Here is the output from my Centos box, doesn't list firmware but the drive is now detected. I took roughly 1.5 hours to format. I will report back if they work in freenas.
[root@localhost ~]# smartctl -i /dev/sdb
smartctl 6.5 2016-05-07 r4318 [x86_64-linux-3.10.0-862.el7.x86_64] (local build)
Copyright (C) 2002-16, Bruce Allen, Christian Franke,
www.smartmontools.org
=== START OF INFORMATION SECTION ===
Vendor: HITACHI
Product: DKR5C-J600SS
Revision: AUAU
Compliance: SPC-4
User Capacity: 600,127,266,816 bytes [600 GB]
Logical block size: 512 bytes
Rotation Rate: 10020 rpm
Form Factor: 2.5 inches
Logical Unit id: 0x5000cca025a15a00
Serial number: PVJVRVXB
Device type: disk
Transport protocol: SAS (SPL-3)
Local Time is: Thu Nov 1 14:44:29 2018 EDT
SMART support is: Available - device has SMART capability.
SMART support is: Enabled
Temperature Warning: Enabled