** Description changed:

  [Impact]
- It cannot enable LAN when connecting with Realtek RTL8116AF SFP option module.
+ LAN does not work when using Realtek RTL8116AF SFP option module. Network
+ interface stays down — no link, no connectivity. Hits 100% on affected
+ hardware.
+ RTL8116AF is a variant of RTL8168fp that uses SerDes instead of PHY for
+ link status. The r8169 driver reads PHY registers for link state, but
+ SerDes status is not reflected in those registers on RTL8116AF. The driver
+ sees no link even when the cable is connected and the SerDes link is up.
  
  [Fix]
- Realtek provides a patch to fix this issue.
+ Add a quirk for RTL8116AF that reflects SerDes status during PHY register
+ reads. A detection function identifies RTL8116AF by MAC version and OCP
+ register values. When detected, the MDIO read path ORs in the SerDes link
+ status (BMSR and PHYSR registers) so the driver sees the correct link
+ state.
+ Patch from Realtek, posted to lkml, not merged upstream yet:
+ https://lore.kernel.org/lkml/[email protected]/
  
- [Test]
- 1.Connect transceiver and network cable to SFP option module.
- 2.Boot to OS.
- 3.Ping SUT and the network should work
+ [Test Plan]
+ 1. Connect transceiver and network cable to SFP option module with
+    RTL8116AF chip.
+ 2. Boot to OS.
+ 3. Check link status:
+    $ ip link show
+ Without patch: interface shows NO-CARRIER, no link detected.
+ With patch: interface shows link up, ping works.
  
  [Where problems could occur]
- The patch is dedicated for 8116 chip
+ Could break r8169 ethernet driver on RTL8168fp-based chips.
+ The detection function rtl_is_8116af() checks mac_version and two OCP
+ registers. If those register values match on a non-8116AF chip, the quirk
+ would OR wrong values into PHY reads. This could report a false link-up
+ or wrong speed on that chip.
+ The quirk also changes the MDIO read path for MAC versions
+ RTL_GIGA_MAC_VER_40 through RTL_GIGA_MAC_VER_LAST, so any future MAC
+ version that shares the same OCP register pattern would be affected.

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https://bugs.launchpad.net/bugs/2116144

Title:
  Realtek RTL8116AF SFP option module fails to get connected

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