linux/arch/powerpc/include/asm/dma-mapping.h
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   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 */
  24extern void *dma_direct_alloc_coherent(struct device *dev, size_t size,
  25                                       dma_addr_t *dma_handle, gfp_t flag,
  26                                       struct dma_attrs *attrs);
  27extern void dma_direct_free_coherent(struct device *dev, size_t size,
  28                                     void *vaddr, dma_addr_t dma_handle,
  29                                     struct dma_attrs *attrs);
  30
  31
  32#ifdef CONFIG_NOT_COHERENT_CACHE
  33/*
  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.
  39 */
  40struct device;
  41extern void *__dma_alloc_coherent(struct device *dev, size_t size,
  42                                  dma_addr_t *handle, gfp_t gfp);
  43extern void __dma_free_coherent(size_t size, void *vaddr);
  44extern void __dma_sync(void *vaddr, size_t size, int direction);
  45extern void __dma_sync_page(struct page *page, unsigned long offset,
  46                                 size_t size, int direction);
  47extern unsigned long __dma_get_coherent_pfn(unsigned long cpu_addr);
  48
  49#else /* ! CONFIG_NOT_COHERENT_CACHE */
  50/*
  51 * Cache coherent cores.
  52 */
  53
  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)
  58
  59#endif /* ! CONFIG_NOT_COHERENT_CACHE */
  60
  61static inline unsigned long device_to_mask(struct device *dev)
  62{
  63        if (dev->dma_mask && *dev->dma_mask)
  64                return *dev->dma_mask;
  65        /* Assume devices without mask can take 32 bit addresses */
  66        return 0xfffffffful;
  67}
  68
  69/*
  70 * Available generic sets of operations
  71 */
  72#ifdef CONFIG_PPC64
  73extern struct dma_map_ops dma_iommu_ops;
  74#endif
  75extern struct dma_map_ops dma_direct_ops;
  76
  77static inline struct dma_map_ops *get_dma_ops(struct device *dev)
  78{
  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.
  83         */
  84        if (unlikely(dev == NULL))
  85                return NULL;
  86
  87        return dev->archdata.dma_ops;
  88}
  89
  90static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
  91{
  92        dev->archdata.dma_ops = ops;
  93}
  94
  95/*
  96 * get_dma_offset()
  97 *
  98 * Get the dma offset on configurations where the dma address can be determined
  99 * from the physical address by looking at a simple offset.  Direct dma and
 100 * swiotlb use this function, but it is typically not used by implementations
 101 * with an iommu.
 102 */
 103static inline dma_addr_t get_dma_offset(struct device *dev)
 104{
 105        if (dev)
 106                return dev->archdata.dma_data.dma_offset;
 107
 108        return PCI_DRAM_OFFSET;
 109}
 110
 111static inline void set_dma_offset(struct device *dev, dma_addr_t off)
 112{
 113        if (dev)
 114                dev->archdata.dma_data.dma_offset = off;
 115}
 116
 117/* this will be removed soon */
 118#define flush_write_buffers()
 119
 120#include <asm-generic/dma-mapping-common.h>
 121
 122static inline int dma_supported(struct device *dev, u64 mask)
 123{
 124        struct dma_map_ops *dma_ops = get_dma_ops(dev);
 125
 126        if (unlikely(dma_ops == NULL))
 127                return 0;
 128        if (dma_ops->dma_supported == NULL)
 129                return 1;
 130        return dma_ops->dma_supported(dev, mask);
 131}
 132
 133extern int dma_set_mask(struct device *dev, u64 dma_mask);
 134
 135#define dma_alloc_coherent(d,s,h,f)     dma_alloc_attrs(d,s,h,f,NULL)
 136
 137static inline void *dma_alloc_attrs(struct device *dev, size_t size,
 138                                    dma_addr_t *dma_handle, gfp_t flag,
 139                                    struct dma_attrs *attrs)
 140{
 141        struct dma_map_ops *dma_ops = get_dma_ops(dev);
 142        void *cpu_addr;
 143
 144        BUG_ON(!dma_ops);
 145
 146        cpu_addr = dma_ops->alloc(dev, size, dma_handle, flag, attrs);
 147
 148        debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr);
 149
 150        return cpu_addr;
 151}
 152
 153#define dma_free_coherent(d,s,c,h) dma_free_attrs(d,s,c,h,NULL)
 154
 155static inline void dma_free_attrs(struct device *dev, size_t size,
 156                                  void *cpu_addr, dma_addr_t dma_handle,
 157                                  struct dma_attrs *attrs)
 158{
 159        struct dma_map_ops *dma_ops = get_dma_ops(dev);
 160
 161        BUG_ON(!dma_ops);
 162
 163        debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
 164
 165        dma_ops->free(dev, size, cpu_addr, dma_handle, attrs);
 166}
 167
 168static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 169{
 170        struct dma_map_ops *dma_ops = get_dma_ops(dev);
 171
 172        if (dma_ops->mapping_error)
 173                return dma_ops->mapping_error(dev, dma_addr);
 174
 175#ifdef CONFIG_PPC64
 176        return (dma_addr == DMA_ERROR_CODE);
 177#else
 178        return 0;
 179#endif
 180}
 181
 182static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 183{
 184#ifdef CONFIG_SWIOTLB
 185        struct dev_archdata *sd = &dev->archdata;
 186
 187        if (sd->max_direct_dma_addr && addr + size > sd->max_direct_dma_addr)
 188                return 0;
 189#endif
 190
 191        if (!dev->dma_mask)
 192                return 0;
 193
 194        return addr + size - 1 <= *dev->dma_mask;
 195}
 196
 197static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
 198{
 199        return paddr + get_dma_offset(dev);
 200}
 201
 202static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
 203{
 204        return daddr - get_dma_offset(dev);
 205}
 206
 207#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
 208#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
 209
 210extern int dma_mmap_coherent(struct device *, struct vm_area_struct *,
 211                             void *, dma_addr_t, size_t);
 212#define ARCH_HAS_DMA_MMAP_COHERENT
 213
 214
 215static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
 216                enum dma_data_direction direction)
 217{
 218        BUG_ON(direction == DMA_NONE);
 219        __dma_sync(vaddr, size, (int)direction);
 220}
 221
 222#endif /* __KERNEL__ */
 223#endif  /* _ASM_DMA_MAPPING_H */
 224