hw/pci-bridge/pci_expander_bridge.c

   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/pci/pci_bus.h"
  19 #include "hw/pci/pci_bridge.h"
  20 #include "hw/i386/pc.h"
  21 #include "qemu/range.h"
  22 #include "qemu/error-report.h"
  23 #include "sysemu/numa.h"
  24
  25 #define TYPE_PXB_BUS "pxb-bus"
  26 #define PXB_BUS(obj) OBJECT_CHECK(PXBBus, (obj), TYPE_PXB_BUS)
  27
  28 #define TYPE_PXB_PCIE_BUS "pxb-pcie-bus"
  29 #define PXB_PCIE_BUS(obj) OBJECT_CHECK(PXBBus, (obj), TYPE_PXB_PCIE_BUS)
  30
  31 typedef struct PXBBus {
  32     /*< private >*/
  33     PCIBus parent_obj;
  34     /*< public >*/
  35
  36     char bus_path[8];
  37 } PXBBus;
  38
  39 #define TYPE_PXB_DEVICE "pxb"
  40 #define PXB_DEV(obj) OBJECT_CHECK(PXBDev, (obj), TYPE_PXB_DEVICE)
  41
  42 #define TYPE_PXB_PCIE_DEVICE "pxb-pcie"
  43 #define PXB_PCIE_DEV(obj) OBJECT_CHECK(PXBDev, (obj), TYPE_PXB_PCIE_DEVICE)
  44
  45 typedef struct PXBDev {
  46     /*< private >*/
  47     PCIDevice parent_obj;
  48     /*< public >*/
  49
  50     uint8_t bus_nr;
  51     uint16_t numa_node;
  52 } PXBDev;
  53
  54 static PXBDev *convert_to_pxb(PCIDevice *dev)
  55 {
  56     return pci_bus_is_express(dev->bus) ? PXB_PCIE_DEV(dev) : PXB_DEV(dev);
  57 }
  58
  59 static GList *pxb_dev_list;
  60
  61 #define TYPE_PXB_HOST "pxb-host"
  62
  63 static int pxb_bus_num(PCIBus *bus)
  64 {
  65     PXBDev *pxb = convert_to_pxb(bus->parent_dev);
  66
  67     return pxb->bus_nr;
  68 }
  69
  70 static bool pxb_is_root(PCIBus *bus)
  71 {
  72     return true; /* by definition */
  73 }
  74
  75 static uint16_t pxb_bus_numa_node(PCIBus *bus)
  76 {
  77     PXBDev *pxb = convert_to_pxb(bus->parent_dev);
  78
  79     return pxb->numa_node;
  80 }
  81
  82 static void pxb_bus_class_init(ObjectClass *class, void *data)
  83 {
  84     PCIBusClass *pbc = PCI_BUS_CLASS(class);
  85
  86     pbc->bus_num = pxb_bus_num;
  87     pbc->is_root = pxb_is_root;
  88     pbc->numa_node = pxb_bus_numa_node;
  89 }
  90
  91 static const TypeInfo pxb_bus_info = {
  92     .name          = TYPE_PXB_BUS,
  93     .parent        = TYPE_PCI_BUS,
  94     .instance_size = sizeof(PXBBus),
  95     .class_init    = pxb_bus_class_init,
  96 };
  97
  98 static const TypeInfo pxb_pcie_bus_info = {
  99     .name          = TYPE_PXB_PCIE_BUS,
 100     .parent        = TYPE_PCIE_BUS,
 101     .instance_size = sizeof(PXBBus),
 102     .class_init    = pxb_bus_class_init,
 103 };
