xref: /qemu/hw/s390x/css-bridge.c (revision 513823e7521a09ed7ad1e32e6454bac3b2cbf52d)
1 /*
2  * css bridge implementation
3  *
4  * Copyright 2012,2016 IBM Corp.
5  * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
6  *            Pierre Morel <pmorel@linux.vnet.ibm.com>
7  *
8  * This work is licensed under the terms of the GNU GPL, version 2 or (at
9  * your option) any later version. See the COPYING file in the top-level
10  * directory.
11  */
12 
13 #include "qemu/osdep.h"
14 #include "qapi/error.h"
15 #include "hw/hotplug.h"
16 #include "hw/qdev-properties.h"
17 #include "hw/sysbus.h"
18 #include "qemu/bitops.h"
19 #include "qemu/module.h"
20 #include "hw/s390x/css.h"
21 #include "ccw-device.h"
22 #include "hw/s390x/css-bridge.h"
23 
24 /*
25  * Invoke device-specific unplug handler, disable the subchannel
26  * (including sending a channel report to the guest) and remove the
27  * device from the virtual css bus.
28  */
29 static void ccw_device_unplug(HotplugHandler *hotplug_dev,
30                               DeviceState *dev, Error **errp)
31 {
32     CcwDevice *ccw_dev = CCW_DEVICE(dev);
33     CCWDeviceClass *k = CCW_DEVICE_GET_CLASS(ccw_dev);
34     SubchDev *sch = ccw_dev->sch;
35     Error *err = NULL;
36 
37     if (k->unplug) {
38         k->unplug(hotplug_dev, dev, &err);
39         if (err) {
40             error_propagate(errp, err);
41             return;
42         }
43     }
44 
45     /*
46      * We should arrive here only for device_del, since we don't support
47      * direct hot(un)plug of channels.
48      */
49     assert(sch != NULL);
50     /* Subchannel is now disabled and no longer valid. */
51     sch->curr_status.pmcw.flags &= ~(PMCW_FLAGS_MASK_ENA |
52                                      PMCW_FLAGS_MASK_DNV);
53 
54     css_generate_sch_crws(sch->cssid, sch->ssid, sch->schid, 1, 0);
55 
56     qdev_unrealize(dev);
57 }
58 
59 static void virtual_css_bus_reset_hold(Object *obj, ResetType type)
60 {
61     /* This should actually be modelled via the generic css */
62     css_reset();
63 }
64 
65 static char *virtual_css_bus_get_dev_path(DeviceState *dev)
66 {
67     CcwDevice *ccw_dev = CCW_DEVICE(dev);
68     SubchDev *sch = ccw_dev->sch;
69 
70     return g_strdup_printf("/%02x.%1x.%04x", sch->cssid, sch->ssid, sch->devno);
71 }
72 
73 static void virtual_css_bus_class_init(ObjectClass *klass, void *data)
74 {
75     BusClass *k = BUS_CLASS(klass);
76     ResettableClass *rc = RESETTABLE_CLASS(klass);
77 
78     rc->phases.hold = virtual_css_bus_reset_hold;
79     k->get_dev_path = virtual_css_bus_get_dev_path;
80 }
81 
82 static const TypeInfo virtual_css_bus_info = {
83     .name = TYPE_VIRTUAL_CSS_BUS,
84     .parent = TYPE_BUS,
85     .instance_size = sizeof(VirtualCssBus),
86     .class_init = virtual_css_bus_class_init,
87 };
88 
89 VirtualCssBus *virtual_css_bus_init(void)
90 {
91     BusState *bus;
92     DeviceState *dev;
93 
94     /* Create bridge device */
95     dev = qdev_new(TYPE_VIRTUAL_CSS_BRIDGE);
96     object_property_add_child(qdev_get_machine(), TYPE_VIRTUAL_CSS_BRIDGE,
97                               OBJECT(dev));
98 
99     /* Create bus on bridge device */
100     bus = qbus_new(TYPE_VIRTUAL_CSS_BUS, dev, "virtual-css");
101 
102     /* Enable hotplugging */
103     qbus_set_hotplug_handler(bus, OBJECT(dev));
104 
105     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
106 
107     css_register_io_adapters(CSS_IO_ADAPTER_VIRTIO, true, false,
108                              0, &error_abort);
109 
110     return VIRTUAL_CSS_BUS(bus);
111  }
112 
113 /***************** Virtual-css Bus Bridge Device ********************/
114 
115 static bool prop_get_true(Object *obj, Error **errp)
116 {
117     return true;
118 }
119 
120 static void virtual_css_bridge_class_init(ObjectClass *klass, void *data)
121 {
122     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
123     DeviceClass *dc = DEVICE_CLASS(klass);
124 
125     hc->unplug = ccw_device_unplug;
126     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
127     object_class_property_add_bool(klass, "cssid-unrestricted",
128                                    prop_get_true, NULL);
129     object_class_property_set_description(klass, "cssid-unrestricted",
130             "A css device can use any cssid, regardless whether virtual"
131             " or not (read only, always true)");
132 }
133 
134 static const TypeInfo virtual_css_bridge_info = {
135     .name          = TYPE_VIRTUAL_CSS_BRIDGE,
136     .parent        = TYPE_SYS_BUS_DEVICE,
137     .instance_size = sizeof(VirtualCssBridge),
138     .class_init    = virtual_css_bridge_class_init,
139     .interfaces = (InterfaceInfo[]) {
140         { TYPE_HOTPLUG_HANDLER },
141         { }
142     }
143 };
144 
145 static void virtual_css_register(void)
146 {
147     type_register_static(&virtual_css_bridge_info);
148     type_register_static(&virtual_css_bus_info);
149 }
150 
151 type_init(virtual_css_register)
152