diff --git a/include/hw/cpu/cortex_mpcore.h b/include/hw/cpu/cortex_mpcore.h
index 1d94c8769d..0e7cca9e93 100644
--- a/include/hw/cpu/cortex_mpcore.h
+++ b/include/hw/cpu/cortex_mpcore.h
@@ -26,6 +26,10 @@
  * The A9 MPCore additionally contains:
  *  a System Control Unit
  *  some timers and watchdogs
+ *
+ * QEMU interface:
+ *  + QOM property "num-cores" which set the number of cores present in
+ *    the cluster.
  */
 #define TYPE_CORTEX_MPCORE_PRIV "cortex_mpcore_priv"
 OBJECT_DECLARE_TYPE(CortexMPPrivState, CortexMPPrivClass, CORTEX_MPCORE_PRIV)
@@ -46,6 +50,9 @@ struct CortexMPPrivState {
     SysBusDevice parent_obj;
 
     MemoryRegion container;
+
+    /* Properties */
+    uint32_t num_cores;
 };
 
 #define TYPE_A9MPCORE_PRIV "a9mpcore_priv"
@@ -54,7 +61,6 @@ OBJECT_DECLARE_SIMPLE_TYPE(A9MPPrivState, A9MPCORE_PRIV)
 struct A9MPPrivState {
     CortexMPPrivState parent_obj;
 
-    uint32_t num_cpu;
     uint32_t num_irq;
 
     A9SCUState scu;
@@ -70,7 +76,6 @@ OBJECT_DECLARE_SIMPLE_TYPE(A15MPPrivState, A15MPCORE_PRIV)
 struct A15MPPrivState {
     CortexMPPrivState parent_obj;
 
-    uint32_t num_cpu;
     uint32_t num_irq;
 
     GICState gic;
diff --git a/hw/arm/aspeed_ast2600.c b/hw/arm/aspeed_ast2600.c
index b965fbab5e..ca788e1cf0 100644
--- a/hw/arm/aspeed_ast2600.c
+++ b/hw/arm/aspeed_ast2600.c
@@ -330,7 +330,7 @@ static void aspeed_soc_ast2600_realize(DeviceState *dev, Error **errp)
     }
 
     /* A7MPCORE */
-    object_property_set_int(OBJECT(&a->a7mpcore), "num-cpu", sc->num_cpus,
+    object_property_set_int(OBJECT(&a->a7mpcore), "num-cores", sc->num_cpus,
                             &error_abort);
     object_property_set_int(OBJECT(&a->a7mpcore), "num-irq",
                             ROUND_UP(AST2600_MAX_IRQ + GIC_INTERNAL, 32),
diff --git a/hw/arm/exynos4210.c b/hw/arm/exynos4210.c
index 2e6423f74d..ea1364499d 100644
--- a/hw/arm/exynos4210.c
+++ b/hw/arm/exynos4210.c
@@ -582,7 +582,7 @@ static void exynos4210_realize(DeviceState *socdev, Error **errp)
     }
 
     /* Private memory region and Internal GIC */
-    qdev_prop_set_uint32(DEVICE(&s->a9mpcore), "num-cpu", EXYNOS4210_NCPUS);
+    qdev_prop_set_uint32(DEVICE(&s->a9mpcore), "num-cores", EXYNOS4210_NCPUS);
     busdev = SYS_BUS_DEVICE(&s->a9mpcore);
     sysbus_realize(busdev, &error_fatal);
     sysbus_mmio_map(busdev, 0, EXYNOS4210_SMP_PRIVATE_BASE_ADDR);
diff --git a/hw/arm/fsl-imx6.c b/hw/arm/fsl-imx6.c
index f6edbd7465..65c7c1a0f9 100644
--- a/hw/arm/fsl-imx6.c
+++ b/hw/arm/fsl-imx6.c
@@ -138,7 +138,7 @@ static void fsl_imx6_realize(DeviceState *dev, Error **errp)
         }
     }
 
