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=-7.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,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 C3CD1C4363C for ; Mon, 21 Sep 2020 17:58:45 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 6A31C2193E for ; Mon, 21 Sep 2020 17:58:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="yQc6JhDC"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="b3e4bLWq" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6A31C2193E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=/ThRZdHcx9FtY7fn4uBxCYzu+frl96eaXHogzrIY2c4=; b=yQc6JhDCsnvnbtNZLbcadrWnE 6DAezWftLia3bT/SlWoxuLhGAlhL3m8n+5SDVb3Qf3/VxX4yViLzGJ7UZ/UZSpINkiOdg/5Pm4jK9 +R/Bd3PgnljyDUdWWK5rQnZ/hzicnyOJbRCaT2GT5fkewK3aibN4eu1Jl49vOF5FCJ0Dyt9hZs78O cNKeXHxvnjZd04XmjAEL40e3dOzGjaGS2DsmFMmSdpnCDdbRj30y/9zMViEf/LFhmH2aOTxaaoNey /6AIc0t166u7uH2r9w/6tBrywvpiuyJqXXh6XhOEsY4v03SNigA5fXLAsMyTobQqUijmKyW5rF5LW lZCrK6YPQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kKQ49-0005pB-1v; Mon, 21 Sep 2020 17:57:29 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kKQ45-0005oH-GT; Mon, 21 Sep 2020 17:57:26 +0000 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 35E5B20BED; Mon, 21 Sep 2020 17:57:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600711044; bh=MViJLr32Rfq7YAhifD5/NIE9W+70lqX9C47Hh7THkOA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=b3e4bLWq5uf1a8R/Zqrvx5GkxrmWFkVBJ7bYxNE+krlPNWfqlQf3S3tTvNN0+xB28 CxpT0M0IBlW+szKcCIPx5TFtZcwgWVBp8MOHvIS4TTWK1EOcQWjVDDWz/daGwhF3q9 l5v3MQq16B/JXdNNa/Qs+ZKHN5sUIxuisx9oOSbM= Date: Mon, 21 Sep 2020 18:57:19 +0100 From: Will Deacon To: Robin Murphy Subject: Re: [PATCH 1/3] iommu/io-pgtable-arm: Support coherency for Mali LPAE Message-ID: <20200921175717.GF3141@willie-the-truck> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200921_135725_622219_3AB093DB X-CRM114-Status: GOOD ( 13.28 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: robh@kernel.org, tomeu.vizoso@collabora.com, narmstrong@baylibre.com, khilman@baylibre.com, dri-devel@lists.freedesktop.org, steven.price@arm.com, iommu@lists.linux-foundation.org, alyssa.rosenzweig@collabora.com, linux-amlogic@lists.infradead.org, linux-arm-kernel@lists.infradead.org, jbrunet@baylibre.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Sep 16, 2020 at 12:51:05AM +0100, Robin Murphy wrote: > Midgard GPUs have ACE-Lite master interfaces which allows systems to > integrate them in an I/O-coherent manner. It seems that from the GPU's > viewpoint, the rest of the system is its outer shareable domain, and so > even when snoop signals are wired up, they are only emitted for outer > shareable accesses. As such, setting the TTBR_SHARE_OUTER bit does > indeed get coherent pagetable walks working nicely for the coherent > T620 in the Arm Juno SoC. I can't help but think some of this commentary deserves to be in the code as well. Do you know if this sort of thing is done for other SoCs too, or is this just a Juno quirk? Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel