cpu: Abstract CPU core type

Add an abstract CPU core type that could be used by machines that want
to define and hotplug CPUs in core granularity.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
               [Integer core property]
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
[dwg: changed property names to 'core-id' and 'nr-threads']
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

hw/cpu/Makefile.objs

@@ -2,4 +2,5 @@ obj-$(CONFIG_ARM11MPCORE) += arm11mpcore.o
 obj-$(CONFIG_REALVIEW) += realview_mpcore.o
 obj-$(CONFIG_A9MPCORE) += a9mpcore.o
 obj-$(CONFIG_A15MPCORE) += a15mpcore.o
+obj-y += core.o
 

hw/cpu/core.c

@@ -0,0 +1,88 @@
+/*
+ * CPU core abstract device
+ *
+ * Copyright (C) 2016 Bharata B Rao <bharata@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+#include "hw/cpu/core.h"
+#include "qapi/visitor.h"
+#include "qapi/error.h"
+#include "sysemu/cpus.h"
+
+static void core_prop_get_core_id(Object *obj, Visitor *v, const char *name,
+                                  void *opaque, Error **errp)
+{
+    CPUCore *core = CPU_CORE(obj);
+    int64_t value = core->core_id;
+
+    visit_type_int(v, name, &value, errp);
+}
+
+static void core_prop_set_core_id(Object *obj, Visitor *v, const char *name,
+                                  void *opaque, Error **errp)
+{
+    CPUCore *core = CPU_CORE(obj);
+    Error *local_err = NULL;
+    int64_t value;
+
+    visit_type_int(v, name, &value, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return;
+    }
+
+    core->core_id = value;
+}
+
+static void core_prop_get_nr_threads(Object *obj, Visitor *v, const char *name,
+                                     void *opaque, Error **errp)
+{
+    CPUCore *core = CPU_CORE(obj);
+    int64_t value = core->nr_threads;
+
+    visit_type_int(v, name, &value, errp);
+}
+
+static void core_prop_set_nr_threads(Object *obj, Visitor *v, const char *name,
+                                     void *opaque, Error **errp)
+{
+    CPUCore *core = CPU_CORE(obj);
+    Error *local_err = NULL;
+    int64_t value;
+
+    visit_type_int(v, name, &value, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return;
+    }
+
+    core->nr_threads = value;
+}
+
+static void cpu_core_instance_init(Object *obj)
+{
+    CPUCore *core = CPU_CORE(obj);
+
+    object_property_add(obj, "core-id", "int", core_prop_get_core_id,
+                        core_prop_set_core_id, NULL, NULL, NULL);
+    object_property_add(obj, "nr-threads", "int", core_prop_get_nr_threads,
+                        core_prop_set_nr_threads, NULL, NULL, NULL);
+    core->nr_threads = smp_threads;
+}
+
+static const TypeInfo cpu_core_type_info = {
+    .name = TYPE_CPU_CORE,
+    .parent = TYPE_DEVICE,
+    .abstract = true,
+    .instance_size = sizeof(CPUCore),
+    .instance_init = cpu_core_instance_init,
+};
+
+static void cpu_core_register_types(void)
+{
+    type_register_static(&cpu_core_type_info);
+}
+
+type_init(cpu_core_register_types)

include/hw/cpu/core.h

@@ -0,0 +1,31 @@
+/*
+ * CPU core abstract device
+ *
+ * Copyright (C) 2016 Bharata B Rao <bharata@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+#ifndef HW_CPU_CORE_H
+#define HW_CPU_CORE_H
+
+#include "qemu/osdep.h"
+#include "hw/qdev.h"
+
+#define TYPE_CPU_CORE "cpu-core"
+
+#define CPU_CORE(obj) \
+    OBJECT_CHECK(CPUCore, (obj), TYPE_CPU_CORE)
+
+typedef struct CPUCore {
+    /*< private >*/
+    DeviceState parent_obj;
+
+    /*< public >*/
+    int core_id;
+    int nr_threads;
+} CPUCore;
+
+#define CPU_CORE_PROP_CORE_ID "core-id"
+
+#endif