xref: /dpdk/doc/guides/eventdevs/octeontx.rst (revision a912cb5bdd373b2db8052ee7f21a3216dfc144d0)
1..  SPDX-License-Identifier: BSD-3-Clause
2    Copyright(c) 2017 Cavium, Inc
3
4OCTEON TX SSOVF Eventdev Driver
5===============================
6
7The OCTEON TX SSOVF PMD (**librte_event_octeontx**) provides poll mode
8eventdev driver support for the inbuilt event device found in the **Cavium OCTEON TX**
9SoC family as well as their virtual functions (VF) in SR-IOV context.
10
11More information can be found at `Cavium, Inc Official Website
12<http://www.cavium.com/OCTEON-TX_ARM_Processors.html>`_.
13
14Features
15--------
16
17Features of the OCTEON TX SSOVF PMD are:
18
19- 64 Event queues
20- 32 Event ports
21- HW event scheduler
22- Supports 1M flows per event queue
23- Flow based event pipelining
24- Flow pinning support in flow based event pipelining
25- Queue based event pipelining
26- Supports ATOMIC, ORDERED, PARALLEL schedule types per flow
27- Event scheduling QoS based on event queue priority
28- Open system with configurable amount of outstanding events
29- HW accelerated dequeue timeout support to enable power management
30- SR-IOV VF
31- HW managed event timers support through TIMVF, with high precision and
32  time granularity of 1us.
33- Up to 64 event timer adapters.
34
35Supported OCTEON TX SoCs
36------------------------
37- CN83xx
38
39Prerequisites
40-------------
41
42See :doc:`../platform/octeontx` for setup information.
43
44
45Initialization
46--------------
47
48The OCTEON TX eventdev is exposed as a vdev device which consists of a set
49of SSO group and work-slot PCIe VF devices. On EAL initialization,
50SSO PCIe VF devices will be probed and then the vdev device can be created
51from the application code, or from the EAL command line based on
52the number of probed/bound SSO PCIe VF device to DPDK by
53
54* Invoking ``rte_vdev_init("event_octeontx")`` from the application
55
56* Using ``--vdev="event_octeontx"`` in the EAL options, which will call
57  rte_vdev_init() internally
58
59Example:
60
61.. code-block:: console
62
63    ./your_eventdev_application --vdev="event_octeontx"
64
65
66Enable TIMvf stats
67------------------
68TIMvf stats can be enabled by using this option, by default the stats are
69disabled.
70
71.. code-block:: console
72
73    --vdev="event_octeontx,timvf_stats=1"
74
75
76Limitations
77-----------
78
79Burst mode support
80~~~~~~~~~~~~~~~~~~
81
82Burst mode is not supported. Dequeue and Enqueue functions accepts only single
83event at a time.
84
85Rx adapter support
86~~~~~~~~~~~~~~~~~~
87
88When eth_octeontx is used as Rx adapter event schedule type
89``RTE_SCHED_TYPE_PARALLEL`` is not supported.
90
91Event timer adapter support
92~~~~~~~~~~~~~~~~~~~~~~~~~~~
93
94When timvf is used as Event timer adapter the clock source mapping is as
95follows:
96
97.. code-block:: console
98
99        RTE_EVENT_TIMER_ADAPTER_CPU_CLK  = TIM_CLK_SRC_SCLK
100        RTE_EVENT_TIMER_ADAPTER_EXT_CLK0 = TIM_CLK_SRC_GPIO
101        RTE_EVENT_TIMER_ADAPTER_EXT_CLK1 = TIM_CLK_SRC_GTI
102        RTE_EVENT_TIMER_ADAPTER_EXT_CLK2 = TIM_CLK_SRC_PTP
103
104When timvf is used as Event timer adapter event schedule type
105``RTE_SCHED_TYPE_PARALLEL`` is not supported.
106
107Max number of events
108~~~~~~~~~~~~~~~~~~~~
109
110Max number of events in OCTEON TX Eventdev (SSO) are only limited by DRAM size
111and they can be configured by passing limits to kernel bootargs as follows:
112
113.. code-block:: console
114
115        ssopf.max_events=4194304
116
117The same can be verified by looking at the following sysfs entry:
118
119.. code-block:: console
120
121        # cat /sys/module/ssopf/parameters/max_events
122        4194304
123
124The maximum number of events that can be added to SSO by the event adapters such
125as (Rx/Timer) should be limited to the above configured value.
126