Board: am1808 EVM
Kernel: prebuilt uImage-am180x-evm.bin (SDK: ti-sdk-am180x-evm-05.03.02.00-Linux-x86-Install)
Rootfs: extracted base-rootfs-am180x-evm.tar.gz (Seems not relevant. It's from the SDK, too.)
I use AM1808 EVM and encounter a problem that the ethernet PHY is easily dead (about 50%) if I "ifconfig eth0 up" without plugging in ethernet cable.
Reproduce procedure:
1. Power on WITHOUT plugging ethernet cable (MUST)
2. Boot into linux shell
> ifconfig eth0 up
davinci_mdio davinci_mdio.0: resetting idled controller
net eth0: attached PHY driver [SMSC LAN8710/LAN8720] (mii_bus:phy_addr=0:00, id=7c0f1)
(I traced and found the behavior is: "up" -> reset emac -> reset mdio)
3. Plug in ethernet cable after 5 sec
--> Problem: Ethernet port LED isn't blinking anymore! Of course, PHY can't link up. Looks like the PHY is dead! Replugging or "ifconfig down and up" can't help PHY recover.
What I can do is reboot the system and let PHY recover.
Q1: Is the PHY module inside am1808? Or it resides on the board? Should it be reset after MDIO reset?
Q2: Is the PHY dead?
I suppose this usage is very common. Please help us clarify and solve the problem.
