/*====================================================================

   filename:     gdsp_interpreter.cpp
   project:      GCemu
   created:      2004-6-18
   mail:		  duddie@walla.com

   Copyright (c) 2005 Duddie & Tratax

   This program 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 2
   of the License, or (at your option) any later version.

   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

   ====================================================================*/

#include "Common.h"
#include "Hash.h"
#include "Thread.h"
#include "DSPCore.h"
#include "DSPEmitter.h"
#include "DSPHost.h"
#include "DSPAnalyzer.h"
#include "MemoryUtil.h"
#include "FileUtil.h"

#include "DSPHWInterface.h"
#include "DSPIntUtil.h"

SDSP g_dsp;
DSPBreakpoints dsp_breakpoints;
DSPCoreState core_state = DSPCORE_STOP;
u16 cyclesLeft = 0;
bool init_hax = false;
DSPEmitter *dspjit = NULL;
Common::Event step_event;

static bool LoadRom(const char *fname, int size_in_words, u16 *rom)
{
	File::IOFile pFile(fname, "rb");
	const size_t size_in_bytes = size_in_words * sizeof(u16);
	if (pFile)
	{
		pFile.ReadArray(rom, size_in_words);
		pFile.Close();
	
		// Byteswap the rom.
		for (int i = 0; i < size_in_words; i++)
			rom[i] = Common::swap16(rom[i]);

		// Always keep ROMs write protected.
		WriteProtectMemory(rom, size_in_bytes, false);
		return true;
	}

	PanicAlertT(
		"Failed to load DSP ROM:\t%s\n"
		"\n"
		"This file is required to use DSP LLE.\n"
		"It is not included with Dolphin as it contains copyrighted data.\n"
		"Use DSPSpy to dump the file from your physical console.\n"
		"\n"
		"You may use the DSP HLE engine which does not require ROM dumps.\n"
		"(Choose it from the \"Audio\" tab of the configuration dialog.)", fname);
	return false;
}

// Returns false iff the hash fails and the user hits "Yes"
static bool VerifyRoms(const char *irom_filename, const char *coef_filename)
{
	static const u32 hash[] = { 0x66f334fe, 0xf3b93527 };
	static const u32 hash_mini[] = { 0x9c8f593c, 0x10000001 };
	static const int size[] = { DSP_IROM_BYTE_SIZE, DSP_COEF_BYTE_SIZE };
	const u16 *data[] = { g_dsp.irom, g_dsp.coef };
	u32 h = 0;
	u8 count = 0;

	for (int i = 0; i < 2; i++)
	{
		h = HashAdler32((u8*)data[i], size[i]);

		if (h == hash_mini[i])
		{
			count++;
		}
		else if (h != hash[i])
		{
			if (AskYesNoT("%s has an incorrect hash.\n"
				"Would you like to stop now to fix the problem?\n"
				"If you select \"No\", audio will be garbled.",
				(i == 0) ? irom_filename : coef_filename))
				return false;
		}
	}

	if (count == 2)
	{
		PanicAlertT("You are using free dsp roms made by Dolphin Team.\n"
					"Only Zelda ucode games will work correctly with them.\n");
	}

	return true;
}

static void DSPCore_FreeMemoryPages()
{
	FreeMemoryPages(g_dsp.irom, DSP_IROM_BYTE_SIZE);
	FreeMemoryPages(g_dsp.iram, DSP_IRAM_BYTE_SIZE);
	FreeMemoryPages(g_dsp.dram, DSP_DRAM_BYTE_SIZE);
	FreeMemoryPages(g_dsp.coef, DSP_COEF_BYTE_SIZE);
}

bool DSPCore_Init(const char *irom_filename, const char *coef_filename,
				  bool bUsingJIT)
{
	g_dsp.step_counter = 0;
	cyclesLeft = 0;
	dspjit = NULL;
	
	g_dsp.irom = (u16*)AllocateMemoryPages(DSP_IROM_BYTE_SIZE);
	g_dsp.iram = (u16*)AllocateMemoryPages(DSP_IRAM_BYTE_SIZE);
	g_dsp.dram = (u16*)AllocateMemoryPages(DSP_DRAM_BYTE_SIZE);
	g_dsp.coef = (u16*)AllocateMemoryPages(DSP_COEF_BYTE_SIZE);

