[PATCH] mxs/dma: Enlarge the CCW descriptor area to 4 pages

Marek Vasut marex at denx.de
Tue Sep 4 22:57:54 EDT 2012

Dear Shawn Guo,

> On Wed, Sep 05, 2012 at 03:46:39AM +0200, Marek Vasut wrote:
> > Let me ask about another thing. If there'll eventually be some device
> > that'd need even larger transfer (say ... hundreds of megs) we'd end up
> > with trouble again.
> > 
> > One way to fix this is to recycle descriptors that were already used
> > during the transfer, but can we really do it fast enough, so the DMA
> > would do it's job at one end of the descriptor chain and we'd be
> > building the other?
> It looks like a solution, but I'm not sure if it works either.

Besides ... if the system is under some heavier load, this might crash too.

Best regards,
Marek Vasut

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