diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index d4afe7d..eae1305 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -102,54 +102,16 @@ static void virtio_ccw_register_hcalls(void)
 
 static void ccw_init(MachineState *machine)
 {
-    ram_addr_t my_ram_size = machine->ram_size;
     MemoryRegion *sysmem = get_system_memory();
     MemoryRegion *ram = g_new(MemoryRegion, 1);
-    sclpMemoryHotplugDev *mhd = init_sclp_memory_hotplug_dev();
     int ret;
     VirtualCssBus *css_bus;
     DeviceState *dev;
-    ram_addr_t pad_size = 0;
-    ram_addr_t maxmem = machine->maxram_size;
-    ram_addr_t standby_mem_size = maxmem - my_ram_size;
-    uint64_t kvm_limit;
-
-    /* The storage increment size is a multiple of 1M and is a power of 2.
-     * The number of storage increments must be MAX_STORAGE_INCREMENTS or fewer.
-     * The variable 'mhd->increment_size' is an exponent of 2 that can be
-     * used to calculate the size (in bytes) of an increment. */
-    mhd->increment_size = 20;
-    while ((my_ram_size >> mhd->increment_size) > MAX_STORAGE_INCREMENTS) {
-        mhd->increment_size++;
-    }
-    while ((standby_mem_size >> mhd->increment_size) > MAX_STORAGE_INCREMENTS) {
-        mhd->increment_size++;
-    }
 
-    /* The core and standby memory areas need to be aligned with
-     * the increment size.  In effect, this can cause the
-     * user-specified memory size to be rounded down to align
-     * with the nearest increment boundary. */
-    standby_mem_size = standby_mem_size >> mhd->increment_size
-                                        << mhd->increment_size;
-    my_ram_size = my_ram_size >> mhd->increment_size
-                              << mhd->increment_size;
-
-    /* let's propagate the changed ram size into the global variable. */
-    ram_size = my_ram_size;
-    machine->maxram_size = my_ram_size + standby_mem_size;
-
-    ret = s390_set_memory_limit(machine->maxram_size, &kvm_limit);
-    if (ret == -E2BIG) {
-        hw_error("qemu: host supports a maximum of %" PRIu64 " GB",
-                 kvm_limit >> 30);
-    } else if (ret) {
-        hw_error("qemu: setting the guest size failed");
-    }
+    s390_sclp_init();
 
     /* get a BUS */
     css_bus = virtual_css_bus_init();
-    s390_sclp_init();
     s390_init_ipl_dev(machine->kernel_filename, machine->kernel_cmdline,
                       machine->initrd_filename, "s390-ccw.img", true);
     s390_flic_init();
@@ -163,21 +125,11 @@ static void ccw_init(MachineState *machine)
     virtio_ccw_register_hcalls();
 
     /* allocate RAM for core */
-    memory_region_init_ram(ram, NULL, "s390.ram", my_ram_size, &error_abort);
+    memory_region_init_ram(ram, NULL, "s390.ram", machine->ram_size,
+                           &error_abort);
     vmstate_register_ram_global(ram);
     memory_region_add_subregion(sysmem, 0, ram);
 
-    /* If the size of ram is not on a MEM_SECTION_SIZE boundary,
-       calculate the pad size necessary to force this boundary. */
-    if (standby_mem_size) {
-        if (my_ram_size % MEM_SECTION_SIZE) {
-            pad_size = MEM_SECTION_SIZE - my_ram_size % MEM_SECTION_SIZE;
-        }
-        my_ram_size += standby_mem_size + pad_size;
-        mhd->pad_size = pad_size;
-        mhd->standby_mem_size = standby_mem_size;
-    }
-
     /* Initialize storage key device */
     s390_skeys_init();
 
diff --git a/hw/s390x/s390-virtio.c b/hw/s390x/s390-virtio.c
index b0f339e..c8e4737 100644
--- a/hw/s390x/s390-virtio.c
+++ b/hw/s390x/s390-virtio.c
@@ -261,10 +261,9 @@ int gtod_load(QEMUFile *f, void *opaque, int version_id)
 /* PC hardware initialisation */
 static void s390_init(MachineState *machine)
 {
-    ram_addr_t my_ram_size = machine->ram_size;
+    ram_addr_t my_ram_size;
     MemoryRegion *sysmem = get_system_memory();
     MemoryRegion *ram = g_new(MemoryRegion, 1);
-    int increment_size = 20;
     void *virtio_region;
     hwaddr virtio_region_len;
     hwaddr virtio_region_start;
@@ -273,22 +272,11 @@ static void s390_init(MachineState *machine)
         error_report("Memory hotplug not supported by the selected machine.");
         exit(EXIT_FAILURE);
     }
-    /*
-     * The storage increment size is a multiple of 1M and is a power of 2.
-     * The number of storage increments must be MAX_STORAGE_INCREMENTS or
-     * fewer.
-     */
-    while ((my_ram_size >> increment_size) > MAX_STORAGE_INCREMENTS) {
-        increment_size++;
-    }
-    my_ram_size = my_ram_size >> increment_size << increment_size;
-
-    /* let's propagate the changed ram size into the global variable. */
-    ram_size = my_ram_size;
+    s390_sclp_init();
+    my_ram_size = machine->ram_size;
 
