Supermodel/Src/CPU/68K/68K.cpp
2018-01-22 18:27:51 +00:00

450 lines
13 KiB
C++

/**
** Supermodel
** A Sega Model 3 Arcade Emulator.
** Copyright 2011 Bart Trzynadlowski, Nik Henson
**
** This file is part of Supermodel.
**
** Supermodel is free software: you can redistribute it and/or modify it under
** the terms of the GNU General Public License as published by the Free
** Software Foundation, either version 3 of the License, or (at your option)
** any later version.
**
** Supermodel is distributed in the hope that it will be useful, but WITHOUT
** ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
** FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
** more details.
**
** You should have received a copy of the GNU General Public License along
** with Supermodel. If not, see <http://www.gnu.org/licenses/>.
**/
/*
* 68K.cpp
*
* 68K CPU interface. This is presently just a wrapper for the Musashi 68K core
* and therefore, only a single CPU is supported. In the future, we may want to
* add in another 68K core (eg., Turbo68K, A68K, or a recompiler).
*
* To-Do List
* ----------
* - Registers may not completely describe the 68K state. Musashi also has
* additional CPU state information in the context that its MAME interface
* accesses (interrupts pending, halted status, etc.)
*/
#include "Supermodel.h"
#include "Musashi/m68k.h" // Musashi 68K core
/******************************************************************************
Internal Context
An active context must be mapped before calling M68K interface functions. Only
the bus and IRQ handlers are copied here; the CPU context is passed directly
to Musashi.
******************************************************************************/
// Bus
static IBus *s_Bus = NULL;
#ifdef SUPERMODEL_DEBUGGER
// Debugger
static Debugger::CMusashi68KDebug *s_Debug = NULL;
#endif
// IRQ callback
static int (*IRQAck)(int nIRQ) = NULL;
// Cycles remaining in timeslice
static int s_lastCycles;
/******************************************************************************
68K Interface
******************************************************************************/
// CPU state
UINT32 M68KGetARegister(int n)
{
m68k_register_t r;
switch (n)
{
case 0: r = M68K_REG_A0; break;
case 1: r = M68K_REG_A1; break;
case 2: r = M68K_REG_A2; break;
case 3: r = M68K_REG_A3; break;
case 4: r = M68K_REG_A4; break;
case 5: r = M68K_REG_A5; break;
case 6: r = M68K_REG_A6; break;
case 7: r = M68K_REG_A7; break;
default: r = M68K_REG_A7; break;
}
return m68k_get_reg(NULL, r);
}
UINT32 M68KGetDRegister(int n)
{
m68k_register_t r;
switch (n)
{
case 0: r = M68K_REG_D0; break;
case 1: r = M68K_REG_D1; break;
case 2: r = M68K_REG_D2; break;
case 3: r = M68K_REG_D3; break;
case 4: r = M68K_REG_D4; break;
case 5: r = M68K_REG_D5; break;
case 6: r = M68K_REG_D6; break;
case 7: r = M68K_REG_D7; break;
default: r = M68K_REG_D7; break;
}
return m68k_get_reg(NULL, r);
}
UINT32 M68KGetPC(void)
{
return m68k_get_reg(NULL, M68K_REG_PC);
}
void M68KSaveState(CBlockFile *StateFile, const char *name)
{
StateFile->NewBlock(name, __FILE__);
/*
* Rather than writing the context directly, the get/set register
* functions are used, ensuring that all context members are packed/
* unpacked correctly.
*
* Note: Some of these are undoubtedly 68010 or 68020 registers and not
* really necessary. But if the layout is changed now, the save state
* version has to be changed, so don't do it!
