octeon_ep: Add driver framework and device initialization

Add driver framework and device setup and initialization for Octeon
PCI Endpoint NIC.

Add implementation to load module, initilaize, register network device,
cleanup and unload module.

Signed-off-by: Veerasenareddy Burru <vburru@marvell.com>
Signed-off-by: Abhijit Ayarekar <aayarekar@marvell.com>
Signed-off-by: Satananda Burla <sburla@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/device_drivers/ethernet/index.rst

@@ -39,6 +39,7 @@ Contents:
    intel/iavf
    intel/ice
    marvell/octeontx2
+   marvell/octeon_ep
    mellanox/mlx5
    microsoft/netvsc
    neterion/s2io

Documentation/networking/device_drivers/ethernet/marvell/octeon_ep.rst

@@ -0,0 +1,35 @@
+.. SPDX-License-Identifier: GPL-2.0+
+
+====================================================================
+Linux kernel networking driver for Marvell's Octeon PCI Endpoint NIC
+====================================================================
+
+Network driver for Marvell's Octeon PCI EndPoint NIC.
+Copyright (c) 2020 Marvell International Ltd.
+
+Contents
+========
+
+- `Overview`_
+- `Supported Devices`_
+- `Interface Control`_
+
+Overview
+========
+This driver implements networking functionality of Marvell's Octeon PCI
+EndPoint NIC.
+
+Supported Devices
+=================
+Currently, this driver support following devices:
+ * Network controller: Cavium, Inc. Device b200
+
+Interface Control
+=================
+Network Interface control like changing mtu, link speed, link down/up are
+done by writing command to mailbox command queue, a mailbox interface
+implemented through a reserved region in BAR4.
+This driver writes the commands into the mailbox and the firmware on the
+Octeon device processes them. The firmware also sends unsolicited notifications
+to driver for events suchs as link change, through notification queue
+implemented as part of mailbox interface.