const struct spi_flash *boot_device_spi_flash(void)
{
	boot_device_rw_init();

	if (car_get_var(sfg_init_done) != true)
		return NULL;

	return car_get_var_ptr(&sfg);
}
const struct region_device *boot_device_rw(void)
{
	/* Probe for the SPI flash device if not already done. */
	boot_device_rw_init();

	if (car_get_var(sfg) == NULL)
		return NULL;

	return &spi_rw;
}
const struct spi_flash *boot_device_spi_flash(void)
{
	boot_device_rw_init();
	return car_get_var(sfg);
}