PROCESSOR-SDK-AM437X: PHY MDI/MDI-X function

Marcio Borges

Expert 1950 points

Hello,

I have questions related to EMAC / PHY and the MDI/MDI-X of the Ethernet transceiver.

From the PHY control state machine point of view what changes when the auto MDI/MDI-X is enabled?

If the auto MDI/MDI-X is enabled and the PHY state machine thinks it is disabled, could it cause connection/disconnection issues? Could it assume a disconnection to fast? Could it cause reception/transmission errors like crc and alignment?

Thanks in advance for your response.

Marcio.

over 3 years ago

0 Ashwani Goel over 3 years ago

TI__Mastermind 27690 points

Hi,

Thanks for your query.

Can you please explain your use case in more details ?

Which PHY you are using ?

PSDK version you are working on ?

you are using enet or emac based development ?

Best Regards

Ashwani

0 Marcio Borges over 3 years ago in reply to Ashwani Goel

Expert 1950 points

Hello Ashwani

My questions does not refer to an specific SDK, but to the AM437x and the KSZ9031 (Microchip) used in the evaluation board.

KSZ9031 has an auto MDI/MDI-X functionality.

I am trying to understand if the cpu EMAC module needs to be aware of the MDI/MDI-X configuration or it is transparent and if an error on enabling/disabling the auto MDI/MDI-X functionality could cause an issue, like disconnection, reception/transmission errors.

Best regards,

Marcio.

0 Ashwani Goel over 3 years ago in reply to Marcio Borges

TI__Mastermind 27690 points

Okay.

I will check and update you soon.

Best Regards

Ashwani

0 Ashwani Goel over 3 years ago

TI__Mastermind 27690 points

Marcio Borges said:
From the PHY control state machine point of view what changes when the auto MDI/MDI-X is enabled?

Our driver layer is not considering enable / disable. It assume PHY to detect this change and update to driver.

Best Regards

Ashwani

0 Ashwani Goel over 3 years ago in reply to Marcio Borges

TI__Mastermind 27690 points

Marcio Borges said:
I am trying to understand if the cpu EMAC module

Which specific example you are referring here ?
It is CPSW or ICSS ?

Best Regards

Ashwani

0 Marcio Borges over 3 years ago in reply to Ashwani Goel

Expert 1950 points

Thanks Ashwani.

I am talking about the CPSW.

0 Ashwani Goel over 3 years ago in reply to Marcio Borges

TI__Mastermind 27690 points

Ashwani Goel said:
Which specific example you are referring here ?

0 Marcio Borges over 3 years ago in reply to Ashwani Goel

Expert 1950 points

Hello,

I am not referring to any specific example.

I am just trying to understand if the cpu EMAC module needs to be aware of the MDI/MDI-X configuration or it is transparent (it does not care).

The reason of my question is because we already found an error in the phy driver. It was enabling the auto MDI-X using a wrong and reserved register.

We are seing disconnection, crc and alignment errors. We don´t know whether it is software or hardware. And as TI does not supports the sdk (for Windows) any more, we are carrying on a code analysis on the drivers.

Regards,

0 Ashwani Goel over 3 years ago in reply to Marcio Borges

TI__Mastermind 27690 points

Hi Marcio,

Sorry to say, but I can only say that we no more supporting it. Please find related documents here.

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1067148/faq-what-resources-are-available-for-ti-rtos-based-or-baremetal-am335x-am437x-sw-development

Best Regards

Ashwani

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PROCESSOR-SDK-AM437X: PHY MDI/MDI-X function