/******************** (C) COPYRIGHT 2008 STMicroelectronics ********************
* File Name          : stm32f10x_flash.c
* Author             : MCD Application Team
* Version            : V2.0
* Date               : 05/23/2008
* Description        : This file provides all the FLASH firmware functions.
********************************************************************************
* THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
* WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE TIME.
* AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY DIRECT,
* INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING FROM THE
* CONTENT OF SUCH SOFTWARE AND/OR THE USE MADE BY CUSTOMERS OF THE CODING
* INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
* FOR MORE INFORMATION PLEASE CAREFULLY READ THE LICENSE AGREEMENT FILE LOCATED 
* IN THE ROOT DIRECTORY OF THIS FIRMWARE PACKAGE.
*******************************************************************************/

/* Includes ------------------------------------------------------------------*/
#include "stm32f10x_flash.h"

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Flash Access Control Register bits */
#define ACR_LATENCY_Mask         ((u32)0x00000038)
#define ACR_HLFCYA_Mask          ((u32)0xFFFFFFF7)
#define ACR_PRFTBE_Mask          ((u32)0xFFFFFFEF)

#ifdef _FLASH_PROG
/* Flash Access Control Register bits */
#define ACR_PRFTBS_Mask          ((u32)0x00000020) 

/* Flash Control Register bits */
#define CR_PG_Set                ((u32)0x00000001)
#define CR_PG_Reset              ((u32)0x00001FFE) 

#define CR_PER_Set               ((u32)0x00000002)
#define CR_PER_Reset             ((u32)0x00001FFD)

#define CR_MER_Set               ((u32)0x00000004)
#define CR_MER_Reset             ((u32)0x00001FFB)

#define CR_OPTPG_Set             ((u32)0x00000010)
#define CR_OPTPG_Reset           ((u32)0x00001FEF)

#define CR_OPTER_Set             ((u32)0x00000020)
#define CR_OPTER_Reset           ((u32)0x00001FDF)

#define CR_STRT_Set              ((u32)0x00000040)
							 
#define CR_LOCK_Set              ((u32)0x00000080)

/* FLASH Mask */
#define RDPRT_Mask               ((u32)0x00000002)
#define WRP0_Mask                ((u32)0x000000FF)
#define WRP1_Mask                ((u32)0x0000FF00)
#define WRP2_Mask                ((u32)0x00FF0000)
#define WRP3_Mask                ((u32)0xFF000000)

/* FLASH Keys */
#define RDP_Key                  ((u16)0x00A5)
#define FLASH_KEY1               ((u32)0x45670123)
#define FLASH_KEY2               ((u32)0xCDEF89AB)

/* Delay definition */   
#define EraseTimeout             ((u32)0x00000FFF)
#define ProgramTimeout           ((u32)0x0000000F)
#endif

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
#ifdef _FLASH_PROG
static void delay(void);
#endif

/* Private functions ---------------------------------------------------------*/
/*******************************************************************************
* Function Name  : FLASH_SetLatency
* Description    : Sets the code latency value.
* Input          : - FLASH_Latency: specifies the FLASH Latency value.
*                    This parameter can be one of the following values:
*                       - FLASH_Latency_0: FLASH Zero Latency cycle
*                       - FLASH_Latency_1: FLASH One Latency cycle
*                       - FLASH_Latency_2: FLASH Two Latency cycles
* Output         : None
* Return         : None
*******************************************************************************/
void FLASH_SetLatency(u32 FLASH_Latency)
{
  /* Check the parameters */
  assert_param(IS_FLASH_LATENCY(FLASH_Latency));
  
  /* Sets the Latency value */
  FLASH->ACR &= ACR_LATENCY_Mask;
  FLASH->ACR |= FLASH_Latency;
}

/*******************************************************************************
* Function Name  : FLASH_HalfCycleAccessCmd
* Description    : Enables or disables the Half cycle flash access.
* Input          : - FLASH_HalfCycle: specifies the FLASH Half cycle Access mode.
*                    This parameter can be one of the following values:
*                       - FLASH_HalfCycleAccess_Enable: FLASH Half Cycle Enable
*                       - FLASH_HalfCycleAccess_Disable: FLASH Half Cycle Disable
* Output         : None
* Return         : None
*******************************************************************************/
void FLASH_HalfCycleAccessCmd(u32 FLASH_HalfCycleAccess)
{
  /* Check the parameters */
  assert_param(IS_FLASH_HALFCYCLEACCESS_STATE(FLASH_HalfCycleAccess));
  
  /* Enable or disable the Half cycle access */
  FLASH->ACR &= ACR_HLFCYA_Mask;
  FLASH->ACR |= FLASH_HalfCycleAccess;
}

/*******************************************************************************
* Function Name  : FLASH_PrefetchBufferCmd
* Description    : Enables or disables the Prefetch Buffer.
* Input          : - FLASH_PrefetchBuffer: specifies the Prefetch buffer status.
*                    This parameter can be one of the following values:
*                       - FLASH_PrefetchBuffer_Enable: FLASH Prefetch Buffer Enable
*                       - FLASH_PrefetchBuffer_Disable: FLASH Prefetch Buffer Disable
* Output         : None
* Return         : None
*******************************************************************************/
void FLASH_PrefetchBufferCmd(u32 FLASH_PrefetchBuffer)
{
  /* Check the parameters */
  assert_param(IS_FLASH_PREFETCHBUFFER_STATE(FLASH_PrefetchBuffer));
  
