Re: Intel QAT 8970 accel card on ARM Ampere Server

[David Marchand <david.marchand@redhat.com>]

Hello Patrick,

On Thu, Mar 7, 2024 at 6:27 AM Patrick Robb <probb@iol.unh.edu> wrote:
> 1. As Dharmik and David discussed, there are some QAT devices that
> need VFIO denylist=1. To account for this, in cryptodev_common.py
> (which the crypto perf testsuite imports), we need to add:
>
> given the c62x device id is 37c8
>
> if dev_id in ["37c8", "435", "19e2"]:
>     test_case.dut.send_expect('modprobe -r vfio_iommu_type1; modprobe
> -r vfio_pci; modprobe -r vfio_virqfd; modprobe -r vfio', '# ', 5)
>     test_case.dut.send_expect('modprobe vfio-pci disable_denylist=1
> enable_sriov=1 vfio-pci.ids=8086:37c9', '# ', 5)
>     test_case.dut.send_expect('echo "1" | tee
> /sys/module/vfio/parameters/enable_unsafe_noiommu_mode', '# ', 5)
>
> In order to maintain the custom vfio loading Dharmik recommended. The
> latter two dev ids in that list are for DH895XCC and C3XXX, since they
> are also included in
> https://github.com/torvalds/linux/commit/50173329c8cc0c892eaa7a9d0f0692ac39cd7b04
>
> David and Dharmik, I think this is correct, but please chime in if it isn't.

You probably missed one question I had, mixed with my grmbl about
disable_denylist.
"""
However, I don't think the vfio-pci.ids syntax works for passing parameters.
And in any case, why do you need to set this initial list?
Binding devices (using either driverctl or dpdk-devbind.py) to
vfio-pci should be done the "usual" way, or is there some special case
again for QAT?
"""

Re-reading vfio-pci kernel parsing code, the syntax for vfio-pci.ids
seems ok, my bad.

But I am still not clear if there is a need for a special case here.
bind_qat_device() calls test_case.dut.bind_eventdev_port which itself
calls dpdk-devbind to bind the VF to vfio-pci.

So here, on the topic of loading vfio-pci wrt the QAT quirk, you only need:
# modprobe vfio-pci disable_denylist=1 enable_sriov=1


-- 
David Marchand