Romain Gallais

LS1046A DMA performances

Discussion created by Romain Gallais on Apr 18, 2019
Latest reply on Jul 14, 2019 by Yiping Wang

Hi everyone,


I would like to discuss about the LS1046A DMA performances and my issues.

Indeed, I have some troubles with the DMA performances achieved by my platform with a LS1046A SoC.

I would like to achieve high throughput for PCIe transfers with the use of DMA engines provided by the SoC.


By using QDMA with DPAA1:

I can't transfer above 25 MB/s with qDMA when writting to a PCIe area and 40 kB/s when reading to a PCIe area.

From the "Layerscape Software Development Kit User Guide", performances looks similar except readings (from dmatest).

I tried using eDMA, but I failed to make it work. I may have misconfigured my transfer but I didn't find any relevant example to use it correctly..

Am I missing something ? Are there some guidelines or examples to use those drivers in a better way ?

Has someone any experiences in this case ?

I am using the linux kernel 4.19 from LSDK19.03.

Thank you for your time !