2. BBDEV null Poll Mode Driver

The (baseband_null) is a bbdev poll mode driver which provides a minimal implementation of a software bbdev device. As a null device it does not modify the data in the mbuf on which the bbdev operation is to operate and it only works for operation type RTE_BBDEV_OP_NONE.

When a burst of mbufs is submitted to a bbdev null PMD for processing then each mbuf in the burst will be enqueued in an internal buffer ring to be collected on a dequeue call.

2.1. Limitations

  • In-place operations for Turbo encode and decode are not supported

2.2. Installation

The bbdev null PMD is enabled and built by default in both the Linux and FreeBSD builds.

2.3. Initialization

To use the PMD in an application, user must:

  • Call rte_vdev_init("baseband_null") within the application.
  • Use --vdev="baseband_null" in the EAL options, which will call rte_vdev_init() internally.

The following parameters (all optional) can be provided in the previous two calls:

  • socket_id: Specify the socket where the memory for the device is going to be allocated (by default, socket_id will be the socket where the core that is creating the PMD is running on).
  • max_nb_queues: Specify the maximum number of queues in the device (default is RTE_MAX_LCORE).

2.3.1. Example:

./test-bbdev.py -e="--vdev=baseband_null,socket_id=0,max_nb_queues=8"