TDA4VM: Accessing external PHY via MDIO bus connected to CPSW9G internal switch from Linux

Sakthivelu Sambasivam

Prodigy 100 points

Part Number: TDA4VM

Hi,

I have a custom designed board where some 3rd party PHYs are interfaced to the MACports of cpsw9g - internal switch.

As I understand, CSW9G internal switch is managed by EthFW and it controls the MDIO bus too.

I have the PHY driver already integrated into Linux. Now, the question is :

1. For the EthFW to access the PHY, is it mandatory to have the PHY driver integrated into ENET_LLD?

2. Is MDIO bus accessible from Linux ? - can the PHY be accessed from Linux via MDIO bus?

over 4 years ago

0 Stanley Liu over 4 years ago

TI__Guru 50045 points

Hi,

1. TI CPSW9G EthFW can only run on R5 so the PHY driver has to on R5.

2. EthFW does support custom IOCTL to access MDIO bus from Remote core, like A72. However, you will have to add it as custom command in proxy. We don't have this implemented in SDK.

You can also refer to the below thread for similar question and answer.

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1004311/tda4vm-how-to-read-or-write-phy-register-data-of-cpsw-phys-within-linux

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/973948/compiler-tda4vm-how-to-read-or-write-phy-register-data-of-main_r5f_0_0-on-a72

Regards,
Stanley

Processors

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TDA4VM: Accessing external PHY via MDIO bus connected to CPSW9G internal switch from Linux