Project64-Legacy/FlashRam.c

/*
 * Project 64 - A Nintendo 64 emulator.
 *
 * (c) Copyright 2001 zilmar (zilmar@emulation64.com) and
 * Jabo (jabo@emulation64.com).
 *
 * pj64 homepage: www.pj64.net
 *
 * Permission to use, copy, modify and distribute Project64 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.
 *
 * Project64 is freeware for PERSONAL USE only. Commercial users should
 * seek permission of the copyright holders first. Commercial use includes
 * charging money for Project64 or software derived from Project64.
 *
 * The copyright holders request that bug fixes and improvements to the code
 * should be forwarded to them so if they want them.
 *
 */

#include <windows.h>
#include <stdio.h>
#include "main.h"
#include "CPU.h"

typedef enum TFlashRam_Modes {
	FLASHRAM_MODE_NOPES = 0,
	FLASHRAM_MODE_ERASE = 1,
	FLASHRAM_MODE_WRITE,
	FLASHRAM_MODE_READ,
	FLASHRAM_MODE_STATUS,
};

BOOL LoadFlashram(void);

DWORD FlashRAM_Offset, FlashFlag = FLASHRAM_MODE_NOPES;
static HANDLE hFlashRamFile = NULL;
BYTE* FlashRamPointer;
QWORD FlashStatus = 0;

void DmaFromFlashram(BYTE* dest, int StartOffset, int len) {
	BYTE FlipBuffer[0x10000];
	DWORD dwRead, count;

	switch (FlashFlag) {
	case FLASHRAM_MODE_READ:
		if (hFlashRamFile == NULL) {
			if (!LoadFlashram()) { return; }
		}
		if (len > 0x10000) {
			if (ShowDebugMessages)
				DisplayError("DmaFromFlashram FlipBuffer to small (len: %d)", len);
			len = 0x10000;
		}
		if ((len & 3) != 0) {
			if (ShowDebugMessages)
				DisplayError("Unaligned flash ram read ???");
			return;
		}
		memset(FlipBuffer, 0, sizeof(FlipBuffer));
		StartOffset = StartOffset << 1;
		SetFilePointer(hFlashRamFile, StartOffset, NULL, FILE_BEGIN);
		ReadFile(hFlashRamFile, FlipBuffer, len, &dwRead, NULL);
		for (count = dwRead; (int)count < len; count++) {
			FlipBuffer[count] = 0xFF;
		}
		_asm {
			mov edi, dest
			lea ecx, [FlipBuffer]
			mov edx, 0
			mov ebx, len

			memcpyloop :
			mov eax, dword ptr[ecx + edx]
				; bswap eax
				mov  dword ptr[edi + edx], eax
				add edx, 4
				cmp edx, ebx
				jb memcpyloop
		}
		break;
	case FLASHRAM_MODE_STATUS:
		if (StartOffset != 0 && len != 8) {
			if (ShowDebugMessages)
				DisplayError("Reading flashstatus not being handled correctly\nStart: %X len: %X", StartOffset, len);
		}
		*((DWORD*)(dest)) = (DWORD)(FlashStatus >> 32);
		*((DWORD*)(dest)+1) = (DWORD)(FlashStatus);
		break;
	default:
		if (ShowDebugMessages)
			DisplayError("DmaFromFlashram Start: %X, Offset: %X len: %X", dest - N64MEM, StartOffset, len);
	}
}

void DmaToFlashram(BYTE* Source, int StartOffset, int len) {
	switch (FlashFlag) {
	case FLASHRAM_MODE_WRITE:
		FlashRamPointer = Source;
		break;
	default:
		if (ShowDebugMessages)
			DisplayError("DmaToFlashram Start: %X, Offset: %X len: %X", Source - N64MEM, StartOffset, len);
	}
}

DWORD ReadFromFlashStatus(DWORD PAddr) {
	switch (PAddr) {
	case 0x08000000: return (DWORD)(FlashStatus >> 32);
	default:
		if (ShowDebugMessages)
			DisplayError("Reading from flash ram status (%X)", PAddr);
		break;
	}
	return (DWORD)(FlashStatus >> 32);
}

