xref: /openbmc/qemu/hw/pci-bridge/pci_bridge_dev.c (revision 438c78da)
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     /* additional resources to reserve */
51     PCIResReserve res_reserve;
52 };
53 typedef struct PCIBridgeDev PCIBridgeDev;
54 
55 static void pci_bridge_dev_realize(PCIDevice *dev, Error **errp)
56 {
57     PCIBridge *br = PCI_BRIDGE(dev);
58     PCIBridgeDev *bridge_dev = PCI_BRIDGE_DEV(dev);
59     int err;
60     Error *local_err = NULL;
61 
62     pci_bridge_initfn(dev, TYPE_PCI_BUS);
63 
64     if (bridge_dev->flags & (1 << PCI_BRIDGE_DEV_F_SHPC_REQ)) {
65         dev->config[PCI_INTERRUPT_PIN] = 0x1;
66         memory_region_init(&bridge_dev->bar, OBJECT(dev), "shpc-bar",
67                            shpc_bar_size(dev));
68         err = shpc_init(dev, &br->sec_bus, &bridge_dev->bar, 0, errp);
69         if (err) {
70             goto shpc_error;
71         }
72     } else {
73         /* MSI is not applicable without SHPC */
74         bridge_dev->msi = ON_OFF_AUTO_OFF;
75     }
76 
77     err = slotid_cap_init(dev, 0, bridge_dev->chassis_nr, 0, errp);
78     if (err) {
79         goto slotid_error;
80     }
81 
82     if (bridge_dev->msi != ON_OFF_AUTO_OFF) {
83         /* it means SHPC exists, because MSI is needed by SHPC */
84 
85         err = msi_init(dev, 0, 1, true, true, &local_err);
86         /* Any error other than -ENOTSUP(board's MSI support is broken)
87          * is a programming error */
88         assert(!err || err == -ENOTSUP);
89         if (err && bridge_dev->msi == ON_OFF_AUTO_ON) {
90             /* Can't satisfy user's explicit msi=on request, fail */
91             error_append_hint(&local_err, "You have to use msi=auto (default) "
92                     "or msi=off with this machine type.\n");
93             error_propagate(errp, local_err);
94             goto msi_error;
95         }
96         assert(!local_err || bridge_dev->msi == ON_OFF_AUTO_AUTO);
97         /* With msi=auto, we fall back to MSI off silently */
98         error_free(local_err);
99     }
100 
101     err = pci_bridge_qemu_reserve_cap_init(dev, 0,
102                                          bridge_dev->res_reserve, errp);
103     if (err) {
104         goto cap_error;
105     }
106 
107     if (shpc_present(dev)) {
108         /* TODO: spec recommends using 64 bit prefetcheable BAR.
109          * Check whether that works well. */
110         pci_register_bar(dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY |
111                          PCI_BASE_ADDRESS_MEM_TYPE_64, &bridge_dev->bar);
112     }
113     return;
114 
115 cap_error:
116     msi_uninit(dev);
117 msi_error:
118     slotid_cap_cleanup(dev);
119 slotid_error:
120     if (shpc_present(dev)) {
121         shpc_cleanup(dev, &bridge_dev->bar);
122     }
123 shpc_error:
124     pci_bridge_exitfn(dev);
125 }
126 
127 static void pci_bridge_dev_exitfn(PCIDevice *dev)
128 {
129     PCIBridgeDev *bridge_dev = PCI_BRIDGE_DEV(dev);
130 
131     pci_del_capability(dev, PCI_CAP_ID_VNDR, sizeof(PCIBridgeQemuCap));
132     if (msi_present(dev)) {
133         msi_uninit(dev);
134     }
135     slotid_cap_cleanup(dev);
136     if (shpc_present(dev)) {
137         shpc_cleanup(dev, &bridge_dev->bar);
138     }
139     pci_bridge_exitfn(dev);
140 }
141 
142 static void pci_bridge_dev_instance_finalize(Object *obj)
143 {
144     /* this function is idempotent and handles (PCIDevice.shpc == NULL) */
145     shpc_free(PCI_DEVICE(obj));
146 }
147 
148 static void pci_bridge_dev_write_config(PCIDevice *d,
149                                         uint32_t address, uint32_t val, int len)
150 {
151     pci_bridge_write_config(d, address, val, len);
152     if (msi_present(d)) {
153         msi_write_config(d, address, val, len);
154     }
155     if (shpc_present(d)) {
156         shpc_cap_write_config(d, address, val, len);
157     }
158 }
159 
160 static void qdev_pci_bridge_dev_reset(DeviceState *qdev)
161 {
162     PCIDevice *dev = PCI_DEVICE(qdev);
163 
164     pci_bridge_reset(qdev);
165     if (shpc_present(dev)) {
166         shpc_reset(dev);
167     }
168 }
169 
170 static Property pci_bridge_dev_properties[] = {
171                     /* Note: 0 is not a legal chassis number. */
172     DEFINE_PROP_UINT8(PCI_BRIDGE_DEV_PROP_CHASSIS_NR, PCIBridgeDev, chassis_nr,
173                       0),
174     DEFINE_PROP_ON_OFF_AUTO(PCI_BRIDGE_DEV_PROP_MSI, PCIBridgeDev, msi,
175                             ON_OFF_AUTO_AUTO),
176     DEFINE_PROP_BIT(PCI_BRIDGE_DEV_PROP_SHPC, PCIBridgeDev, flags,
177                     PCI_BRIDGE_DEV_F_SHPC_REQ, true),
