On Thu, Jun 02, 2016 at 02:58:07PM +0200, Niklas Söderlund wrote: > Hi Vinod, > > On 2016-06-01 23:36:11 +0530, Vinod Koul wrote: > > On Wed, Jun 01, 2016 at 05:22:23PM +0200, Niklas Söderlund wrote: > > > Hi, > > > > > > [In this v7 series I have tried to address the questions raised by Christoph > > > Hellwig and I hope it can awnser your concernes regarding dma-debug.] > > > > > > This series tries to solve the problem with DMA with device registers > > > (MMIO registers) that are behind an IOMMU for the rcar-dmac driver. A > > > recent patch '9575632 (dmaengine: make slave address physical)' > > > clarifies that DMA slave address provided by clients is the physical > > > address. This puts the task of mapping the DMA slave address from a > > > phys_addr_t to a dma_addr_t on the DMA engine. > > > > > > Without an IOMMU this is easy since the phys_addr_t and dma_addr_t are > > > the same and no special care is needed. However if you have a IOMMU you > > > need to map the DMA slave phys_addr_t to a dma_addr_t using something > > > like this. > > > > > > This series is based on top of v4.7-rc1. > > > > The dmanegine bits looks okay to me. Btw how is the merge planned for this? > > Do you wnat this to be merged thru dmaengine tree or something else? > > Yes, since the arm specific patch are depending on other parts of the > series I was hoping to be able to get Russells Ack on it and then try to > get it all in through the dmaengine tree. Sounds good to me.. > If you see a better way I'm happy to do it that way, let me know what > you think. I hold off v8 that adresses the issues Russell brought up a > few days untill I know what you think is best. -- ~Vinod
