Asus P5B: Nonlinear AHCI ports mapping on ICH8 ?

freemanix · n00b Joined: 28 Oct 2006 Posts: 5

Hi all,

I am a "victim" of ASUS P5B motheboard. I successfully solved those JMicron PATA IDE problems thanks to help of KernelOfTruth's modified Live CD. But, I am using 4x 250GB of SATA drivers, which I want to connect to those 2x red and 2x black connectors on board. These are controlled by Intel AHCI compatible ICH8 controller.

When I set SATA mode to AHCI in BIOS, latest 2.6.19-mm-rc2 kernel finds 4 ports AHCI controller, but only ata1 and ata2 works, ata3 and ata4 are not recognized. So I end with 2 of 4 drives found.

After a lot of "analyzing", I found that BIOS maps the ports in NON-LINEAR manner, these four ports are at indexes 0,1 and 4,5 (skipping 2 and 3). This probably causes a problems to kernel AHCI ports detection code. I found this discussion on linux.kernel, which is closely related to my problem: http://www.uwsg.iu.edu/hypermail/linux/kernel/0609.2/0105.html. There was a patch included, but also a warning that this fix may not be a good approach and may not work after controller reset.

Please, is there anybody successfully using ASUS P5B with 4 drives on ICH8? What kernel to use? What patch? Is some fix planned to upcoming kernels?

aceFruchtsaft · Posted: Mon Oct 30, 2006 1:10 am Post subject:

Why don't you connect all drives to the 4 red connectors instead?

Ich have 3 HDDs an one SATA-DVDRW connected to the red connectors and basically every kernel so far hast detected them. I use "Raid" instead of "Ahci" though, which shouldn't matter since it does not work in Linux anyway as the drives are treated as separate block devices.

freemanix · n00b Joined: 28 Oct 2006 Posts: 5

That's simple - there are only TWO RED connectors on my ASUS P2B. The color mapping probably indicates what ports will be master/slave simulated in BIOS if "Compatibility mode" would have been switched on.

Meantime I found that the one-month old patch mentioned in linux kernel mailing list is not anymore applicable to kernel 2.6.19-rc2.

freemanix · n00b Joined: 28 Oct 2006 Posts: 5

Sorry about the typo in my previous post - I have latest ASUS P5B (dual core support) board, not the mentioned P2B. I checked that "Deluxe" version has 4 red ports, but mine in "standard" and has only 2 red a and 2 black (plus some JMicron black ones).

aceFruchtsaft · Posted: Mon Oct 30, 2006 11:39 am Post subject:

robbat2 · Developer Joined: 19 Feb 2003 Posts: 82

Look at the linux-ide mailing list, and see the most recent version of the AHCI non-linear patches posted by Tejun Heo.