SDMA >64 BD and cache/snooping?

[Zozobra]

I am doing a bare-metal i.MX6 quad.

Question 1:

The basic SDMA engine (scripts) only allows 64 buffer descriptors.  Can this be increased (new scripts)? 

Question 2:

Also, the example SDK shows that the buffer (not BD) memory must be non-cache.  Compared to the PowerQuiccII this seems like a drawback.  Does the SDMA engine allow snooping on the bus so that the buffer memory can be cached?

[igorpadykov]

Hi Zozobra

- right, this could be changed using new scripts

- unfortunately SDMA is not  capable to use cache

Best regards

igor

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[Zozobra]

Thanks, are there new scripts?  Is there starting source code and a compiler that we can use?

[igorpadykov]

nxp does not support sdma scripts developing.

Just for reference useful link:

http://billauer.co.il/blog/2011/10/imx-sdma-howto-memory-map/