SCSI scanner, sym/ncr driver, pt(4)

Matthias Andree matthias.andree at
Mon Jan 30 08:38:32 PST 2006

On Mon, 30 Jan 2006, Stefan Esser wrote:

> >  > > But I wonder if the ncr(4) driver offered any advantages.
> >  > 
> >  > It doesn't. There used to be a time when it worked with the old 810 and
> >  > sym(4) didn't, but this no longer holds.
> Hmmm, this is news to me. That would require the sym driver to contain
> both sets of SCRIPTS code, the one from the NCR driver and the one from
> the sym driver.

The man page sym(4) reads (as of 6-STABLE):

     "sym also uses LOAD/STORE SCRIPTS instructions for chips that
     support it.  Only the early 810, 815 and 825 NCR chips do not
     support LOAD/STORE.  Use of LOAD/STORE instead of MEMORY MOVE
     allows SCRIPTS to access IO registers internal to the chip (no
     external PCI cycles).  As a result, the driver guarantees that no
     PCI self-mastering will occur for chips that support LOAD/STORE."

Matthias Andree

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