hw/core/bus.c

   1 /*
   2  *  Dynamic device configuration and creation -- buses.
   3  *
   4  *  Copyright (c) 2009 CodeSourcery
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "qemu/osdep.h"
  21 #include "qemu-common.h"
  22 #include "hw/qdev.h"
  23 #include "qapi/error.h"
  24
  25 static void qbus_set_hotplug_handler_internal(BusState *bus, Object *handler,
  26                                               Error **errp)
  27 {
  28
  29     object_property_set_link(OBJECT(bus), OBJECT(handler),
  30                              QDEV_HOTPLUG_HANDLER_PROPERTY, errp);
  31 }
  32
  33 void qbus_set_hotplug_handler(BusState *bus, DeviceState *handler, Error **errp)
  34 {
  35     qbus_set_hotplug_handler_internal(bus, OBJECT(handler), errp);
  36 }
  37
  38 void qbus_set_bus_hotplug_handler(BusState *bus, Error **errp)
  39 {
  40     qbus_set_hotplug_handler_internal(bus, OBJECT(bus), errp);
  41 }
  42
  43 int qbus_walk_children(BusState *bus,
  44                        qdev_walkerfn *pre_devfn, qbus_walkerfn *pre_busfn,
  45                        qdev_walkerfn *post_devfn, qbus_walkerfn *post_busfn,
  46                        void *opaque)
  47 {
  48     BusChild *kid;
  49     int err;
  50
  51     if (pre_busfn) {
  52         err = pre_busfn(bus, opaque);
  53         if (err) {
  54             return err;
  55         }
  56     }
  57
  58     QTAILQ_FOREACH(kid, &bus->children, sibling) {
  59         err = qdev_walk_children(kid->child,
  60                                  pre_devfn, pre_busfn,
  61                                  post_devfn, post_busfn, opaque);
  62         if (err < 0) {
  63             return err;
  64         }
  65     }
  66
  67     if (post_busfn) {
  68         err = post_busfn(bus, opaque);
  69         if (err) {
  70             return err;
  71         }
  72     }
  73
  74     return 0;
  75 }
  76
  77 static void qbus_realize(BusState *bus, DeviceState *parent, const char *name)
  78 {
  79     const char *typename = object_get_typename(OBJECT(bus));
  80     BusClass *bc;
  81     int i, bus_id;
  82
  83     bus->parent = parent;
  84
  85     if (name) {
  86         bus->name = g_strdup(name);
  87     } else if (bus->parent && bus->parent->id) {
  88         /* parent device has id -> use it plus parent-bus-id for bus name */
  89         bus_id = bus->parent->num_child_bus;
  90         bus->name = g_strdup_printf("%s.%d", bus->parent->id, bus_id);
  91     } else {
  92         /* no id -> use lowercase bus type plus global bus-id for bus name */
  93         bc = BUS_GET_CLASS(bus);
  94         bus_id = bc->automatic_ids++;
  95         bus->name = g_strdup_printf("%s.%d", typename, bus_id);
  96         for (i = 0; bus->name[i]; i++) {
  97             bus->name[i] = qemu_tolower(bus->name[i]);
  98         }
  99     }
 100
 101     if (bus->parent) {
 102         QLIST_INSERT_HEAD(&bus->parent->child_bus, bus, sibling);
 103         bus->parent->num_child_bus++;
 104         object_property_add_child(OBJECT(bus->parent), bus->name, OBJECT(bus), NULL);
 105         object_unref(OBJECT(bus));
 106     } else if (bus != sysbus_get_default()) {
 107         /* TODO: once all bus devices are qdevified,
 108            only reset handler for main_system_bus should be registered here. */
 109         qemu_register_reset(qbus_reset_all_fn, bus);
 110     }
 111 }
 112
 113 static void bus_unparent(Object *obj)
 114 {
 115     BusState *bus = BUS(obj);
 116     BusChild *kid;
 117
 118     while ((kid = QTAILQ_FIRST(&bus->children)) != NULL) {
 119         DeviceState *dev = kid->child;
 120         object_unparent(OBJECT(dev));
 121     }
