From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mark Lord <mlord@pobox.com>
Subject: Re: [PATCH libata-dev-2.6 1/3] Add CHS support
Date: Sun, 06 Feb 2005 17:02:06 -0500
Message-ID: <420693DE.4030407@pobox.com>
References: <006d01c50c11$81003920$a801a8c0@tw.ibm.com> <4205B886.4070005@pobox.com> <42062CB7.2040701@pobox.com> <42063123.6070602@pobox.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Received: from orb.pobox.com ([207.8.226.5]:33488 "EHLO orb.pobox.com")
	by vger.kernel.org with ESMTP id S261178AbVBFWCQ (ORCPT
	<rfc822;linux-ide@vger.kernel.org>); Sun, 6 Feb 2005 17:02:16 -0500
In-Reply-To: <42063123.6070602@pobox.com>
Sender: linux-ide-owner@vger.kernel.org
List-Id: linux-ide@vger.kernel.org
To: Jeff Garzik <jgarzik@pobox.com>
Cc: Albert Lee <albertcc@tw.ibm.com>, Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>, Doug Maxey <dwm@maxeymade.com>, IDE Linux <linux-ide@vger.kernel.org>, "Mudama, Eric" <eric_mudama@Maxtor.com>

The exact sequence expected by certain pre-ATA4 (or earlier?) drives
was this:

SRST RESET
IDENTIFY
INITIALIZE DRIVE PARAMETERS
anything else..

Some drives were very specific about that exact sequence.

Nowadays, I don't bother with it for anything new I do,
as it is obsolete, and may even get rejected by modern drives.
But for the mainstream Linux ATA support, we should issue it
for drives which IDENTIFY themselves as conforming to pre-ATAx,
where the safest value for "x" is probably "4".

Cheers
-- 
Mark Lord
Real-Time Remedies Inc.
mlord@pobox.com

Jeff Garzik wrote:
> Mark Lord wrote:
> 
>> Jeff Garzik wrote:
>>
>>> 3) In Promise's GPL'd driver for their SATA (w/ PATA) cards, they 
>>> unconditionally execute the INITIALIZE DEVICE PARAMETERS command.  I 
>>> wonder if we should do the same.
>>
>>
>>
>> That command was *necessary* for certain drives at one time,
>> which refused all other commands until they received the IDP one.
> 
> 
> Except IDENTIFY DEVICE, presumably?
> 
> Thanks,
> 
>     Jeff
>