Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S270763AbTGPM5o (ORCPT ); Wed, 16 Jul 2003 08:57:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S270776AbTGPM5o (ORCPT ); Wed, 16 Jul 2003 08:57:44 -0400 Received: from pc2-cwma1-4-cust86.swan.cable.ntl.com ([213.105.254.86]:18121 "EHLO lxorguk.ukuu.org.uk") by vger.kernel.org with ESMTP id S270763AbTGPM5m (ORCPT ); Wed, 16 Jul 2003 08:57:42 -0400 Subject: Re: Trying to get DMA working with IDE alim15x3 controller From: Alan Cox To: Art Haas Cc: Bartlomiej Zolnierkiewicz , Linux Kernel Mailing List In-Reply-To: <20030715233202.GB17444@artsapartment.org> References: <20030715233202.GB17444@artsapartment.org> Content-Type: text/plain Content-Transfer-Encoding: 7bit Organization: Message-Id: <1058360981.6633.4.camel@dhcp22.swansea.linux.org.uk> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.2.2 (1.2.2-5) Date: 16 Jul 2003 14:09:49 +0100 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1154 Lines: 29 On Mer, 2003-07-16 at 00:32, Art Haas wrote: > I'd received mail from another person stating that the ALi DMA is broken > from many old chips, but that it is only the UDMA stuff that is broken, The older chips dont do UDMA. Then a lot of the next range of chips do UDMA but not 48bit command so you can end up in PIO mode. Possibly our logic for this needs tightening now we use lba28 commands whenever possible, so an LBA48 capable disk under LBA48 limit size is drivable entirely in LBA28 safely. > and the MW_DMA stuff works. Also the notes about the 2.6 transition > indicate ali15x3 and DMA don't always play nicely together. Still, > if the MW_DMA stuff works, some hdparm trickery like ... Simplex DMA needs some fixing for one. That should only bite you if you have a set up something like hda -> unused hdb -> unused hdc -> DISK hdd -> unused in which case we assign the DMA engine to hda/hdb! - 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/