[dpdk-dev,v4,10/10] doc: add rawdev library page and support Doxygen
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Commit Message
Signed-off-by: Shreyansh Jain <shreyansh.jain@nxp.com>
---
MAINTAINERS | 1 +
doc/api/doxy-api-index.md | 1 +
doc/api/doxy-api.conf | 1 +
doc/guides/prog_guide/index.rst | 1 +
doc/guides/prog_guide/rawdev_lib.rst | 107 +++++++++++++++++++++++++++++++++
doc/guides/rel_notes/release_18_02.rst | 12 ++++
6 files changed, 123 insertions(+)
create mode 100644 doc/guides/prog_guide/rawdev_lib.rst
@@ -321,6 +321,7 @@ M: Hemant Agrawal <hemant.agrawal@nxp.com>
F: lib/librte_rawdev/*
F: drivers/rawdev/skeleton/*
F: test/test/test_rawdev.c
+F: doc/guides/prog_guide/rawdev_lib.rst
Bus Drivers
@@ -43,6 +43,7 @@ The public API headers are grouped by topics:
[rte_tm] (@ref rte_tm.h),
[rte_mtr] (@ref rte_mtr.h),
[bbdev] (@ref rte_bbdev.h),
+ [rawdev] (@ref rte_rawdev.h),
[cryptodev] (@ref rte_cryptodev.h),
[security] (@ref rte_security.h),
[eventdev] (@ref rte_eventdev.h),
@@ -71,6 +71,7 @@ INPUT = doc/api/doxy-api-index.md \
lib/librte_pipeline \
lib/librte_port \
lib/librte_power \
+ lib/librte_rawdev \
lib/librte_reorder \
lib/librte_ring \
lib/librte_sched \
@@ -75,6 +75,7 @@ Programmer's Guide
vhost_lib
metrics_lib
port_hotplug_framework
+ rawdev_lib
source_org
dev_kit_build_system
dev_kit_root_make_help
new file mode 100644
@@ -0,0 +1,107 @@
+.. 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)
@@ -192,6 +192,17 @@ New Features
is unaffected by these changes, and can continue to be used for this
and subsequent releases until such time as it's deprecation is announced.
+* **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_lib` programmer's guide for more details.
API Changes
-----------
@@ -308,6 +319,7 @@ The libraries prepended with a plus sign were incremented in this version.
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