  /* Enable or disable the Prefetch Buffer */
  FLASH->ACR &= ACR_PRFTBE_Mask;
  FLASH->ACR |= FLASH_PrefetchBuffer;
}

#ifdef _FLASH_PROG
/*******************************************************************************
* Function Name  : FLASH_Unlock
* Description    : Unlocks the FLASH Program Erase Controller.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void FLASH_Unlock(void)
{
  /* Authorize the FPEC Access */
  FLASH->KEYR = FLASH_KEY1;
  FLASH->KEYR = FLASH_KEY2;
}

/*******************************************************************************
* Function Name  : FLASH_Lock
* Description    : Locks the FLASH Program Erase Controller.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void FLASH_Lock(void)
{
  /* Set the Lock Bit to lock the FPEC and the FCR */
  FLASH->CR |= CR_LOCK_Set;
}

/*******************************************************************************
* Function Name  : FLASH_ErasePage
* Description    : Erases a specified FLASH page.
* Input          : - Page_Address: The page address to be erased.
* Output         : None
* Return         : FLASH Status: The returned value can be: FLASH_BUSY, 
*                  FLASH_ERROR_PG, FLASH_ERROR_WRP, FLASH_COMPLETE or 
*                  FLASH_TIMEOUT.
*******************************************************************************/
FLASH_Status FLASH_ErasePage(u32 Page_Address)
{
  FLASH_Status status = FLASH_COMPLETE;

  /* Check the parameters */
  assert_param(IS_FLASH_ADDRESS(Page_Address));

  /* Wait for last operation to be completed */
  status = FLASH_WaitForLastOperation(EraseTimeout);
  
  if(status == FLASH_COMPLETE)
  { 
    /* if the previous operation is completed, proceed to erase the page */
    FLASH->CR|= CR_PER_Set;
    FLASH->AR = Page_Address; 
    FLASH->CR|= CR_STRT_Set;
    
    /* Wait for last operation to be completed */
    status = FLASH_WaitForLastOperation(EraseTimeout);

    if(status != FLASH_BUSY)
    {
      /* if the erase operation is completed, disable the PER Bit */
      FLASH->CR &= CR_PER_Reset;
    }
  }
  /* Return the Erase Status */
  return status;
}

/*******************************************************************************
* Function Name  : FLASH_EraseAllPages
* Description    : Erases all FLASH pages.
* Input          : None
* Output         : None
* Return         : FLASH Status: The returned value can be: FLASH_BUSY, 
*                  FLASH_ERROR_PG, FLASH_ERROR_WRP, FLASH_COMPLETE or 
*                  FLASH_TIMEOUT.
*******************************************************************************/
FLASH_Status FLASH_EraseAllPages(void)
{
  FLASH_Status status = FLASH_COMPLETE;

  /* Wait for last operation to be completed */
  status = FLASH_WaitForLastOperation(EraseTimeout);
  
  if(status == FLASH_COMPLETE)
  {
    /* if the previous operation is completed, proceed to erase all pages */
     FLASH->CR |= CR_MER_Set;
     FLASH->CR |= CR_STRT_Set;
    
    /* Wait for last operation to be completed */
    status = FLASH_WaitForLastOperation(EraseTimeout);

    if(status != FLASH_BUSY)
    {
      /* if the erase operation is completed, disable the MER Bit */
      FLASH->CR &= CR_MER_Reset;
    }
  }	   
  /* Return the Erase Status */
  return status;
}

/*******************************************************************************
* Function Name  : FLASH_EraseOptionBytes
* Description    : Erases the FLASH option bytes.
* Input          : None
* Output         : None
* Return         : FLASH Status: The returned value can be: FLASH_BUSY, 
*                  FLASH_ERROR_PG, FLASH_ERROR_WRP, FLASH_COMPLETE or 
*                  FLASH_TIMEOUT.
*******************************************************************************/
FLASH_Status FLASH_EraseOptionBytes(void)
{
  FLASH_Status status = FLASH_COMPLETE;
  
  /* Wait for last operation to be completed */
  status = FLASH_WaitForLastOperation(EraseTimeout);

  if(status == FLASH_COMPLETE)
  {
    /* Authorize the small information block programming */
    FLASH->OPTKEYR = FLASH_KEY1;
    FLASH->OPTKEYR = FLASH_KEY2;
    
    /* if the previous operation is completed, proceed to erase the option bytes */
    FLASH->CR |= CR_OPTER_Set;
    FLASH->CR |= CR_STRT_Set;

    /* Wait for last operation to be completed */
    status = FLASH_WaitForLastOperation(EraseTimeout);
    
    if(status == FLASH_COMPLETE)
    {
      /* if the erase operation is completed, disable the OPTER Bit */
      FLASH->CR &= CR_OPTER_Reset;
       
      /* Enable the Option Bytes Programming operation */
      FLASH->CR |= CR_OPTPG_Set;

      /* Enable the readout access */
      OB->RDP= RDP_Key; 

      /* Wait for last operation to be completed */
      status = FLASH_WaitForLastOperation(ProgramTimeout);
 
      if(status != FLASH_BUSY)
      {
        /* if the program operation is completed, disable the OPTPG Bit */
        FLASH->CR &= CR_OPTPG_Reset;
      }
    }
    else
    {
      if (status != FLASH_BUSY)
      {
        /* Disable the OPTPG Bit */
        FLASH->CR &= CR_OPTPG_Reset;
      }
    }  
  }
  /* Return the erase status */
  return status;
}

/*******************************************************************************
* Function Name  : FLASH_ProgramWord
* Description    : Programs a word at a specified address.
* Input          : - Address: specifies the address to be programmed.