1 /*
2  * PCI Expander Bridge Device Emulation
3  *
4  * Copyright (C) 2015 Red Hat Inc
5  *
6  * Authors:
7  *   Marcel Apfelbaum <marcel@redhat.com>
8  *
9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
10  * See the COPYING file in the top-level directory.
11  */
12 
13 #include "qemu/osdep.h"
14 #include "qapi/error.h"
15 #include "hw/pci/pci.h"
16 #include "hw/pci/pci_bus.h"
17 #include "hw/pci/pci_host.h"
18 #include "hw/qdev-properties.h"
19 #include "hw/pci/pci_bridge.h"
20 #include "qemu/range.h"
21 #include "qemu/error-report.h"
22 #include "qemu/module.h"
23 #include "sysemu/numa.h"
24 #include "hw/boards.h"
25 #include "qom/object.h"
26 
27 #define TYPE_PXB_BUS "pxb-bus"
28 typedef struct PXBBus PXBBus;
29 DECLARE_INSTANCE_CHECKER(PXBBus, PXB_BUS,
30                          TYPE_PXB_BUS)
31 
32 #define TYPE_PXB_PCIE_BUS "pxb-pcie-bus"
33 DECLARE_INSTANCE_CHECKER(PXBBus, PXB_PCIE_BUS,
34                          TYPE_PXB_PCIE_BUS)
35 
36 struct PXBBus {
37     /*< private >*/
38     PCIBus parent_obj;
39     /*< public >*/
40 
41     char bus_path[8];
42 };
43 
44 #define TYPE_PXB_DEVICE "pxb"
45 typedef struct PXBDev PXBDev;
46 DECLARE_INSTANCE_CHECKER(PXBDev, PXB_DEV,
47                          TYPE_PXB_DEVICE)
48 
49 #define TYPE_PXB_PCIE_DEVICE "pxb-pcie"
50 DECLARE_INSTANCE_CHECKER(PXBDev, PXB_PCIE_DEV,
51                          TYPE_PXB_PCIE_DEVICE)
52 
53 struct PXBDev {
54     /*< private >*/
55     PCIDevice parent_obj;
56     /*< public >*/
57 
58     uint8_t bus_nr;
59     uint16_t numa_node;
60     bool bypass_iommu;
61 };
62 
63 static PXBDev *convert_to_pxb(PCIDevice *dev)
64 {
65     return pci_bus_is_express(pci_get_bus(dev))
66         ? PXB_PCIE_DEV(dev) : PXB_DEV(dev);
67 }
68 
69 static GList *pxb_dev_list;
70 
71 #define TYPE_PXB_HOST "pxb-host"
72 
73 static int pxb_bus_num(PCIBus *bus)
74 {
75     PXBDev *pxb = convert_to_pxb(bus->parent_dev);
76 
77     return pxb->bus_nr;
78 }
79 
80 static uint16_t pxb_bus_numa_node(PCIBus *bus)
81 {
82     PXBDev *pxb = convert_to_pxb(bus->parent_dev);
83 
84     return pxb->numa_node;
85 }
86 
87 static void pxb_bus_class_init(ObjectClass *class, void *data)
88 {
89     PCIBusClass *pbc = PCI_BUS_CLASS(class);
90 
91     pbc->bus_num = pxb_bus_num;
92     pbc->numa_node = pxb_bus_numa_node;
93 }
94 
95 static const TypeInfo pxb_bus_info = {
96     .name          = TYPE_PXB_BUS,
97     .parent        = TYPE_PCI_BUS,
98     .instance_size = sizeof(PXBBus),
99     .class_init    = pxb_bus_class_init,
100 };
101 
102 static const TypeInfo pxb_pcie_bus_info = {
103     .name          = TYPE_PXB_PCIE_BUS,
104     .parent        = TYPE_PCIE_BUS,
105     .instance_size = sizeof(PXBBus),
106     .class_init    = pxb_bus_class_init,
107 };
