#include "boot_port.h"
#include "stm32f4xx_hal.h"
#define REQUEST_MAGIC 0x42555342UL
static uint32_t reset_at;
static bool reset_pending;
static void backup_access(void)
{
    __HAL_RCC_PWR_CLK_ENABLE();
    PWR->CR |= PWR_CR_DBP;
    __HAL_RCC_RTC_ENABLE();
}
bool f407_boot_requested(void)
{
    bool requested;
    backup_access(); requested=RTC->BKP0R==REQUEST_MAGIC;
    RTC->BKP0R=0; return requested;
}
void f407_request_boot(uint32_t now)
{
    backup_access(); RTC->BKP0R=REQUEST_MAGIC;
    reset_at=now+500; reset_pending=true;
}
void f407_reset_poll(uint32_t now)
{
    if(reset_pending && (int32_t)(now-reset_at)>=0) NVIC_SystemReset();
}