--- /dev/null
+/*
+ * Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
+ *
+ * (c) Copyright 1996 - 2001 Gary Henderson (gary.henderson@ntlworld.com) and
+ * Jerremy Koot (jkoot@snes9x.com)
+ *
+ * Super FX C emulator code
+ * (c) Copyright 1997 - 1999 Ivar (ivar@snes9x.com) and
+ * Gary Henderson.
+ * Super FX assembler emulator code (c) Copyright 1998 zsKnight and _Demo_.
+ *
+ * DSP1 emulator code (c) Copyright 1998 Ivar, _Demo_ and Gary Henderson.
+ * C4 asm and some C emulation code (c) Copyright 2000 zsKnight and _Demo_.
+ * C4 C code (c) Copyright 2001 Gary Henderson (gary.henderson@ntlworld.com).
+ *
+ * DOS port code contains the works of other authors. See headers in
+ * individual files.
+ *
+ * Snes9x homepage: http://www.snes9x.com
+ *
+ * Permission to use, copy, modify and distribute Snes9x in both binary and
+ * source form, for non-commercial purposes, is hereby granted without fee,
+ * providing that this license information and copyright notice appear with
+ * all copies and any derived work.
+ *
+ * This software is provided 'as-is', without any express or implied
+ * warranty. In no event shall the authors be held liable for any damages
+ * arising from the use of this software.
+ *
+ * Snes9x is freeware for PERSONAL USE only. Commercial users should
+ * seek permission of the copyright holders first. Commercial use includes
+ * charging money for Snes9x or software derived from Snes9x.
+ *
+ * The copyright holders request that bug fixes and improvements to the code
+ * should be forwarded to them so everyone can benefit from the modifications
+ * in future versions.
+ *
+ * Super NES and Super Nintendo Entertainment System are trademarks of
+ * Nintendo Co., Limited and its subsidiary companies.
+ */
+#include "fxemu.h"
+#include "fxinst.h"
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+/* The FxChip Emulator's internal variables */
+struct FxRegs_s GSU = {0};
+
+uint32 (**fx_ppfFunctionTable)(uint32) = 0;
+void (**fx_ppfPlotTable)() = 0;
+void (**fx_ppfOpcodeTable)() = 0;
+
+#if 0
+void fx_setCache()
+{
+ uint32 c;
+ GSU.bCacheActive = TRUE;
+ GSU.pvRegisters[0x3e] &= 0xf0;
+ c = (uint32)GSU.pvRegisters[0x3e];
+ c |= ((uint32)GSU.pvRegisters[0x3f])<<8;
+ if(c == GSU.vCacheBaseReg)
+ return;
+ GSU.vCacheBaseReg = c;
+ GSU.vCacheFlags = 0;
+ if(c < (0x10000-512))
+ {
+ uint8 const* t = &ROM(c);
+ memcpy(GSU.pvCache,t,512);
+ }
+ else
+ {
+ uint8 const* t1;
+ uint8 const* t2;
+ uint32 i = 0x10000 - c;
+ t1 = &ROM(c);
