| Yuan Kang | a299c83 | 2012-06-22 19:48:46 -0500 | [diff] [blame^] | 1 | /* |
| 2 | * CAAM/SEC 4.x functions for using scatterlists in caam driver |
| 3 | * |
| 4 | * Copyright 2008-2011 Freescale Semiconductor, Inc. |
| 5 | * |
| 6 | */ |
| 7 | |
| 8 | struct sec4_sg_entry; |
| 9 | |
| 10 | /* |
| 11 | * convert single dma address to h/w link table format |
| 12 | */ |
| 13 | static 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 | */ |
| 32 | static inline struct sec4_sg_entry * |
| 33 | sg_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 | */ |
| 50 | static 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 */ |
| 59 | static inline int __sg_count(struct scatterlist *sg_list, int nbytes) |
| 60 | { |
| 61 | struct scatterlist *sg = sg_list; |
| 62 | int sg_nents = 0; |
| 63 | |
| 64 | while (nbytes > 0) { |
| 65 | sg_nents++; |
| 66 | nbytes -= sg->length; |
| 67 | if (!sg_is_last(sg) && (sg + 1)->length == 0) |
| 68 | BUG(); /* Not support chaining */ |
| 69 | sg = scatterwalk_sg_next(sg); |
| 70 | } |
| 71 | |
| 72 | return sg_nents; |
| 73 | } |
| 74 | |
| 75 | /* derive number of elements in scatterlist, but return 0 for 1 */ |
| 76 | static inline int sg_count(struct scatterlist *sg_list, int nbytes) |
| 77 | { |
| 78 | int sg_nents = __sg_count(sg_list, nbytes); |
| 79 | |
| 80 | if (likely(sg_nents == 1)) |
| 81 | return 0; |
| 82 | |
| 83 | return sg_nents; |
| 84 | } |