miscemu/emulate.c

   1 #include <stdlib.h>
   2 #include <stdio.h>
   3 #include "miscemu.h"
   4 #include "stddebug.h"
   5 /* #define DEBUG_INT */
   6 #include "debug.h"
   7
   8 struct Win87EmInfoStruct
   9 {
  10     unsigned short Version;
  11     unsigned short SizeSaveArea;
  12     unsigned short WinDataSeg;
  13     unsigned short WinCodeSeg;
  14     unsigned short Have80x87;
  15     unsigned short Unused;
  16 };
  17
  18 /* Implementing this is easy cause Linux and *BSD* ALWAYS have a numerical
  19  * coprocessor. (either real or emulated on kernellevel)
  20  */
  21 /* win87em.dll also sets interrupt vectors: 2 (NMI), 0x34 - 0x3f (emulator
  22  * calls of standard libraries, see Ralph Browns interrupt list), 0x75
  23  * (int13 error reporting of coprocessor)
  24  */
  25
  26 /* have a look at /usr/src/linux/arch/i386/math-emu/ *.[ch] for more info
  27  * especially control_w.h and status_w.h
  28  */
  29 /* FIXME: Only skeletal implementation for now */
  30
  31 void WINAPI WIN87_fpmath( CONTEXT *context )
  32 {
  33     dprintf_int(stddeb, "_fpmath: (cs:eip=%x:%lx es=%x bx=%04x ax=%04x dx==%04x)\n",
  34                  (WORD)CS_reg(context), EIP_reg(context),
  35                  (WORD)ES_reg(context), BX_reg(context),
  36                  AX_reg(context), DX_reg(context) );
  37
  38     switch(BX_reg(context))
  39     {
  40     case 0: /* install (increase instanceref) emulator, install NMI vector */
  41         AX_reg(context) = 0;
  42         break;
  43
  44     case 1: /* Init Emulator */
  45         AX_reg(context) = 0;
  46         break;
  47
  48     case 2: /* deinstall emulator (decrease instanceref), deinstall NMI vector
  49              * if zero. Every '0' call should have a matching '2' call.
  50              */
  51         AX_reg(context) = 0;
  52         break;
  53
  54     case 3:
  55         /*INT_SetHandler(0x3E,MAKELONG(AX,DX));*/
  56         break;
  57
  58     case 4: /* set control word (& ~(CW_Denormal|CW_Invalid)) */
  59         /* OUT: newset control word in AX */
  60         break;
  61
  62     case 5: /* return internal control word in AX */
  63         break;
  64
  65     case 6: /* round top of stack to integer using method AX & 0x0C00 */
  66         /* returns current controlword */
  67         break;
  68
  69     case 7: /* POP top of stack as integer into DX:AX */
  70         /* IN: AX&0x0C00 rounding protocol */
  71         /* OUT: DX:AX variable popped */
  72         {
  73             DWORD dw=0;
  74             /* I don't know much about asm() programming. This could be
  75              * wrong.
  76              */
  77 /* FIXME: could someone who really understands asm() fix this please? --AJ */
  78 /*            __asm__("fistp %0;wait" : "=m" (dw) : : "memory"); */
  79             dprintf_int(stddeb,"emulate.c:On top of stack was %ld\n",dw);
  80             AX_reg(context) = LOWORD(dw);
  81             DX_reg(context) = HIWORD(dw);
  82         }
  83         break;
  84
  85     case 8: /* restore internal control words from emulator control word */
  86         break;
  87
  88     case 9: /* clear emu control word and some other things */
  89         break;
  90
  91     case 10: /* dunno. but looks like returning nr. of things on stack in AX */
  92         AX_reg(context) = 0;
  93         break;
  94
  95     case 11: /* just returns the installed flag in DX:AX */
  96         DX_reg(context) = 0;
  97         AX_reg(context) = 1;
  98         break;
  99
 100     case 12: /* save AX in some internal state var */
 101         break;
 102
 103     default: /* error. Say that loud and clear */
 104         AX_reg(context) = DX_reg(context) = 0xFFFF;
 105         break;
 106     }
 107 }
 108
 109
 110 void WINAPI WIN87_WinEm87Info(struct Win87EmInfoStruct *pWIS,
 111                               int cbWin87EmInfoStruct)
 112 {
 113   dprintf_int(stddeb, "__WinEm87Info(%p,%d)\n",pWIS,cbWin87EmInfoStruct);
 114 }
 115
 116 void WINAPI WIN87_WinEm87Restore(void *pWin87EmSaveArea,
 117                                  int cbWin87EmSaveArea)
 118 {
 119   dprintf_int(stddeb, "__WinEm87Restore(%p,%d)\n",
 120         pWin87EmSaveArea,cbWin87EmSaveArea);
 121 }
 122
 123 void WINAPI WIN87_WinEm87Save(void *pWin87EmSaveArea, int cbWin87EmSaveArea)
 124 {
 125   dprintf_int(stddeb, "__WinEm87Save(%p,%d)\n",
 126         pWin87EmSaveArea,cbWin87EmSaveArea);
 127 }