Hi All,
I have interesting issues on the custom DM8148 board. Basically, the custom board has 1 PHY(KSZ9021GN) and 1 switch(Marvell 88e6122) for interface of other processors and video source. The GMII is used for the interface with PHY.
The issues are on each PHY/switch interface. First one occurs on Gigabit KSZ9021 PHY chip. It only works with 100Mbps and doesn't work with Gbps network, even though the Gigabit link is established. The dual MAC patch has been applied and it is first ethernet device (eth0). Also interesting thing is that only 25MHz clock is measured on GMTCLK and MTCLK and they are provided by DM8148.
The other is NO CLK (GMTCLK and MTCLK) present, even though Marvell switch gives 125MHZ clock to DM8148. I have checked out Ethernet Mac Sliver (CPGMAC_SL), GMII_EN and pinmux registers and they look fine. When a cable is plugged in, both side PHY - DM8148 EVM and built-in PHY on Marvell 88e6122 detect each other. The ethernet interfaces on the custom board look like below.
DM8148 -+------ EMAC (0) ---- KSZ9021 PHY : working on 100Mbps only and it detects peer PHY for 1000/100Mbps
|
+------- Marvell 88E6122 built-in PHY : not working at all and it detects peer PHY for 1000/100Mbps
Any suggestion or idea ?
Best Regards,
SK