+- ``rx_datapath`` [auto|efx|ef10|ef10_essb] (default **auto**)
+
+ Choose receive datapath implementation.
+ **auto** allows the driver itself to make a choice based on firmware
+ features available and required by the datapath implementation.
+ **efx** chooses libefx-based datapath which supports Rx scatter.
+ Supported for SFN7xxx, SFN8xxx and X2xxx family adapters only.
+ **ef10** chooses EF10 (SFN7xxx, SFN8xxx, X2xxx) native datapath which is
+ more efficient than libefx-based and provides richer packet type
+ classification.
+ **ef10_essb** chooses SFNX2xxx equal stride super-buffer datapath
+ which may be used on DPDK firmware variant only
+ (see notes about its limitations above).
+ **ef100** chooses EF100 native datapath which is the only supported
+ Rx datapath for EF100 architecture based NICs.
+
+- ``tx_datapath`` [auto|efx|ef10|ef10_simple|ef100] (default **auto**)
+
+ Choose transmit datapath implementation.
+ **auto** allows the driver itself to make a choice based on firmware
+ features available and required by the datapath implementation.
+ **efx** chooses libefx-based datapath which supports VLAN insertion
+ (full-feature firmware variant only), TSO and multi-segment mbufs.
+ Mbuf segments may come from different mempools, and mbuf reference
+ counters are treated responsibly.
+ Supported for SFN7xxx, SFN8xxx and X2xxx family adapters only.
+ **ef10** chooses EF10 (SFN7xxx, SFN8xxx, X2xxx) native datapath which is
+ more efficient than libefx-based but has no VLAN insertion support yet.
+ Mbuf segments may come from different mempools, and mbuf reference
+ counters are treated responsibly.
+ **ef10_simple** chooses EF10 (SFN7xxx, SFN8xxx, X2xxx) native datapath which
+ is even more faster then **ef10** but does not support multi-segment
+ mbufs, disallows multiple mempools and neglects mbuf reference counters.
+ **ef100** chooses EF100 native datapath which supports multi-segment
+ mbufs, VLAN insertion, inner/outer IPv4 and TCP/UDP checksum and TCP
+ segmentation offloads including VXLAN and GENEVE IPv4/IPv6 tunnels.
+
+- ``perf_profile`` [auto|throughput|low-latency] (default **throughput**)
+
+ Choose hardware tuning to be optimized for either throughput or
+ low-latency.
+ **auto** allows NIC firmware to make a choice based on
+ installed licenses and firmware variant configured using **sfboot**.
+
+- ``stats_update_period_ms`` [long] (default **1000**)
+
+ Adjust period in milliseconds to update port hardware statistics.
+ The accepted range is 0 to 65535. The value of **0** may be used
+ to disable periodic statistics update. One should note that it's
+ only possible to set an arbitrary value on SFN8xxx and X2xxx provided that
+ firmware version is 6.2.1.1033 or higher, otherwise any positive
+ value will select a fixed update period of **1000** milliseconds
+
+- ``fw_variant`` [dont-care|full-feature|ultra-low-latency|
+ capture-packed-stream|dpdk] (default **dont-care**)
+
+ Choose the preferred firmware variant to use.
+ The parameter is supported for SFN7xxX, SFN8xxx and X2xxx families only.
+ In order for the selected option to have an effect, the **sfboot** utility
+ must be configured with the **auto** firmware-variant option.
+ The preferred firmware variant applies to all ports on the NIC.
+ **dont-care** ensures that the driver can attach to an unprivileged function.
+ The datapath firmware type to use is controlled by the **sfboot**
+ utility.
+ **full-feature** chooses full featured firmware.
+ **ultra-low-latency** chooses firmware with fewer features but lower latency.
+ **capture-packed-stream** chooses firmware for SolarCapture packed stream
+ mode.
+ **dpdk** chooses DPDK firmware with equal stride super-buffer Rx mode
+ for higher Rx packet rate and packet marks support and firmware subvariant
+ without checksumming on transmit for higher Tx packet rate if
+ checksumming is not required.
+
+- ``rxd_wait_timeout_ns`` [long] (default **200 us**)
+
+ Adjust timeout in nanoseconds to head-of-line block to wait for
+ Rx descriptors.
+ The accepted range is 0 to 400 ms.
+ Flow control should be enabled to make it work.
+ The value of **0** disables it and packets are dropped immediately.
+ When a packet is dropped because of no Rx descriptors,
+ ``rx_nodesc_drop_cnt`` counter grows.
+ The feature is supported only by the DPDK firmware variant when equal
+ stride super-buffer Rx mode is used.
+
+
+Dynamic Logging Parameters
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+One may leverage EAL option "--log-level" to change default levels
+for the log types supported by the driver. The option is used with
+an argument typically consisting of two parts separated by a colon.
+
+Level value is the last part which takes a symbolic name (or integer).
+Log type is the former part which may shell match syntax.
+Depending on the choice of the expression, the given log level may
+be used either for some specific log type or for a subset of types.
+
+SFC EFX PMD provides the following log types available for control:
+
+- ``pmd.net.sfc.driver`` (default level is **notice**)
+
+ Affects driver-wide messages unrelated to any particular devices.
+
+- ``pmd.net.sfc.main`` (default level is **notice**)
+
+ Matches a subset of per-port log types registered during runtime.
+ A full name for a particular type may be obtained by appending a
+ dot and a PCI device identifier (``XXXX:XX:XX.X``) to the prefix.
+
+- ``pmd.net.sfc.mcdi`` (default level is **notice**)
+
+ Extra logging of the communication with the NIC's management CPU.
+ The format of the log is consumed by the Solarflare netlogdecode
+ cross-platform tool. May be managed per-port, as explained above.