From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: Issues with SIS 964 chipset on SATA Date: Thu, 17 Feb 2005 09:38:30 +0100 Message-ID: <20050217083825.GA8695@suse.de> References: <4214551C.8030109@pobox.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Received: from ns.virtualhost.dk ([195.184.98.160]:17559 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id S262273AbVBQIik (ORCPT ); Thu, 17 Feb 2005 03:38:40 -0500 Content-Disposition: inline In-Reply-To: <4214551C.8030109@pobox.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Jeff Garzik Cc: Gary Poppitz , linux-ide@vger.kernel.org On Thu, Feb 17 2005, Jeff Garzik wrote: > Gary Poppitz wrote: > >We tracked down a problem with the 964 chipset with a 0x180 ID code that > >may save someone on the list some time. > > > >The chip will only transfer multiples of 4 bytes. Anything else will > >cause it to hang. > > > After further research, this is popping up on a number of chips (and > worked around in several vendor drivers). > > It looks like I will need to do a workaround for all SATA ATAPI devices: > if the transfer is not a multiple of 4 bytes, pad it with an DMA 1-3 > byte DMA segment. Yeah we definitely need something like that. The optimal solution is to make sure that all requests are fed through the bounce logic like fs requests. -- Jens Axboe