108 
109 static const char *pxb_host_root_bus_path(PCIHostState *host_bridge,
110                                           PCIBus *rootbus)
111 {
112     PXBBus *bus = pci_bus_is_express(rootbus) ?
113                   PXB_PCIE_BUS(rootbus) : PXB_BUS(rootbus);
114 
115     snprintf(bus->bus_path, 8, "0000:%02x", pxb_bus_num(rootbus));
116     return bus->bus_path;
117 }
118 
119 static char *pxb_host_ofw_unit_address(const SysBusDevice *dev)
120 {
121     const PCIHostState *pxb_host;
122     const PCIBus *pxb_bus;
123     const PXBDev *pxb_dev;
124     int position;
125     const DeviceState *pxb_dev_base;
126     const PCIHostState *main_host;
127     const SysBusDevice *main_host_sbd;
128 
129     pxb_host = PCI_HOST_BRIDGE(dev);
130     pxb_bus = pxb_host->bus;
131     pxb_dev = convert_to_pxb(pxb_bus->parent_dev);
132     position = g_list_index(pxb_dev_list, pxb_dev);
133     assert(position >= 0);
134 
135     pxb_dev_base = DEVICE(pxb_dev);
136     main_host = PCI_HOST_BRIDGE(pxb_dev_base->parent_bus->parent);
137     main_host_sbd = SYS_BUS_DEVICE(main_host);
138 
139     if (main_host_sbd->num_mmio > 0) {
140         return g_strdup_printf(TARGET_FMT_plx ",%x",
141                                main_host_sbd->mmio[0].addr, position + 1);
142     }
143     if (main_host_sbd->num_pio > 0) {
144         return g_strdup_printf("i%04x,%x",
145                                main_host_sbd->pio[0], position + 1);
146     }
147     return NULL;
148 }
149 
150 static void pxb_host_class_init(ObjectClass *class, void *data)
151 {
152     DeviceClass *dc = DEVICE_CLASS(class);
153     SysBusDeviceClass *sbc = SYS_BUS_DEVICE_CLASS(class);
154     PCIHostBridgeClass *hc = PCI_HOST_BRIDGE_CLASS(class);
155 
156     dc->fw_name = "pci";
157     /* Reason: Internal part of the pxb/pxb-pcie device, not usable by itself */
158     dc->user_creatable = false;
159     sbc->explicit_ofw_unit_address = pxb_host_ofw_unit_address;
160     hc->root_bus_path = pxb_host_root_bus_path;
161 }
162 
163 static const TypeInfo pxb_host_info = {
164     .name          = TYPE_PXB_HOST,
165     .parent        = TYPE_PCI_HOST_BRIDGE,
166     .class_init    = pxb_host_class_init,
167 };
168 
169 /*
170  * Registers the PXB bus as a child of pci host root bus.
171  */
172 static void pxb_register_bus(PCIDevice *dev, PCIBus *pxb_bus, Error **errp)
173 {
174     PCIBus *bus = pci_get_bus(dev);
175     int pxb_bus_num = pci_bus_num(pxb_bus);
176 
177     if (bus->parent_dev) {
178         error_setg(errp, "PXB devices can be attached only to root bus");
179         return;
180     }
181 
182     QLIST_FOREACH(bus, &bus->child, sibling) {
183         if (pci_bus_num(bus) == pxb_bus_num) {
184             error_setg(errp, "Bus %d is already in use", pxb_bus_num);
185             return;
186         }
187     }
188     QLIST_INSERT_HEAD(&pci_get_bus(dev)->child, pxb_bus, sibling);
189 }
190 
191 static int pxb_map_irq_fn(PCIDevice *pci_dev, int pin)
192 {
193     PCIDevice *pxb = pci_get_bus(pci_dev)->parent_dev;
194 
195     /*
196      * The bios does not index the pxb slot number when
197      * it computes the IRQ because it resides on bus 0
198      * and not on the current bus.