 122     if (bus->parent) {
 123         QLIST_REMOVE(bus, sibling);
 124         bus->parent->num_child_bus--;
 125         bus->parent = NULL;
 126     } else {
 127         assert(bus != sysbus_get_default()); /* main_system_bus is never freed */
 128         qemu_unregister_reset(qbus_reset_all_fn, bus);
 129     }
 130 }
 131
 132 void qbus_create_inplace(void *bus, size_t size, const char *typename,
 133                          DeviceState *parent, const char *name)
 134 {
 135     object_initialize(bus, size, typename);
 136     qbus_realize(bus, parent, name);
 137 }
 138
 139 BusState *qbus_create(const char *typename, DeviceState *parent, const char *name)
 140 {
 141     BusState *bus;
 142
 143     bus = BUS(object_new(typename));
 144     qbus_realize(bus, parent, name);
 145
 146     return bus;
 147 }
 148
 149 static bool bus_get_realized(Object *obj, Error **errp)
 150 {
 151     BusState *bus = BUS(obj);
 152
 153     return bus->realized;
 154 }
 155
 156 static void bus_set_realized(Object *obj, bool value, Error **errp)
 157 {
 158     BusState *bus = BUS(obj);
 159     BusClass *bc = BUS_GET_CLASS(bus);
 160     BusChild *kid;
 161     Error *local_err = NULL;
 162
 163     if (value && !bus->realized) {
 164         if (bc->realize) {
 165             bc->realize(bus, &local_err);
 166         }
 167
 168         /* TODO: recursive realization */
 169     } else if (!value && bus->realized) {
 170         QTAILQ_FOREACH(kid, &bus->children, sibling) {
 171             DeviceState *dev = kid->child;
 172             object_property_set_bool(OBJECT(dev), false, "realized",
 173                                      &local_err);
 174             if (local_err != NULL) {
 175                 break;
 176             }
 177         }
 178         if (bc->unrealize && local_err == NULL) {
 179             bc->unrealize(bus, &local_err);
 180         }
 181     }
 182
 183     if (local_err != NULL) {
 184         error_propagate(errp, local_err);
 185         return;
 186     }
 187
 188     bus->realized = value;
 189 }
 190
 191 static void qbus_initfn(Object *obj)
 192 {
 193     BusState *bus = BUS(obj);
 194
 195     QTAILQ_INIT(&bus->children);
 196     object_property_add_link(obj, QDEV_HOTPLUG_HANDLER_PROPERTY,
 197                              TYPE_HOTPLUG_HANDLER,
 198                              (Object **)&bus->hotplug_handler,
 199                              object_property_allow_set_link,
 200                              OBJ_PROP_LINK_UNREF_ON_RELEASE,
 201                              NULL);
 202     object_property_add_bool(obj, "realized",
 203                              bus_get_realized, bus_set_realized, NULL);
 204 }
 205
 206 static char *default_bus_get_fw_dev_path(DeviceState *dev)
 207 {
 208     return g_strdup(object_get_typename(OBJECT(dev)));
 209 }
 210
 211 static void bus_class_init(ObjectClass *class, void *data)
 212 {
 213     BusClass *bc = BUS_CLASS(class);
 214
 215     class->unparent = bus_unparent;
 216     bc->get_fw_dev_path = default_bus_get_fw_dev_path;
 217 }
 218
 219 static void qbus_finalize(Object *obj)
 220 {
 221     BusState *bus = BUS(obj);
 222
 223     g_free(bus->name);
 224 }
 225
 226 static const TypeInfo bus_info = {
 227     .name = TYPE_BUS,
 228     .parent = TYPE_OBJECT,
 229     .instance_size = sizeof(BusState),
 230     .abstract = true,
 231     .class_size = sizeof(BusClass),
 232     .instance_init = qbus_initfn,
 233     .instance_finalize = qbus_finalize,
 234     .class_init = bus_class_init,
 235 };
 236
 237 static void bus_register_types(void)
 238 {
 239     type_register_static(&bus_info);
 240 }
 241
 242 type_init(bus_register_types)