diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index baefc7bd279c..89e61b976c60 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -199,7 +199,6 @@ static int spapr_fixup_cpu_dt(void *fdt, sPAPRMachineState *spapr)
     int ret = 0, offset, cpus_offset;
     CPUState *cs;
     char cpu_model[32];
-    int smt = kvmppc_smt_threads();
     uint32_t pft_size_prop[] = {0, cpu_to_be32(spapr->htab_shift)};
 
     CPU_FOREACH(cs) {
@@ -207,7 +206,7 @@ static int spapr_fixup_cpu_dt(void *fdt, sPAPRMachineState *spapr)
         DeviceClass *dc = DEVICE_GET_CLASS(cs);
         int index = ppc_get_vcpu_dt_id(cpu);
 
-        if ((index % smt) != 0) {
+        if (!spapr_core_dt_id_is_valid(index)) {
             continue;
         }
 
@@ -735,7 +734,6 @@ static void spapr_populate_cpus_dt_node(void *fdt, sPAPRMachineState *spapr)
     CPUState *cs;
     int cpus_offset;
     char *nodename;
-    int smt = kvmppc_smt_threads();
 
     cpus_offset = fdt_add_subnode(fdt, 0, "cpus");
     _FDT(cpus_offset);
@@ -753,7 +751,7 @@ static void spapr_populate_cpus_dt_node(void *fdt, sPAPRMachineState *spapr)
         DeviceClass *dc = DEVICE_GET_CLASS(cs);
         int offset;
 
-        if ((index % smt) != 0) {
+        if (!spapr_core_dt_id_is_valid(index)) {
             continue;
         }
 
@@ -1822,7 +1820,7 @@ static void ppc_spapr_init(MachineState *machine)
 
         spapr->cores = g_new0(Object *, spapr_max_cores);
         for (i = 0; i < spapr_max_cores; i++) {
-            int core_dt_id = i * smt;
+            int core_dt_id = spapr_core_index_to_dt_id(i);
             sPAPRDRConnector *drc =
                 spapr_dr_connector_new(OBJECT(spapr),
                                        SPAPR_DR_CONNECTOR_TYPE_CPU, core_dt_id);
@@ -2386,7 +2384,6 @@ static HotpluggableCPUList *spapr_query_hotpluggable_cpus(MachineState *machine)
     HotpluggableCPUList *head = NULL;
     sPAPRMachineState *spapr = SPAPR_MACHINE(machine);
     int spapr_max_cores = max_cpus / smp_threads;
-    int smt = kvmppc_smt_threads();
 
     for (i = 0; i < spapr_max_cores; i++) {
         HotpluggableCPUList *list_item = g_new0(typeof(*list_item), 1);
@@ -2396,7 +2393,7 @@ static HotpluggableCPUList *spapr_query_hotpluggable_cpus(MachineState *machine)
         cpu_item->type = spapr_get_cpu_core_type(machine->cpu_model);
         cpu_item->vcpus_count = smp_threads;
         cpu_props->has_core_id = true;
-        cpu_props->core_id = i * smt;
+        cpu_props->core_id = spapr_core_index_to_dt_id(i);
         /* TODO: add 'has_node/node' here to describe
            to which node core belongs */
 
diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c
index e3a3024baf32..b104778350df 100644
--- a/hw/ppc/spapr_cpu_core.c
+++ b/hw/ppc/spapr_cpu_core.c
@@ -103,7 +103,6 @@ static void spapr_core_release(DeviceState *dev, void *opaque)
     size_t size = object_type_get_instance_size(typename);
     sPAPRMachineState *spapr = SPAPR_MACHINE(qdev_get_machine());
     CPUCore *cc = CPU_CORE(dev);
-    int smt = kvmppc_smt_threads();
     int i;
 
     for (i = 0; i < cc->nr_threads; i++) {
@@ -117,7 +116,7 @@ static void spapr_core_release(DeviceState *dev, void *opaque)
         object_unparent(obj);
     }
 
-    spapr->cores[cc->core_id / smt] = NULL;
+    spapr->cores[spapr_dt_id_to_core_index(cc->core_id)] = NULL;
 
     g_free(sc->threads);
     object_unparent(OBJECT(dev));
@@ -160,10 +159,9 @@ void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
     void *fdt = NULL;
     int fdt_offset = 0;
     int index;
-    int smt = kvmppc_smt_threads();
 
     drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_CPU, cc->core_id);
-    index = cc->core_id / smt;
+    index = spapr_dt_id_to_core_index(cc->core_id);
     spapr->cores[index] = OBJECT(dev);
 
     if (!smc->dr_cpu_enabled) {
@@ -217,7 +215,6 @@ void spapr_core_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
     sPAPRMachineState *spapr = SPAPR_MACHINE(OBJECT(hotplug_dev));
     int spapr_max_cores = max_cpus / smp_threads;
     int index;
-    int smt = kvmppc_smt_threads();
     Error *local_err = NULL;
     CPUCore *cc = CPU_CORE(dev);
     char *base_core_type = spapr_get_cpu_core_type(machine->cpu_model);
@@ -238,12 +235,12 @@ void spapr_core_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
         goto out;
     }
 
-    if (cc->core_id % smt) {
+    if (!spapr_core_dt_id_is_valid(cc->core_id)) {
         error_setg(&local_err, "invalid core id %d\n", cc->core_id);
         goto out;
     }
 
-    index = cc->core_id / smt;
+    index = spapr_dt_id_to_core_index(cc->core_id);
     if (index < 0 || index >= spapr_max_cores) {
         error_setg(&local_err, "core id %d out of range", cc->core_id);
         goto out;
@@ -331,6 +328,21 @@ static void spapr_cpu_core_class_init(ObjectClass *oc, void *data)
     dc->realize = spapr_cpu_core_realize;
 }
 
+unsigned spapr_core_index_to_dt_id(unsigned index)
+{
+    return index * kvmppc_smt_threads();
+}
+
+unsigned spapr_dt_id_to_core_index(unsigned dt_id)
+{
+    return dt_id / kvmppc_smt_threads();
+}
+
+unsigned spapr_dt_id_to_thread_index(unsigned dt_id)
+{
+    return dt_id % kvmppc_smt_threads();
+}
+
 /*
  * instance_init routines from different flavours of sPAPR CPU cores.
  */
diff --git a/include/hw/ppc/spapr_cpu_core.h b/include/hw/ppc/spapr_cpu_core.h
index 1c9b3195cce9..be7be91308ce 100644
--- a/include/hw/ppc/spapr_cpu_core.h
+++ b/include/hw/ppc/spapr_cpu_core.h
@@ -33,4 +33,13 @@ void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
                      Error **errp);
 void spapr_core_unplug(HotplugHandler *hotplug_dev, DeviceState *dev,
                        Error **errp);
+
+unsigned spapr_core_index_to_dt_id(unsigned index);
+unsigned spapr_dt_id_to_core_index(unsigned dt_id);
+unsigned spapr_dt_id_to_thread_index(unsigned dt_id);
+
+static inline bool spapr_core_dt_id_is_valid(unsigned dt_id)
+{
+    return spapr_dt_id_to_thread_index(dt_id) == 0;
+}
 #endif
