linux/arch/arm/include/asm/dma-iommu.h

#ifndef ASMARM_DMA_IOMMU_H
#define ASMARM_DMA_IOMMU_H

#ifdef __KERNEL__

#include <linux/mm_types.h>
#include <linux/scatterlist.h>
#include <linux/dma-debug.h>
#include <linux/kmemcheck.h>
#include <linux/kref.h>

struct dma_iommu_mapping {
	/* iommu specific data */
	struct iommu_domain	*domain;

	void			*bitmap;
	size_t			bits;
	unsigned int		order;
	dma_addr_t		base;

	spinlock_t		lock;
	struct kref		kref;
};

struct dma_iommu_mapping *
arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, size_t size,
			 int order);

void arm_iommu_release_mapping(struct dma_iommu_mapping *mapping);

int arm_iommu_attach_device(struct device *dev,
					struct dma_iommu_mapping *mapping);
void arm_iommu_detach_device(struct device *dev);

#endif /* __KERNEL__ */
#endif
ARM: dma-mapping: add support for IOMMU mapper This patch add a complete implementation of DMA-mapping API for devices which have IOMMU support. This implementation tries to optimize dma address space usage by remapping all possible physical memory chunks into a single dma address space chunk. DMA address space is managed on top of the bitmap stored in the dma_iommu_mapping structure stored in device->archdata. Platform setup code has to initialize parameters of the dma address space (base address, size, allocation precision order) with arm_iommu_create_mapping() function. To reduce the size of the bitmap, all allocations are aligned to the specified order of base 4 KiB pages. dma_alloc_* functions allocate physical memory in chunks, each with alloc_pages() function to avoid failing if the physical memory gets fragmented. In worst case the allocated buffer is composed of 4 KiB page chunks. dma_map_sg() function minimizes the total number of dma address space chunks by merging of physical memory chunks into one larger dma address space chunk. If requested chunk (scatter list entry) boundaries match physical page boundaries, most calls to dma_map_sg() requests will result in creating only one chunk in dma address space. dma_map_page() simply creates a mapping for the given page(s) in the dma address space. All dma functions also perform required cache operation like their counterparts from the arm linear physical memory mapping version. This patch contains code and fixes kindly provided by: - Krishna Reddy <vdumpa@nvidia.com>, - Andrzej Pietrasiewicz <andrzej.p@samsung.com>, - Hiroshi DOYU <hdoyu@nvidia.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-By: Subash Patel <subash.ramaswamy@linaro.org> 2012-05-16 13:48:21 +00:00			`#ifndef ASMARM_DMA_IOMMU_H`
			`#define ASMARM_DMA_IOMMU_H`

			`#ifdef __KERNEL__`

			`#include <linux/mm_types.h>`
			`#include <linux/scatterlist.h>`
			`#include <linux/dma-debug.h>`
			`#include <linux/kmemcheck.h>`
ARM: iommu: Include linux/kref.h in asm/dma-iommu.h The dma_iommu_mapping structure defined in asm/dma-iommu.h embeds a struct kref, include the appropriate header file. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> 2012-12-16 12:32:03 +00:00			`#include <linux/kref.h>`
ARM: dma-mapping: add support for IOMMU mapper This patch add a complete implementation of DMA-mapping API for devices which have IOMMU support. This implementation tries to optimize dma address space usage by remapping all possible physical memory chunks into a single dma address space chunk. DMA address space is managed on top of the bitmap stored in the dma_iommu_mapping structure stored in device->archdata. Platform setup code has to initialize parameters of the dma address space (base address, size, allocation precision order) with arm_iommu_create_mapping() function. To reduce the size of the bitmap, all allocations are aligned to the specified order of base 4 KiB pages. dma_alloc_* functions allocate physical memory in chunks, each with alloc_pages() function to avoid failing if the physical memory gets fragmented. In worst case the allocated buffer is composed of 4 KiB page chunks. dma_map_sg() function minimizes the total number of dma address space chunks by merging of physical memory chunks into one larger dma address space chunk. If requested chunk (scatter list entry) boundaries match physical page boundaries, most calls to dma_map_sg() requests will result in creating only one chunk in dma address space. dma_map_page() simply creates a mapping for the given page(s) in the dma address space. All dma functions also perform required cache operation like their counterparts from the arm linear physical memory mapping version. This patch contains code and fixes kindly provided by: - Krishna Reddy <vdumpa@nvidia.com>, - Andrzej Pietrasiewicz <andrzej.p@samsung.com>, - Hiroshi DOYU <hdoyu@nvidia.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-By: Subash Patel <subash.ramaswamy@linaro.org> 2012-05-16 13:48:21 +00:00
			`struct dma_iommu_mapping {`
			`/* iommu specific data */`
			`struct iommu_domain *domain;`

			`void *bitmap;`
			`size_t bits;`
			`unsigned int order;`
			`dma_addr_t base;`

			`spinlock_t lock;`
			`struct kref kref;`
			`};`

			`struct dma_iommu_mapping *`
			`arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, size_t size,`
			`int order);`

			`void arm_iommu_release_mapping(struct dma_iommu_mapping *mapping);`

			`int arm_iommu_attach_device(struct device *dev,`
			`struct dma_iommu_mapping *mapping);`
ARM: dma-mapping: Add arm_iommu_detach_device() A counter part of arm_iommu_attach_device(). Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> 2013-01-24 13:16:57 +00:00			`void arm_iommu_detach_device(struct device *dev);`
ARM: dma-mapping: add support for IOMMU mapper This patch add a complete implementation of DMA-mapping API for devices which have IOMMU support. This implementation tries to optimize dma address space usage by remapping all possible physical memory chunks into a single dma address space chunk. DMA address space is managed on top of the bitmap stored in the dma_iommu_mapping structure stored in device->archdata. Platform setup code has to initialize parameters of the dma address space (base address, size, allocation precision order) with arm_iommu_create_mapping() function. To reduce the size of the bitmap, all allocations are aligned to the specified order of base 4 KiB pages. dma_alloc_* functions allocate physical memory in chunks, each with alloc_pages() function to avoid failing if the physical memory gets fragmented. In worst case the allocated buffer is composed of 4 KiB page chunks. dma_map_sg() function minimizes the total number of dma address space chunks by merging of physical memory chunks into one larger dma address space chunk. If requested chunk (scatter list entry) boundaries match physical page boundaries, most calls to dma_map_sg() requests will result in creating only one chunk in dma address space. dma_map_page() simply creates a mapping for the given page(s) in the dma address space. All dma functions also perform required cache operation like their counterparts from the arm linear physical memory mapping version. This patch contains code and fixes kindly provided by: - Krishna Reddy <vdumpa@nvidia.com>, - Andrzej Pietrasiewicz <andrzej.p@samsung.com>, - Hiroshi DOYU <hdoyu@nvidia.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-By: Subash Patel <subash.ramaswamy@linaro.org> 2012-05-16 13:48:21 +00:00
			`#endif /* __KERNEL__ */`
			`#endif`