I have a problem with ethernet link. During uboot, ethernet is working fine but when linux kernel starts booting, ethernet link starts going Down and Up. It takes random time until link is activated again. Then everything works fine until the module is turned off.
Kernel version - Linux version 4.14.170-5.0.0-devel
U-boot version - U-Boot 2019.07-5.0.0-devel
Here is a kernel boot log regarding fec:
[ 0.000000] Kernel command line: enable_wait_mode=off vmalloc=400M root=PARTUUID=d8f61057-02 ro rootfstype=ext4 rootwait fec_mac=00:14:2d:a3:07:6e consoleblank=0 no_console_suspend=1
[ 2.018354] fec 2188000.ethernet: 2188000.ethernet supply phy not found, using dummy regulator
[ 2.043753] libphy: fec_enet_mii_bus: probed
[ 2.049586] fec 2188000.ethernet eth0: registered PHC device 0
[ 10.235370] fec 2188000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
[ 10.263425] fec 2188000.ethernet eth0: Link is Down
[ 12.700608] fec 2188000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
[ 12.723248] fec 2188000.ethernet eth0: Link is Down
[ 15.433954] fec 2188000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
[ 15.464472] fec 2188000.ethernet eth0: Link is Down
[ 18.176805] fec 2188000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
[ 18.192986] fec 2188000.ethernet eth0: Link is Down
[ 20.706477] fec 2188000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
[ 20.721887] fec 2188000.ethernet eth0: Link is Down
[ 23.425438] fec 2188000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
[ 23.442989] fec 2188000.ethernet eth0: Link is Down
... the same repeats until ...
[ 339.663868] fec 2188000.ethernet eth0: Link is Down
[ 342.145725] fec 2188000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
[ 342.165060] fec 2188000.ethernet eth0: Link is Down
[ 344.596871] fec 2188000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx