SGDMA has corrupted read data in 8-bit operation

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I'm using the sgdma with 32-bit aligned read buffers as recommended but I still get corrupted read data. I haven't found any known issues about 8-bit operation. Does anyone know if 8-bit operation works? It seems to work for many transfers but not all as if the starting address affects it.

Thanks

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What interface are you transferring the data over?

I had terrible problems with holes in DMA'd data (from my dma engine) across the PCIe bus in Q 11.X with a memory mapped avalon interface.

Q12.0 fixed the problem (although the Q12.0 qsys component editor's badly broken so I'd recommend Q12.1 ).

Nial

GZoinker - Thanks for the suggestion. I was monitoring the read data directly (via SignalTap) going into the DMA so I know the data is bad from the start.

dsl - I think you may have got the answer! I'll check it out. Thanks!

Everyone gets caught out by the lack of cache coherency!

(except those of us who only use tightly coupled memory and no data caches)

Thanks dsl, clearing the cache has cleared things up!

Cheers

Greg