From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mikael Pettersson Subject: Re: [RFC][PATCH] ahci: Add support for Promise PDC42819 Date: Tue, 2 Sep 2008 14:08:02 +0200 Message-ID: <18621.11426.870514.781750@harpo.it.uu.se> References: <65a6ef750809020403i52228319u9e3197e4062941bc@mail.gmail.com> <48BD2136.1020101@garzik.org> <65a6ef750809020455q7b7ee6a8jc404b4970f660c50@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <65a6ef750809020455q7b7ee6a8jc404b4970f660c50@mail.gmail.com> Sender: linux-scsi-owner@vger.kernel.org To: Mark Nelson Cc: Jeff Garzik , linux-ide@vger.kernel.org, Mikael Pettersson , linux-scsi List-Id: linux-ide@vger.kernel.org Mark Nelson writes: > On Tue, Sep 2, 2008 at 9:19 PM, Jeff Garzik wrote: > > Mark Nelson wrote: > >> > >> Add an appropriate entry for the Promise PDC42819 controller. It has an > >> AHCI mode and seems to work correctly with board_ahci. > >> > >> This chip is found on Promise's FastTrak TX2650 (2 port) and TX4650 (4 > >> port) > >> software-based RAID cards (for which there is a binary driver, t3sas) and > >> can be found on some motherboards, for example the MSI K9A2 Platinum, > >> which calls the chip a Promise T3 controller. > >> > >> Signed-off-by: Mark Nelson > >> --- > >> Apparently this chip also supports SAS disks, will these work with the > >> ahci driver (I've only tested with normal desktop SATA disks)? > > > > ahci is definitely SATA-only, so I wonder how they modified AHCI to support > > SAS transport... > > That is a good question. From my understanding the controller is a SAS > controller that can drive SATA disks (as I guess all SAS controllers can > do...). Could it be that the controller can be setup to act as an AHCI > SATA controller or if the right registers are poked a SAS controller? Based on how the sata_promise-supported chips work I'd guess that they have dual programming interfaces with AHCI for JBOD SATA and a native one (perhaps just additional control registers) for SAS and raid.