cancel
Showing results for 
Search instead for 
Did you mean: 

STM32H743ZI: Can't change where DMA Buffers are stored in memory region

CLeo.1
Senior II

Hi Guys,

I am in the mist of changing my linker file as I just recently found out that my DMA buffers are located in 0x2001FF0C region which is the DTCM (DMA can't access this region).

I have tried changing the "RAM" to "RAM_D2" that didn't do anything.

The only way I got it to change was change the DMA buffer to a static then change the linker, however I dont want it to be static.

I also notice when I change any of the linker .bss or .data anytime I try to insert a new() into an array it hardfaults now.

Linker file:

/*
******************************************************************************
**
**  File        : LinkerScript.ld
**
**  Author      : STM32CubeIDE
**
**  Abstract    : Linker script for STM32H7 series
**                2048Kbytes FLASH and 192Kbytes RAM
**
**                Set heap size, stack size and stack location according
**                to application requirements.
**
**                Set memory bank area and size if external memory is used.
**
**  Target      : STMicroelectronics STM32
**
**  Distribution: The file is distributed as is, without any warranty
**                of any kind.
**
*****************************************************************************
** @attention
**
** Copyright (c) 2019 STMicroelectronics.
** All rights reserved.
**
** This software component is licensed by ST under BSD 3-Clause license,
** the "License"; You may not use this file except in compliance with the
** License. You may obtain a copy of the License at:
**                        opensource.org/licenses/BSD-3-Clause
**
****************************************************************************
*/
 
/* Entry Point */
ENTRY(Reset_Handler)
 
/* Highest address of the user mode stack */
_estack = 0x20020000;    /* end of RAM */
/* Generate a link error if heap and stack don't fit into RAM */
_Min_Heap_Size = 0x200 ;      /* required amount of heap  */
_Min_Stack_Size = 0x400 ; /* required amount of stack */
 
/* Specify the memory areas */
MEMORY
{
  FLASH (rx)     : ORIGIN = 0x08000000, LENGTH = 2048K
  RAM (xrw)      : ORIGIN = 0x20000000, LENGTH = 128K
  RAM_D1 (xrw)   : ORIGIN = 0x24000000, LENGTH = 512K
  RAM_D2 (xrw)   : ORIGIN = 0x30000000, LENGTH = 288K
  RAM_D3 (xrw)   : ORIGIN = 0x38000000, LENGTH = 64K
  ITCMRAM (xrw)  : ORIGIN = 0x00000000, LENGTH = 64K
}
 
/* Define output sections */
SECTIONS
{
  /* The startup code goes first into FLASH */
  .isr_vector :
  {
    . = ALIGN(4);
    KEEP(*(.isr_vector)) /* Startup code */
    . = ALIGN(4);
  } >FLASH
 
  /* The program code and other data goes into FLASH */
  .text :
  {
    . = ALIGN(4);
    *(.text)           /* .text sections (code) */
    *(.text*)          /* .text* sections (code) */
    *(.glue_7)         /* glue arm to thumb code */
    *(.glue_7t)        /* glue thumb to arm code */
    *(.eh_frame)
 
    KEEP (*(.init))
    KEEP (*(.fini))
 
    . = ALIGN(4);
    _etext = .;        /* define a global symbols at end of code */
  } >FLASH
 
  /* Constant data goes into FLASH */
  .rodata :
  {
    . = ALIGN(4);
    *(.rodata)         /* .rodata sections (constants, strings, etc.) */
    *(.rodata*)        /* .rodata* sections (constants, strings, etc.) */
    . = ALIGN(4);
  } >FLASH
 
  .ARM.extab   : { *(.ARM.extab* .gnu.linkonce.armextab.*) } >FLASH
  .ARM : {
    __exidx_start = .;
    *(.ARM.exidx*)
    __exidx_end = .;
  } >FLASH
 
