tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * CAAM/SEC 4.x functions for using scatterlists in caam driver
3 *
4 * Copyright 2008-2011 Freescale Semiconductor, Inc.
5 *
6 */
7
8struct sec4_sg_entry;
9
10/*
11 * convert single dma address to h/w link table format
12 */
13static inline void dma_to_sec4_sg_one(struct sec4_sg_entry *sec4_sg_ptr,
14 dma_addr_t dma, u32 len, u32 offset)
15{
16 sec4_sg_ptr->ptr = dma;
17 sec4_sg_ptr->len = len;
18 sec4_sg_ptr->reserved = 0;
19 sec4_sg_ptr->buf_pool_id = 0;
20 sec4_sg_ptr->offset = offset;
21#ifdef DEBUG
22 print_hex_dump(KERN_ERR, "sec4_sg_ptr@: ",
23 DUMP_PREFIX_ADDRESS, 16, 4, sec4_sg_ptr,
24 sizeof(struct sec4_sg_entry), 1);
25#endif
26}
27
28/*
29 * convert scatterlist to h/w link table format
30 * but does not have final bit; instead, returns last entry
31 */
32static inline struct sec4_sg_entry *
33sg_to_sec4_sg(struct scatterlist *sg, int sg_count,
34 struct sec4_sg_entry *sec4_sg_ptr, u32 offset)
35{
36 while (sg_count) {
37 dma_to_sec4_sg_one(sec4_sg_ptr, sg_dma_address(sg),
38 sg_dma_len(sg), offset);
39 sec4_sg_ptr++;
40 sg = sg_next(sg);
41 sg_count--;
42 }
43 return sec4_sg_ptr - 1;
44}
45
46/*
47 * convert scatterlist to h/w link table format
48 * scatterlist must have been previously dma mapped
49 */
50static inline void sg_to_sec4_sg_last(struct scatterlist *sg, int sg_count,
51 struct sec4_sg_entry *sec4_sg_ptr,
52 u32 offset)
53{
54 sec4_sg_ptr = sg_to_sec4_sg(sg, sg_count, sec4_sg_ptr, offset);
55 sec4_sg_ptr->len |= SEC4_SG_LEN_FIN;
56}
57
58static inline struct sec4_sg_entry *sg_to_sec4_sg_len(
59 struct scatterlist *sg, unsigned int total,
60 struct sec4_sg_entry *sec4_sg_ptr)
61{
62 do {
63 unsigned int len = min(sg_dma_len(sg), total);
64
65 dma_to_sec4_sg_one(sec4_sg_ptr, sg_dma_address(sg), len, 0);
66 sec4_sg_ptr++;
67 sg = sg_next(sg);
68 total -= len;
69 } while (total);
70 return sec4_sg_ptr - 1;
71}
72
73/* count number of elements in scatterlist */
74static inline int __sg_count(struct scatterlist *sg_list, int nbytes,
75 bool *chained)
76{
77 struct scatterlist *sg = sg_list;
78 int sg_nents = 0;
79
80 while (nbytes > 0) {
81 sg_nents++;
82 nbytes -= sg->length;
83 if (!sg_is_last(sg) && (sg + 1)->length == 0)
84 *chained = true;
85 sg = sg_next(sg);
86 }
87
88 return sg_nents;
89}
90
91/* derive number of elements in scatterlist, but return 0 for 1 */
92static inline int sg_count(struct scatterlist *sg_list, int nbytes,
93 bool *chained)
94{
95 int sg_nents = __sg_count(sg_list, nbytes, chained);
96
97 if (likely(sg_nents == 1))
98 return 0;
99
100 return sg_nents;
101}
102
103static inline void dma_unmap_sg_chained(
104 struct device *dev, struct scatterlist *sg, unsigned int nents,
105 enum dma_data_direction dir, bool chained)
106{
107 if (unlikely(chained)) {
108 int i;
109 for (i = 0; i < nents; i++) {
110 dma_unmap_sg(dev, sg, 1, dir);
111 sg = sg_next(sg);
112 }
113 } else if (nents) {
114 dma_unmap_sg(dev, sg, nents, dir);
115 }
116}
117
118static inline int dma_map_sg_chained(
119 struct device *dev, struct scatterlist *sg, unsigned int nents,
120 enum dma_data_direction dir, bool chained)
121{
122 struct scatterlist *first = sg;
123
124 if (unlikely(chained)) {
125 int i;
126 for (i = 0; i < nents; i++) {
127 if (!dma_map_sg(dev, sg, 1, dir)) {
128 dma_unmap_sg_chained(dev, first, i, dir,
129 chained);
130 nents = 0;
131 break;
132 }
133
134 sg = sg_next(sg);
135 }
136 } else
137 nents = dma_map_sg(dev, sg, nents, dir);
138
139 return nents;
140}