1. Marvell CNXK BPHY Driver

CN10K/CN9K Fusion product families offer an internal BPHY unit which provides set of hardware accelerators for performing baseband related operations. Connectivity to the outside world happens through a block called RFOE which is backed by ethernet I/O block called CGX or RPM (depending on the chip version). RFOE stands for Radio Frequency Over Ethernet and provides support for IEEE 1904.3 (RoE) standard.

1.1. Features

The BPHY CGX/RPM implements following features in the rawdev API:

  • Access to BPHY CGX/RPM via a set of predefined messages
  • Access to BPHY memory
  • Custom interrupt handlers

1.2. Device Setup

The BPHY CGX/RPM devices will need to be bound to a user-space IO driver for use. The script dpdk-devbind.py script included with DPDK can be used to view the state of the devices and to bind them to a suitable DPDK-supported kernel driver. When querying the status of the devices, they will appear under the category of “Misc (rawdev) devices”, i.e. the command dpdk-devbind.py --status-dev misc can be used to see the state of those devices alone.

Before performing actual data transfer one needs to first retrieve number of available queues with rte_rawdev_queue_count() and capacity of each using rte_rawdev_queue_conf_get().

To perform data transfer use standard rte_rawdev_enqueue_buffers() and rte_rawdev_dequeue_buffers() APIs. Not all messages produce sensible responses hence dequeuing is not always necessary.

1.3. BPHY CGX/RPM PMD

BPHY CGX/RPM PMD accepts struct cnxk_bphy_cgx_msg messages which differ by type and payload. Message types along with description are listed below. As for the usage examples please refer to cnxk_bphy_cgx_dev_selftest().

1.3.2. Change internal loopback state

Message is used to enable or disable internal loopback.

Message must have type set to CNXK_BPHY_CGX_MSG_TYPE_INTLBK_ENABLE or CNXK_BPHY_CGX_MSG_TYPE_INTLBK_DISABLE. Former will activate internal loopback while the latter will do the opposite.

1.3.3. Change PTP RX state

Message is used to enable or disable PTP mode.

Message must have type set to CNXK_BPHY_CGX_MSG_TYPE_PTP_RX_ENABLE or CNXK_BPHY_CGX_MSG_TYPE_PTP_RX_DISABLE. Former will enable PTP while the latter will do the opposite.

1.3.6. Start or stop RX/TX

Message is used to start or stop accepting traffic.

Message must have type set to CNXK_BPHY_CGX_MSG_TYPE_START_RXTX or CNXK_BPHY_CGX_MSG_TYPE_STOP_RXTX. Former will enable traffic while the latter will do the opposite.

1.3.7. Change mode from eCPRI to CPRI

Message is used to change operating mode from eCPRI to CPRI along with other settings.

Message must have type set to CNXK_BPHY_CGX_MSG_TYPE_CPRI_MODE_CHANGE. Prior to sending actual message payload i.e struct cnxk_bphy_cgx_msg_cpri_mode_change needs to be filled with relevant information.

1.3.8. Enable TX for CPRI SERDES

Message is used to enable TX for SERDES configured in CPRI mode.

Message must have type set to CNXK_BPHY_CGX_MSG_TYPE_CPRI_TX_CONTROL. Prior to sending actual message payload i.e struct cnxk_bphy_cgx_msg_cpri_mode_tx_ctrl needs to be filled with relevant information.

1.3.9. Change CPRI misc settings

Message is used to change misc CPRI settings, for example to reset RX state machine on CPRI SERDES.

Message must have type set to CNXK_BPHY_CGX_MSG_TYPE_CPRI_MODE_MISC. Prior to sending actual message payload i.e struct cnxk_bphy_cgx_msg_cpri_mode_misc needs to be filled with relevant information.

1.4. BPHY PMD

BPHY PMD accepts struct cnxk_bphy_irq_msg messages which differ by type and payload. Message types along with description are listed below. For some usage examples please refer to bphy_rawdev_selftest().

1.4.1. Initialize or finalize interrupt handling

Message is used to setup low level interrupt handling.

Message must have type set to CNXK_BPHY_IRQ_MSG_TYPE_INIT or CNXK_BPHY_IRQ_MSG_TYPE_FINI. The former will setup low level interrupt handling while the latter will tear everything down. There are also two convenience functions namely rte_pmd_bphy_intr_init() and rte_pmd_bphy_intr_fini() that take care of all details.

1.4.2. Register or remove interrupt handler

Message is used setup custom interrupt handler.

Message must have type set to CNXK_BPHY_IRQ_MSG_TYPE_REGISTER or CNXK_BPHY_IRQ_MSG_TYPE_UNREGISTER. The former will register an interrupt handler while the latter will remove it. Prior sending actual message payload i.e struct cnxk_bphy_irq_info needs to be filled with relevant information. There are also two convenience functions namely rte_pmd_bphy_intr_register() and rte_pmd_bphy_intr_unregister() that take care of all details.

1.4.3. Get device memory

Message is used to read device MMIO address.

Message must have type set to CNXK_BPHY_IRQ_MSG_TYPE_MEM_GET. There’s a convenience function rte_pmd_bphy_intr_mem_get() available that takes care of retrieving that address.

1.5. Self test

On EAL initialization BPHY and BPHY CGX/RPM devices will be probed and populated into the raw devices. The rawdev ID of the device can be obtained using invocation of rte_rawdev_get_dev_id("NAME:x") from the test application, where:

  • NAME is the desired subsystem: use “BPHY” for regular, and “BPHY_CGX” for RFOE module.
  • x is the device’s bus id specified in “bus:device.func” (BDF) format. BDF follows convention used by lspci i.e bus, device and func are specified using respectively two, two and one hex digit(s).

Use this identifier for further rawdev function calls.

Selftest rawdev API can be used to verify the BPHY and BPHY CGX/RPM functionality.