[PATCH 2/8] dmaengine: mv_xor: add support for a38x command in descriptor mode

Arnd Bergmann arnd at arndb.de
Wed May 13 01:46:45 PDT 2015

On Wednesday 13 May 2015 10:15:35 Maxime Ripard wrote:
> > Alternatively, you could leave the XOR_DESCRIPTOR_SWAP flag disabled
> > and just swap the descriptors manually like a lot of other drivers
> > do. You have to swap the mmio accesses anywya.
> That won't be easily doable however.
> Not only the endianness of the individual fields in the descriptor
> changes, but changing the endianness also swaps the fields themselves
> by pair of u32.
> You can see that here:
> http://lxr.free-electrons.com/source/drivers/dma/mv_xor.h#L159
> So I'm guessing that leaving it like it is was the more readable
> solution.

I see, yes that would get a bit ugly.


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