2 * Copyright (C) 2004 IBM
4 * Implements the generic device dma API for powerpc.
5 * the pci and vio busses
7 #ifndef _ASM_DMA_MAPPING_H
8 #define _ASM_DMA_MAPPING_H
11 #include <linux/types.h>
12 #include <linux/cache.h>
13 /* need struct page definitions */
15 #include <linux/scatterlist.h>
16 #include <linux/dma-debug.h>
18 #include <asm/swiotlb.h>
20 /* Some dma direct funcs must be visible for use in other dma_ops */
21 extern void *__dma_direct_alloc_coherent(struct device *dev, size_t size,
22 dma_addr_t *dma_handle, gfp_t flag,
24 extern void __dma_direct_free_coherent(struct device *dev, size_t size,
25 void *vaddr, dma_addr_t dma_handle,
27 extern int dma_direct_mmap_coherent(struct device *dev,
28 struct vm_area_struct *vma,
29 void *cpu_addr, dma_addr_t handle,
30 size_t size, unsigned long attrs);
32 #ifdef CONFIG_NOT_COHERENT_CACHE
34 * DMA-consistent mapping functions for PowerPCs that don't support
35 * cache snooping. These allocate/free a region of uncached mapped
36 * memory space for use with DMA devices. Alternatively, you could
37 * allocate the space "normally" and use the cache management functions
38 * to ensure it is consistent.
41 extern void *__dma_alloc_coherent(struct device *dev, size_t size,
42 dma_addr_t *handle, gfp_t gfp);
43 extern void __dma_free_coherent(size_t size, void *vaddr);
44 extern void __dma_sync(void *vaddr, size_t size, int direction);
45 extern void __dma_sync_page(struct page *page, unsigned long offset,
46 size_t size, int direction);
47 extern unsigned long __dma_get_coherent_pfn(unsigned long cpu_addr);
49 #else /* ! CONFIG_NOT_COHERENT_CACHE */
51 * Cache coherent cores.
54 #define __dma_alloc_coherent(dev, gfp, size, handle) NULL
55 #define __dma_free_coherent(size, addr) ((void)0)
56 #define __dma_sync(addr, size, rw) ((void)0)
57 #define __dma_sync_page(pg, off, sz, rw) ((void)0)
59 #endif /* ! CONFIG_NOT_COHERENT_CACHE */
61 static inline unsigned long device_to_mask(struct device *dev)
63 if (dev->dma_mask && *dev->dma_mask)
64 return *dev->dma_mask;
65 /* Assume devices without mask can take 32 bit addresses */
70 * Available generic sets of operations
73 extern struct dma_map_ops dma_iommu_ops;
75 extern const struct dma_map_ops dma_direct_ops;
77 static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
79 /* We don't handle the NULL dev case for ISA for now. We could
80 * do it via an out of line call but it is not needed for now. The
81 * only ISA DMA device we support is the floppy and we have a hack
82 * in the floppy driver directly to get a device for us.
90 * Get the dma offset on configurations where the dma address can be determined
91 * from the physical address by looking at a simple offset. Direct dma and
92 * swiotlb use this function, but it is typically not used by implementations
95 static inline dma_addr_t get_dma_offset(struct device *dev)
98 return dev->archdata.dma_offset;
100 return PCI_DRAM_OFFSET;
103 static inline void set_dma_offset(struct device *dev, dma_addr_t off)
106 dev->archdata.dma_offset = off;
109 /* this will be removed soon */
110 #define flush_write_buffers()
112 #define HAVE_ARCH_DMA_SET_MASK 1
113 extern int dma_set_mask(struct device *dev, u64 dma_mask);
115 extern u64 __dma_get_required_mask(struct device *dev);
117 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
119 #ifdef CONFIG_SWIOTLB
120 struct dev_archdata *sd = &dev->archdata;
122 if (sd->max_direct_dma_addr && addr + size > sd->max_direct_dma_addr)
129 return addr + size - 1 <= *dev->dma_mask;
132 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
134 return paddr + get_dma_offset(dev);
137 static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
139 return daddr - get_dma_offset(dev);
142 #define ARCH_HAS_DMA_MMAP_COHERENT
144 static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
145 enum dma_data_direction direction)
147 BUG_ON(direction == DMA_NONE);
148 __dma_sync(vaddr, size, (int)direction);
151 #endif /* __KERNEL__ */
152 #endif /* _ASM_DMA_MAPPING_H */