linux/arch/arm/include/asm/dma-mapping.h
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   1#ifndef ASMARM_DMA_MAPPING_H
   2#define ASMARM_DMA_MAPPING_H
   3
   4#ifdef __KERNEL__
   5
   6#include <linux/mm_types.h>
   7#include <linux/scatterlist.h>
   8#include <linux/dma-attrs.h>
   9#include <linux/dma-debug.h>
  10
  11#include <asm-generic/dma-coherent.h>
  12#include <asm/memory.h>
  13
  14#include <xen/xen.h>
  15#include <asm/xen/hypervisor.h>
  16
  17#define DMA_ERROR_CODE  (~0)
  18extern struct dma_map_ops arm_dma_ops;
  19extern struct dma_map_ops arm_coherent_dma_ops;
  20
  21static inline struct dma_map_ops *__generic_dma_ops(struct device *dev)
  22{
  23        if (dev && dev->archdata.dma_ops)
  24                return dev->archdata.dma_ops;
  25        return &arm_dma_ops;
  26}
  27
  28static inline struct dma_map_ops *get_dma_ops(struct device *dev)
  29{
  30        if (xen_initial_domain())
  31                return xen_dma_ops;
  32        else
  33                return __generic_dma_ops(dev);
  34}
  35
  36static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
  37{
  38        BUG_ON(!dev);
  39        dev->archdata.dma_ops = ops;
  40}
  41
  42#include <asm-generic/dma-mapping-common.h>
  43
  44static inline int dma_set_mask(struct device *dev, u64 mask)
  45{
  46        return get_dma_ops(dev)->set_dma_mask(dev, mask);
  47}
  48
  49#ifdef __arch_page_to_dma
  50#error Please update to __arch_pfn_to_dma
  51#endif
  52
  53/*
  54 * dma_to_pfn/pfn_to_dma/dma_to_virt/virt_to_dma are architecture private
  55 * functions used internally by the DMA-mapping API to provide DMA
  56 * addresses. They must not be used by drivers.
  57 */
  58#ifndef __arch_pfn_to_dma
  59static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
  60{
  61        return (dma_addr_t)__pfn_to_bus(pfn);
  62}
  63
  64static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
  65{
  66        return __bus_to_pfn(addr);
  67}
  68
  69static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
  70{
  71        return (void *)__bus_to_virt((unsigned long)addr);
  72}
  73
  74static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
  75{
  76        return (dma_addr_t)__virt_to_bus((unsigned long)(addr));
  77}
  78
  79#else
  80static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
  81{
  82        return __arch_pfn_to_dma(dev, pfn);
  83}
  84
  85static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
  86{
  87        return __arch_dma_to_pfn(dev, addr);
  88}
  89
  90static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
  91{
  92        return __arch_dma_to_virt(dev, addr);
  93}
  94
  95static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
  96{
  97        return __arch_virt_to_dma(dev, addr);
  98}
  99#endif
 100
 101/* The ARM override for dma_max_pfn() */
 102static inline unsigned long dma_max_pfn(struct device *dev)
 103{
 104        return PHYS_PFN_OFFSET + dma_to_pfn(dev, *dev->dma_mask);
 105}
 106#define dma_max_pfn(dev) dma_max_pfn(dev)
 107
 108static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
 109{
 110        unsigned int offset = paddr & ~PAGE_MASK;
 111        return pfn_to_dma(dev, __phys_to_pfn(paddr)) + offset;
 112}
 113
 114static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
 115{
 116        unsigned int offset = dev_addr & ~PAGE_MASK;
 117        return __pfn_to_phys(dma_to_pfn(dev, dev_addr)) + offset;
 118}
 119
 120static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 121{
 122        u64 limit, mask;
 123
 124        if (!dev->dma_mask)
 125                return 0;
 126
 127        mask = *dev->dma_mask;
 128
 129        limit = (mask + 1) & ~mask;
 130        if (limit && size > limit)
 131                return 0;
 132
 133        if ((addr | (addr + size - 1)) & ~mask)
 134                return 0;
 135
 136        return 1;
 137}
 138
 139static inline void dma_mark_clean(void *addr, size_t size) { }
 140
 141/*
 142 * DMA errors are defined by all-bits-set in the DMA address.
