flash linker script for STM32H750IBT6 with external QUADSPI and SDRAM for TouchGFX

[AEng7]

I am using below component tools

MCU: STM32H750IBT6

IDE: STM32CubeIDE Version: 1.20.0

GUI: TouchGFX Version: 4.26.0

SDRAM: IS42S32400J-6TLI

FLASH: MT25QL512ABB8ESF-0SIT (QUADSPI)

 

I have made my own external loader that proves works for the QUADSPI IC using this video: https://www.st.com/content/st_com/en/support/learning/stm32-education/stm32-moocs/external_QSPI_loader.html

 

Thank you in advance!

[mƎALLEm]

Hello,

You can inspire from one of the linker scripts generated by TouchGFX Designer starring from TBS board (in this case STM32H750I-DISCO board):

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

** File : LinkerScript.ld
**
** Author		: STM32CubeMX
**
** Abstract : Linker script for STM32H750XBHx series
** 128Kbytes FLASH and 1056Kbytes 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
**
** <h2><center>&copy; COPYRIGHT(c) 2025 STMicroelectronics</center></h2>
**
** Redistribution and use in source and binary forms, with or without modification,
** are permitted provided that the following conditions are met:
** 1. Redistributions of source code must retain the above copyright notice,
** this list of conditions and the following disclaimer.
** 2. Redistributions in binary form must reproduce the above copyright notice,
** this list of conditions and the following disclaimer in the documentation
** and/or other materials provided with the distribution.
** 3. Neither the name of STMicroelectronics nor the names of its contributors
** may be used to endorse or promote products derived from this software
** without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
** DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
** OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**
*****************************************************************************
*/

/* Entry Point */
ENTRY(Reset_Handler)

/* Specify the memory areas */
MEMORY
{
 DTCMRAM (xrw) : ORIGIN = 0x20000000, LENGTH = 128K
 ITCMRAM (xrw) : ORIGIN = 0x00000000, LENGTH = 64K
 RAM_D1 (xrw) : ORIGIN = 0x24000000, LENGTH = 512K
 RAM_D2 (xrw) : ORIGIN = 0x30000000, LENGTH = 288K
 RAM_D3 (xrw) : ORIGIN = 0x38000000, LENGTH = 64K
 SDRAM (xrw) : ORIGIN = 0xD0000000, LENGTH = 8M
 FLASH (rx) : ORIGIN = 0x90000000, LENGTH = 2048K
 ASSETS_FLASH (r) : ORIGIN = 0x90200000, LENGTH = 126M
 BOOTLOADER (xrw) : ORIGIN = 0x08000000, LENGTH = 128k
}

/* Highest address of the user mode stack */
_estack = ORIGIN(DTCMRAM) + LENGTH(DTCMRAM); /* end of RAM */
/* Generate a link error if heap and stack don't fit into RAM */
_Min_Heap_Size = 0x1000; /* required amount of heap */
_Min_Stack_Size = 0x1000; /* required amount of stack */

/* Link ISR vectors */
SECTIONS
{
 /* The startup code into "FLASH" Rom type memory */
 .isr_vector :
 {
 __ICFEDIT_intvec_start__ = .;
 . = ALIGN(4);
 KEEP(*(.isr_vector)) /* Startup code */
 . = ALIGN(4);
 } >FLASH
}

/* Define specific placement of memory areas */
SECTIONS
{
 TextFlashSection :
 {
 *(TextFlashSection TextFlashSection.*)
 *(.gnu.linkonce.r.*)
 . = ALIGN(0x4);
 } >ASSETS_FLASH

 FontFlashSection :
 {
 *(FontFlashSection FontFlashSection.*)
 *(.gnu.linkonce.r.*)
 . = ALIGN(0x4);
 } >ASSETS_FLASH

 ExtFlashSection :
 {
 *(ExtFlashSection ExtFlashSection.*)
 *(.gnu.linkonce.r.*)
 . = ALIGN(0x4);
 } >ASSETS_FLASH
}

/* Define output sections */
SECTIONS
{
 .bootloader :
 {
 . = ALIGN(4);
 ExtMem_Boot/bootloader.o(*)
 } >BOOTLOADER

 /* 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 (READONLY) : /* The "READONLY" keyword is only supported in GCC11 and later, remove it if using GCC10 or earlier. */
 {
 . = ALIGN(4);
 *(.ARM.extab* .gnu.linkonce.armextab.*)
 . = ALIGN(4);
 } >FLASH

