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 if (dev) 62 pfn -= dev->dma_pfn_offset; 63 return (dma_addr_t)__pfn_to_bus(pfn); 64} 65 66static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr) 67{ 68 unsigned long pfn = __bus_to_pfn(addr); 69 70 if (dev) 71 pfn += dev->dma_pfn_offset; 72 73 return pfn; 74} 75 76static inline void *dma_to_virt(struct device *dev, dma_addr_t addr) 77{ 78 if (dev) { 79 unsigned long pfn = dma_to_pfn(dev, addr); 80 81 return phys_to_virt(__pfn_to_phys(pfn)); 82 } 83 84 return (void *)__bus_to_virt((unsigned long)addr); 85} 86 87static inline dma_addr_t virt_to_dma(struct device *dev, void *addr) 88{ 89 if (dev) 90 return pfn_to_dma(dev, virt_to_pfn(addr)); 91 92 return (dma_addr_t)__virt_to_bus((unsigned long)(addr)); 93} 94 95#else 96static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn) 97{ 98 return __arch_pfn_to_dma(dev, pfn); 99} 100 101static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr) 102{ 103 return __arch_dma_to_pfn(dev, addr); 104} 105 106static inline void *dma_to_virt(struct device *dev, dma_addr_t addr) 107{ 108 return __arch_dma_to_virt(dev, addr); 109} 110 111static inline dma_addr_t virt_to_dma(struct device *dev, void *addr) 112{ 113 return __arch_virt_to_dma(dev, addr); 114} 115#endif 116 117/* The ARM override for dma_max_pfn() */ 118static inline unsigned long dma_max_pfn(struct device *dev) 119{ 120 return PHYS_PFN_OFFSET + dma_to_pfn(dev, *dev->dma_mask); 121} 122#define dma_max_pfn(dev) dma_max_pfn(dev) 123 124#define arch_setup_dma_ops arch_setup_dma_ops 125extern void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, 126 struct iommu_ops *iommu, bool coherent); 127 128#define arch_teardown_dma_ops arch_teardown_dma_ops 129extern void arch_teardown_dma_ops(struct device *dev); 130 131/* do not use this function in a driver */ 132static inline bool is_device_dma_coherent(struct device *dev) 133{ 134 return dev->archdata.dma_coherent; 135} 136 137static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr) 138{ 139 unsigned int offset = paddr & ~PAGE_MASK; 140 return pfn_to_dma(dev, __phys_to_pfn(paddr)) + offset; 141} 142 143static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr) 144{ 145 unsigned int offset = dev_addr & ~PAGE_MASK; 146 return __pfn_to_phys(dma_to_pfn(dev, dev_addr)) + offset; 147} 148 149static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size) 150{ 151 u64 limit, mask; 152 153 if (!dev->dma_mask) 154 return 0; 155 156 mask = *dev->dma_mask; 157 158 limit = (mask + 1) & ~mask; 159 if (limit && size > limit) 160 return 0; 161 162 if ((addr | (addr + size - 1)) & ~mask) 163 return 0; 164 165 return 1; 166} 167 168static inline void dma_mark_clean(void *addr, size_t size) { } 169 170/* 171 * DMA errors are defined by all-bits-set in the DMA address. 172 */ 173static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr) 174{ 175 debug_dma_mapping_error(dev, dma_addr); 176 return dma_addr == DMA_ERROR_CODE; 177} 178 179/* 180 * Dummy noncoherent implementation. We don't provide a dma_cache_sync 181 * function so drivers using this API are highlighted with build warnings. 182 */ 183static inline void *dma_alloc_noncoherent(struct device *dev, size_t size, 184 dma_addr_t *handle, gfp_t gfp) 185{ 186 return NULL; 187} 188 189static inline void dma_free_noncoherent(struct device *dev, size_t size, 190 void *cpu_addr, dma_addr_t handle) 191{ 192} 193 194extern int dma_supported(struct device *dev, u64 mask); 195 196extern int arm_dma_set_mask(struct device *dev, u64 dma_mask); 197 198/** 199 * arm_dma_alloc - allocate consistent memory for DMA 200 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices 201 * @size: required memory size 202 * @handle: bus-specific DMA address 203 * @attrs: optinal attributes that specific mapping properties 204 * 205 * Allocate some memory for a device for performing DMA. This function 206 * allocates pages, and will return the CPU-viewed address, and sets @handle 207 * to be the device-viewed address. 208 */ 209extern void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, 210 gfp_t gfp, struct dma_attrs *attrs); 211 212#define dma_alloc_coherent(d, s, h, f) dma_alloc_attrs(d, s, h, f, NULL) 213 214static inline void *dma_alloc_attrs(struct device *dev, size_t size, 215 dma_addr_t *dma_handle, gfp_t flag, 216 struct dma_attrs *attrs) 217{ 218 struct dma_map_ops *ops = get_dma_ops(dev); 219 void *cpu_addr; 220 BUG_ON(!ops); 221 222 cpu_addr = ops->alloc(dev, size, dma_handle, flag, attrs); 223 debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr); 224 return cpu_addr; 225} 226 227/** 228 * arm_dma_free - free memory allocated by arm_dma_alloc 229 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices 230 * @size: size of memory originally requested in dma_alloc_coherent 231 * @cpu_addr: CPU-view address returned from dma_alloc_coherent 232 * @handle: device-view address returned from dma_alloc_coherent 233 * @attrs: optinal attributes that specific mapping properties 234 * 235 * Free (and unmap) a DMA buffer previously allocated by 236 * arm_dma_alloc(). 