Description of problem:

The most recent RHEL4 beta kernel (2.6.9-6.37.EL) includes support for the ICH7
SATA controllers, but this fails to work properly on my hardware. (HP xw4300
workstation, ATA controller set to 'separate controller mode' in BIOS)

The kernel reports the error message:

ata_piix: probe of 0000:00:1f.2 failed with error -5

This problem has already been reported on the linux-kernel mailing list. A patch
was posted to the list which solves the problem for me, however this patch has
not yet made it into the official kernel, or the 'libata' repository maintained
by Jeff Garzik.

Version-Release number of selected component (if applicable):

RHEL4 beta kernel, 2.6.9-6.37.EL

How reproducible:

Always

Steps to Reproduce:
1. try to load the ata_piix driver with an ICH7 controller (8086:27c0)
  
Actual results:

The kernel reports error message:
ata_piix: probe of 0000:00:1f.2 failed with error -5

and does not attach the SATA controller.

Expected results:

the SATA controller should work

Additional info:


This problem was originally reported by Greg Felix on the linux kernel mailing
list. To find the original message search for:

From: 'Greg Felix <gregfelixlkml@gmail.com>'
Subject: 'PROBLEM: ICH7 SATA drive not detected.'
Date: 2005-02-26

Here is a link to the original message:

http://marc.theaimsgroup.com/?l=linux-kernel&m=110938051022980



Greg later posted a patch which solves the problem (for me as well as for him):

References for this posting:

From: 'Greg Felix <gregfelixlkml@gmail.com>'
Subject: '[PATCH] ata_piix.c: check PCI sub-class code before AHCI disabling'
Date: 2005-03-05

Here is a link:

http://marc.theaimsgroup.com/?l=linux-ide&m=110999169405779



I included a copy of the posting with the patch as an attachment. Note that the
patch is whitespace-damaged, but otherwise applies to the current RHEL4 beta
kernel (2.6.9-6.37.EL).

Applying this patch solves the problem for me, and ata_piix works properly.