QEMU PCI serial devices
QEMU implements some PCI serial devices which are simple PCI wrappers around one or more 16550 UARTs.
There is one single-port variant and two multiport-variants.  Linux
guests work out-of-the box with all cards.  There is a Windows inf file
(docs/qemupciserial.inf) to set up the cards in Windows guests.
Single-port card
- Name:
- pci-serial
- PCI ID:
- 1b36:0002 
- PCI Region 0:
- IO bar, 8 bytes long, with the 16550 UART mapped to it. 
- Interrupt:
- Wired to pin A. 
Multiport cards
- Name:
- pci-serial-2x,- pci-serial-4x
- PCI ID:
- 1b36:0003 ( - -2x) and 1b36:0004 (- -4x)
- PCI Region 0:
- IO bar, with two or four 16550 UARTs mapped after each other. The first is at offset 0, the second at offset 8, and so on. 
- Interrupt:
- Wired to pin A.