Re: Creating new RDMA driver for habanalabs

[Leon Romanovsky <leon@kernel.org>]

On Sun, Aug 22, 2021 at 12:40:26PM +0300, Oded Gabbay wrote:
> Hi Jason,
> 
> I think that about a year ago we talked about the custom RDMA code of
> habanalabs. I tried to upstream it and you, rightfully, rejected that.
> 
> Now that I have enough b/w to do this work, I want to start writing a
> proper RDMA driver for the habanalabs Gaudi device, which I will be
> able to upstream to the infiniband subsystem.
> 
> I don't know if you remember but the Gaudi h/w is somewhat limited in
> its RDMA capabilities. We are not selling a stand-alone NIC :) We just
> use RDMA (or more precisely, ROCEv2) to connect between Gaudi devices.
> 
> I'm sure I will have more specific questions down the line, but I had
> hoped you could point me to a basic/not-too-complex existing driver
> that I can use as a modern template. I'm also aware that I will need
> to write matching code in rdma-core.

drivers/infiniband/hw/efa can be seen as a good example.

> 
> Also, I would like to add we will use the auxiliary bus feature to
> connect between this driver, the main (compute) driver and the
> Ethernet driver (which we are going to publish soon I hope).
> 
> Thanks,
> Oded