Bootloader jump to app not working on STM32G491

[Yves Bmnt]

Hi all,

I am trying to launch the app from a bootloader code that I copied from a project on an STM32L0 and STM32F446, it worked fine there but somehow my app doesn't start on the STM32G491.

Here's the code for the jump:

 

 

static void bootloader_jump_to_app(void)
{
 uint32_t JumpAddress = *(__IO uint32_t*)(APP_ADDRESS + 4u);

 pFunction Jump = (pFunction)JumpAddress;


 if (!bootloader_check_integrity())
 {
 bootloader_send_message("Abort\r", 8u);
 bootloader_init();
 }
 else
 {
		bootloader_send_message("Starting\r", 9u);

		HAL_FLASH_Lock(); // lock flash after memory erase + write

		HAL_RCC_DeInit();
		HAL_DeInit();

		SysTick->CTRL = 0u;
		SysTick->LOAD = 0u;
		SysTick->VAL = 0u;

		SCB->VTOR = (__IO uint32_t)APP_ADDRESS;

		__set_MSP(*(__IO uint32_t*)APP_ADDRESS);

		Jump();
		while(1);
 }
}

 

 

I have modified my .ld file accordingly with app start address 0x08003000, I compared the memory part with the app to the bin file and it's similar, I don't understand where the problem comes from, even though I noticed some differences in the APIs between STM32L0 and G4 series, all the code examples seem to match, or maybe I missed something, can anybody help please?

[Imen.D]

Hello @Yves Bmnt ,

Please have a look at this article How to jump to system bootloader from application ... - STMicroelectronics Community. This will help you to jump to system bootloader from application code.

 

 

[Yves Bmnt]

thank you for your quick answer.

After reading the article, I modified my code to this, but the app doesn't run somehow. Also, I don't understand why my original code works with STM32L010 & STM32F446 but not with STM32G491.

 

 

static void bootloader_jump_to_app(void)
{
 uint32_t JumpAddress = *(__IO uint32_t*)(APP_ADDRESS + 4u), i= 0u;

 pFunction Jump = (pFunction)JumpAddress;


 if (!bootloader_check_integrity())
 {
 bootloader_send_message("Abort\r", 8u);
 bootloader_init();
 }
 else
 {
		bootloader_send_message("Starting\r", 9u);

		HAL_FLASH_Lock(); // lock flash after memory erase + write

		/* Disable all interrupts */
		__disable_irq();

		HAL_RCC_DeInit();
		//HAL_DeInit();

		SysTick->CTRL = 0u;
		//SysTick->LOAD = 0u;
		//SysTick->VAL = 0u;

		/* Clear Interrupt Enable Register & Interrupt Pending Register */
		for (i=0;i<5;i++)
		{
			NVIC->ICER[i]=0xFFFFFFFF;
			NVIC->ICPR[i]=0xFFFFFFFF;
		}

		/* Re-enable all interrupts */
		__enable_irq();

		//SCB->VTOR = (__IO uint32_t)APP_ADDRESS;

		__set_MSP(*(__IO uint32_t*)APP_ADDRESS);

		Jump();
		while(1);
 }
}

 

 

[gbm]

Check the assembly code generated for the above routine (your project .list file). If there is any instruction using sp register between the MSM setting code and jumping to application, it will fail. If this is the case - use -O2 optimization level, which should solve the problem. Also, leave the VTOR setting statement uncommented.

[Imen.D]

Noted in the AN2606:

"On devices with dual bank boot, to jump to system memory from user code the user must first remap the system memory bootloader at address 0x00000000 using SYSCFG register (except for STM32F7 series), then jump to bootloader..."

So to jump, try adding this line in your code just before jumping:

SYSCFG->MEMRMP = 0x01;

Hope this helps ! Please, let me know about your progress on this issue.

[Yves Bmnt]

I placed this line right before the Jump(); but it didn't work :(

[MM..1]

Primary test start app from stlink change to your hex and address

"C:\Program Files\STMicroelectronics\STM32Cube\STM32CubeProgrammer\bin\STM32_Programmer_CLI.exe" -c port=SWD mode=UR -d ledtest.hex -v -g 0x08004000

 

[Imen.D]

Did you try to alter the linker script for the application and change the Flash origin?

