Re: [PATCH v4 0/6] Add Auxiliary driver support

Leon Romanovsky
2022-11-10T10:53:59Z

On Wed, Nov 09, 2022 at 10:42:38AM -0800, Ajit Khaparde wrote:
> Add auxiliary device driver for Broadcom devices.
> The bnxt_en driver will register and initialize an aux device
> if RDMA is enabled in the underlying device.
> The bnxt_re driver will then probe and initialize the
> RoCE interfaces with the infiniband stack.
>
> We got rid of the bnxt_en_ops which the bnxt_re driver used to
> communicate with bnxt_en.
> Similarly We have tried to clean up most of the bnxt_ulp_ops.
> In most of the cases we used the functions and entry points provided
> by the auxiliary bus driver framework.
> And now these are the minimal functions needed to support the functionality.
>
> We will try to work on getting rid of the remaining if we find any
> other viable option in future.

I still see extra checks for something that was already checked in upper
functions, for example in bnxt_re_register_netdev() you check rdev, which
you already checked before.

However, the most important part is still existence of bnxt_ulp_ops,
which shows completely no-go thing - SR-IOV config in RDMA code.

302 static struct bnxt_ulp_ops bnxt_re_ulp_ops = {
303 .ulp_sriov_config = bnxt_re_sriov_config,
304 .ulp_irq_stop = bnxt_re_stop_irq,
305 .ulp_irq_restart = bnxt_re_start_irq
306 };

All PCI management logic and interfaces are needed to be inside eth part
of your driver and only that part should implement SR-IOV config. Once
user enabled SR-IOV, the PCI driver should create auxiliary devices for
each VF. These device will have RDMA capabilities and it will trigger RDMA
driver to bind to them.

Thanks