From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp3.aruba.it (smtpd3.aruba.it [62.149.128.208]) by ozlabs.org (Postfix) with SMTP id 16059DDDF0 for ; Tue, 16 Jan 2007 20:37:20 +1100 (EST) Subject: Re: Ethernet fails on MPC5200 based target From: Andrea Galbusera To: Sylvain Munaut In-Reply-To: <45A4FDAF.8020909@246tNt.com> References: <1168439212.5271.70.camel@localhost.localdomain> <45A4FDAF.8020909@246tNt.com> Content-Type: text/plain Date: Tue, 16 Jan 2007 09:20:15 +0100 Message-Id: <1168935615.22089.31.camel@localhost.localdomain> Mime-Version: 1.0 Cc: linuxppc-embedded@ozlabs.org List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi Sylvain, some new elements in trying to solve my ethernet issue... On Wed, 2007-01-10 at 15:52 +0100, Sylvain Munaut wrote: > Maybe some things (like xlb pipelining, cache snooping, ...) is not properly > setup in you platform support code ? Following your suggestion, I started from here... Comparing the unaffected kernel (from DENX) with yours I tryed commenting out the following in mpc52xx_setup_cpu() : /* Disable XLB pipelining */ /* (cfr errate 292. We could do this only just before ATA PIO transaction and re-enable it after ...) */ out_be32(&xlb->config, in_be32(&xlb->config) | MPC52xx_XLB_CFG_PLDIS); In fact this gives much better results, but does not completely solve the problem. Network packets corruption seems to be gone, but, after massive pinging (about 1k ping packets) it comes back with about the same frequency as before the change. Not tested yet the impact of this change on ATA/IDE functionality/performance, but, if I'm not wrong, disabling the XLB pipelining was due to a hardware bug of the CPU (errata 292), which should be solved in 5200B, the version that I use. I can't figure out what is the impact of keeping XLB pipelining enabled on the eth behavior. I'm sharing this results in the hope someone have any other valuable suggestion Regards, -- Andrea