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/memory.h>
 12
 13#include <xen/xen.h>
 14#include <asm/xen/hypervisor.h>
 15
 16#define DMA_ERROR_CODE	(~(dma_addr_t)0x0)
 17extern struct dma_map_ops arm_dma_ops;
 18extern struct dma_map_ops arm_coherent_dma_ops;
 19
 20static inline struct dma_map_ops *__generic_dma_ops(struct device *dev)
 21{
 22	if (dev && dev->archdata.dma_ops)
 23		return dev->archdata.dma_ops;
 24	return &arm_dma_ops;
 25}
 26
 27static inline struct dma_map_ops *get_dma_ops(struct device *dev)
 28{
 29	if (xen_initial_domain())
 30		return xen_dma_ops;
 31	else
 32		return __generic_dma_ops(dev);
 33}
 34
 35static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
 36{
 37	BUG_ON(!dev);
 38	dev->archdata.dma_ops = ops;
 39}
 40
 41#define HAVE_ARCH_DMA_SUPPORTED 1
 42extern int dma_supported(struct device *dev, u64 mask);
 43
 44#ifdef __arch_page_to_dma
 45#error Please update to __arch_pfn_to_dma
 46#endif
 47
 48/*
 49 * dma_to_pfn/pfn_to_dma/dma_to_virt/virt_to_dma are architecture private
 50 * functions used internally by the DMA-mapping API to provide DMA
 51 * addresses. They must not be used by drivers.
 52 */
 53#ifndef __arch_pfn_to_dma
 54static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
 55{
 56	if (dev)
 57		pfn -= dev->dma_pfn_offset;
 58	return (dma_addr_t)__pfn_to_bus(pfn);
 59}
 60
 61static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
 62{
 63	unsigned long pfn = __bus_to_pfn(addr);
 64
 65	if (dev)
 66		pfn += dev->dma_pfn_offset;
 67
 68	return pfn;
 69}
 70
 71static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
 72{
 73	if (dev) {
 74		unsigned long pfn = dma_to_pfn(dev, addr);
 75
 76		return phys_to_virt(__pfn_to_phys(pfn));
 77	}
 78
 79	return (void *)__bus_to_virt((unsigned long)addr);
 80}
 81
 82static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
 83{
 84	if (dev)
 85		return pfn_to_dma(dev, virt_to_pfn(addr));
 86
 87	return (dma_addr_t)__virt_to_bus((unsigned long)(addr));
 88}
 89
 90#else
 91static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
 92{
 93	return __arch_pfn_to_dma(dev, pfn);
 94}
 95
 96static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
 97{
 98	return __arch_dma_to_pfn(dev, addr);
 99}
100
101static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
102{
103	return __arch_dma_to_virt(dev, addr);
104}
105
106static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
107{
108	return __arch_virt_to_dma(dev, addr);
109}
110#endif
111
112/* The ARM override for dma_max_pfn() */
113static inline unsigned long dma_max_pfn(struct device *dev)
114{
115	return PHYS_PFN_OFFSET + dma_to_pfn(dev, *dev->dma_mask);
116}
117#define dma_max_pfn(dev) dma_max_pfn(dev)
118
119#define arch_setup_dma_ops arch_setup_dma_ops
120extern void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
121			       struct iommu_ops *iommu, bool coherent);
122
123#define arch_teardown_dma_ops arch_teardown_dma_ops
124extern void arch_teardown_dma_ops(struct device *dev);
125
126/* do not use this function in a driver */
127static inline bool is_device_dma_coherent(struct device *dev)
128{
129	return dev->archdata.dma_coherent;
130}
131
132static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
133{
134	unsigned int offset = paddr & ~PAGE_MASK;
135	return pfn_to_dma(dev, __phys_to_pfn(paddr)) + offset;
136}
137
138static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
139{
140	unsigned int offset = dev_addr & ~PAGE_MASK;
141	return __pfn_to_phys(dma_to_pfn(dev, dev_addr)) + offset;
142}
143
144static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
145{
146	u64 limit, mask;
147
148	if (!dev->dma_mask)
149		return 0;
150
151	mask = *dev->dma_mask;
152
153	limit = (mask + 1) & ~mask;
154	if (limit && size > limit)
155		return 0;
156
157	if ((addr | (addr + size - 1)) & ~mask)
158		return 0;
159
160	return 1;
161}
162
163static inline void dma_mark_clean(void *addr, size_t size) { }
164
165extern int arm_dma_set_mask(struct device *dev, u64 dma_mask);
166
167/**
168 * arm_dma_alloc - allocate consistent memory for DMA
169 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
170 * @size: required memory size
171 * @handle: bus-specific DMA address
172 * @attrs: optinal attributes that specific mapping properties
173 *
174 * Allocate some memory for a device for performing DMA.  This function
175 * allocates pages, and will return the CPU-viewed address, and sets @handle
176 * to be the device-viewed address.
