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Commit 24ed5d2c authored by Niklas Söderlund's avatar Niklas Söderlund Committed by Vinod Koul
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arm: dma-mapping: add {map,unmap}_resource for iommu ops 



Add methods to map/unmap device resources addresses for dma_map_ops that
are IOMMU aware. This is needed to map a device MMIO register from a
physical address.

Signed-off-by: default avatarNiklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: default avatarLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
parent 6f3d8796

arch/arm/mm/dma-mapping.c

+63 −0
Original line number Diff line number Diff line
@@ -2014,6 +2014,63 @@ static void arm_iommu_unmap_page(struct device *dev, dma_addr_t handle, 
	__free_iova(mapping, iova, len);

}



/**

 * arm_iommu_map_resource - map a device resource for DMA

 * @dev: valid struct device pointer

 * @phys_addr: physical address of resource

 * @size: size of resource to map

 * @dir: DMA transfer direction

 */

static dma_addr_t arm_iommu_map_resource(struct device *dev,

		phys_addr_t phys_addr, size_t size,

		enum dma_data_direction dir, unsigned long attrs)

{

	struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);

	dma_addr_t dma_addr;

	int ret, prot;

	phys_addr_t addr = phys_addr & PAGE_MASK;

	unsigned int offset = phys_addr & ~PAGE_MASK;

	size_t len = PAGE_ALIGN(size + offset);



	dma_addr = __alloc_iova(mapping, len);

	if (dma_addr == DMA_ERROR_CODE)

		return dma_addr;



	prot = __dma_direction_to_prot(dir) | IOMMU_MMIO;



	ret = iommu_map(mapping->domain, dma_addr, addr, len, prot);

	if (ret < 0)

		goto fail;



	return dma_addr + offset;

fail:

	__free_iova(mapping, dma_addr, len);

	return DMA_ERROR_CODE;

}



/**

 * arm_iommu_unmap_resource - unmap a device DMA resource

 * @dev: valid struct device pointer

 * @dma_handle: DMA address to resource

 * @size: size of resource to map

 * @dir: DMA transfer direction

 */

static void arm_iommu_unmap_resource(struct device *dev, dma_addr_t dma_handle,

		size_t size, enum dma_data_direction dir,

		unsigned long attrs)

{

	struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);

	dma_addr_t iova = dma_handle & PAGE_MASK;

	unsigned int offset = dma_handle & ~PAGE_MASK;

	size_t len = PAGE_ALIGN(size + offset);



	if (!iova)

		return;



	iommu_unmap(mapping->domain, iova, len);

	__free_iova(mapping, iova, len);

}



static void arm_iommu_sync_single_for_cpu(struct device *dev,

		dma_addr_t handle, size_t size, enum dma_data_direction dir)

{
@@ -2057,6 +2114,9 @@ struct dma_map_ops iommu_ops = { 
	.unmap_sg		= arm_iommu_unmap_sg,

	.sync_sg_for_cpu	= arm_iommu_sync_sg_for_cpu,

	.sync_sg_for_device	= arm_iommu_sync_sg_for_device,



	.map_resource		= arm_iommu_map_resource,

	.unmap_resource		= arm_iommu_unmap_resource,

};



struct dma_map_ops iommu_coherent_ops = {
@@ -2070,6 +2130,9 @@ struct dma_map_ops iommu_coherent_ops = { 


	.map_sg		= arm_coherent_iommu_map_sg,

	.unmap_sg	= arm_coherent_iommu_unmap_sg,



	.map_resource	= arm_iommu_map_resource,

	.unmap_resource	= arm_iommu_unmap_resource,

};



/**