| Becky Bruce | 8dd0e95 | 2008-09-08 09:09:53 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corporation |
| 3 | * |
| 4 | * Provide default implementations of the DMA mapping callbacks for |
| 5 | * busses using the iommu infrastructure |
| 6 | */ |
| 7 | |
| 8 | #include <asm/iommu.h> |
| 9 | |
| 10 | /* |
| 11 | * Generic iommu implementation |
| 12 | */ |
| 13 | |
| 14 | /* Allocates a contiguous real buffer and creates mappings over it. |
| 15 | * Returns the virtual address of the buffer and sets dma_handle |
| 16 | * to the dma address (mapping) of the first page. |
| 17 | */ |
| 18 | static void *dma_iommu_alloc_coherent(struct device *dev, size_t size, |
| 19 | dma_addr_t *dma_handle, gfp_t flag) |
| 20 | { |
| 21 | return iommu_alloc_coherent(dev, dev->archdata.dma_data, size, |
| 22 | dma_handle, device_to_mask(dev), flag, |
| 23 | dev->archdata.numa_node); |
| 24 | } |
| 25 | |
| 26 | static void dma_iommu_free_coherent(struct device *dev, size_t size, |
| 27 | void *vaddr, dma_addr_t dma_handle) |
| 28 | { |
| 29 | iommu_free_coherent(dev->archdata.dma_data, size, vaddr, dma_handle); |
| 30 | } |
| 31 | |
| 32 | /* Creates TCEs for a user provided buffer. The user buffer must be |
| 33 | * contiguous real kernel storage (not vmalloc). The address of the buffer |
| 34 | * passed here is the kernel (virtual) address of the buffer. The buffer |
| 35 | * need not be page aligned, the dma_addr_t returned will point to the same |
| 36 | * byte within the page as vaddr. |
| 37 | */ |
| 38 | static dma_addr_t dma_iommu_map_single(struct device *dev, void *vaddr, |
| 39 | size_t size, |
| 40 | enum dma_data_direction direction, |
| 41 | struct dma_attrs *attrs) |
| 42 | { |
| 43 | return iommu_map_single(dev, dev->archdata.dma_data, vaddr, size, |
| 44 | device_to_mask(dev), direction, attrs); |
| 45 | } |
| 46 | |
| 47 | |
| 48 | static void dma_iommu_unmap_single(struct device *dev, dma_addr_t dma_handle, |
| 49 | size_t size, |
| 50 | enum dma_data_direction direction, |
| 51 | struct dma_attrs *attrs) |
| 52 | { |
| 53 | iommu_unmap_single(dev->archdata.dma_data, dma_handle, size, direction, |
| 54 | attrs); |
| 55 | } |
| 56 | |
| 57 | |
| 58 | static int dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist, |
| 59 | int nelems, enum dma_data_direction direction, |
| 60 | struct dma_attrs *attrs) |
| 61 | { |
| 62 | return iommu_map_sg(dev, dev->archdata.dma_data, sglist, nelems, |
| 63 | device_to_mask(dev), direction, attrs); |
| 64 | } |
| 65 | |
| 66 | static void dma_iommu_unmap_sg(struct device *dev, struct scatterlist *sglist, |
| 67 | int nelems, enum dma_data_direction direction, |
| 68 | struct dma_attrs *attrs) |
| 69 | { |
| 70 | iommu_unmap_sg(dev->archdata.dma_data, sglist, nelems, direction, |
| 71 | attrs); |
| 72 | } |
| 73 | |
| 74 | /* We support DMA to/from any memory page via the iommu */ |
| 75 | static int dma_iommu_dma_supported(struct device *dev, u64 mask) |
| 76 | { |
| 77 | struct iommu_table *tbl = dev->archdata.dma_data; |
| 78 | |
| 79 | if (!tbl || tbl->it_offset > mask) { |
| 80 | printk(KERN_INFO |
| 81 | "Warning: IOMMU offset too big for device mask\n"); |
| 82 | if (tbl) |
| 83 | printk(KERN_INFO |
| 84 | "mask: 0x%08lx, table offset: 0x%08lx\n", |
| 85 | mask, tbl->it_offset); |
| 86 | else |
| 87 | printk(KERN_INFO "mask: 0x%08lx, table unavailable\n", |
| 88 | mask); |
| 89 | return 0; |
| 90 | } else |
| 91 | return 1; |
| 92 | } |
| 93 | |
| 94 | struct dma_mapping_ops dma_iommu_ops = { |
| 95 | .alloc_coherent = dma_iommu_alloc_coherent, |
| 96 | .free_coherent = dma_iommu_free_coherent, |
| 97 | .map_single = dma_iommu_map_single, |
| 98 | .unmap_single = dma_iommu_unmap_single, |
| 99 | .map_sg = dma_iommu_map_sg, |
| 100 | .unmap_sg = dma_iommu_unmap_sg, |
| 101 | .dma_supported = dma_iommu_dma_supported, |
| 102 | }; |
| 103 | EXPORT_SYMBOL(dma_iommu_ops); |