bootloader.c

开发板AT91SAM9260-EK的测试程序

/******************************************************************************/
/*  This file is part of the ARM Toolchain package                            */
/*  Copyright KEIL ELEKTRONIK GmbH 2005 - 2007                                */
/******************************************************************************/
/*                                                                            */
/*  Bootloader.C 2-nd level bootloader for AT91SAM926x Devices                */
/*                                                                            */
/******************************************************************************/

#include <AT91SAM9260.H>                // AT91SAM9260 definitions
#include <lib_AT91SAM9260.h>            // Library function definitions
#include "FlashHW.h"
#include "Error.h"                      // Error definitions

#define STACK_SIZE   64                 // Stack Size

#define DF_OFFSET    0x4200             // User Program offset in DataFlash
#define EXT_SDRAM    (0x20000000)       // Start address of external SDRAM

// Pointer to start of the External SDRAM where Application is copied
typedef void (*fnc)(void);
const fnc AppEntry = (fnc) EXT_SDRAM;


/**************************** Auxiliary Functions ******************************/

/*- GetProgramSize () ----------------------------------------------------------
 *
 *  Get size of user program to be copied
 *    Parameter:
 *    Return Value:  size in bytes
 */

static unsigned int GetProgramSize (void) {
  
  unsigned char buf[32];

  ReadPage_HW(DF_OFFSET, 32, buf);

  return (*(unsigned long *)&buf[0x14]);
}


/*************************** 2-nd Level Bootloader *****************************/

/*- main () --------------------------------------------------------------------
 *
 *  C routine for DataFlash Initialization and copying code from External Flash
 *  to External SDRAM
 *    Parameter:
 *    Return Value:   0 - OK,  1 - Failed
 */
           
int main (void) {

  unsigned long prog_size, page_size;
  unsigned long i;

  InitFlashController_HW(0, 0, 0, 18432000);

  // Copy code from External Flash to External SDRAM
  prog_size  = GetProgramSize ();       // Number of bytes to copy
  if (prog_size == 0xFFFFFFFF)          // If no program exists in Ext Flash
    return (1);                         // then Exit bootloader

  // Get page size for copying
  page_size  = (unsigned long) GetPageSize_HW();

  // If button BP4 is pressed while power-up then erase the flash reserved 
  // for 2-nd level bootloader
  *AT91C_PIOA_PPUER = AT91C_PIO_PA31;
  if (!(*AT91C_PIOA_PDSR & AT91C_PIO_PA31)) {
    for (i = 0; i < DF_OFFSET; i += page_size)
      ErasePage_HW(i);
    return (1);                         // Exit bootloader
  }

  // Copy code from External Flash to External SDRAM
  for (i = 0; i < prog_size; i += page_size)
    ReadPage_HW(DF_OFFSET+i, page_size, (unsigned char *)(EXT_SDRAM+i));

  // Leave only PIOC enabled (needed for External SDRAM)
  *AT91C_PMC_PCER &= (1 << AT91C_ID_PIOC);

  AppEntry();                           // Start the copied Application

  return (0);
}

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