On Fri, 21 Jun 2013 18:03:44 +0200 Joerg Roedel <[email protected]> wrote:
> On Fri, Jun 21, 2013 at 09:17:59AM +0200, Marek Szyprowski wrote: > > Using DMA attributes for this seems to be a bad idea. The dma direction > > parameter is much more appropriate. Will Deacon recently posted a patch > > which does it right, see: > > > > https://git.linaro.org/gitweb?p=people/mszyprowski/linux-dma-mapping.git;a=commit;h=8fc3749bd31d139db58f874e093255fe62505968 > > Agreed, that is one usecase the dma-direction parameter was made for. In > particular: > > DMA_FROM_DEVICE -> Write only mapping > DMA_TO_DEVICE -> Read only mapping > DMA_BIDIRECTIONAL -> Read/Write mapping > > So no need to use the dma attributes for that. Ok, thanks. One more question, IOMMU H/W sometimes supports more platform specific attributes than READ/WRITE. For example, in OMAP, #define IOMMU_FLAG (IOVMF_ENDIAN_LITTLE | IOVMF_ELSZ_8) Is there any way to deal with those platform specific attrs from DMA mapping API POV? -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
