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-rw-r--r--hw/intc/arm_gic.c723
1 files changed, 723 insertions, 0 deletions
diff --git a/hw/intc/arm_gic.c b/hw/intc/arm_gic.c
new file mode 100644
index 0000000000..bcb072bbcf
--- /dev/null
+++ b/hw/intc/arm_gic.c
@@ -0,0 +1,723 @@
+/*
+ * ARM Generic/Distributed Interrupt Controller
+ *
+ * Copyright (c) 2006-2007 CodeSourcery.
+ * Written by Paul Brook
+ *
+ * This code is licensed under the GPL.
+ */
+
+/* This file contains implementation code for the RealView EB interrupt
+ * controller, MPCore distributed interrupt controller and ARMv7-M
+ * Nested Vectored Interrupt Controller.
+ * It is compiled in two ways:
+ *  (1) as a standalone file to produce a sysbus device which is a GIC
+ *  that can be used on the realview board and as one of the builtin
+ *  private peripherals for the ARM MP CPUs (11MPCore, A9, etc)
+ *  (2) by being directly #included into armv7m_nvic.c to produce the
+ *  armv7m_nvic device.
+ */
+
+#include "hw/sysbus.h"
+#include "hw/arm_gic_internal.h"
+
+//#define DEBUG_GIC
+
+#ifdef DEBUG_GIC
+#define DPRINTF(fmt, ...) \
+do { fprintf(stderr, "arm_gic: " fmt , ## __VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) do {} while(0)
+#endif
+
+static const uint8_t gic_id[] = {
+    0x90, 0x13, 0x04, 0x00, 0x0d, 0xf0, 0x05, 0xb1
+};
+
+#define NUM_CPU(s) ((s)->num_cpu)
+
+static inline int gic_get_current_cpu(GICState *s)
+{
+    if (s->num_cpu > 1) {
+        CPUState *cpu = ENV_GET_CPU(cpu_single_env);
+        return cpu->cpu_index;
+    }
+    return 0;
+}
+
+/* TODO: Many places that call this routine could be optimized.  */
+/* Update interrupt status after enabled or pending bits have been changed.  */
+void gic_update(GICState *s)
+{
+    int best_irq;
+    int best_prio;
+    int irq;
+    int level;
+    int cpu;
+    int cm;
+
+    for (cpu = 0; cpu < NUM_CPU(s); cpu++) {
+        cm = 1 << cpu;
+        s->current_pending[cpu] = 1023;
+        if (!s->enabled || !s->cpu_enabled[cpu]) {
+            qemu_irq_lower(s->parent_irq[cpu]);
+            return;
+        }
+        best_prio = 0x100;
+        best_irq = 1023;
+        for (irq = 0; irq < s->num_irq; irq++) {
+            if (GIC_TEST_ENABLED(irq, cm) && GIC_TEST_PENDING(irq, cm)) {
+                if (GIC_GET_PRIORITY(irq, cpu) < best_prio) {
+                    best_prio = GIC_GET_PRIORITY(irq, cpu);
+                    best_irq = irq;
+                }
+            }
+        }
+        level = 0;
+        if (best_prio < s->priority_mask[cpu]) {
+            s->current_pending[cpu] = best_irq;
+            if (best_prio < s->running_priority[cpu]) {
+                DPRINTF("Raised pending IRQ %d (cpu %d)\n", best_irq, cpu);
+                level = 1;
+            }
+        }
+        qemu_set_irq(s->parent_irq[cpu], level);
+    }
+}
+
+void gic_set_pending_private(GICState *s, int cpu, int irq)
+{
+    int cm = 1 << cpu;
+
+    if (GIC_TEST_PENDING(irq, cm))
+        return;
+
+    DPRINTF("Set %d pending cpu %d\n", irq, cpu);
+    GIC_SET_PENDING(irq, cm);
+    gic_update(s);
+}
+
+/* Process a change in an external IRQ input.  */
+static void gic_set_irq(void *opaque, int irq, int level)
+{
+    /* Meaning of the 'irq' parameter:
+     *  [0..N-1] : external interrupts
+     *  [N..N+31] : PPI (internal) interrupts for CPU 0
+     *  [N+32..N+63] : PPI (internal interrupts for CPU 1
+     *  ...