 104
 105 static const char *pxb_host_root_bus_path(PCIHostState *host_bridge,
 106                                           PCIBus *rootbus)
 107 {
 108     PXBBus *bus = pci_bus_is_express(rootbus) ?
 109                   PXB_PCIE_BUS(rootbus) : PXB_BUS(rootbus);
 110
 111     snprintf(bus->bus_path, 8, "0000:%02x", pxb_bus_num(rootbus));
 112     return bus->bus_path;
 113 }
 114
 115 static char *pxb_host_ofw_unit_address(const SysBusDevice *dev)
 116 {
 117     const PCIHostState *pxb_host;
 118     const PCIBus *pxb_bus;
 119     const PXBDev *pxb_dev;
 120     int position;
 121     const DeviceState *pxb_dev_base;
 122     const PCIHostState *main_host;
 123     const SysBusDevice *main_host_sbd;
 124
 125     pxb_host = PCI_HOST_BRIDGE(dev);
 126     pxb_bus = pxb_host->bus;
 127     pxb_dev = convert_to_pxb(pxb_bus->parent_dev);
 128     position = g_list_index(pxb_dev_list, pxb_dev);
 129     assert(position >= 0);
 130
 131     pxb_dev_base = DEVICE(pxb_dev);
 132     main_host = PCI_HOST_BRIDGE(pxb_dev_base->parent_bus->parent);
 133     main_host_sbd = SYS_BUS_DEVICE(main_host);
 134
 135     if (main_host_sbd->num_mmio > 0) {
 136         return g_strdup_printf(TARGET_FMT_plx ",%x",
 137                                main_host_sbd->mmio[0].addr, position + 1);
 138     }
 139     if (main_host_sbd->num_pio > 0) {
 140         return g_strdup_printf("i%04x,%x",
 141                                main_host_sbd->pio[0], position + 1);
 142     }
 143     return NULL;
 144 }
 145
 146 static void pxb_host_class_init(ObjectClass *class, void *data)
 147 {
 148     DeviceClass *dc = DEVICE_CLASS(class);
 149     SysBusDeviceClass *sbc = SYS_BUS_DEVICE_CLASS(class);
 150     PCIHostBridgeClass *hc = PCI_HOST_BRIDGE_CLASS(class);
 151
 152     dc->fw_name = "pci";
 153     /* Reason: Internal part of the pxb/pxb-pcie device, not usable by itself */
 154     dc->cannot_instantiate_with_device_add_yet = true;
 155     sbc->explicit_ofw_unit_address = pxb_host_ofw_unit_address;
 156     hc->root_bus_path = pxb_host_root_bus_path;
 157 }
 158
 159 static const TypeInfo pxb_host_info = {
 160     .name          = TYPE_PXB_HOST,
 161     .parent        = TYPE_PCI_HOST_BRIDGE,
 162     .class_init    = pxb_host_class_init,
 163 };
 164
 165 /*
 166  * Registers the PXB bus as a child of pci host root bus.
 167  */
 168 static void pxb_register_bus(PCIDevice *dev, PCIBus *pxb_bus, Error **errp)
 169 {
 170     PCIBus *bus = dev->bus;
 171     int pxb_bus_num = pci_bus_num(pxb_bus);
 172
 173     if (bus->parent_dev) {
 174         error_setg(errp, "PXB devices can be attached only to root bus");
 175         return;
 176     }
 177
 178     QLIST_FOREACH(bus, &bus->child, sibling) {
 179         if (pci_bus_num(bus) == pxb_bus_num) {
 180             error_setg(errp, "Bus %d is already in use", pxb_bus_num);
 181             return;
 182         }
 183     }
 184     QLIST_INSERT_HEAD(&dev->bus->child, pxb_bus, sibling);
 185 }
 186
 187 static int pxb_map_irq_fn(PCIDevice *pci_dev, int pin)
 188 {
 189     PCIDevice *pxb = pci_dev->bus->parent_dev;
 190
 191     /*
 192      * The bios does not index the pxb slot number when
 193      * it computes the IRQ because it resides on bus 0
 194      * and not on the current bus.
 195      * However QEMU routes the irq through bus 0 and adds
 196      * the pxb slot to the IRQ computation of the PXB
 197      * device.
 198      *
 199      * Synchronize between bios and QEMU by canceling
 200      * pxb's effect.
 201      */
 202     return pin - PCI_SLOT(pxb->devfn);
 203 }
 204
 205 static gint pxb_compare(gconstpointer a, gconstpointer b)
 206 {
 207     const PXBDev *pxb_a = a, *pxb_b = b;
 208
 209     return pxb_a->bus_nr < pxb_b->bus_nr ? -1 :
 210            pxb_a->bus_nr > pxb_b->bus_nr ?  1 :
 211            0;
 212 }
 213
 214 static void pxb_dev_realize_common(PCIDevice *dev, bool pcie, Error **errp)
 215 {
 216     PXBDev *pxb = convert_to_pxb(dev);
 217     DeviceState *ds, *bds = NULL;
 218     PCIBus *bus;
 219     const char *dev_name = NULL;
 220     Error *local_err = NULL;
 221
 222     if (pxb->numa_node != NUMA_NODE_UNASSIGNED &&
 223         pxb->numa_node >= nb_numa_nodes) {
 224         error_setg(errp, "Illegal numa node %d", pxb->numa_node);
 225         return;
 226     }
 227
 228     if (dev->qdev.id && *dev->qdev.id) {
 229         dev_name = dev->qdev.id;
 230     }
 231
 232     ds = qdev_create(NULL, TYPE_PXB_HOST);
 233     if (pcie) {
