flash_data.c

此压缩包为杰得开发得z228的BSP的源代码,可以实现很多功能,尤其是视频解码有很好的效果.

/***************************************************************************
*   File:    flash_data.c  -   Implement the read and write functions
* 
*   The content of this file or document is CONFIDENTIAL and PROPRIETARY
*   to Jade Technologies Co., Ltd.  It is subject to the terms of a
*   License Agreement between Licensee and Jade Technologies Co., Ltd.
*   restricting among other things, the use, reproduction, distribution
*   and transfer.  Each of the embodiments, including this information 
*   and any derivative work shall retain this copyright notice.
* 
*   Copyright (c) 2005 Jade Technologies Co., Ltd. 
*   All rights reserved.
****************************************************************************/
#include "flash.h"

//------------------------------------------------------------------------------
// Macros
//------------------------------------------------------------------------------
#define MIN(__x,__y) ((__x)<(__y)?(__x):(__y)) 
#define MAX(__x,__y) ((__x)>(__y)?(__x):(__y)) 

unsigned char * CacheBuf;

unsigned long dwBlockAddr = 0;
unsigned long dwBlockStartAddr = 0;


//------------------------------------------------------------------------------
// Functions
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
//
// Checks the status of the flash device by checking toggle in bit 6.
//
// address - Address to check
//
// return 0 - Success -1 - Failure
//
//------------------------------------------------------------------------------
int FLA_cfi_check_status (unsigned long address)
{

	unsigned long dwTimeOut = 0;
	unsigned char status,Pre_status;
	
       Pre_status = FLASH(address) & 0x40;
	   
	// Get the current status	
	while(dwTimeOut < 0x7ffff)	{		
		status = FLASH(address) & 0x40;
		if(status == Pre_status)
			break;
		Pre_status = status;
		dwTimeOut ++;
	}
	
	// Return status
	if (dwTimeOut >= 0x7ffff)
		return -1;
	else
		return 0;
}

//------------------------------------------------------------------------------
//
// Writes a byte the flash device.
//   
// address - Address to write
// byte - Data to write
//
// return 0 - Success -1 - Failure
//
//------------------------------------------------------------------------------
int FLA_cfi_write_byte (unsigned long address, unsigned char byte)
{

	FLASH_COMMAND(0x5555, 0xaa);
        FLASH_COMMAND(0x2aaa, 0x55);
	FLASH_COMMAND(0x5555, 0xa0);
	FLASH(address) = byte;

	return FLA_cfi_check_status (address);
}

//------------------------------------------------------------------------------
//
// Reads a byte from the flash device.
//
// address - Address to read
// byte - Pointer to data to read
//
// return 0 - Success -1 - Failure
//
//------------------------------------------------------------------------------
int FLA_cfi_read_byte (unsigned long address, unsigned char * pbyte)
{
       *pbyte = FLASH(address);
       return FLA_cfi_check_status (address); 
}

//------------------------------------------------------------------------------
//
// Erases a block.
//
// address - Address to erase
//
// return 0 - Success -1 - Failure
//
//------------------------------------------------------------------------------
int FLA_cfi_erase_block (unsigned long address)
{
        //RETAILMSG(MSG_DATA, (_T("FLASH: FLA_cfi_erase_block: 0x%x\r\n"), address));
        	
	FLASH_COMMAND(0x5555, 0xaa);
	FLASH_COMMAND(0x2aaa, 0x55);
	FLASH_COMMAND(0x5555, 0x80);
	FLASH_COMMAND(0x5555, 0xaa);
	FLASH_COMMAND(0x2aaa, 0x55);
	
	FLASH_DATA(address, 0x30);
	
	return FLA_cfi_check_status (address);
}


//------------------------------------------------------------------------------
//
// Erases the entire chip.
//
// address - Address to erase
//
// return 0 - Success -1 - Failure
//
//------------------------------------------------------------------------------
void  FLA_cfi_erase_chip ( )
{
	RETAILMSG(MSG_DATA, (_T("FLASH: FLA_cfi_erase_chip\r\n")));
	
	FLASH_COMMAND(0x5555, 0xaa);
	FLASH_COMMAND(0x2aaa, 0x55);
	FLASH_COMMAND(0x5555, 0x80);
	FLASH_COMMAND(0x5555, 0xaa);
	FLASH_COMMAND(0x2aaa, 0x55);
	
	FLASH_COMMAND(0x5555, 0x10);
}