+     */
+    GICState *s = (GICState *)opaque;
+    int cm, target;
+    if (irq < (s->num_irq - GIC_INTERNAL)) {
+        /* The first external input line is internal interrupt 32.  */
+        cm = ALL_CPU_MASK;
+        irq += GIC_INTERNAL;
+        target = GIC_TARGET(irq);
+    } else {
+        int cpu;
+        irq -= (s->num_irq - GIC_INTERNAL);
+        cpu = irq / GIC_INTERNAL;
+        irq %= GIC_INTERNAL;
+        cm = 1 << cpu;
+        target = cm;
+    }
+
+    if (level == GIC_TEST_LEVEL(irq, cm)) {
+        return;
+    }
+
+    if (level) {
+        GIC_SET_LEVEL(irq, cm);
+        if (GIC_TEST_TRIGGER(irq) || GIC_TEST_ENABLED(irq, cm)) {
+            DPRINTF("Set %d pending mask %x\n", irq, target);
+            GIC_SET_PENDING(irq, target);
+        }
+    } else {
+        GIC_CLEAR_LEVEL(irq, cm);
+    }
+    gic_update(s);
+}
+
+static void gic_set_running_irq(GICState *s, int cpu, int irq)
+{
+    s->running_irq[cpu] = irq;
+    if (irq == 1023) {
+        s->running_priority[cpu] = 0x100;
+    } else {
+        s->running_priority[cpu] = GIC_GET_PRIORITY(irq, cpu);
+    }
+    gic_update(s);
+}
+
+uint32_t gic_acknowledge_irq(GICState *s, int cpu)
+{
+    int new_irq;
+    int cm = 1 << cpu;
+    new_irq = s->current_pending[cpu];
+    if (new_irq == 1023
+            || GIC_GET_PRIORITY(new_irq, cpu) >= s->running_priority[cpu]) {
+        DPRINTF("ACK no pending IRQ\n");
+        return 1023;
+    }
+    s->last_active[new_irq][cpu] = s->running_irq[cpu];
+    /* Clear pending flags for both level and edge triggered interrupts.
+       Level triggered IRQs will be reasserted once they become inactive.  */
+    GIC_CLEAR_PENDING(new_irq, GIC_TEST_MODEL(new_irq) ? ALL_CPU_MASK : cm);
+    gic_set_running_irq(s, cpu, new_irq);
+    DPRINTF("ACK %d\n", new_irq);
+    return new_irq;
+}
+
+void gic_complete_irq(GICState *s, int cpu, int irq)
+{
+    int update = 0;
+    int cm = 1 << cpu;
+    DPRINTF("EOI %d\n", irq);
+    if (irq >= s->num_irq) {
+        /* This handles two cases:
+         * 1. If software writes the ID of a spurious interrupt [ie 1023]
+         * to the GICC_EOIR, the GIC ignores that write.
+         * 2. If software writes the number of a non-existent interrupt
+         * this must be a subcase of "value written does not match the last
+         * valid interrupt value read from the Interrupt Acknowledge
+         * register" and so this is UNPREDICTABLE. We choose to ignore it.
