From mboxrd@z Thu Jan 1 00:00:00 1970 From: m.szyprowski@samsung.com (Marek Szyprowski) Date: Mon, 15 Oct 2012 16:03:50 +0200 Subject: [RFC 0/2] DMA-mapping & IOMMU - physically contiguous allocations Message-ID: <1350309832-18461-1-git-send-email-m.szyprowski@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hello, Some devices, which have IOMMU, for some use cases might require to allocate a buffers for DMA which is contiguous in physical memory. Such use cases appears for example in DRM subsystem when one wants to improve performance or use secure buffer protection. I would like to ask if adding a new attribute, as proposed in this RFC is a good idea? I feel that it might be an attribute just for a single driver, but I would like to know your opinion. Should we look for other solution? Best regards -- Marek Szyprowski Samsung Poland R&D Center Marek Szyprowski (2): common: DMA-mapping: add DMA_ATTR_FORCE_CONTIGUOUS attribute ARM: dma-mapping: add support for DMA_ATTR_FORCE_CONTIGUOUS attribute Documentation/DMA-attributes.txt | 9 +++++++++ arch/arm/mm/dma-mapping.c | 41 ++++++++++++++++++++++++++++++-------- include/linux/dma-attrs.h | 1 + 3 files changed, 43 insertions(+), 8 deletions(-) -- 1.7.9.5