Pileus Git - ~andy/linux/blob - drivers/crypto/caam/sg_sw_sec4.h

   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 }
  85
  86 /* Copy from len bytes of sg to dest, starting from beginning */
  87 static inline void sg_copy(u8 *dest, struct scatterlist *sg, unsigned int len)
  88 {
  89         struct scatterlist *current_sg = sg;
  90         int cpy_index = 0, next_cpy_index = current_sg->length;
  91
  92         while (next_cpy_index < len) {
  93                 memcpy(dest + cpy_index, (u8 *) sg_virt(current_sg),
  94                        current_sg->length);
  95                 current_sg = scatterwalk_sg_next(current_sg);
  96                 cpy_index = next_cpy_index;
  97                 next_cpy_index += current_sg->length;
  98         }
  99         if (cpy_index < len)
 100                 memcpy(dest + cpy_index, (u8 *) sg_virt(current_sg),
 101                        len - cpy_index);
 102 }
 103
 104 /* Copy sg data, from to_skip to end, to dest */
 105 static inline void sg_copy_part(u8 *dest, struct scatterlist *sg,
 106                                       int to_skip, unsigned int end)
 107 {
 108         struct scatterlist *current_sg = sg;
 109         int sg_index, cpy_index;
 110
 111         sg_index = current_sg->length;
 112         while (sg_index <= to_skip) {
 113                 current_sg = scatterwalk_sg_next(current_sg);
 114                 sg_index += current_sg->length;
 115         }
 116         cpy_index = sg_index - to_skip;
 117         memcpy(dest, (u8 *) sg_virt(current_sg) +
 118                current_sg->length - cpy_index, cpy_index);
 119         current_sg = scatterwalk_sg_next(current_sg);
 120         if (end - sg_index)
 121                 sg_copy(dest + cpy_index, current_sg, end - sg_index);
 122 }