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path: root/drivers/at45.c
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/* Driver for ATMEL DataFlash support
 * Author : Hamid Ikdoumi (Atmel)
 *
 * 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., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 *
 */

#include <config.h>
#include <common.h>

#ifdef CONFIG_HAS_DATAFLASH
#include <dataflash.h>


#define AT91C_TIMEOUT_WRDY			200000


/*----------------------------------------------------------------------*/
/* \fn    AT91F_DataFlashSendCommand					*/
/* \brief Generic function to send a command to the dataflash		*/
/*----------------------------------------------------------------------*/ 
AT91S_DataFlashStatus AT91F_DataFlashSendCommand(
	AT91PS_DataFlash pDataFlash,
	unsigned char OpCode,
	unsigned int CmdSize,
	unsigned int DataflashAddress)
{
	unsigned int adr;

	if ( (pDataFlash->pDataFlashDesc->state) != IDLE)
		return DATAFLASH_BUSY;

	/* process the address to obtain page address and byte address */
	adr = ((DataflashAddress / (pDataFlash->pDevice->pages_size)) << 
		pDataFlash->pDevice->page_offset) + (DataflashAddress % 
		(pDataFlash->pDevice->pages_size));

	/* fill the  command  buffer */
	pDataFlash->pDataFlashDesc->command[0] = OpCode;
	if (pDataFlash->pDevice->pages_number >= 16384) {
		pDataFlash->pDataFlashDesc->command[1] = 
			(unsigned char)((adr & 0x0F000000) >> 24);
		pDataFlash->pDataFlashDesc->command[2] = 
			(unsigned char)((adr & 0x00FF0000) >> 16);
		pDataFlash->pDataFlashDesc->command[3] = 
			(unsigned char)((adr & 0x0000FF00) >> 8);
		pDataFlash->pDataFlashDesc->command[4] = 
			(unsigned char)(adr & 0x000000FF);
	} else {
		pDataFlash->pDataFlashDesc->command[1] = 
			(unsigned char)((adr & 0x00FF0000) >> 16);
		pDataFlash->pDataFlashDesc->command[2] = 
			(unsigned char)((adr & 0x0000FF00) >> 8);
		pDataFlash->pDataFlashDesc->command[3] = 
			(unsigned char)(adr & 0x000000FF);
		pDataFlash->pDataFlashDesc->command[4] = 0;
	}
	pDataFlash->pDataFlashDesc->command[5] = 0;
	pDataFlash->pDataFlashDesc->command[6] = 0;
	pDataFlash->pDataFlashDesc->command[7] = 0;

	/* Initialize the SpiData structure for the spi write fuction */
	pDataFlash->pDataFlashDesc->tx_cmd_pt   =  
		pDataFlash->pDataFlashDesc->command;
	pDataFlash->pDataFlashDesc->tx_cmd_size =  CmdSize;
	pDataFlash->pDataFlashDesc->rx_cmd_pt   =  
		pDataFlash->pDataFlashDesc->command;
	pDataFlash->pDataFlashDesc->rx_cmd_size =  CmdSize;

	/* send the command and read the data */
	return AT91F_SpiWrite (pDataFlash->pDataFlashDesc); }


/*----------------------------------------------------------------------*/
/* \fn    AT91F_DataFlashGetStatus					*/
/* \brief Read the status register of the dataflash			*/
/*----------------------------------------------------------------------*/ 
AT91S_DataFlashStatus AT91F_DataFlashGetStatus(AT91PS_DataflashDesc pDesc) 
{
	AT91S_DataFlashStatus status;

	/* if a transfert is in progress ==> return 0 */
	if( (pDesc->state) != IDLE)
		return DATAFLASH_BUSY;

	/* first send the read status command (D7H) */
	pDesc->command[0] = DB_STATUS;
	pDesc->command[1] = 0;

	pDesc->DataFlash_state  = GET_STATUS;
	pDesc->tx_data_size 	= 0;	/* Transmit the command */
					/* and receive response */
	pDesc->tx_cmd_pt 		= pDesc->command;
	pDesc->rx_cmd_pt 		= pDesc->command;
	pDesc->rx_cmd_size 		= 2;
	pDesc->tx_cmd_size 		= 2;
	status = AT91F_SpiWrite (pDesc);

	pDesc->DataFlash_state = *( (unsigned char *) (pDesc->rx_cmd_pt) +1);

