xref: /openbmc/qemu/hw/s390x/ap-bridge.c (revision b097ba37)
1 /*
2  * ap bridge
3  *
4  * Copyright 2018 IBM Corp.
5  *
6  * This work is licensed under the terms of the GNU GPL, version 2 or (at
7  * your option) any later version. See the COPYING file in the top-level
8  * directory.
9  */
10 #include "qemu/osdep.h"
11 #include "qapi/error.h"
12 #include "hw/sysbus.h"
13 #include "qemu/bitops.h"
14 #include "hw/s390x/ap-bridge.h"
15 #include "cpu.h"
16 
17 static char *ap_bus_get_dev_path(DeviceState *dev)
18 {
19     /* at most one */
20     return g_strdup_printf("/1");
21 }
22 
23 static void ap_bus_class_init(ObjectClass *oc, void *data)
24 {
25     BusClass *k = BUS_CLASS(oc);
26 
27     k->get_dev_path = ap_bus_get_dev_path;
28     /* More than one ap device does not make sense */
29     k->max_dev = 1;
30 }
31 
32 static const TypeInfo ap_bus_info = {
33     .name = TYPE_AP_BUS,
34     .parent = TYPE_BUS,
35     .instance_size = 0,
36     .class_init = ap_bus_class_init,
37 };
38 
39 void s390_init_ap(void)
40 {
41     DeviceState *dev;
42     BusState *bus;
43 
44     /* If no AP instructions then no need for AP bridge */
45     if (!s390_has_feat(S390_FEAT_AP)) {
46         return;
47     }
48 
49     /* Create bridge device */
50     dev = qdev_create(NULL, TYPE_AP_BRIDGE);
51     object_property_add_child(qdev_get_machine(), TYPE_AP_BRIDGE,
52                               OBJECT(dev), NULL);
53     qdev_init_nofail(dev);
54 
55     /* Create bus on bridge device */
56     bus = qbus_create(TYPE_AP_BUS, dev, TYPE_AP_BUS);
57 
58     /* Enable hotplugging */
59     qbus_set_hotplug_handler(bus, OBJECT(dev), &error_abort);
60  }
61 
62 static void ap_bridge_class_init(ObjectClass *oc, void *data)
63 {
64     DeviceClass *dc = DEVICE_CLASS(oc);
65     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(oc);
66 
67     hc->unplug = qdev_simple_device_unplug_cb;
68     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
69 }
70 
71 static const TypeInfo ap_bridge_info = {
72     .name          = TYPE_AP_BRIDGE,
73     .parent        = TYPE_SYS_BUS_DEVICE,
74     .instance_size = 0,
75     .class_init    = ap_bridge_class_init,
76     .interfaces = (InterfaceInfo[]) {
77         { TYPE_HOTPLUG_HANDLER },
78         { }
79     }
80 };
81 
82 static void ap_register(void)
83 {
84     type_register_static(&ap_bridge_info);
85     type_register_static(&ap_bus_info);
86 }
87 
88 type_init(ap_register)
89