Subject: Re: Migrating MI-SCSI-Code to pmax/PI-SCSI?
To: None <port-pmax@netbsd.org>
From: Toru Nishimura <nisimura@itc.aist-nara.ac.jp>
List: port-pmax
Date: 09/03/1999 19:33:16
>> any hints how to migrate MI-SCSI-Code to pmax/PI-SCSI (am I right with
>> that?) ? I'd still need a bad block scanner & remapper badly and would
>> port it myself, but any hints are greatly appreciated.
>
> My current understanding is that the asc driver works (or mostly
> works), but no work has been done on the sii driver.	Toru, Michael?

The issue this moment is, how to migrate current DC7061 sii SCSI driver
into MI SCSI framework.  Solutions would be;

	[1] full scratch MI sii from the bottom
	[2] raminate current sii driver w/ 'thunk-layer' for MI SCSI
	[3] seek a way to 'co-exist' two different SCSI buses; oldscsi
	    for DS3100 and MI SCSI for others.

I spent couple of hours to make a hack job for MI SCSI kernel and placed
the patch file at;

	ftp.aist-nara.ac.jp:~ftp/pub/personal/nisimura/newasc.tgz

This file can produce MI SCSI kernel with MI NCR 53C9x driver.	Detailed
instrucion and precompiled kernel image are included.

/// F O R E W A R N S ///

- this is a hack job for people who are willing to try a potentially
  dangeous product might destroy the contents of disk drives.  NOT
  recommended for people who are satisfied with current NetBSD/pmax stability.
- for either of 3max, 3min, maxine or 3max+ only, and will spoil DECstation
  3100 functionality.
- it's known NOT WORK for SCSI tape drive.
- only limited numbers of SCSI disks were tested in field.
- not a part of NetBSD/pmax distribution and unlikely to be included in 
  future release as it is.

Feedbacks, informative to find/fix bugs and to enhance/improve the
robustness and stability of this driver, are very welcome.

- test on as many SCSI devices as possible.
- asc_ioasic.c should be reimplemented using bus_dma(9) properly.
- slow irregular-sized SCSI transaction seems to flow off kernel.
- find/fix many incompleteness/bugs I'm unware of.

Tohru Nishimura
Nara Institute of Science and Technology