arch/m68k-amiga/graphics/setchiprev.c

   1 /*
   2     Copyright © 1995-2013, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Graphics function SetChipRev()
   6     Lang: english
   7 */
   8 #include <aros/debug.h>
   9 #include <graphics/gfxbase.h>
  10 #include <hardware/custom.h>
  11
  12 #include <proto/graphics.h>
  13
  14 /* See rom/graphics/setchiprev.c for documentation */
  15
  16 AROS_LH1(ULONG, SetChipRev,
  17     AROS_LHA(ULONG, ChipRev, D0),
  18     struct GfxBase *, GfxBase, 148, Graphics)
  19 {
  20     AROS_LIBFUNC_INIT
  21
  22     volatile struct Custom *custom = (struct Custom*)0xdff000;
  23     UWORD vposr, deniseid1, deniseid2, deniseid3;
  24     UBYTE chipflags = 0;
  25
  26     vposr = custom->vposr & 0x7f00;
  27     if (vposr >= 0x2000)
  28         chipflags |= GFXF_HR_AGNUS;
  29     if (vposr >= 0x2200) {
  30         chipflags |= GFXF_AA_ALICE | GFXF_AA_LISA | GFXF_HR_DENISE;
  31     } else {
  32         Disable();
  33         deniseid1 = custom->deniseid & 0x00ff;
  34         custom->deniseid = custom->dmaconr;
  35         deniseid2 = custom->deniseid & 0x00ff;
  36         custom->deniseid = custom->dmaconr ^ 0x8000;
  37         deniseid3 = custom->deniseid & 0x00ff;
  38         Enable();
  39         if (deniseid1 == deniseid2 && deniseid2 == deniseid3 && deniseid1 == 0xfc)
  40             chipflags |= GFXF_HR_DENISE;
  41         }
  42
  43     if (ChipRev != SETCHIPREV_BEST) {
  44         if (ChipRev == SETCHIPREV_A && chipflags >= SETCHIPREV_A)
  45             chipflags = SETCHIPREV_A;
  46         else if (ChipRev == SETCHIPREV_ECS && chipflags >= SETCHIPREV_ECS)
  47             chipflags = SETCHIPREV_ECS;
  48         else if (ChipRev == SETCHIPREV_AA && chipflags >= SETCHIPREV_AA)
  49             chipflags = SETCHIPREV_AA;
  50     }
  51     GfxBase->ChipRevBits0 = chipflags;
  52
  53     return GfxBase->ChipRevBits0;
  54
  55     AROS_LIBFUNC_EXIT
  56 } /* SetChipRev */