From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: [PATCH] libata: add enclosure management support Date: Fri, 18 Jan 2008 20:33:51 -0600 Message-ID: <1200710031.3111.101.camel@localhost.localdomain> References: <20080115164417.4a5e2789@appleyard> <1200610243.3255.47.camel@localhost.localdomain> <20080118085227.4b7a379f@appleyard> <1200676281.3111.20.camel@localhost.localdomain> <20080118094116.7ac94f2e@appleyard> <1200701795.3111.89.camel@localhost.localdomain> <20080118163512.65d93c53@appleyard> <1200703638.3111.95.camel@localhost.localdomain> <20080118165525.57749ac8@appleyard> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from accolon.hansenpartnership.com ([76.243.235.52]:39855 "EHLO accolon.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758264AbYASCd5 (ORCPT ); Fri, 18 Jan 2008 21:33:57 -0500 In-Reply-To: <20080118165525.57749ac8@appleyard> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: kristen.c.accardi@intel.com Cc: jeff@garzik.org, linux-ide@vger.kernel.org On Fri, 2008-01-18 at 16:55 -0800, Kristen Carlson Accardi wrote: > On Fri, 18 Jan 2008 18:47:18 -0600 > James Bottomley wrote: > > > On Fri, 2008-01-18 at 16:35 -0800, Kristen Carlson Accardi wrote: > > > > Unfortunately, all the dual SAS/SATA enclosures seem to be coming > > > > with either SGPIO devices or full fledged SES-2 devices. I've > > > > actually got both (a backplane with SGPIO and an internal > > > > SAS/SATA enclosure with SES-2). Unfortunately, I don't have the > > > > necessary information to drive the SGPIO one ... it's connected > > > > directly to an aix94xx using the mini4i SGPIO signals ... I think > > > > aic94xx can drive them, we just don't have the programming > > > > information. The other is a standard SES-2 device, which I think > > > > I might be able to get working. > > > > > > > > > > Having documentation would be pretty helpful :). I know for ICH8, > > > if you read the docs it says that it supports SGPIO as well. But > > > then you realize it supports SGPIO via the LED protocol, wired up > > > to translate LED to SGPIO via hardware. But, even if it did > > > support straight SGPIO, this design can accommodate that. Can we > > > see the documentation for the SES-2 device? > > > > Yes, sure; SES-2 is here (usual place, since it's a SCSI standard): > > > > http://www.t10.org/ftp/t10/drafts/ses2/ses2r19a.pdf > > > > SGPIO is more convoluted. The canonical link is > > http://www.sffcommittee.com/ but that just seems to send you back to > > seagate. The actual standard is this one: > > > > ftp://ftp.seagate.com/sff/SFF-8485.PDF > > > > James > > > > > > No, I meant for the actual device. The specs don't help all that much > in the area of actually transmitting the messages at the driver level - > at least they don't for AHCI. OK, now I'm confused. A SES-2 device is a SCSI device. The standard defines everything for them. They sit on the bus like any other SCSI device. SGPIO is a separate bus; it's also fully defined in SFF-8485, so my SFF-8485 compliant backplane should be fully defined by the spec as well. If you're asking how the SGPIO transciever in the aic94xx works, that's the piece I don't know ... it's not in the RAZOR spec. James