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DMA transfer query

Hi,

I am trying to use DMA transfer in my video phone application to transfer MJPEG encoded data from camera buffer to MJPEG decoder buffer. I am trying DMA transfer because memcpt() takes lots of CPU time. I am trying to do 1D to 1D transfer. The source and destination physical addresses are proper.

I am configuring edma_params structure as follows:

edmaparams.srcmode = 0;

edmaparams.srcfifowidth = 0;

edmaparams.srcbidx = 0;

edmaparams.srccidx = 0;

edmaparams.dstmode = 0;

edmaparams.dstfifowidth = 0;

edmaparams.dstbidx = 0;

edmaparams.dstcidx = 0;

edmaparams.src = src_ptr;

edmaparams.dst = dst_ptr;

edmaparams.acnt = u32BytesToTransfer; // Total bytes to be transferred 

edmaparams.bcnt = 1;

edmaparams.ccnt = 1;

edmaparams.bcntrld = 0;

edmaparams.syncmode = 1;  // AB-sync

After this I have used 'DM365MMAP_IOCMEMCPY' ioctl to do the dma transfer.

The data is not getting copied properly. 

Can we use DMA transfer like this? 

Please suggest the parameter configurations.

Thanks and Regards,

Avneet