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Date: Tue, 6 Jun 2006 11:55:48 -0700
From: Naru Sundar <nsundar@fulcrummicro.com>
To: Liu Dave-r63238 <DaveLiu@freescale.com>
Subject: Re: ppc85xx DMA
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On Tue, Jun 06, 2006 at 09:39:29AM +0800, Liu Dave-r63238 wrote:
> What is the DMA transfer mode? Is direct or chaining mode?

Direct mode.  I fixed an error with my bit ordering for the configuration
registers, and now the transfer seems to complete, but I don't see any
actual data showing up in the destination register that I am writing to.

> Did you ioremap the DMA register space?

Yes, I can write the destination address manually.  So I am thinking my addresses
are wrong.

For the source and dest address I used:

dma_map_single(NULL, ptr, len, DMA_TO_DEVICE)

(which effectively does a virt_to_bus on ppc and so should just return to me
the bus address used by the dma).

-naru