AVB Support on i.MX 8M Plus - Preferred MAC

[praveen_yaramada]

Hello NXP Support,

Of the two MACs in this SOC (iMX 8M Plus), which one is preferred for AVB? Are there any qualitative or compatibility and certification benefits of one over the other?

Two MACs being:

1. ENET (driven by fec) and
2. ENET_QOS(dwmac-eqos).

I reviewed the features of both MACs in the manual "IMX8MP_RM (rev 2, Feb 2024)", it highlighted the AVB on ENET_QOS for advanced use. This contrasts with the reference software exemplified by GenAVB_TSN. In the linux-imx-rtedge distrubution, this software stack appears to use the ENET (probed by fec driver). Additionally it is leveraging the enhancements to fec driver (specifically, CONFIG_AVB_SUPPORT) which is not in the linux-imx.

Meanwhile, this older KB article seems to be using ENET_QOS. I have yet to try this, but a quick read shows it is based on linux-imx but not using the GenAVB_TSN.

I am leaning towards a combination - ENET_QOS with GenAVB_TSN. It is not evident whether this combination is supported. Please advise if any technical limitations. Is there a path for getting GenAVB_TSN operate on ENET_QOS with the drivers of linux-imx?

Any insights or recommendations would be greatly appreciated.

Thank you!

[jimmychan]

For your reference.

https://github.com/NXP/GenAVB_TSN

https://github.com/NXP/GenAVB_TSN/releases/tag/6_1_0

[praveen_yaramada]

Hello @jimmychan,

Could you please clarify if the combination of "GenAVB_TSN + ENET_QOS" is supported on the i.MX8M Plus? The documentation is unclear on this.

If it's not supported, could you explain whether this is due to technical limitations of the ENET_QOS MAC? I prefer ENET_QOS because of the pinmux configuration on ENET.

Thank you for your assistance.

[jimmychan]

FYI. Please refer to chapter 5.2 in the document below.

https://www.nxp.com.cn/docs/en/user-guide/REALTIMEEDGEUG.pdf

The setup is connected to i.MX8MP TSN interface (EQOS).

[praveen_yaramada]

Hello @jimmychan,

It appears the chapter 5.2 in the REALTIMEEDGEUG focuses on the TSN endpoint. However, I am interested in the AVB endpoint, for which I am referring this document (GENAVBTSNUG)[https://www.nxp.com/docs/en/user-guide/GENAVBTSNUG.pdf]

I couldn't find any definitive information on whether the AVB-endpoint is supported on the ENET_QOS as far as the GenAVB stack is concerned.

Could you please clarify, specifically whether the GenAVB stack for AVB endpoint is supported with ENET_QOS.

Thank you for your support.

[jimmychan · Accepted solution]

Sorry, I got the reply from the AE team. Currently the AVB Endpoint configuration for MPU is only supported on the FEC interface.