178     DEFINE_PROP_UINT32("bus-reserve", PCIBridgeDev,
179                        res_reserve.bus, -1),
180     DEFINE_PROP_SIZE("io-reserve", PCIBridgeDev,
181                      res_reserve.io, -1),
182     DEFINE_PROP_SIZE("mem-reserve", PCIBridgeDev,
183                      res_reserve.mem_non_pref, -1),
184     DEFINE_PROP_SIZE("pref32-reserve", PCIBridgeDev,
185                      res_reserve.mem_pref_32, -1),
186     DEFINE_PROP_SIZE("pref64-reserve", PCIBridgeDev,
187                      res_reserve.mem_pref_64, -1),
188 
189     DEFINE_PROP_END_OF_LIST(),
190 };
191 
192 static bool pci_device_shpc_present(void *opaque, int version_id)
193 {
194     PCIDevice *dev = opaque;
195 
196     return shpc_present(dev);
197 }
198 
199 static const VMStateDescription pci_bridge_dev_vmstate = {
200     .name = "pci_bridge",
201     .priority = MIG_PRI_PCI_BUS,
202     .fields = (VMStateField[]) {
203         VMSTATE_PCI_DEVICE(parent_obj, PCIBridge),
204         SHPC_VMSTATE(shpc, PCIDevice, pci_device_shpc_present),
205         VMSTATE_END_OF_LIST()
206     }
207 };
208 
209 static void pci_bridge_dev_hotplug_cb(HotplugHandler *hotplug_dev,
210                                       DeviceState *dev, Error **errp)
211 {
212     PCIDevice *pci_hotplug_dev = PCI_DEVICE(hotplug_dev);
213 
214     if (!shpc_present(pci_hotplug_dev)) {
215         error_setg(errp, "standard hotplug controller has been disabled for "
216                    "this %s", TYPE_PCI_BRIDGE_DEV);
217         return;
218     }
219     shpc_device_hotplug_cb(hotplug_dev, dev, errp);
220 }
221 
222 static void pci_bridge_dev_hot_unplug_request_cb(HotplugHandler *hotplug_dev,
223                                                  DeviceState *dev,
224                                                  Error **errp)
225 {
226     PCIDevice *pci_hotplug_dev = PCI_DEVICE(hotplug_dev);
227 
228     if (!shpc_present(pci_hotplug_dev)) {
229         error_setg(errp, "standard hotplug controller has been disabled for "
230                    "this %s", TYPE_PCI_BRIDGE_DEV);
231         return;
232     }
233     shpc_device_hot_unplug_request_cb(hotplug_dev, dev, errp);
234 }
235 
236 static void pci_bridge_dev_class_init(ObjectClass *klass, void *data)
237 {
238     DeviceClass *dc = DEVICE_CLASS(klass);
239     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
240     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
241 
242     k->realize = pci_bridge_dev_realize;
243     k->exit = pci_bridge_dev_exitfn;
244     k->config_write = pci_bridge_dev_write_config;
245     k->vendor_id = PCI_VENDOR_ID_REDHAT;
246     k->device_id = PCI_DEVICE_ID_REDHAT_BRIDGE;
247     k->class_id = PCI_CLASS_BRIDGE_PCI;
248     k->is_bridge = 1,
249     dc->desc = "Standard PCI Bridge";
250     dc->reset = qdev_pci_bridge_dev_reset;
251     dc->props = pci_bridge_dev_properties;
252     dc->vmsd = &pci_bridge_dev_vmstate;
253     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
254     hc->plug = pci_bridge_dev_hotplug_cb;
255     hc->unplug_request = pci_bridge_dev_hot_unplug_request_cb;
256 }
257 
258 static const TypeInfo pci_bridge_dev_info = {
259     .name              = TYPE_PCI_BRIDGE_DEV,
260     .parent            = TYPE_PCI_BRIDGE,
261     .instance_size     = sizeof(PCIBridgeDev),
262     .class_init        = pci_bridge_dev_class_init,
263     .instance_finalize = pci_bridge_dev_instance_finalize,
264     .interfaces = (InterfaceInfo[]) {
265         { TYPE_HOTPLUG_HANDLER },
266         { INTERFACE_CONVENTIONAL_PCI_DEVICE },
267         { }
268     }
269 };
270 
271 /*
272  * Multiseat bridge.  Same as the standard pci bridge, only with a
273  * different pci id, so we can match it easily in the guest for
274  * automagic multiseat configuration.  See docs/multiseat.txt for more.
275  */
276 static void pci_bridge_dev_seat_class_init(ObjectClass *klass, void *data)
277 {
278     DeviceClass *dc = DEVICE_CLASS(klass);
279     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
280 
281     k->device_id = PCI_DEVICE_ID_REDHAT_BRIDGE_SEAT;
282     dc->desc = "Standard PCI Bridge (multiseat)";
283 }
284 
285 static const TypeInfo pci_bridge_dev_seat_info = {
286     .name              = TYPE_PCI_BRIDGE_SEAT_DEV,
287     .parent            = TYPE_PCI_BRIDGE_DEV,
288     .instance_size     = sizeof(PCIBridgeDev),
289     .class_init        = pci_bridge_dev_seat_class_init,
290 };
291 
292 static void pci_bridge_dev_register(void)
293 {
294     type_register_static(&pci_bridge_dev_info);
295     type_register_static(&pci_bridge_dev_seat_info);
296 }
297 
298 type_init(pci_bridge_dev_register);
299