1 #ifndef ASMARM_DMA_MAPPING_H
2 #define ASMARM_DMA_MAPPING_H
6 #include <linux/mm_types.h>
7 #include <linux/scatterlist.h>
8 #include <linux/dma-debug.h>
10 #include <asm/memory.h>
13 #include <asm/xen/hypervisor.h>
15 extern const struct dma_map_ops arm_dma_ops;
16 extern const struct dma_map_ops arm_coherent_dma_ops;
18 static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
20 return IS_ENABLED(CONFIG_MMU) ? &arm_dma_ops : &dma_noop_ops;
23 #ifdef __arch_page_to_dma
24 #error Please update to __arch_pfn_to_dma
28 * dma_to_pfn/pfn_to_dma/dma_to_virt/virt_to_dma are architecture private
29 * functions used internally by the DMA-mapping API to provide DMA
30 * addresses. They must not be used by drivers.
32 #ifndef __arch_pfn_to_dma
33 static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
36 pfn -= dev->dma_pfn_offset;
37 return (dma_addr_t)__pfn_to_bus(pfn);
40 static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
42 unsigned long pfn = __bus_to_pfn(addr);
45 pfn += dev->dma_pfn_offset;
50 static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
53 unsigned long pfn = dma_to_pfn(dev, addr);
55 return phys_to_virt(__pfn_to_phys(pfn));
58 return (void *)__bus_to_virt((unsigned long)addr);
61 static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
64 return pfn_to_dma(dev, virt_to_pfn(addr));
66 return (dma_addr_t)__virt_to_bus((unsigned long)(addr));
70 static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
72 return __arch_pfn_to_dma(dev, pfn);
75 static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
77 return __arch_dma_to_pfn(dev, addr);
80 static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
82 return __arch_dma_to_virt(dev, addr);
85 static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
87 return __arch_virt_to_dma(dev, addr);
91 /* The ARM override for dma_max_pfn() */
92 static inline unsigned long dma_max_pfn(struct device *dev)
94 return dma_to_pfn(dev, *dev->dma_mask);
96 #define dma_max_pfn(dev) dma_max_pfn(dev)
98 #define arch_setup_dma_ops arch_setup_dma_ops
99 extern void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
100 const struct iommu_ops *iommu, bool coherent);
102 #define arch_teardown_dma_ops arch_teardown_dma_ops
103 extern void arch_teardown_dma_ops(struct device *dev);
105 /* do not use this function in a driver */
106 static inline bool is_device_dma_coherent(struct device *dev)
108 return dev->archdata.dma_coherent;
111 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
113 unsigned int offset = paddr & ~PAGE_MASK;
114 return pfn_to_dma(dev, __phys_to_pfn(paddr)) + offset;
117 static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
119 unsigned int offset = dev_addr & ~PAGE_MASK;
120 return __pfn_to_phys(dma_to_pfn(dev, dev_addr)) + offset;
123 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
130 mask = *dev->dma_mask;
132 limit = (mask + 1) & ~mask;
133 if (limit && size > limit)
136 if ((addr | (addr + size - 1)) & ~mask)
142 static inline void dma_mark_clean(void *addr, size_t size) { }
145 * arm_dma_alloc - allocate consistent memory for DMA
146 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
147 * @size: required memory size
148 * @handle: bus-specific DMA address
149 * @attrs: optinal attributes that specific mapping properties
151 * Allocate some memory for a device for performing DMA. This function
152 * allocates pages, and will return the CPU-viewed address, and sets @handle
153 * to be the device-viewed address.
155 extern void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
156 gfp_t gfp, unsigned long attrs);
159 * arm_dma_free - free memory allocated by arm_dma_alloc
160 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
161 * @size: size of memory originally requested in dma_alloc_coherent
162 * @cpu_addr: CPU-view address returned from dma_alloc_coherent
163 * @handle: device-view address returned from dma_alloc_coherent
164 * @attrs: optinal attributes that specific mapping properties
166 * Free (and unmap) a DMA buffer previously allocated by
169 * References to memory and mappings associated with cpu_addr/handle
170 * during and after this call executing are illegal.
172 extern void arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
173 dma_addr_t handle, unsigned long attrs);
176 * arm_dma_mmap - map a coherent DMA allocation into user space
177 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
178 * @vma: vm_area_struct describing requested user mapping
179 * @cpu_addr: kernel CPU-view address returned from dma_alloc_coherent
180 * @handle: device-view address returned from dma_alloc_coherent
181 * @size: size of memory originally requested in dma_alloc_coherent
182 * @attrs: optinal attributes that specific mapping properties
184 * Map a coherent DMA buffer previously allocated by dma_alloc_coherent
185 * into user space. The coherent DMA buffer must not be freed by the
186 * driver until the user space mapping has been released.
188 extern int arm_dma_mmap(struct device *dev, struct vm_area_struct *vma,
189 void *cpu_addr, dma_addr_t dma_addr, size_t size,
190 unsigned long attrs);
193 * This can be called during early boot to increase the size of the atomic
194 * coherent DMA pool above the default value of 256KiB. It must be called
195 * before postcore_initcall.
197 extern void __init init_dma_coherent_pool_size(unsigned long size);
200 * For SA-1111, IXP425, and ADI systems the dma-mapping functions are "magic"
201 * and utilize bounce buffers as needed to work around limited DMA windows.
203 * On the SA-1111, a bug limits DMA to only certain regions of RAM.
204 * On the IXP425, the PCI inbound window is 64MB (256MB total RAM)
205 * On some ADI engineering systems, PCI inbound window is 32MB (12MB total RAM)
207 * The following are helper functions used by the dmabounce subystem
212 * dmabounce_register_dev
214 * @dev: valid struct device pointer
215 * @small_buf_size: size of buffers to use with small buffer pool
216 * @large_buf_size: size of buffers to use with large buffer pool (can be 0)
217 * @needs_bounce_fn: called to determine whether buffer needs bouncing
219 * This function should be called by low-level platform code to register
220 * a device as requireing DMA buffer bouncing. The function will allocate
221 * appropriate DMA pools for the device.
223 extern int dmabounce_register_dev(struct device *, unsigned long,
224 unsigned long, int (*)(struct device *, dma_addr_t, size_t));
227 * dmabounce_unregister_dev
229 * @dev: valid struct device pointer
231 * This function should be called by low-level platform code when device
232 * that was previously registered with dmabounce_register_dev is removed
236 extern void dmabounce_unregister_dev(struct device *);
241 * The scatter list versions of the above methods.
243 extern int arm_dma_map_sg(struct device *, struct scatterlist *, int,
244 enum dma_data_direction, unsigned long attrs);
245 extern void arm_dma_unmap_sg(struct device *, struct scatterlist *, int,
246 enum dma_data_direction, unsigned long attrs);
247 extern void arm_dma_sync_sg_for_cpu(struct device *, struct scatterlist *, int,
248 enum dma_data_direction);
249 extern void arm_dma_sync_sg_for_device(struct device *, struct scatterlist *, int,
250 enum dma_data_direction);
251 extern int arm_dma_get_sgtable(struct device *dev, struct sg_table *sgt,
252 void *cpu_addr, dma_addr_t dma_addr, size_t size,
253 unsigned long attrs);
255 #endif /* __KERNEL__ */