From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: RX problem in ibm_newemac driver Date: Wed, 11 Mar 2009 07:50:01 +1100 Message-ID: <1236718202.7086.10.camel@pasglop> References: <49B6C4A2.8060302@embedded-sol.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: Felix Radensky Return-path: Received: from gate.crashing.org ([63.228.1.57]:59078 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752651AbZCJUuO (ORCPT ); Tue, 10 Mar 2009 16:50:14 -0400 In-Reply-To: <49B6C4A2.8060302@embedded-sol.com> Sender: netdev-owner@vger.kernel.org List-ID: On Tue, 2009-03-10 at 21:50 +0200, Felix Radensky wrote: > Hi, > > I'm experiencing RX problem on custom board based on AMCC > 405EXr processor. Channel 0 of EMAC is connected to 10/100 > Micrel KSZ8041NL PHY in MII mode. Ethernet works fine in > u-boot (version 2009.01). In Linux (2.6.27) Ethernet works fine > as well if EMAC was initialized in u-boot. It is enough to send > ping from u-boot (even to non-existing host) to make things work > in linux. But if u-boot takes kernel and ramdisk images from flash > and does not initialize EMAC only TX side works in linux. You should CC linuxppc-dev where you are more likely to find people to help here. > I can see that TX counters are incremented when pinging from > EMAC side, but RX counters remain zero. RX error counter > in PHY is zero as well. I've enabled debugging in EMAC > driver and verified that RX EOB interrupt is not triggered. > FER register in RGMII bridge is properly configured for MII > mode on channel 0. I've tried to dump EMAC registers using > ethtool and got machine check exception. > > I don't know what else could be done to identify the source of > the problem. Any tips would be greatly appreciated. I don't have a 405EXr here, but it smells like the old reset problem when the link is down. Maybe we are missing code to force clocks on 405EXr when there's no link ? Ben.