+         */
+        return;
+    }
+    if (s->running_irq[cpu] == 1023)
+        return; /* No active IRQ.  */
+    /* Mark level triggered interrupts as pending if they are still
+       raised.  */
+    if (!GIC_TEST_TRIGGER(irq) && GIC_TEST_ENABLED(irq, cm)
+        && GIC_TEST_LEVEL(irq, cm) && (GIC_TARGET(irq) & cm) != 0) {
+        DPRINTF("Set %d pending mask %x\n", irq, cm);
+        GIC_SET_PENDING(irq, cm);
+        update = 1;
+    }
+    if (irq != s->running_irq[cpu]) {
+        /* Complete an IRQ that is not currently running.  */
+        int tmp = s->running_irq[cpu];
+        while (s->last_active[tmp][cpu] != 1023) {
+            if (s->last_active[tmp][cpu] == irq) {
+                s->last_active[tmp][cpu] = s->last_active[irq][cpu];
+                break;
+            }
+            tmp = s->last_active[tmp][cpu];
+        }
+        if (update) {
+            gic_update(s);
+        }
+    } else {
+        /* Complete the current running IRQ.  */
+        gic_set_running_irq(s, cpu, s->last_active[s->running_irq[cpu]][cpu]);
+    }
+}
+
+static uint32_t gic_dist_readb(void *opaque, hwaddr offset)
+{
+    GICState *s = (GICState *)opaque;
+    uint32_t res;
+    int irq;
+    int i;
+    int cpu;
+    int cm;
+    int mask;
+
+    cpu = gic_get_current_cpu(s);
+    cm = 1 << cpu;
+    if (offset < 0x100) {
+        if (offset == 0)
+            return s->enabled;
+        if (offset == 4)
+            return ((s->num_irq / 32) - 1) | ((NUM_CPU(s) - 1) << 5);
+        if (offset < 0x08)
+            return 0;
+        if (offset >= 0x80) {
+            /* Interrupt Security , RAZ/WI */
+            return 0;
+        }
+        goto bad_reg;
+    } else if (offset < 0x200) {
+        /* Interrupt Set/Clear Enable.  */
+        if (offset < 0x180)
+            irq = (offset - 0x100) * 8;
+        else
+            irq = (offset - 0x180) * 8;
+        irq += GIC_BASE_IRQ;
+        if (irq >= s->num_irq)
+            goto bad_reg;
+        res = 0;
+        for (i = 0; i < 8; i++) {
+            if (GIC_TEST_ENABLED(irq + i, cm)) {
+                res |= (1 << i);
+            }
+        }
+    } else if (offset < 0x300) {
+        /* Interrupt Set/Clear Pending.  */
+        if (offset < 0x280)
+            irq = (offset - 0x200) * 8;
+        else
+            irq = (offset - 0x280) * 8;
+        irq += GIC_BASE_IRQ;
+        if (irq >= s->num_irq)
+            goto bad_reg;
+        res = 0;
+        mask = (irq < GIC_INTERNAL) ?  cm : ALL_CPU_MASK;
+        for (i = 0; i < 8; i++) {
+            if (GIC_TEST_PENDING(irq + i, mask)) {
+                res |= (1 << i);
+            }
+        }
+    } else if (offset < 0x400) {
+        /* Interrupt Active.  */
+        irq = (offset - 0x300) * 8 + GIC_BASE_IRQ;
+        if (irq >= s->num_irq)
+            goto bad_reg;
+        res = 0;
+        mask = (irq < GIC_INTERNAL) ?  cm : ALL_CPU_MASK;
+        for (i = 0; i < 8; i++) {
+            if (GIC_TEST_ACTIVE(irq + i, mask)) {
+                res |= (1 << i);
+            }
+        }
+    } else if (offset < 0x800) {
+        /* Interrupt Priority.  */
+        irq = (offset - 0x400) + GIC_BASE_IRQ;
+        if (irq >= s->num_irq)
+            goto bad_reg;
+        res = GIC_GET_PRIORITY(irq, cpu);
+    } else if (offset < 0xc00) {
+        /* Interrupt CPU Target.  */
