From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Moore, Eric" Subject: Re: ATA Pass-Through support Date: Wed, 1 Mar 2006 23:14:58 -0700 Message-ID: <001c01c63dc0$a2f70270$271015ac@ericmoore> References: Mime-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit Return-path: Received: from mail0.lsil.com ([147.145.40.20]:19650 "EHLO mail0.lsil.com") by vger.kernel.org with ESMTP id S1751400AbWCBGY6 (ORCPT ); Thu, 2 Mar 2006 01:24:58 -0500 Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Quat Le , dougg@torque.net Cc: linux-scsi@vger.kernel.org On Wednesday, March 01, 2006 4:51 PM, Quat Le wrote: > I cannot tell if the LSI SAS HBA driver uses libata or not. A week ago I > did send LSI tech support a question asking if the SCSI-to-ATA > Translation Layer is done in the HBA driver or in a different layer on > Linux. So far I have not gotten any response. That's a good idea to > try this on a SATA disk connected to a SATA HBA. I will try this. > No, the mptsas driver is not using libata, however we are using scsi_transport_sas. This is firmware assist implementation, meaning SCSI-to-ATA translation is done in firmware; via queue_command entry point, all commands to both SAS and SATA devices are sent via SCSI_IO passthru. Is the SG_IO ATA passthru encapsalating an ATA command inside a SCSI CDB? If so, I don't think the firmware folks have not implemented that yet. When that is completed, I expect no change in driver, as its simply passthru, and the firmware will handle the request. There is an alternative, you can send an IOCTL=MPT_COMMAND IOCTL using the mptctl driver with the function set to MPI_FUNCTION_SATA_PASSTHROUGH. > I thought support for those two opcodes went into libata > for lk 2.6.15 as well but haven't written discrete code > to test it. Does the lsi SAS HBA use libata on its STP > (or direct connect) path? Eyeballing the libata code, > those opcodes are used internally. I know that > "smartctl -a -d ata /dev/sda" works when /dev/sda is a > SATA disk using libata on a regular SATA HBA. At present I > do not have any hardware nearby to test it. If you can direct > connect a SATA disk to a SATA controller on your motherboard > (i.e. bypassing the SAS HBA) does that make any difference? > What is smartctl? Is that part of Doug's sg_tools, or something else. Eric Moore LSI Logic