SDMA transfer to/from memory shared with PCIe root

[FredrikMoller]

I have an imx6 set up as PCIe endpoint where the lower 16MB of DDR memory (address 0x10000000-0x11000000) is shared with the PCIe root on the other side of the PCIe link.

I want to use SDMA on the imx6 to copy to/from this memory. Is this possible?

The reason I ask is because of this discussion PCIe DMA problems with i.MX6 which seems to imply that that is not the case.

[igorpadykov · Accepted solution]

Hi Frederik

yes correct, SDMA can not be used with PCIe module.

Also it may be useful to look at

i.MX6Q PCIe EP/RC Validation System

Best regards

igor

-----------------------------------------------------------------------------------------------------------------------

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

-----------------------------------------------------------------------------------------------------------------------

[FredrikMoller]

Thanks a lot!

Btw, you don't happen to know where this limitation is documented in the reference manual for imx6?

Regards,

Fredrik

[igorpadykov]

There are no direct references, however

for example there is no PCIe in

Table A-1. SDMA Scripts Overview IMX6DQRM

~igor