1.. SPDX-License-Identifier: BSD-3-Clause 2 Copyright(c) 2017 Intel Corporation 3 4BBDEV null Poll Mode Driver 5============================ 6 7The (**baseband_null**) is a bbdev poll mode driver which provides a minimal 8implementation of a software bbdev device. As a null device it does not modify 9the data in the mbuf on which the bbdev operation is to operate and it only 10works for operation type ``RTE_BBDEV_OP_NONE``. 11 12When a burst of mbufs is submitted to a *bbdev null PMD* for processing then 13each mbuf in the burst will be enqueued in an internal buffer ring to be 14collected on a dequeue call. 15 16 17Limitations 18----------- 19 20* In-place operations for Turbo encode and decode are not supported 21 22Installation 23------------ 24 25The *bbdev null PMD* is enabled and built by default in both the Linux and 26FreeBSD builds. 27 28Initialization 29-------------- 30 31To use the PMD in an application, user must: 32 33- Call ``rte_vdev_init("baseband_null")`` within the application. 34 35- Use ``--vdev="baseband_null"`` in the EAL options, which will call ``rte_vdev_init()`` internally. 36 37The following parameters (all optional) can be provided in the previous two calls: 38 39* ``socket_id``: Specify the socket where the memory for the device is going to be allocated 40 (by default, *socket_id* will be the socket where the core that is creating the PMD is running on). 41 42* ``max_nb_queues``: Specify the maximum number of queues in the device (default is ``RTE_MAX_LCORE``). 43 44Example: 45~~~~~~~~ 46 47.. code-block:: console 48 49 ./test-bbdev.py -e="--vdev=baseband_null,socket_id=0,max_nb_queues=8" 50