199      * However QEMU routes the irq through bus 0 and adds
200      * the pxb slot to the IRQ computation of the PXB
201      * device.
202      *
203      * Synchronize between bios and QEMU by canceling
204      * pxb's effect.
205      */
206     return pin - PCI_SLOT(pxb->devfn);
207 }
208 
209 static gint pxb_compare(gconstpointer a, gconstpointer b)
210 {
211     const PXBDev *pxb_a = a, *pxb_b = b;
212 
213     return pxb_a->bus_nr < pxb_b->bus_nr ? -1 :
214            pxb_a->bus_nr > pxb_b->bus_nr ?  1 :
215            0;
216 }
217 
218 static void pxb_dev_realize_common(PCIDevice *dev, bool pcie, Error **errp)
219 {
220     PXBDev *pxb = convert_to_pxb(dev);
221     DeviceState *ds, *bds = NULL;
222     PCIBus *bus;
223     const char *dev_name = NULL;
224     Error *local_err = NULL;
225     MachineState *ms = MACHINE(qdev_get_machine());
226 
227     if (ms->numa_state == NULL) {
228         error_setg(errp, "NUMA is not supported by this machine-type");
229         return;
230     }
231 
232     if (pxb->numa_node != NUMA_NODE_UNASSIGNED &&
233         pxb->numa_node >= ms->numa_state->num_nodes) {
234         error_setg(errp, "Illegal numa node %d", pxb->numa_node);
235         return;
236     }
237 
238     if (dev->qdev.id && *dev->qdev.id) {
239         dev_name = dev->qdev.id;
240     }
241 
242     ds = qdev_new(TYPE_PXB_HOST);
243     if (pcie) {
244         bus = pci_root_bus_new(ds, dev_name, NULL, NULL, 0, TYPE_PXB_PCIE_BUS);
245     } else {
246         bus = pci_root_bus_new(ds, "pxb-internal", NULL, NULL, 0, TYPE_PXB_BUS);
247         bds = qdev_new("pci-bridge");
248         bds->id = g_strdup(dev_name);
249         qdev_prop_set_uint8(bds, PCI_BRIDGE_DEV_PROP_CHASSIS_NR, pxb->bus_nr);
250         qdev_prop_set_bit(bds, PCI_BRIDGE_DEV_PROP_SHPC, false);
251     }
252 
253     bus->parent_dev = dev;
254     bus->address_space_mem = pci_get_bus(dev)->address_space_mem;
255     bus->address_space_io = pci_get_bus(dev)->address_space_io;
256     bus->map_irq = pxb_map_irq_fn;
257 
258     PCI_HOST_BRIDGE(ds)->bus = bus;
259     PCI_HOST_BRIDGE(ds)->bypass_iommu = pxb->bypass_iommu;
260 
261     pxb_register_bus(dev, bus, &local_err);
262     if (local_err) {
263         error_propagate(errp, local_err);
264         goto err_register_bus;
265     }
266 
267     sysbus_realize_and_unref(SYS_BUS_DEVICE(ds), &error_fatal);
268     if (bds) {
269         qdev_realize_and_unref(bds, &bus->qbus, &error_fatal);
270     }
271 
272     pci_word_test_and_set_mask(dev->config + PCI_STATUS,
273                                PCI_STATUS_66MHZ | PCI_STATUS_FAST_BACK);
274     pci_config_set_class(dev->config, PCI_CLASS_BRIDGE_HOST);
275 
276     pxb_dev_list = g_list_insert_sorted(pxb_dev_list, pxb, pxb_compare);
277     return;
278 
279 err_register_bus:
280     object_unref(OBJECT(bds));
281     object_unparent(OBJECT(bus));
282     object_unref(OBJECT(ds));
283 }
284 
285 static void pxb_dev_realize(PCIDevice *dev, Error **errp)
286 {
287     if (pci_bus_is_express(pci_get_bus(dev))) {
288         error_setg(errp, "pxb devices cannot reside on a PCIe bus");
289         return;
290     }
291 
