On Jun 30, 2005, at 10:12 AM, Clemens Koller wrote: > Hello! > > I am planning to use DMA/burst access for copying large chunks of data > (100MBytes) from the Local Bus (UPM accessed SRAM) to System Memory > (DDR) > as fast as possible (200MBytes/s). (As you can guess, that's a > framegrabber). > > As far as I have seen, the DMA engines of the MPC85xx (fsl-dma) are > not > supported in the classical way (dma_request(), free_dma()) in the > kernel 2.6.x. > The memory allocators in arch/ppc/dma-mapping.c seem to be usable, > but there is no valuable dma support yet (true?). > > I can program the DMA Controllers in my MPC8540 on my own to > achieve what I want > but it would be great to get/produce/stick with as much cross- > platform reusable > code as possible. > > Is there any ongoing work to put DMA support for the mpc85xx and > similar > devices into the kernel? Is there any ongoing work in this area > or is somebody working with the fsl-dma and can publish some code and > share some ideas?
I'm not aware of anyone work on such a thing. I'd be more than happy to accept patches for it. I know several of us have written some APIs on top of the DMA for 85xx. Those however are non-standard APIs. What APIs exist for general purpose DMA engines? Last time I looked at this problem nothing really existed. - kumar
