Messages in this thread | | | Date | Tue, 9 Mar 2010 09:14:03 +0000 | From | Russell King - ARM Linux <> | Subject | Re: DMA using data buffer vmapped in kernel space |
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On Tue, Mar 09, 2010 at 03:45:54PM +0800, Lin Mac wrote: > I had encounter a similiar problem and I simply allocated a new > buffer, copy the data, then DMA. It seems slow and stupid. > > I'm wondering wether could I translate the vmap virt to phys(don't > know how to yet), then use phys_to_virt to get the virt in > direct-mapped memory region? > > Is there other possible ways?
I think you need to talk to the firmware people... which is unfortunately orphaned.
What you could do is prepare a patch to allow the firmware support to export a scatterlist via the struct firmware, and then use that with dma_map_sg(). Let's hope that the SPI interfaces support scatterlists.
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