arch/powerpc/include/asm/dma-mapping.h

   1 /*
   2  * Copyright (C) 2004 IBM
   3  *
   4  * Implements the generic device dma API for powerpc.
   5  * the pci and vio busses
   6  */
   7 #ifndef _ASM_DMA_MAPPING_H
   8 #define _ASM_DMA_MAPPING_H
   9 #ifdef __KERNEL__
  10
  11 #include <linux/types.h>
  12 #include <linux/cache.h>
  13 /* need struct page definitions */
  14 #include <linux/mm.h>
  15 #include <linux/scatterlist.h>
  16 #include <linux/dma-attrs.h>
  17 #include <linux/dma-debug.h>
  18 #include <asm/io.h>
  19 #include <asm/swiotlb.h>
  20
  21 #ifdef CONFIG_PPC64
  22 #define DMA_ERROR_CODE          (~(dma_addr_t)0x0)
  23 #endif
  24
  25 /* Some dma direct funcs must be visible for use in other dma_ops */
  26 extern void *__dma_direct_alloc_coherent(struct device *dev, size_t size,
  27                                          dma_addr_t *dma_handle, gfp_t flag,
  28                                          struct dma_attrs *attrs);
  29 extern void __dma_direct_free_coherent(struct device *dev, size_t size,
  30                                        void *vaddr, dma_addr_t dma_handle,
  31                                        struct dma_attrs *attrs);
  32 extern int dma_direct_mmap_coherent(struct device *dev,
  33                                     struct vm_area_struct *vma,
  34                                     void *cpu_addr, dma_addr_t handle,
  35                                     size_t size, struct dma_attrs *attrs);
  36
  37 #ifdef CONFIG_NOT_COHERENT_CACHE
  38 /*
  39  * DMA-consistent mapping functions for PowerPCs that don't support
  40  * cache snooping.  These allocate/free a region of uncached mapped
  41  * memory space for use with DMA devices.  Alternatively, you could
  42  * allocate the space "normally" and use the cache management functions
  43  * to ensure it is consistent.
  44  */
  45 struct device;
  46 extern void *__dma_alloc_coherent(struct device *dev, size_t size,
  47                                   dma_addr_t *handle, gfp_t gfp);
  48 extern void __dma_free_coherent(size_t size, void *vaddr);
  49 extern void __dma_sync(void *vaddr, size_t size, int direction);
  50 extern void __dma_sync_page(struct page *page, unsigned long offset,
  51                                  size_t size, int direction);
  52 extern unsigned long __dma_get_coherent_pfn(unsigned long cpu_addr);
  53
  54 #else /* ! CONFIG_NOT_COHERENT_CACHE */
  55 /*
  56  * Cache coherent cores.
  57  */
  58
  59 #define __dma_alloc_coherent(dev, gfp, size, handle)    NULL
  60 #define __dma_free_coherent(size, addr)         ((void)0)
  61 #define __dma_sync(addr, size, rw)              ((void)0)
  62 #define __dma_sync_page(pg, off, sz, rw)        ((void)0)
  63
  64 #endif /* ! CONFIG_NOT_COHERENT_CACHE */
  65
  66 static inline unsigned long device_to_mask(struct device *dev)
  67 {
  68         if (dev->dma_mask && *dev->dma_mask)
  69                 return *dev->dma_mask;
  70         /* Assume devices without mask can take 32 bit addresses */
  71         return 0xfffffffful;
  72 }
  73
  74 /*
  75  * Available generic sets of operations
  76  */
  77 #ifdef CONFIG_PPC64
  78 extern struct dma_map_ops dma_iommu_ops;
  79 #endif
  80 extern struct dma_map_ops dma_direct_ops;
  81
  82 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
  83 {
  84         /* We don't handle the NULL dev case for ISA for now. We could
  85          * do it via an out of line call but it is not needed for now. The
  86          * only ISA DMA device we support is the floppy and we have a hack
  87          * in the floppy driver directly to get a device for us.
  88          */
  89         if (unlikely(dev == NULL))
  90                 return NULL;
  91
  92         return dev->archdata.dma_ops;
  93 }
  94
  95 static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
  96 {
  97         dev->archdata.dma_ops = ops;
  98 }
  99
 100 /*
 101  * get_dma_offset()
 102  *
 103  * Get the dma offset on configurations where the dma address can be determined
 104  * from the physical address by looking at a simple offset.  Direct dma and
 105  * swiotlb use this function, but it is typically not used by implementations
 106  * with an iommu.
 107  */
 108 static inline dma_addr_t get_dma_offset(struct device *dev)
 109 {
 110         if (dev)
 111                 return dev->archdata.dma_offset;
 112
 113         return PCI_DRAM_OFFSET;
 114 }
 115
 116 static inline void set_dma_offset(struct device *dev, dma_addr_t off)
 117 {
 118         if (dev)
 119                 dev->archdata.dma_offset = off;
 120 }
 121
 122 /* this will be removed soon */
 123 #define flush_write_buffers()
 124
 125 #define HAVE_ARCH_DMA_SET_MASK 1
 126 extern int dma_set_mask(struct device *dev, u64 dma_mask);
 127
 128 #include <asm-generic/dma-mapping-common.h>
 129
 130 extern int __dma_set_mask(struct device *dev, u64 dma_mask);
 131 extern u64 __dma_get_required_mask(struct device *dev);
 132
 133 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 134 {
 135 #ifdef CONFIG_SWIOTLB
 136         struct dev_archdata *sd = &dev->archdata;
 137
 138         if (sd->max_direct_dma_addr && addr + size > sd->max_direct_dma_addr)
 139                 return false;
 140 #endif
 141
 142         if (!dev->dma_mask)
 143                 return false;
 144
 145         return addr + size - 1 <= *dev->dma_mask;
 146 }
 147
 148 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
 149 {
 150         return paddr + get_dma_offset(dev);
 151 }
 152
 153 static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
 154 {
 155         return daddr - get_dma_offset(dev);
 156 }
 157
 158 #define ARCH_HAS_DMA_MMAP_COHERENT
 159
 160 static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
 161                 enum dma_data_direction direction)
 162 {
 163         BUG_ON(direction == DMA_NONE);
 164         __dma_sync(vaddr, size, (int)direction);
 165 }
 166
 167 #endif /* __KERNEL__ */
 168 #endif  /* _ASM_DMA_MAPPING_H */