ppc85xx DMA
Naru Sundar
nsundar at fulcrummicro.com
Wed Jun 7 04:55:48 EST 2006
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
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