From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mark Lord <lkml@rtr.ca>
Subject: Re: SATA speed. Should be 150 or 133?
Date: Thu, 23 Jun 2005 23:08:59 -0400
Message-ID: <42BB794B.6080109@rtr.ca>
References: <Pine.LNX.4.62.0506240135340.29382@bizon.gios.gov.pl>
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To: Krzysztof Oledzki <olel@ans.pl>
Cc: Jeff Garzik <jgarzik@pobox.com>, linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org

True SATA drives ignore the "transfer speed",
as it really is meaningless and does not apply.

But most (all?) first-gen SATA drives are really
PATA drives with a SATA bridge built-in.
Some of those drives require that Linux set the
DMA transfer speed for them to work reliably.

Last I looked, the highest valid PATA transfer
speed was still "UDMA/133".  150 just plain
doesn't exist for PATA (and the whole concept
doesn't exist for SATA, so ..)

Cheers