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 #define DMA_ERROR_CODE          (~(dma_addr_t)0x0)
  22
  23 /* Some dma direct funcs must be visible for use in other dma_ops */
  24 extern void *dma_direct_alloc_coherent(struct device *dev, size_t size,
  25                                        dma_addr_t *dma_handle, gfp_t flag);
  26 extern void dma_direct_free_coherent(struct device *dev, size_t size,
  27                                      void *vaddr, dma_addr_t dma_handle);
  28
  29
  30 #ifdef CONFIG_NOT_COHERENT_CACHE
  31 /*
  32  * DMA-consistent mapping functions for PowerPCs that don't support
  33  * cache snooping.  These allocate/free a region of uncached mapped
  34  * memory space for use with DMA devices.  Alternatively, you could
  35  * allocate the space "normally" and use the cache management functions
  36  * to ensure it is consistent.
  37  */
  38 struct device;
  39 extern void *__dma_alloc_coherent(struct device *dev, size_t size,
  40                                   dma_addr_t *handle, gfp_t gfp);
  41 extern void __dma_free_coherent(size_t size, void *vaddr);
  42 extern void __dma_sync(void *vaddr, size_t size, int direction);
  43 extern void __dma_sync_page(struct page *page, unsigned long offset,
  44                                  size_t size, int direction);
  45 extern unsigned long __dma_get_coherent_pfn(unsigned long cpu_addr);
  46
  47 #else /* ! CONFIG_NOT_COHERENT_CACHE */
  48 /*
  49  * Cache coherent cores.
  50  */
  51
  52 #define __dma_alloc_coherent(dev, gfp, size, handle)    NULL
  53 #define __dma_free_coherent(size, addr)         ((void)0)
  54 #define __dma_sync(addr, size, rw)              ((void)0)
  55 #define __dma_sync_page(pg, off, sz, rw)        ((void)0)
  56
  57 #endif /* ! CONFIG_NOT_COHERENT_CACHE */
  58
  59 static inline unsigned long device_to_mask(struct device *dev)
  60 {
  61         if (dev->dma_mask && *dev->dma_mask)
  62                 return *dev->dma_mask;
  63         /* Assume devices without mask can take 32 bit addresses */
  64         return 0xfffffffful;
  65 }
  66
  67 /*
  68  * Available generic sets of operations
  69  */
  70 #ifdef CONFIG_PPC64
  71 extern struct dma_map_ops dma_iommu_ops;
  72 #endif
  73 extern struct dma_map_ops dma_direct_ops;
  74
  75 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
  76 {
  77         /* We don't handle the NULL dev case for ISA for now. We could
  78          * do it via an out of line call but it is not needed for now. The
  79          * only ISA DMA device we support is the floppy and we have a hack
  80          * in the floppy driver directly to get a device for us.
  81          */
  82         if (unlikely(dev == NULL))
  83                 return NULL;
  84
  85         return dev->archdata.dma_ops;
  86 }
  87
  88 static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
  89 {
  90         dev->archdata.dma_ops = ops;
  91 }
  92
  93 /*
  94  * get_dma_offset()
  95  *
  96  * Get the dma offset on configurations where the dma address can be determined
  97  * from the physical address by looking at a simple offset.  Direct dma and
  98  * swiotlb use this function, but it is typically not used by implementations
  99  * with an iommu.
 100  */
 101 static inline dma_addr_t get_dma_offset(struct device *dev)
 102 {
 103         if (dev)
 104                 return dev->archdata.dma_data.dma_offset;
 105
 106         return PCI_DRAM_OFFSET;
 107 }
 108
 109 static inline void set_dma_offset(struct device *dev, dma_addr_t off)
 110 {
 111         if (dev)
 112                 dev->archdata.dma_data.dma_offset = off;
 113 }
 114
 115 /* this will be removed soon */
 116 #define flush_write_buffers()
 117
 118 #include <asm-generic/dma-mapping-common.h>
 119
 120 static inline int dma_supported(struct device *dev, u64 mask)
 121 {
 122         struct dma_map_ops *dma_ops = get_dma_ops(dev);
 123
 124         if (unlikely(dma_ops == NULL))
 125                 return 0;
 126         if (dma_ops->dma_supported == NULL)
 127                 return 1;
 128         return dma_ops->dma_supported(dev, mask);
 129 }
 130
 131 extern int dma_set_mask(struct device *dev, u64 dma_mask);
 132
 133 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
 134                                        dma_addr_t *dma_handle, gfp_t flag)
 135 {
 136         struct dma_map_ops *dma_ops = get_dma_ops(dev);
 137         void *cpu_addr;
 138
 139         BUG_ON(!dma_ops);
 140
 141         cpu_addr = dma_ops->alloc_coherent(dev, size, dma_handle, flag);
 142
 143         debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr);
 144
 145         return cpu_addr;
 146 }
 147
 148 static inline void dma_free_coherent(struct device *dev, size_t size,
 149                                      void *cpu_addr, dma_addr_t dma_handle)
 150 {
 151         struct dma_map_ops *dma_ops = get_dma_ops(dev);
 152
 153         BUG_ON(!dma_ops);
 154
 155         debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
 156
 157         dma_ops->free_coherent(dev, size, cpu_addr, dma_handle);
 158 }
 159
 160 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 161 {
 162         struct dma_map_ops *dma_ops = get_dma_ops(dev);
 163
 164         if (dma_ops->mapping_error)
 165                 return dma_ops->mapping_error(dev, dma_addr);
 166
 167 #ifdef CONFIG_PPC64
 168         return (dma_addr == DMA_ERROR_CODE);
 169 #else
 170         return 0;
 171 #endif
 172 }
 173
 174 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 175 {
 176 #ifdef CONFIG_SWIOTLB
 177         struct dev_archdata *sd = &dev->archdata;
 178
 179         if (sd->max_direct_dma_addr && addr + size > sd->max_direct_dma_addr)
 180                 return 0;
 181 #endif
 182
 183         if (!dev->dma_mask)
 184                 return 0;
 185
 186         return addr + size - 1 <= *dev->dma_mask;
 187 }
 188
 189 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
 190 {
 191         return paddr + get_dma_offset(dev);
 192 }
 193
 194 static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
 195 {
 196         return daddr - get_dma_offset(dev);
 197 }
 198
 199 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
 200 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
 201
 202 extern int dma_mmap_coherent(struct device *, struct vm_area_struct *,
 203                              void *, dma_addr_t, size_t);
 204 #define ARCH_HAS_DMA_MMAP_COHERENT
 205
 206
 207 static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
 208                 enum dma_data_direction direction)
 209 {
 210         BUG_ON(direction == DMA_NONE);
 211         __dma_sync(vaddr, size, (int)direction);
 212 }
 213
 214 #endif /* __KERNEL__ */
 215 #endif  /* _ASM_DMA_MAPPING_H */