From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bh-25.webhostbox.net ([208.91.199.152]:45989 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757176AbbGGPBu (ORCPT ); Tue, 7 Jul 2015 11:01:50 -0400 Message-ID: <559BE9D9.4050407@roeck-us.net> Date: Tue, 07 Jul 2015 08:01:45 -0700 From: Guenter Roeck MIME-Version: 1.0 To: Lorenzo Pieralisi CC: Bjorn Helgaas , "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "suravee.suthikulpanit@amd.com" , Will Deacon Subject: Re: [PATCH] PCI: Only enable IO window if supported References: <1432342336-25832-1-git-send-email-linux@roeck-us.net> <20150527210447.GY32152@google.com> <20150528022332.GA23724@roeck-us.net> <20150528124112.GJ10210@google.com> <20150618180103.GA23809@roeck-us.net> <20150619162413.GA21533@red-moon> <20150707144019.GH4379@red-moon> In-Reply-To: <20150707144019.GH4379@red-moon> Content-Type: text/plain; charset=windows-1252; format=flowed Sender: linux-pci-owner@vger.kernel.org List-ID: Hi Lorenzo, On 07/07/2015 07:40 AM, Lorenzo Pieralisi wrote: > On Fri, Jun 19, 2015 at 05:24:13PM +0100, Lorenzo Pieralisi wrote: >> Hi Guenter, >> >> On Thu, Jun 18, 2015 at 07:01:03PM +0100, Guenter Roeck wrote: >>> On Thu, May 28, 2015 at 07:41:12AM -0500, Bjorn Helgaas wrote: >>>> >>>>>> I'd like res->flags to reflect the capabilities of the hardware, not >>>>>> whether the window is currently enabled. >>>>>> >>>>> Flag bits seem to be all taken. Could we use IORESOURCE_DISABLED for that >>>>> purpose, or could that cause conflicts elsewhere ? >>>> >>>> Yes, I think IORESOURCE_DISABLED would be appropriate for any I/O windows >>>> below a host bridge that doesn't support I/O space. >>>> >>> I integrated Lorenzo's patch and tried to get this working. >> >> Thanks. How do you want to proceed with this ? Are you taking my patch >> and post it along with your updated series ? We need to extend test >> coverage to platforms we could not test on, as you know my series >> affects all archs but SPARC (I mean it should *not* affect them, this >> has to be tested though, I do not have the HW needed, your coverage >> for x86 and PowerPC is great but I do not think it can be deemed >> sufficient). >> >> Please let me know, thanks ! > > Any comment on this ? I will have to remove the bridge resource claiming > from my patch according to Ben's concerns for PowerPC, which requires > a v3. > > How do you want me to go on with this ? > Can you send your v3 ? I didn't submit my latest version because I recalled Ben's objections, and I never got around asking you if you plan to send a new version of your patch. I had to drop the idea of using IORESOURCE_DISABLED; pretty much all kernel code uses the "!flags" test to identify unused resources. I tried to change that, but just could not get it to work. I ended up introducing a new bus flag instead, PCI_BUS_FLAGS_NO_IO, which works quite nicely since it propagates to child buses. Thanks, Guenter