As you see in AN4767 that when FB_MODE is set, the addresses are remapped:

 

[Yves Bmnt]

sure, I use 0x08003000 as Flash origin:

/* Memories definition */
MEMORY
{
 RAM (xrw) : ORIGIN = 0x20000000, LENGTH = 112K
 FLASH (rx) : ORIGIN = 0x8003000, LENGTH = 244K
}

 

[FShah.1]

Hi,

I will appreciate your prompt response. I found the issue in my code, and now the CRC is working correctly.

However, another problem has arisen. As you know, I am working on a bootloader program. My application code is successfully transferred from the source to the controller via the serial port. But when the code attempts to set the reset handler and jump to the application code, it is failing.

I am using the STM32F446 microcontroller.

First, I copied the code to memory address 0x08040000. Then, bootloader copied to the application memory address, which is 0x08020000. The CRC of the application on the host side, the CRC at address 0x08040000, and the CRC at address 0x08020000 are all the same.

I checked the memory locations, and they have the same data. However, the jump_to_application function is not successful.

Blink LED Application: I changed the Flash address in linker file

/* Memories definition */

MEMORY

{

RAM (xrw) : ORIGIN = 0x20000000, LENGTH = 128K

FLASH (rx) : ORIGIN = 0x08020000, LENGTH = 128K

}

 

/*!< Uncomment the following line if you need to relocate the vector table

anywhere in Flash or Sram, else the vector table is kept at the automatic

remap of boot address selected */

#define USER_VECT_TAB_ADDRESS

 

#if defined(USER_VECT_TAB_ADDRESS)

/*!< Uncomment the following line if you need to relocate your vector Table

in Sram else user remap will be done in Flash. */

/* #define VECT_TAB_SRAM */

#if defined(VECT_TAB_SRAM)

#define VECT_TAB_BASE_ADDRESS SRAM_BASE /*!< Vector Table base address field.

This value must be a multiple of 0x200. */

#define VECT_TAB_OFFSET 0x00000000U /*!< Vector Table base offset field.

This value must be a multiple of 0x200. */

#else

#define VECT_TAB_BASE_ADDRESS FLASH_BASE /*!< Vector Table base address field.

This value must be a multiple of 0x200. */

#define VECT_TAB_OFFSET 0x00020000U /*!< Vector Table base offset field.

This value must be a multiple of 0x200. */

#endif /* VECT_TAB_SRAM */

#endif /* USER_VECT_TAB_ADDRESS */

 

 

Bootloader: jump_to_application function:

static void goto_application(void)

{

 

printf("Gonna Jump to Application\r\n");

 

 

 

// Set the Vector Table Offset Register (VTOR) to the address of the application

SCB->VTOR = ETX_APP_FLASH_ADDR;

// Get the application reset handler address

void (*app_reset_handler)(void) = (void*)(*((volatile uint32_t*) (ETX_APP_FLASH_ADDR + 4U)));//Application starting address

// Optionally turn off the LED

HAL_GPIO_WritePin(GPIOD, GPIO_PIN_2, GPIO_PIN_RESET);

 

/* Reset the Clock */

HAL_RCC_DeInit();

HAL_DeInit();

__set_MSP(*(volatile uint32_t*) ETX_APP_FLASH_ADDR);

SysTick->CTRL = 0;

SysTick->LOAD = 0;

SysTick->VAL = 0;

 

/* Jump to application */

app_reset_handler();    //call the app reset handler

}

Kindly advise on how to solve this problem. I am very close to the finish line, but something I am doing seems to be wrong! Please help. Thank you

0 Kudos

 

Accept as Solution 

Reply

 

 

[gbm]

See my remark in this thread, below the main article:

https://community.st.com/t5/stm32-mcus/how-to-share-an-api-between-a-bootloader-and-an-application/ta-p/736681

- check the code generated by the compiler, maybe change optimization level.

[FShah.1]

I appreciate your response.

I checked the memory regions where the code is being written and identified an issue with how the data was being written to the flash memory—specifically, little-endian / big-endian issue. After addressing this, the application is now successfully loading and working.

Thanks for being responsive. I will reach out to you for assistance with other parts of the bootloader process during my development.

Thanks again,
FS