fmd.c

WINce的ECC算法,和读写函数,可对比MTD NAND ECC来学习

    }

    NF_CE_H();

    //  Copmare with the ECC generated from the HW

    if(eccBuf[0] != eccRegVal.bECCBuf[0] ||
       	eccBuf[1] != eccRegVal.bECCBuf[1]  ||
       	eccBuf[2] != eccRegVal.bECCBuf[2] ) {

        Uart_Printf("FMD: ECC ERROR - Page #: %d\r\n", startSectorAddr);

        //  Now try to correct them
        if(!ECC_CorrectData(pSectorBuff, eccBuf, eccRegVal.bECCBuf))
        {
            Uart_Printf("FMD: Unable to correct the ECC error - Page #: %d\r\n", startSectorAddr);
						return FALSE;
        }
    }

    return TRUE;
}

//
//  IsBlockBad
//
//  Check to see if the given block is bad. A block is bad if the 517th byte on
//  the first or second page is not 0xff.
//
//  blockID:    The block address. We need to convert this to page address
//
//
BOOL IsBlockBad(BLOCK_ID blockID)
{
    DWORD   dwPageID = blockID << 5;
    BOOL    bRet = FALSE;
    BYTE    wFlag;

    //  Enable the chip
    NF_CE_L();

    //  Issue the command
    NF_CMD(CMD_READ2);

    //  Set up address
    NF_ADDR(VALIDADDR);
    NF_ADDR((dwPageID) & 0xff);
    NF_ADDR((dwPageID >> 8) & 0xff);

    NF_ADDR((dwPageID >> 16) & 0xff);

    //  Wait for Ready bit
    NF_WAITRB();

    //  Now get the byte we want
    wFlag = (BYTE) NF_DATA_R();

    if(wFlag != 0xff) {
        bRet = TRUE;
    }

    //  Disable the chip
    NF_CE_H();

    return bRet;
}

//
//  FMD_GetBlockStatus
//
//  Returns the status of a block.  The status information is stored in the spare area of the first sector for
//  the respective block.
//
//  A block is BAD if the bBadBlock byte on the first page is not equal to 0xff.
//
DWORD FMD_GetBlockStatus(BLOCK_ID blockID)
{
    SECTOR_ADDR sectorAddr = blockID << LOG_2_PAGES_PER_BLOCK;
    SectorInfo SI;
    DWORD dwResult = 0;

	if(!FMD_ReadSector(sectorAddr, NULL, &SI, 1))
	{
        return BLOCK_STATUS_UNKNOWN;
	}

    if(!(SI.bOEMReserved & OEM_BLOCK_READONLY))
	{
        dwResult |= BLOCK_STATUS_READONLY;
	}

    if(SI.bBadBlock != 0xFF)
	{
        dwResult |= BLOCK_STATUS_BAD;
	}

    return dwResult;
}



//  ************** FMD_EraseBlock ***********
//  Erase the given block,modified   by Scyclone

BOOL FMD_EraseBlock(BLOCK_ID blockID)
{
    BOOL    bRet = TRUE;
    DWORD   dwPageID = blockID << 5;
#ifdef Debug2410mon
		Uart_Printf("Erasing block %d \n", blockID);
#endif
		if(blockID < IMAGE_START_BLOCK)					//  Protect the NBL region
		{
			bRet = FALSE;
			return bRet;
		}
    //  Enable the chip
    NF_CE_L();

    //  Issue command
    NF_CMD(CMD_ERASE);

    //  Set up address
    NF_ADDR((dwPageID) & 0xff);

    NF_ADDR((dwPageID >> 8) & 0xff);

    NF_ADDR((dwPageID >> 16) & 0xff);

    //  Complete erase operation
    NF_CMD(CMD_ERASE2);

    //  Wait for ready bit
    NF_WAITRB();

    //  Check the status
    NF_CMD(CMD_STATUS);

    if (NF_DATA_R() & STATUS_ERROR){
        Uart_Printf("######## Error Erasing block %d!\n", blockID);
        bRet = FALSE;
    }

    NF_CE_H();

    return bRet;
}



//  FMD_WriteSector
//
//  Write dwNumPages pages to the startSectorAddr
//
BOOL FMD_WriteSector(SECTOR_ADDR startSectorAddr, LPBYTE pSectorBuff, PSectorInfo pSectorInfoBuff,DWORD dwNumSectors)
{
    DWORD   i;
    BOOL    bRet = TRUE;
    DWORD   dwECCVal;
    BYTE    eccBuf[4];