+        if (s->num_cpu == 1 && s->revision != REV_11MPCORE) {
+            /* For uniprocessor GICs these RAZ/WI */
+            res = 0;
+        } else {
+            irq = (offset - 0x800) + GIC_BASE_IRQ;
+            if (irq >= s->num_irq) {
+                goto bad_reg;
+            }
+            if (irq >= 29 && irq <= 31) {
+                res = cm;
+            } else {
+                res = GIC_TARGET(irq);
+            }
+        }
+    } else if (offset < 0xf00) {
+        /* Interrupt Configuration.  */
+        irq = (offset - 0xc00) * 2 + GIC_BASE_IRQ;
+        if (irq >= s->num_irq)
+            goto bad_reg;
+        res = 0;
+        for (i = 0; i < 4; i++) {
+            if (GIC_TEST_MODEL(irq + i))
+                res |= (1 << (i * 2));
+            if (GIC_TEST_TRIGGER(irq + i))
+                res |= (2 << (i * 2));
+        }
+    } else if (offset < 0xfe0) {
+        goto bad_reg;
+    } else /* offset >= 0xfe0 */ {
+        if (offset & 3) {
+            res = 0;
+        } else {
+            res = gic_id[(offset - 0xfe0) >> 2];
+        }
+    }
+    return res;
+bad_reg:
+    qemu_log_mask(LOG_GUEST_ERROR,
+                  "gic_dist_readb: Bad offset %x\n", (int)offset);
+    return 0;
+}
+
+static uint32_t gic_dist_readw(void *opaque, hwaddr offset)
+{
+    uint32_t val;
+    val = gic_dist_readb(opaque, offset);
+    val |= gic_dist_readb(opaque, offset + 1) << 8;
+    return val;
+}
+
+static uint32_t gic_dist_readl(void *opaque, hwaddr offset)
+{
+    uint32_t val;
+    val = gic_dist_readw(opaque, offset);
+    val |= gic_dist_readw(opaque, offset + 2) << 16;
+    return val;
+}
+
+static void gic_dist_writeb(void *opaque, hwaddr offset,
+                            uint32_t value)
+{
+    GICState *s = (GICState *)opaque;
+    int irq;
+    int i;
+    int cpu;
+
+    cpu = gic_get_current_cpu(s);
+    if (offset < 0x100) {
+        if (offset == 0) {
+            s->enabled = (value & 1);
+            DPRINTF("Distribution %sabled\n", s->enabled ? "En" : "Dis");
+        } else if (offset < 4) {
+            /* ignored.  */
+        } else if (offset >= 0x80) {
+            /* Interrupt Security Registers, RAZ/WI */
+        } else {
+            goto bad_reg;
+        }
+    } else if (offset < 0x180) {
+        /* Interrupt Set Enable.  */
+        irq = (offset - 0x100) * 8 + GIC_BASE_IRQ;
+        if (irq >= s->num_irq)
+            goto bad_reg;
+        if (irq < 16)
+          value = 0xff;
+        for (i = 0; i < 8; i++) {
+            if (value & (1 << i)) {
+                int mask =
+                    (irq < GIC_INTERNAL) ? (1 << cpu) : GIC_TARGET(irq + i);
+                int cm = (irq < GIC_INTERNAL) ? (1 << cpu) : ALL_CPU_MASK;
+
+                if (!GIC_TEST_ENABLED(irq + i, cm)) {
+                    DPRINTF("Enabled IRQ %d\n", irq + i);
+                }
+                GIC_SET_ENABLED(irq + i, cm);
+                /* If a raised level triggered IRQ enabled then mark
+                   is as pending.  */
+                if (GIC_TEST_LEVEL(irq + i, mask)
+                        && !GIC_TEST_TRIGGER(irq + i)) {
+                    DPRINTF("Set %d pending mask %x\n", irq + i, mask);
+                    GIC_SET_PENDING(irq + i, mask);
+                }
+            }
+        }
+    } else if (offset < 0x200) {
+        /* Interrupt Clear Enable.  */
+        irq = (offset - 0x180) * 8 + GIC_BASE_IRQ;
