From 24ed5d2c07e36ebaf0e8ce483a41b8e44d7499d4 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Niklas=20S=C3=B6derlund?= Date: Wed, 10 Aug 2016 13:22:17 +0200 Subject: [PATCH] arm: dma-mapping: add {map,unmap}_resource for iommu ops MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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: Niklas Söderlund Reviewed-by: Laurent Pinchart Acked-by: Arnd Bergmann Signed-off-by: Vinod Koul --- arch/arm/mm/dma-mapping.c | 63 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index c6834c0cfd1c..746eb29c6f0c 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -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, }; /**