dlls/kernel/win87em.c

   1 #include <stdlib.h>
   2 #include "miscemu.h"
   3 #include "debugtools.h"
   4
   5 DEFAULT_DEBUG_CHANNEL(int);
   6
   7 struct Win87EmInfoStruct
   8 {
   9     unsigned short Version;
  10     unsigned short SizeSaveArea;
  11     unsigned short WinDataSeg;
  12     unsigned short WinCodeSeg;
  13     unsigned short Have80x87;
  14     unsigned short Unused;
  15 };
  16
  17 /* Implementing this is easy cause Linux and *BSD* ALWAYS have a numerical
  18  * coprocessor. (either real or emulated on kernellevel)
  19  */
  20 /* win87em.dll also sets interrupt vectors: 2 (NMI), 0x34 - 0x3f (emulator
  21  * calls of standard libraries, see Ralph Browns interrupt list), 0x75
  22  * (int13 error reporting of coprocessor)
  23  */
  24
  25 /* have a look at /usr/src/linux/arch/i386/math-emu/ *.[ch] for more info
  26  * especially control_w.h and status_w.h
  27  */
  28 /* FIXME: Still rather skeletal implementation only */
  29
  30 static BOOL Installed = 0;
  31 static WORD RefCount = 0;
  32 static WORD CtrlWord_1 = 0;
  33 static WORD CtrlWord_2 = 0;
  34 static WORD CtrlWord_Internal = 0;
  35 static WORD StatusWord_1 = 0x000b;
  36 static WORD StatusWord_2 = 0;
  37 static WORD StatusWord_3 = 0;
  38 static WORD StackTop = 175;
  39 static WORD StackBottom = 0;
  40 static WORD Inthandler02hVar = 1;
  41
  42 static void WIN87_ClearCtrlWord( CONTEXT86 *context )
  43 {
  44     AX_reg(context) = 0;
  45     if (Installed)
  46 #ifdef __i386__
  47         __asm__("fclex");
  48 #else
  49         ;
  50 #endif
  51     StatusWord_3 = StatusWord_2 = 0;
  52 }
  53
  54 static void WIN87_SetCtrlWord( CONTEXT86 *context )
  55 {
  56     CtrlWord_1 = AX_reg(context);
  57     AX_reg(context) &= 0xff3c;
  58     if (Installed) {
  59         CtrlWord_Internal = AX_reg(context);
  60 #ifdef __i386__
  61         __asm__("wait;fldcw %0" : : "m" (CtrlWord_Internal));
  62 #endif
  63     }
  64     CtrlWord_2 = AX_reg(context);
  65 }
  66
  67 void WIN87_Init( CONTEXT86 *context )
  68 {
  69     if (Installed) {
  70 #ifdef __i386__
  71         __asm__("fninit");
  72         __asm__("fninit");
  73 #endif
  74     }
  75     StackBottom = StackTop;
  76     AX_reg(context) = 0x1332;
  77     WIN87_SetCtrlWord(context);
  78     WIN87_ClearCtrlWord(context);
  79 }
  80
  81 /***********************************************************************
  82  *              WIN87_fpmath
  83  */
  84 void WINAPI WIN87_fpmath( CONTEXT86 *context )
  85 {
  86     TRACE("(cs:eip=%x:%lx es=%x bx=%04x ax=%04x dx==%04x)\n",
  87                  (WORD)context->SegCs, context->Eip,
  88                  (WORD)context->SegEs, BX_reg(context),
  89                  AX_reg(context), DX_reg(context) );
  90
  91     switch(BX_reg(context))
  92     {
  93     case 0: /* install (increase instanceref) emulator, install NMI vector */
  94         RefCount++;
  95 #if 0
  96         if (Installed)
  97             InstallIntVecs02hAnd75h();
  98 #endif
  99         WIN87_Init(context);
 100         AX_reg(context) = 0;
 101         break;
 102
 103     case 1: /* Init Emulator */
 104         WIN87_Init(context);
 105         break;
 106
 107     case 2: /* deinstall emulator (decrease instanceref), deinstall NMI vector
 108              * if zero. Every '0' call should have a matching '2' call.
