[net-next,v10,8/8] docs: octeontx2: Add Documentation for QOS
Commit Message
Add QOS example configuration along with tc-htb commands
Signed-off-by: Hariprasad Kelam <hkelam@marvell.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
---
.../ethernet/marvell/octeontx2.rst | 45 +++++++++++++++++++
1 file changed, 45 insertions(+)
@@ -13,6 +13,7 @@ Contents
- `Drivers`_
- `Basic packet flow`_
- `Devlink health reporters`_
+- `Quality of service`_
Overview
========
@@ -287,3 +288,47 @@ For example::
NIX_AF_ERR:
NIX Error Interrupt Reg : 64
Rx on unmapped PF_FUNC
+
+
+Quality of service
+==================
+
+
+Hardware algorithms used in scheduling
+--------------------------------------
+
+octeontx2 silicon and CN10K transmit interface consists of five transmit levels
+starting from SMQ/MDQ, TL4 to TL1. Each packet will traverse MDQ, TL4 to TL1
+levels. Each level contains an array of queues to support scheduling and shaping.
+The hardware uses the below algorithms depending on the priority of scheduler queues.
+once the usercreates tc classes with different priorities, the driver configures
+schedulers allocated to the class with specified priority along with rate-limiting
+configuration.
+
+1. Strict Priority
+
+ - Once packets are submitted to MDQ, hardware picks all active MDQs having different priority
+ using strict priority.
+
+2. Round Robin
+
+ - Active MDQs having the same priority level are chosen using round robin.
+
+
+Setup HTB offload
+-----------------
+
+1. Enable HW TC offload on the interface::
+
+ # ethtool -K <interface> hw-tc-offload on
+
+2. Crate htb root::
+
+ # tc qdisc add dev <interface> clsact
+ # tc qdisc replace dev <interface> root handle 1: htb offload
+
+3. Create tc classes with different priorities::
+
+ # tc class add dev <interface> parent 1: classid 1:1 htb rate 10Gbit prio 1
+
+ # tc class add dev <interface> parent 1: classid 1:2 htb rate 10Gbit prio 7