-    object_property_set_int(OBJECT(&s->a9mpcore), "num-cpu", smp_cpus,
+    object_property_set_int(OBJECT(&s->a9mpcore), "num-cores", smp_cpus,
                             &error_abort);
 
     object_property_set_int(OBJECT(&s->a9mpcore), "num-irq",
diff --git a/hw/arm/fsl-imx6ul.c b/hw/arm/fsl-imx6ul.c
index 59032263cf..93908811c5 100644
--- a/hw/arm/fsl-imx6ul.c
+++ b/hw/arm/fsl-imx6ul.c
@@ -173,7 +173,7 @@ static void fsl_imx6ul_realize(DeviceState *dev, Error **errp)
     /*
      * A7MPCORE
      */
-    object_property_set_int(OBJECT(&s->a7mpcore), "num-cpu", 1, &error_abort);
+    object_property_set_int(OBJECT(&s->a7mpcore), "num-cores", 1, &error_abort);
     object_property_set_int(OBJECT(&s->a7mpcore), "num-irq",
                             FSL_IMX6UL_MAX_IRQ + GIC_INTERNAL, &error_abort);
     sysbus_realize(SYS_BUS_DEVICE(&s->a7mpcore), &error_abort);
diff --git a/hw/arm/fsl-imx7.c b/hw/arm/fsl-imx7.c
index a283dcb45f..8a3e9933c4 100644
--- a/hw/arm/fsl-imx7.c
+++ b/hw/arm/fsl-imx7.c
@@ -203,7 +203,7 @@ static void fsl_imx7_realize(DeviceState *dev, Error **errp)
     /*
      * A7MPCORE
      */
-    object_property_set_int(OBJECT(&s->a7mpcore), "num-cpu", smp_cpus,
+    object_property_set_int(OBJECT(&s->a7mpcore), "num-cores", smp_cpus,
                             &error_abort);
     object_property_set_int(OBJECT(&s->a7mpcore), "num-irq",
                             FSL_IMX7_MAX_IRQ + GIC_INTERNAL, &error_abort);
diff --git a/hw/arm/npcm7xx.c b/hw/arm/npcm7xx.c
index 15ff21d047..5b6e968fa9 100644
--- a/hw/arm/npcm7xx.c
+++ b/hw/arm/npcm7xx.c
@@ -491,7 +491,7 @@ static void npcm7xx_realize(DeviceState *dev, Error **errp)
     }
 
     /* A9MPCORE peripherals. Can only fail if we pass bad parameters here. */
-    object_property_set_int(OBJECT(&s->a9mpcore), "num-cpu", nc->num_cpus,
+    object_property_set_int(OBJECT(&s->a9mpcore), "num-cores", nc->num_cpus,
                             &error_abort);
     object_property_set_int(OBJECT(&s->a9mpcore), "num-irq", NPCM7XX_NUM_IRQ,
                             &error_abort);
diff --git a/hw/arm/realview.c b/hw/arm/realview.c
index a112a6b529..bb6bab12c8 100644
--- a/hw/arm/realview.c
+++ b/hw/arm/realview.c
@@ -187,7 +187,7 @@ static void realview_init(MachineState *machine,
 
     if (is_mpcore) {
         dev = qdev_new(is_pb ? TYPE_A9MPCORE_PRIV : "realview_mpcore");
-        qdev_prop_set_uint32(dev, "num-cpu", smp_cpus);
+        qdev_prop_set_uint32(dev, "num-cores", smp_cpus);
         busdev = SYS_BUS_DEVICE(dev);
         sysbus_realize_and_unref(busdev, &error_fatal);
         sysbus_mmio_map(busdev, 0, periphbase);
diff --git a/hw/cpu/a15mpcore.c b/hw/cpu/a15mpcore.c
index 128941eb50..16874426e1 100644
--- a/hw/cpu/a15mpcore.c
+++ b/hw/cpu/a15mpcore.c
@@ -63,7 +63,7 @@ static void a15mp_priv_realize(DeviceState *dev, Error **errp)
     }
 
     gicdev = DEVICE(&s->gic);
-    qdev_prop_set_uint32(gicdev, "num-cpu", s->num_cpu);
+    qdev_prop_set_uint32(gicdev, "num-cpu", c->num_cores);
     qdev_prop_set_uint32(gicdev, "num-irq", s->num_irq);
 
