AMCC 440EP phy detection

Eddie Dawydiuk eddie at
Wed Apr 8 04:20:00 EST 2009


> Are you able to ping in u-boot? Sounded like you were only pinging in 
> linux.

We are not using u-boot, we've written a custom bootloader. I see there are a 
few debugging flags in the emac driver I can enable, I'll do that next to look 
into the problem further. Thanks for the response.

> I would try the mii command in uboot. It seems like it detected the 
> phys. Try enable the
> loopbacks at the different stages to see if the traffic is returning. 
> This excerise is
> much easier in uboot than linux.
> Feng Kan
> AMCC Software
> Eddie Dawydiuk wrote:
>> Hello,
>> I'm working on a board based on the Yosemite AMCC 440EP eval board. 
>> I'm having some difficulty getting both network interfaces working. 
>> The first problem I found is the ibm_newemac driver was detecting the 
>> two phys at address 0 and 1 where we have them wired for addresses 1 
>> and 3. As a result I hardcoded the phy-address in the dts file. I then 
>> found I was able to receive and send data on eth1(phy-address 3) 
>> without incident. Although I found eth0 can receive data but I see no 
>> packets being transmitted(using a packet sniffer) and I see no 
>> indication from a software standpoint of any transmit failures. We are 
>> using Micrel KSZ8041FTL phys(RMII mode) where the Yosemite board used 
>> Micrel KS8721BL phys.  I've reviewed the schematic and it appears both 
>> phys are connected identically and I've seen this same failure on 
>> multiple boards. I thought the fact that the driver detected a phy at 
>> address 0 might be a clue, but I can't make much of the clue. So I 
>> thought I'd post this info in the hopes someone else might have run 
>> into a similar problem or have a suggestion.

Best Regards,
  Eddie Dawydiuk, Technologic Systems | voice:  (480) 837-5200
  16525 East Laser Drive 	     | fax:    (480) 837-5300
  Fountain Hills, AZ 85268            | web:

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