arch/arm/include/asm/dma-mapping.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef ASMARM_DMA_MAPPING_H
   3 #define ASMARM_DMA_MAPPING_H
   4
   5 #ifdef __KERNEL__
   6
   7 #include <linux/mm_types.h>
   8 #include <linux/scatterlist.h>
   9 #include <linux/dma-debug.h>
  10
  11 #include <asm/memory.h>
  12
  13 #include <xen/xen.h>
  14 #include <asm/xen/hypervisor.h>
  15
  16 extern const struct dma_map_ops arm_dma_ops;
  17 extern const struct dma_map_ops arm_coherent_dma_ops;
  18
  19 static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
  20 {
  21         return IS_ENABLED(CONFIG_MMU) ? &arm_dma_ops : &dma_noop_ops;
  22 }
  23
  24 #ifdef __arch_page_to_dma
  25 #error Please update to __arch_pfn_to_dma
  26 #endif
  27
  28 /*
  29  * dma_to_pfn/pfn_to_dma/dma_to_virt/virt_to_dma are architecture private
  30  * functions used internally by the DMA-mapping API to provide DMA
  31  * addresses. They must not be used by drivers.
  32  */
  33 #ifndef __arch_pfn_to_dma
  34 static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
  35 {
  36         if (dev)
  37                 pfn -= dev->dma_pfn_offset;
  38         return (dma_addr_t)__pfn_to_bus(pfn);
  39 }
  40
  41 static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
  42 {
  43         unsigned long pfn = __bus_to_pfn(addr);
  44
  45         if (dev)
  46                 pfn += dev->dma_pfn_offset;
  47
  48         return pfn;
  49 }
  50
  51 static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
  52 {
  53         if (dev) {
  54                 unsigned long pfn = dma_to_pfn(dev, addr);
  55
  56                 return phys_to_virt(__pfn_to_phys(pfn));
  57         }
  58
  59         return (void *)__bus_to_virt((unsigned long)addr);
  60 }
  61
  62 static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
  63 {
  64         if (dev)
  65                 return pfn_to_dma(dev, virt_to_pfn(addr));
  66
  67         return (dma_addr_t)__virt_to_bus((unsigned long)(addr));
  68 }
  69
  70 #else
  71 static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
  72 {
  73         return __arch_pfn_to_dma(dev, pfn);
  74 }
  75
  76 static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
  77 {
  78         return __arch_dma_to_pfn(dev, addr);
  79 }
  80
  81 static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
  82 {
  83         return __arch_dma_to_virt(dev, addr);
  84 }
  85
  86 static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
  87 {
  88         return __arch_virt_to_dma(dev, addr);
  89 }
  90 #endif
  91
  92 /* The ARM override for dma_max_pfn() */
  93 static inline unsigned long dma_max_pfn(struct device *dev)
  94 {
  95         return dma_to_pfn(dev, *dev->dma_mask);
  96 }
  97 #define dma_max_pfn(dev) dma_max_pfn(dev)
  98
  99 #define arch_setup_dma_ops arch_setup_dma_ops
 100 extern void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
 101                                const struct iommu_ops *iommu, bool coherent);
 102
 103 #define arch_teardown_dma_ops arch_teardown_dma_ops
 104 extern void arch_teardown_dma_ops(struct device *dev);
 105
 106 /* do not use this function in a driver */
 107 static inline bool is_device_dma_coherent(struct device *dev)
 108 {
 109         return dev->archdata.dma_coherent;
 110 }
 111
 112 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
 113 {
 114         unsigned int offset = paddr & ~PAGE_MASK;
 115         return pfn_to_dma(dev, __phys_to_pfn(paddr)) + offset;
 116 }
 117
 118 static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
 119 {
 120         unsigned int offset = dev_addr & ~PAGE_MASK;
 121         return __pfn_to_phys(dma_to_pfn(dev, dev_addr)) + offset;
 122 }
 123
 124 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 125 {
 126         u64 limit, mask;
 127
 128         if (!dev->dma_mask)
 129                 return 0;
 130
 131         mask = *dev->dma_mask;
 132
 133         limit = (mask + 1) & ~mask;
 134         if (limit && size > limit)
 135                 return 0;
 136
 137         if ((addr | (addr + size - 1)) & ~mask)
 138                 return 0;
 139
 140         return 1;
 141 }
 142
 143 static inline void dma_mark_clean(void *addr, size_t size) { }
 144
 145 /**
 146  * arm_dma_alloc - allocate consistent memory for DMA
 147  * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
 148  * @size: required memory size
 149  * @handle: bus-specific DMA address
 150  * @attrs: optinal attributes that specific mapping properties
 151  *
 152  * Allocate some memory for a device for performing DMA.  This function
 153  * allocates pages, and will return the CPU-viewed address, and sets @handle
 154  * to be the device-viewed address.