 .ARM (READONLY) : /* The "READONLY" keyword is only supported in GCC11 and later, remove it if using GCC10 or earlier. */
 {
 . = ALIGN(4);
 __exidx_start = .;
 *(.ARM.exidx*)
 __exidx_end = .;
 . = ALIGN(4);
 } >FLASH

 .preinit_array (READONLY) : /* The "READONLY" keyword is only supported in GCC11 and later, remove it if using GCC10 or earlier. */
 {
 . = ALIGN(4);
 PROVIDE_HIDDEN (__preinit_array_start = .);
 KEEP (*(.preinit_array*))
 PROVIDE_HIDDEN (__preinit_array_end = .);
 . = ALIGN(4);
 } >FLASH

 .init_array (READONLY) : /* The "READONLY" keyword is only supported in GCC11 and later, remove it if using GCC10 or earlier. */
 {
 . = ALIGN(4);
 PROVIDE_HIDDEN (__init_array_start = .);
 KEEP (*(SORT(.init_array.*)))
 KEEP (*(.init_array*))
 PROVIDE_HIDDEN (__init_array_end = .);
 . = ALIGN(4);
 } >FLASH

 .fini_array (READONLY) : /* The "READONLY" keyword is only supported in GCC11 and later, remove it if using GCC10 or earlier. */
 {
 . = ALIGN(4);
 PROVIDE_HIDDEN (__fini_array_start = .);
 KEEP (*(SORT(.fini_array.*)))
 KEEP (*(.fini_array*))
 PROVIDE_HIDDEN (__fini_array_end = .);
 . = ALIGN(4);
 } >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);
 } >RAM_D1 AT> FLASH

 /* Initialized TLS data section */
 .tdata : ALIGN(4)
 {
 *(.tdata .tdata.* .gnu.linkonce.td.*)
 . = ALIGN(4);
 _edata = .; /* define a global symbol at data end */
 PROVIDE(__data_end = .);
 PROVIDE(__tdata_end = .);
 } >RAM_D1 AT> FLASH

 PROVIDE( __tdata_start = ADDR(.tdata) );
 PROVIDE( __tdata_size = __tdata_end - __tdata_start );

 PROVIDE( __data_start = ADDR(.data) );
 PROVIDE( __data_size = __data_end - __data_start );

 PROVIDE( __tdata_source = LOADADDR(.tdata) );
 PROVIDE( __tdata_source_end = LOADADDR(.tdata) + SIZEOF(.tdata) );
 PROVIDE( __tdata_source_size = __tdata_source_end - __tdata_source );

 PROVIDE( __data_source = LOADADDR(.data) );
 PROVIDE( __data_source_end = __tdata_source_end );
 PROVIDE( __data_source_size = __data_source_end - __data_source );
 /* Uninitialized data section */
 .tbss (NOLOAD) : ALIGN(4)
 {
 /* This is used by the startup in order to initialize the .bss secion */
 _sbss = .; /* define a global symbol at bss start */
 __bss_start__ = _sbss;
 *(.tbss .tbss.*)
 . = ALIGN(4);
 PROVIDE( __tbss_end = . );
 } >RAM_D1

 PROVIDE( __tbss_start = ADDR(.tbss) );
 PROVIDE( __tbss_size = __tbss_end - __tbss_start );
 PROVIDE( __tbss_offset = ADDR(.tbss) - ADDR(.tdata) );

 PROVIDE( __tls_base = __tdata_start );
 PROVIDE( __tls_end = __tbss_end );
 PROVIDE( __tls_size = __tls_end - __tls_base );
 PROVIDE( __tls_align = MAX(ALIGNOF(.tdata), ALIGNOF(.tbss)) );
 PROVIDE( __tls_size_align = (__tls_size + __tls_align - 1) & ~(__tls_align - 1) );
 PROVIDE( __arm32_tls_tcb_offset = MAX(8, __tls_align) );
 PROVIDE( __arm64_tls_tcb_offset = MAX(16, __tls_align) );

 .bss (NOLOAD) : ALIGN(4)
 {
 *(.bss)
 *(.bss*)
 *(COMMON)

