1 /*
2  * Implements the generic device dma API for microblaze and the pci
3  *
4  * Copyright (C) 2009-2010 Michal Simek <monstr@monstr.eu>
5  * Copyright (C) 2009-2010 PetaLogix
6  *
7  * This file is subject to the terms and conditions of the GNU General
8  * Public License. See the file COPYING in the main directory of this
9  * archive for more details.
10  *
11  * This file is base on powerpc and x86 dma-mapping.h versions
12  * Copyright (C) 2004 IBM
13  */
14 
15 #ifndef _ASM_MICROBLAZE_DMA_MAPPING_H
16 #define _ASM_MICROBLAZE_DMA_MAPPING_H
17 
18 /*
19  * See Documentation/DMA-API-HOWTO.txt and
20  * Documentation/DMA-API.txt for documentation.
21  */
22 
23 #include <linux/types.h>
24 #include <linux/cache.h>
25 #include <linux/mm.h>
26 #include <linux/scatterlist.h>
27 #include <linux/dma-debug.h>
28 #include <linux/dma-attrs.h>
29 #include <asm/io.h>
30 #include <asm-generic/dma-coherent.h>
31 #include <asm/cacheflush.h>
32 
33 #define DMA_ERROR_CODE		(~(dma_addr_t)0x0)
34 
35 #define __dma_alloc_coherent(dev, gfp, size, handle)	NULL
36 #define __dma_free_coherent(size, addr)		((void)0)
37 
device_to_mask(struct device * dev)38 static inline unsigned long device_to_mask(struct device *dev)
39 {
40 	if (dev->dma_mask && *dev->dma_mask)
41 		return *dev->dma_mask;
42 	/* Assume devices without mask can take 32 bit addresses */
43 	return 0xfffffffful;
44 }
45 
46 extern struct dma_map_ops *dma_ops;
47 
48 /*
49  * Available generic sets of operations
50  */
51 extern struct dma_map_ops dma_direct_ops;
52 
get_dma_ops(struct device * dev)53 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
54 {
55 	/* We don't handle the NULL dev case for ISA for now. We could
56 	 * do it via an out of line call but it is not needed for now. The
57 	 * only ISA DMA device we support is the floppy and we have a hack
58 	 * in the floppy driver directly to get a device for us.
59 	 */
60 	if (unlikely(!dev) || !dev->archdata.dma_ops)
61 		return NULL;
62 
63 	return dev->archdata.dma_ops;
64 }
65 
set_dma_ops(struct device * dev,struct dma_map_ops * ops)66 static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
67 {
68 	dev->archdata.dma_ops = ops;
69 }
70 
dma_supported(struct device * dev,u64 mask)71 static inline int dma_supported(struct device *dev, u64 mask)
72 {
73 	struct dma_map_ops *ops = get_dma_ops(dev);
74 
75 	if (unlikely(!ops))
76 		return 0;
77 	if (!ops->dma_supported)
78 		return 1;
79 	return ops->dma_supported(dev, mask);
80 }
81 
dma_set_mask(struct device * dev,u64 dma_mask)82 static inline int dma_set_mask(struct device *dev, u64 dma_mask)
83 {
84 	struct dma_map_ops *ops = get_dma_ops(dev);
85 
86 	if (unlikely(ops == NULL))
87 		return -EIO;
88 	if (ops->set_dma_mask)
89 		return ops->set_dma_mask(dev, dma_mask);
90 	if (!dev->dma_mask || !dma_supported(dev, dma_mask))
91 		return -EIO;
92 	*dev->dma_mask = dma_mask;
93 	return 0;
94 }
95 
96 #include <asm-generic/dma-mapping-common.h>
97 
__dma_sync(unsigned long paddr,size_t size,enum dma_data_direction direction)98 static inline void __dma_sync(unsigned long paddr,
99 			      size_t size, enum dma_data_direction direction)
100 {
101 	switch (direction) {
102 	case DMA_TO_DEVICE:
103 	case DMA_BIDIRECTIONAL:
104 		flush_dcache_range(paddr, paddr + size);
105 		break;
106 	case DMA_FROM_DEVICE:
107 		invalidate_dcache_range(paddr, paddr + size);
108 		break;
109 	default:
110 		BUG();
111 	}
112 }
113 
dma_mapping_error(struct device * dev,dma_addr_t dma_addr)114 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
115 {
116 	struct dma_map_ops *ops = get_dma_ops(dev);
117 	if (ops->mapping_error)
118 		return ops->mapping_error(dev, dma_addr);
119 
120 	return (dma_addr == DMA_ERROR_CODE);
121 }
122 
123 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
124 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
125 
126 #define dma_alloc_coherent(d, s, h, f) dma_alloc_attrs(d, s, h, f, NULL)
127 
dma_alloc_attrs(struct device * dev,size_t size,dma_addr_t * dma_handle,gfp_t flag,struct dma_attrs * attrs)128 static inline void *dma_alloc_attrs(struct device *dev, size_t size,
129 				    dma_addr_t *dma_handle, gfp_t flag,
130 				    struct dma_attrs *attrs)
131 {
132 	struct dma_map_ops *ops = get_dma_ops(dev);
133 	void *memory;
134 
135 	BUG_ON(!ops);
136 
137 	memory = ops->alloc(dev, size, dma_handle, flag, attrs);
138 
139 	debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
140 	return memory;
141 }
142 
143 #define dma_free_coherent(d,s,c,h) dma_free_attrs(d, s, c, h, NULL)
144 
dma_free_attrs(struct device * dev,size_t size,void * cpu_addr,dma_addr_t dma_handle,struct dma_attrs * attrs)145 static inline void dma_free_attrs(struct device *dev, size_t size,
146 				  void *cpu_addr, dma_addr_t dma_handle,
147 				  struct dma_attrs *attrs)
148 {
149 	struct dma_map_ops *ops = get_dma_ops(dev);
150 
151 	BUG_ON(!ops);
152 	debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
153 	ops->free(dev, size, cpu_addr, dma_handle, attrs);
154 }
155 
dma_cache_sync(struct device * dev,void * vaddr,size_t size,enum dma_data_direction direction)156 static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
157 		enum dma_data_direction direction)
158 {
159 	BUG_ON(direction == DMA_NONE);
160 	__dma_sync(virt_to_phys(vaddr), size, (int)direction);
161 }
162 
163 #endif	/* _ASM_MICROBLAZE_DMA_MAPPING_H */
164