release/src-rt-6.x.4708/linux/linux-2.6.36/arch/microblaze/include/asm/dma-mapping.h

   1 /*
   2  * Implements the generic device dma API for microblaze and the pci
   3  *
   4  * Copyright (C) 2009-2010 Michal Simek <monstr@monstr.eu>
   5  * Copyright (C) 2009-2010 PetaLogix
   6  *
   7  * This file is subject to the terms and conditions of the GNU General
   8  * Public License. See the file COPYING in the main directory of this
   9  * archive for more details.
  10  *
  11  * This file is base on powerpc and x86 dma-mapping.h versions
  12  * Copyright (C) 2004 IBM
  13  */
  14
  15 #ifndef _ASM_MICROBLAZE_DMA_MAPPING_H
  16 #define _ASM_MICROBLAZE_DMA_MAPPING_H
  17
  18 /*
  19  * See Documentation/PCI/PCI-DMA-mapping.txt and
  20  * Documentation/DMA-API.txt for documentation.
  21  */
  22
  23 #include <linux/types.h>
  24 #include <linux/cache.h>
  25 #include <linux/mm.h>
  26 #include <linux/scatterlist.h>
  27 #include <linux/dma-debug.h>
  28 #include <linux/dma-attrs.h>
  29 #include <asm/io.h>
  30 #include <asm-generic/dma-coherent.h>
  31
  32 #define DMA_ERROR_CODE          (~(dma_addr_t)0x0)
  33
  34 #define __dma_alloc_coherent(dev, gfp, size, handle)    NULL
  35 #define __dma_free_coherent(size, addr)         ((void)0)
  36 #define __dma_sync(addr, size, rw)              ((void)0)
  37
  38 static inline unsigned long device_to_mask(struct device *dev)
  39 {
  40         if (dev->dma_mask && *dev->dma_mask)
  41                 return *dev->dma_mask;
  42         /* Assume devices without mask can take 32 bit addresses */
  43         return 0xfffffffful;
  44 }
  45
  46 extern struct dma_map_ops *dma_ops;
  47
  48 /*
  49  * Available generic sets of operations
  50  */
  51 extern struct dma_map_ops dma_direct_ops;
  52
  53 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
  54 {
  55         /* We don't handle the NULL dev case for ISA for now. We could
  56          * do it via an out of line call but it is not needed for now. The
  57          * only ISA DMA device we support is the floppy and we have a hack
  58          * in the floppy driver directly to get a device for us.
  59          */
  60         if (unlikely(!dev) || !dev->archdata.dma_ops)
  61                 return NULL;
  62
  63         return dev->archdata.dma_ops;
  64 }
  65
  66 static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
  67 {
  68         dev->archdata.dma_ops = ops;
  69 }
  70
  71 static inline int dma_supported(struct device *dev, u64 mask)
  72 {
  73         struct dma_map_ops *ops = get_dma_ops(dev);
  74
  75         if (unlikely(!ops))
  76                 return 0;
  77         if (!ops->dma_supported)
  78                 return 1;
  79         return ops->dma_supported(dev, mask);
  80 }
  81
  82 static inline int dma_set_mask(struct device *dev, u64 dma_mask)
  83 {
  84         struct dma_map_ops *ops = get_dma_ops(dev);
  85
  86         if (unlikely(ops == NULL))
  87                 return -EIO;
  88         if (ops->set_dma_mask)
  89                 return ops->set_dma_mask(dev, dma_mask);
  90         if (!dev->dma_mask || !dma_supported(dev, dma_mask))
  91                 return -EIO;
  92         *dev->dma_mask = dma_mask;
  93         return 0;
  94 }
  95
  96 #include <asm-generic/dma-mapping-common.h>
  97
  98 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
  99 {
 100         struct dma_map_ops *ops = get_dma_ops(dev);
 101         if (ops->mapping_error)
 102                 return ops->mapping_error(dev, dma_addr);
 103
 104         return (dma_addr == DMA_ERROR_CODE);
 105 }
 106
 107 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
 108 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
 109
 110 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
 111                                         dma_addr_t *dma_handle, gfp_t flag)
 112 {
 113         struct dma_map_ops *ops = get_dma_ops(dev);
 114         void *memory;
 115
 116         BUG_ON(!ops);
 117
 118         memory = ops->alloc_coherent(dev, size, dma_handle, flag);
 119
 120         debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
 121         return memory;
 122 }
 123
 124 static inline void dma_free_coherent(struct device *dev, size_t size,
 125                                      void *cpu_addr, dma_addr_t dma_handle)
 126 {
 127         struct dma_map_ops *ops = get_dma_ops(dev);
 128
 129         BUG_ON(!ops);
 130         debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
 131         ops->free_coherent(dev, size, cpu_addr, dma_handle);
 132 }
 133
 134 static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
 135                 enum dma_data_direction direction)
 136 {
 137         BUG_ON(direction == DMA_NONE);
 138         __dma_sync(vaddr, size, (int)direction);
 139 }
 140
 141 #endif  /* _ASM_MICROBLAZE_DMA_MAPPING_H */