From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: hdregs.h puts csfo at word 129 - wrong, that's vendor specific Date: Thu, 24 Mar 2005 22:03:20 -0500 Message-ID: <42437F78.8090703@pobox.com> References: <4243693F.9090008@yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Received: from parcelfarce.linux.theplanet.co.uk ([195.92.249.252]:9370 "EHLO parcelfarce.linux.theplanet.co.uk") by vger.kernel.org with ESMTP id S261356AbVCYDDd (ORCPT ); Thu, 24 Mar 2005 22:03:33 -0500 In-Reply-To: <4243693F.9090008@yahoo.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Chris Hann Cc: linux-ide list Chris Hann wrote: > ide-disk.c checks csfo bit 0 to see if the cache is available on a device > hdregs.h maps csfo to word 129 of the Identify Device information > the latest ATA documentation, e00159r3 Mandatory IDENTIFY DEVICE > information, says words 129-159 are Vendor specific. > > Why is the driver switching on cache operations based on a word that has > nothing to do with cache? Good question... I would guess that it's some pre-ATA4 legacy magic, but that's just a guess. Jeff