[U-Boot-Users] PPC4xx enet crossover

[Stefan Roese <sr@denx.de>]

On Monday 03 March 2008, Mike Nuss wrote:
> I'm using a PPC440EPx with a Marvell PHY (same as on Sequoia). If I connect
> to a PC with a crossover Ethernet cable, U-Boot sees a link but the PC does
> not. The PC (running Linux) reports "Autonegotiation failed (remote fault)"
> and ethtool reports no link.

Did you really try to communicate with the PC in this situation? Please note 
that the PHY is only initialized upon ethernet usage. So if you just turn on 
the Sequoia and stop on the U-Boot prompt, no real PHY configuration will 
happen.

> However if I let the PowerPC boot up into Linux, all of a sudden the PC
> sees link and pings start working. In fact, it works in Linux with a
> standard Ethernet cable, too (gigabit ports should be autosensing).

Understood. You should not need a crossover cable, since the PHY supports 
automatic MDI/MDIX crossover at all speeds of operation.

Best regards,
Stefan

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