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diff --git a/doc/guides/nics/ena.rst b/doc/guides/nics/ena.rst new file mode 100644 index 00000000..9f938486 --- /dev/null +++ b/doc/guides/nics/ena.rst @@ -0,0 +1,251 @@ +.. 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> |