From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from kunk.qbjnet.com (ddsl1-28.ddsl.mr.net [137.192.135.28]) by ozlabs.org (Postfix) with SMTP id E8C3767A65 for ; Fri, 18 Mar 2005 13:55:35 +1100 (EST) Date: 18 Mar 2005 02:55:29 -0000 Message-ID: <20050318025529.553.qmail@kunk.qbjnet.com> From: linuxppcdev@qbjnet.com To: linuxppc-dev@ozlabs.org Subject: Re: DMA appears broken in 2.6.11 for Mac 7200 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Ben Said: > On Mon, 2005-03-14 at 03:51 +0000, linuxppcdev@qbjnet.com wrote: > > Just updated a couple of old Mac 7200 (601) boxen and ran into trouble with > > the ide driver and a promise PDC20267 card. > > > > The very same drives and card work fine on a 9500 but hang on a 7200. If > > I set the kernel arg ide=nodma I get in the dmesg: > > ide_setup: ide=nodma : Prevented DMA > > and the 7200 boots and runs fine. > > > > Another suspect, the mace ethernet driver (which also appears to use DMA) > > doesn't work on the 7200 with 2.6.11 but does with 2.4.28 and it works > > with 2.6.11 on the 9500. > > Interesting. Not sure what's up, though. Those old machines were known > to have bugs relative to cache coherency... also check wetehr we are > setting the cache line size properly in PCI devices. You can also try to > disable use of PCI memory write & invalidate command in all devices. Did some more testing on this. Built a 2.4.30-pre1 kernel from bk source. DMA works fine booting 2.4.30 I compared the dmesg and lspci and I see no differences in the cache line size. Is it possible that the ppc 601 kernel fixes aren't getting done properly in 2.6?? Bob