8. NXP LA12xx Poll Mode Driver

The BBDEV LA12xx poll mode driver (PMD) supports an implementation for offloading High Phy processing functions like LDPC Encode / Decode 5GNR wireless acceleration function, using PCI based LA12xx Software defined radio.

More information can be found at NXP Official Website.

8.1. Features

LA12xx PMD supports the following features:

  • Maximum of 8 LDPC decode (UL) queues
  • Maximum of 8 LDPC encode (DL) queues
  • PCIe Gen-3 x8 Interface

8.2. Installation

Section 3 of the DPDK manual provides instructions on installing and compiling DPDK.

DPDK requires hugepages to be configured as detailed in section 2 of the DPDK manual.

8.3. Initialization

The device can be listed on the host console with:

Use the following lspci command to get the multiple LA12xx processor ids. The device ID of the LA12xx baseband processor is “1c30”.

sudo lspci -nn

… 0001:01:00.0 Power PC [0b20]: Freescale Semiconductor Inc Device [1957:1c30] ( rev 10) … 0002:01:00.0 Power PC [0b20]: Freescale Semiconductor Inc Device [1957:1c30] ( rev 10)

8.4. Prerequisites

Currently supported by DPDK:

  • NXP LA1224 BSP 1.0+.
  • NXP LA1224 PCIe Modem card connected to ARM host.
  • Follow the DPDK Getting Started Guide for Linux to setup the basic DPDK environment.
  • Use dev arg option modem=0 to identify the modem instance for a given device. This is required only if more than 1 modem cards are attached to host. this is optional and the default value is 0. e.g. --vdev=baseband_la12xx,modem=0
  • Use dev arg option max_nb_queues=x to specify the maximum number of queues to be used for communication with offload device i.e. modem. default is 16. e.g. --vdev=baseband_la12xx,max_nb_queues=4

8.5. Enabling logs

For enabling logs, use the following EAL parameter:

./your_bbdev_application <EAL args> --log-level=la12xx:<level>

Using bb.la12xx as log matching criteria, all Baseband PMD logs can be enabled which are lower than logging level.

8.6. Test Application

BBDEV provides a test application, test-bbdev.py and range of test data for testing the functionality of LA12xx for FEC encode and decode, depending on the device capabilities. The test application is located under app->test-bbdev folder and has the following options:

"-p", "--testapp-path": specifies path to the bbdev test app.
"-e", "--eal-params"  : EAL arguments which are passed to the test app.
"-t", "--timeout"     : Timeout in seconds (default=300).
"-c", "--test-cases"  : Defines test cases to run. Run all if not specified.
"-v", "--test-vector" : Test vector path (default=dpdk_path+/app/test-bbdev/test_vectors/bbdev_null.data).
"-n", "--num-ops"     : Number of operations to process on device (default=32).
"-b", "--burst-size"  : Operations enqueue/dequeue burst size (default=32).
"-s", "--snr"         : SNR in dB used when generating LLRs for bler tests.
"-s", "--iter_max"    : Number of iterations for LDPC decoder.
"-l", "--num-lcores"  : Number of lcores to run (default=16).
"-i", "--init-device" : Initialise PF device with default values.

To execute the test application tool using simple decode or encode data, type one of the following:

./test-bbdev.py -e="--vdev=baseband_la12xx,socket_id=0,max_nb_queues=8" -c validation -n 64 -b 1 -v ./ldpc_dec_default.data
./test-bbdev.py -e="--vdev=baseband_la12xx,socket_id=0,max_nb_queues=8" -c validation -n 64 -b 1 -v ./ldpc_enc_default.data

The test application test-bbdev.py, supports the ability to configure the PF device with a default set of values, if the “-i” or “- -init-device” option is included. The default values are defined in test_bbdev_perf.c.

8.6.1. Test Vectors

In addition to the simple LDPC decoder and LDPC encoder tests, bbdev also provides a range of additional tests under the test_vectors folder, which may be useful. The results of these tests will depend on the LA12xx FEC capabilities which may cause some testcases to be skipped, but no failure should be reported.