Re: Address of second TMSCP controller

[Johnny Billquist <bqt%update.uu.se@localhost>]

On 2021-01-26 13:57, Mouse wrote:
> > In addition to a broken TK70, which is being recognised fine by
> > NetBSD as mt0, I want to use a 40/80GB DLT on a Dilog SQ703 SCSI
> > TMSCP adapter.
>
> > NetBSD doesn't recognise it on booting.=C2=A0 I don't see anything
> > about addressing in the hardware wiki, does anybody know the address
> > where NetBSD looks for a second controller?
>
> As far as I can tell, it doesn't.  The only TMSCP device I see is
>
> mtc*		at uba? csr 0174500	# Tape MSCP ctlr
>
> Since there's no other mtc in sight, I rather wonder why it's mtc*
> rather than mtc0 - perhaps for machines with multiple buses?
>
> I imagine you could add a second mtc line to your config at whatever
> address you put your Dilog card at.  ISTR that DEC had a bunch of rules
> for such addresses - the phrase "floating CSR space" comes to mind -
> but I don't think anything keeps you from putting it anywhere as long
> as (a) it doesn't overlap with any other device and (b) you tell the
> kernel where you put it (in your second mtc line).

All correct.
And for the record, the "official" address of a second TMSCP controller 
then actually depends on what other devices you have on your machine.
But, assuming you have nothing else that sits in the floating CSR space, 
the second TMSCP controller would then be expected to be at 0160404.

But, as Mouse says, you basically pick any address you want. As long as 
the configuration on the card matches that in your config, you're good.

  Johnny

--
Johnny Billquist                  || "I'm on a bus
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email: bqt%softjar.se@localhost             ||  Reading murder books
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