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 "hw/pci/pci.h"
  14 #include "hw/pci/pci_bus.h"
  15 #include "hw/pci/pci_host.h"
  16 #include "hw/pci/pci_bus.h"
  17 #include "hw/pci/pci_bridge.h"
  18 #include "hw/i386/pc.h"
  19 #include "qemu/range.h"
  20 #include "qemu/error-report.h"
  21 #include "sysemu/numa.h"
  22
  23 #define TYPE_PXB_BUS "pxb-bus"
  24 #define PXB_BUS(obj) OBJECT_CHECK(PXBBus, (obj), TYPE_PXB_BUS)
  25
  26 typedef struct PXBBus {
  27     /*< private >*/
  28     PCIBus parent_obj;
  29     /*< public >*/
  30
  31     char bus_path[8];
  32 } PXBBus;
  33
  34 #define TYPE_PXB_DEVICE "pxb"
  35 #define PXB_DEV(obj) OBJECT_CHECK(PXBDev, (obj), TYPE_PXB_DEVICE)
  36
  37 typedef struct PXBDev {
  38     /*< private >*/
  39     PCIDevice parent_obj;
  40     /*< public >*/
  41
  42     uint8_t bus_nr;
  43     uint16_t numa_node;
  44 } PXBDev;
  45
  46 static GList *pxb_dev_list;
  47
  48 #define TYPE_PXB_HOST "pxb-host"
  49
  50 static int pxb_bus_num(PCIBus *bus)
  51 {
  52     PXBDev *pxb = PXB_DEV(bus->parent_dev);
  53
  54     return pxb->bus_nr;
  55 }
  56
  57 static bool pxb_is_root(PCIBus *bus)
  58 {
  59     return true; /* by definition */
  60 }
  61
  62 static uint16_t pxb_bus_numa_node(PCIBus *bus)
  63 {
  64     PXBDev *pxb = PXB_DEV(bus->parent_dev);
  65
  66     return pxb->numa_node;
  67 }
  68
  69 static void pxb_bus_class_init(ObjectClass *class, void *data)
  70 {
  71     PCIBusClass *pbc = PCI_BUS_CLASS(class);
  72
  73     pbc->bus_num = pxb_bus_num;
  74     pbc->is_root = pxb_is_root;
  75     pbc->numa_node = pxb_bus_numa_node;
  76 }
  77
  78 static const TypeInfo pxb_bus_info = {
  79     .name          = TYPE_PXB_BUS,
  80     .parent        = TYPE_PCI_BUS,
  81     .instance_size = sizeof(PXBBus),
  82     .class_init    = pxb_bus_class_init,
  83 };
  84
  85 static const char *pxb_host_root_bus_path(PCIHostState *host_bridge,
  86                                           PCIBus *rootbus)
  87 {
  88     PXBBus *bus = PXB_BUS(rootbus);
  89
  90     snprintf(bus->bus_path, 8, "0000:%02x", pxb_bus_num(rootbus));
  91     return bus->bus_path;
  92 }
  93
  94 static char *pxb_host_ofw_unit_address(const SysBusDevice *dev)
  95 {
  96     const PCIHostState *pxb_host;
  97     const PCIBus *pxb_bus;
  98     const PXBDev *pxb_dev;
  99     int position;
 100     const DeviceState *pxb_dev_base;
 101     const PCIHostState *main_host;
 102     const SysBusDevice *main_host_sbd;
 103
 104     pxb_host = PCI_HOST_BRIDGE(dev);
 105     pxb_bus = pxb_host->bus;
 106     pxb_dev = PXB_DEV(pxb_bus->parent_dev);
 107     position = g_list_index(pxb_dev_list, pxb_dev);
 108     assert(position >= 0);
 109
 110     pxb_dev_base = DEVICE(pxb_dev);
 111     main_host = PCI_HOST_BRIDGE(pxb_dev_base->parent_bus->parent);
 112     main_host_sbd = SYS_BUS_DEVICE(main_host);
 113
 114     if (main_host_sbd->num_mmio > 0) {
 115         return g_strdup_printf(TARGET_FMT_plx ",%x",
 116                                main_host_sbd->mmio[0].addr, position + 1);
 117     }
 118     if (main_host_sbd->num_pio > 0) {
 119         return g_strdup_printf("i%04x,%x",
 120                                main_host_sbd->pio[0], position + 1);
 121     }
 122     return NULL;
 123 }
 124
 125 static void pxb_host_class_init(ObjectClass *class, void *data)
 126 {
 127     DeviceClass *dc = DEVICE_CLASS(class);
 128     SysBusDeviceClass *sbc = SYS_BUS_DEVICE_CLASS(class);
 129     PCIHostBridgeClass *hc = PCI_HOST_BRIDGE_CLASS(class);
 130
 131     dc->fw_name = "pci";
 132     sbc->explicit_ofw_unit_address = pxb_host_ofw_unit_address;
 133     hc->root_bus_path = pxb_host_root_bus_path;
 134 }
 135
 136 static const TypeInfo pxb_host_info = {
 137     .name          = TYPE_PXB_HOST,
 138     .parent        = TYPE_PCI_HOST_BRIDGE,
 139     .class_init    = pxb_host_class_init,
 140 };
 141
 142 /*
 143  * Registers the PXB bus as a child of the i440fx root bus.
 144  *
 145  * Returns 0 on successs, -1 if i440fx host was not
 146  * found or the bus number is already in use.