BOOL LoadFlashram(void) {
	char File[255], Directory[255];

	Settings_GetDirectory(AutoSaveDir, Directory, sizeof(Directory));
	sprintf(File, "%s%s.fla", Directory, RomFullName);

	hFlashRamFile = CreateFile(File, GENERIC_WRITE | GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_ALWAYS,
		FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS, NULL);
	if (hFlashRamFile == INVALID_HANDLE_VALUE) {
		switch (GetLastError()) {
		case ERROR_PATH_NOT_FOUND:
			CreateDirectory(Directory, NULL);
			hFlashRamFile = CreateFile(File, GENERIC_WRITE | GENERIC_READ, FILE_SHARE_READ,
				NULL, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS, NULL);
			if (hFlashRamFile == INVALID_HANDLE_VALUE) {
				DisplayError(GS(MSG_FAIL_OPEN_FLASH));
				return FALSE;
			}
			break;
		default:
			DisplayError(GS(MSG_FAIL_OPEN_FLASH));
			return FALSE;
		}
	}
	return TRUE;
}

void WriteToFlashCommand(DWORD FlashRAM_Command) {
	BYTE EmptyBlock[128];
	DWORD dwWritten;

	switch (FlashRAM_Command & 0xFF000000) {
	case 0xD2000000:
		switch (FlashFlag) {
		case FLASHRAM_MODE_NOPES: break;
		case FLASHRAM_MODE_READ: break;
		case FLASHRAM_MODE_STATUS: break;
		case FLASHRAM_MODE_ERASE:
			memset(EmptyBlock, 0xFF, sizeof(EmptyBlock));
			if (hFlashRamFile == NULL) {
				if (!LoadFlashram()) { return; }
			}
			SetFilePointer(hFlashRamFile, FlashRAM_Offset, NULL, FILE_BEGIN);
			WriteFile(hFlashRamFile, EmptyBlock, 128, &dwWritten, NULL);
			break;
		case FLASHRAM_MODE_WRITE:
			if (hFlashRamFile == NULL) {
				if (!LoadFlashram()) { return; }
			}
			{
				BYTE FlipBuffer[128];
				DWORD dwWritten;

				memset(FlipBuffer, 0, sizeof(FlipBuffer));
				_asm {
					lea edi, [FlipBuffer]
					mov ecx, FlashRamPointer
					mov edx, 0

					memcpyloop:
					mov eax, dword ptr[ecx + edx]
						; bswap eax
						mov  dword ptr[edi + edx], eax
						add edx, 4
						cmp edx, 128
						jb memcpyloop
				}

				SetFilePointer(hFlashRamFile, FlashRAM_Offset, NULL, FILE_BEGIN);
				WriteFile(hFlashRamFile, FlipBuffer, 128, &dwWritten, NULL);
			}
			break;
		default:
			DisplayError("Writing %X to flash ram command register\nFlashFlag: %d", FlashRAM_Command, FlashFlag);
		}
		FlashFlag = FLASHRAM_MODE_NOPES;
		break;
	case 0xE1000000:
		FlashFlag = FLASHRAM_MODE_STATUS;
		FlashStatus = 0x1111800100C20000;
		break;
	case 0xF0000000:
		FlashFlag = FLASHRAM_MODE_READ;
		FlashStatus = 0x11118004F0000000;
		break;
	case 0x4B000000:
		FlashRAM_Offset = (FlashRAM_Command & 0xffff) * 128;
		break;
	case 0x78000000:
		FlashFlag = FLASHRAM_MODE_ERASE;
		FlashStatus = 0x1111800800C20000;
		break;
	case 0xB4000000:
		FlashFlag = FLASHRAM_MODE_WRITE; //????
		break;
	case 0xA5000000:
		FlashRAM_Offset = (FlashRAM_Command & 0xffff) * 128;
		FlashStatus = 0x1111800400C20000;
		break;
	default:
		if (ShowDebugMessages)
			DisplayError("Writing %X to flash ram command register", FlashRAM_Command);
	}
}