From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937350AbXGMXM6 (ORCPT ); Fri, 13 Jul 2007 19:12:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760419AbXGMXMr (ORCPT ); Fri, 13 Jul 2007 19:12:47 -0400 Received: from gate.crashing.org ([63.228.1.57]:50730 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758647AbXGMXMr (ORCPT ); Fri, 13 Jul 2007 19:12:47 -0400 Subject: Re: [patch 5/6] ps3: BD/DVD/CD-ROM Storage Driver From: Benjamin Herrenschmidt To: Arnd Bergmann Cc: linuxppc-dev@ozlabs.org, James Bottomley , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Alessandro Rubini , Paul Mackerras , Jens Axboe , Geert Uytterhoeven In-Reply-To: <200707131619.54898.arnd@arndb.de> References: <20070704132212.726923000@pademelon.sonytel.be> <1184335333.3402.20.camel@localhost.localdomain> <200707131619.54898.arnd@arndb.de> Content-Type: text/plain Date: Sat, 14 Jul 2007 09:12:08 +1000 Message-Id: <1184368328.6059.271.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.10.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2007-07-13 at 16:19 +0200, Arnd Bergmann wrote: > I'm pretty sure that no ppc64 machine needs alias resolution in the kernel, > although some are VIPT. Last time we discussed this, Segher explained it > to me, but I don't remember which way Cell does it. IIRC, it automatically > flushes cache lines that are accessed through aliases. Ah yes, I remember reading about this automatic flushing thing. I don't know how the caches actually work on most of our PPC's, but the fact is, we don't have aliasing issues, so I can safely ignore it for a bit longer :-) There are some aliasing issues with the instruction cache specifically on some 4xx models but that's irrelevant to this discussion (and I think we handle them elsewhere anyway). Ben.