..  SPDX-License-Identifier: BSD-3-Clause
    Copyright 2015 - 2016 CESNET

SZEDATA2 poll mode driver library
=================================

The SZEDATA2 poll mode driver library implements support for the Netcope
FPGA Boards (**NFB-***), FPGA-based programmable NICs.
The SZEDATA2 PMD uses interface provided by the libsze2 library to communicate
with the NFB cards over the sze2 layer.

More information about the
`NFB cards <http://www.netcope.com/en/products/fpga-boards>`_
and used technology
(`Netcope Development Kit <http://www.netcope.com/en/products/fpga-development-kit>`_)
can be found on the `Netcope Technologies website <http://www.netcope.com/>`_.

.. note::

   This driver has external dependencies.
   Therefore it is disabled in default configuration files.
   It can be enabled by setting ``CONFIG_RTE_LIBRTE_PMD_SZEDATA2=y``
   and recompiling.

.. note::

   Currently the driver is supported only on x86_64 architectures.
   Only x86_64 versions of the external libraries are provided.

Prerequisites
-------------

This PMD requires kernel modules which are responsible for initialization and
allocation of resources needed for sze2 layer function.
Communication between PMD and kernel modules is mediated by libsze2 library.
These kernel modules and library are not part of DPDK and must be installed
separately:

*  **libsze2 library**

   The library provides API for initialization of sze2 transfers, receiving and
   transmitting data segments.

*  **Kernel modules**

   * combov3
   * szedata2_cv3

   Kernel modules manage initialization of hardware, allocation and
   sharing of resources for user space applications.

Information about getting the dependencies can be found `here
<http://www.netcope.com/en/company/community-support/dpdk-libsze2>`_.

Configuration
-------------

These configuration options can be modified before compilation in the
``.config`` file:

*  ``CONFIG_RTE_LIBRTE_PMD_SZEDATA2`` default value: **n**

   Value **y** enables compilation of szedata2 PMD.

*  ``CONFIG_RTE_LIBRTE_PMD_SZEDATA2_AS`` default value: **0**

   This option defines type of firmware address space and must be set
   according to the used card and mode.
   Currently supported values are:

   * **0** - for cards (modes):

      * NFB-100G1 (100G1)

   * **1** - for cards (modes):

      * NFB-100G2Q (100G1)

   * **2** - for cards (modes):

      * NFB-40G2 (40G2)
      * NFB-100G2C (100G2)
      * NFB-100G2Q (40G2)

   * **3** - for cards (modes):

      * NFB-40G2 (10G8)
      * NFB-100G2Q (10G8)

   * **4** - for cards (modes):

      * NFB-100G1 (10G10)

   * **5** - for experimental firmwares and future use

Using the SZEDATA2 PMD
----------------------

From DPDK version 16.04 the type of SZEDATA2 PMD is changed to PMD_PDEV.
SZEDATA2 device is automatically recognized during EAL initialization.
No special command line options are needed.

Kernel modules have to be loaded before running the DPDK application.

Example of usage
----------------

Read packets from 0. and 1. receive channel and write them to 0. and 1.
transmit channel:

.. code-block:: console

   $RTE_TARGET/app/testpmd -l 0-3 -n 2 \
   -- --port-topology=chained --rxq=2 --txq=2 --nb-cores=2 -i -a

Example output:

.. code-block:: console

   [...]
   EAL: PCI device 0000:06:00.0 on NUMA socket -1
   EAL:   probe driver: 1b26:c1c1 rte_szedata2_pmd
   PMD: Initializing szedata2 device (0000:06:00.0)
   PMD: SZEDATA2 path: /dev/szedataII0
   PMD: Available DMA channels RX: 8 TX: 8
   PMD: resource0 phys_addr = 0xe8000000 len = 134217728 virt addr = 7f48f8000000
   PMD: szedata2 device (0000:06:00.0) successfully initialized
   Interactive-mode selected
   Auto-start selected
   Configuring Port 0 (socket 0)
   Port 0: 00:11:17:00:00:00
   Checking link statuses...
   Port 0 Link Up - speed 10000 Mbps - full-duplex
   Done
   Start automatic packet forwarding
     io packet forwarding - CRC stripping disabled - packets/burst=32
     nb forwarding cores=2 - nb forwarding ports=1
     RX queues=2 - RX desc=128 - RX free threshold=0
     RX threshold registers: pthresh=0 hthresh=0 wthresh=0
     TX queues=2 - TX desc=512 - TX free threshold=0
     TX threshold registers: pthresh=0 hthresh=0 wthresh=0
     TX RS bit threshold=0 - TXQ flags=0x0
   testpmd>