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Date:      Sun, 19 Mar 1995 12:55:05 -0500 (EST)
From:      Peter Dufault <dufault@hda.com>
To:        freebsd-hackers@freefall.cdrom.com
Subject:   Re: kern/248: scbus attach/probe printf inconsistency
Message-ID:  <199503191755.MAA00648@hda.com>
In-Reply-To: <199503191400.IAA24755@bonkers.taronga.com> from "Peter da Silva" at Mar 19, 95 08:00:28 am

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Peter da Silva writes:
> 
> > For scsi the only unreal value is sectors/track.  All other values are
> > as reported by the drive.
> 
> Since s/t can vary either the other two numbers are made up (and not real) or
> you have to make up a s/t value (and thus they're not useful).
> 
> The only useful information the SCSI drive reports is the total number of
> blocks (unless it's a very old drive like mine that tells the absolute truth
> in all three categories, but is dinosaurs are in the minority).

I agree.  Even my token dinosaur drive uses ZBR.  I haven't checked
my 20MB Seagate drive lately.

I'll remove the Cyl/Head/Sectors except during the verbose boot.
That will also let the disk probe fit on a single line, it will
soon look something like:

> (aha0:3:0): "FUJITSU M2654S-512 010P" is a type 0 fixed SCSI 2
> sd2(aha0:3:0): Direct-Access 1959MB with 4014054 512 byte sectors.

And with verboseboot it can look like:

> (aha0:3:0): "FUJITSU M2654S-512 010P" is a type 0 fixed SCSI 2
> sd2(aha0:3:0): Direct-Access 1959MB with 4014054 512 byte sectors
> sd2(aha0:3:0): with 2179 cylinders, 21 heads, and 87 sectors/track.

Not that it matters, but all the info (including sectors/track)
is usually from the drive, but the drive makes it up.

Peter

-- 
Peter Dufault               Real Time Machine Control and Simulation
HD Associates, Inc.         Voice: 508 433 6936
dufault@hda.com             Fax:   508 433 5267



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