T2080 Processor with AMD GPU

[KarthikSSK16]

Hi Team, 

We are currently planing to use T2080 processor and connect to discrete GPU via PCIe , we understand from our industry partner that there will be a performance hit if we use this architecture since there is a byte swap issue and all the swaping to be done on the GPU software which will degrade the performance.

We would like to understand if this issue persist or is there any mechanism in T2080 processor to change the byte swap and communicate with the GPU?

Regards,
KS

[yipingwang]

The T2080 PCIe controller does not provide any hardware mechanism for byte swapping on inbound or outbound PCIe transactions. However, this does not introduce any inherent performance penalty related to endianness.
Large GPU data buffers are always treated as raw byte streams. Neither the CPU nor the GPU performs any byte swapping on these buffers. Only a very small amount of control metadata (such as descriptors and status fields) requires endian conversion, and this is handled efficiently by the GPU driver running on the CPU side. The overhead is negligible.
Therefore, the GPU data path remains efficient, and no additional GPU‑side processing is required.

[KarthikSSK16]

Hi Team,

Thanks for your reply, but we understand from the GPU industry partner that there is a byte swap issue since T2 is big endian and the GPU(AMD E9171) is little endian and all the transaction byte swap has to be done which will severely impact the performance and drop the GPU performance. 

What might be the issue here could you please provide some details.

Regards,

Karthik