	return status;
}


/*----------------------------------------------------------------------*/
/* \fn    AT91F_DataFlashWaitReady					*/
/* \brief wait for dataflash ready (bit7 of the status register == 1)	*/
/*----------------------------------------------------------------------*/ 
AT91S_DataFlashStatus AT91F_DataFlashWaitReady(AT91PS_DataflashDesc 
pDataFlashDesc, unsigned int timeout) 
{
	pDataFlashDesc->DataFlash_state = IDLE;

	do {
		AT91F_DataFlashGetStatus(pDataFlashDesc);
		timeout--;
	} while( ((pDataFlashDesc->DataFlash_state & 0x80) != 0x80) && 
			(timeout > 0) );

	if((pDataFlashDesc->DataFlash_state & 0x80) != 0x80)
		return DATAFLASH_ERROR;

	return DATAFLASH_OK;
}


/*--------------------------------------------------------------------------*/
/* Function Name       : AT91F_DataFlashContinuousRead 			    */
/* Object              : Continuous stream Read 			    */
/* Input Parameters    : DataFlash Service				    */
/*						: <src> = dataflash address */
/*                     : <*dataBuffer> = data buffer pointer		    */
/*                     : <sizeToRead> = data buffer size		    */
/* Return value		: State of the dataflash			    */
/*--------------------------------------------------------------------------*/ 
AT91S_DataFlashStatus AT91F_DataFlashContinuousRead (
	AT91PS_DataFlash pDataFlash,
	int src,
	unsigned char *dataBuffer,
	int sizeToRead )
{
	AT91S_DataFlashStatus status;
	/* Test the size to read in the device */
	if ( (src + sizeToRead) > 
		(pDataFlash->pDevice->pages_size * 
		(pDataFlash->pDevice->pages_number)))
		return DATAFLASH_MEMORY_OVERFLOW;

	pDataFlash->pDataFlashDesc->rx_data_pt = dataBuffer;
	pDataFlash->pDataFlashDesc->rx_data_size = sizeToRead;
	pDataFlash->pDataFlashDesc->tx_data_pt = dataBuffer;
	pDataFlash->pDataFlashDesc->tx_data_size = sizeToRead;

	status = AT91F_DataFlashSendCommand 
			(pDataFlash, DB_CONTINUOUS_ARRAY_READ, 8, src);
	/* Send the command to the dataflash */
	return(status);
}


/*---------------------------------------------------------------------------*/
/* Function Name       : AT91F_DataFlashPagePgmBuf			     */
/* Object              : Main memory page program thru buffer 1 or buffer 2  */
/* Input Parameters    : DataFlash Service				     */
/*						: <*src> = Source buffer     */
/*                     : <dest> = dataflash destination address		     */
/*                     : <SizeToWrite> = data buffer size		     */
/* Return value		: State of the dataflash			     */
/*---------------------------------------------------------------------------*/ 
AT91S_DataFlashStatus AT91F_DataFlashPagePgmBuf(
	AT91PS_DataFlash pDataFlash,
	unsigned char *src,
	unsigned int dest,
	unsigned int SizeToWrite)
{
	int cmdsize;
	pDataFlash->pDataFlashDesc->tx_data_pt = src;
	pDataFlash->pDataFlashDesc->tx_data_size = SizeToWrite;
	pDataFlash->pDataFlashDesc->rx_data_pt = src;
	pDataFlash->pDataFlashDesc->rx_data_size = SizeToWrite;

	cmdsize = 4;
	/* Send the command to the dataflash */
	if (pDataFlash->pDevice->pages_number >= 16384)
		cmdsize = 5;
	return(AT91F_DataFlashSendCommand (pDataFlash, DB_PAGE_PGM_BUF1, 
cmdsize, dest)); }


/*---------------------------------------------------------------------------*/
/* Function Name       : AT91F_MainMemoryToBufferTransfert		     */
/* Object              : Read a page in the SRAM Buffer 1 or 2		     */
/* Input Parameters    : DataFlash Service				     */
/*                     : Page concerned					     */
/*                     : 						     */
/* Return value		: State of the dataflash			     */
/*---------------------------------------------------------------------------*/ 
AT91S_DataFlashStatus AT91F_MainMemoryToBufferTransfert(
	AT91PS_DataFlash pDataFlash,
	unsigned char BufferCommand,
	unsigned int page)
{
	int cmdsize;
	/* Test if the buffer command is legal */
	if ((BufferCommand != DB_PAGE_2_BUF1_TRF) 
		&& (BufferCommand != DB_PAGE_2_BUF2_TRF))
		return DATAFLASH_BAD_COMMAND;

