[coreboot] [PATCH][cbv2]Add serial port information to lbtable

Torsten Duwe duwe at lst.de
Thu Jan 17 12:55:56 CET 2008

On Wednesday 16 January 2008, Stefan Reinauer wrote:
> * Uwe Hermann <uwe at hermann-uwe.de> [080116 16:03]:
> > This doesn't look generic enough(?) Where does TTYS0_BASE come from?


> > I think not all of the boards define it, and even if they did,
> > TTYS0_BASE implies COM1, which is not always what you want.
> > We need a mechanism to allow other ports here (COM2, COM3, COM4).

This goes off into the wrong direction, IMO.

> > Yes, I think it's just a name, in theory you could assign any value
> > to TTYS0_BASE, but you get the point.
> yes, the variable should not be named TTYS0 but SERIAL_CONSOLE or
> something. But thats something I'd leave for v3.

Both not appropriate, strictly. There is only one serial port, for the console 
at best that everyone needs to care about until an OS is loaded.

The questions are:
1. of what type is the active console?
a) VGA-compatible
b) 8250-compatible
c) ...

2. where is it? This depends on 1.: VGA occupies a lot of unique ports,
8250 is specified sufficiently by a base address.

3. Is there additional information? A smarter payload might want to use e.g. 
the interrupt that we assigned to the port ;-)

Since the format is tagged, there should be no problem to reflect this.


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