AR8031 on I.MX6 WORKS ONLY 10/100M AND LOSES PACKAGES WITH GIGA ROUTER OR SWITCH

[foxmaze]

Hello all,

I have designed a customer board with AR8031 PHY and I.MX6DL, and found the board only works with 10/100M stably, when connected to a GIGA-bit router or switch, the connection is very slow and many packages are lost.

Is there anyone with the same issue? Circuit of this portion is strictly following with the SABRESDP reference, only the RGMII signal traces are a little bit longer of up to 4000mils comparing the reference of  ~1700mils. Not sure this is the root cause. 125M clock is there and enhancing the VDDIO_REG of AR8031 to 2.5V behaves the same thing.

Can anyone help with this issue? Thanks.

Mling

[huangchudong7]

Hi foxmaze,

          I recently encountered the same problem with you, and now is no way of thinking, so I would like to ask you how to solve this problem?Thanks.

Huang

[foxmaze]

The issue is from freescale software, when downgrading to lower version kernel 3.0.35, the gbit ethernet works.

Not sure why freescale released the software version by careless test, those ones who want to run gbit ethernet on andriod 5.0 please take care.

[jimmychan · Accepted solution]

there is known erratum ERR004512 (ENET : 1 Gb Ethernet MAC (ENET) system limitation) described in

• Chip Errata for the i.MX 6Solo/6DualLite - Errata

    (REV 5) 

http://cache.nxp.com/files/32bit/doc/errata/IMX6SDLCE.pdf?fpsp=1&WT_TYPE=Errata&WT_VENDOR=FREESCALE&...

[foxmaze]

Hello Jimmy,

I know this errata but I don't think it describes what I concern. If the setup likes 10/100M router + Giga switch + i.mx6 board, the connection is also very slow or even lost, that is to say once there is a Giga device connects to the board, the connection will be effected.

I checked the FSL EVB board, distance among MAC,PHY and RJ45 are very short, I'm not sure if the layout really matters.