+        if (irq >= s->num_irq)
+            goto bad_reg;
+        if (irq < 16)
+          value = 0;
+        for (i = 0; i < 8; i++) {
+            if (value & (1 << i)) {
+                int cm = (irq < GIC_INTERNAL) ? (1 << cpu) : ALL_CPU_MASK;
+
+                if (GIC_TEST_ENABLED(irq + i, cm)) {
+                    DPRINTF("Disabled IRQ %d\n", irq + i);
+                }
+                GIC_CLEAR_ENABLED(irq + i, cm);
+            }
+        }
+    } else if (offset < 0x280) {
+        /* Interrupt Set Pending.  */
+        irq = (offset - 0x200) * 8 + GIC_BASE_IRQ;
+        if (irq >= s->num_irq)
+            goto bad_reg;
+        if (irq < 16)
+          irq = 0;
+
+        for (i = 0; i < 8; i++) {
+            if (value & (1 << i)) {
+                GIC_SET_PENDING(irq + i, GIC_TARGET(irq + i));
+            }
+        }
+    } else if (offset < 0x300) {
+        /* Interrupt Clear Pending.  */
+        irq = (offset - 0x280) * 8 + GIC_BASE_IRQ;
+        if (irq >= s->num_irq)
+            goto bad_reg;
+        for (i = 0; i < 8; i++) {
+            /* ??? This currently clears the pending bit for all CPUs, even
+               for per-CPU interrupts.  It's unclear whether this is the
+               corect behavior.  */
+            if (value & (1 << i)) {
+                GIC_CLEAR_PENDING(irq + i, ALL_CPU_MASK);
+            }
+        }
+    } else if (offset < 0x400) {
+        /* Interrupt Active.  */
+        goto bad_reg;
+    } else if (offset < 0x800) {
+        /* Interrupt Priority.  */
+        irq = (offset - 0x400) + GIC_BASE_IRQ;
+        if (irq >= s->num_irq)
+            goto bad_reg;
+        if (irq < GIC_INTERNAL) {
+            s->priority1[irq][cpu] = value;
+        } else {
+            s->priority2[irq - GIC_INTERNAL] = value;
+        }
+    } else if (offset < 0xc00) {
+        /* Interrupt CPU Target. RAZ/WI on uniprocessor GICs, with the
+         * annoying exception of the 11MPCore's GIC.
+         */
+        if (s->num_cpu != 1 || s->revision == REV_11MPCORE) {
+            irq = (offset - 0x800) + GIC_BASE_IRQ;
+            if (irq >= s->num_irq) {
+                goto bad_reg;
+            }
+            if (irq < 29) {
+                value = 0;
+            } else if (irq < GIC_INTERNAL) {
+                value = ALL_CPU_MASK;
+            }
+            s->irq_target[irq] = value & ALL_CPU_MASK;
+        }
+    } else if (offset < 0xf00) {
+        /* Interrupt Configuration.  */
+        irq = (offset - 0xc00) * 4 + GIC_BASE_IRQ;
+        if (irq >= s->num_irq)
+            goto bad_reg;
+        if (irq < GIC_INTERNAL)
+            value |= 0xaa;
+        for (i = 0; i < 4; i++) {
+            if (value & (1 << (i * 2))) {
+                GIC_SET_MODEL(irq + i);
+            } else {
+                GIC_CLEAR_MODEL(irq + i);
+            }
+            if (value & (2 << (i * 2))) {
+                GIC_SET_TRIGGER(irq + i);
+            } else {
+                GIC_CLEAR_TRIGGER(irq + i);
+            }
+        }
+    } else {
+        /* 0xf00 is only handled for 32-bit writes.  */
+        goto bad_reg;
+    }
+    gic_update(s);
+    return;
+bad_reg:
+    qemu_log_mask(LOG_GUEST_ERROR,
+                  "gic_dist_writeb: Bad offset %x\n", (int)offset);
+}
+
+static void gic_dist_writew(void *opaque, hwaddr offset,
