AM335x RGMII to SWITCH connection

praveen verma

Other Parts Discussed in Thread: AM3359

Hi,

As mentioned in the switch datasheet, we are connecting am335x rgmii port to switch as follow:

Doubt: In one of thread I found that mac to mac connection is not supported. So will the above connection work? If yes, could you tell me what changes are required in u-boot and kernel; to support above connection

over 12 years ago

0 Biser Gatchev-XID over 12 years ago

TI__Guru**** 393215 points

What you have seen is correct. MAC to MAC connection is not supported on the AM335X.

0 praveen verma over 12 years ago in reply to Biser Gatchev-XID

Prodigy 60 points

Thanks for the reply,

Could you please elaborate why mac to mac is not supported on am335x. Is there any errata/document available for this?

0 Biser Gatchev-XID over 12 years ago in reply to praveen verma

TI__Guru**** 393215 points

there is no document about this. Here is an explanation from the factory team:

"The signal definitions are symmetrical, but the protocol is not symmetrical. Therefore, one device must operate as the Ethernet MAC and the other must operate as the Ethernet PHY. AM335x only supports the MAC function so the attached device would need to function as the PHY. For example, some of the 1Gbps Ethernet switches have one RGMII port that can be configured to emulate a PHY."

0 praveen verma over 12 years ago in reply to Biser Gatchev-XID

Prodigy 60 points

Hi Biser,

Our Switch provider says, "RGMII MAC can emulate as a PHY".

In that case, Can we directly use the existing CPSW driver?

Regards,

Praveen

0 Biser Gatchev-XID over 12 years ago in reply to praveen verma

TI__Guru**** 393215 points

Hi Praveen,

I'm sorry, I can't help much on software questions. I only work on hardware issues.

0 praveen verma over 12 years ago in reply to Biser Gatchev-XID

Prodigy 60 points

Hi,

Has anybody used switch in which "mac can emulate as a phy".

In that case will normal phy write/read will work?

regards,

Paveen

0 Eric Gross over 12 years ago in reply to Biser Gatchev-XID

Prodigy 10 points

Can the Sitara be connected to one of your DSP's like the 6455 via the RGMII interface?

0 peaves over 12 years ago in reply to Eric Gross

TI__Guru 62855 points

This would only work if RGMII of the attached device were able to operate in PHY mode. The AM335x MAC expects an RGMII PHY to be connected, not another MAC.

Regards,
Paul

0 huaihao guo over 11 years ago in reply to Biser Gatchev-XID

Prodigy 250 points

I have some question.

I am now working on raw Raw Ethernet Sockets Programming, I find in my application that i cannot receive MAC packet in which the destination MAC address is not my am3359's.

does it means i can only receive packet which destination MAC address is my am3359??

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AM335x RGMII to SWITCH connection