AMiRo-OS

/************************************************************************************//**

* \file         Source\ARMCM4_STM32\cpu.c

* \brief        Bootloader cpu module source file.

* \ingroup      Target_ARMCM4_STM32

* \internal

*----------------------------------------------------------------------------------------

*                          C O P Y R I G H T

*----------------------------------------------------------------------------------------

*   Copyright (c) 2013  by Feaser    http://www.feaser.com    All rights reserved

*

*----------------------------------------------------------------------------------------

*                            L I C E N S E

*----------------------------------------------------------------------------------------

* This file is part of OpenBLT. OpenBLT 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 3 of the License, or (at your option) any later

* version.

*

* OpenBLT 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 OpenBLT.

* If not, see <http://www.gnu.org/licenses/>.

*

* A special exception to the GPL is included to allow you to distribute a combined work 

* that includes OpenBLT without being obliged to provide the source code for any 

* proprietary components. The exception text is included at the bottom of the license

* file <license.html>.

* 

* \endinternal

****************************************************************************************/

/****************************************************************************************

* Include files

****************************************************************************************/

#include "boot.h"                                /* bootloader generic header          */

/****************************************************************************************

* Macro definitions

****************************************************************************************/

/** \brief Pointer to the user program's reset vector. */

#define CPU_USER_PROGRAM_STARTADDR_PTR    ((blt_addr)(FlashGetUserProgBaseAddress() + 0x00000004))

/** \brief Pointer to the user program's vector table. */

#define CPU_USER_PROGRAM_VECTABLE_OFFSET  ((blt_int32u)FlashGetUserProgBaseAddress())

/****************************************************************************************

* Register definitions

****************************************************************************************/

/** \brief Vector table offset register. */

#define SCB_VTOR    (*((volatile blt_int32u *) 0xE000ED08))

/****************************************************************************************

* Hook functions

****************************************************************************************/

#if (BOOT_CPU_USER_PROGRAM_START_HOOK > 0)

extern blt_bool CpuUserProgramStartHook(void);

#endif

/****************************************************************************************

* External functions

****************************************************************************************/

extern void reset_handler(void);                      /* implemented in cstart.s       */

/************************************************************************************//**

** \brief     Starts the user program, if one is present. In this case this function

**            does not return. 

** \return    none.

**

****************************************************************************************/

void CpuStartUserProgram(void)

{

  void (*pProgResetHandler)(void);

  blt_addr msp;

  /* check if a user program is present by verifying the checksum */

  if (NvmVerifyChecksum() == BLT_FALSE)

  {

    /* not a valid user program so it cannot be started */

    return;

  }

  #if (BOOT_CPU_USER_PROGRAM_START_HOOK > 0)

  /* invoke callback */

  if (CpuUserProgramStartHook() == BLT_FALSE)

  {

    /* callback requests the user program to not be started */

    return;

  }

  #endif

  #if (BOOT_COM_ENABLE > 0)

  /* release the communication interface */

  ComFree();

  #endif

  /* reset the timer */

  TimerReset();

  /* remap user program's vector table */

  SCB_VTOR = CPU_USER_PROGRAM_VECTABLE_OFFSET & (blt_int32u)0x1FFFFF80;

  /* set the mainstack to vector table for user program start.

   */

  msp = *((blt_addr*)CPU_USER_PROGRAM_VECTABLE_OFFSET);

  asm volatile ("MSR MSP, %0" : : "r" (msp) );

  /* set the address where the bootloader needs to jump to. this is the address of

   * the 2nd entry in the user program's vector table. this address points to the

   * user program's reset handler.

   */

  pProgResetHandler = (void(*)(void))(*((blt_addr*)CPU_USER_PROGRAM_STARTADDR_PTR));

  /* start the user program by activating its reset interrupt service routine */

  pProgResetHandler();

} /*** end of CpuStartUserProgram ***/

/************************************************************************************//**

** \brief     Copies data from the source to the destination address.

** \param     dest Destination address for the data.

** \param     src  Source address of the data.

** \param     len  length of the data in bytes. 

** \return    none.

**

****************************************************************************************/

void CpuMemCopy(blt_addr dest, blt_addr src, blt_int16u len)

{

  blt_int8u *from, *to;

  /* set casted pointers */

  from = (blt_int8u *)src;

  to = (blt_int8u *)dest;

  /* copy all bytes from source address to destination address */

  while(len-- > 0)

  {

    /* store byte value from source to destination */

    *to++ = *from++;

    /* keep the watchdog happy */

    CopService();

  }

} /*** end of CpuMemCopy ***/

/************************************************************************************//**

** \brief     Perform a soft reset of the microcontroller by starting from the reset ISR.

** \return    none.

**

****************************************************************************************/

void CpuReset(void)

{

  /* perform a software reset by calling the reset ISR routine */

  reset_handler();

} /*** end of CpuReset ***/

/*********************************** end of cpu.c **************************************/