From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750979AbWGFWjg (ORCPT ); Thu, 6 Jul 2006 18:39:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750976AbWGFWjg (ORCPT ); Thu, 6 Jul 2006 18:39:36 -0400 Received: from gate.crashing.org ([63.228.1.57]:57318 "EHLO gate.crashing.org") by vger.kernel.org with ESMTP id S1750831AbWGFWjg (ORCPT ); Thu, 6 Jul 2006 18:39:36 -0400 Subject: Re: [PATCH 38 of 39] IB/ipath - More changes to support InfiniPath on PowerPC 970 systems From: Benjamin Herrenschmidt To: "Bryan O'Sullivan" Cc: akpm@osdl.org, rdreier@cisco.com, mst@mellanox.co.il, openib-general@openib.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org In-Reply-To: References: Content-Type: text/plain Date: Fri, 07 Jul 2006 08:37:01 +1000 Message-Id: <1152225421.9862.12.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.6.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > +#if defined(__powerpc__) > + /* There isn't a generic way to specify writethrough mappings */ > + pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE; > + pgprot_val(vma->vm_page_prot) |= _PAGE_WRITETHRU; > + pgprot_val(vma->vm_page_prot) &= ~_PAGE_GUARDED; > +#endif I don't see any case where having both NO_CACHE and WRITE_THRU can be legal... It's one or the other. > +/** > + * ipath_unordered_wc - indicate whether write combining is ordered > + * > + * PowerPC systems (at least those in the 970 processor family) > + * write partially filled store buffers in address order, but will write > + * completely filled store buffers in "random" order, and therefore must > + * have serialization for correctness with current InfiniPath chips. > + * > + */ > +int ipath_unordered_wc(void) > +{ > + return 1; > +} How is the above providing any kind of serialisation ? Ben.