DPAA offline port - use case

[PeterBergin]

I'm currently working on a design with ls1043a SoC that has a DPAA block. Looking in to DPAAs capabilities there is a feature in it called offline ports. I'm trying to read the current documentation but can not see the real use case for the offline ports. Can anyone give me some background and additional context here? Give me use case(s) for the offline ports in DPAA.

As far as I understand the documentation the offline ports in DPAA is a way for software to directly access FQs in QMAN. It is a way for software to send frames in to the queues that then take the normal route through FMAN with possibility to PCD and after that ends up in a new FQ. Got it correct?

Thanks,

/Peter

[yipingwang]

Hello Peter Bergin，

I uploaded QorIQ SDK 2.0 document in the following link.

https://drive.google.com/open?id=1IYiH_qNRZ18z5zk8P8-vYoTOovs01OLy 

Please refer to sections "7.6.1.1.6.1 MAC-less Over OH (Linux-USDPAA)", "7.6.1.1.6.2 MAC-less Over OH (Linux-Linux)", "9.9.2.4 Manipulating the reassembly_demo application" and "9.9.3.3 DPA IPSec".

Thanks,

Yiping

[PeterBergin]

Thanks for the pointer yipingwang‌! Just a follow up question to see if I understood the information correct:

For newer SDKs USDPAA is superseded with dpdk. Is it possible to let FMAN distribute certain traffic (for example based on protocol/port) to a FQ connected to an offline port  and let dpdk handle that traffic? And in parallel let all other traffic go to FQs handled by  normal port and the slow-path.

I'm looking for a way to split traffic on one Ethernet interface and do slow-path on some and fast-path on some. Is this possible with offline port or do you recommend another way?

Thanks,

/Peter

[yipingwang]

Hello Peter,

We do have support for VSP feature, where we can configure the traffic split between kernel and userspace on the basis of FMC file.

The DPDK code is available in LSDK 20.04, however the equivalent kernel patches could not make it to LSDK on time. You need to be applied separately to make it work.

Thanks,

Yiping

[PeterBergin]

Hi Yiping,

if not isolation is needed and in that case not VSP either, is the offline port a way to connect QMAN and user space? I mean is it possible to let dpdk take traffic from one FQ in QMAN and handle it?

Thanks,

/Peter

[yipingwang]

Hello /Peter,

You also could use FMan PCD on ethernet interface.

I attached a sample for your reference which has distribution and classification on IP address or port. Hope it can help you.

Thanks,

Yiping