DP83869HM: Issue while accessing the PHY

ranjini r

Part Number: DP83869HM

Hi,

We faced an issue while testing the Ethernet interface in our board. We have two PHY each with different mode & address. I've attached the schematic for reference. We are using Zynq Ultrascale+ MPSoC FPGA.

We were able to access and ping the first PHY(RGMII to Copper mode). But not able to access the second PHY. The address of the second PHY was 0001 which Later was changed the address to 0011. RX_D0 was made MODE3 & RX_D1 in MODE0, we were able to access the PHY. The address we saw on the prompt was 05 07 which is not matching with the address hard-wired(in schematic)

The register values of 2nd PHY is as follows

ZynqMP> mii read 7 0x6E
0000
ZynqMP> mii read 7 0x1DF
0000

Can you look into this and say what is the reason for this? Are we missing anything?

Thanks & Regards,

Ranjini.R

ETH_PHY.pdf

over 3 years ago

0 Alon Kopelman over 3 years ago

TI__Expert 3727 points

Hi Ranjini,

If you are reading 0000 on both registers, it is likely you are not communicating properly with the PHY.

Are you able to get link-up, and send packets?

You are saying one of the PHYs is setup correctly and working and the other one wont set the address properly?

Best,

Alon

0 ranjini r over 3 years ago in reply to Alon Kopelman

Prodigy 150 points

Hi Alon,

Yes, the 1st PHY is working properly(ping from host PC) but the address shown is 05 while as per hardware it should be 0.

The other PHY wont show the proper address or functional mode properly.

ZynqMP> mii read 7 0x6E
0000
ZynqMP> mii read 7 0x1DF
0000

Thanks & Regards,

Ranjini.R

0 Alon Kopelman over 3 years ago in reply to ranjini r

TI__Expert 3727 points

Can you check that the PHY is alive?

Can you you link up and send packets?

Best,

Alon

0 ranjini r over 3 years ago in reply to Alon Kopelman

Prodigy 150 points

Link status is 0

0 Alon Kopelman over 3 years ago in reply to ranjini r

TI__Expert 3727 points

Hi Ranjini,

In order to help here, I will need more information, is the PHY turned on? (can you see clock signal at CLK_OUT pin?)

Are you running the same board for both?

Best,

Alon

0 ranjini r over 3 years ago in reply to Alon Kopelman

Prodigy 150 points

Hi Alon,

can you see clock signal at CLK_OUT pin?- The clock seems to be fine.

Are you running the same board for both? - yes

Thanks & Regards,

Ranjini

0 Alon Kopelman over 3 years ago in reply to ranjini r

TI__Expert 3727 points

Ranjini,

I want to make sure I understand correctly.

You have two PHY's, one works perfectly, links up perfectly, sends/receives packets, and you are able to read/write registers.

The second one, turns ON, but doesn't link up, and doesn't show register values when attempting to read.

When you set the second PHY address to be the first PHY (Trade places between the two PHY's), does the behavior stay or disappear?

Does it move with the PHY or does it move with the board.

Please do your best to provide in depth detail so I am able to best assist you.

Best,

Alon

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DP83869HM: Issue while accessing the PHY