  .preinit_array     :
  {
    PROVIDE_HIDDEN (__preinit_array_start = .);
    KEEP (*(.preinit_array*))
    PROVIDE_HIDDEN (__preinit_array_end = .);
  } >FLASH
  .init_array :
  {
    PROVIDE_HIDDEN (__init_array_start = .);
    KEEP (*(SORT(.init_array.*)))
    KEEP (*(.init_array*))
    PROVIDE_HIDDEN (__init_array_end = .);
  } >FLASH
  .fini_array :
  {
    PROVIDE_HIDDEN (__fini_array_start = .);
    KEEP (*(SORT(.fini_array.*)))
    KEEP (*(.fini_array*))
    PROVIDE_HIDDEN (__fini_array_end = .);
  } >FLASH
 
  /* used by the startup to initialize data */
  _sidata = LOADADDR(.data);
 
  /* Initialized data sections goes into RAM, load LMA copy after code */
  .data :
  {
    . = ALIGN(4);
    _sdata = .;        /* create a global symbol at data start */
    *(.data)           /* .data sections */
    *(.data*)          /* .data* sections */
    *(.RamFunc)        /* .RamFunc sections */
    *(.RamFunc*)       /* .RamFunc* sections */
 
    . = ALIGN(4);
    _edata = .;        /* define a global symbol at data end */
  } >RAM AT> FLASH
 
  /* Uninitialized data section */
  . = ALIGN(4);
  .bss :
  {
    /* This is used by the startup in order to initialize the .bss secion */
    _sbss = .;         /* define a global symbol at bss start */
    __bss_start__ = _sbss;
    *(.bss)
    *(.bss*)
    *(COMMON)
 
    . = ALIGN(4);
    _ebss = .;         /* define a global symbol at bss end */
    __bss_end__ = _ebss;
  } >RAM
 
  /* User_heap_stack section, used to check that there is enough RAM left */
  ._user_heap_stack :
  {
    . = ALIGN(8);
    PROVIDE ( end = . );
    PROVIDE ( _end = . );
    . = . + _Min_Heap_Size;
    . = . + _Min_Stack_Size;
    . = ALIGN(8);
  } >RAM
 
  /* Remove information from the standard libraries */
  /DISCARD/ :
  {
    libc.a ( * )
    libm.a ( * )
    libgcc.a ( * )
  }
 
  .ARM.attributes 0 : { *(.ARM.attributes) }
}
 
 
Where DMA buffer gets delcared
/*
 * CLI.h
 *
 *  Created on: Sep 22, 2021
 *      Author: Chris
 */
 
#ifndef TOOLS_CLI_CLI_H
#define TOOLS_CLI_CLI_H
 
#include <stdint.h>
 
#include "stm32h743xx.h"
#include "../../Constants/projectConfigure.h"
#include "../../Constants/functionReturnStates.h"
#include "../../Drivers/STM32H7xx_HAL_Driver/Inc/stm32h7xx_ll_usart.h"
#include "../../Drivers/STM32H7xx_HAL_Driver/Inc/stm32h7xx_ll_bus.h"
#include "../../Drivers/STM32H7xx_HAL_Driver/Inc/stm32h7xx_ll_dma.h"
#include "../../Drivers/STM32H7xx_HAL_Driver/Inc/stm32h7xx_ll_gpio.h"
#include "CMD/CMD.h"
 
class CLI {
 
private:
	 char CLI_TxBuff[CLI_buffLength] = {0};
	 char CLI_RxBuff[CLI_buffLength] = {0};
	 uint32_t baudRate;
 
	void enableTx();
 
public:
 
	CLI();
	void execute(CMD * CMDs, char * CLI_TxBuff);
	char * getCLITxBuff(void);
};
 
 
 
#endif /* TOOLS_CLI_CLI_H_ */

1 ACCEPTED SOLUTION

Accepted Solutions
TDK
Guru

Replace all three instances of ">RAM" with ">RAM_D1" and change the _estack definition to "_estack = ORIGIN(RAM_D1) + LENGTH(RAM_D1);"

If you feel a post has answered your question, please click "Accept as Solution".

View solution in original post

4 REPLIES 4
TDK
Guru

Replace all three instances of ">RAM" with ">RAM_D1" and change the _estack definition to "_estack = ORIGIN(RAM_D1) + LENGTH(RAM_D1);"

If you feel a post has answered your question, please click "Accept as Solution".

Well, that did it good sir, went from 0x2001 -> 0x2400

CLeo.1
Senior II

@TDK​ Only problem now is that the DMA isnt transferring anything from the buffer to the peripheral