topic Using eDMA for VPU en/decoding in i.MX Processors

Using eDMA for VPU en/decoding

crg7475 — Mon, 06 Mar 2023 17:44:49 GMT

Is it possible to use the eDMA for VPU en/decoding, specifically for transferring raw frames from/to the VPU? From what I see, the eDMA can do scatter-gather operations. This means it could in theory use virtual memory blocks (as long as they are located in the physical RAM and not paged to disk), because even if these are discontinuous in physical memory, the scatter-gather operation could read from the fragments. The big advantage would be that it would not be depending on the CMA, which is prone to fragmentation problems. But from what I recall, the eDMA is limited to some modules?

Re: Using eDMA for VPU en/decoding

Bio_TICFSL — Tue, 07 Mar 2023 16:18:02 GMT

Hello,

As far as i Know, the VPU of i.MX8 ha eDMA working for encode/ Decode.

Regards

Re: Using eDMA for VPU en/decoding

crg7475 — Tue, 07 Mar 2023 16:20:07 GMT

But then, is it set up to allow for scatter/gather operation? Could the VPU be set up to use system memory (which is fully resident in RAM) instead of having to allocate physically contiguous memory through CMA?