+                            uint32_t value)
+{
+    gic_dist_writeb(opaque, offset, value & 0xff);
+    gic_dist_writeb(opaque, offset + 1, value >> 8);
+}
+
+static void gic_dist_writel(void *opaque, hwaddr offset,
+                            uint32_t value)
+{
+    GICState *s = (GICState *)opaque;
+    if (offset == 0xf00) {
+        int cpu;
+        int irq;
+        int mask;
+
+        cpu = gic_get_current_cpu(s);
+        irq = value & 0x3ff;
+        switch ((value >> 24) & 3) {
+        case 0:
+            mask = (value >> 16) & ALL_CPU_MASK;
+            break;
+        case 1:
+            mask = ALL_CPU_MASK ^ (1 << cpu);
+            break;
+        case 2:
+            mask = 1 << cpu;
+            break;
+        default:
+            DPRINTF("Bad Soft Int target filter\n");
+            mask = ALL_CPU_MASK;
+            break;
+        }
+        GIC_SET_PENDING(irq, mask);
+        gic_update(s);
+        return;
+    }
+    gic_dist_writew(opaque, offset, value & 0xffff);
+    gic_dist_writew(opaque, offset + 2, value >> 16);
+}
+
+static const MemoryRegionOps gic_dist_ops = {
+    .old_mmio = {
+        .read = { gic_dist_readb, gic_dist_readw, gic_dist_readl, },
+        .write = { gic_dist_writeb, gic_dist_writew, gic_dist_writel, },
+    },
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static uint32_t gic_cpu_read(GICState *s, int cpu, int offset)
+{
+    switch (offset) {
+    case 0x00: /* Control */
+        return s->cpu_enabled[cpu];
+    case 0x04: /* Priority mask */
+        return s->priority_mask[cpu];
+    case 0x08: /* Binary Point */
+        /* ??? Not implemented.  */
+        return 0;
+    case 0x0c: /* Acknowledge */
+        return gic_acknowledge_irq(s, cpu);
+    case 0x14: /* Running Priority */
+        return s->running_priority[cpu];
+    case 0x18: /* Highest Pending Interrupt */
+        return s->current_pending[cpu];
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "gic_cpu_read: Bad offset %x\n", (int)offset);
+        return 0;
+    }
+}
+
+static void gic_cpu_write(GICState *s, int cpu, int offset, uint32_t value)
+{
+    switch (offset) {
+    case 0x00: /* Control */
+        s->cpu_enabled[cpu] = (value & 1);
+        DPRINTF("CPU %d %sabled\n", cpu, s->cpu_enabled[cpu] ? "En" : "Dis");
+        break;
+    case 0x04: /* Priority mask */
+        s->priority_mask[cpu] = (value & 0xff);
+        break;
+    case 0x08: /* Binary Point */
+        /* ??? Not implemented.  */
+        break;
+    case 0x10: /* End Of Interrupt */
+        return gic_complete_irq(s, cpu, value & 0x3ff);
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "gic_cpu_write: Bad offset %x\n", (int)offset);
+        return;
+    }
+    gic_update(s);
+}
+
+/* Wrappers to read/write the GIC CPU interface for the current CPU */
+static uint64_t gic_thiscpu_read(void *opaque, hwaddr addr,
+                                 unsigned size)
+{
+    GICState *s = (GICState *)opaque;
+    return gic_cpu_read(s, gic_get_current_cpu(s), addr);
+}
+
+static void gic_thiscpu_write(void *opaque, hwaddr addr,
+                              uint64_t value, unsigned size)
+{
+    GICState *s = (GICState *)opaque;
+    gic_cpu_write(s, gic_get_current_cpu(s), addr, value);
+}
+
+/* Wrappers to read/write the GIC CPU interface for a specific CPU.
+ * These just decode the opaque pointer into GICState* + cpu id.
