Current-Users archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: Kernel only sees 1 SATA channel out of 4 - nv520 chip

On Fri, Jan 11, 2008 at 01:00:50AM -0700, Art Lemasters wrote:
>   I've installed an Abit AN52 motherboard. It has an "nvidia nf520
> single chip." It only sees one SATA channel out of four. The BIOS
> sees two hard drives. FreeBSD (live cd) sees both drives (two
> drives plugged into two of the four SATA interfaces on the motherboard.
> My guess from looking at the FreeBSD dmesg (if the dmesg was accurate
> enough) is that there are two onboard SATA controllers, each with two
> channels (four interfaces on the motherboard).
> Here's a dmesg with a current kernel. I have a 4.0 userland installed,
> and the compile and installation of the current kernel was only to see
> if the current kernel can see more of the buses than 4.0.
> CC replies to me, especially if you want me to do any diagnostic
> configs and send or post the results. Also let me know if this should
> be copied to the tech-kern or another list.


Okay, I've looked at the NetBSD, FreeBSD, and OpenBSD code,
we're the only one that tries to use the native-SATA registers
to detect the drive with this chip.

Anyway, I think we're wrong to try to use these registers in this
case.  I believe that, unlike some other nvidia sata controllers,
this model uses master+slave emulation.  The native SATA registers
are currently subregioned in a way that is unlikely to actually
work in this mode.  And the bogus detected speed is an indication
that this is the case.

Please file a PR (perhaps referencing this message

        Jonathan Kollasch

Attachment: pgpc9SfKxYTUc.pgp
Description: PGP signature

Home | Main Index | Thread Index | Old Index