--- /dev/null
+.. SPDX-License-Identifier: BSD-3-Clause
+ Copyright 2018 NXP
+
+Rawdevice Library
+=================
+
+Introduction
+------------
+
+In terms of device flavor (type) support, DPDK currently has ethernet
+(lib_ether), cryptodev (libcryptodev), eventdev (libeventdev) and vdev
+(virtual device) support.
+
+For a new type of device, for example an accelerator, there are not many
+options except:
+1. create another lib/librte_MySpecialDev, driver/MySpecialDrv and use it
+through Bus/PMD model.
+2. Or, create a vdev and implement necessary custom APIs which are directly
+exposed from driver layer. However this may still require changes in bus code
+in DPDK.
+
+The DPDK Rawdev library is an abstraction that provides the DPDK framework a
+way to manage such devices in a generic manner without expecting changes to
+library or EAL for each device type. This library provides a generic set of
+operations and APIs for framework and Applications to use, respectively, for
+interfacing with such type of devices.
+
+Design
+------
+
+Key factors guiding design of the Rawdevice library:
+
+1. Following are some generic operations which can be treated as applicable
+ to a large subset of device types. None of the operations are mandatory to
+ be implemented by a driver. Application should also be design for proper
+ handling for unsupported APIs.
+
+ * Device Start/Stop - In some cases, 'reset' might also be required which
+ has different semantics than a start-stop-start cycle.
+ * Configuration - Device, Queue or any other sub-system configuration
+ * I/O - Sending a series of buffers which can enclose any arbitrary data
+ * Statistics - Fetch arbitrary device statistics
+ * Firmware Management - Firmware load/unload/status
+
+2. Application API should be able to pass along arbitrary state information
+ to/fro device driver. This can be achieved by maintaining context
+ information through opaque data or pointers.
+
+Figure below outlines the layout of the rawdevice library and device vis-a-vis
+other well known device types like eth and crypto:
+
+.. code-block:: console
+
+ +-----------------------------------------------------------+
+ | Application(s) |
+ +------------------------------.----------------------------+
+ |
+ |
+ +------------------------------'----------------------------+
+ | DPDK Framework (APIs) |
+ +--------------|----|-----------------|---------------------+
+ / \ \
+ (crypto ops) (eth ops) (rawdev ops) +----+
+ / \ \ |DrvA|
+ +-----'---+ +----`----+ +---'-----+ +----+
+ | crypto | | ethdev | | raw |
+ +--/------+ +---/-----+ +----/----+ +----+
+ /\ __/\ / ..........|DrvB|
+ / \ / \ / ../ \ +----+
+ +====+ +====+ +====+ +====+ +==/=+ ```Bus Probe
+ |DevA| |DevB| |DevC| |DevD| |DevF|
+ +====+ +====+ +====+ +====+ +====+
+ | | | | |
+ ``|``````|````````|``````|`````````````````|````````Bus Scan
+ (PCI) | (PCI) (PCI) (PCI)
+ (BusA)
+
+ * It is assumed above that DrvB is a PCI type driver which registers itself
+ with PCI Bus
+ * Thereafter, when the PCI scan is done, during probe DrvB would match the
+ rawdev DevF ID and take control of device
+ * Applications can then continue using the device through rawdev API
+ interfaces
+
+
+Device Identification
+~~~~~~~~~~~~~~~~~~~~~
+
+Physical rawdev devices are discovered during the Bus scan executed at DPDK
+initialization, based on their identification and probing with corresponding
+driver. Thus, a generic device needs to have an identifier and a driver
+capable of identifying it through this identifier.
+
+Virtual devices can be created by two mechanisms, either using the EAL command
+line options or from within the application using an EAL API directly.
+
+From the command line using the --vdev EAL option
+
+.. code-block:: console
+
+ --vdev 'rawdev_dev1'
+
+Our using the rte_vdev_init API within the application code.
+
+.. code-block:: c
+
+ rte_vdev_init("rawdev_dev1", NULL)
renamed the application from SW PMD specific ``eventdev_pipeline_sw_pmd``
to PMD agnostic ``eventdev_pipeline``.
+* **Added Rawdev, a generic device support library.**
+
+ Rawdev library provides support for integrating any generic device type with
+ DPDK framework. Generic devices are those which do not have a pre-defined
+ type within DPDK, for example, ethernet, crypto, event etc.
+ A set of northbound APIs have been defined which encompass a generic set of
+ operations by allowing applications to interact with device using opaque
+ structures/buffers. Also, southbound APIs provide APIs for integrating device
+ either as as part of a physical bus (PCI, FSLMC etc) or through ``vdev``.
+
+ See the :doc:`../prog_guide/rawdev` programmer's guide for more details.
+
* **Added new multi-process communication channel**
Added a generic channel in EAL for multi-process (primary/secondary) communication.
librte_pmd_vhost.so.2
librte_port.so.3
librte_power.so.1
+ librte_rawdev.so.1
librte_reorder.so.1
librte_ring.so.1
librte_sched.so.1
git.droids-corp.org / dpdk.git / commitdiff