Serial configs on sparc64

[Joerg Wunsch]

As Garance A Drosihn wrote:

> I should mention that this is on an ultra-10, running 6.x-current
> as of sometime late Friday night.  My kernel does have the DDB, KDB,
> and BREAK_TO_DEBUGGER options added.  It also turns off WITNESS, if
> that makes any difference.

BREAK_TO_DEBUGGER is a no-op on most (if not all) sparc64 serial
drivers.  Everyone appears to be settled on ALT_BREAK_TO_DEBUGGER
now (which makes the console line no longer clean for transferring
arbitrary binary contents).

I once committed a BREAK_TO_DEBUGGER patch to the sab driver.

> I should also mention that I do get the serial console I'm expecting
> if I unplug the keyboard on my Ultra-10, but on i386 I can get serial
> console behavior while the keyboard is still plugged in.  I just have
> to put the right magic characters in /boot.config .  That doesn't seem
> to work on my Ultra10.

Right.  IMHO, you can force it to use the serial console by setting
the input-device and output-device variables in OBP to ttya.  But then
you lose the openfirmware console (terminal) emulator on the graphics
device.  (Not sure whether you need it.)

-- 
J"org Wunsch                                           Unix support engineer
joerg_wunsch at interface-systems.de        http://www.interface-systems.de/~j/