Hi Niklas, Thank you for the patch.
On Wednesday 10 February 2016 01:57:54 Niklas Söderlund wrote: > 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 <[email protected]> Reviewed-by: Laurent Pinchart <[email protected]> > --- > 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 0eca381..ae2b175 100644 > --- a/arch/arm/mm/dma-mapping.c > +++ b/arch/arm/mm/dma-mapping.c > @@ -1814,6 +1814,63 @@ 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, struct dma_attrs *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; > + int offset = phys_addr & ~PAGE_MASK; > + int len = PAGE_ALIGN(size + offset); > + > + dma_addr = __alloc_iova(mapping, size); > + 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, size); > + 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, > + struct dma_attrs *attrs) > +{ > + struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev); > + dma_addr_t iova = dma_handle & PAGE_MASK; > + int offset = dma_handle & ~PAGE_MASK; > + int 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) > { > @@ -1858,6 +1915,9 @@ struct dma_map_ops iommu_ops = { > .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, > + > .set_dma_mask = arm_dma_set_mask, > }; > > @@ -1873,6 +1933,9 @@ 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, > + > .set_dma_mask = arm_dma_set_mask, > }; -- Regards, Laurent Pinchart
