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I am using 3.4.43 linux kernel with Fedora 14 and 82574L Intel NIC with two ports, one of the ports has hardware timestamping support for PTP. And I have installed the latest 2.3.2-NAPI e1000e driver. The port which does not have hardware timestamp support comes up fine but the other port shows as "Link detected: no" in "ethtool -i eth3", but I see rx interrupts continue to increase periodically in /proc/interrupts. This link is connected to a Gigabit switch and the other side of the link always shows as connected. This is the output of ethtool for this port which has timestamping support.

Settings for eth3:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full 
                                100baseT/Half 100baseT/Full 
        Supports auto-negotiation: Yes
        Advertised link modes:  10baseT/Half 10baseT/Full 
                                100baseT/Half 100baseT/Full 
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Speed: Unknown!
        Duplex: Unknown! (255)
        Port: Twisted Pair
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: on
        MDI-X: Unknown
        Supports Wake-on: pumbg
        Wake-on: g
        Current message level: 0x00000007 (7)
                               drv probe link
        Link detected: no

I have even tried swapping cables for these two ports, but no help. Could someone suggest what else to try here ? I have googled a lot but did not find any satisfactory answer. The other link works because thats configured as management interface and I am able to do ssh through that. The other weird thing about this non-working interface is ifconfig says that the link is up:

eth3      Link encap:Ethernet  HWaddr 00:25:90:52:6F:69  
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
          Interrupt:16 Memory:fbae0000-fbb00000 

I have re-compiled the kernel with timestamping PTP support required by this driver.

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