Forced EDMA Link Updates

Hi,

Thanks for your post.

It would made you to think forced EDMA link update scenario only if your link update fails in your case. I would suggest you to insert a second dummy transfer of 0 bytes which is legal would fix your issue and will link correctly to the LINK field address when the dummy transfer is executed.

Usually, When the EDMA submits the transfer request (TR) for the PaRAM, it uses the link PaRAM contents present at the time the TR is submitted. For the single PaRAM case, the PaRAM is "empty" at the time of transfer request so no linking takes place (it gets written when the TR is complete, but it is too late by that time).  In your case, you have taken care in setting a timeout event in which EDMA wouldn't stuck in waiting for sync event in case, if it receives lesser data than the programmed data length, so the original write to the desired destination would have happened from the first transfer and proper link update would happen when second dummy transfer would be executed, thus it wouldn't have necessity to force a link update on the first transfer which would let link update happen naturally on the second dummy transfer.

Maybe, you can configure the dummy PaRAM set are as follows:

prm->opt = 0x82418000;

prm->srcAddr = NULL;

prm->destAddr = NULL;

prm->aCnt       = 1;

prm->bCnt       = 0;

prm->cCnt       = 0;

prm->bCntReload = 0;

prm->srcBIdx    = 0;

prm->destBIdx   = 0;

prm->srcCIdx    = 0;

prm->destCIdx   = 0;

prm->linkAddr   = 0xXXXX; (configure accordingly for your case)

Thanks & regards,

Sivaraj K

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

Please click the Verify Answer button on this post if it answers your question

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