Re: Linux/AXP keyboard not responding (PATCH)

Systemkennung Linux (
Thu, 25 Jul 1996 21:30:08 +0200 (MET DST)

Hi all,

> After a day (and a night ;)) of playing around, we finally have an Alpha
> running Linux again (2.0.8). A Jensen...
> Anyway, when booted with a 1.3.90 kernel it complains about the keyboard
> (something like "initialize_kbd: reset kbd failed, not POR") but it works
> fine. A 2.0.8 kernel also complains but fails to initialize the keyboard
> completely.
> I patched drivers/char/keyboard.c not to just give up after an error; I
> don't think this breaks anything, it just gives some more errors than
> usual when there really isn't a keyboard connected. At least now I can
> use the console keyboard again.
> I don't know if this is a Jensen only thing, but the patch is here anyway
> for those interested:

Your patch looks broken to me. The initialization routine should return
with the interrupt flags in the same state as they were on entry.

I had the same problem also with some of the MIPS machines I ported Linux
too. As it looks the keyboard doesn't like when itwhen the processor
talks to it too soon after the reset. A delay of about 20 microseconds
seems to be enough to fix the problem. The MIPS boxes so far could
also live without the keyboard reset. Maybe someone can state why this
keyboard reset was added?

The effects of this keyboard problem are a bit bizzarre. Whenever the
keyboard reset fails the floppy controller initialization fails also.
This does never happen on 100MHz R4000 machines but on faster machines
the faster the more often.