Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-09-26 Thread Vinod Koul
On Wed, Aug 10, 2016 at 01:22:13PM +0200, Niklas Söderlund wrote: > Hi, > > 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

Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-09-23 Thread Niklas Söderlund
Hi Vinod, On 2016-09-15 21:56:51 +0530, Vinod Koul wrote: > On Wed, Aug 10, 2016 at 11:07:10PM +0530, Vinod Koul wrote: > > On Wed, Aug 10, 2016 at 01:22:13PM +0200, Niklas Söderlund wrote: > > > Hi, > > > > > > This series tries to solve the problem with DMA with device registers > > > (MMIO

Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-09-16 Thread Laurent Pinchart
Hi Robin, On Friday 16 Sep 2016 13:49:21 Robin Murphy wrote: > On 16/09/16 13:05, Laurent Pinchart wrote: > [...] > > One concern I have is that we might get an awkward situation if we ever > encounter one DMA engine hardware that is used in different systems > that all have an

Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-09-16 Thread Laurent Pinchart
Hi Arnd, On Friday 16 Sep 2016 14:22:31 Arnd Bergmann wrote: > On Friday, September 16, 2016 3:09:29 PM CEST Laurent Pinchart wrote: > >> I wasn't thinking quite that far, though that is also a theoretical > >> problem. However, the simple solution would be to have a bit in the DMA > >> specifier

Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-09-16 Thread Robin Murphy
On 16/09/16 13:05, Laurent Pinchart wrote: [...] One concern I have is that we might get an awkward situation if we ever encounter one DMA engine hardware that is used in different systems that all have an IOMMU, but on some of them the connection between the DMA master and the

Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-09-16 Thread Arnd Bergmann
On Friday, September 16, 2016 3:09:29 PM CEST Laurent Pinchart wrote: > > I wasn't thinking quite that far, though that is also a theoretical > > problem. However, the simple solution would be to have a bit in the DMA > > specifier let the driver know whether translation is needed or not. > > > >

Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-09-16 Thread Laurent Pinchart
Hi Arnd, On Friday 16 Sep 2016 14:02:35 Arnd Bergmann wrote: > On Friday, September 16, 2016 12:48:23 PM CEST Laurent Pinchart wrote: > > On Friday 16 Sep 2016 11:07:48 Arnd Bergmann wrote: > >> On Thursday, September 15, 2016 9:56:51 PM CEST Vinod Koul wrote: > >>> On Wed, Aug 10, 2016 at

Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-09-16 Thread Laurent Pinchart
Hi Rubin, On Friday 16 Sep 2016 11:36:29 Robin Murphy wrote: > On 16/09/16 10:48, Laurent Pinchart wrote: > > On Friday 16 Sep 2016 11:07:48 Arnd Bergmann wrote: > >> On Thursday, September 15, 2016 9:56:51 PM CEST Vinod Koul wrote: > >>> On Wed, Aug 10, 2016 at 11:07:10PM +0530, Vinod Koul

Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-09-16 Thread Arnd Bergmann
On Friday, September 16, 2016 12:48:23 PM CEST Laurent Pinchart wrote: > On Friday 16 Sep 2016 11:07:48 Arnd Bergmann wrote: > > On Thursday, September 15, 2016 9:56:51 PM CEST Vinod Koul wrote: > > > On Wed, Aug 10, 2016 at 11:07:10PM +0530, Vinod Koul wrote: > > >> On Wed, Aug 10, 2016 at

Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-09-16 Thread Robin Murphy
On 16/09/16 10:48, Laurent Pinchart wrote: > Hi Arnd, > > On Friday 16 Sep 2016 11:07:48 Arnd Bergmann wrote: >> On Thursday, September 15, 2016 9:56:51 PM CEST Vinod Koul wrote: >>> On Wed, Aug 10, 2016 at 11:07:10PM +0530, Vinod Koul wrote: On Wed, Aug 10, 2016 at 01:22:13PM +0200, Niklas

Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-09-16 Thread Laurent Pinchart
Hi Arnd, On Friday 16 Sep 2016 11:07:48 Arnd Bergmann wrote: > On Thursday, September 15, 2016 9:56:51 PM CEST Vinod Koul wrote: > > On Wed, Aug 10, 2016 at 11:07:10PM +0530, Vinod Koul wrote: > >> On Wed, Aug 10, 2016 at 01:22:13PM +0200, Niklas Söderlund wrote: > >>> Hi, > >>> > >>> This

Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-09-16 Thread Arnd Bergmann
On Thursday, September 15, 2016 9:56:51 PM CEST Vinod Koul wrote: > On Wed, Aug 10, 2016 at 11:07:10PM +0530, Vinod Koul wrote: > > On Wed, Aug 10, 2016 at 01:22:13PM +0200, Niklas Söderlund wrote: > > > Hi, > > > > > > This series tries to solve the problem with DMA with device registers > > >

Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-09-15 Thread Vinod Koul
On Wed, Aug 10, 2016 at 11:07:10PM +0530, Vinod Koul wrote: > On Wed, Aug 10, 2016 at 01:22:13PM +0200, Niklas Söderlund wrote: > > Hi, > > > > 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 > >

Re: [PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers

2016-08-10 Thread Vinod Koul
On Wed, Aug 10, 2016 at 01:22:13PM +0200, Niklas Söderlund wrote: > Hi, > > 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