FW: FSL DMA engine transfer to PCI memory

David Laight David.Laight at ACULAB.COM
Wed Jan 26 02:02:12 EST 2011

> memcpy_toio() works fine, the data is written correctly. After
> DMA, the correct data appears at offsets 0xC, 0x1C, 0x2C, etc.
> of the destination buffer. I have 12 bytes of junk, 4 bytes of
> correct data, then again 12 bytes of junk and so on.

Does your Avalon MM slave decode the 4 byte enables?
The slave always sees 2 Avalon MM writes, one of which
will have no byte enables asserted.

(Actually it is a 64bit Avalon transfer - and a bus width adapter
gets inserted for you.)

Internal M9K memory blocks get this right...


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