contrib/loaders/flash/fm4/write.S

   1 /*
   2  * Spansion FM4 flash write algorithm
   3  *
   4  * Copyright (c) 2015 Andreas Färber
   5  *
   6  * Based on S6E2CC_MN709-00007 for S6E2CC/C5/C4/C3/C2/C1 series
   7  */
   8
   9 #include "fm4.h"
  10
  11 #define RESULT_OKAY     0
  12 #define RESULT_NONE     1
  13 #define RESULT_TIMEOUT  2
  14
  15         .macro busy_wait, res, addr, data, tmp1, tmp2, tmp3
  16
  17         ldrb    \tmp1, [\addr] /* ignore */
  18         and     \tmp2, \data, #FLASH_DPOL
  19 1001:
  20         ldrb    \tmp1, [\addr]
  21         and     \tmp3, \tmp1, #FLASH_DPOL
  22         cmp     \tmp3, \tmp2
  23         beq     1010f
  24
  25         and     \tmp3, \tmp1, #FLASH_TLOV
  26         cmp     \tmp3, #0
  27         beq     1001b
  28
  29         ldrb    \tmp1, [\addr]
  30         and     \tmp3, \tmp1, #FLASH_DPOL
  31         cmp     \tmp3, \tmp2
  32         beq     1010f
  33
  34         mov     \res, #RESULT_TIMEOUT
  35         bkpt    #0
  36 1010:
  37         .endm
  38
  39
  40         .macro write_one, res, cmdseqaddr1, cmdseqaddr2, pa, pd, tmp1, tmp2, tmp3
  41
  42         mov     \tmp1, #0xAA
  43         strh    \tmp1, [\cmdseqaddr1]
  44         mov     \tmp1, #0x55
  45         strh    \tmp1, [\cmdseqaddr2]
  46         mov     \tmp1, #0xA0
  47         strh    \tmp1, [\cmdseqaddr1]
  48         strh    \pd, [\pa]
  49
  50         busy_wait \res, \pa, \pd, \tmp1, \tmp2, \tmp3
  51
  52         .endm
  53
  54
  55         .macro write, cmdseqaddr1, cmdseqaddr2, dest, src, cnt, res, tmp1, tmp2, tmp3, tmp4
  56
  57         mov     \res, #RESULT_NONE
  58 2001:
  59         cbz     \cnt, 2010f
  60
  61         ldrh    \tmp1, [\src]
  62         write_one \res, \cmdseqaddr1, \cmdseqaddr2, \dest, \tmp1, \tmp2, \tmp3, \tmp4
  63
  64         sub     \cnt, \cnt, #1
  65         add     \dest, \dest, #2
  66         add     \src, \src, #2
  67         b       2001b
  68 2010:
  69         mov     \res, #RESULT_OKAY
  70         .endm
  71
  72
  73         /* r0 = 0xAA8
  74          * r1 = 0x554
  75          * r2 = dest
  76          * r3 = src
  77          * r4 = cnt
  78          * r5 = result
  79          */
  80 write:
  81         write r0, r1, r2, r3, r4, r5, r6, r7, r8, r9
  82
  83         bkpt    #0
  84
  85 data: