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