	// Fill roms with zeros.
	memset(g_dsp.irom, 0, DSP_IROM_BYTE_SIZE);
	memset(g_dsp.coef, 0, DSP_COEF_BYTE_SIZE);

	// Try to load real ROM contents.
	if (!LoadRom(irom_filename, DSP_IROM_SIZE, g_dsp.irom) ||
			!LoadRom(coef_filename, DSP_COEF_SIZE, g_dsp.coef) ||
			!VerifyRoms(irom_filename, coef_filename))
	{
		DSPCore_FreeMemoryPages();
		return false;
	}

	memset(&g_dsp.r,0,sizeof(g_dsp.r));

	for (int i = 0; i < 4; i++)
	{
		g_dsp.reg_stack_ptr[i] = 0;
		for (int j = 0; j < DSP_STACK_DEPTH; j++)
		{
			g_dsp.reg_stack[i][j] = 0;
		}
	}

	// Fill IRAM with HALT opcodes.
	for (int i = 0; i < DSP_IRAM_SIZE; i++)
	{
		g_dsp.iram[i] = 0x0021; // HALT opcode
	}

	// Just zero out DRAM.
	for (int i = 0; i < DSP_DRAM_SIZE; i++)
	{
		g_dsp.dram[i] = 0;
	}

	// Copied from a real console after the custom UCode has been loaded.
	// These are the indexing wrapping registers.
	g_dsp.r.wr[0] = 0xffff;
	g_dsp.r.wr[1] = 0xffff;
	g_dsp.r.wr[2] = 0xffff;
	g_dsp.r.wr[3] = 0xffff;

	g_dsp.r.sr |= SR_INT_ENABLE;
	g_dsp.r.sr |= SR_EXT_INT_ENABLE;

	g_dsp.cr = 0x804;
	gdsp_ifx_init();
	// Mostly keep IRAM write protected. We unprotect only when DMA-ing
	// in new ucodes.
	WriteProtectMemory(g_dsp.iram, DSP_IRAM_BYTE_SIZE, false);

	// Initialize JIT, if necessary
	if(bUsingJIT) 
		dspjit = new DSPEmitter();

	core_state = DSPCORE_RUNNING;
	return true;
}

void DSPCore_Shutdown()
{
	if (core_state == DSPCORE_STOP)
		return;

	core_state = DSPCORE_STOP;

	if(dspjit) {
		delete dspjit;
		dspjit = NULL;
	}
	DSPCore_FreeMemoryPages();
}

void DSPCore_Reset()
{
    g_dsp.pc = DSP_RESET_VECTOR;

	g_dsp.r.wr[0] = 0xffff;
	g_dsp.r.wr[1] = 0xffff;
	g_dsp.r.wr[2] = 0xffff;
	g_dsp.r.wr[3] = 0xffff;

	DSPAnalyzer::Analyze();
}

void DSPCore_SetException(u8 level)
{
	g_dsp.exceptions |= 1 << level;
}

// Notify that an external interrupt is pending (used by thread mode)
void DSPCore_SetExternalInterrupt(bool val)
{
	g_dsp.external_interrupt_waiting = val;
}

// Coming from the CPU
void DSPCore_CheckExternalInterrupt()
{
	if (! dsp_SR_is_flag_set(SR_EXT_INT_ENABLE))
		return;

	// Signal the SPU about new mail
	DSPCore_SetException(EXP_INT);
	
	g_dsp.cr &= ~CR_EXTERNAL_INT;
}


void DSPCore_CheckExceptions()
{
	// Early out to skip the loop in the common case.
	if (g_dsp.exceptions == 0)
		return;

	for (int i = 7; i > 0; i--) {
		// Seems exp int are not masked by sr_int_enable
		if (g_dsp.exceptions & (1 << i)) {
			if (dsp_SR_is_flag_set(SR_INT_ENABLE) || (i == EXP_INT)) {

