Re: [RFC PATCH net-next 19/19] pds_vdpa: add Kconfig entry and pds_vdpa.rst

[Jason Wang <jasowang@redhat.com>]

On Sat, Nov 19, 2022 at 6:57 AM Shannon Nelson <snelson@pensando.io> wrote:
>
> Signed-off-by: Shannon Nelson <snelson@pensando.io>
> ---
>  .../ethernet/pensando/pds_vdpa.rst            | 85 +++++++++++++++++++
>  MAINTAINERS                                   |  1 +
>  drivers/vdpa/Kconfig                          |  7 ++
>  3 files changed, 93 insertions(+)
>  create mode 100644 Documentation/networking/device_drivers/ethernet/pensando/pds_vdpa.rst
>
> diff --git a/Documentation/networking/device_drivers/ethernet/pensando/pds_vdpa.rst b/Documentation/networking/device_drivers/ethernet/pensando/pds_vdpa.rst
> new file mode 100644
> index 000000000000..c517f337d212
> --- /dev/null
> +++ b/Documentation/networking/device_drivers/ethernet/pensando/pds_vdpa.rst
> @@ -0,0 +1,85 @@
> +.. SPDX-License-Identifier: GPL-2.0+
> +.. note: can be edited and viewed with /usr/bin/formiko-vim
> +
> +==========================================================
> +PCI vDPA driver for the Pensando(R) DSC adapter family
> +==========================================================
> +
> +Pensando vDPA VF Device Driver
> +Copyright(c) 2022 Pensando Systems, Inc
> +
> +Overview
> +========
> +
> +The ``pds_vdpa`` driver is a PCI and auxiliary bus driver and supplies
> +a vDPA device for use by the virtio network stack.  It is used with
> +the Pensando Virtual Function devices that offer vDPA and virtio queue
> +services.  It depends on the ``pds_core`` driver and hardware for the PF
> +and for device configuration services.
> +
> +Using the device
> +================
> +
> +The ``pds_vdpa`` device is enabled via multiple configuration steps and
> +depends on the ``pds_core`` driver to create and enable SR-IOV Virtual
> +Function devices.
> +
> +Shown below are the steps to bind the driver to a VF and also to the
> +associated auxiliary device created by the ``pds_core`` driver. This
> +example assumes the pds_core and pds_vdpa modules are already
> +loaded.
> +
> +.. code-block:: bash
> +
> +  #!/bin/bash
> +
> +  modprobe pds_core
> +  modprobe pds_vdpa
> +
> +  PF_BDF=`grep "vDPA.*1" /sys/kernel/debug/pds_core/*/viftypes | head -1 | awk -F / '{print $6}'`
> +
> +  # Enable vDPA VF auxiliary device(s) in the PF
> +  devlink dev param set pci/$PF_BDF name enable_vnet value true cmode runtime
> +
> +  # Create a VF for vDPA use
> +  echo 1 > /sys/bus/pci/drivers/pds_core/$PF_BDF/sriov_numvfs
> +
> +  # Find the vDPA services/devices available
> +  PDS_VDPA_MGMT=`vdpa mgmtdev show | grep vDPA | head -1 | cut -d: -f1`
> +
> +  # Create a vDPA device for use in virtio network configurations
> +  vdpa dev add name vdpa1 mgmtdev $PDS_VDPA_MGMT mac 00:11:22:33:44:55
> +
> +  # Set up an ethernet interface on the vdpa device
> +  modprobe virtio_vdpa
> +
> +
> +
> +Enabling the driver
> +===================
> +
> +The driver is enabled via the standard kernel configuration system,
> +using the make command::
> +
> +  make oldconfig/menuconfig/etc.
> +
> +The driver is located in the menu structure at:
> +
> +  -> Device Drivers
> +    -> Network device support (NETDEVICES [=y])
> +      -> Ethernet driver support
> +        -> Pensando devices
> +          -> Pensando Ethernet PDS_VDPA Support
> +
> +Support
> +=======
> +
> +For general Linux networking support, please use the netdev mailing
> +list, which is monitored by Pensando personnel::
> +
> +  netdev@vger.kernel.org
> +
> +For more specific support needs, please use the Pensando driver support
> +email::
> +
> +  drivers@pensando.io
> diff --git a/MAINTAINERS b/MAINTAINERS
> index a4f989fa8192..a4d96e854757 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -16152,6 +16152,7 @@ L:      netdev@vger.kernel.org
>  S:     Supported
>  F:     Documentation/networking/device_drivers/ethernet/pensando/
>  F:     drivers/net/ethernet/pensando/
> +F:     drivers/vdpa/pds/
>  F:     include/linux/pds/
>
>  PER-CPU MEMORY ALLOCATOR
> diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
> index 50f45d037611..1c44df18f3da 100644
> --- a/drivers/vdpa/Kconfig
> +++ b/drivers/vdpa/Kconfig
> @@ -86,4 +86,11 @@ config ALIBABA_ENI_VDPA
>           VDPA driver for Alibaba ENI (Elastic Network Interface) which is built upon
>           virtio 0.9.5 specification.
>
> +config PDS_VDPA
> +       tristate "vDPA driver for Pensando DSC devices"
> +       select VHOST_RING

Any reason it needs to select on vringh?

Thanks

> +       depends on PDS_CORE
> +       help
> +         VDPA network driver for Pensando's PDS Core devices.
> +
>  endif # VDPA
> --
> 2.17.1
>