		//	RETAILMSG(1, (TEXT("FMD_WriteSector:startSectorAddr = %x, dwNumSectors = %x \r\n"), startSectorAddr, dwNumSectors));
    //  Sanity check
    //  BUGBUGBUG: I need to come back to support dwNumSectors > 1
    //
    if((!pSectorBuff && !pSectorInfoBuff) || dwNumSectors != 1)
    {
        Uart_Printf("Invalid parameters!\r\n");
        return FALSE;
    }
		NF_Reset();

    if(!pSectorBuff) {
				//        RETAILMSG(1, (TEXT("pSectorBuff = %x \r\n"), pSectorBuff));
        //  If we are asked just to write the SectorInfo, we will do that separately
        bRet = NAND_WriteSectorInfo(startSectorAddr, pSectorInfoBuff);
		return bRet;			// Do not write the actual sector information...
    }
		//Uart_Printf("write sector start \r\n");

    NF_RSTECC();					//  Initialize ECC register
    NF_CE_L();						//  Enable Chip
		NF_CMD(CMD_READ);			//  Issue command
    NF_CMD(CMD_WRITE);
    NF_ADDR(0x00);				//  Setup address
    NF_ADDR((startSectorAddr) & 0xff);
    NF_ADDR((startSectorAddr >> 8) & 0xff);

		NF_ADDR((startSectorAddr >> 16) & 0xff);

    //  Special case to handle un-aligned buffer pointer.
    //
    /*   暂时屏蔽
    if( ((DWORD) pSectorBuff) & 0x3)
    {
        //  Write the data
        for(i=0; i<SECTOR_SIZE; i++)
            NF_DATA_W(pSectorBuff[i]);
    }
    else {
        WritePage512(pSectorBuff, pNFDATA);
    }
    */
		for(i=0; i<SECTOR_SIZE; i++)
            NF_DATA_W(pSectorBuff[i]);

    //  Read out the ECC value generated by HW
    dwECCVal = NF_ECC();

		// Write the SectorInfo data to the media
		// NOTE: This hardware is odd: only a byte can be written at a time and it must reside in the
		//       upper byte of a USHORT.
		if(pSectorInfoBuff)
		{
        //  Write the first reserved field (DWORD)
        NF_DATA_W( (pSectorInfoBuff->dwReserved1 >> 24) & 0xff );
        NF_DATA_W( (pSectorInfoBuff->dwReserved1 >> 16) & 0xff );
        NF_DATA_W( (pSectorInfoBuff->dwReserved1 >> 8 ) & 0xff );
        NF_DATA_W( (pSectorInfoBuff->dwReserved1) & 0xff );

        //  Write OEM reserved flag
        NF_DATA_W( (pSectorInfoBuff->bOEMReserved) );

        //  Write the bad block flag
        NF_DATA_W( (pSectorInfoBuff->bBadBlock) );

        //  Write the second reserved field
        NF_DATA_W( (pSectorInfoBuff->wReserved2 >> 8) & 0xff );
        NF_DATA_W( (pSectorInfoBuff->wReserved2) & 0xff );

		}else
		{
				// Make sure we advance the Flash's write pointer (even though we aren't writing the SectorInfo data)
				for(i=0; i<sizeof(SectorInfo); i++)
            NF_DATA_W(0xff);
		}

    //  ECC stuff should be here
    eccBuf[0] = (BYTE) ((dwECCVal) & 0xff);
    eccBuf[1] = (BYTE) ((dwECCVal >> 8) & 0xff);
    eccBuf[2] = (BYTE) ((dwECCVal >> 16) & 0xff);

    //  Write the ECC value to the flash
    for(i=0; i<3; i++) {
        NF_DATA_W(eccBuf[i]);
    }

    //  Finish up the write operation
    NF_CMD(CMD_WRITE2);

    //  Wait for RB
    NF_WAITRB();

    //  Check the status
    NF_CMD(CMD_STATUS);

    if(NF_DATA_R() & STATUS_ERROR) {
        Uart_Printf("FMD_WriteSector() ######## Error Programming page %d!\r\n", startSectorAddr);
        bRet = FALSE;
    }

    //  Disable the chip
    NF_CE_H();
    return bRet;
}

/*
 *  MarkBlockBad
 *
 *  Mark the block as a bad block. We need to write a 00 to the 517th byte
 */

BOOL MarkBlockBad(BLOCK_ID blockID)
{
    DWORD   dwStartPage = blockID << 5;
    BOOL    bRet = TRUE;

    //  Enable chip
    NF_CE_L();

    //  Issue command
    //  We are dealing with spare area
    NF_CMD(CMD_READ2);
    NF_CMD(CMD_WRITE);

    //  Set up address
    NF_ADDR(VALIDADDR);
    NF_ADDR((dwStartPage) & 0xff);
    NF_ADDR((dwStartPage >> 8) & 0xff);
		NF_ADDR((dwStartPage >> 16) & 0xff);

