2 * Copyright (c) 2004 Hewlett-Packard Development Company, L.P.
3 * Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
5 * This is a pseudo I/O MMU which dispatches to the hardware I/O MMU
6 * whenever possible. We assume that the hardware I/O MMU requires
7 * full 32-bit addressability, as is the case, e.g., for HP zx1-based
8 * systems (there, the I/O MMU window is mapped at 3-4GB). If a
9 * device doesn't provide full 32-bit addressability, we fall back on
10 * the sw I/O TLB. This is good enough to let us support broken
11 * hardware such as soundcards which have a DMA engine that can
12 * address only 28 bits.
15 #include <linux/device.h>
16 #include <linux/swiotlb.h>
18 #include <asm/machvec.h>
20 /* swiotlb declarations & definitions: */
21 extern int swiotlb_late_init_with_default_size (size_t size);
23 /* hwiommu declarations & definitions: */
25 extern ia64_mv_dma_alloc_coherent sba_alloc_coherent;
26 extern ia64_mv_dma_free_coherent sba_free_coherent;
27 extern ia64_mv_dma_map_single_attrs sba_map_single_attrs;
28 extern ia64_mv_dma_unmap_single_attrs sba_unmap_single_attrs;
29 extern ia64_mv_dma_map_sg_attrs sba_map_sg_attrs;
30 extern ia64_mv_dma_unmap_sg_attrs sba_unmap_sg_attrs;
31 extern ia64_mv_dma_supported sba_dma_supported;
32 extern ia64_mv_dma_mapping_error sba_dma_mapping_error;
34 #define hwiommu_alloc_coherent sba_alloc_coherent
35 #define hwiommu_free_coherent sba_free_coherent
36 #define hwiommu_map_single_attrs sba_map_single_attrs
37 #define hwiommu_unmap_single_attrs sba_unmap_single_attrs
38 #define hwiommu_map_sg_attrs sba_map_sg_attrs
39 #define hwiommu_unmap_sg_attrs sba_unmap_sg_attrs
40 #define hwiommu_dma_supported sba_dma_supported
41 #define hwiommu_dma_mapping_error sba_dma_mapping_error
42 #define hwiommu_sync_single_for_cpu machvec_dma_sync_single
43 #define hwiommu_sync_sg_for_cpu machvec_dma_sync_sg
44 #define hwiommu_sync_single_for_device machvec_dma_sync_single
45 #define hwiommu_sync_sg_for_device machvec_dma_sync_sg
49 * Note: we need to make the determination of whether or not to use
50 * the sw I/O TLB based purely on the device structure. Anything else
51 * would be unreliable or would be too intrusive.
54 use_swiotlb (struct device *dev)
56 return dev && dev->dma_mask && !hwiommu_dma_supported(dev, *dev->dma_mask);
62 /* default to a smallish 2MB sw I/O TLB */
63 if (swiotlb_late_init_with_default_size (2 * (1<<20)) != 0) {
64 #ifdef CONFIG_IA64_GENERIC
65 /* Better to have normal DMA than panic */
66 printk(KERN_WARNING "%s: Failed to initialize software I/O TLB,"
67 " reverting to hpzx1 platform vector\n", __func__);
68 machvec_init("hpzx1");
70 panic("Unable to initialize software I/O TLB services");
76 hwsw_alloc_coherent (struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flags)
79 return swiotlb_alloc_coherent(dev, size, dma_handle, flags);
81 return hwiommu_alloc_coherent(dev, size, dma_handle, flags);
85 hwsw_free_coherent (struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle)
88 swiotlb_free_coherent(dev, size, vaddr, dma_handle);
90 hwiommu_free_coherent(dev, size, vaddr, dma_handle);
94 hwsw_map_single_attrs(struct device *dev, void *addr, size_t size, int dir,
95 struct dma_attrs *attrs)
98 return swiotlb_map_single_attrs(dev, addr, size, dir, attrs);
100 return hwiommu_map_single_attrs(dev, addr, size, dir, attrs);
102 EXPORT_SYMBOL(hwsw_map_single_attrs);
105 hwsw_unmap_single_attrs(struct device *dev, dma_addr_t iova, size_t size,
106 int dir, struct dma_attrs *attrs)
108 if (use_swiotlb(dev))
109 return swiotlb_unmap_single_attrs(dev, iova, size, dir, attrs);
111 return hwiommu_unmap_single_attrs(dev, iova, size, dir, attrs);
113 EXPORT_SYMBOL(hwsw_unmap_single_attrs);
116 hwsw_map_sg_attrs(struct device *dev, struct scatterlist *sglist, int nents,
117 int dir, struct dma_attrs *attrs)
119 if (use_swiotlb(dev))
120 return swiotlb_map_sg_attrs(dev, sglist, nents, dir, attrs);
122 return hwiommu_map_sg_attrs(dev, sglist, nents, dir, attrs);
124 EXPORT_SYMBOL(hwsw_map_sg_attrs);
127 hwsw_unmap_sg_attrs(struct device *dev, struct scatterlist *sglist, int nents,
128 int dir, struct dma_attrs *attrs)
130 if (use_swiotlb(dev))
131 return swiotlb_unmap_sg_attrs(dev, sglist, nents, dir, attrs);
133 return hwiommu_unmap_sg_attrs(dev, sglist, nents, dir, attrs);
135 EXPORT_SYMBOL(hwsw_unmap_sg_attrs);
138 hwsw_sync_single_for_cpu (struct device *dev, dma_addr_t addr, size_t size, int dir)
140 if (use_swiotlb(dev))
141 swiotlb_sync_single_for_cpu(dev, addr, size, dir);
143 hwiommu_sync_single_for_cpu(dev, addr, size, dir);
147 hwsw_sync_sg_for_cpu (struct device *dev, struct scatterlist *sg, int nelems, int dir)
149 if (use_swiotlb(dev))
150 swiotlb_sync_sg_for_cpu(dev, sg, nelems, dir);
152 hwiommu_sync_sg_for_cpu(dev, sg, nelems, dir);
156 hwsw_sync_single_for_device (struct device *dev, dma_addr_t addr, size_t size, int dir)
158 if (use_swiotlb(dev))
159 swiotlb_sync_single_for_device(dev, addr, size, dir);
161 hwiommu_sync_single_for_device(dev, addr, size, dir);
165 hwsw_sync_sg_for_device (struct device *dev, struct scatterlist *sg, int nelems, int dir)
167 if (use_swiotlb(dev))
168 swiotlb_sync_sg_for_device(dev, sg, nelems, dir);
170 hwiommu_sync_sg_for_device(dev, sg, nelems, dir);
174 hwsw_dma_supported (struct device *dev, u64 mask)
176 if (hwiommu_dma_supported(dev, mask))
178 return swiotlb_dma_supported(dev, mask);
182 hwsw_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
184 return hwiommu_dma_mapping_error(dev, dma_addr) ||
185 swiotlb_dma_mapping_error(dev, dma_addr);
188 EXPORT_SYMBOL(hwsw_dma_mapping_error);
189 EXPORT_SYMBOL(hwsw_dma_supported);
190 EXPORT_SYMBOL(hwsw_alloc_coherent);
191 EXPORT_SYMBOL(hwsw_free_coherent);
192 EXPORT_SYMBOL(hwsw_sync_single_for_cpu);
193 EXPORT_SYMBOL(hwsw_sync_single_for_device);
194 EXPORT_SYMBOL(hwsw_sync_sg_for_cpu);
195 EXPORT_SYMBOL(hwsw_sync_sg_for_device);