Regarding HBA device with boot disk support

What are the parameters the BIOS passes to the Windows OS during the installation time in order to identify the boot capable disks that is connected to an SAS HBA(PCIe Endpoint). Assume the HBA can be used to connect multiple sas and sata drives, and the controller can expose limited number of drives as bootable devices to the OS as chosen by the user(using bios and controller configuration utility).
The storport doesn’t seems to be querying for that information, and according to my understanding the windows OS comparing the information received from the bios with the
information received from storport(like controller identifier, Bus, Target, Lun) after enumeration and discovery process of the drives connected to the controller, in order to identify the boot capability of the drives.