 155  */
 156 extern void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
 157                            gfp_t gfp, unsigned long attrs);
 158
 159 /**
 160  * arm_dma_free - free memory allocated by arm_dma_alloc
 161  * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
 162  * @size: size of memory originally requested in dma_alloc_coherent
 163  * @cpu_addr: CPU-view address returned from dma_alloc_coherent
 164  * @handle: device-view address returned from dma_alloc_coherent
 165  * @attrs: optinal attributes that specific mapping properties
 166  *
 167  * Free (and unmap) a DMA buffer previously allocated by
 168  * arm_dma_alloc().
 169  *
 170  * References to memory and mappings associated with cpu_addr/handle
 171  * during and after this call executing are illegal.
 172  */
 173 extern void arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
 174                          dma_addr_t handle, unsigned long attrs);
 175
 176 /**
 177  * arm_dma_mmap - map a coherent DMA allocation into user space
 178  * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
 179  * @vma: vm_area_struct describing requested user mapping
 180  * @cpu_addr: kernel CPU-view address returned from dma_alloc_coherent
 181  * @handle: device-view address returned from dma_alloc_coherent
 182  * @size: size of memory originally requested in dma_alloc_coherent
 183  * @attrs: optinal attributes that specific mapping properties
 184  *
 185  * Map a coherent DMA buffer previously allocated by dma_alloc_coherent
 186  * into user space.  The coherent DMA buffer must not be freed by the
 187  * driver until the user space mapping has been released.
 188  */
 189 extern int arm_dma_mmap(struct device *dev, struct vm_area_struct *vma,
 190                         void *cpu_addr, dma_addr_t dma_addr, size_t size,
 191                         unsigned long attrs);
 192
 193 /*
 194  * This can be called during early boot to increase the size of the atomic
 195  * coherent DMA pool above the default value of 256KiB. It must be called
 196  * before postcore_initcall.
 197  */
 198 extern void __init init_dma_coherent_pool_size(unsigned long size);
 199
 200 /*
 201  * For SA-1111, IXP425, and ADI systems  the dma-mapping functions are "magic"
 202  * and utilize bounce buffers as needed to work around limited DMA windows.
 203  *
 204  * On the SA-1111, a bug limits DMA to only certain regions of RAM.
 205  * On the IXP425, the PCI inbound window is 64MB (256MB total RAM)
 206  * On some ADI engineering systems, PCI inbound window is 32MB (12MB total RAM)
 207  *
 208  * The following are helper functions used by the dmabounce subystem
 209  *
 210  */
 211
 212 /**
 213  * dmabounce_register_dev
 214  *
 215  * @dev: valid struct device pointer
 216  * @small_buf_size: size of buffers to use with small buffer pool
 217  * @large_buf_size: size of buffers to use with large buffer pool (can be 0)
 218  * @needs_bounce_fn: called to determine whether buffer needs bouncing
 219  *
 220  * This function should be called by low-level platform code to register
 221  * a device as requireing DMA buffer bouncing. The function will allocate
 222  * appropriate DMA pools for the device.
 223  */
 224 extern int dmabounce_register_dev(struct device *, unsigned long,
 225                 unsigned long, int (*)(struct device *, dma_addr_t, size_t));
 226
 227 /**
 228  * dmabounce_unregister_dev
 229  *
 230  * @dev: valid struct device pointer
 231  *
 232  * This function should be called by low-level platform code when device
 233  * that was previously registered with dmabounce_register_dev is removed
 234  * from the system.
 235  *
 236  */
 237 extern void dmabounce_unregister_dev(struct device *);
 238
 239
 240
 241 /*
 242  * The scatter list versions of the above methods.
 243  */
 244 extern int arm_dma_map_sg(struct device *, struct scatterlist *, int,
 245                 enum dma_data_direction, unsigned long attrs);
 246 extern void arm_dma_unmap_sg(struct device *, struct scatterlist *, int,
 247                 enum dma_data_direction, unsigned long attrs);
 248 extern void arm_dma_sync_sg_for_cpu(struct device *, struct scatterlist *, int,
 249                 enum dma_data_direction);
 250 extern void arm_dma_sync_sg_for_device(struct device *, struct scatterlist *, int,
 251                 enum dma_data_direction);
 252 extern int arm_dma_get_sgtable(struct device *dev, struct sg_table *sgt,
 253                 void *cpu_addr, dma_addr_t dma_addr, size_t size,
 254                 unsigned long attrs);
 255
 256 #endif /* __KERNEL__ */
 257 #endif