     if (!kvm_irqchip_in_kernel()) {
@@ -94,7 +94,7 @@ static void a15mp_priv_realize(DeviceState *dev, Error **errp)
     /* Wire the outputs from each CPU's generic timer to the
      * appropriate GIC PPI inputs
      */
-    for (i = 0; i < s->num_cpu; i++) {
+    for (i = 0; i < c->num_cores; i++) {
         DeviceState *cpudev = DEVICE(qemu_get_cpu(i));
         int ppibase = s->num_irq - 32 + i * 32;
         int irq;
@@ -114,7 +114,7 @@ static void a15mp_priv_realize(DeviceState *dev, Error **errp)
         }
         if (has_el2) {
             /* Connect the GIC maintenance interrupt to PPI ID 25 */
-            sysbus_connect_irq(SYS_BUS_DEVICE(gicdev), i + 4 * s->num_cpu,
+            sysbus_connect_irq(SYS_BUS_DEVICE(gicdev), i + 4 * c->num_cores,
                                qdev_get_gpio_in(gicdev, ppibase + 25));
         }
     }
@@ -139,17 +139,16 @@ static void a15mp_priv_realize(DeviceState *dev, Error **errp)
                                     sysbus_mmio_get_region(gicsbd, 2));
         memory_region_add_subregion(&c->container, 0x6000,
                                     sysbus_mmio_get_region(gicsbd, 3));
-        for (i = 0; i < s->num_cpu; i++) {
+        for (i = 0; i < c->num_cores; i++) {
             hwaddr base = 0x5000 + i * 0x200;
             MemoryRegion *mr = sysbus_mmio_get_region(gicsbd,
-                                                      4 + s->num_cpu + i);
+                                                      4 + c->num_cores + i);
             memory_region_add_subregion(&c->container, base, mr);
         }
     }
 }
 
 static Property a15mp_priv_properties[] = {
-    DEFINE_PROP_UINT32("num-cpu", A15MPPrivState, num_cpu, 1),
     /* The Cortex-A15MP may have anything from 0 to 224 external interrupt
      * IRQ lines (with another 32 internal). We default to 128+32, which
      * is the number provided by the Cortex-A15MP test chip in the
diff --git a/hw/cpu/a9mpcore.c b/hw/cpu/a9mpcore.c
index 08346b0049..9c138f4442 100644
--- a/hw/cpu/a9mpcore.c
+++ b/hw/cpu/a9mpcore.c
@@ -51,7 +51,6 @@ static void a9mp_priv_realize(DeviceState *dev, Error **errp)
     SysBusDevice *scubusdev, *gicbusdev, *gtimerbusdev, *mptimerbusdev,
                  *wdtbusdev;
     Error *local_err = NULL;
-    int i;
     bool has_el3;
     CPUState *cpu0;
     Object *cpuobj;
@@ -72,14 +71,14 @@ static void a9mp_priv_realize(DeviceState *dev, Error **errp)
     }
 
     scudev = DEVICE(&s->scu);
-    qdev_prop_set_uint32(scudev, "num-cpu", s->num_cpu);
+    qdev_prop_set_uint32(scudev, "num-cpu", c->num_cores);
     if (!sysbus_realize(SYS_BUS_DEVICE(&s->scu), errp)) {
         return;
     }
     scubusdev = SYS_BUS_DEVICE(&s->scu);
 
     gicdev = DEVICE(&s->gic);
-    qdev_prop_set_uint32(gicdev, "num-cpu", s->num_cpu);
+    qdev_prop_set_uint32(gicdev, "num-cpu", c->num_cores);
     qdev_prop_set_uint32(gicdev, "num-irq", s->num_irq);
     qdev_prop_set_uint32(gicdev, "num-priority-bits",
                          A9_GIC_NUM_PRIORITY_BITS);
@@ -103,21 +102,21 @@ static void a9mp_priv_realize(DeviceState *dev, Error **errp)
     qdev_init_gpio_in(dev, a9mp_priv_set_irq, s->num_irq - 32);
 
     gtimerdev = DEVICE(&s->gtimer);
-    qdev_prop_set_uint32(gtimerdev, "num-cpu", s->num_cpu);
+    qdev_prop_set_uint32(gtimerdev, "num-cpu", c->num_cores);
     if (!sysbus_realize(SYS_BUS_DEVICE(&s->gtimer), errp)) {
         return;
     }
     gtimerbusdev = SYS_BUS_DEVICE(&s->gtimer);
 
     mptimerdev = DEVICE(&s->mptimer);
-    qdev_prop_set_uint32(mptimerdev, "num-cpu", s->num_cpu);
+    qdev_prop_set_uint32(mptimerdev, "num-cpu", c->num_cores);
     if (!sysbus_realize(SYS_BUS_DEVICE(&s->mptimer), errp)) {
         return;
     }
     mptimerbusdev = SYS_BUS_DEVICE(&s->mptimer);
 
