Hi
in order to use auto tiering capabilities you must create a virtual pool (there can be only 2 virtual pools one on controller A and one on controller B)
I understand that you have 12 disks of 600GB and 2 SSD disks so your option is to create one virtual pool A in it you have the first virtual disk group of 12 SAS disks and then add to it a virtual disk group with the 2 SSD disks. this will be your performance tier.
if you want to split activity between 2 controllers you need more SSD disks and then to create two virtual pools with 2 virtual disk groups in each pool.
Regards
if this helps give a KUDO