	/* no data to transmit or receive */
	pDataFlash->pDataFlashDesc->tx_data_size = 0;
	cmdsize = 4;
	if (pDataFlash->pDevice->pages_number >= 16384)
		cmdsize = 5;
	return(AT91F_DataFlashSendCommand (pDataFlash, BufferCommand, cmdsize, 
page*pDataFlash->pDevice->pages_size));
}


/*-------------------------------------------------------------------------- */
/* Function Name       : AT91F_DataFlashWriteBuffer			     */
/* Object              : Write data to the internal sram buffer 1 or 2	     */
/* Input Parameters    : DataFlash Service				     */
/*			: <BufferCommand> = command to write buffer1 or 2    */
/*                     : <*dataBuffer> = data buffer to write		     */
/*                     : <bufferAddress> = address in the internal buffer    */
/*                     : <SizeToWrite> = data buffer size		     */
/* Return value		: State of the dataflash			     */
/*---------------------------------------------------------------------------*/
AT91S_DataFlashStatus AT91F_DataFlashWriteBuffer (
	AT91PS_DataFlash pDataFlash,
	unsigned char BufferCommand,
	unsigned char *dataBuffer,
	unsigned int bufferAddress,
	int SizeToWrite )
{
	int cmdsize;
	/* Test if the buffer command is legal */
	if ((BufferCommand != DB_BUF1_WRITE) 
		&& (BufferCommand != DB_BUF2_WRITE))
		return DATAFLASH_BAD_COMMAND;

	/* buffer address must be lower than page size */
	if (bufferAddress > pDataFlash->pDevice->pages_size)
		return DATAFLASH_BAD_ADDRESS;

	if ( (pDataFlash->pDataFlashDesc->state)  != IDLE)
		return DATAFLASH_BUSY;

	/* Send first Write Command */
	pDataFlash->pDataFlashDesc->command[0] = BufferCommand;
	pDataFlash->pDataFlashDesc->command[1] = 0;
	if (pDataFlash->pDevice->pages_number >= 16384) {
	    	pDataFlash->pDataFlashDesc->command[2] = 0;
	    	pDataFlash->pDataFlashDesc->command[3] = 
			(unsigned char)(((unsigned int)(bufferAddress &  
				pDataFlash->pDevice->byte_mask)) >> 8);
	    	pDataFlash->pDataFlashDesc->command[4] = 
			(unsigned char)((unsigned int)bufferAddress  & 0x00FF);
		cmdsize = 5;
	} else {
	    	pDataFlash->pDataFlashDesc->command[2] = 
			(unsigned char)(((unsigned int)(bufferAddress & 
				pDataFlash->pDevice->byte_mask)) >> 8);
	    	pDataFlash->pDataFlashDesc->command[3] = 
			(unsigned char)((unsigned int)bufferAddress  & 0x00FF);
	    	pDataFlash->pDataFlashDesc->command[4] = 0;
		cmdsize = 4;
	}

	pDataFlash->pDataFlashDesc->tx_cmd_pt 	 = 
		pDataFlash->pDataFlashDesc->command;
	pDataFlash->pDataFlashDesc->tx_cmd_size = cmdsize;
	pDataFlash->pDataFlashDesc->rx_cmd_pt 	 = 
		pDataFlash->pDataFlashDesc->command;
	pDataFlash->pDataFlashDesc->rx_cmd_size = cmdsize;

	pDataFlash->pDataFlashDesc->rx_data_pt 	= dataBuffer;
	pDataFlash->pDataFlashDesc->tx_data_pt 	= dataBuffer;
	pDataFlash->pDataFlashDesc->rx_data_size 	= SizeToWrite;
	pDataFlash->pDataFlashDesc->tx_data_size 	= SizeToWrite;

	return AT91F_SpiWrite(pDataFlash->pDataFlashDesc);
}

/*---------------------------------------------------------------------------*/
/* Function Name       : AT91F_PageErase                                     */
/* Object              : Erase a page 					     */
/* Input Parameters    : DataFlash Service				     */
/*                     : Page concerned					     */
/*                     : 						     */
/* Return value		: State of the dataflash			     */
/*---------------------------------------------------------------------------*/
AT91S_DataFlashStatus AT91F_PageErase(
	AT91PS_DataFlash pDataFlash,
	unsigned int page)
{
	int cmdsize;
	/* Test if the buffer command is legal */
	/* no data to transmit or receive */
    	pDataFlash->pDataFlashDesc->tx_data_size = 0;

	cmdsize = 4;
	if (pDataFlash->pDevice->pages_number >= 16384)
		cmdsize = 5;
	return(AT91F_DataFlashSendCommand (pDataFlash, DB_PAGE_ERASE, cmdsize, 
page*pDataFlash->pDevice->pages_size));
}


