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 static 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 */ 74 static 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 */ 92 static 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 } 102 103 static int dma_map_sg_chained(struct device *dev, struct scatterlist *sg, 104 unsigned int nents, enum dma_data_direction dir, 105 bool chained) 106 { 107 if (unlikely(chained)) { 108 int i; 109 for (i = 0; i < nents; i++) { 110 dma_map_sg(dev, sg, 1, dir); 111 sg = sg_next(sg); 112 } 113 } else { 114 dma_map_sg(dev, sg, nents, dir); 115 } 116 return nents; 117 } 118 119 static int dma_unmap_sg_chained(struct device *dev, struct scatterlist *sg, 120 unsigned int nents, enum dma_data_direction dir, 121 bool chained) 122 { 123 if (unlikely(chained)) { 124 int i; 125 for (i = 0; i < nents; i++) { 126 dma_unmap_sg(dev, sg, 1, dir); 127 sg = sg_next(sg); 128 } 129 } else { 130 dma_unmap_sg(dev, sg, nents, dir); 131 } 132 return nents; 133 } 134