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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 B7059C3A589 for ; Thu, 15 Aug 2019 15:33:09 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (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 7A45F20644 for ; Thu, 15 Aug 2019 15:33:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="i7Yfe8lk"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="RzWtWebS" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7A45F20644 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 3FF21C87; Thu, 15 Aug 2019 15:33:09 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 81981B49 for ; Thu, 15 Aug 2019 15:33:08 +0000 (UTC) Received: from smtp.codeaurora.org (smtp.codeaurora.org [198.145.29.96]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 283B667F for ; Thu, 15 Aug 2019 15:33:08 +0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1000) id F324F607CA; Thu, 15 Aug 2019 15:33:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1565883188; bh=uo5H+y/d8CeAGVlGgEqg/owuTjfwykTO28LcSJ+xr/4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=i7Yfe8lkksQXtPilSJpmG+DZTo3/5PsbbvskTeYAjHXEL4LcUMrAsZABl47mqB+cZ Uk/Wo6tJWK6WoPNxaHtykreYkd7TpL/7J5jsxvqAx1fHj+PAt0cIXmR5bkkR0Fls4j /ApoqDqtGDwO07uhw/kj/j9okcX2Dpkx68NQ6HIU= Received: from jcrouse1-lnx.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: jcrouse@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 09845602DB; Thu, 15 Aug 2019 15:33:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1565883186; bh=uo5H+y/d8CeAGVlGgEqg/owuTjfwykTO28LcSJ+xr/4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=RzWtWebSM6sga9d+OFbdNomQXt2erULsaPlh8pnTHBZtZyGoEFu/YQWnwWPs72tQk qOKjG9KEdXR6TLhBuDZEmtumeRgnsWuqmbxssYDp3D8XHF0kWV1JwF/qKTDVRqvmsX pE5VXpZ0oG+3PfHMM6LMzK8I5mAQKLk7o64a0K2M= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 09845602DB Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=jcrouse@codeaurora.org Date: Thu, 15 Aug 2019 09:33:04 -0600 From: Jordan Crouse To: freedreno@lists.freedesktop.org Subject: Re: [Freedreno] [PATCH v3 0/2] iommu/arm-smmu: Split pagetable support Message-ID: <20190815153304.GD28465@jcrouse1-lnx.qualcomm.com> Mail-Followup-To: freedreno@lists.freedesktop.org, Rob Herring , Will Deacon , jean-philippe.brucker@arm.com, linux-arm-msm@vger.kernel.org, Joerg Roedel , linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, Zhen Lei , robin.murphy@arm.com, linux-arm-kernel@lists.infradead.org References: <1565216500-28506-1-git-send-email-jcrouse@codeaurora.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1565216500-28506-1-git-send-email-jcrouse@codeaurora.org> User-Agent: Mutt/1.5.24 (2015-08-30) Cc: Rob Herring , jean-philippe.brucker@arm.com, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, Will Deacon , linux-arm-kernel@lists.infradead.org, robin.murphy@arm.com X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 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 Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org On Wed, Aug 07, 2019 at 04:21:38PM -0600, Jordan Crouse wrote: > (Sigh, resend. I freaked out my SMTP server) > > This is part of an ongoing evolution for enabling split pagetable support for > arm-smmu. Previous versions can be found [1]. > > In the discussion for v2 Robin pointed out that this is a very Adreno specific > use case and that is exactly true. Not only do we want to configure and use a > pagetable in the TTBR1 space, we also want to configure the TTBR0 region but > not allocate a pagetable for it or touch it until the GPU hardware does so. As > much as I want it to be a generic concept it really isn't. > > This revision leans into that idea. Most of the same io-pgtable code is there > but now it is wrapped as an Adreno GPU specific format that is selected by the > compatible string in the arm-smmu device. > > Additionally, per Robin's suggestion we are skipping creating a TTBR0 pagetable > to save on wasted memory. > > This isn't as clean as I would like it to be but I think that this is a better > direction than trying to pretend that the generic format would work. > > I'm tempting fate by posting this and then taking some time off, but I wanted > to try to kick off a conversation or at least get some flames so I can try to > refine this again next week. Please take a look and give some advice on the > direction. Will, Robin - Modulo the impl changes from Robin, do you think that using a dedicated pagetable format is the right approach for supporting split pagetables for the Adreno GPU? If so, then is adding the changes to io-pgtable-arm.c possible for 5.4 and then add the implementation specific code on top of Robin's stack later or do you feel they should come as part of a package deal? Jordan > Jordan Crouse (2): > iommu/io-pgtable-arm: Add support for ARM_ADRENO_GPU_LPAE io-pgtable > format > iommu/arm-smmu: Add support for Adreno GPU pagetable formats > > drivers/iommu/arm-smmu.c | 8 +- > drivers/iommu/io-pgtable-arm.c | 214 ++++++++++++++++++++++++++++++++++++++--- > drivers/iommu/io-pgtable.c | 1 + > include/linux/io-pgtable.h | 2 + > 4 files changed, 209 insertions(+), 16 deletions(-) > > -- > 2.7.4 > > _______________________________________________ > Freedreno mailing list > Freedreno@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/freedreno -- The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu