USB Serial Console?

Peter Grehan grehan at freebsd.org
Fri May 20 09:59:02 GMT 2005


>> In a similar vein, Firewire *can* be used as a console after it's 
>>probed, but there is the same issue with it not being supported by OFW.
> 
> 
> This isn't quite true..  Due to the implementation of console over
> firewire, it will work before it is probed...  This is due to the fact
> that console over firewire examines the memory directly (becaue firewire
> supports reading/writing memory w/o the host cpu's intervention), and
> doesn't need anything special to be initalized...

  Well... only if the OHCI i/f has been enabled and is allowing physical 
access. If it hasn't, it would be a bit of a task to do this in the loader.

> Recently, loader was improved to support dcons, and support hand off
> of the buffer from loader to kernel...  I haven't tried this new and
> improved loader, but it's suppose to work...

  Has that been committed to the loader ? I couldn't find any reference 
to dcons in the sys/boot dir, though there is conditional _BOOT code in 
sys/dcons and I can see the loader->kernel buf handoff code in dcons_os.c

later,

Peter.


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