STM32G473CBT freezes jumping to bootloader
I have a custom board using the STM32G473CBT6 MCU. BOOT0 is pulled-down by a 100k resistor and is used as GPIO (output) at runtime. The firmware is generated by CubeMX, with the addition of a C++ file for the 'user' application. The board works fine, but is unable to jump to the bootloader from the main program. I use this function which works well with other boards:
void __attribute__ ((optimize(0))) enter_bootloader() {
HAL_Delay(500); // Wait a bit for the last USB packets to be sent.
CDC_deInit();
GPIO_InitTypeDef GPIO_InitStruct;
GPIO_InitStruct.Pin = USB_FWUPD_GPIO_DN | USB_FWUPD_GPIO_DP;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_LOW;
HAL_GPIO_Init(USB_FWUPD_GPIO_PORT, &GPIO_InitStruct);
USB_FWUPD_GPIO_PORT->BSRR = (USB_FWUPD_GPIO_DN | USB_FWUPD_GPIO_DP) << 16U
HAL_Delay(2000);
HAL_RCC_DeInit();
HAL_DeInit();
SysTick->CTRL = 0;
SysTick->LOAD = 0;
SysTick->VAL = 0;
// #ifndef PLATFORM_STM32_FAMILY_G4
__disable_irq();
// #endif
__HAL_RCC_SYSCFG_CLK_ENABLE();
__DSB();
__HAL_SYSCFG_REMAPMEMORY_SYSTEMFLASH();
__DSB();
__ISB();
SCB->VTOR = 0;
__set_MSP(*((uint32_t*) 0x1FFF0000));
((void (*)(void)) *((uint32_t*) 0x1FFF0004))();
for (;;);
}I left out the macros with board specifics, but the function works for F4,F7, L4, L0 & G0 MCUs.
Using SWD I can step through the function fine, it just freezes at line 32, the jump.
Tried not disabling the IRQs as suggested in this forum, no differences. Also tried setting the option byte to ignore the BOOT0 pin, no effect either. Flipping the default boot mode to DFU in the option bytes does make DFU show up on the PC, but obviously isn't workable.
Is there something G4 specific that needs changing in the above function? Or should I look elsewhere for the issue?