[dpdk-dev] [PATCH v4 1/4] ena: Amazon ENA documentation

[Jan Medala <jan@semihalf.com>]

Signed-off-by: Evgeny Schemeilin <evgenys@amazon.com>
Signed-off-by: Alexander Matushevsky <matua@amazon.com>
Signed-off-by: Jan Medala <jan@semihalf.com>
Signed-off-by: Jakub Palider <jpa@semihalf.com>
---
 MAINTAINERS               |   8 ++
 doc/guides/nics/ena.rst   | 252 ++++++++++++++++++++++++++++++++++++++++++++++
 doc/guides/nics/index.rst |   1 +
 3 files changed, 261 insertions(+)
 create mode 100644 doc/guides/nics/ena.rst

diff --git a/MAINTAINERS b/MAINTAINERS
index 628bc05..d6a726d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -261,6 +261,14 @@ Linux AF_PACKET
 M: John W. Linville <linville@tuxdriver.com>
 F: drivers/net/af_packet/
 
+Amazon ena
+M: Jan Medala <jan@semihalf.com>
+M: Jakub Palider <jpa@semihalf.com>
+M: Netanel Belgazal <netanel@amazon.com>
+M: Evgeny Schemeilin <evgenys@amazon.com>
+F: drivers/net/ena/
+F: doc/guides/nics/ena.rst
+
 Chelsio cxgbe
 M: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
 F: drivers/net/cxgbe/
diff --git a/doc/guides/nics/ena.rst b/doc/guides/nics/ena.rst
new file mode 100644
index 0000000..11bd922
--- /dev/null
+++ b/doc/guides/nics/ena.rst
@@ -0,0 +1,252 @@
+.. BSD LICENSE
+
+    Copyright (c) 2015-2016 Amazon.com, Inc. or its affiliates.
+    All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+
+    * Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+    * Neither the name of Amazon.com, Inc. nor the names of its
+    contributors may be used to endorse or promote products derived
+    from this software without specific prior written permission.
+
+    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ENA Poll Mode Driver
+====================
+
+The ENA PMD is a DPDK poll-mode driver for the Amazon Elastic
+Network Adapter (ENA) family.
+
+Overview
+--------
+
+The ENA driver exposes a lightweight management interface with a
+minimal set of memory mapped registers and an extendable command set
+through an Admin Queue.
+
+The driver supports a wide range of ENA adapters, is link-speed
+independent (i.e., the same driver is used for 10GbE, 25GbE, 40GbE,
+etc.), and it negotiates and supports an extendable feature set.
+
+ENA adapters allow high speed and low overhead Ethernet traffic
+processing by providing a dedicated Tx/Rx queue pair per CPU core.
+
+The ENA driver supports industry standard TCP/IP offload features such
+as checksum offload and TCP transmit segmentation offload (TSO).
+
+Receive-side scaling (RSS) is supported for multi-core scaling.
+
+Some of the ENA devices support a working mode called Low-latency
+Queue (LLQ), which saves several more microseconds.
+
+Management Interface
+--------------------
+
+ENA management interface is exposed by means of:
+
+* Device Registers
+* Admin Queue (AQ) and Admin Completion Queue (ACQ)
+
+ENA device memory-mapped PCIe space for registers (MMIO registers)
+are accessed only during driver initialization and are not involved
+in further normal device operation.
+
+AQ is used for submitting management commands, and the
+results/responses are reported asynchronously through ACQ.
+
+ENA introduces a very small set of management commands with room for
+vendor-specific extensions. Most of the management operations are
+framed in a generic Get/Set feature command.
+
+The following admin queue commands are supported:
+
+* Create I/O submission queue
+* Create I/O completion queue
+* Destroy I/O submission queue
+* Destroy I/O completion queue
+* Get feature
+* Set feature
+* Get statistics
+
+Refer to ``ena_admin_defs.h`` for the list of supported Get/Set Feature
+properties.
+
+Data Path Interface
+-------------------
+
+I/O operations are based on Tx and Rx Submission Queues (Tx SQ and Rx
+SQ correspondingly). Each SQ has a completion queue (CQ) associated
+with it.
+
+The SQs and CQs are implemented as descriptor rings in contiguous
+physical memory.
+
+Refer to ``ena_eth_io_defs.h`` for the detailed structure of the descriptor
+
+The driver supports multi-queue for both Tx and Rx.
+
+Configuration information
+-------------------------
+
+**DPDK Configuration Parameters**
+
+  The following configuration options are available for the ENA PMD:
+
+   * **CONFIG_RTE_LIBRTE_ENA_PMD** (default y): Enables or disables inclusion
+     of the ENA PMD driver in the DPDK compilation.
+
+
