Hi,
On Sun, Jul 31, 2011 at 7:57 PM, KyongHo Cho pullip.cho@samsung.com wrote:
On Fri, Jul 29, 2011 at 11:24 PM, Marek Szyprowski
...
Right now I have no idea how to handle this better. Perhaps with should be possible to specify somehow the target dma_address when doing memory allocation, but I'm not really convinced yet if this is really required.
What about using 'dma_handle' argument of alloc_coherent callback of dma_map_ops? Although it is an output argument, I think we can convey a hint or start address to map to the IO memory manager that resides behind dma API.
I also thought on this one, even dma_map_single receives a void *ptr which could be casted into a struct with both physical and virtual addresses to be mapped, but IMHO, this starts to add twists into the dma map parameters which might create confusion.
DMA API is so abstract that it cannot cover all requirements by various device drivers;;
Agree.
Regards,
Omar