292     pxb_dev_realize_common(dev, false, errp);
293 }
294 
295 static void pxb_dev_exitfn(PCIDevice *pci_dev)
296 {
297     PXBDev *pxb = convert_to_pxb(pci_dev);
298 
299     pxb_dev_list = g_list_remove(pxb_dev_list, pxb);
300 }
301 
302 static Property pxb_dev_properties[] = {
303     /* Note: 0 is not a legal PXB bus number. */
304     DEFINE_PROP_UINT8("bus_nr", PXBDev, bus_nr, 0),
305     DEFINE_PROP_UINT16("numa_node", PXBDev, numa_node, NUMA_NODE_UNASSIGNED),
306     DEFINE_PROP_BOOL("bypass_iommu", PXBDev, bypass_iommu, false),
307     DEFINE_PROP_END_OF_LIST(),
308 };
309 
310 static void pxb_dev_class_init(ObjectClass *klass, void *data)
311 {
312     DeviceClass *dc = DEVICE_CLASS(klass);
313     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
314 
315     k->realize = pxb_dev_realize;
316     k->exit = pxb_dev_exitfn;
317     k->vendor_id = PCI_VENDOR_ID_REDHAT;
318     k->device_id = PCI_DEVICE_ID_REDHAT_PXB;
319     k->class_id = PCI_CLASS_BRIDGE_HOST;
320 
321     dc->desc = "PCI Expander Bridge";
322     device_class_set_props(dc, pxb_dev_properties);
323     dc->hotpluggable = false;
324     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
325 }
326 
327 static const TypeInfo pxb_dev_info = {
328     .name          = TYPE_PXB_DEVICE,
329     .parent        = TYPE_PCI_DEVICE,
330     .instance_size = sizeof(PXBDev),
331     .class_init    = pxb_dev_class_init,
332     .interfaces = (InterfaceInfo[]) {
333         { INTERFACE_CONVENTIONAL_PCI_DEVICE },
334         { },
335     },
336 };
337 
338 static void pxb_pcie_dev_realize(PCIDevice *dev, Error **errp)
339 {
340     if (!pci_bus_is_express(pci_get_bus(dev))) {
341         error_setg(errp, "pxb-pcie devices cannot reside on a PCI bus");
342         return;
343     }
344 
345     pxb_dev_realize_common(dev, true, errp);
346 }
347 
348 static void pxb_pcie_dev_class_init(ObjectClass *klass, void *data)
349 {
350     DeviceClass *dc = DEVICE_CLASS(klass);
351     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
352 
353     k->realize = pxb_pcie_dev_realize;
354     k->exit = pxb_dev_exitfn;
355     k->vendor_id = PCI_VENDOR_ID_REDHAT;
356     k->device_id = PCI_DEVICE_ID_REDHAT_PXB_PCIE;
357     k->class_id = PCI_CLASS_BRIDGE_HOST;
358 
359     dc->desc = "PCI Express Expander Bridge";
360     device_class_set_props(dc, pxb_dev_properties);
361     dc->hotpluggable = false;
362     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
363 }
364 
365 static const TypeInfo pxb_pcie_dev_info = {
366     .name          = TYPE_PXB_PCIE_DEVICE,
367     .parent        = TYPE_PCI_DEVICE,
368     .instance_size = sizeof(PXBDev),
369     .class_init    = pxb_pcie_dev_class_init,
370     .interfaces = (InterfaceInfo[]) {
371         { INTERFACE_CONVENTIONAL_PCI_DEVICE },
372         { },
373     },
374 };
375 
376 static void pxb_register_types(void)
377 {
378     type_register_static(&pxb_bus_info);
379     type_register_static(&pxb_pcie_bus_info);
380     type_register_static(&pxb_host_info);
381     type_register_static(&pxb_dev_info);
382     type_register_static(&pxb_pcie_dev_info);
383 }
384 
385 type_init(pxb_register_types)
386