From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_2 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B0715C3F2CD for ; Fri, 28 Feb 2020 13:43:07 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6C901246AE for ; Fri, 28 Feb 2020 13:43:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6C901246AE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id 28630203F9; Fri, 28 Feb 2020 13:43:07 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 5pT07c7XVqVU; Fri, 28 Feb 2020 13:43:06 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by silver.osuosl.org (Postfix) with ESMTP id F04E020033; Fri, 28 Feb 2020 13:43:05 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id D84D2C1D84; Fri, 28 Feb 2020 13:43:05 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 6C629C0177 for ; Fri, 28 Feb 2020 13:43:04 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 685A586D9E for ; Fri, 28 Feb 2020 13:43:04 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id D_vCFf7aw3Lj for ; Fri, 28 Feb 2020 13:43:02 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by fraxinus.osuosl.org (Postfix) with ESMTP id 5EB2D86DD1 for ; Fri, 28 Feb 2020 13:43:02 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5A33A31B; Fri, 28 Feb 2020 05:43:01 -0800 (PST) Received: from donnerap.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7C8153F7B4; Fri, 28 Feb 2020 05:42:57 -0800 (PST) Date: Fri, 28 Feb 2020 13:42:54 +0000 From: Andre Przywara To: Will Deacon Subject: Re: [RFC PATCH 06/11] iommu: arm-smmu: Remove Calxeda secure mode quirk Message-ID: <20200228134254.03fc5e1b@donnerap.cambridge.arm.com> In-Reply-To: <20200228105024.GC2395@willie-the-truck> References: <20200218171321.30990-1-robh@kernel.org> <20200218171321.30990-7-robh@kernel.org> <20200218172000.GF1133@willie-the-truck> <20200228100446.GA2395@willie-the-truck> <20200228102556.1dde016e@donnerap.cambridge.arm.com> <20200228105024.GC2395@willie-the-truck> Organization: ARM X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; aarch64-unknown-linux-gnu) MIME-Version: 1.0 List-Id: Cc: Mark Langsdorf , kvm@vger.kernel.org, Viresh Kumar , "open list:LIBATA SUBSYSTEM \(Serial and Parallel ATA drivers\)" , linux-clk , Rob Herring , soc@kernel.org, Daniel Lezcano , devicetree@vger.kernel.org, Jon Loeliger , "open list:THERMAL" , Alex Williamson , Tony Luck , Alexander Graf , Mauro Carvalho Chehab , "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" , linux-edac , Jens Axboe , Matthias Brugger , Stephen Boyd , netdev , Cornelia Huck , "Rafael J. Wysocki" , "linux-kernel@vger.kernel.org" , Linux IOMMU , Robert Richter , James Morse , Borislav Petkov , Robin Murphy , "David S. Miller" X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Fri, 28 Feb 2020 10:50:25 +0000 Will Deacon wrote: > On Fri, Feb 28, 2020 at 10:25:56AM +0000, Andre Przywara wrote: > > On Fri, 28 Feb 2020 10:04:47 +0000 > > Will Deacon wrote: > > > > Hi, > > > > > On Tue, Feb 25, 2020 at 04:01:54PM -0600, Rob Herring wrote: > > > > On Tue, Feb 18, 2020 at 11:20 AM Will Deacon wrote: > > > > > > > > > > On Tue, Feb 18, 2020 at 11:13:16AM -0600, Rob Herring wrote: > > > > > > Cc: Will Deacon > > > > > > Cc: Robin Murphy > > > > > > Cc: Joerg Roedel > > > > > > Cc: iommu@lists.linux-foundation.org > > > > > > Signed-off-by: Rob Herring > > > > > > --- > > > > > > Do not apply yet. > > > > > > > > > > Pleeeeease? ;) > > > > > > > > > > > drivers/iommu/arm-smmu-impl.c | 43 ----------------------------------- > > > > > > 1 file changed, 43 deletions(-) > > > > > > > > > > Yes, I'm happy to get rid of this. Sadly, I don't think we can remove > > > > > anything from 'struct arm_smmu_impl' because most implementations fall > > > > > just short of perfect. > > > > > > > > > > Anyway, let me know when I can push the button and I'll queue this in > > > > > the arm-smmu tree. > > > > > > > > Seems we're leaving the platform support for now, but I think we never > > > > actually enabled SMMU support. It's not in the dts either in mainline > > > > nor the version I have which should be close to what shipped in > > > > firmware. So as long as Andre agrees, this one is good to apply. > > > > > > Andre? Can I queue this one for 5.7, please? > > > > I was wondering how much of a pain it is to keep it in? AFAICS there are > > other users of the "impl" indirection. If those goes away, I would be > > happy to let Calxeda go. > > The impl stuff is new, so we'll keep it around. The concern is more about > testing (see below). > > > But Eric had the magic DT nodes to get the SMMU working, and I used that > > before, with updating the DT either on flash or dynamically via U-Boot. > > What did you actually use the SMMU for, though? The > 'arm_iommu_create_mapping()' interface isn't widely used and, given that > highbank doesn't support KVM, the use-cases for VFIO are pretty limited > too. AFAIK Highbank doesn't have the SMMU, probably mostly for that reason. I have a DT snippet for Midway, and that puts the MMIO base at ~36GB, which is not possible on Highbank. So I think that the quirk is really meant and needed for Midway. > > So I don't know exactly *how* desperate you are with removing this, or if > > there are other reasons than "negative diffstat", but if possible I would > > like to keep it in. > > It's more that we *do* make quite a lot of changes to the arm-smmu driver > and it's never tested with this quirk. If you're stepping up to run smmu > tests on my queue for each release on highbank, then great, but otherwise > I'd rather not carry the code for fun. The change in diffstat is minimal > (we're going to need to hooks for nvidia, who broke things in a different > way). I am about to set up some more sophisticated testing, and will include some SMMU bits in it. Cheers, Andre. > Also, since the hooks aren't going away, if you /do/ end up using the SMMU > in future, then we could re-add the driver quirk without any fuss. > > Will _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu