arch/avr32/lib/io-readsb.S

   1 /*
   2  * Copyright (C) 2004-2006 Atmel Corporation
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9         .text
  10 .Lnot_word_aligned:
  11 1:      ld.ub   r8, r12[0]
  12         sub     r10, 1
  13         st.b    r11++, r8
  14         reteq   r12
  15         tst     r11, r9
  16         brne    1b
  17
  18         /* fall through */
  19
  20         .global __raw_readsb
  21         .type   __raw_readsb,@function
  22 __raw_readsb:
  23         cp.w    r10, 0
  24         mov     r9, 3
  25         reteq   r12
  26
  27         tst     r11, r9
  28         brne    .Lnot_word_aligned
  29
  30         sub     r10, 4
  31         brlt    2f
  32
  33 1:      ldins.b r8:t, r12[0]
  34         ldins.b r8:u, r12[0]
  35         ldins.b r8:l, r12[0]
  36         ldins.b r8:b, r12[0]
  37         st.w    r11++, r8
  38         sub     r10, 4
  39         brge    1b
  40
  41 2:      sub     r10, -4
  42         reteq   r12
  43
  44 3:      ld.ub   r8, r12[0]
  45         sub     r10, 1
  46         st.b    r11++, r8
  47         brne    3b
  48
  49         retal   r12