+ t2 = &ROM(0);
+ memcpy(GSU.pvCache,t1,i);
+ memcpy(&GSU.pvCache[i],t2,512-i);
+ }
+}
+#endif
+
+void FxCacheWriteAccess(uint16 vAddress)
+{
+#if 0
+ if(!GSU.bCacheActive)
+ {
+ uint8 v = GSU.pvCache[GSU.pvCache[vAddress&0x1ff];
+ fx_setCache();
+ GSU.pvCache[GSU.pvCache[vAddress&0x1ff] = v;
+ }
+#endif
+ if((vAddress & 0x00f) == 0x00f)
+ GSU.vCacheFlags |= 1 << ((vAddress&0x1f0) >> 4);
+}
+
+void FxFlushCache()
+{
+ GSU.vCacheFlags = 0;
+ GSU.vCacheBaseReg = 0;
+ GSU.bCacheActive = FALSE;
+// GSU.vPipe = 0x1;
+}
+
+static void fx_backupCache()
+{
+#if 0
+ uint32 i;
+ uint32 v = GSU.vCacheFlags;
+ uint32 c = USEX16(GSU.vCacheBaseReg);
+ if(v)
+ for(i=0; i<32; i++)
+ {
+ if(v&1)
+ {
+ if(c < (0x10000-16))
+ {
+ uint8 * t = &GSU.pvPrgBank[c];
+ memcpy(&GSU.avCacheBackup[i<<4],t,16);
+ memcpy(t,&GSU.pvCache[i<<4],16);
+ }
+ else
+ {
+ uint8 * t1;
+ uint8 * t2;
+ uint32 a = 0x10000 - c;
+ t1 = &GSU.pvPrgBank[c];
+ t2 = &GSU.pvPrgBank[0];
+ memcpy(&GSU.avCacheBackup[i<<4],t1,a);
+ memcpy(t1,&GSU.pvCache[i<<4],a);
+ memcpy(&GSU.avCacheBackup[(i<<4)+a],t2,16-a);
+ memcpy(t2,&GSU.pvCache[(i<<4)+a],16-a);
+ }
+ }
+ c = USEX16(c+16);
+ v >>= 1;
+ }
+#endif
+}
+
+static void fx_restoreCache()
+{
+#if 0
+ uint32 i;
+ uint32 v = GSU.vCacheFlags;
+ uint32 c = USEX16(GSU.vCacheBaseReg);
+ if(v)
+ for(i=0; i<32; i++)
+ {
+ if(v&1)
+ {
+ if(c < (0x10000-16))
+ {
+ uint8 * t = &GSU.pvPrgBank[c];
+ memcpy(t,&GSU.avCacheBackup[i<<4],16);
+ memcpy(&GSU.pvCache[i<<4],t,16);
+ }
+ else
+ {
+ uint8 * t1;
+ uint8 * t2;
+ uint32 a = 0x10000 - c;
+ t1 = &GSU.pvPrgBank[c];
+ t2 = &GSU.pvPrgBank[0];
+ memcpy(t1,&GSU.avCacheBackup[i<<4],a);
+ memcpy(&GSU.pvCache[i<<4],t1,a);
+ memcpy(t2,&GSU.avCacheBackup[(i<<4)+a],16-a);
+ memcpy(&GSU.pvCache[(i<<4)+a],t2,16-a);
+ }
+ }
+ c = USEX16(c+16);
+ v >>= 1;
+ }
+#endif
+}
+
+void fx_flushCache()
+{
+ fx_restoreCache();
+ GSU.vCacheFlags = 0;
+ GSU.bCacheActive = FALSE;
+}
+
+static void fx_readRegisterSpace()
+{
+ int i;
+ uint8 *p;
+ static uint32 avHeight[] = { 128, 160, 192, 256 };
+ static uint32 avMult[] = { 16, 32, 32, 64 };
+
+ GSU.vErrorCode = 0;
+
+ /* Update R0-R15 */
+ p = GSU.pvRegisters;
+ for(i=0; i<16; i++)
+ {
+ GSU.avReg[i] = *p++;
+ GSU.avReg[i] += ((uint32)(*p++)) << 8;
+ }
+
+ /* Update other registers */
+ p = GSU.pvRegisters;
+ GSU.vStatusReg = (uint32)p[GSU_SFR];
+ GSU.vStatusReg |= ((uint32)p[GSU_SFR+1]) << 8;
+ GSU.vPrgBankReg = (uint32)p[GSU_PBR];
+ GSU.vRomBankReg = (uint32)p[GSU_ROMBR];
