SOL,obmc-console-client can't connect to the host OS

Jeremy Kerr jk at
Sun Nov 25 21:42:12 AEDT 2018

Hi Xiuzhi,

>  >What hardware platform is this?
> My platform is AMD X86 platform.

OK, so some of my assumptions about how things are hooked up may not be 
correct then. But just to check:

You mention that you're connecting to the host through a physical UART 
connection (UART4: GPIOF5-GPIOF7). Does this mean that you have a
separate SuperIO chip doing UART on the host side? (and you have *not*
connected to the AST2500's LPC bus?) 

If this is the case, you will not be using the VUART - we use that on 
our machines where the host is mastering the AST2500's LPC slave - and
so this means that the 0x3f8 port on host LPC is directly interfacing to
the AST2500's VUART, not a separate SuperIO chip with a UART.

This also means that you'll need to change the `cat /dev/ttyVUART0` 
tests to use the proper UART on the BMC side (because you're not using 
the VUART device).

I think the main issue is that you seem to be mixing up the Linux device
names (ttySx, which are zero-based in the default setup) with the
hardware device names (UARTn, which are one-based). Try referring to the
MMIO base addresses (0x1e78x000) to check that you're using the right
uart. I suspect that you want to be using ttyS3 if you're using UART4
from the datasheet.

Since you're using a physical UART too, you'll need to ensure that the
baud rates are the same on host and BMC.

Also, I would suggest not using any of the obmc-console stuff until 
ve confirmed that you can transfer data just using the serial 
devices on
host and BMC directly with `cat`.

> Which serial parameter should I use in the BMC file 
> etc/obmc-console.conf, BMC uart4 port or Host uart0?

Ah, that's a different setting.

The serial device that you specify on the obmc-console-server command
line is the UART that is connected to the host. This command-line
argument is configured through obmc-console at .service.

The serial device specified in the `local-tty` setting of obmc-
console.conf is a separate device that is typically connected to a BMC-
controlled port on the rear panel of the machine. This configures obmc-
console-server to mirror the serial data (from the host) to that port.

So, I'd suggest removing the `local-tty` setting when you start using
obmc-console, to avoid confusion. You can add it back (specifying a
serial port that is connected to only the BMC) when you want to mirror
to that port.



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