     wdtdev = DEVICE(&s->wdt);
-    qdev_prop_set_uint32(wdtdev, "num-cpu", s->num_cpu);
+    qdev_prop_set_uint32(wdtdev, "num-cpu", c->num_cores);
     if (!sysbus_realize(SYS_BUS_DEVICE(&s->wdt), errp)) {
         return;
     }
@@ -153,7 +152,7 @@ static void a9mp_priv_realize(DeviceState *dev, Error **errp)
      * For each core the global timer is PPI 27, the private
      * timer is PPI 29 and the watchdog PPI 30.
      */
-    for (i = 0; i < s->num_cpu; i++) {
+    for (unsigned i = 0; i < c->num_cores; i++) {
         int ppibase = (s->num_irq - 32) + i * 32;
         sysbus_connect_irq(gtimerbusdev, i,
                            qdev_get_gpio_in(gicdev, ppibase + 27));
@@ -165,7 +164,6 @@ static void a9mp_priv_realize(DeviceState *dev, Error **errp)
 }
 
 static Property a9mp_priv_properties[] = {
-    DEFINE_PROP_UINT32("num-cpu", A9MPPrivState, num_cpu, 1),
     /* The Cortex-A9MP may have anything from 0 to 224 external interrupt
      * IRQ lines (with another 32 internal). We default to 64+32, which
      * is the number provided by the Cortex-A9MP test chip in the
diff --git a/hw/cpu/arm11mpcore.c b/hw/cpu/arm11mpcore.c
index 74f44434de..67c96a3a7c 100644
--- a/hw/cpu/arm11mpcore.c
+++ b/hw/cpu/arm11mpcore.c
@@ -132,7 +132,8 @@ static void mpcore_priv_initfn(Object *obj)
 }
 
 static Property mpcore_priv_properties[] = {
-    DEFINE_PROP_UINT32("num-cpu", ARM11MPCorePriveState, num_cpu, 1),
+    DEFINE_PROP_UINT32("num-cores", ARM11MPCorePriveState, num_cpu, 1),
+    DEFINE_PROP_UINT32("num-cpu", ARM11MPCorePriveState, num_cpu, 1), /* alias */
     /* The ARM11 MPCORE TRM says the on-chip controller may have
      * anything from 0 to 224 external interrupt IRQ lines (with another
      * 32 internal). We default to 32+32, which is the number provided by
diff --git a/hw/cpu/cortex_mpcore.c b/hw/cpu/cortex_mpcore.c
index 0c12f99610..d7ea633e4e 100644
--- a/hw/cpu/cortex_mpcore.c
+++ b/hw/cpu/cortex_mpcore.c
@@ -8,6 +8,7 @@
 
 #include "qemu/osdep.h"
 #include "qapi/error.h"
+#include "hw/qdev-properties.h"
 #include "hw/cpu/cortex_mpcore.h"
 
 static void cortex_mpcore_priv_instance_init(Object *obj)
@@ -22,6 +23,21 @@ static void cortex_mpcore_priv_instance_init(Object *obj)
     sysbus_init_mmio(sbd, &s->container);
 }
 
+static Property cortex_mpcore_priv_properties[] = {
+    DEFINE_PROP_UINT32("num-cores", CortexMPPrivState, num_cores, 1),
+    DEFINE_PROP_UINT32("num-cpu", CortexMPPrivState, num_cores, 1), /* alias */
+
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void cortex_mpcore_priv_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    device_class_set_props(dc, cortex_mpcore_priv_properties);
+    /* We currently have no saveable state */
+}
+
 static const TypeInfo cortex_mpcore_types[] = {
     {
         .name           = TYPE_CORTEX_MPCORE_PRIV,
@@ -29,6 +45,7 @@ static const TypeInfo cortex_mpcore_types[] = {
         .instance_size  = sizeof(CortexMPPrivState),
         .instance_init  = cortex_mpcore_priv_instance_init,
         .class_size     = sizeof(CortexMPPrivClass),
+        .class_init     = cortex_mpcore_priv_class_init,
         .abstract       = true,
     },
 };
diff --git a/hw/cpu/realview_mpcore.c b/hw/cpu/realview_mpcore.c
index b140888618..e985d230e0 100644
--- a/hw/cpu/realview_mpcore.c
+++ b/hw/cpu/realview_mpcore.c
@@ -98,7 +98,8 @@ static void mpcore_rirq_init(Object *obj)
     int i;
 
     object_initialize_child(obj, "a11priv", &s->priv, TYPE_ARM11MPCORE_PRIV);
-    object_property_add_alias(obj, "num-cpu", OBJECT(&s->priv), "num-cpu");
+    object_property_add_alias(obj, "num-cores", OBJECT(&s->priv), "num-cores");
+    object_property_add_alias(obj, "num-cpu", OBJECT(&s->priv), "num-cores");
     privbusdev = SYS_BUS_DEVICE(&s->priv);
     sysbus_init_mmio(sbd, sysbus_mmio_get_region(privbusdev, 0));
 
