[U-Boot] [PATCH 3/7] fec_imx27: driver for FEC Ethernet controller on i.MX27

[Bill Cook]

> -----Original Message-----
> From: Eric Lammerts [mailto:u-boot at lists.lammerts.org]
> Sent: Monday, June 15, 2009 3:59 PM
> To: Johan
> Cc: u-boot at lists.denx.de; Ilya Yanok
> Subject: Re: [U-Boot] [PATCH 3/7] fec_imx27: driver for FEC ethernet
> controller on i.MX27
>
>
> On 06/15/09 10:01, Johan wrote:
> > I have trouble using your patch together with our LogicPD iMX27
> > Litekit. Seems like the FEC driver does not work well. Here is some
> > output from when I try to load files with tftp
>
> <snip>
> > Loading: #####T #####################T #########################T
> ############T#
> >          #########################T ########################################
> >          ##T ####################################T #########T T #########
> > Retry count exceeded; starting again
>
> <snip>
> > I have downloaded the imx27lite head from the u-boot testing branch. I
> > have also tried to patch the u-boot-2009.06-rc3 branch with your
> > patches, but it does not seem to be any different. Do you have any
> > ideas what might be wrong?
>
> Did you have working ethernet before (with a different bootloader or in
> Linux)? Do you have the breakout board installed? I have the same board
> (but maybe an older revision; about a year old) and with the breakout
> board mounted my ethernet would behave the same way as yours. They routed
> the MII signals all the way to the headers on the breakout board, and
> that causes signal integrity problems. It could be that they fixed it on
> later revisions though (not sure).
>
> I'm using u-boot-v2, so I don't know anything about the u-boot fec driver.
>
> Eric
>
I'm trying to debug ethernet problems on a custom iMX27 board with
same LAN chip as the logicPD liteKit. I don't claim to be an expert,
but it seems that in the fec driver posted by Ilya, the phy address
for MII access is hard coded to a 0, whereas on the board it defaults
to 0x1f. When I turned on DEBUG in fec_imx27.c, the MII reads always
return all 1's. The phy works, but maybe by good fortune, not intent.

Bill Cook
cook at isgchips.com
Imaging Solutions Group Inc;
http://www.isgcameras.com