+ GSU.vRamBankReg = ((uint32)p[GSU_RAMBR]) & (FX_RAM_BANKS-1);
+ GSU.vCacheBaseReg = (uint32)p[GSU_CBR];
+ GSU.vCacheBaseReg |= ((uint32)p[GSU_CBR+1]) << 8;
+
+ /* Update status register variables */
+ GSU.vZero = !(GSU.vStatusReg & FLG_Z);
+ GSU.vSign = (GSU.vStatusReg & FLG_S) << 12;
+ GSU.vOverflow = (GSU.vStatusReg & FLG_OV) << 16;
+ GSU.vCarry = (GSU.vStatusReg & FLG_CY) >> 2;
+
+ /* Set bank pointers */
+ GSU.pvRamBank = GSU.apvRamBank[GSU.vRamBankReg & 0x3];
+ GSU.pvRomBank = GSU.apvRomBank[GSU.vRomBankReg];
+ GSU.pvPrgBank = GSU.apvRomBank[GSU.vPrgBankReg];
+
+ /* Set screen pointers */
+ GSU.pvScreenBase = &GSU.pvRam[ USEX8(p[GSU_SCBR]) << 10 ];
+ i = (int)(!!(p[GSU_SCMR] & 0x04));
+ i |= ((int)(!!(p[GSU_SCMR] & 0x20))) << 1;
+ GSU.vScreenHeight = GSU.vScreenRealHeight = avHeight[i];
+ GSU.vMode = p[GSU_SCMR] & 0x03;
+#if 0
+ if(GSU.vMode == 2)
+ error illegal color depth GSU.vMode;
+#endif
+ if(i == 3)
+ GSU.vScreenSize = (256/8) * (256/8) * 32;
+ else
+ GSU.vScreenSize = (GSU.vScreenHeight/8) * (256/8) * avMult[GSU.vMode];
+ if (GSU.vPlotOptionReg & 0x10)
+ {
+ /* OBJ Mode (for drawing into sprites) */
+ GSU.vScreenHeight = 256;
+ }
+#if 0
+ if(GSU.pvScreenBase + GSU.vScreenSize > GSU.pvRam + (GSU.nRamBanks * 65536))
+ error illegal address for screen base register
+#else
+ if(GSU.pvScreenBase + GSU.vScreenSize > GSU.pvRam + (GSU.nRamBanks * 65536))
+ GSU.pvScreenBase = GSU.pvRam + (GSU.nRamBanks * 65536) - GSU.vScreenSize;
+#endif
+ GSU.pfPlot = fx_apfPlotTable[GSU.vMode];
+ GSU.pfRpix = fx_apfPlotTable[GSU.vMode + 5];
+
+ fx_ppfOpcodeTable[0x04c] = GSU.pfPlot;
+ fx_ppfOpcodeTable[0x14c] = GSU.pfRpix;
+ fx_ppfOpcodeTable[0x24c] = GSU.pfPlot;
+ fx_ppfOpcodeTable[0x34c] = GSU.pfRpix;
+
+ fx_computeScreenPointers ();
+
+ fx_backupCache();
+}
+
+void fx_computeScreenPointers ()
+{
+ if (GSU.vMode != GSU.vPrevMode ||
+ GSU.vPrevScreenHeight != GSU.vScreenHeight)
+ {
+ int i;
+
+ /* Make a list of pointers to the start of each screen column */
+ switch (GSU.vScreenHeight)
+ {
+ case 128:
+ switch (GSU.vMode)
+ {
+ case 0:
+ for (i = 0; i < 32; i++)
+ {
+ GSU.apvScreen[i] = GSU.pvScreenBase + (i << 4);
+ GSU.x[i] = i << 8;
+ }
+ break;
+ case 1:
+ for (i = 0; i < 32; i++)
+ {
+ GSU.apvScreen[i] = GSU.pvScreenBase + (i << 5);
+ GSU.x[i] = i << 9;
+ }
+ break;
+ case 2:
+ case 3:
+ for (i = 0; i < 32; i++)
+ {
+ GSU.apvScreen[i] = GSU.pvScreenBase + (i << 6);
+ GSU.x[i] = i << 10;
+ }
+ break;
+ }
+ break;
+ case 160:
+ switch (GSU.vMode)
+ {
