xref: /openbmc/qemu/hw/pci-bridge/pci_bridge_dev.c (revision 06329cce)
1 /*
2  * Standard PCI Bridge Device
3  *
4  * Copyright (c) 2011 Red Hat Inc. Author: Michael S. Tsirkin <mst@redhat.com>
5  *
6  * http://www.pcisig.com/specifications/conventional/pci_to_pci_bridge_architecture/
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License along
19  * with this program; if not, see <http://www.gnu.org/licenses/>.
20  */
21 
22 #include "qemu/osdep.h"
23 #include "qapi/error.h"
24 #include "hw/pci/pci_bridge.h"
25 #include "hw/pci/pci_ids.h"
26 #include "hw/pci/msi.h"
27 #include "hw/pci/shpc.h"
28 #include "hw/pci/slotid_cap.h"
29 #include "exec/memory.h"
30 #include "hw/pci/pci_bus.h"
31 #include "hw/hotplug.h"
32 
33 #define TYPE_PCI_BRIDGE_DEV      "pci-bridge"
34 #define TYPE_PCI_BRIDGE_SEAT_DEV "pci-bridge-seat"
35 #define PCI_BRIDGE_DEV(obj) \
36     OBJECT_CHECK(PCIBridgeDev, (obj), TYPE_PCI_BRIDGE_DEV)
37 
38 struct PCIBridgeDev {
39     /*< private >*/
40     PCIBridge parent_obj;
41     /*< public >*/
42 
43     MemoryRegion bar;
44     uint8_t chassis_nr;
45 #define PCI_BRIDGE_DEV_F_SHPC_REQ 0
46     uint32_t flags;
47 
48     OnOffAuto msi;
49 };
50 typedef struct PCIBridgeDev PCIBridgeDev;
51 
52 static void pci_bridge_dev_realize(PCIDevice *dev, Error **errp)
53 {
54     PCIBridge *br = PCI_BRIDGE(dev);
55     PCIBridgeDev *bridge_dev = PCI_BRIDGE_DEV(dev);
56     int err;
57     Error *local_err = NULL;
58 
59     pci_bridge_initfn(dev, TYPE_PCI_BUS);
60 
61     if (bridge_dev->flags & (1 << PCI_BRIDGE_DEV_F_SHPC_REQ)) {
62         dev->config[PCI_INTERRUPT_PIN] = 0x1;
63         memory_region_init(&bridge_dev->bar, OBJECT(dev), "shpc-bar",
64                            shpc_bar_size(dev));
65         err = shpc_init(dev, &br->sec_bus, &bridge_dev->bar, 0, errp);
66         if (err) {
67             goto shpc_error;
68         }
69     } else {
70         /* MSI is not applicable without SHPC */
71         bridge_dev->msi = ON_OFF_AUTO_OFF;
72     }
73 
74     err = slotid_cap_init(dev, 0, bridge_dev->chassis_nr, 0, errp);
75     if (err) {
76         goto slotid_error;
77     }
78 
79     if (bridge_dev->msi != ON_OFF_AUTO_OFF) {
80         /* it means SHPC exists, because MSI is needed by SHPC */
81 
82         err = msi_init(dev, 0, 1, true, true, &local_err);
83         /* Any error other than -ENOTSUP(board's MSI support is broken)
84          * is a programming error */
85         assert(!err || err == -ENOTSUP);
86         if (err && bridge_dev->msi == ON_OFF_AUTO_ON) {
87             /* Can't satisfy user's explicit msi=on request, fail */
88             error_append_hint(&local_err, "You have to use msi=auto (default) "
89                     "or msi=off with this machine type.\n");
90             error_propagate(errp, local_err);
91             goto msi_error;
92         }
93         assert(!local_err || bridge_dev->msi == ON_OFF_AUTO_AUTO);
94         /* With msi=auto, we fall back to MSI off silently */
95         error_free(local_err);
96     }
97 
98     if (shpc_present(dev)) {
99         /* TODO: spec recommends using 64 bit prefetcheable BAR.
