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-debug.h>
  9
 10#include <asm/memory.h>
 11
 12#include <xen/xen.h>
 13#include <asm/xen/hypervisor.h>
 14
 15#define DMA_ERROR_CODE	(~(dma_addr_t)0x0)
 16extern struct dma_map_ops arm_dma_ops;
 17extern struct dma_map_ops arm_coherent_dma_ops;
 18
 19static inline struct dma_map_ops *__generic_dma_ops(struct device *dev)
 20{
 21	if (dev && dev->archdata.dma_ops)
 22		return dev->archdata.dma_ops;
 23	return &arm_dma_ops;
 24}
 25
 26static inline struct dma_map_ops *get_dma_ops(struct device *dev)
 27{
 28	if (xen_initial_domain())
 29		return xen_dma_ops;
 30	else
 31		return __generic_dma_ops(dev);
 32}
 33
 34static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
 35{
 36	BUG_ON(!dev);
 37	dev->archdata.dma_ops = ops;
 38}
 39
 40#define HAVE_ARCH_DMA_SUPPORTED 1
 41extern int dma_supported(struct device *dev, u64 mask);
 42
 43#ifdef __arch_page_to_dma
 44#error Please update to __arch_pfn_to_dma
 45#endif
 46
 47/*
 48 * dma_to_pfn/pfn_to_dma/dma_to_virt/virt_to_dma are architecture private
 49 * functions used internally by the DMA-mapping API to provide DMA
 50 * addresses. They must not be used by drivers.
 51 */
 52#ifndef __arch_pfn_to_dma
 53static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
 54{
 55	if (dev)
 56		pfn -= dev->dma_pfn_offset;
 57	return (dma_addr_t)__pfn_to_bus(pfn);
 58}
 59
 60static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
 61{
 62	unsigned long pfn = __bus_to_pfn(addr);
 63
 64	if (dev)
 65		pfn += dev->dma_pfn_offset;
 66
 67	return pfn;
 68}
 69
 70static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
 71{
 72	if (dev) {
 73		unsigned long pfn = dma_to_pfn(dev, addr);
 74
 75		return phys_to_virt(__pfn_to_phys(pfn));
 76	}
 77
 78	return (void *)__bus_to_virt((unsigned long)addr);
 79}
 80
 81static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
 82{
 83	if (dev)
 84		return pfn_to_dma(dev, virt_to_pfn(addr));
 85
 86	return (dma_addr_t)__virt_to_bus((unsigned long)(addr));
 87}
 88
 89#else
 90static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
 91{
 92	return __arch_pfn_to_dma(dev, pfn);
 93}
 94
 95static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
 96{
 97	return __arch_dma_to_pfn(dev, addr);
 98}
 99
100static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
101{
102	return __arch_dma_to_virt(dev, addr);
103}
104
105static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
106{
107	return __arch_virt_to_dma(dev, addr);
108}
109#endif
110
111/* The ARM override for dma_max_pfn() */
112static inline unsigned long dma_max_pfn(struct device *dev)
113{
114	return dma_to_pfn(dev, *dev->dma_mask);
115}
116#define dma_max_pfn(dev) dma_max_pfn(dev)
117
118#define arch_setup_dma_ops arch_setup_dma_ops
119extern void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
120			       const struct iommu_ops *iommu, bool coherent);
121
122#define arch_teardown_dma_ops arch_teardown_dma_ops
123extern void arch_teardown_dma_ops(struct device *dev);
124
125/* do not use this function in a driver */
126static inline bool is_device_dma_coherent(struct device *dev)
127{
128	return dev->archdata.dma_coherent;
129}
130
131static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
132{
133	unsigned int offset = paddr & ~PAGE_MASK;
134	return pfn_to_dma(dev, __phys_to_pfn(paddr)) + offset;
135}
136
137static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
138{
139	unsigned int offset = dev_addr & ~PAGE_MASK;
140	return __pfn_to_phys(dma_to_pfn(dev, dev_addr)) + offset;
141}
142
143static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
144{
145	u64 limit, mask;
146
147	if (!dev->dma_mask)
148		return 0;
149
150	mask = *dev->dma_mask;
151
152	limit = (mask + 1) & ~mask;
153	if (limit && size > limit)
154		return 0;
155
156	if ((addr | (addr + size - 1)) & ~mask)
157		return 0;
158
159	return 1;
160}
161
162static inline void dma_mark_clean(void *addr, size_t size) { }
163
164/**
165 * arm_dma_alloc - allocate consistent memory for DMA
166 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
167 * @size: required memory size
168 * @handle: bus-specific DMA address
169 * @attrs: optinal attributes that specific mapping properties
170 *
171 * Allocate some memory for a device for performing DMA.  This function
172 * allocates pages, and will return the CPU-viewed address, and sets @handle
173 * to be the device-viewed address.
