Jeff Garzik writes: > Mark Nelson wrote: > > On Thu, Sep 4, 2008 at 8:37 PM, Jeff Garzik <jeff@xxxxxxxxxx> wrote: > >> Mark Nelson wrote: > >>> On Tue, Sep 2, 2008 at 10:08 PM, Mikael Pettersson <mikpe@xxxxxxxx> wrote: > >>>> Mark Nelson writes: > >>>> > On Tue, Sep 2, 2008 at 9:19 PM, Jeff Garzik <jeff@xxxxxxxxxx> 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 <mdnelson8@xxxxxxxxx> > >>>> > >> --- > >>>> > >> 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. > >>>> > >>> That's interesting; and makes sense. I'm guessing that we won't end up > >>> with an open source driver that can do SAS on these chips then... But > >>> for now at least we can use them as SATA controllers and if Promise > >>> wants to come to the table with specs or datasheets they can in the > >>> future. I'm just happy to be able to use my eSATA ports (and perhaps > >>> the possibility of getting my hard disk off the SB600, although I should > >>> benchmark both controllers before jumping to any conclusions). > >> FWIW, I'll poke my Promise contacts, but they have gone mostly silent in the > >> past year, so don't get your hopes up... > > > > Thanks Jeff! > > > > No need for hope - we have ahci now :) > > Well, I still think this PCI ID addition leaves open the possibility > that plugging in a SAS disk could hang the system or similar misbehavior. Agreed, there's no telling what Promise-specific magic is needed to properly drive the T3. /Mikael -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
