IOAT 4.0 driver not supported on Intel 5000 chipset

From: Anshuman Khandual
Date: Wed Jan 25 2017 - 00:46:39 EST


Hello Vinod/Dave,

I have an old X86 system with 'Intel(R) Xeon(R) CPU X5450' which has
'5000 Series Chipset'. The latest mainline IOAT driver does not work
on it. Dont see /sys/class/dma getting filled up with channel details
even if I manually load both dca.ko followed by ioatdma.ko drivers
after the system boots. As it was working on a old distro kernel like
3.10, did a git bisect to figure out that the support was removed for
older IOAT HW around August 2015 with the following commits.

commit 85596a19478da5125f3471a0c474b3f05a78e390
Author: Dave Jiang <dave.jiang@xxxxxxxxx>
Date: Tue Aug 11 08:48:10 2015 -0700

dmaengine: ioatdma: remove ioat1 specific code

Cleaning up of ioat1 specific code as it is no longer supported

Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Acked-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx>

d73f277b329f46c13527c1090808421828671596 is the first bad commit
commit d73f277b329f46c13527c1090808421828671596
Author: Dave Jiang <dave.jiang@xxxxxxxxx>
Date: Tue Aug 11 08:48:04 2015 -0700

dmaengine: ioatdma: deprecating and removal of old ioatdma devices

Removal of any devices that are ioatdma pre-3.0. This is the first step
in attempting to clean up the ioatdma driver and remove hw no longer
supported.

Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Acked-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx>

I intend to use the HW with mainline kernel. Is there any work around
which can make it happen ?

Regards
Anshuman