				// store pc and sr until RTI
				dsp_reg_store_stack(DSP_STACK_C, g_dsp.pc);
				dsp_reg_store_stack(DSP_STACK_D, g_dsp.r.sr);

				g_dsp.pc = i * 2;
				g_dsp.exceptions &= ~(1 << i);
				if (i == 7)
					g_dsp.r.sr &= ~SR_EXT_INT_ENABLE;
				else
					g_dsp.r.sr &= ~SR_INT_ENABLE;
				break;
			} else {
#if defined(_DEBUG) || defined(DEBUGFAST)
				ERROR_LOG(DSPLLE, "Firing exception %d failed", i);
#endif
			}
		}
	}
}

// Delegate to JIT or interpreter as appropriate.
// Handle state changes and stepping.
int DSPCore_RunCycles(int cycles)
{
	if (dspjit)
	{
		if (g_dsp.external_interrupt_waiting)
		{
			DSPCore_CheckExternalInterrupt();
			DSPCore_CheckExceptions();
			DSPCore_SetExternalInterrupt(false);
		}

		cyclesLeft = cycles;
		DSPCompiledCode pExecAddr = (DSPCompiledCode)dspjit->enterDispatcher;
		pExecAddr();

		if (g_dsp.reset_dspjit_codespace)
			dspjit->ClearIRAMandDSPJITCodespaceReset();

		return cyclesLeft;
	}

	while (cycles > 0)
	{
		switch (core_state)
		{
		case DSPCORE_RUNNING:
			// Seems to slow things down
#if defined(_DEBUG) || defined(DEBUGFAST)
			cycles = DSPInterpreter::RunCyclesDebug(cycles);
#else
			cycles = DSPInterpreter::RunCycles(cycles);
#endif
			break;

		case DSPCORE_STEPPING:
			step_event.Wait();
			if (core_state != DSPCORE_STEPPING)
				continue;

			DSPInterpreter::Step();
			cycles--;

			DSPHost_UpdateDebugger();
			break;
		case DSPCORE_STOP:
			break;
		}
	}
	return cycles;
}

void DSPCore_SetState(DSPCoreState new_state)
{
	core_state = new_state;
	// kick the event, in case we are waiting
	if (new_state == DSPCORE_RUNNING)
		step_event.Set();
	// Sleep(10);
	DSPHost_UpdateDebugger();
}

DSPCoreState DSPCore_GetState()
{
	return core_state;
}

void DSPCore_Step()
{
	if (core_state == DSPCORE_STEPPING)
		step_event.Set();
}

void CompileCurrent()
{
	dspjit->Compile(g_dsp.pc);

	bool retry = true;

	while (retry)
	{
		retry = false;
		for(u16 i = 0x0000; i < 0xffff; ++i)
		{
			if (!dspjit->unresolvedJumps[i].empty())
			{
				u16 addrToCompile = dspjit->unresolvedJumps[i].front();
				dspjit->Compile(addrToCompile);
				if (!dspjit->unresolvedJumps[i].empty())
					retry = true;
			}
		}
	}
}

