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 #include "regs.h" 9 10 struct sec4_sg_entry; 11 12 /* 13 * convert single dma address to h/w link table format 14 */ 15 static inline void dma_to_sec4_sg_one(struct sec4_sg_entry *sec4_sg_ptr, 16 dma_addr_t dma, u32 len, u16 offset) 17 { 18 sec4_sg_ptr->ptr = cpu_to_caam_dma(dma); 19 sec4_sg_ptr->len = cpu_to_caam32(len); 20 sec4_sg_ptr->bpid_offset = cpu_to_caam32(offset & SEC4_SG_OFFSET_MASK); 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, u16 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 u16 offset) 53 { 54 sec4_sg_ptr = sg_to_sec4_sg(sg, sg_count, sec4_sg_ptr, offset); 55 sec4_sg_ptr->len |= cpu_to_caam32(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 /* derive number of elements in scatterlist, but return 0 for 1 */ 74 static inline int sg_count(struct scatterlist *sg_list, int nbytes) 75 { 76 int sg_nents = sg_nents_for_len(sg_list, nbytes); 77 78 if (likely(sg_nents == 1)) 79 return 0; 80 81 return sg_nents; 82 } 83