Based on comments from [1] discussion, it seems there is a need to have a generic support to configure dma device parameters. Series introduces support for setting up dma parameters based on device tree properties like 'dma-ranges' and 'dma-coherent'.
The 'dma-ranges' helps to take care of few DMAable system memory restrictions by use of dma_pfn_offset which we maintain now per device. Arch code then uses it for dma address translations for such cases. We also setup dma_mask accordingly during the device creation process. The 'dma-coherent' property is used to setup coherent dma_ops. Arches which are always coherent can make use of ARCH_IS_DMA_COHERENT to setup coherent dma_ops always irrespective of 'dma-coherent' property. Cc: Greg Kroah-Hartman <[email protected]> Cc: Russell King <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Olof Johansson <[email protected]> Cc: Grant Likely <[email protected]> Cc: Rob Herring <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Linus Walleij <[email protected]> Cc: Grygorii Strashko <[email protected]> Grygorii Strashko (3): of: introduce of_dma_get_range() helper of: configure the platform device dma_mask and dma_pfn_offset ARM: dma: Use dma_pfn_offset for dma address translation Santosh Shilimkar (4): device: introduce per device dma_pfn_offset of: introduce of_dma_is_coherent() helper of: Add set_arch_dma_coherent_ops() and setup coherent dma_ops ARM: dma: implement set_arch_dma_coherent_ops() arch/arm/include/asm/dma-mapping.h | 24 ++++- drivers/of/platform.c | 196 +++++++++++++++++++++++++++++++++++- include/linux/device.h | 2 + include/linux/dma-mapping.h | 7 ++ include/linux/of_platform.h | 14 +++ 5 files changed, 236 insertions(+), 7 deletions(-) Regards, Santosh [1] http://www.spinics.net/lists/arm-kernel/msg311678.html -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