 . = ALIGN(4);
 _ebss = .; /* define a global symbol at bss end */
 __bss_end__ = _ebss;
 PROVIDE( __bss_end = .);
 } >RAM_D1
 PROVIDE( __non_tls_bss_start = ADDR(.bss) );

 PROVIDE( __bss_start = __tbss_start );
 PROVIDE( __bss_size = __bss_end - __bss_start );

 /* User_heap_stack section, used to check that there is enough RAM left */
 ._user_heap_stack (NOLOAD) :
 {
 . = ALIGN(8);
 PROVIDE ( end = . );
 PROVIDE ( _end = . );
 . = . + _Min_Heap_Size;
 . = . + _Min_Stack_Size;
 . = ALIGN(8);
 } >DTCMRAM



 /* Remove information from the standard libraries */
 /DISCARD/ :
 {
 libc.a:* ( * )
 libm.a:* ( * )
 libgcc.a:* ( * )
 }








 BmpCacheSection (NOLOAD) : 
 {
 *(BmpCacheSection)
 } >SDRAM

 TouchGFX_Framebuffer (NOLOAD) : 
 {
 *(TouchGFX_Framebuffer)
 } >SDRAM

 TouchGFX_Framebuffer1 (NOLOAD) : 
 {
 *(TouchGFX_Framebuffer1)
 } >SDRAM

 TouchGFX_Framebuffer2 (NOLOAD) : 
 {
 *(TouchGFX_Framebuffer2)
 } >SDRAM

 Video_RGB_Buffer (NOLOAD) : 
 {
 *(Video_RGB_Buffer)
 } >SDRAM
}

[AEng7]

Thanks for the suggestion but how do I create the bootloader?

 

Can I use the bootloader.bin file that is generated with that example or do I need to make my own as its a custom PCB?

[mƎALLEm]

If you are using custom bootloader that's another stuff not related to TouchGFX.

[mƎALLEm]

+

Add that flash loader in the Debugger/ External loaders:

[AEng7]

I have done that. I have created the 'External Loader' and I have proven it works and writes/reads to QUADSPI at memory region 0x90000000, using STM32CubeProgrammer. As shown in the Youtube tutorial.

 

I then added it to STM32CubeIDE

 

 

However, your linker script that you have provided refers to '

 BOOTLOADER (xrw) : ORIGIN = 0x08000000, LENGTH = 128k

 

Located at:

 .bootloader :
 {
 . = ALIGN(4);
 ExtMem_Boot/bootloader.o(*)
 } >BOOTLOADER

 

I am asking how is this bootloader created? 

 

I know on the STM32H750B-DK which I created a demo, used the bootloader.

However, I have a custom PCB and after creating a TouchGFX project it does not contain a bootloader.bin file, or a ExtMem_Boot.

 

ExtMem_Boot does not exist in my TouchGFX project that I created from a blank STM32CubeIDE Project. 

[AEng7]

I know its the linker script which is the last step here in getting it working.

[AEng7]

Bit confused here and can we call them by there proper names. 'External Loader' and 'Bootloader'.

 

I have created an 'External Loader' using this tutorial here for the QUADSPI Flash. https://youtu.be/YFIvJVsvIsE?si=5Pt0JuSpm3BTKfg0

 

I am questioning why a bootloader is needed at all here?

https://www.youtube.com/watch?v=ELMK35I86QE - Does not use a bootloader and uses an external flash. I know my internal flash is only 128kb.

 

Do I create the ExtMem_Boot within my main project which is creating the firmware?

[mƎALLEm]

Let me be clrear:

The "External Loader" is the application that will upload your assets either the code application/ constants to the external memories while flashing the binaries. That should have .stldr extension that you should add to your IDE.

The application loader (example: https://github.com/STMicroelectronics/STM32CubeH7/tree/master/Projects/STM32H750B-DK/Templates/ExtMem_Boot/Src) that's another stuff. As I said previously that's the boot application that boots from the internal Flash. The application is mapped at the external QSPI Flash. So you need to develop that loader by inspiring from the example provided.

If your application doesn't exceed 128KB (the size of the internal Flash), that's something you can skip and use only the internal memory for the code but for TouchGFX there are assets (images and so on..) that consumes huge memory size that need to be placed in the external memory (the QSPI memory in your case) and you need that External QSPI Flash Loader you've already developed/validated.

[AEng7]

Thanks for the explanation. Can you explain why the bootloader is needed then?