Hello, I have been developing a firmware application for our STM32F746 – based product. The idea idea to have a bootloader code that can do firmware update and/or jump to the application. I have been using IAR Embedded Workbench for my development, with Cortex-M7 / ST STM32F746VG as target CPU The bootloader code is loaded at address 0x08000000, and the application – at address 0x08080000 in internal flash. This is my initial buttloader code; it is not using any external libraries, and not doing any extra operations yet (this would be added later): //—— /* STM32F746 Flash: 0x08000000 – 0x080FFFFF (1 MB) Bootloader: 0x08000000 – 0x0807FFFF (5212KB) Application: 0x08080000 – 0x080FFFFF (512KB) */

include <stdio.h>**

include <stdint.h>

include <intrinsics.h>

include “stm32f7xx.h” // STM32F746VG Cortex-M7 Device

include <core_cm7.h> // STM32F746VG Cortex-M7 Core

typedef void (application_t) (void); extern const uint32t appvector; // Application vector address symbol from // the linker configuration file: 0x08080000 typedef struct vector { uint32t stackaddr; // intvec[0] is initial Stack Pointer applicationt *funcp; // intvec[1] is initial Program Counter } vector_t; int main(void) { const vectort *vectorp = (vectort*) &appvector; volatile uint32t stackarr[100] = {0}; // Allocate some stack just to show that // the SP should be reset before the jump – or the // stack won’t be configured correctly. __enableinterrupt(); printf(“Hello from bootloader!n”); __disableinterrupt(); // 1. Disable interrupts __setSP(vectorp->stackaddr); // 2. Configure stack pointer SCB->VTOR = (uint32t) &appvector; // 3. Configure VTOR vectorp->func_p(); // 4. Jump to application } //—— And this is my application’ main() function; it is using STM HALL library ant FreeRTOS libtrary (it is a multitasking application) //—— int main(void) { printf(“Hello from application!n”);

/* Enable the CPU Cache */
CPU_CACHE_Enable();

/* Reset of all peripherals, Initializes the Flash interface and the Systick. */ HAL_Init();

/* Configure the system clock */
SystemClock_Config();

/* Several modules initialization */
/* ...... */

/* Call init function for freertos objects (in freertos.c) */
MX_FREERTOS_Init();

/* Start scheduler */
osKernelStart();

/* We should never get here as control is now taken by the scheduler */
while ( 1 );

} //—— The jump to application is successfull, and everything executes ok until “MXFREERTOSInit();” I was able to trace the issue to: MXFREERTOSInit() -> myMutex01Handle = osMutexCreate(osMutex(myMutex01)); -> return xSemaphoreCreateMutex(); = xQueueCreateMutex( queueQUEUETYPEMUTEX ); -> xQueueGenericCreate( uxMutexLength, uxMutexSize, ucQueueType ); -> pvPortMalloc( sizeof( Queuet ) + xQueueSizeInBytes ); -> ( void ) xTaskResumeAll(); -> taskENTERCRITICAL() = portENTERCRITICAL() = vPortEnterCritical() -> portDISABLEINTERRUPTS(); // stalls here! I broke the last macro into containing functions: __disableinterrupt();
__setBASEPRI( configMAXSYSCALLINTERRUPTPRIORITY );
__DSB();
__ISB();
__enableinterrupt(); The code run stalls in the last instruction: __enable_interrupt(); Any idea what can be frong? Note: If the application is loaded at address 0x08000000 (no bootloader), it runs OK. -Thanks!

As the issue occurs when you enable the interrupt – is it possible that as soon as interrupts are enabled an interrupt actually executes, but not an interrupt that you expect? Perhaps using the wrong vector table, or something similar?