From: Voon Weifeng <redacted>

This patch-set is to enable Ethernet controller
(DW Ethernet QoS and DW Ethernet PCS) with SGMII interface in Elkhart Lake.
The DW Ethernet PCS is the Physical Coding Sublayer that is between Ethernet
MAC and PHY and uses MDIO Clause-45 as Communication.

Selttests results:
root@intel-corei7-64:~# ethtool -t eth0
The test result is PASS
The test extra info:
 1. MAC Loopback                 0
 2. PHY Loopback                 -95
 3. MMC Counters                 0
 4. EEE                          -95
 5. Hash Filter MC               0
 6. Perfect Filter UC            0
 7. MC Filter                    0
 8. UC Filter                    0
 9. Flow Control                 0

Thanks for testing and addressing all review comments!

Acked-by: Jose Abreu <redacted>

Thanks,
Jose Miguel 
Abreu