STM32MP157 Device Tree for Fixed Phy RGMII using RCC125 Clk

[Bkell.1]

Hi

We have a Custom Board based from MB1272 dev kit.

Our system needs to connect the RGMII to a Marvell Switch Chip where that Switch is Managed MDIO from a different MPU.

As such we need our STM32MP157 MPU to run in a fixed phy mode and use the RCC to be its 125Mhz clk.

Please see simplified drawing

I have looked at the https://wiki.st.com/stm32mpu/wiki/Ethernet_device_tree_configuration#RGMII_with_Crystal_on_PHY-2C_no_125Mhz_from_PHY

but still confused as to how to do this

We have tried a few DT settings but  no success, 

would really appreciate some help on this one

Thanks 

[PatrickF]

Hi,

trying to help, maybe share more details of what's going wrong. 
Any dmesg on the console to share ?

You should also define the 125MHz clock path in the DT.
https://wiki.st.com/stm32mpu/wiki/Clock_overview 

Regards,