Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266397AbTGEQno (ORCPT ); Sat, 5 Jul 2003 12:43:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266400AbTGEQno (ORCPT ); Sat, 5 Jul 2003 12:43:44 -0400 Received: from 66-75-253-176.san.rr.com ([66.75.253.176]:640 "EHLO mackman.net") by vger.kernel.org with ESMTP id S266397AbTGEQnn (ORCPT ); Sat, 5 Jul 2003 12:43:43 -0400 Date: Sat, 5 Jul 2003 09:58:06 -0700 (PDT) From: Ryan Mack X-X-Sender: rmack@mackman.net To: Markus Plail cc: linux-kernel@vger.kernel.org Subject: Re: 2.4.21 ServerWorks DMA Bugs In-Reply-To: <87fzllh21i.fsf@gitteundmarkus.de> Message-ID: References: <87fzllh21i.fsf@gitteundmarkus.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1540 Lines: 33 That at least explains the lack of DMA, but why does non-DMA IO result in such significant clock skew? Also, does anybody know what the status of the failure to recognize higher UDMA modes on the CSB5 chipset? Is there a working patch out there? Thanks again, Ryan On Sat, 5 Jul 2003, Markus Plail wrote: > On Fri, 4 Jul 2003, Ryan Mack wrote: > > > I've real the other threads but nothing touches on my specific issue. > > I have a dual P4 Xeon Dell PowerEdge 1600SC with a Fusion MPT SCSI > > controller and a ServerWorks CSB5 IDE chipset. All the HDs are on the > > SCSI bus, and only my CD reader and my DVD writer are on the IDE bus > > (one on each channel). Hyperthreading is enabled (4 logical > > processors). I am using GCC 3.2.2. > > > > The CD readers is the blacklisted 'SAMSUNG CD-ROM SC-148C' and I never > > use it so I can remove it if needed. The DVD writer is a 'SONY DVD RW > > DRU-500A'. Both are going through the ide-scsi driver. Whenever I > > read/write CDs in the DVD writer, I get very high system load (50% on > > one CPU), even though DMA seems to be enabled. > > If you are writing CDs with unusual block sizes (audio CDs, (S)VCDs, > RAW mode -> blocksize != 2048) you won't get DMA with ide-scsi, no > matter what you do. It's simply not supported. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/