Disable ICRC on Mellanox ConnectX-5 Ex (MT28800 Family)

Hi everyone!

For some experiments with a RoCE-v2 connection via the mentioned Mellanox-NIC (ConnectX-5 Ex, MT28800 Family), I would like to disable the ICRC-check on the card.
For doing so, I found this script on GitHub, which uses the “mstmcra” command to access the device registers 0x5361c.12:1, 0x5363c.12:1, 0x53614.29:1 and 0x53634.29:1 and set them all to 0x0. Apparently, this command doesn’t work as expected for me - the registers keep their initial value and ICRC is not switched off.

Does anyone have some experience with disableing ICRC on the ConnectX-5 Ex or know why my “mstmcra”-writes to the device registers would fail?

Thanks a lot in advance!

Hi Mheer99,

Thank you for posting your query on NVIDIA Community.

Based on your request, unfortunately there is no method of disabling iCRC validation with RoCE v2, as this is an InfiniBand and RoCE Specification requirement, which we do not have control over.

Thanks,
Namrata.