 147  */
 148 static int pxb_register_bus(PCIDevice *dev, PCIBus *pxb_bus)
 149 {
 150     PCIBus *bus = dev->bus;
 151     int pxb_bus_num = pci_bus_num(pxb_bus);
 152
 153     if (bus->parent_dev) {
 154         error_report("PXB devices can be attached only to root bus.");
 155         return -1;
 156     }
 157
 158     QLIST_FOREACH(bus, &bus->child, sibling) {
 159         if (pci_bus_num(bus) == pxb_bus_num) {
 160             error_report("Bus %d is already in use.", pxb_bus_num);
 161             return -1;
 162         }
 163     }
 164     QLIST_INSERT_HEAD(&dev->bus->child, pxb_bus, sibling);
 165
 166     return 0;
 167 }
 168
 169 static int pxb_map_irq_fn(PCIDevice *pci_dev, int pin)
 170 {
 171     PCIDevice *pxb = pci_dev->bus->parent_dev;
 172
 173     /*
 174      * The bios does not index the pxb slot number when
 175      * it computes the IRQ because it resides on bus 0
 176      * and not on the current bus.
 177      * However QEMU routes the irq through bus 0 and adds
 178      * the pxb slot to the IRQ computation of the PXB
 179      * device.
 180      *
 181      * Synchronize between bios and QEMU by canceling
 182      * pxb's effect.
 183      */
 184     return pin - PCI_SLOT(pxb->devfn);
 185 }
 186
 187 static gint pxb_compare(gconstpointer a, gconstpointer b)
 188 {
 189     const PXBDev *pxb_a = a, *pxb_b = b;
 190
 191     return pxb_a->bus_nr < pxb_b->bus_nr ? -1 :
 192            pxb_a->bus_nr > pxb_b->bus_nr ?  1 :
 193            0;
 194 }
 195
 196 static int pxb_dev_initfn(PCIDevice *dev)
 197 {
 198     PXBDev *pxb = PXB_DEV(dev);
 199     DeviceState *ds, *bds;
 200     PCIBus *bus;
 201     const char *dev_name = NULL;
 202
 203     if (pxb->numa_node != NUMA_NODE_UNASSIGNED &&
 204         pxb->numa_node >= nb_numa_nodes) {
 205         error_report("Illegal numa node %d.", pxb->numa_node);
 206         return -EINVAL;
 207     }
 208
 209     if (dev->qdev.id && *dev->qdev.id) {
 210         dev_name = dev->qdev.id;
 211     }
 212
 213     ds = qdev_create(NULL, TYPE_PXB_HOST);
 214     bus = pci_bus_new(ds, "pxb-internal", NULL, NULL, 0, TYPE_PXB_BUS);
 215
 216     bus->parent_dev = dev;
 217     bus->address_space_mem = dev->bus->address_space_mem;
 218     bus->address_space_io = dev->bus->address_space_io;
 219     bus->map_irq = pxb_map_irq_fn;
 220
 221     bds = qdev_create(BUS(bus), "pci-bridge");
 222     bds->id = dev_name;
 223     qdev_prop_set_uint8(bds, PCI_BRIDGE_DEV_PROP_CHASSIS_NR, pxb->bus_nr);
 224     qdev_prop_set_bit(bds, PCI_BRIDGE_DEV_PROP_SHPC, false);
 225
 226     PCI_HOST_BRIDGE(ds)->bus = bus;
 227
 228     if (pxb_register_bus(dev, bus)) {
 229         return -EINVAL;
 230     }
 231
 232     qdev_init_nofail(ds);
 233     qdev_init_nofail(bds);
 234
 235     pci_word_test_and_set_mask(dev->config + PCI_STATUS,
 236                                PCI_STATUS_66MHZ | PCI_STATUS_FAST_BACK);
 237     pci_config_set_class(dev->config, PCI_CLASS_BRIDGE_HOST);
 238
 239     pxb_dev_list = g_list_insert_sorted(pxb_dev_list, pxb, pxb_compare);
 240     return 0;
 241 }
 242
 243 static void pxb_dev_exitfn(PCIDevice *pci_dev)
 244 {
 245     PXBDev *pxb = PXB_DEV(pci_dev);
 246
 247     pxb_dev_list = g_list_remove(pxb_dev_list, pxb);
 248 }
 249
 250 static Property pxb_dev_properties[] = {
 251     /* Note: 0 is not a legal a PXB bus number. */
 252     DEFINE_PROP_UINT8("bus_nr", PXBDev, bus_nr, 0),
 253     DEFINE_PROP_UINT16("numa_node", PXBDev, numa_node, NUMA_NODE_UNASSIGNED),
 254     DEFINE_PROP_END_OF_LIST(),
 255 };
 256
 257 static void pxb_dev_class_init(ObjectClass *klass, void *data)
 258 {
 259     DeviceClass *dc = DEVICE_CLASS(klass);
 260     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
 261
 262     k->init = pxb_dev_initfn;
 263     k->exit = pxb_dev_exitfn;
 264     k->vendor_id = PCI_VENDOR_ID_REDHAT;
 265     k->device_id = PCI_DEVICE_ID_REDHAT_PXB;
 266     k->class_id = PCI_CLASS_BRIDGE_HOST;
 267
 268     dc->desc = "PCI Expander Bridge";
 269     dc->props = pxb_dev_properties;
 270 }
 271
 272 static const TypeInfo pxb_dev_info = {
 273     .name          = TYPE_PXB_DEVICE,
 274     .parent        = TYPE_PCI_DEVICE,
 275     .instance_size = sizeof(PXBDev),
 276     .class_init    = pxb_dev_class_init,
 277 };
 278
 279 static void pxb_register_types(void)
 280 {
 281     type_register_static(&pxb_bus_info);
 282     type_register_static(&pxb_host_info);
 283     type_register_static(&pxb_dev_info);
 284 }
 285
 286 type_init(pxb_register_types)