There is an issue with VLAN tags not being inserted into packets generated by the PTP offload

[forfortuna]

I am using S32G399 and I am currently testing the PTP function based on GMAC0 based on M-7 core.

First, I have completed the offload setting by setting MAC_PTO_Control and confirmed that it sends and receives packets normally.

As the next step, we need to attach a VLAN tag to the PTP packets generated by PTP offload to apply TSN's TAS feature.

To do this

As a result of using functions such as [Gmac_Ip_SetTxOuterVlanTagForInsertion], [Gmac_Ip_SetTxInnerVlanTag], and DMA Queue setting, packets not generated by offload are transmitted with VLAN tags inserted, but packets automatically generated by offload are not transmitted with VLANs attached.

1. Is it not possible to insert a VLAN tag for packets generated by PTP Offload?

2. (Additional question) When using Offload, there is no function to update the time automatically like the PTP module on other boards?

[Daniel-Aguirre]

Hi,

We understand that currently, the whole description being provided is using the M7 core, is this correct?

If so, can help us providing the RTD version you are using? Also, any additional packages being used as well as versions for them. Were there any changes made to the packages/drivers being used?

Please, let us know.

[forfortuna]

Hi,

Thank you for your response.

The answer to your question is as follows

1. currently using M7 core
2. RTD version: (pic1) S32_RTD_4_0_2_D2306_ASR_REL_4_4_REV_0000_20230630
3. driver changes: I modified it like pic2 to take advantage of the PTP offload feature.

[Daniel-Aguirre · Accepted solution]

Hi,

Thanks for your feedback. As for overall PTP offload funtionality, we understand the following is provided:

"Software cannot enlarge the capability of PTP offload. Because once offload is enabled, the PTP messages will not reach the host cpu, and will be handled by the MAC layer. The software has no chance to intervene."

Which seems to be part of the limitations you are seeing.

Please, let us know.