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gerrit.openbmc.org / openbmc / obmc-console / f3153347bb53a7ba600242c5d00ec5863fd4b4e4
commitf3153347bb53a7ba600242c5d00ec5863fd4b4e4[log] [tgz]
authorJeremy Kerr <jk@codeconstruct.com.au>Wed Sep 10 11:40:02 2025 +0800
committerEddie James <eajames@linux.ibm.com>Thu Sep 11 09:28:41 2025 -0500
tree505bbe118a8632dc048b243fe18a0c93987e51b3
parent860a8f8e6d0daf1e51ff783a18743007ad6d8031 [diff]
console-server: separate search for vuart node from tty setup

Move the code that sets up the tty to before the search for uart type.

Change-Id: Id08bfddd4e7710ba32f41aa10f4ce684b516a232
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
1 file changed
tree: 505bbe118a8632dc048b243fe18a0c93987e51b3
  1. conf/
  2. docs/
  3. subprojects/
  4. test/
  5. .clang-format
  6. .clang-tidy
  7. .gitignore
  8. .travis.yml
  9. CHANGELOG.md
  10. config-internal.h
  11. config.c
  12. config.h
  13. console-client.c
  14. console-dbus.c
  15. console-mux.c
  16. console-mux.h
  17. console-server.c
  18. console-server.h
  19. console-socket.c
  20. LICENSE
  21. log-handler.c
  22. meson.build
  23. meson.options
  24. OWNERS
  25. README.md
  26. ringbuffer.c
  27. socket-handler.c
  28. tty-handler.c
  29. util.c
  30. util.h
README.md

obmc-console

To Build

To build this project, run the following shell commands:

meson setup build
meson compile -C build

To test:

dbus-run-session meson test -C build

To Run Server

Running the server requires a serial port (e.g. /dev/ttyS0):

touch obmc-console.conf
./obmc-console-server --config obmc-console.conf ttyS0

To Connect Client

To connect to the server, simply run the client:

./obmc-console-client

To disconnect the client, use the standard ~. combination.

Underlying design

This shows how the host UART connection is abstracted within the BMC as a Unix domain socket.

            +---------------------------------------------------------------------------------------------+
            |                                                                                             |
            |       obmc-console-client       unix domain socket         obmc-console-server              |
            |                                                                                             |
            |     +----------------------+                           +------------------------+           |
            |     |   client.2200.conf   |  +---------------------+  | server.ttyVUART0.conf  |           |
        +---+--+  +----------------------+  |                     |  +------------------------+  +--------+-------+
Network    | 2200 +-->                      +->+ @obmc-console.host0 +<-+                        <--+ /dev/ttyVUART0 |   UARTs
        +---+--+  | console-id = "host0" |  |                     |  |  console-id = "host0"  |  +--------+-------+
            |     |                      |  +---------------------+  |                        |           |
            |     +----------------------+                           +------------------------+           |
            |                                                                                             |
            |                                                                                             |
            |                                                                                             |
            +---------------------------------------------------------------------------------------------+

This supports multiple independent consoles. The console-id is a unique portion for the unix domain socket created by the obmc-console-server instance. The server needs to know this because it needs to know what to name the pipe; the client needs to know it as it needs to form the abstract socket name to which to connect.

Mux Support

In some hardware designs, multiple UARTS may be available behind a Mux. Please reference docs/mux-support.md in that case.

Sample Development Setup

For developing obmc-console, we can use pseudo terminals (pty's) in Linux.

The socat command will output names of 2 pty's, one of which is the master and the other one is the slave. The master pty can be used to emulate a UART.

$ socat -d -d pty,raw,echo=0,link=pty1 pty,raw,echo=0,link=pty2

$ obmc-console-server --console-id dev $(realpath pty2)

$ obmc-console-client -i dev

# this message should appear for the client
$ echo "hi" > pty1