Map physical PCIe device to the Phi co-processor card?

[Deutschmann__Frank]

Hello all,

Is it possible to map a PCIe card (or virtual function) resident on the host PCIe tree to the Phi co-processor device for direct access / control by the Phi device?  The PCIe card and the Phi are on the same PCIe root.  I would very much like to achieve direct communication between the Phi and another PCIe device which implements some key functionality for my application (the PCIe card is virtualization aware and surfaces multiple virtual functions).

Seems to me this should be possible, as I believe it currently works with InfiniBand HBA's - and similar functionality is available on Nvidia GPU's.

For bonus points, is it possible to do this in a system where the Phi is assigned to a Virtual Machine?

Thanks!

-frank

[Evan_P_Intel]

In principle, yes and yes. Batteries not included, however.

You are correct that, absent virtualization, direct communication (over the PCIe bus, without involving host memory) is well supported in the current driver stack both between pairs of Xeon Phis and between a Xeon Phi and supported Infiniband HCA, assuming the system they're plugged into was appropriately chosen.

You may find these earlier threads relevant:

• https://software.intel.com/en-us/forums/topic/540368
• https://software.intel.com/en-us/forums/topic/517488#comment-1793615
• https://software.intel.com/en-us/forums/topic/394321#comment-1788686