/*---------------------------------------------------------------------------*/
/* Function Name       : AT91F_BlockErase                                    */
/* Object              : Erase a Block 					     */
/* Input Parameters    : DataFlash Service				     */
/*                     : Page concerned					     */
/*                     : 						     */
/* Return value		: State of the dataflash			     */
/*---------------------------------------------------------------------------*/ 
AT91S_DataFlashStatus AT91F_BlockErase(
	AT91PS_DataFlash pDataFlash,
	unsigned int block)
{
	int cmdsize;
	/* Test if the buffer command is legal */
	/* no data to transmit or receive */
    	pDataFlash->pDataFlashDesc->tx_data_size = 0;
	cmdsize = 4;
	if (pDataFlash->pDevice->pages_number >= 16384)
		cmdsize = 5;
	return(AT91F_DataFlashSendCommand (pDataFlash, DB_BLOCK_ERASE,cmdsize, 
block*8*pDataFlash->pDevice->pages_size));
}

/*---------------------------------------------------------------------------*/
/* Function Name       : AT91F_WriteBufferToMain			     */
/* Object              : Write buffer to the main memory		     */
/* Input Parameters    : DataFlash Service				     */
/*		: <BufferCommand> = command to send to buffer1 or buffer2    */
/*                     : <dest> = main memory address			     */
/* Return value		: State of the dataflash			     */
/*---------------------------------------------------------------------------*/ 
AT91S_DataFlashStatus AT91F_WriteBufferToMain (
	AT91PS_DataFlash pDataFlash,
	unsigned char BufferCommand,
	unsigned int dest )
{
	int cmdsize;
	/* Test if the buffer command is correct */
	if ((BufferCommand != DB_BUF1_PAGE_PGM) &&
	    (BufferCommand != DB_BUF1_PAGE_ERASE_PGM) &&
	    (BufferCommand != DB_BUF2_PAGE_PGM) &&
	    (BufferCommand != DB_BUF2_PAGE_ERASE_PGM) )
		return DATAFLASH_BAD_COMMAND;

	/* no data to transmit or receive */
	pDataFlash->pDataFlashDesc->tx_data_size = 0;

	cmdsize = 4;
	if (pDataFlash->pDevice->pages_number >= 16384)
		cmdsize = 5;
	/* Send the command to the dataflash */
	return(AT91F_DataFlashSendCommand (pDataFlash, BufferCommand, cmdsize,
						dest)); }


/*---------------------------------------------------------------------------*/
/* Function Name       : AT91F_PartialPageWrite				     */
/* Object              : Erase partielly a page				     */
/* Input Parameters    : <page> = page number				     */
/*			: <AdrInpage> = adr to begin the fading		     */
/*                     : <length> = Number of bytes to erase		     */
/*---------------------------------------------------------------------------*/ 
AT91S_DataFlashStatus AT91F_PartialPageWrite (
	AT91PS_DataFlash pDataFlash,
	unsigned char *src,
	unsigned int dest,
	unsigned int size)
{
	unsigned int page;
	unsigned int AdrInPage;

	page = dest / (pDataFlash->pDevice->pages_size);
	AdrInPage = dest % (pDataFlash->pDevice->pages_size);

	/* Read the contents of the page in the Sram Buffer */
	AT91F_MainMemoryToBufferTransfert(pDataFlash, 
						DB_PAGE_2_BUF1_TRF, page);
	AT91F_DataFlashWaitReady(pDataFlash->pDataFlashDesc, 
						AT91C_TIMEOUT_WRDY);
	/*Update the SRAM buffer */
	AT91F_DataFlashWriteBuffer(pDataFlash, DB_BUF1_WRITE, src, 
					AdrInPage, size);

	AT91F_DataFlashWaitReady(pDataFlash->pDataFlashDesc, 
					AT91C_TIMEOUT_WRDY);

	/* Erase page if a 128 Mbits device */
	if (pDataFlash->pDevice->pages_number >= 16384) {
		AT91F_PageErase(pDataFlash, page);
		/* Rewrite the modified Sram Buffer in the main memory */
		AT91F_DataFlashWaitReady(pDataFlash->pDataFlashDesc, 
						AT91C_TIMEOUT_WRDY);
	}

	/* Rewrite the modified Sram Buffer in the main memory */
	return(AT91F_WriteBufferToMain(pDataFlash, DB_BUF1_PAGE_ERASE_PGM, 
				(page*pDataFlash->pDevice->pages_size)));
}

