docs: Add vmxmet3 driver

Change-Id: I96425804c310a1ac1b7f5f12bb636e591c7bd429
Signed-off-by: jdenisco <jdenisco@cisco.com>

2 files changed, 129 insertions, 0 deletions

diff --git a/docs/usecases/index.rst b/docs/usecases/index.rst
index 3dabd78ca06..614f0026094 100644
--- a/docs/usecases/index.rst
+++ b/docs/usecases/index.rst
@@ -12,6 +12,7 @@ extensive list, but should give a sampling of the many features contained in FD.
    containers
    simpleperf/index.rst
    vhost/index.rst
+   vmxnet3
    homegateway
    contiv/index.rst
    networksim
diff --git a/docs/usecases/vmxnet3.rst b/docs/usecases/vmxnet3.rst
new file mode 100644
index 00000000000..7e7210f83fc
--- /dev/null
+++ b/docs/usecases/vmxnet3.rst
@@ -0,0 +1,128 @@
+.. _vmxnet3:
+
+VPP with VMware/Vmxnet3
+=======================
+
+This section describes a native Vmxnet3 driver that is included with VPP.
+This driver is written as a plugin and is found in src/plugin/vmxnet3.
+
+Advantages
+----------
+
+The native VPP native vmxnet3 driver provides the following features
+that are not provided with the standard dpdk vmxnet3 driver.
+
+-  Interrupt mode
+-  Adaptive mode
+-  TSO/LRO mode
+
+Does not support
+----------------
+
+This driver does yet support the following features.
+
+-  NUMA support
+-  RSS/multiple queues
+-  VLAN filter
+
+Prerequisites
+-------------
+
+-  This code is tested with vfio-pci driver installed with Ubuntu 18.04
+   which has kernel version 4.15.0-33-generic.
+
+-  This code is tested with ESXi vSwitch version 6.0, release build
+   3620759.
+
+-  Driver requires MSI-X interrupt support, which is not supported by
+   uio_pci_generic driver, so vfio-pci needs to be used. On systems
+   without IOMMU vfio driver can still be used with recent kernels which
+   support no-iommu mode.
+
+System setup
+~~~~~~~~~~~~
+
+To use the native VPP vmxnet3 driver use the following Steps
+
+Load VFIO driver
+
+.. code-block:: console
+
+    $ sudo modprobe vfio-pci
+
+For systems without IOMMU only, enable unsafe NOIOMMU mode
+
+.. code-block:: console
+
+    $ echo Y | sudo tee /sys/module/vfio/parameters/enable_unsafe_noiommu_mode
+
+To bind interface to vfio-pci first install the :ref:`configutil`. This will download
+the dpdk_devbind.py script. It is located in */usr/vpp/vpp-config/scripts* with Centos
+and */usr/local/vpp/vpp-config/scripts* with Ubuntu. 
+
+Bind the driver with the following commands:
+
+.. code-block:: console
+
+    $ sudo /usr/local/vpp/vpp-config/scripts/dpdk-devbind.py -s
+
+    Network devices using DPDK-compatible driver
+    ============================================
+    <none>
+    
+    Network devices using kernel driver
+    ===================================
+    0000:03:00.0 'VMXNET3 Ethernet Controller' if=ens160 drv=vmxnet3 unused=vfio-pci,uio_pci_generic 
+    0000:0b:00.0 'VMXNET3 Ethernet Controller' drv=vfio-pci unused=vmxnet3,uio_pci_generic
+    0000:13:00.0 'VMXNET3 Ethernet Controller' drv=vfio-pci unused=vmxnet3,uio_pci_generic
+    .....
+
+    $ sudo /usr/local/vpp/vpp-config/scripts/dpdk-devbind.py --bind vfio-pci 0b:00.0
+
+
+Interface Creation
+~~~~~~~~~~~~~~~~~~
+
+Now create the interface dynamically with following:
+
+.. code-block:: console
+
+    $ sudo vppctl create interface vmxnet3 0000:0b:00.0
+    $ sudo set int state vmxnet3-0/b/0/0 up
+
+Interface Deletion
+~~~~~~~~~~~~~~~~~~
+
+If the interface needs to be deleted:
+
+.. code-block:: console
+
+    $ sudo delete interface vmxnet3 <if-name>
+
+Show vmxnet3
+~~~~~~~~~~~~
+
+Interface and ring information can be obtained with the command
+**show vmxnet3 [if-name] [desc]**
+
+For example:
+
+.. code-block:: console
+
+    $ sudo vppctl show vmxnet
+    Interface: vmxnet3-0/b/0/0 (ifindex 1)
+      Version: 1
+      PCI Address: 0000:0b:00.0
+      Mac Address: 00:50:56:88:63:be
+      hw if index: 1
+      Device instance: 0
+      Number of interrupts: 2
+      Queue 0 (RX)
+        RX completion next index 786
+        RX completion generation flag 0x80000000
+        ring 0 size 4096 fill 4094 consume 785 produce 784
+        ring 1 size 4096 fill 4096 consume 0 produce 0
+      Queue 0 (TX)
+        TX completion next index 216
+        TX completion generation flag 0x0
+        size 4096 consume 216 produce 245