On Wed, May 24, 2017 at 11:24:29AM +0100, Vladimir Murzin wrote: > This patch introduces default coherent DMA pool similar to default CMA > area concept. To keep other users safe code kept under CONFIG_ARM.
I don't see a CONFIG_ARM in the code, although parts of it are added under CONFIG_OF_RESERVED_MEM. But overall this code look a bit odd to me. As far as I can tell the dma-coherent.c code is for the case where we have a special piece of coherent memory close to a device. If you're allocating out of the global allocator the memory should come from the normal dma_ops ->alloc allocator - and also take the attrs into account (e.g. for DMA_ATTR_NON_CONSISTENT or DMA_ATTR_NO_KERNEL_MAPPING requests you don't need coherent memory)