+ */
+static uint64_t gic_do_cpu_read(void *opaque, hwaddr addr,
+                                unsigned size)
+{
+    GICState **backref = (GICState **)opaque;
+    GICState *s = *backref;
+    int id = (backref - s->backref);
+    return gic_cpu_read(s, id, addr);
+}
+
+static void gic_do_cpu_write(void *opaque, hwaddr addr,
+                             uint64_t value, unsigned size)
+{
+    GICState **backref = (GICState **)opaque;
+    GICState *s = *backref;
+    int id = (backref - s->backref);
+    gic_cpu_write(s, id, addr, value);
+}
+
+static const MemoryRegionOps gic_thiscpu_ops = {
+    .read = gic_thiscpu_read,
+    .write = gic_thiscpu_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static const MemoryRegionOps gic_cpu_ops = {
+    .read = gic_do_cpu_read,
+    .write = gic_do_cpu_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+void gic_init_irqs_and_distributor(GICState *s, int num_irq)
+{
+    int i;
+
+    i = s->num_irq - GIC_INTERNAL;
+    /* For the GIC, also expose incoming GPIO lines for PPIs for each CPU.
+     * GPIO array layout is thus:
+     *  [0..N-1] SPIs
+     *  [N..N+31] PPIs for CPU 0
+     *  [N+32..N+63] PPIs for CPU 1
+     *   ...
+     */
+    if (s->revision != REV_NVIC) {
+        i += (GIC_INTERNAL * s->num_cpu);
+    }
+    qdev_init_gpio_in(&s->busdev.qdev, gic_set_irq, i);
+    for (i = 0; i < NUM_CPU(s); i++) {
+        sysbus_init_irq(&s->busdev, &s->parent_irq[i]);
+    }
+    memory_region_init_io(&s->iomem, &gic_dist_ops, s, "gic_dist", 0x1000);
+}
+
+static void arm_gic_realize(DeviceState *dev, Error **errp)
+{
+    /* Device instance realize function for the GIC sysbus device */
+    int i;
+    GICState *s = ARM_GIC(dev);
+    SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
+    ARMGICClass *agc = ARM_GIC_GET_CLASS(s);
+
+    agc->parent_realize(dev, errp);
+    if (error_is_set(errp)) {
+        return;
+    }
+
+    gic_init_irqs_and_distributor(s, s->num_irq);
+
+    /* Memory regions for the CPU interfaces (NVIC doesn't have these):
+     * a region for "CPU interface for this core", then a region for
+     * "CPU interface for core 0", "for core 1", ...
+     * NB that the memory region size of 0x100 applies for the 11MPCore
+     * and also cores following the GIC v1 spec (ie A9).
+     * GIC v2 defines a larger memory region (0x1000) so this will need
+     * to be extended when we implement A15.
+     */
+    memory_region_init_io(&s->cpuiomem[0], &gic_thiscpu_ops, s,
+                          "gic_cpu", 0x100);
+    for (i = 0; i < NUM_CPU(s); i++) {
+        s->backref[i] = s;
+        memory_region_init_io(&s->cpuiomem[i+1], &gic_cpu_ops, &s->backref[i],
+                              "gic_cpu", 0x100);
+    }
+    /* Distributor */
+    sysbus_init_mmio(sbd, &s->iomem);
+    /* cpu interfaces (one for "current cpu" plus one per cpu) */
+    for (i = 0; i <= NUM_CPU(s); i++) {
+        sysbus_init_mmio(sbd, &s->cpuiomem[i]);
+    }
+}
+
+static void arm_gic_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    ARMGICClass *agc = ARM_GIC_CLASS(klass);
+
+    dc->no_user = 1;
+    agc->parent_realize = dc->realize;
+    dc->realize = arm_gic_realize;
+}
+
+static const TypeInfo arm_gic_info = {
+    .name = TYPE_ARM_GIC,
+    .parent = TYPE_ARM_GIC_COMMON,
+    .instance_size = sizeof(GICState),
+    .class_init = arm_gic_class_init,
+    .class_size = sizeof(ARMGICClass),
+};
+
+static void arm_gic_register_types(void)
+{
+    type_register_static(&arm_gic_info);
+}
+
+type_init(arm_gic_register_types)