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 PROCESSOR-SDK-J784S4: Not able to establish communication in BCM54810 Phy in LRE (Broadreach mode)

Swedha Raja's profile image
Swedha Raja posted Mar 24, 2025 10:17 AM

Hey hi,
I am Swedha, working on the custom J784S4 board, having broadcom phy (BCM54810) with RJ45 port. In IEEE mode the broadcom phy working is fine at 1000Mbps and 100Mbps.

But I want to make the communication works at LRE mode to achieve lond distance data transmission.
I am using the broadcom.c driver present in the linux sdk. I have tried with below change and it is not working.

I have by adding the new broadcom changes from the git too - linux/drivers/net/phy/broadcom.c at master · torvalds/linux

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It is not working.

I don't know what and all driver modifications I need to do for the phy and mac side for the LRE mode. And I am using twisted pair cables only.

 Is there any connection difference with Link partner b/w IEEE vs LRE modes?

 Any special handling needed from MAC side or not?

I am not sure, which register will tell whether we are using LRE/IEEE mode from the datasheet.

Kindly please help me in getting the communication work in LRE mode for broadcom phy. And let me know what and all changes needed to be done from the driver side for both mac and phy.

Awaiting for your reply.

Thanks in advance,
Swedha R

Jason McClellan's profile image
Community Manager Jason McClellan

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