_NVIC_SystemReset stuck in infinite loop when calling pm_reboot through shell after flashing with J-Link #13044
Description
For some curious reason, after flashing several openmote-b nodes with a J-Link programmer, trying to reboot said nodes via the shell "reboot" command causes those nodes to hang forever. I verified that the infinite for loop in cpu/cortexm_common/include/vendor/core_cm3.h is reached as it's supposed to while awaiting a reset. However, this reset actually never occurs, causing the node to hang forever. I also tested this with openmote-b nodes that where only ever flashed via USB and they work just fine. This issue persists even after disconnecting the J-Link programmer and, worse, after reflashing the node via USB. As such I suspect that flashing over J-Link writes to certain registers that are otherwise untouched when flashing over USB.
__NO_RETURN __STATIC_INLINE void __NVIC_SystemReset(void)
{
__DSB(); /* Ensure all outstanding memory accesses included
buffered write are completed before reset */
SCB->AIRCR = (uint32_t)((0x5FAUL << SCB_AIRCR_VECTKEY_Pos) |
(SCB->AIRCR & SCB_AIRCR_PRIGROUP_Msk) |
SCB_AIRCR_SYSRESETREQ_Msk ); /* Keep priority group unchanged */
__DSB(); /* Ensure completion of memory access */
for(;;) /* wait until reset */
{
/* this loop is called infinitely until reset, which never
happens and thus causes the node to hang forever */
__NOP();
}
}