 143 */
 144static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 145{
 146        debug_dma_mapping_error(dev, dma_addr);
 147        return dma_addr == DMA_ERROR_CODE;
 148}
 149
 150/*
 151 * Dummy noncoherent implementation.  We don't provide a dma_cache_sync
 152 * function so drivers using this API are highlighted with build warnings.
 153 */
 154static inline void *dma_alloc_noncoherent(struct device *dev, size_t size,
 155                dma_addr_t *handle, gfp_t gfp)
 156{
 157        return NULL;
 158}
 159
 160static inline void dma_free_noncoherent(struct device *dev, size_t size,
 161                void *cpu_addr, dma_addr_t handle)
 162{
 163}
 164
 165extern int dma_supported(struct device *dev, u64 mask);
 166
 167extern int arm_dma_set_mask(struct device *dev, u64 dma_mask);
 168
 169/**
 170 * arm_dma_alloc - allocate consistent memory for DMA
 171 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
 172 * @size: required memory size
 173 * @handle: bus-specific DMA address
 174 * @attrs: optinal attributes that specific mapping properties
 175 *
 176 * Allocate some memory for a device for performing DMA.  This function
 177 * allocates pages, and will return the CPU-viewed address, and sets @handle
 178 * to be the device-viewed address.
 179 */
 180extern void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
 181                           gfp_t gfp, struct dma_attrs *attrs);
 182
 183#define dma_alloc_coherent(d, s, h, f) dma_alloc_attrs(d, s, h, f, NULL)
 184
 185static inline void *dma_alloc_attrs(struct device *dev, size_t size,
 186                                       dma_addr_t *dma_handle, gfp_t flag,
 187                                       struct dma_attrs *attrs)
 188{
 189        struct dma_map_ops *ops = get_dma_ops(dev);
 190        void *cpu_addr;
 191        BUG_ON(!ops);
 192
 193        cpu_addr = ops->alloc(dev, size, dma_handle, flag, attrs);
 194        debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr);
 195        return cpu_addr;
 196}
 197
 198/**
 199 * arm_dma_free - free memory allocated by arm_dma_alloc
 200 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
 201 * @size: size of memory originally requested in dma_alloc_coherent
 202 * @cpu_addr: CPU-view address returned from dma_alloc_coherent
 203 * @handle: device-view address returned from dma_alloc_coherent
 204 * @attrs: optinal attributes that specific mapping properties
 205 *
 206 * Free (and unmap) a DMA buffer previously allocated by
 207 * arm_dma_alloc().
 208 *
 209 * References to memory and mappings associated with cpu_addr/handle
 210 * during and after this call executing are illegal.
 211 */
 212extern void arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
 213                         dma_addr_t handle, struct dma_attrs *attrs);
 214
 215#define dma_free_coherent(d, s, c, h) dma_free_attrs(d, s, c, h, NULL)
 216
 217static inline void dma_free_attrs(struct device *dev, size_t size,
 218                                     void *cpu_addr, dma_addr_t dma_handle,
 219                                     struct dma_attrs *attrs)
 220{
 221        struct dma_map_ops *ops = get_dma_ops(dev);
 222        BUG_ON(!ops);
 223
 224        debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
 225        ops->free(dev, size, cpu_addr, dma_handle, attrs);
 226}
 227
 228/**
 229 * arm_dma_mmap - map a coherent DMA allocation into user space
 230 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
 231 * @vma: vm_area_struct describing requested user mapping
 232 * @cpu_addr: kernel CPU-view address returned from dma_alloc_coherent
 233 * @handle: device-view address returned from dma_alloc_coherent
 234 * @size: size of memory originally requested in dma_alloc_coherent
 235 * @attrs: optinal attributes that specific mapping properties
 236 *
 237 * Map a coherent DMA buffer previously allocated by dma_alloc_coherent
 238 * into user space.  The coherent DMA buffer must not be freed by the
 239 * driver until the user space mapping has been released.
