#include "stmflash.h"

//////////////////////////////////////////////////////////////////////////////////
//本程序只供学习使用，未经作者许可，不得用于其它任何用途
//ALIENTEK战舰STM32开发板
//STM32 FLASH 驱动代码
//正点原子@ALIENTEK
//技术论坛:www.openedv.com
//修改日期:2012/9/13
//版本：V1.0
//版权所有，盗版必究。
//Copyright(C) 广州市星翼电子科技有限公司 2009-2019
//All rights reserved
//////////////////////////////////////////////////////////////////////////////////

//读取指定地址的半字(16位数据)
//faddr:读地址(此地址必须为2的倍数!!)
//返回值:对应数据.
u16 STMFLASH_ReadHalfWord ( u32 faddr )
{
    return * ( vu16* ) faddr;
}
#if STM32_FLASH_WREN	//如果使能了写   
//不检查的写入
//WriteAddr:起始地址
//pBuffer:数据指针
//NumToWrite:半字(16位)数
void STMFLASH_Write_NoCheck ( u32 WriteAddr, u16 *pBuffer, u16 NumToWrite )
{
    u16 i;

    for ( i = 0; i < NumToWrite; i++ )
    {
        FLASH_ProgramHalfWord ( WriteAddr, pBuffer[i] );
        WriteAddr += 2; //地址增加2.
    }
}
//从指定地址开始写入指定长度的数据
//WriteAddr:起始地址(此地址必须为2的倍数!!)
//pBuffer:数据指针
//NumToWrite:半字(16位)数(就是要写入的16位数据的个数.)
#if STM32_FLASH_SIZE<256
#define STM_SECTOR_SIZE 1024 //字节
#else
#define STM_SECTOR_SIZE	2048
#endif
u16 STMFLASH_BUF[STM_SECTOR_SIZE / 2]; //最多是2K字节

extern uint32_t flash_flag;

void STMFLASH_Write ( u32 WriteAddr, u16 *pBuffer, u16 NumToWrite )
{
    u32 secpos;	   //扇区地址
    u16 secoff;	   //扇区内偏移地址(16位字计算)
    u16 secremain; //扇区内剩余地址(16位字计算)
    u16 i;
    u32 offaddr;   //去掉0X08000000后的地址

    FLASH_Unlock();						//解锁
    offaddr = WriteAddr - STM32_FLASH_BASE;		//实际偏移地址.
    secpos = offaddr / STM_SECTOR_SIZE;			//扇区地址  0~127 for STM32F103RBT6
    secoff = ( offaddr % STM_SECTOR_SIZE ) / 2;		//在扇区内的偏移(2个字节为基本单位.)
    secremain = STM_SECTOR_SIZE / 2 - secoff;		//扇区剩余空间大小

    if ( NumToWrite <= secremain ) secremain = NumToWrite; //不大于该扇区范围

    while ( 1 )
    {
        STMFLASH_Read ( secpos * STM_SECTOR_SIZE + STM32_FLASH_BASE, STMFLASH_BUF, STM_SECTOR_SIZE / 2 ); //读出整个扇区的内容

        for ( i = 0; i < secremain; i++ ) //校验数据
        {
            if ( STMFLASH_BUF[secoff + i] != 0XFFFF ) break; //需要擦除
        }

        if ( i < secremain ) //需要擦除
        {
            FLASH_ErasePage ( secpos * STM_SECTOR_SIZE + STM32_FLASH_BASE ); //擦除这个扇区

            for ( i = 0; i < secremain; i++ ) //复制
            {
                STMFLASH_BUF[i + secoff] = pBuffer[i];
            }

            STMFLASH_Write_NoCheck ( secpos * STM_SECTOR_SIZE + STM32_FLASH_BASE, STMFLASH_BUF, STM_SECTOR_SIZE / 2 ); //写入整个扇区
        }
        else STMFLASH_Write_NoCheck ( WriteAddr, pBuffer, secremain ); //写已经擦除了的,直接写入扇区剩余区间.

        if ( NumToWrite == secremain ) break; //写入结束了
        else//写入未结束
        {
            secpos++;				//扇区地址增1
            secoff = 0;				//偏移位置为0
            pBuffer += secremain;  	//指针偏移
            WriteAddr += secremain;	//写地址偏移
            NumToWrite -= secremain;	//字节(16位)数递减

            if ( NumToWrite > ( STM_SECTOR_SIZE / 2 ) ) secremain = STM_SECTOR_SIZE / 2; //下一个扇区还是写不完
            else secremain = NumToWrite; //下一个扇区可以写完了
        }
    };

    FLASH_Lock();//上锁
}
#endif

//从指定地址开始读出指定长度的数据
//ReadAddr:起始地址
//pBuffer:数据指针
//NumToWrite:半字(16位)数
void STMFLASH_Read ( u32 ReadAddr, u16 *pBuffer, u16 NumToRead )
{
    uint32_t addr = 0x08016000 + 400 * 1024;
    u16 i;

    if ( ReadAddr >= addr )
    {
        for ( i = 0; i < NumToRead; i++ )
        {
            pBuffer[i] = 0x0000;
        }

        return;
    }

    for ( i = 0; i < NumToRead; i++ )
    {
        pBuffer[i] = STMFLASH_ReadHalfWord ( ReadAddr ); //读取2个字节.
        ReadAddr += 2; //偏移2个字节.
    }
}

//////////////////////////////////////////////////////////////////////////////////////////////////////
//WriteAddr:起始地址
//WriteData:要写入的数据
void Test_Write ( u32 WriteAddr, u16 WriteData )
{
    STMFLASH_Write ( WriteAddr, &WriteData, 1 ); //写入一个字
}