Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760185AbXKAJm2 (ORCPT ); Thu, 1 Nov 2007 05:42:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755192AbXKAJmT (ORCPT ); Thu, 1 Nov 2007 05:42:19 -0400 Received: from outpipe-village-512-1.bc.nu ([81.2.110.250]:44029 "EHLO the-village.bc.nu" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1753598AbXKAJmS (ORCPT ); Thu, 1 Nov 2007 05:42:18 -0400 Date: Thu, 1 Nov 2007 09:43:44 +0000 From: Alan Cox To: Jeff Garzik Cc: linux-ide@vger.kernel.org, LKML Subject: Re: [PATCH] libata ATAPI transfer size cleanups Message-ID: <20071101094344.6eb9d8bc@the-village.bc.nu> In-Reply-To: <20071101090733.GA9258@havoc.gtf.org> References: <20071101090733.GA9258@havoc.gtf.org> X-Mailer: Claws Mail 2.10.0 (GTK+ 2.10.14; i386-redhat-linux-gnu) Organization: Red Hat UK Cyf., Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, Y Deyrnas Gyfunol. Cofrestrwyd yng Nghymru a Lloegr o'r rhif cofrestru 3798903 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1015 Lines: 24 On Thu, 1 Nov 2007 05:07:33 -0400 Jeff Garzik wrote: > > This is purely for comment and testing, not for merging (yet?). > > A common recipe in several vendor drivers (either GPL'd, or I have NDA'd > access to use them as a documentation-like reference) for ATAPI was > slightly different from ours. This recipe can be found in > atapi_tf_xfer_size(), and it's slightly different from Alan's. Looks mostly good. Might cause breakage on one or two controllers by setting lbam/lbah to 0 for DMA but we can test that and find out. Note however - the scheme in use now has been tested for over ten years in drivers/ide. The scheme below has not... Having an ata_tf_xfer_size method is definitely a good idea whatever methods we eventually decide on. - 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/