On Mon, Oct 14, 2019 at 08:31:02PM +0200, Nicolas Saenz Julienne wrote: > the Raspberry Pi 4 offers up to 4GB of memory, of which only the first > is DMA capable device wide. This forces us to use of bounce buffers, > which are currently not very well supported by ARM's custom DMA ops. > Among other things the current mechanism (see dmabounce.c) isn't > suitable for high memory. Instead of fixing it, this series introduces a > way of selecting dma-direct as the default DMA ops provider which allows > for the Raspberry Pi to make use of swiotlb. I presume these patches go on top of this series: http://lkml.kernel.org/r/20190911182546.17094-1-nsaenzjulienne@xxxxxxx which I queued here: https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git/log/?h=for-next/zone-dma -- Catalin