+ case 0:
+ for (i = 0; i < 32; i++)
+ {
+ GSU.apvScreen[i] = GSU.pvScreenBase + (i << 4);
+ GSU.x[i] = (i << 8) + (i << 6);
+ }
+ break;
+ case 1:
+ for (i = 0; i < 32; i++)
+ {
+ GSU.apvScreen[i] = GSU.pvScreenBase + (i << 5);
+ GSU.x[i] = (i << 9) + (i << 7);
+ }
+ break;
+ case 2:
+ case 3:
+ for (i = 0; i < 32; i++)
+ {
+ GSU.apvScreen[i] = GSU.pvScreenBase + (i << 6);
+ GSU.x[i] = (i << 10) + (i << 8);
+ }
+ break;
+ }
+ break;
+ case 192:
+ switch (GSU.vMode)
+ {
+ case 0:
+ for (i = 0; i < 32; i++)
+ {
+ GSU.apvScreen[i] = GSU.pvScreenBase + (i << 4);
+ GSU.x[i] = (i << 8) + (i << 7);
+ }
+ break;
+ case 1:
+ for (i = 0; i < 32; i++)
+ {
+ GSU.apvScreen[i] = GSU.pvScreenBase + (i << 5);
+ GSU.x[i] = (i << 9) + (i << 8);
+ }
+ break;
+ case 2:
+ case 3:
+ for (i = 0; i < 32; i++)
+ {
+ GSU.apvScreen[i] = GSU.pvScreenBase + (i << 6);
+ GSU.x[i] = (i << 10) + (i << 9);
+ }
+ break;
+ }
+ break;
+ case 256:
+ switch (GSU.vMode)
+ {
+ case 0:
+ for (i = 0; i < 32; i++)
+ {
+ GSU.apvScreen[i] = GSU.pvScreenBase +
+ ((i & 0x10) << 9) + ((i & 0xf) << 8);
+ GSU.x[i] = ((i & 0x10) << 8) + ((i & 0xf) << 4);
+ }
+ break;
+ case 1:
+ for (i = 0; i < 32; i++)
+ {
+ GSU.apvScreen[i] = GSU.pvScreenBase +
+ ((i & 0x10) << 10) + ((i & 0xf) << 9);
+ GSU.x[i] = ((i & 0x10) << 9) + ((i & 0xf) << 5);
+ }
+ break;
+ case 2:
+ case 3:
+ for (i = 0; i < 32; i++)
+ {
+ GSU.apvScreen[i] = GSU.pvScreenBase +
+ ((i & 0x10) << 11) + ((i & 0xf) << 10);
+ GSU.x[i] = ((i & 0x10) << 10) + ((i & 0xf) << 6);
+ }
+ break;
+ }
+ break;
+ }
+ GSU.vPrevMode = GSU.vMode;
+ GSU.vPrevScreenHeight = GSU.vScreenHeight;
+ }
+}
+
+static void fx_writeRegisterSpace()
+{
+ int i;
+ uint8 *p;
+
+ p = GSU.pvRegisters;
+ for(i=0; i<16; i++)
+ {
+ *p++ = (uint8)GSU.avReg[i];
+ *p++ = (uint8)(GSU.avReg[i] >> 8);
+ }
+
+ /* Update status register */
+ if( USEX16(GSU.vZero) == 0 ) SF(Z);
+ else CF(Z);
+ if( GSU.vSign & 0x8000 ) SF(S);
+ else CF(S);
+ if(GSU.vOverflow >= 0x8000 || GSU.vOverflow < -0x8000) SF(OV);
+ else CF(OV);
+ if(GSU.vCarry) SF(CY);
+ else CF(CY);
+
+ p = GSU.pvRegisters;
+ p[GSU_SFR] = (uint8)GSU.vStatusReg;
+ p[GSU_SFR+1] = (uint8)(GSU.vStatusReg>>8);
+ p[GSU_PBR] = (uint8)GSU.vPrgBankReg;
+ p[GSU_ROMBR] = (uint8)GSU.vRomBankReg;
+ p[GSU_RAMBR] = (uint8)GSU.vRamBankReg;
+ p[GSU_CBR] = (uint8)GSU.vCacheBaseReg;
+ p[GSU_CBR+1] = (uint8)(GSU.vCacheBaseReg>>8);
+
+ fx_restoreCache();
+}
+
+/* Reset the FxChip */
+void FxReset(struct FxInit_s *psFxInfo)
+{
+ int i;