174 */
175extern void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
176			   gfp_t gfp, unsigned long attrs);
177
178/**
179 * arm_dma_free - free memory allocated by arm_dma_alloc
180 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
181 * @size: size of memory originally requested in dma_alloc_coherent
182 * @cpu_addr: CPU-view address returned from dma_alloc_coherent
183 * @handle: device-view address returned from dma_alloc_coherent
184 * @attrs: optinal attributes that specific mapping properties
185 *
186 * Free (and unmap) a DMA buffer previously allocated by
187 * arm_dma_alloc().
188 *
189 * References to memory and mappings associated with cpu_addr/handle
190 * during and after this call executing are illegal.
191 */
192extern void arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
193			 dma_addr_t handle, unsigned long attrs);
194
195/**
196 * arm_dma_mmap - map a coherent DMA allocation into user space
197 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
198 * @vma: vm_area_struct describing requested user mapping
199 * @cpu_addr: kernel CPU-view address returned from dma_alloc_coherent
200 * @handle: device-view address returned from dma_alloc_coherent
201 * @size: size of memory originally requested in dma_alloc_coherent
202 * @attrs: optinal attributes that specific mapping properties
203 *
204 * Map a coherent DMA buffer previously allocated by dma_alloc_coherent
205 * into user space.  The coherent DMA buffer must not be freed by the
206 * driver until the user space mapping has been released.
207 */
208extern int arm_dma_mmap(struct device *dev, struct vm_area_struct *vma,
209			void *cpu_addr, dma_addr_t dma_addr, size_t size,
210			unsigned long attrs);
211
212/*
213 * This can be called during early boot to increase the size of the atomic
214 * coherent DMA pool above the default value of 256KiB. It must be called
215 * before postcore_initcall.
216 */
217extern void __init init_dma_coherent_pool_size(unsigned long size);
218
219/*
220 * For SA-1111, IXP425, and ADI systems  the dma-mapping functions are "magic"
221 * and utilize bounce buffers as needed to work around limited DMA windows.
222 *
223 * On the SA-1111, a bug limits DMA to only certain regions of RAM.
224 * On the IXP425, the PCI inbound window is 64MB (256MB total RAM)
225 * On some ADI engineering systems, PCI inbound window is 32MB (12MB total RAM)
226 *
227 * The following are helper functions used by the dmabounce subystem
228 *
229 */
230
231/**
232 * dmabounce_register_dev
233 *
234 * @dev: valid struct device pointer
235 * @small_buf_size: size of buffers to use with small buffer pool
236 * @large_buf_size: size of buffers to use with large buffer pool (can be 0)
237 * @needs_bounce_fn: called to determine whether buffer needs bouncing
238 *
239 * This function should be called by low-level platform code to register
240 * a device as requireing DMA buffer bouncing. The function will allocate
241 * appropriate DMA pools for the device.
242 */
243extern int dmabounce_register_dev(struct device *, unsigned long,
244		unsigned long, int (*)(struct device *, dma_addr_t, size_t));
245
246/**
247 * dmabounce_unregister_dev
248 *
249 * @dev: valid struct device pointer
250 *
251 * This function should be called by low-level platform code when device
252 * that was previously registered with dmabounce_register_dev is removed
253 * from the system.
254 *
255 */
256extern void dmabounce_unregister_dev(struct device *);
257
258
259
260/*
261 * The scatter list versions of the above methods.
262 */
263extern int arm_dma_map_sg(struct device *, struct scatterlist *, int,
264		enum dma_data_direction, unsigned long attrs);
265extern void arm_dma_unmap_sg(struct device *, struct scatterlist *, int,
266		enum dma_data_direction, unsigned long attrs);
267extern void arm_dma_sync_sg_for_cpu(struct device *, struct scatterlist *, int,
268		enum dma_data_direction);
269extern void arm_dma_sync_sg_for_device(struct device *, struct scatterlist *, int,
270		enum dma_data_direction);
271extern int arm_dma_get_sgtable(struct device *dev, struct sg_table *sgt,
272		void *cpu_addr, dma_addr_t dma_addr, size_t size,
273		unsigned long attrs);
274
275#endif /* __KERNEL__ */
276#endif