177 */
178extern void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
179			   gfp_t gfp, struct dma_attrs *attrs);
180
181/**
182 * arm_dma_free - free memory allocated by arm_dma_alloc
183 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
184 * @size: size of memory originally requested in dma_alloc_coherent
185 * @cpu_addr: CPU-view address returned from dma_alloc_coherent
186 * @handle: device-view address returned from dma_alloc_coherent
187 * @attrs: optinal attributes that specific mapping properties
188 *
189 * Free (and unmap) a DMA buffer previously allocated by
190 * arm_dma_alloc().
191 *
192 * References to memory and mappings associated with cpu_addr/handle
193 * during and after this call executing are illegal.
194 */
195extern void arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
196			 dma_addr_t handle, struct dma_attrs *attrs);
197
198/**
199 * arm_dma_mmap - map a coherent DMA allocation into user space
200 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
201 * @vma: vm_area_struct describing requested user mapping
202 * @cpu_addr: kernel CPU-view address returned from dma_alloc_coherent
203 * @handle: device-view address returned from dma_alloc_coherent
204 * @size: size of memory originally requested in dma_alloc_coherent
205 * @attrs: optinal attributes that specific mapping properties
206 *
207 * Map a coherent DMA buffer previously allocated by dma_alloc_coherent
208 * into user space.  The coherent DMA buffer must not be freed by the
209 * driver until the user space mapping has been released.
210 */
211extern int arm_dma_mmap(struct device *dev, struct vm_area_struct *vma,
212			void *cpu_addr, dma_addr_t dma_addr, size_t size,
213			struct dma_attrs *attrs);
214
215/*
216 * This can be called during early boot to increase the size of the atomic
217 * coherent DMA pool above the default value of 256KiB. It must be called
218 * before postcore_initcall.
219 */
220extern void __init init_dma_coherent_pool_size(unsigned long size);
221
222/*
223 * For SA-1111, IXP425, and ADI systems  the dma-mapping functions are "magic"
224 * and utilize bounce buffers as needed to work around limited DMA windows.
225 *
226 * On the SA-1111, a bug limits DMA to only certain regions of RAM.
227 * On the IXP425, the PCI inbound window is 64MB (256MB total RAM)
228 * On some ADI engineering systems, PCI inbound window is 32MB (12MB total RAM)
229 *
230 * The following are helper functions used by the dmabounce subystem
231 *
232 */
233
234/**
235 * dmabounce_register_dev
236 *
237 * @dev: valid struct device pointer
238 * @small_buf_size: size of buffers to use with small buffer pool
239 * @large_buf_size: size of buffers to use with large buffer pool (can be 0)
240 * @needs_bounce_fn: called to determine whether buffer needs bouncing
241 *
242 * This function should be called by low-level platform code to register
243 * a device as requireing DMA buffer bouncing. The function will allocate
244 * appropriate DMA pools for the device.
245 */
246extern int dmabounce_register_dev(struct device *, unsigned long,
247		unsigned long, int (*)(struct device *, dma_addr_t, size_t));
248
249/**
250 * dmabounce_unregister_dev
251 *
252 * @dev: valid struct device pointer
253 *
254 * This function should be called by low-level platform code when device
255 * that was previously registered with dmabounce_register_dev is removed
256 * from the system.
257 *
258 */
259extern void dmabounce_unregister_dev(struct device *);
260
261
262
263/*
264 * The scatter list versions of the above methods.
265 */
266extern int arm_dma_map_sg(struct device *, struct scatterlist *, int,
267		enum dma_data_direction, struct dma_attrs *attrs);
268extern void arm_dma_unmap_sg(struct device *, struct scatterlist *, int,
269		enum dma_data_direction, struct dma_attrs *attrs);
270extern void arm_dma_sync_sg_for_cpu(struct device *, struct scatterlist *, int,
271		enum dma_data_direction);
272extern void arm_dma_sync_sg_for_device(struct device *, struct scatterlist *, int,
273		enum dma_data_direction);
274extern int arm_dma_get_sgtable(struct device *dev, struct sg_table *sgt,
275		void *cpu_addr, dma_addr_t dma_addr, size_t size,
276		struct dma_attrs *attrs);
277
278#endif /* __KERNEL__ */
279#endif