From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754096AbbF0BSd (ORCPT ); Fri, 26 Jun 2015 21:18:33 -0400 Received: from mail-ie0-f169.google.com ([209.85.223.169]:35895 "EHLO mail-ie0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755290AbbF0BQ3 (ORCPT ); Fri, 26 Jun 2015 21:16:29 -0400 MIME-Version: 1.0 In-Reply-To: <1435362871.26815.24.camel@kernel.crashing.org> References: <1434751712-24333-1-git-send-email-mcgrof@do-not-panic.com> <1435189081.3790.24.camel@kernel.crashing.org> <4985EFDD773FCB459EF7915D2A3621ADC02F10@nice.asicdesigners.com> <6806026.xb91q6Ad7G@wuerfel> <4985EFDD773FCB459EF7915D2A3621ADC031F8@nice.asicdesigners.com> <1435272718.3822.7.camel@kernel.crashing.org> <20150626193158.GJ3005@wotan.suse.de> <1435356258.26815.13.camel@kernel.crashing.org> <1435362871.26815.24.camel@kernel.crashing.org> From: "Luis R. Rodriguez" Date: Fri, 26 Jun 2015 18:16:08 -0700 X-Google-Sender-Auth: BA8P-BHct71YQhAt-1fPsPGoCUk Message-ID: Subject: Re: [Xen-devel] [PATCH v7 5/9] PCI: Add pci_iomap_wc() variants To: Benjamin Herrenschmidt , Russell King , Stefano Stabellini Cc: linux-fbdev , "Michael S. Tsirkin" , "linux-pci@vger.kernel.org" , Dave Hansen , Jan Beulich , =?UTF-8?B?VmlsbGUgU3lyasOkbMOk?= , "xen-devel@lists.xensource.com" , Arnd Bergmann , Tomi Valkeinen , Daniel Vetter , Dave Airlie , Ingo Molnar , Jean-Christophe Plagniol-Villard , Casey Leedom , Antonino Daplas , Suresh Siddha , Stefan Bader , Bjorn Helgaas , Thomas Gleixner , Juergen Gross , Toshi Kani , "linux-kernel@vger.kernel.org" , Andy Lutomirski , David Vrabel , "venkatesh.pallipadi@intel.com" , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 26, 2015 at 4:54 PM, Benjamin Herrenschmidt wrote: > On Fri, 2015-06-26 at 15:41 -0700, Luis R. Rodriguez wrote: > >> > It wasn't nullified for the main user at the time, the fb. And I >> > mentioned an IB adapter or two for which the code had been hand >> tuned. >> >> This still means there could be some affected drivers when used on >> powerpc, no? > > Yes. In fact what about things like ARM who also have barriers in their > writel() ? Won't they also break WC ? Not sure if they have that write-combine notion on their CPUs / interconnects. Russel, Stefano, does ARM have write-combining ? Luis From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Luis R. Rodriguez" Date: Sat, 27 Jun 2015 01:16:08 +0000 Subject: Re: [Xen-devel] [PATCH v7 5/9] PCI: Add pci_iomap_wc() variants Message-Id: List-Id: References: <1434751712-24333-1-git-send-email-mcgrof@do-not-panic.com> <1435189081.3790.24.camel@kernel.crashing.org> <4985EFDD773FCB459EF7915D2A3621ADC02F10@nice.asicdesigners.com> <6806026.xb91q6Ad7G@wuerfel> <4985EFDD773FCB459EF7915D2A3621ADC031F8@nice.asicdesigners.com> <1435272718.3822.7.camel@kernel.crashing.org> <20150626193158.GJ3005@wotan.suse.de> <1435356258.26815.13.camel@kernel.crashing.org> <1435362871.26815.24.camel@kernel.crashing.org> In-Reply-To: <1435362871.26815.24.camel@kernel.crashing.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Benjamin Herrenschmidt , Russell King , Stefano Stabellini Cc: linux-fbdev , "Michael S. Tsirkin" , "linux-pci@vger.kernel.org" , Dave Hansen , Jan Beulich , =?UTF-8?B?VmlsbGUgU3lyasOkbMOk?= , "xen-devel@lists.xensource.com" , Arnd Bergmann , Tomi Valkeinen , Daniel Vetter , Dave Airlie , Ingo Molnar , Jean-Christophe Plagniol-Villard , Casey Leedom , Antonino Daplas , Suresh Siddha , Stefan Bader , Bjorn Helgaas , Thomas Gleixner , Juergen Gross , Toshi Kani , "linux-kernel@vger.kernel.org" , Andy Lutomirski , David Vrabel , "venkatesh.pallipadi@intel.com" , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= On Fri, Jun 26, 2015 at 4:54 PM, Benjamin Herrenschmidt wrote: > On Fri, 2015-06-26 at 15:41 -0700, Luis R. Rodriguez wrote: > >> > It wasn't nullified for the main user at the time, the fb. And I >> > mentioned an IB adapter or two for which the code had been hand >> tuned. >> >> This still means there could be some affected drivers when used on >> powerpc, no? > > Yes. In fact what about things like ARM who also have barriers in their > writel() ? Won't they also break WC ? Not sure if they have that write-combine notion on their CPUs / interconnects. Russel, Stefano, does ARM have write-combining ? Luis From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Luis R. Rodriguez" Subject: Re: [PATCH v7 5/9] PCI: Add pci_iomap_wc() variants Date: Fri, 26 Jun 2015 18:16:08 -0700 Message-ID: References: <1434751712-24333-1-git-send-email-mcgrof@do-not-panic.com> <1435189081.3790.24.camel@kernel.crashing.org> <4985EFDD773FCB459EF7915D2A3621ADC02F10@nice.asicdesigners.com> <6806026.xb91q6Ad7G@wuerfel> <4985EFDD773FCB459EF7915D2A3621ADC031F8@nice.asicdesigners.com> <1435272718.3822.7.camel@kernel.crashing.org> <20150626193158.GJ3005@wotan.suse.de> <1435356258.26815.13.camel@kernel.crashing.org> <1435362871.26815.24.camel@kernel.crashing.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1435362871.26815.24.camel@kernel.crashing.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Benjamin Herrenschmidt , Russell King , Stefano Stabellini Cc: linux-fbdev , "Michael S. Tsirkin" , "linux-pci@vger.kernel.org" , Dave Hansen , Jan Beulich , =?UTF-8?B?VmlsbGUgU3lyasOkbMOk?= , "xen-devel@lists.xensource.com" , Arnd Bergmann , Tomi Valkeinen , Suresh Siddha , Dave Airlie , Ingo Molnar , Jean-Christophe Plagniol-Villard , Casey Leedom , Antonino Daplas , Stefan Bader , Daniel Vetter , Bjorn Helgaas , Thomas Gleixner , Juergen Gross , Toshi Kani , linux-kerne List-Id: xen-devel@lists.xenproject.org On Fri, Jun 26, 2015 at 4:54 PM, Benjamin Herrenschmidt wrote: > On Fri, 2015-06-26 at 15:41 -0700, Luis R. Rodriguez wrote: > >> > It wasn't nullified for the main user at the time, the fb. And I >> > mentioned an IB adapter or two for which the code had been hand >> tuned. >> >> This still means there could be some affected drivers when used on >> powerpc, no? > > Yes. In fact what about things like ARM who also have barriers in their > writel() ? Won't they also break WC ? Not sure if they have that write-combine notion on their CPUs / interconnects. Russel, Stefano, does ARM have write-combining ? Luis