237 * 238 * References to memory and mappings associated with cpu_addr/handle 239 * during and after this call executing are illegal. 240 */ 241extern void arm_dma_free(struct device *dev, size_t size, void *cpu_addr, 242 dma_addr_t handle, struct dma_attrs *attrs); 243 244#define dma_free_coherent(d, s, c, h) dma_free_attrs(d, s, c, h, NULL) 245 246static inline void dma_free_attrs(struct device *dev, size_t size, 247 void *cpu_addr, dma_addr_t dma_handle, 248 struct dma_attrs *attrs) 249{ 250 struct dma_map_ops *ops = get_dma_ops(dev); 251 BUG_ON(!ops); 252 253 debug_dma_free_coherent(dev, size, cpu_addr, dma_handle); 254 ops->free(dev, size, cpu_addr, dma_handle, attrs); 255} 256 257/** 258 * arm_dma_mmap - map a coherent DMA allocation into user space 259 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices 260 * @vma: vm_area_struct describing requested user mapping 261 * @cpu_addr: kernel CPU-view address returned from dma_alloc_coherent 262 * @handle: device-view address returned from dma_alloc_coherent 263 * @size: size of memory originally requested in dma_alloc_coherent 264 * @attrs: optinal attributes that specific mapping properties 265 * 266 * Map a coherent DMA buffer previously allocated by dma_alloc_coherent 267 * into user space. The coherent DMA buffer must not be freed by the 268 * driver until the user space mapping has been released. 269 */ 270extern int arm_dma_mmap(struct device *dev, struct vm_area_struct *vma, 271 void *cpu_addr, dma_addr_t dma_addr, size_t size, 272 struct dma_attrs *attrs); 273 274/* 275 * This can be called during early boot to increase the size of the atomic 276 * coherent DMA pool above the default value of 256KiB. It must be called 277 * before postcore_initcall. 278 */ 279extern void __init init_dma_coherent_pool_size(unsigned long size); 280 281/* 282 * For SA-1111, IXP425, and ADI systems the dma-mapping functions are "magic" 283 * and utilize bounce buffers as needed to work around limited DMA windows. 284 * 285 * On the SA-1111, a bug limits DMA to only certain regions of RAM. 286 * On the IXP425, the PCI inbound window is 64MB (256MB total RAM) 287 * On some ADI engineering systems, PCI inbound window is 32MB (12MB total RAM) 288 * 289 * The following are helper functions used by the dmabounce subystem 290 * 291 */ 292 293/** 294 * dmabounce_register_dev 295 * 296 * @dev: valid struct device pointer 297 * @small_buf_size: size of buffers to use with small buffer pool 298 * @large_buf_size: size of buffers to use with large buffer pool (can be 0) 299 * @needs_bounce_fn: called to determine whether buffer needs bouncing 300 * 301 * This function should be called by low-level platform code to register 302 * a device as requireing DMA buffer bouncing. The function will allocate 303 * appropriate DMA pools for the device. 304 */ 305extern int dmabounce_register_dev(struct device *, unsigned long, 306 unsigned long, int (*)(struct device *, dma_addr_t, size_t)); 307 308/** 309 * dmabounce_unregister_dev 310 * 311 * @dev: valid struct device pointer 312 * 313 * This function should be called by low-level platform code when device 314 * that was previously registered with dmabounce_register_dev is removed 315 * from the system. 316 * 317 */ 318extern void dmabounce_unregister_dev(struct device *); 319 320 321 322/* 323 * The scatter list versions of the above methods. 324 */ 325extern int arm_dma_map_sg(struct device *, struct scatterlist *, int, 326 enum dma_data_direction, struct dma_attrs *attrs); 327extern void arm_dma_unmap_sg(struct device *, struct scatterlist *, int, 328 enum dma_data_direction, struct dma_attrs *attrs); 329extern void arm_dma_sync_sg_for_cpu(struct device *, struct scatterlist *, int, 330 enum dma_data_direction); 331extern void arm_dma_sync_sg_for_device(struct device *, struct scatterlist *, int, 332 enum dma_data_direction); 333extern int arm_dma_get_sgtable(struct device *dev, struct sg_table *sgt, 334 void *cpu_addr, dma_addr_t dma_addr, size_t size, 335 struct dma_attrs *attrs); 336 337#endif /* __KERNEL__ */ 338#endif 339