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         u64 ptr;
  12         u32 len;
  13         u32 bpid_offset;
  14 };
  15
  16 /*
  17  * convert single dma address to h/w link table format
  18  */
  19 static inline void dma_to_sec4_sg_one(struct sec4_sg_entry *sec4_sg_ptr,
  20                                       dma_addr_t dma, u32 len, u16 offset)
  21 {
  22         sec4_sg_ptr->ptr = cpu_to_caam_dma64(dma);
  23         sec4_sg_ptr->len = cpu_to_caam32(len);
  24         sec4_sg_ptr->bpid_offset = cpu_to_caam32(offset & SEC4_SG_OFFSET_MASK);
  25 #ifdef DEBUG
  26         print_hex_dump(KERN_ERR, "sec4_sg_ptr@: ",
  27                        DUMP_PREFIX_ADDRESS, 16, 4, sec4_sg_ptr,
  28                        sizeof(struct sec4_sg_entry), 1);
  29 #endif
  30 }
  31
  32 /*
  33  * convert scatterlist to h/w link table format
  34  * but does not have final bit; instead, returns last entry
  35  */
  36 static inline struct sec4_sg_entry *
  37 sg_to_sec4_sg(struct scatterlist *sg, int sg_count,
  38               struct sec4_sg_entry *sec4_sg_ptr, u16 offset)
  39 {
  40         while (sg_count) {
  41                 dma_to_sec4_sg_one(sec4_sg_ptr, sg_dma_address(sg),
  42                                    sg_dma_len(sg), offset);
  43                 sec4_sg_ptr++;
  44                 sg = sg_next(sg);
  45                 sg_count--;
  46         }
  47         return sec4_sg_ptr - 1;
  48 }
  49
  50 /*
  51  * convert scatterlist to h/w link table format
  52  * scatterlist must have been previously dma mapped
  53  */
  54 static inline void sg_to_sec4_sg_last(struct scatterlist *sg, int sg_count,
  55                                       struct sec4_sg_entry *sec4_sg_ptr,
  56                                       u16 offset)
  57 {
  58         sec4_sg_ptr = sg_to_sec4_sg(sg, sg_count, sec4_sg_ptr, offset);
  59         sec4_sg_ptr->len |= cpu_to_caam32(SEC4_SG_LEN_FIN);
  60 }
  61
  62 static inline struct sec4_sg_entry *sg_to_sec4_sg_len(
  63         struct scatterlist *sg, unsigned int total,
  64         struct sec4_sg_entry *sec4_sg_ptr)
  65 {
  66         do {
  67                 unsigned int len = min(sg_dma_len(sg), total);
  68
  69                 dma_to_sec4_sg_one(sec4_sg_ptr, sg_dma_address(sg), len, 0);
  70                 sec4_sg_ptr++;
  71                 sg = sg_next(sg);
  72                 total -= len;
  73         } while (total);
  74         return sec4_sg_ptr - 1;
  75 }
  76
  77 /* derive number of elements in scatterlist, but return 0 for 1 */
  78 static inline int sg_count(struct scatterlist *sg_list, int nbytes)
  79 {
  80         int sg_nents = sg_nents_for_len(sg_list, nbytes);
  81
  82         if (likely(sg_nents == 1))
  83                 return 0;
  84
  85         return sg_nents;
  86 }