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
58/* count number of elements in scatterlist */
59static inline int __sg_count(struct scatterlist *sg_list, int nbytes,
60			     bool *chained)
61{
62	struct scatterlist *sg = sg_list;
63	int sg_nents = 0;
64
65	while (nbytes > 0) {
66		sg_nents++;
67		nbytes -= sg->length;
68		if (!sg_is_last(sg) && (sg + 1)->length == 0)
69			*chained = true;
70		sg = sg_next(sg);
71	}
72
73	return sg_nents;
74}
75
76/* derive number of elements in scatterlist, but return 0 for 1 */
77static inline int sg_count(struct scatterlist *sg_list, int nbytes,
78			     bool *chained)
79{
80	int sg_nents = __sg_count(sg_list, nbytes, chained);
81
82	if (likely(sg_nents == 1))
83		return 0;
84
85	return sg_nents;
86}
87
88static int dma_map_sg_chained(struct device *dev, struct scatterlist *sg,
89			      unsigned int nents, enum dma_data_direction dir,
90			      bool chained)
91{
92	if (unlikely(chained)) {
93		int i;
94		for (i = 0; i < nents; i++) {
95			dma_map_sg(dev, sg, 1, dir);
96			sg = sg_next(sg);
97		}
98	} else {
99		dma_map_sg(dev, sg, nents, dir);
100	}
101	return nents;
102}
103
104static int dma_unmap_sg_chained(struct device *dev, struct scatterlist *sg,
105				unsigned int nents, enum dma_data_direction dir,
106				bool chained)
107{
108	if (unlikely(chained)) {
109		int i;
110		for (i = 0; i < nents; i++) {
111			dma_unmap_sg(dev, sg, 1, dir);
112			sg = sg_next(sg);
113		}
114	} else {
115		dma_unmap_sg(dev, sg, nents, dir);
116	}
117	return nents;
118}
119