100          * Check whether that works well. */
101         pci_register_bar(dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY |
102                          PCI_BASE_ADDRESS_MEM_TYPE_64, &bridge_dev->bar);
103     }
104     return;
105 
106 msi_error:
107     slotid_cap_cleanup(dev);
108 slotid_error:
109     if (shpc_present(dev)) {
110         shpc_cleanup(dev, &bridge_dev->bar);
111     }
112 shpc_error:
113     pci_bridge_exitfn(dev);
114 }
115 
116 static void pci_bridge_dev_exitfn(PCIDevice *dev)
117 {
118     PCIBridgeDev *bridge_dev = PCI_BRIDGE_DEV(dev);
119     if (msi_present(dev)) {
120         msi_uninit(dev);
121     }
122     slotid_cap_cleanup(dev);
123     if (shpc_present(dev)) {
124         shpc_cleanup(dev, &bridge_dev->bar);
125     }
126     pci_bridge_exitfn(dev);
127 }
128 
129 static void pci_bridge_dev_instance_finalize(Object *obj)
130 {
131     /* this function is idempotent and handles (PCIDevice.shpc == NULL) */
132     shpc_free(PCI_DEVICE(obj));
133 }
134 
135 static void pci_bridge_dev_write_config(PCIDevice *d,
136                                         uint32_t address, uint32_t val, int len)
137 {
138     pci_bridge_write_config(d, address, val, len);
139     if (msi_present(d)) {
140         msi_write_config(d, address, val, len);
141     }
142     if (shpc_present(d)) {
143         shpc_cap_write_config(d, address, val, len);
144     }
145 }
146 
147 static void qdev_pci_bridge_dev_reset(DeviceState *qdev)
148 {
149     PCIDevice *dev = PCI_DEVICE(qdev);
150 
151     pci_bridge_reset(qdev);
152     if (shpc_present(dev)) {
153         shpc_reset(dev);
154     }
155 }
156 
157 static Property pci_bridge_dev_properties[] = {
158                     /* Note: 0 is not a legal chassis number. */
159     DEFINE_PROP_UINT8(PCI_BRIDGE_DEV_PROP_CHASSIS_NR, PCIBridgeDev, chassis_nr,
160                       0),
161     DEFINE_PROP_ON_OFF_AUTO(PCI_BRIDGE_DEV_PROP_MSI, PCIBridgeDev, msi,
162                             ON_OFF_AUTO_AUTO),
163     DEFINE_PROP_BIT(PCI_BRIDGE_DEV_PROP_SHPC, PCIBridgeDev, flags,
164                     PCI_BRIDGE_DEV_F_SHPC_REQ, true),
165     DEFINE_PROP_END_OF_LIST(),
166 };
167 
168 static bool pci_device_shpc_present(void *opaque, int version_id)
169 {
170     PCIDevice *dev = opaque;
171 
172     return shpc_present(dev);
173 }
174 
175 static const VMStateDescription pci_bridge_dev_vmstate = {
176     .name = "pci_bridge",
177     .priority = MIG_PRI_PCI_BUS,
178     .fields = (VMStateField[]) {
179         VMSTATE_PCI_DEVICE(parent_obj, PCIBridge),
180         SHPC_VMSTATE(shpc, PCIDevice, pci_device_shpc_present),
181         VMSTATE_END_OF_LIST()
182     }
183 };
184 
185 static void pci_bridge_dev_hotplug_cb(HotplugHandler *hotplug_dev,
186                                       DeviceState *dev, Error **errp)
187 {
188     PCIDevice *pci_hotplug_dev = PCI_DEVICE(hotplug_dev);
189 
190     if (!shpc_present(pci_hotplug_dev)) {
191         error_setg(errp, "standard hotplug controller has been disabled for "
192                    "this %s", TYPE_PCI_BRIDGE_DEV);
193         return;
194     }
195     shpc_device_hotplug_cb(hotplug_dev, dev, errp);
196 }
197 
198 static void pci_bridge_dev_hot_unplug_request_cb(HotplugHandler *hotplug_dev,
199                                                  DeviceState *dev,
200                                                  Error **errp)
201 {
202     PCIDevice *pci_hotplug_dev = PCI_DEVICE(hotplug_dev);
203 
204     if (!shpc_present(pci_hotplug_dev)) {
205         error_setg(errp, "standard hotplug controller has been disabled for "
206                    "this %s", TYPE_PCI_BRIDGE_DEV);
207         return;
208     }
209     shpc_device_hot_unplug_request_cb(hotplug_dev, dev, errp);
210 }
211 
212 static void pci_bridge_dev_class_init(ObjectClass *klass, void *data)
213 {
214     DeviceClass *dc = DEVICE_CLASS(klass);
215     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
216     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
217 
218     k->realize = pci_bridge_dev_realize;
219     k->exit = pci_bridge_dev_exitfn;
220     k->config_write = pci_bridge_dev_write_config;
221     k->vendor_id = PCI_VENDOR_ID_REDHAT;
222     k->device_id = PCI_DEVICE_ID_REDHAT_BRIDGE;
223     k->class_id = PCI_CLASS_BRIDGE_PCI;
224     k->is_bridge = 1,
225     dc->desc = "Standard PCI Bridge";
226     dc->reset = qdev_pci_bridge_dev_reset;
227     dc->props = pci_bridge_dev_properties;
228     dc->vmsd = &pci_bridge_dev_vmstate;
229     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
230     hc->plug = pci_bridge_dev_hotplug_cb;
231     hc->unplug_request = pci_bridge_dev_hot_unplug_request_cb;
232 }
233 
234 static const TypeInfo pci_bridge_dev_info = {
235     .name              = TYPE_PCI_BRIDGE_DEV,
236     .parent            = TYPE_PCI_BRIDGE,
237     .instance_size     = sizeof(PCIBridgeDev),
238     .class_init        = pci_bridge_dev_class_init,
239     .instance_finalize = pci_bridge_dev_instance_finalize,
240     .interfaces = (InterfaceInfo[]) {
241         { TYPE_HOTPLUG_HANDLER },
242         { INTERFACE_CONVENTIONAL_PCI_DEVICE },
243         { }
244     }
245 };
246 
247 /*
248  * Multiseat bridge.  Same as the standard pci bridge, only with a
249  * different pci id, so we can match it easily in the guest for
250  * automagic multiseat configuration.  See docs/multiseat.txt for more.
251  */
252 static void pci_bridge_dev_seat_class_init(ObjectClass *klass, void *data)
253 {
254     DeviceClass *dc = DEVICE_CLASS(klass);
255     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
256 
257     k->device_id = PCI_DEVICE_ID_REDHAT_BRIDGE_SEAT;
258     dc->desc = "Standard PCI Bridge (multiseat)";
259 }
260 
261 static const TypeInfo pci_bridge_dev_seat_info = {
262     .name              = TYPE_PCI_BRIDGE_SEAT_DEV,
263     .parent            = TYPE_PCI_BRIDGE_DEV,
264     .instance_size     = sizeof(PCIBridgeDev),
265     .class_init        = pci_bridge_dev_seat_class_init,
266 };
267 
268 static void pci_bridge_dev_register(void)
269 {
270     type_register_static(&pci_bridge_dev_info);
271     type_register_static(&pci_bridge_dev_seat_info);
272 }
273 
274 type_init(pci_bridge_dev_register);
275