     /* get a BUS */
     s390_bus = s390_virtio_bus_init(&my_ram_size);
-    s390_sclp_init();
     s390_init_ipl_dev(machine->kernel_filename, machine->kernel_cmdline,
                       machine->initrd_filename, ZIPL_FILENAME, false);
     s390_flic_init();
diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c
index b1a62c7..ac582e8 100644
--- a/hw/s390x/sclp.c
+++ b/hw/s390x/sclp.c
@@ -470,20 +470,80 @@ void s390_sclp_init(void)
 
 static void sclp_realize(DeviceState *dev, Error **errp)
 {
+    MachineState *machine = MACHINE(qdev_get_machine());
     SCLPDevice *sclp = SCLP(dev);
     Error *l_err = NULL;
+    uint64_t hw_limit;
+    int ret;
 
     object_property_set_bool(OBJECT(sclp->event_facility), true, "realized",
                              &l_err);
     if (l_err) {
         goto error;
     }
+
+    ret = s390_set_memory_limit(machine->maxram_size, &hw_limit);
+    if (ret == -E2BIG) {
+        error_setg(&l_err, "qemu: host supports a maximum of %" PRIu64 " GB",
+                   hw_limit >> 30);
+        goto error;
+    } else if (ret) {
+        error_setg(&l_err, "qemu: setting the guest size failed");
+        goto error;
+    }
     return;
 error:
     assert(l_err);
     error_propagate(errp, l_err);
 }
 
+static void sclp_memory_init(SCLPDevice *sclp)
+{
+    MachineState *machine = MACHINE(qdev_get_machine());
+    ram_addr_t initial_mem = machine->ram_size;
+    ram_addr_t max_mem = machine->maxram_size;
+    ram_addr_t standby_mem = max_mem - initial_mem;
+    ram_addr_t pad_mem = 0;
+    int increment_size = 20;
+
+    /* The storage increment size is a multiple of 1M and is a power of 2.
+     * The number of storage increments must be MAX_STORAGE_INCREMENTS or fewer.
+     * The variable 'increment_size' is an exponent of 2 that can be
+     * used to calculate the size (in bytes) of an increment. */
+    while ((initial_mem >> increment_size) > MAX_STORAGE_INCREMENTS) {
+        increment_size++;
+    }
+    if (machine->ram_slots) {
+        while ((standby_mem >> increment_size) > MAX_STORAGE_INCREMENTS) {
+            increment_size++;
+        }
+    }
+
+    /* The core and standby memory areas need to be aligned with
+     * the increment size.  In effect, this can cause the
+     * user-specified memory size to be rounded down to align
+     * with the nearest increment boundary. */
+    initial_mem = initial_mem >> increment_size << increment_size;
+    standby_mem = standby_mem >> increment_size << increment_size;
+
+    /* If the size of ram is not on a MEM_SECTION_SIZE boundary,
+       calculate the pad size necessary to force this boundary. */
+    if (machine->ram_slots && standby_mem) {
+        sclpMemoryHotplugDev *mhd = init_sclp_memory_hotplug_dev();
+
+        if (initial_mem % MEM_SECTION_SIZE) {
+            pad_mem = MEM_SECTION_SIZE - initial_mem % MEM_SECTION_SIZE;
+        }
+        mhd->increment_size = increment_size;
+        mhd->pad_size = pad_mem;
+        mhd->standby_mem_size = standby_mem;
+    }
+    machine->ram_size = initial_mem;
+    machine->maxram_size = initial_mem + pad_mem + standby_mem;
+    /* let's propagate the changed ram size into the global variable. */
+    ram_size = initial_mem;
+}
+
 static void sclp_init(Object *obj)
 {
     SCLPDevice *sclp = SCLP(obj);
@@ -495,6 +555,8 @@ static void sclp_init(Object *obj)
     qdev_set_parent_bus(DEVICE(new), sysbus_get_default());
     object_unref(new);
     sclp->event_facility = EVENT_FACILITY(new);
+
+    sclp_memory_init(sclp);
 }
 
 static void sclp_class_init(ObjectClass *oc, void *data)
