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 #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 }