 234         bus = pci_bus_new(ds, dev_name, NULL, NULL, 0, TYPE_PXB_PCIE_BUS);
 235     } else {
 236         bus = pci_bus_new(ds, "pxb-internal", NULL, NULL, 0, TYPE_PXB_BUS);
 237         bds = qdev_create(BUS(bus), "pci-bridge");
 238         bds->id = dev_name;
 239         qdev_prop_set_uint8(bds, PCI_BRIDGE_DEV_PROP_CHASSIS_NR, pxb->bus_nr);
 240         qdev_prop_set_bit(bds, PCI_BRIDGE_DEV_PROP_SHPC, false);
 241     }
 242
 243     bus->parent_dev = dev;
 244     bus->address_space_mem = dev->bus->address_space_mem;
 245     bus->address_space_io = dev->bus->address_space_io;
 246     bus->map_irq = pxb_map_irq_fn;
 247
 248     PCI_HOST_BRIDGE(ds)->bus = bus;
 249
 250     pxb_register_bus(dev, bus, &local_err);
 251     if (local_err) {
 252         error_propagate(errp, local_err);
 253         goto err_register_bus;
 254     }
 255
 256     qdev_init_nofail(ds);
 257     if (bds) {
 258         qdev_init_nofail(bds);
 259     }
 260
 261     pci_word_test_and_set_mask(dev->config + PCI_STATUS,
 262                                PCI_STATUS_66MHZ | PCI_STATUS_FAST_BACK);
 263     pci_config_set_class(dev->config, PCI_CLASS_BRIDGE_HOST);
 264
 265     pxb_dev_list = g_list_insert_sorted(pxb_dev_list, pxb, pxb_compare);
 266     return;
 267
 268 err_register_bus:
 269     object_unref(OBJECT(bds));
 270     object_unparent(OBJECT(bus));
 271     object_unref(OBJECT(ds));
 272 }
 273
 274 static void pxb_dev_realize(PCIDevice *dev, Error **errp)
 275 {
 276     if (pci_bus_is_express(dev->bus)) {
 277         error_setg(errp, "pxb devices cannot reside on a PCIe bus");
 278         return;
 279     }
 280
 281     pxb_dev_realize_common(dev, false, errp);
 282 }
 283
 284 static void pxb_dev_exitfn(PCIDevice *pci_dev)
 285 {
 286     PXBDev *pxb = convert_to_pxb(pci_dev);
 287
 288     pxb_dev_list = g_list_remove(pxb_dev_list, pxb);
 289 }
 290
 291 static Property pxb_dev_properties[] = {
 292     /* Note: 0 is not a legal PXB bus number. */
 293     DEFINE_PROP_UINT8("bus_nr", PXBDev, bus_nr, 0),
 294     DEFINE_PROP_UINT16("numa_node", PXBDev, numa_node, NUMA_NODE_UNASSIGNED),
 295     DEFINE_PROP_END_OF_LIST(),
 296 };
 297
 298 static void pxb_dev_class_init(ObjectClass *klass, void *data)
 299 {
 300     DeviceClass *dc = DEVICE_CLASS(klass);
 301     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
 302
 303     k->realize = pxb_dev_realize;
 304     k->exit = pxb_dev_exitfn;
 305     k->vendor_id = PCI_VENDOR_ID_REDHAT;
 306     k->device_id = PCI_DEVICE_ID_REDHAT_PXB;
 307     k->class_id = PCI_CLASS_BRIDGE_HOST;
 308
 309     dc->desc = "PCI Expander Bridge";
 310     dc->props = pxb_dev_properties;
 311     dc->hotpluggable = false;
 312     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
 313 }
 314
 315 static const TypeInfo pxb_dev_info = {
 316     .name          = TYPE_PXB_DEVICE,
 317     .parent        = TYPE_PCI_DEVICE,
 318     .instance_size = sizeof(PXBDev),
 319     .class_init    = pxb_dev_class_init,
 320 };
 321
 322 static void pxb_pcie_dev_realize(PCIDevice *dev, Error **errp)
 323 {
 324     if (!pci_bus_is_express(dev->bus)) {
 325         error_setg(errp, "pxb-pcie devices cannot reside on a PCI bus");
 326         return;
 327     }
 328
 329     pxb_dev_realize_common(dev, true, errp);
 330 }
 331
 332 static void pxb_pcie_dev_class_init(ObjectClass *klass, void *data)
 333 {
 334     DeviceClass *dc = DEVICE_CLASS(klass);
 335     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
 336
 337     k->realize = pxb_pcie_dev_realize;
 338     k->exit = pxb_dev_exitfn;
 339     k->vendor_id = PCI_VENDOR_ID_REDHAT;
 340     k->device_id = PCI_DEVICE_ID_REDHAT_PXB_PCIE;
 341     k->class_id = PCI_CLASS_BRIDGE_HOST;
 342
 343     dc->desc = "PCI Express Expander Bridge";
 344     dc->props = pxb_dev_properties;
 345     dc->hotpluggable = false;
 346     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
 347 }
 348
 349 static const TypeInfo pxb_pcie_dev_info = {
 350     .name          = TYPE_PXB_PCIE_DEVICE,
 351     .parent        = TYPE_PCI_DEVICE,
 352     .instance_size = sizeof(PXBDev),
 353     .class_init    = pxb_pcie_dev_class_init,
 354 };
 355
 356 static void pxb_register_types(void)
 357 {
 358     type_register_static(&pxb_bus_info);
 359     type_register_static(&pxb_pcie_bus_info);
 360     type_register_static(&pxb_host_info);
 361     type_register_static(&pxb_dev_info);
 362     type_register_static(&pxb_pcie_dev_info);
 363 }
 364
 365 type_init(pxb_register_types)