 109              */
 110         WIN87_Init(context);
 111         RefCount--;
 112 #if 0
 113         if (!RefCount && Installed)
 114             RestoreInt02h();
 115 #endif
 116
 117         break;
 118
 119     case 3:
 120         /*INT_SetHandler(0x3E,MAKELONG(AX,DX));*/
 121         break;
 122
 123     case 4: /* set control word (& ~(CW_Denormal|CW_Invalid)) */
 124         /* OUT: newset control word in AX */
 125         WIN87_SetCtrlWord(context);
 126         break;
 127
 128     case 5: /* return internal control word in AX */
 129         AX_reg(context) = CtrlWord_1;
 130         break;
 131
 132     case 6: /* round top of stack to integer using method AX & 0x0C00 */
 133         /* returns current controlword */
 134         {
 135             DWORD dw=0;
 136             WORD save,mask;
 137             /* I don't know much about asm() programming. This could be
 138              * wrong.
 139              */
 140 #ifdef __i386__
 141            __asm__ __volatile__("fstcw %0;wait" : "=m" (save) : : "memory");
 142            __asm__ __volatile__("fstcw %0;wait" : "=m" (mask) : : "memory");
 143            __asm__ __volatile__("orw $0xC00,%0" : "=m" (mask) : : "memory");
 144            __asm__ __volatile__("fldcw %0;wait" : : "m" (mask));
 145            __asm__ __volatile__("frndint");
 146            __asm__ __volatile__("fist %0;wait" : "=m" (dw) : : "memory");
 147            __asm__ __volatile__("fldcw %0" : : "m" (save));
 148 #endif
 149             TRACE("On top of stack is %ld\n",dw);
 150         }
 151         break;
 152
 153     case 7: /* POP top of stack as integer into DX:AX */
 154         /* IN: AX&0x0C00 rounding protocol */
 155         /* OUT: DX:AX variable popped */
 156         {
 157             DWORD dw=0;
 158             /* I don't know much about asm() programming. This could be
 159              * wrong.
 160              */
 161 /* FIXME: could someone who really understands asm() fix this please? --AJ */
 162 /*            __asm__("fistp %0;wait" : "=m" (dw) : : "memory"); */
 163             TRACE("On top of stack was %ld\n",dw);
 164             AX_reg(context) = LOWORD(dw);
 165             DX_reg(context) = HIWORD(dw);
 166         }
 167         break;
 168
 169     case 8: /* restore internal status words from emulator status word */
 170         AX_reg(context) = 0;
 171         if (Installed) {
 172 #ifdef __i386__
 173             __asm__("fstsw %0;wait" : "=m" (StatusWord_1));
 174 #endif
 175             AL_reg(context) = (BYTE)StatusWord_1 & 0x3f;
 176         }
 177         AX_reg(context) |= StatusWord_2;
 178         AX_reg(context) &= 0x1fff;
 179         StatusWord_2 = AX_reg(context);
 180         break;
 181
 182     case 9: /* clear emu control word and some other things */
 183         WIN87_ClearCtrlWord(context);
 184         break;
 185
 186     case 10: /* dunno. but looks like returning nr. of things on stack in AX */
 187         AX_reg(context) = 0;
 188         break;
 189
 190     case 11: /* just returns the installed flag in DX:AX */
 191         DX_reg(context) = 0;
 192         AX_reg(context) = Installed;
 193         break;
 194
 195     case 12: /* save AX in some internal state var */
 196         Inthandler02hVar = AX_reg(context);
 197         break;
 198
 199     default: /* error. Say that loud and clear */
 200         FIXME("unhandled switch %d\n",BX_reg(context));
 201         AX_reg(context) = DX_reg(context) = 0xFFFF;
 202         break;
 203     }
 204 }
 205
 206 /***********************************************************************
 207  *              WIN87_WinEm87Info
 208  */
 209 void WINAPI WIN87_WinEm87Info(struct Win87EmInfoStruct *pWIS,
 210                               int cbWin87EmInfoStruct)
 211 {
 212   FIXME("(%p,%d), stub !\n",pWIS,cbWin87EmInfoStruct);
 213 }
 214
 215 /***********************************************************************
 216  *              WIN87_WinEm87Restore
 217  */
 218 void WINAPI WIN87_WinEm87Restore(void *pWin87EmSaveArea,
 219                                  int cbWin87EmSaveArea)
 220 {
 221   FIXME("(%p,%d), stub !\n",
 222         pWin87EmSaveArea,cbWin87EmSaveArea);
 223 }
 224
 225 /***********************************************************************
 226  *              WIN87_WinEm87Save
 227  */
 228 void WINAPI WIN87_WinEm87Save(void *pWin87EmSaveArea, int cbWin87EmSaveArea)
 229 {
 230   FIXME("(%p,%d), stub !\n",
 231         pWin87EmSaveArea,cbWin87EmSaveArea);
 232 }