> From: Mike Ferrara <mikef@rtfm.sr.hp.com>
> Subject: Re: Status of SCSI SYS_INST?
> To: oster@cs.usask.ca (Greg Oster)
> Date: Mon, 9 Dec 1996 14:09:12 -0800 (PST)
> 
> According to Greg Oster:
> > thorpej@nas.nasa.gov writes:
> > > On Mon, 9 Dec 1996 10:47:11 -0700 (MST) 
> > >  Terry Lambert <terry@lambert.org> wrote:
> > > 
> > >  > Is there any status on the SCSI SYS_INST?
> > > 
> > > First, lets clarify...
> > > 
> > > There is no such thing as the "SCSI SYS_INST".  SYS_INST is a single
> > > program with both SCSI and HP-IB disk drivers.  It uses the same
> > > SCSI disk driver as the boot program, SYS_UBOOT.
> > [snippage]
> > 
> > Apologies for not thinking of this sooner, but it just occured to me that the 
> > problems booting with SYS_INST may have been the same as I was experiencing 
> > in July of last year (1995).
> > 
> > Try compiling SYS_INST with "-DSLOWSCSI" (yes, I'm aware that some of you 
> > don't have your HP boxes booting yet, much less compiling.  See below.).  
> > That's what let me get some of our 340's running from SCSI disks...  That 
> > option apparently lets "slow drives" work with "fast machines" (for some 
> > defn's of "slow" and "fast").  
> 

Oh yeah, I remember SLOWSCSI!  I put that in (in the pre 4.4 or NetBSD days)
when we upgraded some 400t's to 425t's (i.e., put in a 68040).  We were having
problems booting on them.  We never had any problem booting on 340s.  I think
the whole standalone driver is just a little shaky.  FYI: here is the last
thing I fixed in it (stand/scsivar.h):
----------------------------

revision 1.2
date: 1992/08/12 06:45:29;  author: mike;  state: Exp;  lines: +1 -1
increase MESG_IN/OUT field to 7 bytes.  Most drives only return 1 bytes
but some (MO) return more.  If the MESG_IN phase code fails to read all
the pending bytes, it throws the controller out of sync leading to a
variety of odd behaviors:
        boot program failures on warm reboot (ixfer_start failures)
        read requests that silently do nothing (VJ's old printf in sd.c)
this may also be the cause of the occasional failures of the boot
program on 68040s though I haven't tested it yet.

----------------------------
I never did test it either.  But this fix is in NetBSD.

> I'm not sure about the rest of the guys here, but _my_ problem is not
> that SYS_INST won't boot, but that disklabel that comes in SYS_INST
> can't find any of my scsi disks.
> 

I think you are still talking about the same thing.  SYS_INST should boot ok
since it is loaded by the boot ROM.  It is the standalone program that was
loaded (and using the standalone BSD drivers) that is having problems.  That
is the sort of problem that SLOWSCSI addressed.

> BTW ... BSD4.4 from berkeley shipped with an hp300 dd that included the
> disklabel, etc. I got one of those to boot, but it fails in another wierd
> way. I'll be spending more time with that, though before I give a final
> determination.
> 
Let me know what is failing there.  I built that dd image.