The HBAs must support INT13 BIOS extensions. You also need to enable the HBAs Boot BIOS and make sure the server's BIOS Boot order is correct. Beyond this you should have LUNs assigned, and a WWN, etc. so that the HBA is related to a storage partition somewhere on the SAN.
This allows the HBAs to present the storage during Boot time. At that point our provisioning process will view the storage the same as locally attached drives.
I'm not sure what operating system you are trying to provision, but this Microsoft Whitepaper covers key principles that you may want to think about
I am in the same state and very much interested to know how provisioing of Boot from SAN server be used for AIX.
Any feedback is much appreciated.