Messages in this thread | | | Date | Tue, 22 Mar 2016 12:34:08 +0000 | From | Russell King - ARM Linux <> | Subject | Re: [Query] doubt on parameters passed to dma_map_single_attrs() API |
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On Tue, Mar 22, 2016 at 03:53:02PM +0530, Sodagudi Prasad wrote: > > Hi All, > > Would like to check whether the dma_map_single_attrs() API, can accept ptr > variable from high memory or not?
It can't. Direct mapped, lowmem only.
No pointers allowed from dma_alloc_coherent(), dma_alloc_writecombine(), ioremap(), vmalloc(), kmap(), kmap_atomic() or similar function, or derived from one of these.
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