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, u16 offset)
  15 {
  16         sec4_sg_ptr->ptr = dma;
  17         sec4_sg_ptr->len = len;
  18         sec4_sg_ptr->buf_pool_id = 0;
  19         sec4_sg_ptr->offset = offset & SEC4_SG_OFFSET_MASK;
  20 #ifdef DEBUG
  21         print_hex_dump(KERN_ERR, "sec4_sg_ptr@: ",
  22                        DUMP_PREFIX_ADDRESS, 16, 4, sec4_sg_ptr,
  23                        sizeof(struct sec4_sg_entry), 1);
  24 #endif
  25 }
  26
  27 /*
  28  * convert scatterlist to h/w link table format
  29  * but does not have final bit; instead, returns last entry
  30  */
  31 static inline struct sec4_sg_entry *
  32 sg_to_sec4_sg(struct scatterlist *sg, int sg_count,
  33               struct sec4_sg_entry *sec4_sg_ptr, u16 offset)
  34 {
  35         while (sg_count) {
  36                 dma_to_sec4_sg_one(sec4_sg_ptr, sg_dma_address(sg),
  37                                    sg_dma_len(sg), offset);
  38                 sec4_sg_ptr++;
  39                 sg = sg_next(sg);
  40                 sg_count--;
  41         }
  42         return sec4_sg_ptr - 1;
  43 }
  44
  45 /*
  46  * convert scatterlist to h/w link table format
  47  * scatterlist must have been previously dma mapped
  48  */
  49 static inline void sg_to_sec4_sg_last(struct scatterlist *sg, int sg_count,
  50                                       struct sec4_sg_entry *sec4_sg_ptr,
  51                                       u16 offset)
  52 {
  53         sec4_sg_ptr = sg_to_sec4_sg(sg, sg_count, sec4_sg_ptr, offset);
  54         sec4_sg_ptr->len |= SEC4_SG_LEN_FIN;
  55 }
  56
  57 static inline struct sec4_sg_entry *sg_to_sec4_sg_len(
  58         struct scatterlist *sg, unsigned int total,
  59         struct sec4_sg_entry *sec4_sg_ptr)
  60 {
  61         do {
  62                 unsigned int len = min(sg_dma_len(sg), total);
  63
  64                 dma_to_sec4_sg_one(sec4_sg_ptr, sg_dma_address(sg), len, 0);
  65                 sec4_sg_ptr++;
  66                 sg = sg_next(sg);
  67                 total -= len;
  68         } while (total);
  69         return sec4_sg_ptr - 1;
  70 }
  71
  72 /* derive number of elements in scatterlist, but return 0 for 1 */
  73 static inline int sg_count(struct scatterlist *sg_list, int nbytes)
  74 {
  75         int sg_nents = sg_nents_for_len(sg_list, nbytes);
  76
  77         if (likely(sg_nents == 1))
  78                 return 0;
  79
  80         return sg_nents;
  81 }