 240 */
 241extern int arm_dma_mmap(struct device *dev, struct vm_area_struct *vma,
 242                        void *cpu_addr, dma_addr_t dma_addr, size_t size,
 243                        struct dma_attrs *attrs);
 244
 245static inline void *dma_alloc_writecombine(struct device *dev, size_t size,
 246                                       dma_addr_t *dma_handle, gfp_t flag)
 247{
 248        DEFINE_DMA_ATTRS(attrs);
 249        dma_set_attr(DMA_ATTR_WRITE_COMBINE, &attrs);
 250        return dma_alloc_attrs(dev, size, dma_handle, flag, &attrs);
 251}
 252
 253static inline void dma_free_writecombine(struct device *dev, size_t size,
 254                                     void *cpu_addr, dma_addr_t dma_handle)
 255{
 256        DEFINE_DMA_ATTRS(attrs);
 257        dma_set_attr(DMA_ATTR_WRITE_COMBINE, &attrs);
 258        return dma_free_attrs(dev, size, cpu_addr, dma_handle, &attrs);
 259}
 260
 261/*
 262 * This can be called during early boot to increase the size of the atomic
 263 * coherent DMA pool above the default value of 256KiB. It must be called
 264 * before postcore_initcall.
 265 */
 266extern void __init init_dma_coherent_pool_size(unsigned long size);
 267
 268/*
 269 * For SA-1111, IXP425, and ADI systems  the dma-mapping functions are "magic"
 270 * and utilize bounce buffers as needed to work around limited DMA windows.
 271 *
 272 * On the SA-1111, a bug limits DMA to only certain regions of RAM.
 273 * On the IXP425, the PCI inbound window is 64MB (256MB total RAM)
 274 * On some ADI engineering systems, PCI inbound window is 32MB (12MB total RAM)
 275 *
 276 * The following are helper functions used by the dmabounce subystem
 277 *
 278 */
 279
 280/**
 281 * dmabounce_register_dev
 282 *
 283 * @dev: valid struct device pointer
 284 * @small_buf_size: size of buffers to use with small buffer pool
 285 * @large_buf_size: size of buffers to use with large buffer pool (can be 0)
 286 * @needs_bounce_fn: called to determine whether buffer needs bouncing
 287 *
 288 * This function should be called by low-level platform code to register
 289 * a device as requireing DMA buffer bouncing. The function will allocate
 290 * appropriate DMA pools for the device.
 291 */
 292extern int dmabounce_register_dev(struct device *, unsigned long,
 293                unsigned long, int (*)(struct device *, dma_addr_t, size_t));
 294
 295/**
 296 * dmabounce_unregister_dev
 297 *
 298 * @dev: valid struct device pointer
 299 *
 300 * This function should be called by low-level platform code when device
 301 * that was previously registered with dmabounce_register_dev is removed
 302 * from the system.
 303 *
 304 */
 305extern void dmabounce_unregister_dev(struct device *);
 306
 307
 308
 309/*
 310 * The scatter list versions of the above methods.
 311 */
 312extern int arm_dma_map_sg(struct device *, struct scatterlist *, int,
 313                enum dma_data_direction, struct dma_attrs *attrs);
 314extern void arm_dma_unmap_sg(struct device *, struct scatterlist *, int,
 315                enum dma_data_direction, struct dma_attrs *attrs);
 316extern void arm_dma_sync_sg_for_cpu(struct device *, struct scatterlist *, int,
 317                enum dma_data_direction);
 318extern void arm_dma_sync_sg_for_device(struct device *, struct scatterlist *, int,
 319                enum dma_data_direction);
 320extern int arm_dma_get_sgtable(struct device *dev, struct sg_table *sgt,
 321                void *cpu_addr, dma_addr_t dma_addr, size_t size,
 322                struct dma_attrs *attrs);
 323
 324#endif /* __KERNEL__ */
 325#endif
 326