Heap memory location

#include <stdlib.h>

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

// Keil uv4 MICROLIB compatible heap initialization

extern unsigned long __microlib_freelist;

extern unsigned long __microlib_freelist_initialised;

extern unsigned long __heap_base;

extern unsigned long __heap_limit;

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

void add_heap(unsigned long addr, unsigned long size)

{

  unsigned long *p = (unsigned long *)addr;

  unsigned long span;

  size >>= 2; // size in 32-bit words

  size -= 2; // two words used for internal structures

  if (__microlib_freelist_initialised == 0) // free list created yet?

  {

    __microlib_freelist_initialised = 1;

    __microlib_freelist = 0;

    span = 0;

  }

  else

  {

    span = __microlib_freelist - addr - (size << 2); // faux allocation across the discontinuity

  }

  p[0] = size << 2;           // size of list entry

  p[1] = __microlib_freelist; // next entry

  p[size] = span;

  p[size+1] = 0;              // terminal value

  __microlib_freelist = addr; // current entry

}

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

void alloc_heaps(void) // Called prior to any malloc()

{

  // Enumerate available heap memory regions in DECENDING memory order

//add_heap(0xD0000000, 0x800000); // SDRAM 8MB - Must be initialized

  add_heap((unsigned long)&__heap_base,(unsigned long)&__heap_limit - (unsigned long)&__heap_base); // Classic HEAP section

//  add_heap(0x20004000, 0x14000); // SRAM (PORTION OF)

  add_heap(0x10000000, 0x10000); // CCM 64K

}







===============================================================================




// STM32 Keil SDRAM HEAP STM32F429I-DISCO

// Use MicroLIB checked in options

// Use Scatter file in Linker options (not Memory Layout from Target Dialog)

/* heap.sct

LR_IROM1 0x08000000 0x00200000  {    ; load region size_region

  ER_IROM1 0x08000000 0x00200000  {  ; load address = execution address

   *.o (RESET, +First)

   *(InRoot$$Sections)

   .ANY (+RO)

  }

  RW_IRAM1 0x20000000 0x00030000  {  ; Internal SRAM

   .ANY (+RW +ZI)

  }

  RW_IRAM2 0x10000000 UNINIT 0x00010000  {  ; Internal CCM SRAM

   *(.ccm)

  }

  RW_RAM1 0xD0000000 UNINIT 0x00800000  { ; External SDRAM

   *(HEAP)

  }

}

*/

/* startup_stm32f429_439xx.s

...

Heap_Size       EQU     0x00800000

                AREA    HEAP, NOINIT, READWRITE, ALIGN=3

__heap_base

Heap_Mem        SPACE   Heap_Size

__heap_limit

...

*/

#include <stdio.h>

#include <stdlib.h>

#include "stm32f429i_discovery.h"

#include "stm32f429i_discovery_sdram.h"

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

int main(void)

{

  char *p;

  /* Make sure to initialize the external memory, pins and buses before using them */

  /* SDRAM Initialization */

  SDRAM_Init();

  /* Disable write protection */

  FMC_SDRAMWriteProtectionConfig(FMC_Bank2_SDRAM,DISABLE);

  p = malloc(0x1000);

  printf("Allocation at %p\n", p);

  free(p);

  while(1); // Don't want to exit

}

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

// Hosting of stdio functionality through SWV - Serial Wire Viewer

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

#include <rt_misc.h>

#pragma import(__use_no_semihosting_swi)

struct __FILE { int handle; /* Add whatever you need here */ };

FILE __stdout;

FILE __stdin;

int fputc(int ch, FILE *f)

{

  ITM_SendChar(ch);

  return(ch);

}

int fgetc(FILE *f)

{

  char ch;

  ch = '?';

  return((int)ch);

}

int ferror(FILE *f)

{

  /* Your implementation of ferror */

  return EOF;

}

void _ttywrch(int ch)

{

  ITM_SendChar(ch);

}

void _sys_exit(int return_code)

{

label:  goto label;  /* endless loop */

}

#ifdef  USE_FULL_ASSERT

/**

  * @brief  Reports the name of the source file and the source line number

  *         where the assert_param error has occurred.

  * @param  file: pointer to the source file name

  * @param  line: assert_param error line source number

  * @retval None

  */

void assert_failed(uint8_t* file, uint32_t line)

{

  /* User can add his own implementation to report the file name and line number,

     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */

  /* Infinite loop */

  while (1)

  {

  }

}

#endif













For FREERTOS




__attribute__((section("HEAP"))) static unsigned char ucHeap[ configTOTAL_HEAP_SIZE ];