On Fri, 04 Jul 1997 10:10:21 -0800,
brian wildasinn <bwildasi@csulb.edu> wrote:
> 
> Colin Wood's FAQ for mac68k mentions a patch for the sbc kernels which
> i've been told doesn't apply to a Q700 since that machine uses an esp
> driver. Jonathan's suggestion seems to have the genericsbc patch for
> older macs in mind.

NetBSD's SCSI disk driver actually consists of three layers; fixed
direct access device layer, generic SCSI layer, and SCSI controller
layer.  The first two layers are always used no matter which
controller layer you use (with possibly one exception of asc driver).

> [Jonathan O'Brien's suggestion] 
> > The problem you're seeing is similar to something I experienced
> > about a year ago. Some scsi drives don't handle residual data
> > pointers correctly (I don't fully understand the problem, just
> > know of a potential fix). On my drive, I would create a file
> > on the drive and the partition would no longer be accessable like
> > you describe. The solution was to add an entry into the quirk
> > table to force the "SDEV_AUTOSAVE" then build a new kernel with
> > the change.
> > 
> > Here's an example entry in src/sys/scsi/scsiconf.c:
> > 
> >         {{T_DIRECT, T_FIXED,
> >          "DEC     ", "RZ55     (C) DEC", ""},     SDEV_AUTOSAVE},

This src/sys/scsi/scsiconf.c is a file consisting the middle layer,
so it may apply to esp driver as well as ncr or sbc driver.

> >         sbc0 at obio? flags 0x5

This is about the last layer, and therefore does apply only to sbc
driver, but not ncr or esp driver.

Ken