qemu/docs/pcie_pci_bridge.txt

1 Generic PCI Express to PCI Bridge
6 PCIE-to-PCI bridge is a new method for legacy PCI
9 Previously Intel DMI-to-PCI bridge was used for this purpose.
12 PCIE-to-PCI bridge should now be used for any legacy PCI device usage
15 This generic PCIE-PCI bridge is a cross-platform device,
17 see 'PCIE-PCI bridge hot-plug' section),
18 and supports devices hot-plug into the bridge itself
21 Hot-plug of legacy PCI devices into the bridge
22 is provided by bridge's built-in Standard hot-plug Controller.
25 PCIE-PCI bridge hot-plug
27 Guest OSes require extra efforts to enable PCIE-PCI bridge hot-plug.
36 that is planned to have PCIE-PCI bridge hot-plugged in.
76 -device pcie-pci-bridge,id=br1,bus=rp1 \
77 -device pcie-pci-bridge,id=br2,bus=rp2 \
81 device_add pcie-pci-bridge,id=br3,bus=rp3 \
90     - e1000 plugged into the first bridge.
92     - PCIE-PCI bridge, plugged into QEMU generic root port;
93     - 2 e1000 cards, one plugged into the cold-plugged PCIE-PCI bridge,
94                      another plugged into the hot-plugged bridge.
98 The PCIE-PCI bridge can be hot-plugged only into pcie-root-port that
100 hot-plugged bridge.
102 Windows 7 and older versions don't support hot-plug devices into the PCIE-PCI bridge.
103 To enable device hot-plug into the bridge on Linux there're 3 ways:
106 3) Set 'msi' property to off - this forces the bridge to use legacy INTx,
107     which allows the bridge to notify the OS about hot-plug event without having
112 The PCIE-PCI bridge is based on PCI-PCI bridge, but also accumulates PCI Express