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 = scatterwalk_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 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 = scatterwalk_sg_next(sg); 71 } 72 73 return sg_nents; 74 } 75 76 /* derive number of elements in scatterlist, but return 0 for 1 */ 77 static 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 88 static 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 = scatterwalk_sg_next(sg); 97 } 98 } else { 99 dma_map_sg(dev, sg, nents, dir); 100 } 101 return nents; 102 } 103 104 static 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 = scatterwalk_sg_next(sg); 113 } 114 } else { 115 dma_unmap_sg(dev, sg, nents, dir); 116 } 117 return nents; 118 } 119