+- ``Support multiple driver`` (default ``disable``)
+
+ There was a multiple driver support issue during use of 700 series Ethernet
+ Adapter with both Linux kernel and DPDK PMD. To fix this issue, ``devargs``
+ parameter ``support-multi-driver`` is introduced, for example::
+
+ -w 84:00.0,support-multi-driver=1
+
+ With the above configuration, DPDK PMD will not change global registers, and
+ will switch PF interrupt from IntN to Int0 to avoid interrupt conflict between
+ DPDK and Linux Kernel.
+
+- ``Support VF Port Representor`` (default ``not enabled``)
+
+ The i40e PF PMD supports the creation of VF port representors for the control
+ and monitoring of i40e virtual function devices. Each port representor
+ corresponds to a single virtual function of that device. Using the ``devargs``
+ option ``representor`` the user can specify which virtual functions to create
+ port representors for on initialization of the PF PMD by passing the VF IDs of
+ the VFs which are required.::
+
+ -w DBDF,representor=[0,1,4]
+
+ Currently hot-plugging of representor ports is not supported so all required
+ representors must be specified on the creation of the PF.
+
+- ``Use latest supported vector`` (default ``disable``)
+
+ Latest supported vector path may not always get the best perf so vector path was
+ recommended to use only on later platform. But users may want the latest vector path
+ since it can get better perf in some real work loading cases. So ``devargs`` param
+ ``use-latest-supported-vec`` is introduced, for example::
+
+ -w 84:00.0,use-latest-supported-vec=1
+
+Vector RX Pre-conditions
+~~~~~~~~~~~~~~~~~~~~~~~~
+For Vector RX it is assumed that the number of descriptor rings will be a power
+of 2. With this pre-condition, the ring pointer can easily scroll back to the
+head after hitting the tail without a conditional check. In addition Vector RX
+can use this assumption to do a bit mask using ``ring_size - 1``.