u16 DSPCore_ReadRegister(int reg) {
	switch(reg) {
	case DSP_REG_AR0:
	case DSP_REG_AR1:
	case DSP_REG_AR2:
	case DSP_REG_AR3:
		return g_dsp.r.ar[reg - DSP_REG_AR0];
	case DSP_REG_IX0:
	case DSP_REG_IX1:
	case DSP_REG_IX2:
	case DSP_REG_IX3:
		return g_dsp.r.ix[reg - DSP_REG_IX0];
	case DSP_REG_WR0:
	case DSP_REG_WR1:
	case DSP_REG_WR2:
	case DSP_REG_WR3:
		return g_dsp.r.wr[reg - DSP_REG_WR0];
	case DSP_REG_ST0:
	case DSP_REG_ST1:
	case DSP_REG_ST2:
	case DSP_REG_ST3:
		return g_dsp.r.st[reg - DSP_REG_ST0];
	case DSP_REG_ACH0:
	case DSP_REG_ACH1:
		return g_dsp.r.ac[reg - DSP_REG_ACH0].h;
	case DSP_REG_CR:     return g_dsp.r.cr;
	case DSP_REG_SR:     return g_dsp.r.sr;
	case DSP_REG_PRODL:  return g_dsp.r.prod.l;
	case DSP_REG_PRODM:  return g_dsp.r.prod.m;
	case DSP_REG_PRODH:  return g_dsp.r.prod.h;
	case DSP_REG_PRODM2: return g_dsp.r.prod.m2;
	case DSP_REG_AXL0:
	case DSP_REG_AXL1:
		return g_dsp.r.ax[reg - DSP_REG_AXL0].l;
	case DSP_REG_AXH0:
	case DSP_REG_AXH1:
		return g_dsp.r.ax[reg - DSP_REG_AXH0].h;
	case DSP_REG_ACL0:
	case DSP_REG_ACL1:
		return g_dsp.r.ac[reg - DSP_REG_ACL0].l;
	case DSP_REG_ACM0:
	case DSP_REG_ACM1:
		return g_dsp.r.ac[reg - DSP_REG_ACM0].m;
	default:
		_assert_msg_(DSP_CORE, 0, "cannot happen");
		return 0;
	}
}

void DSPCore_WriteRegister(int reg, u16 val) {
	switch(reg) {
	case DSP_REG_AR0:
	case DSP_REG_AR1:
	case DSP_REG_AR2:
	case DSP_REG_AR3:
		g_dsp.r.ar[reg - DSP_REG_AR0] = val;
		break;
	case DSP_REG_IX0:
	case DSP_REG_IX1:
	case DSP_REG_IX2:
	case DSP_REG_IX3:
		g_dsp.r.ix[reg - DSP_REG_IX0] = val;
		break;
	case DSP_REG_WR0:
	case DSP_REG_WR1:
	case DSP_REG_WR2:
	case DSP_REG_WR3:
		g_dsp.r.wr[reg - DSP_REG_WR0] = val;
		break;
	case DSP_REG_ST0:
	case DSP_REG_ST1:
	case DSP_REG_ST2:
	case DSP_REG_ST3:
		g_dsp.r.st[reg - DSP_REG_ST0] = val;
		break;
	case DSP_REG_ACH0:
	case DSP_REG_ACH1:
		g_dsp.r.ac[reg - DSP_REG_ACH0].h = val;
		break;
	case DSP_REG_CR:     g_dsp.r.cr = val; break;
	case DSP_REG_SR:     g_dsp.r.sr = val; break;
	case DSP_REG_PRODL:  g_dsp.r.prod.l = val; break;
	case DSP_REG_PRODM:  g_dsp.r.prod.m = val; break;
	case DSP_REG_PRODH:  g_dsp.r.prod.h = val; break;
	case DSP_REG_PRODM2: g_dsp.r.prod.m2 = val; break;
	case DSP_REG_AXL0:
	case DSP_REG_AXL1:
		g_dsp.r.ax[reg - DSP_REG_AXL0].l = val;
		break;
	case DSP_REG_AXH0:
	case DSP_REG_AXH1:
		g_dsp.r.ax[reg - DSP_REG_AXH0].h = val;
		break;
	case DSP_REG_ACL0:
	case DSP_REG_ACL1:
		g_dsp.r.ac[reg - DSP_REG_ACL0].l = val;
		break;
	case DSP_REG_ACM0:
	case DSP_REG_ACM1:
		g_dsp.r.ac[reg - DSP_REG_ACM0].m = val;
		break;
	}
}
