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Diffstat (limited to 'source/fxemu.c')
-rw-r--r-- | source/fxemu.c | 726 |
1 files changed, 726 insertions, 0 deletions
diff --git a/source/fxemu.c b/source/fxemu.c new file mode 100644 index 0000000..8dd7a15 --- /dev/null +++ b/source/fxemu.c @@ -0,0 +1,726 @@ +/******************************************************************************* + Snes9x - Portable Super Nintendo Entertainment System (TM) emulator. + + (c) Copyright 1996 - 2002 Gary Henderson (gary.henderson@ntlworld.com) and + Jerremy Koot (jkoot@snes9x.com) + + (c) Copyright 2001 - 2004 John Weidman (jweidman@slip.net) + + (c) Copyright 2002 - 2004 Brad Jorsch (anomie@users.sourceforge.net), + funkyass (funkyass@spam.shaw.ca), + Joel Yliluoma (http://iki.fi/bisqwit/) + Kris Bleakley (codeviolation@hotmail.com), + Matthew Kendora, + Nach (n-a-c-h@users.sourceforge.net), + Peter Bortas (peter@bortas.org) and + zones (kasumitokoduck@yahoo.com) + + C4 x86 assembler and some C emulation code + (c) Copyright 2000 - 2003 zsKnight (zsknight@zsnes.com), + _Demo_ (_demo_@zsnes.com), and Nach + + C4 C++ code + (c) Copyright 2003 Brad Jorsch + + DSP-1 emulator code + (c) Copyright 1998 - 2004 Ivar (ivar@snes9x.com), _Demo_, Gary Henderson, + John Weidman, neviksti (neviksti@hotmail.com), + Kris Bleakley, Andreas Naive + + DSP-2 emulator code + (c) Copyright 2003 Kris Bleakley, John Weidman, neviksti, Matthew Kendora, and + Lord Nightmare (lord_nightmare@users.sourceforge.net + + OBC1 emulator code + (c) Copyright 2001 - 2004 zsKnight, pagefault (pagefault@zsnes.com) and + Kris Bleakley + Ported from x86 assembler to C by sanmaiwashi + + SPC7110 and RTC C++ emulator code + (c) Copyright 2002 Matthew Kendora with research by + zsKnight, John Weidman, and Dark Force + + S-DD1 C emulator code + (c) Copyright 2003 Brad Jorsch with research by + Andreas Naive and John Weidman + + S-RTC C emulator code + (c) Copyright 2001 John Weidman + + ST010 C++ emulator code + (c) Copyright 2003 Feather, Kris Bleakley, John Weidman and Matthew Kendora + + Super FX x86 assembler emulator code + (c) Copyright 1998 - 2003 zsKnight, _Demo_, and pagefault + + Super FX C emulator code + (c) Copyright 1997 - 1999 Ivar, Gary Henderson and John Weidman + + + SH assembler code partly based on x86 assembler code + (c) Copyright 2002 - 2004 Marcus Comstedt (marcus@mc.pp.se) + + + Specific ports 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 = FxRegs_s_null; + +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; +} + + +void fx_updateRamBank(uint8 Byte) +{ + // Update BankReg and Bank pointer + GSU.vRamBankReg = (uint32)Byte & (FX_RAM_BANKS-1); + GSU.pvRamBank = GSU.apvRamBank[Byte & 0x3]; +} + + +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_dirtySCBR() +{ + GSU.vSCBRDirty = TRUE; +} + +void fx_computeScreenPointers () +{ + if (GSU.vMode != GSU.vPrevMode || + GSU.vPrevScreenHeight != GSU.vScreenHeight || + GSU.vSCBRDirty) + { + int i; + + GSU.vSCBRDirty = FALSE; + + /* 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; +} + |