Intel Triple-Speed Ethernet Link detect LED lines malfunctioning?

Hello,

I've instantiated the Intel TSE IP Core in my design, testing on the Intel Arria 10 GX Development Kit board. From what I can tell it appears to be functioning: data can be sent and received, and the partner on the other side of the link shows auto-negotiation success and link up.

However, I'm getting weird behavior from the IP core's LEDs. After an Ethernet cable is unplugged the led_an (auto-negotiation success) and led_link/led_panel_link (link up) remain illuminated. led_crs (activity detect) works as you'd expect. Neither of the error LEDs are illuminated and I see no other hint of a problem.

If I unplug the cable, led_an and led_panel_link briefly turn off, but almost immediately re-illuminate even if the cable remains unplugged. led_link stays on no matter what.

Any clues as to what might be happening here? What information can I provide to help? Attached is an image of the cable unplug event. I'm stumped.

I'm setting the following registers, in this order, and confirmed they were set by reading them back.

Address <- Value

0x03 <- 0x04030201 // Mac upper

0x04 <- 0x00000605 // MAC lower

0x92 <- 0x00000D40 // Link timer lower

0x93 <- 0x00000003 // Link timer upper

0x80 <- 0x00009141 // PCS reset

0x02 <- 0x0000023B // TSE Control (TX_ENA, RX_ENA, ETH_SPEED, PROMIS_ENA, PAD_ENA, TX_ADDR_INS)