[U-Boot-Users] FEC problems on mpc852

[U-Boot-Users] FEC problems on mpc852

[Chris Simmonds]

Hi,

I am having some problems getting the FEC to work, perhaps someone on 
the list has seen something like it and can help me out?

The problem occurs in fec_send (in cpu/mpc8xx/fec.c): the 
BD_ENET_TX_READY bit is set but never cleared, indicating that the 
packet is ready to send but the hardware is not processing it. The 
receive side works fine: packets are received and processed as expected. 
So, I do not suspect the physical path to the outside world. Anybody any 
ideas what could cause this sort of behaviour? Any known problems with 
the 852T? What can I look at to find out what is going on? By the way, 
this is on u-boot 0.4.4.

Best regards,
Chris Simmonds

[U-Boot-Users] FEC problems on mpc852

[Wolfgang Denk]

Dear Chris,

in message <3F38F620.4060207@2net.co.uk> you wrote:
> 
> The problem occurs in fec_send (in cpu/mpc8xx/fec.c): the 
> BD_ENET_TX_READY bit is set but never cleared, indicating that the 
> packet is ready to send but the hardware is not processing it. The 
> receive side works fine: packets are received and processed as expected. 
> So, I do not suspect the physical path to the outside world. Anybody any 
> ideas what could cause this sort of behaviour? Any known problems with 
> the 852T? What can I look at to find out what is going on? By the way, 
> this is on u-boot 0.4.4.

Check the clock routing for your Tx side. Maybe there is no Tx  clock
so the bits don't get clocked out?

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
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