+   * **CONFIG_RTE_LIBRTE_ENA_DEBUG_INIT** (default y): Enables or disables debug
+     logging of device initialization within the ENA PMD driver.
+
+   * **CONFIG_RTE_LIBRTE_ENA_DEBUG_RX** (default n): Enables or disables debug
+     logging of RX logic within the ENA PMD driver.
+
+   * **CONFIG_RTE_LIBRTE_ENA_DEBUG_TX** (default n): Enables or disables debug
+     logging of TX logic within the ENA PMD driver.
+
+   * **CONFIG_RTE_LIBRTE_ENA_COM_DEBUG** (default n): Enables or disables debug
+     logging of low level tx/rx logic in ena_com(base) within the ENA PMD driver.
+
+**ENA Configuration Parameters**
+
+   * **Number of Queues**
+
+     This is the requested number of queues upon initialization, however, the actual
+     number of receive and transmit queues to be created will be the minimum between
+     the maximal number supported by the device and number of queues requested.
+
+   * **Size of Queues**
+
+     This is the requested size of receive/transmit queues, while the actual size
+     will be the minimum between the requested size and the maximal receive/transmit
+     supported by the device.
+
+Building DPDK
+-------------
+
+See the :ref:`DPDK Getting Started Guide for Linux <linux_gsg>` for
+instructions on how to build DPDK.
+
+By default the ENA PMD library will be built into the DPDK library.
+
+For configuring and using UIO and VFIO frameworks, please also refer :ref:`the
+documentation that comes with DPDK suite <linux_gsg>`.
+
+Supported ENA adapters
+----------------------
+
+Current ENA PMD supports the following ENA adapters including:
+
+* ``1d0f:ec20`` - ENA VF
+* ``1d0f:ec21`` - ENA VF with LLQ support
+
+Supported Operating Systems
+---------------------------
+
+Any Linux distribution fulfilling the conditions described in ``System Requirements``
+section of :ref:`the DPDK documentation <linux_gsg>` or refer to *DPDK Release Notes*.
+
+Supported features
+------------------
+
+* Jumbo frames up to 9K
+* Port Hardware Statistics
+* IPv4/TCP/UDP checksum offload
+* TSO offload
+* Multiple receive and transmit queues
+* RSS
+* Low Latency Queue for Tx
+
+Unsupported features
+--------------------
+
+The features supported by the device and not yet supported by this PMD include:
+
+* Asynchronous Event Notification Queue (AENQ)
+
+Prerequisites
+-------------
+
+#. Prepare the system as recommended by DPDK suite.  This includes environment
+   variables, hugepages configuration, tool-chains and configuration
+
+#. Insert igb_uio kernel module using the command 'modprobe igb_uio'
+
+#. Bind the intended ENA device to igb_uio module
+
+
+At this point the system should be ready to run DPDK applications. Once the
+application runs to completion, the ENA can be detached from igb_uio if necessary.
+
+Usage example
+-------------
+
+This section demonstrates how to launch **testpmd** with Amazon ENA
+devices managed by librte_pmd_ena.
+
+#. Load the kernel modules:
+
+   .. code-block:: console
+
+      modprobe uio
+      insmod ./x86_64-native-linuxapp-gcc/kmod/igb_uio.ko
+
+   .. note::
+
+      Currently Amazon ENA PMD driver depends on igb_uio user space I/O kernel module
+
+#. Mount and request huge pages:
+
+   .. code-block:: console
+
+      mount -t hugetlbfs nodev /mnt/hugepages
+      echo 1024 > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
+
+#. Bind UIO driver to ENA device (using provided by DPDK binding tool):
+
+   .. code-block:: console
+
+      ./tools/dpdk_nic_bind.py --bind=igb_uio 0000:02:00.1
+
+#. Start testpmd with basic parameters:
+
+   .. code-block:: console
+
+      ./x86_64-native-linuxapp-gcc/app/testpmd -c 0xf -n 4 -- -i
+
+   Example output:
+
+   .. code-block:: console
+
+      [...]
+      EAL: PCI device 0000:02:00.1 on NUMA socket -1
+      EAL:   probe driver: 1d0f:ec20 rte_ena_pmd
+      EAL:   PCI memory mapped at 0x7f9b6c400000
+      PMD: eth_ena_dev_init(): Initializing 0:2:0.1
+      Interactive-mode selected
+      Configuring Port 0 (socket 0)
+      Port 0: 00:00:00:11:00:01
+      Checking link statuses...
+      Port 0 Link Up - speed 10000 Mbps - full-duplex
+      Done
+      testpmd>
+
diff --git a/doc/guides/nics/index.rst b/doc/guides/nics/index.rst
index 8618114..694b95b 100644
--- a/doc/guides/nics/index.rst
+++ b/doc/guides/nics/index.rst
@@ -39,6 +39,7 @@ Network Interface Controller Drivers
     bnx2x
     cxgbe
     e1000em
+    ena
     enic
     fm10k
     ixgbe
-- 
1.9.1