/*---------------------------------------------------------------------------*/
/* Function Name       : AT91F_DataFlashWrite				     */
/* Object              :						     */
/* Input Parameters    : <*src> = Source buffer				     */
/*                     : <dest> = dataflash adress			     */
/*                     : <size> = data buffer size			     */
/*---------------------------------------------------------------------------*/ 
AT91S_DataFlashStatus AT91F_DataFlashWrite(
	AT91PS_DataFlash pDataFlash,
	unsigned char *src,
	int dest,
	int size )
{
	unsigned int length;
	unsigned int page;
	unsigned int status;

	AT91F_SpiEnable(pDataFlash->pDevice->cs);

	if ( (dest + size) > (pDataFlash->pDevice->pages_size * 
					(pDataFlash->pDevice->pages_number)))
		return DATAFLASH_MEMORY_OVERFLOW;

	/* If destination does not fit a page start address */
	if ((dest % ((unsigned int)(pDataFlash->pDevice->pages_size)))  != 0 ) 
	{
		length = pDataFlash->pDevice->pages_size - 
				(dest % 
				((unsigned int)
				(pDataFlash->pDevice->pages_size)));

		if (size < length)
			length = size;

		if(!AT91F_PartialPageWrite(pDataFlash,src, dest, length))
			return DATAFLASH_ERROR;

		AT91F_DataFlashWaitReady(pDataFlash->pDataFlashDesc, 
			AT91C_TIMEOUT_WRDY);

		/* Update size, source and destination pointers */
		size -= length;
		dest += length;
		src += length;
	}

	while (( size - pDataFlash->pDevice->pages_size ) >= 0 ) {
		/* program dataflash page */
		page = (unsigned int)dest / (pDataFlash->pDevice->pages_size);

		status = AT91F_DataFlashWriteBuffer(pDataFlash, 
				DB_BUF1_WRITE, src, 0, 
				pDataFlash->pDevice->pages_size);
		AT91F_DataFlashWaitReady(pDataFlash->pDataFlashDesc, 
						AT91C_TIMEOUT_WRDY);

		status = AT91F_PageErase(pDataFlash, page);
		AT91F_DataFlashWaitReady(pDataFlash->pDataFlashDesc, 
						AT91C_TIMEOUT_WRDY);
		if (!status)
			return DATAFLASH_ERROR;

		status = AT91F_WriteBufferToMain (pDataFlash, 
						DB_BUF1_PAGE_PGM, dest);
		if(!status)
			return DATAFLASH_ERROR;

		AT91F_DataFlashWaitReady(pDataFlash->pDataFlashDesc, 
						AT91C_TIMEOUT_WRDY);

		/* Update size, source and destination pointers */
		size -= pDataFlash->pDevice->pages_size;
		dest += pDataFlash->pDevice->pages_size;
		src  += pDataFlash->pDevice->pages_size;
	}

	/* If still some bytes to read */
	if ( size > 0 ) {
		/* program dataflash page */
		if(!AT91F_PartialPageWrite(pDataFlash, src, dest, size) )
			return DATAFLASH_ERROR;

		AT91F_DataFlashWaitReady(pDataFlash->pDataFlashDesc, 
						AT91C_TIMEOUT_WRDY);
	}
	return DATAFLASH_OK;
}


/*---------------------------------------------------------------------------*/
/* Function Name       : AT91F_DataFlashRead 				     */
/* Object              : Read a block in dataflash			     */
/* Input Parameters    : 						     */
/* Return value		: 						     */
/*---------------------------------------------------------------------------*/
int AT91F_DataFlashRead(
	AT91PS_DataFlash pDataFlash,
	unsigned long addr,
	unsigned long size,
	char *buffer)
{
	unsigned long SizeToRead;

	AT91F_SpiEnable(pDataFlash->pDevice->cs);

	if(AT91F_DataFlashWaitReady(pDataFlash->pDataFlashDesc, 
					AT91C_TIMEOUT_WRDY) != DATAFLASH_OK)
		return -1;

	while (size) {
		SizeToRead = (size < 0x8000)? size:0x8000;

		if (AT91F_DataFlashWaitReady(pDataFlash->pDataFlashDesc, 
					AT91C_TIMEOUT_WRDY) != DATAFLASH_OK)
			return -1;

		if (AT91F_DataFlashContinuousRead (pDataFlash, addr, 
				(uchar *) buffer, SizeToRead) != DATAFLASH_OK)
			return -1;

		size -= SizeToRead;
		addr += SizeToRead;
		buffer += SizeToRead;
	}

	return DATAFLASH_OK;
}