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 8C80CC41514 for ; Thu, 15 Aug 2019 15:33:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 60CD920644 for ; Thu, 15 Aug 2019 15:33:10 +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" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730068AbfHOPdJ (ORCPT ); Thu, 15 Aug 2019 11:33:09 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:35206 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730049AbfHOPdJ (ORCPT ); Thu, 15 Aug 2019 11:33:09 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 1198660736; Thu, 15 Aug 2019 15:33:08 +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 Cc: 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 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-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1565216500-28506-1-git-send-email-jcrouse@codeaurora.org> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.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