there is a status word analogous to the PSL on VAX, on the alpha, and
i think there is a bit there that indicates if youre running on the interrupt
stack. the VAX has such a bit. so you might make it MD, but it would be an
easy test then.

isildur

On Wed, 5 Sep 2001, Matthew Jacob wrote:

> 
> Oh- and the reason this all came up (because this has been working peachy for
> a while) is that I finally started to look at the tape driver issues I've
> promised to do for a while, and my 8200 connected to a Qlogic 1040 on a pc164
> immediately gives BUSY status as it recovers from a bus reset (instead of a
> plain old 'NOT READY (in process of becoming ready)' that modern drives would
> do).
> 
> This then triggered the scsipi code to do a periph freeze and a timed thaw
> which cauesd the isp drivers isprequest entry point to be re-entered from
> hardclock- which then also hit the point of running a mailbox command to set
> target parameters. Boom.
> 
> Note that if isprequest is re-entered for queueing while from isp's interrupt,
> the mark of "don't use tsleep" can be known. But the assumption that I could
> only be called from interrupt (clock or otherwise) if I knew about it was
> clearly bad. Grumble.
> 
> -matt
> 
> 
>