+ static uint32 (**appfFunction[])(uint32) = {
+ &fx_apfFunctionTable[0],
+#if 0
+ &fx_a_apfFunctionTable[0],
+ &fx_r_apfFunctionTable[0],
+ &fx_ar_apfFunctionTable[0],
+#endif
+ };
+ static void (**appfPlot[])() = {
+ &fx_apfPlotTable[0],
+#if 0
+ &fx_a_apfPlotTable[0],
+ &fx_r_apfPlotTable[0],
+ &fx_ar_apfPlotTable[0],
+#endif
+ };
+ static void (**appfOpcode[])() = {
+ &fx_apfOpcodeTable[0],
+#if 0
+ &fx_a_apfOpcodeTable[0],
+ &fx_r_apfOpcodeTable[0],
+ &fx_ar_apfOpcodeTable[0],
+#endif
+ };
+
+ /* Get function pointers for the current emulation mode */
+ fx_ppfFunctionTable = appfFunction[psFxInfo->vFlags & 0x3];
+ fx_ppfPlotTable = appfPlot[psFxInfo->vFlags & 0x3];
+ fx_ppfOpcodeTable = appfOpcode[psFxInfo->vFlags & 0x3];
+
+ /* Clear all internal variables */
+ memset((uint8*)&GSU,0,sizeof(struct FxRegs_s));
+
+ /* Set default registers */
+ GSU.pvSreg = GSU.pvDreg = &R0;
+
+ /* Set RAM and ROM pointers */
+ GSU.pvRegisters = psFxInfo->pvRegisters;
+ GSU.nRamBanks = psFxInfo->nRamBanks;
+ GSU.pvRam = psFxInfo->pvRam;
+ GSU.nRomBanks = psFxInfo->nRomBanks;
+ GSU.pvRom = psFxInfo->pvRom;
+ GSU.vPrevScreenHeight = ~0;
+ GSU.vPrevMode = ~0;
+
+ /* The GSU can't access more than 2mb (16mbits) */
+ if(GSU.nRomBanks > 0x20)
+ GSU.nRomBanks = 0x20;
+
+ /* Clear FxChip register space */
+ memset(GSU.pvRegisters,0,0x300);
+
+ /* Set FxChip version Number */
+ GSU.pvRegisters[0x3b] = 0;
+
+ /* Make ROM bank table */
+ for(i=0; i<256; i++)
+ {
+ uint32 b = i & 0x7f;
+ if (b >= 0x40)
+ {
+ if (GSU.nRomBanks > 1)
+ b %= GSU.nRomBanks;
+ else
+ b &= 1;
+
+ GSU.apvRomBank[i] = &GSU.pvRom[ b << 16 ];
+ }
+ else
+ {
+ b %= GSU.nRomBanks * 2;
+ GSU.apvRomBank[i] = &GSU.pvRom[ (b << 16) + 0x200000];
+ }
+ }
+
+ /* Make RAM bank table */
+ for(i=0; i<4; i++)
+ {
+ GSU.apvRamBank[i] = &GSU.pvRam[(i % GSU.nRamBanks) << 16];
+ GSU.apvRomBank[0x70 + i] = GSU.apvRamBank[i];
+ }
+
+ /* Start with a nop in the pipe */
+ GSU.vPipe = 0x01;
+
+ /* Set pointer to GSU cache */
+ GSU.pvCache = &GSU.pvRegisters[0x100];
+
+ fx_readRegisterSpace();
+}
+
+static uint8 fx_checkStartAddress()
+{
+ /* Check if we start inside the cache */
+ if(GSU.bCacheActive && R15 >= GSU.vCacheBaseReg && R15 < (GSU.vCacheBaseReg+512))
+ return TRUE;
+
+ /* Check if we're in an unused area */
+ if(GSU.vPrgBankReg < 0x40 && R15 < 0x8000)
+ return FALSE;
+ if(GSU.vPrgBankReg >= 0x60 && GSU.vPrgBankReg <= 0x6f)
+ return FALSE;
+ if(GSU.vPrgBankReg >= 0x74)
+ return FALSE;
+
+ /* Check if we're in RAM and the RAN flag is not set */
