+typedef struct {
+ PCIDevice dev;
+ PCIBus *bus;
+} PCIBridge;
+
+void pci_bridge_write_config(PCIDevice *d,
+ uint32_t address, uint32_t val, int len)
+{
+ PCIBridge *s = (PCIBridge *)d;
+
+ if (address == 0x19 || (address == 0x18 && len > 1)) {
+ if (address == 0x19)
+ s->bus->bus_num = val & 0xff;
+ else
+ s->bus->bus_num = (val >> 8) & 0xff;
+#if defined(DEBUG_PCI)
+ printf ("pci-bridge: %s: Assigned bus %d\n", d->name, s->bus->bus_num);
+#endif
+ }
+ pci_default_write_config(d, address, val, len);
+}
+
+PCIBus *pci_bridge_init(PCIBus *bus, int devfn, uint32_t id,
+ pci_map_irq_fn map_irq, const char *name)
+{
+ PCIBridge *s;
+ s = (PCIBridge *)pci_register_device(bus, name, sizeof(PCIBridge),
+ devfn, NULL, pci_bridge_write_config);
+ s->dev.config[0x00] = id >> 16;
+ s->dev.config[0x01] = id >> 24;
+ s->dev.config[0x02] = id; // device_id
+ s->dev.config[0x03] = id >> 8;
+ s->dev.config[0x04] = 0x06; // command = bus master, pci mem
+ s->dev.config[0x05] = 0x00;
+ s->dev.config[0x06] = 0xa0; // status = fast back-to-back, 66MHz, no error
+ s->dev.config[0x07] = 0x00; // status = fast devsel
+ s->dev.config[0x08] = 0x00; // revision
+ s->dev.config[0x09] = 0x00; // programming i/f
+ s->dev.config[0x0A] = 0x04; // class_sub = PCI to PCI bridge
+ s->dev.config[0x0B] = 0x06; // class_base = PCI_bridge
+ s->dev.config[0x0D] = 0x10; // latency_timer
+ s->dev.config[0x0E] = 0x81; // header_type
+ s->dev.config[0x1E] = 0xa0; // secondary status
+
+ s->bus = pci_register_secondary_bus(&s->dev, map_irq);
+ return s->bus;
+}