*/
UINT32 data[34];
m68ki_cpu_core Ctx;
m68k_get_context(&Ctx);
data[0] = Ctx.int_level;
data[1] = Ctx.int_cycles;
data[2] = Ctx.stopped;
data[3] = m68k_get_reg(NULL, M68K_REG_D0);
data[4] = m68k_get_reg(NULL, M68K_REG_D1);
data[5] = m68k_get_reg(NULL, M68K_REG_D2);
data[6] = m68k_get_reg(NULL, M68K_REG_D3);
data[7] = m68k_get_reg(NULL, M68K_REG_D4);
data[8] = m68k_get_reg(NULL, M68K_REG_D5);
data[9] = m68k_get_reg(NULL, M68K_REG_D6);
data[10] = m68k_get_reg(NULL, M68K_REG_D7);
data[11] = m68k_get_reg(NULL, M68K_REG_A0);
data[12] = m68k_get_reg(NULL, M68K_REG_A1);
data[13] = m68k_get_reg(NULL, M68K_REG_A2);
data[14] = m68k_get_reg(NULL, M68K_REG_A3);
data[15] = m68k_get_reg(NULL, M68K_REG_A4);
data[16] = m68k_get_reg(NULL, M68K_REG_A5);
data[17] = m68k_get_reg(NULL, M68K_REG_A6);
data[18] = m68k_get_reg(NULL, M68K_REG_A7);
data[19] = m68k_get_reg(NULL, M68K_REG_PC);
data[20] = m68k_get_reg(NULL, M68K_REG_SR);
data[21] = m68k_get_reg(NULL, M68K_REG_SP);
data[22] = m68k_get_reg(NULL, M68K_REG_USP);
data[23] = m68k_get_reg(NULL, M68K_REG_ISP);
data[24] = m68k_get_reg(NULL, M68K_REG_MSP);
data[25] = m68k_get_reg(NULL, M68K_REG_SFC);
data[26] = m68k_get_reg(NULL, M68K_REG_DFC);
data[27] = m68k_get_reg(NULL, M68K_REG_VBR);
data[28] = m68k_get_reg(NULL, M68K_REG_CACR);
data[29] = m68k_get_reg(NULL, M68K_REG_CAAR);
data[30] = m68k_get_reg(NULL, M68K_REG_PREF_ADDR);
data[31] = m68k_get_reg(NULL, M68K_REG_PREF_DATA);
data[32] = m68k_get_reg(NULL, M68K_REG_PPC);
data[33] = m68k_get_reg(NULL, M68K_REG_IR);
StateFile->Write(data, sizeof(data));
}
void M68KLoadState(CBlockFile *StateFile, const char *name)
{
if (OKAY != StateFile->FindBlock(name))
{
ErrorLog("Unable to load 68K state. Save state file is corrupt.");
return;
}
UINT32 data[34];
m68ki_cpu_core Ctx;
StateFile->Read(data, sizeof(data));
// These must be set first, to ensure another contexts' IRQs aren't active when PC is changed
m68k_get_context(&Ctx);
Ctx.int_level = data[0];
Ctx.int_cycles = data[1];
Ctx.stopped = data[2];
m68k_set_context(&Ctx); // write them back to context
m68k_set_reg(M68K_REG_D0, data[3]);
m68k_set_reg(M68K_REG_D1, data[4]);
m68k_set_reg(M68K_REG_D2, data[5]);
m68k_set_reg(M68K_REG_D3, data[6]);
m68k_set_reg(M68K_REG_D4, data[7]);
m68k_set_reg(M68K_REG_D5, data[8]);
m68k_set_reg(M68K_REG_D6, data[9]);
m68k_set_reg(M68K_REG_D7, data[10]);
m68k_set_reg(M68K_REG_A0, data[11]);
m68k_set_reg(M68K_REG_A1, data[12]);
m68k_set_reg(M68K_REG_A2, data[13]);
m68k_set_reg(M68K_REG_A3, data[14]);
m68k_set_reg(M68K_REG_A4, data[15]);
m68k_set_reg(M68K_REG_A5, data[16]);
m68k_set_reg(M68K_REG_A6, data[17]);
m68k_set_reg(M68K_REG_A7, data[18]);
m68k_set_reg(M68K_REG_PC, data[19]);
m68k_set_reg(M68K_REG_SR, data[20]);
m68k_set_reg(M68K_REG_SP, data[21]);
m68k_set_reg(M68K_REG_USP, data[22]);
m68k_set_reg(M68K_REG_ISP, data[23]);
m68k_set_reg(M68K_REG_MSP, data[24]);
m68k_set_reg(M68K_REG_SFC, data[25]);
m68k_set_reg(M68K_REG_DFC, data[26]);
m68k_set_reg(M68K_REG_VBR, data[27]);
m68k_set_reg(M68K_REG_CACR, data[28]);
m68k_set_reg(M68K_REG_CAAR, data[29]);
