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imx6 SDMA and EIM bus

Question asked by Andreas Orfanos on May 28, 2014
Latest reply on Jul 30, 2018 by yunteng long

I would like to use external events on the pins event0, and event1 to trigger SDMA requests to send data to the external EIM bus.

I am using IMX_DMATYPE_EXT for configuring the dma, and I use event1 as an external trigger. I have observed that

the events are handled by the DMA, and empties the buffer, but I don't see anything on the EIM bus.

I have started having the impression that the IMX_DMATYPE_EXT is using ROM scripts that do not put data to the EIM bus.


    case IMX_DMATYPE_EXT:
        per_2_emi = sdma->script_addrs->app_2_mcu_addr;
        emi_2_per = sdma->script_addrs->mcu_2_app_addr;
        break;

 

And as far I can see from the imx6 manual:

 

mcu_2_app
This generic script is used to transfer data from memories accessed by the BurstDMA
(External memories), to a 8, 16, 24 or 32-bit peripheral connected to the AIPS accessed
through the Periphera DMA of SDMA.

 

Have you ever had external SDMA events to trigger transfers to EIM bus? It should be possible, right?

 

Kind regards,

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