arch/m68k-amiga/card/cardaccessspeed.c

   1 /*
   2     Copyright © 1995-2014, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: CardAccessSpeed() function.
   6     Lang: english
   7 */
   8
   9 #include "card_intern.h"
  10
  11 AROS_LH2(ULONG, CardAccessSpeed,
  12         AROS_LHA(struct CardHandle*, handle, A1),
  13         AROS_LHA(ULONG, nanoseconds, D0),
  14         struct CardResource*, CardResource, 9, Card)
  15 {
  16     AROS_LIBFUNC_INIT
  17
  18     volatile struct GayleIO *gio = (struct GayleIO*)GAYLE_BASE;
  19     UBYTE v, speed;
  20
  21     CARDDEBUG(bug("CardAccessSpeed(%p,%d)\n", handle, nanoseconds));
  22
  23     if (!ISMINE)
  24         return 0;
  25
  26     speed = 0;
  27
  28     if (nanoseconds > 720)
  29         return 0;
  30
  31     if (nanoseconds > 250) {
  32         speed = GAYLE_CFG_720NS;
  33         nanoseconds = 720;
  34     } else if (nanoseconds > 150) {
  35         speed = GAYLE_CFG_250NS;
  36         nanoseconds = 250;
  37     } else if (nanoseconds > 100) {
  38         speed = GAYLE_CFG_150NS;
  39         nanoseconds = 150;
  40     } else {
  41         speed = GAYLE_CFG_100NS;
  42         nanoseconds = 100;
  43     }
  44
  45     Disable();
  46     v = gio->config & ~GAYLE_CFG_SPEED;
  47     v |= speed;
  48     gio->config = v;
  49     Enable();
  50
  51     return nanoseconds;
  52
  53     AROS_LIBFUNC_EXIT
  54 }