m68k_set_reg(M68K_REG_PREF_ADDR, data[30]);
m68k_set_reg(M68K_REG_PREF_DATA, data[31]);
m68k_set_reg(M68K_REG_PPC, data[32]);
m68k_set_reg(M68K_REG_IR, data[33]);
}
// Emulation functions
void M68KSetIRQ(int irqLevel)
{
m68k_set_irq(irqLevel);
}
int M68KRun(int numCycles)
{
#ifdef SUPERMODEL_DEBUGGER
if (s_Debug != NULL)
{
s_Debug->CPUActive();
s_lastCycles += numCycles;
}
#endif // SUPERMODEL_DEBUGGER
int doneCycles = m68k_execute(numCycles);
#ifdef SUPERMODEL_DEBUGGER
if (s_Debug != NULL)
{
s_Debug->CPUInactive();
s_lastCycles -= m68k_cycles_remaining();
}
#endif // SUPERMODEL_DEBUGGER
return doneCycles;
}
void M68KReset(void)
{
m68k_pulse_reset();
#ifdef SUPERMODEL_DEBUGGER
s_lastCycles = 0;
#endif
DebugLog("68K reset\n");
}
// Callback setup
void M68KSetIRQCallback(int (*F)(int nIRQ))
{
IRQAck = F;
}
void M68KAttachBus(IBus *BusPtr)
{
s_Bus = BusPtr;
DebugLog("Attached bus to 68K\n");
}
// Context switching
void M68KGetContext(M68KCtx *Dest)
{
Dest->IRQAck = IRQAck;
Dest->Bus = s_Bus;
#ifdef SUPERMODEL_DEBUGGER
Dest->Debug = s_Debug;
#endif // SUPERMODEL_DEBUGGER
m68k_get_context(&(Dest->musashiCtx));
}
void M68KSetContext(M68KCtx *Src)
{
IRQAck = Src->IRQAck;
s_Bus = Src->Bus;
#ifdef SUPERMODEL_DEBUGGER
s_Debug = Src->Debug;
#endif // SUPERMODEL_DEBUGGER
m68k_set_context(&(Src->musashiCtx));
}
// One-time initialization
bool M68KInit(void)
{
m68k_init();
m68k_set_cpu_type(M68K_CPU_TYPE_68000);
m68k_set_int_ack_callback(M68KIRQCallback);
s_Bus = NULL;
#ifdef SUPERMODEL_DEBUGGER
s_Debug = NULL;
#endif // SUPERMODEL_DEBUGGER
DebugLog("Initialized 68K\n");
return OKAY;
}
#ifdef SUPERMODEL_DEBUGGER
UINT32 M68KGetRegister(M68KCtx *Src, unsigned reg)
{
switch (reg)
{
case DBG68K_REG_PC: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_PC);
case DBG68K_REG_SR: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_SR);
case DBG68K_REG_SP: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_SP);
case DBG68K_REG_D0: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_D0);
case DBG68K_REG_D1: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_D1);
case DBG68K_REG_D2: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_D2);
case DBG68K_REG_D3: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_D3);
case DBG68K_REG_D4: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_D4);
case DBG68K_REG_D5: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_D5);
case DBG68K_REG_D6: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_D6);
case DBG68K_REG_D7: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_D7);
case DBG68K_REG_A0: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_A0);
case DBG68K_REG_A1: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_A1);
case DBG68K_REG_A2: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_A2);
case DBG68K_REG_A3: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_A3);
case DBG68K_REG_A4: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_A4);
case DBG68K_REG_A5: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_A5);
case DBG68K_REG_A6: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_A6);