+ if(GSU.vPrgBankReg >= 0x70 && GSU.vPrgBankReg <= 0x73 && !(SCMR&(1<<3)) )
+ return FALSE;
+
+ /* If not, we're in ROM, so check if the RON flag is set */
+ if(!(SCMR&(1<<4)))
+ return FALSE;
+
+ return TRUE;
+}
+
+/* Execute until the next stop instruction */
+int FxEmulate(uint32 nInstructions)
+{
+ uint32 vCount;
+
+ /* Read registers and initialize GSU session */
+ fx_readRegisterSpace();
+
+ /* Check if the start address is valid */
+ if(!fx_checkStartAddress())
+ {
+ CF(G);
+ fx_writeRegisterSpace();
+#if 0
+ GSU.vIllegalAddress = (GSU.vPrgBankReg << 24) | R15;
+ return FX_ERROR_ILLEGAL_ADDRESS;
+#else
+ return 0;
+#endif
+ }
+
+ /* Execute GSU session */
+ CF(IRQ);
+
+ if(GSU.bBreakPoint)
+ vCount = fx_ppfFunctionTable[FX_FUNCTION_RUN_TO_BREAKPOINT](nInstructions);
+ else
+ vCount = fx_ppfFunctionTable[FX_FUNCTION_RUN](nInstructions);
+
+ /* Store GSU registers */
+ fx_writeRegisterSpace();
+
+ /* Check for error code */
+ if(GSU.vErrorCode)
+ return GSU.vErrorCode;
+ else
+ return vCount;
+}
+
+/* Breakpoints */
+void FxBreakPointSet(uint32 vAddress)
+{
+ GSU.bBreakPoint = TRUE;
+ GSU.vBreakPoint = USEX16(vAddress);
+}
+void FxBreakPointClear()
+{
+ GSU.bBreakPoint = FALSE;
+}
+
+/* Step by step execution */
+int FxStepOver(uint32 nInstructions)
+{
+ uint32 vCount;
+ fx_readRegisterSpace();
+
+ /* Check if the start address is valid */
+ if(!fx_checkStartAddress())
+ {
+ CF(G);
+#if 0
+ GSU.vIllegalAddress = (GSU.vPrgBankReg << 24) | R15;
+ return FX_ERROR_ILLEGAL_ADDRESS;
+#else
+ return 0;
+#endif
+ }
+
+ if( PIPE >= 0xf0 )
+ GSU.vStepPoint = USEX16(R15+3);
+ else if( (PIPE >= 0x05 && PIPE <= 0x0f) || (PIPE >= 0xa0 && PIPE <= 0xaf) )
+ GSU.vStepPoint = USEX16(R15+2);
+ else
+ GSU.vStepPoint = USEX16(R15+1);
+ vCount = fx_ppfFunctionTable[FX_FUNCTION_STEP_OVER](nInstructions);
+ fx_writeRegisterSpace();
+ if(GSU.vErrorCode)
+ return GSU.vErrorCode;
+ else
+ return vCount;
+}
+
+/* Errors */
+int FxGetErrorCode()
+{
+ return GSU.vErrorCode;
+}
+
+int FxGetIllegalAddress()
+{
+ return GSU.vIllegalAddress;
+}
+
+/* Access to internal registers */
+uint32 FxGetColorRegister()
+{
+ return GSU.vColorReg & 0xff;
+}
+
+uint32 FxGetPlotOptionRegister()
+{
+ return GSU.vPlotOptionReg & 0x1f;
+}
+
+uint32 FxGetSourceRegisterIndex()
+{
+ return GSU.pvSreg - GSU.avReg;
+}
+
+uint32 FxGetDestinationRegisterIndex()
+{
+ return GSU.pvDreg - GSU.avReg;
+}
+
+uint8 FxPipe()
+{
+ return GSU.vPipe;
+}
projects / drnoksnes / blobdiff