How to get P2020 DMA over PCIe to transmit more than one data byte per packet?

[toddreed]

We have adjusted the BWC (Bandwidth/pause control bits of DMA mode register), but haven't seen any change.  We always get one data byte.  Thank you.

Todd

[LPP · Accepted solution]

Please check the value of DMAx_MRn[DAHE,SAHE] (RM Section 13.3.1).

Probably, you are trying to DMA data to FPGA register on the PCIe side of DMA. DMA doesn't burst if DAHE,SAHE != 0.

The source/destination transaction size calculations provided in RM Section 13.4.1.1 is only applicable to the case of DAHE,SAHE = 0.

Have a great day,
Pavel

-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------