xref: /openbmc/qemu/docs/specs/pci-serial.rst (revision c5c0fdbe) 
1=======================
2QEMU PCI serial devices
3=======================
4
5QEMU implements some PCI serial devices which are simple PCI
6wrappers around one or more 16550 UARTs.
7
8There is one single-port variant and two multiport-variants.  Linux
9guests work out-of-the box with all cards.  There is a Windows inf file
10(``docs/qemupciserial.inf``) to set up the cards in Windows guests.
11
12
13Single-port card
14----------------
15
16Name:
17  ``pci-serial``
18PCI ID:
19  1b36:0002
20PCI Region 0:
21   IO bar, 8 bytes long, with the 16550 UART mapped to it.
22Interrupt:
23   Wired to pin A.
24
25
26Multiport cards
27---------------
28
29Name:
30  ``pci-serial-2x``, ``pci-serial-4x``
31PCI ID:
32  1b36:0003 (``-2x``) and 1b36:0004 (``-4x``)
33PCI Region 0:
34   IO bar, with two or four 16550 UARTs mapped after each other.
35   The first is at offset 0, the second at offset 8, and so on.
36Interrupt:
37   Wired to pin A.
38