    NF_DATA_W(BADBLOCKMARK);

    //  Copmlete the write
    NF_CMD(CMD_WRITE2);

    //  Wait for RB
    NF_WAITRB();

    //  Get the status
    NF_CMD(CMD_STATUS);

    if(NF_DATA_R() &  STATUS_ERROR) {
        Uart_Printf("######## Failed to mark the block bad!\n");
        bRet = FALSE;
    }

    //  Disable chip select
    NF_CE_H();

    return bRet;
}

//
//  FMD_SetBlockStatus
//
//  Sets the status of a block.  Only implement for bad blocks for now.
//  Returns TRUE if no errors in setting.
//
BOOL FMD_SetBlockStatus(BLOCK_ID blockID, DWORD dwStatus)
{
    SECTOR_ADDR sectorAddr = blockID << LOG_2_PAGES_PER_BLOCK;
	BYTE bStatus = 0;

    if(dwStatus & BLOCK_STATUS_BAD)
	{
        if(!MarkBlockBad (blockID))
        {
            return FALSE;
        }
    }

    // We don't currently support setting a block to read-only, so fail if request is
    // for read-only and block is not currently read-only.
    if(dwStatus & BLOCK_STATUS_READONLY)
	{
        if(!(FMD_GetBlockStatus(blockID) & BLOCK_STATUS_READONLY))
        {
            return FALSE;
        }
    }

    return TRUE;
}



//------------------------------- Private Interface (NOT used by the FAL) --------------------------

//  FMD_GetOEMReservedByte
//
//  Retrieves the OEM reserved byte (for metadata) for the specified physical sector.
//
//
BOOL FMD_GetOEMReservedByte(SECTOR_ADDR physicalSectorAddr, PBYTE pOEMReserved)
{
    //  Enable chip select
    NF_CE_L();

    //  Issue command
    NF_CMD(CMD_READ2);

    //  Set up address
    NF_ADDR(OEMADDR);
    NF_ADDR((physicalSectorAddr) & 0xff);
    NF_ADDR((physicalSectorAddr >> 8) & 0xff);

    NF_ADDR((physicalSectorAddr >> 16) & 0xff);

    //  Wait for the ready bit
    NF_WAITRB();

    //  Read the data
    *pOEMReserved = (BYTE) NF_DATA_R();

    //  Disable chip select
    NF_CE_H();

	return TRUE;

}


//  FMD_SetOEMReservedByte
//
//  Sets the OEM reserved byte (for metadata) for the specified physical sector.
//
BOOL FMD_SetOEMReservedByte(SECTOR_ADDR physicalSectorAddr, BYTE bOEMReserved)
{
    BOOL    bRet = TRUE;

    //  Enable chip select
    NF_CE_L();

    //  Issue command
    NF_CMD(CMD_READ2);
    NF_CMD(CMD_WRITE);

    //  Set up address
    NF_ADDR(OEMADDR);
    NF_ADDR((physicalSectorAddr) & 0xff);
    NF_ADDR((physicalSectorAddr >> 8) & 0xff);

    NF_ADDR((physicalSectorAddr >> 16) & 0xff);

    //  Write the data
    NF_DATA_W(bOEMReserved);

    //  Complete the write
    NF_CMD(CMD_WRITE2);

    //  Wait for the ready bit
    NF_WAITRB();

    //  Read the status
    NF_CMD(CMD_STATUS);

    //  Check the status
    if(NF_DATA_R() & STATUS_ERROR) {
        Uart_Printf("######## Failed to set OEM Reserved byte!\n");
        bRet = FALSE;
    }

    //  Disable chip select
    NF_CE_H();

    return bRet;
}

//---------------------------------------- Helper Functions ----------------------------------------

//  Interface function for testing purpose.
//
BOOL FMD_ReadSpare(DWORD dwStartPage, LPBYTE pBuff, DWORD dwNumPages)
{
    DWORD   i, n;

    //  Enable chip select
    NF_CE_L();

    //  Issue command
    NF_CMD(CMD_READ2);

    //  Set up address
    NF_ADDR(0x00);
    NF_ADDR((dwStartPage) & 0xff);
    NF_ADDR((dwStartPage >> 8) & 0xff);

		NF_ADDR((dwStartPage >> 16) & 0xff);

    //  Wait for Ready bit
    NF_WAITRB();

    //  Now read out the data
    for(n=0; n<dwNumPages; n++) {
        //  Read the spare area
        for(i=0; i<16; i++) {
            pBuff[n*16+i] = (BYTE) NF_DATA_R();
        }

        NF_WAITRB();
    }

    NF_CE_H();

    return TRUE;
}