case DBG68K_REG_A7: return m68k_get_reg(&(Src->musashiCtx), M68K_REG_A7);
default: return 0;
}
}
UINT32 M68KSetRegister(M68KCtx *Src, unsigned reg, UINT32 val)
{
switch (reg)
{
case DBG68K_REG_PC: m68k_set_reg(M68K_REG_PC, val); return true;
case DBG68K_REG_SR: m68k_set_reg(M68K_REG_SR, val); return true;
case DBG68K_REG_SP: m68k_set_reg(M68K_REG_SP, val); return true;
case DBG68K_REG_D0: m68k_set_reg(M68K_REG_D0, val); return true;
case DBG68K_REG_D1: m68k_set_reg(M68K_REG_D1, val); return true;
case DBG68K_REG_D2: m68k_set_reg(M68K_REG_D2, val); return true;
case DBG68K_REG_D3: m68k_set_reg(M68K_REG_D3, val); return true;
case DBG68K_REG_D4: m68k_set_reg(M68K_REG_D4, val); return true;
case DBG68K_REG_D5: m68k_set_reg(M68K_REG_D5, val); return true;
case DBG68K_REG_D6: m68k_set_reg(M68K_REG_D6, val); return true;
case DBG68K_REG_D7: m68k_set_reg(M68K_REG_D7, val); return true;
case DBG68K_REG_A0: m68k_set_reg(M68K_REG_A0, val); return true;
case DBG68K_REG_A1: m68k_set_reg(M68K_REG_A1, val); return true;
case DBG68K_REG_A2: m68k_set_reg(M68K_REG_A2, val); return true;
case DBG68K_REG_A3: m68k_set_reg(M68K_REG_A3, val); return true;
case DBG68K_REG_A4: m68k_set_reg(M68K_REG_A4, val); return true;
case DBG68K_REG_A5: m68k_set_reg(M68K_REG_A5, val); return true;
case DBG68K_REG_A6: m68k_set_reg(M68K_REG_A6, val); return true;
case DBG68K_REG_A7: m68k_set_reg(M68K_REG_A7, val); return true;
default: return false;
}
}
#endif // SUPERMODEL_DEBUGGER
/******************************************************************************
Musashi 68K Handlers
Musashi/m68kconf.h has been configured to call these directly.
******************************************************************************/
extern "C" {
#ifdef SUPERMODEL_DEBUGGER
void M68KDebugCallback()
{
if (s_Debug != NULL)
{
UINT32 pc = m68k_get_reg(NULL, M68K_REG_PC);
UINT32 opcode = s_Bus->Read16(pc);
s_Debug->CPUExecute(pc, opcode, s_lastCycles - m68k_cycles_remaining());
s_lastCycles = m68k_cycles_remaining();
}
}
#endif // SUPERMODEL_DEBUGGER
int M68KIRQCallback(int nIRQ)
{
#ifdef SUPERMODEL_DEBUGGER
if (s_Debug != NULL)
{
s_Debug->CPUException(25);
s_Debug->CPUInterrupt(nIRQ - 1);
}
#endif // SUPERMODEL_DEBUGGER
if (NULL == IRQAck) // no handler, use default behavior
{
m68k_set_irq(0); // clear line
return M68K_IRQ_AUTOVECTOR;
}
else
return IRQAck(nIRQ);
}
unsigned int FASTCALL M68KFetch8(unsigned int a)
{
return s_Bus->Read8(a);
}
unsigned int FASTCALL M68KFetch16(unsigned int a)
{
return s_Bus->Read16(a);
}
unsigned int FASTCALL M68KFetch32(unsigned int a)
{
return s_Bus->Read32(a);
}
unsigned int FASTCALL M68KRead8(unsigned int a)
{
return s_Bus->Read8(a);
}
unsigned int FASTCALL M68KRead16(unsigned int a)
{
return s_Bus->Read16(a);
}
unsigned int FASTCALL M68KRead32(unsigned int a)
{
return s_Bus->Read32(a);
}
void FASTCALL M68KWrite8(unsigned int a, unsigned int d)
{
s_Bus->Write8(a, d);
}
void FASTCALL M68KWrite16(unsigned int a, unsigned int d)
{
s_Bus->Write16(a, d);
}
void FASTCALL M68KWrite32(unsigned int a, unsigned int d)
{
s_Bus->Write32(a, d);
}
} // extern "C"