIC
 635         /* The NVIC doesn't have per-cpu interfaces, so enable by default.  */
 636         s->cpu_enabled[i] = 1;
 637 #else
 638         s->cpu_enabled[i] = 0;
 639 #endif
 640     }
 641     for (i = 0; i < 16; i++) {
 642         GIC_SET_ENABLED(i);
 643         GIC_SET_TRIGGER(i);
 644     }
 645 #ifdef NVIC
 646     /* The NVIC is always enabled.  */
 647     s->enabled = 1;
 648 #else
 649     s->enabled = 0;
 650 #endif
 651 }
 652
 653 static gic_state *gic_init(uint32_t base, qemu_irq *parent_irq)
 654 {
 655     gic_state *s;
 656     int iomemtype;
 657     int i;
 658
 659     s = (gic_state *)qemu_mallocz(sizeof(gic_state));
 660     if (!s)
 661         return NULL;
 662     s->in = qemu_allocate_irqs(gic_set_irq, s, GIC_NIRQ);
 663     for (i = 0; i < NCPU; i++) {
 664         s->parent_irq[i] = parent_irq[i];
 665     }
 666     iomemtype = cpu_register_io_memory(0, gic_dist_readfn,
 667                                        gic_dist_writefn, s);
 668     cpu_register_physical_memory(base + GIC_DIST_OFFSET, 0x00001000,
 669                                  iomemtype);
 670     s->base = base;
 671     gic_reset(s);
 672     return s;
 673 }