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=-4.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 2F788C32792 for ; Mon, 30 Sep 2019 18:38:04 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 F1F32224D7 for ; Mon, 30 Sep 2019 18:38:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="cJYYv2RN"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="y9r7bli4" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F1F32224D7 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+infradead-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=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:To:Subject:Message-ID:Date:From: In-Reply-To:References:MIME-Version:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=AiA4ZRaJb+8/+T6pFlwGo6jOrs+tCTY1rpZCgFamxpI=; b=cJYYv2RNVBjx5R lNum7fCPO8+FiYALrHk2O+EuApwUQEPCLVu6DhoW3m5ga0weGbDBydqyw6Sb8RBf94WXDaw0O05pw jA68bOvriSe2z/oNRlwvGVFR0TuJ9jV8iaH1xnHaO8UTrBD+EieI7Cw0VCzCJVFSuN88aLIbWyWtB ryR6ZAqPpy99v0QzyGljvk9rmlXIk+uxW8UyNk29F7b0oa6+7bAObvu6wlnXOBWt83cH222NmhJ48 0HTG5FQzFEVPRWMTiiW9z9TDYLjjL2z8bbJSV4eHU0pBc4RpW5vKkWRN4RI1zAdD+pMlm1WxYIR9H COGTJZnZBuwjh1TRl+AA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1iF0Yc-0004vI-HN; Mon, 30 Sep 2019 18:38:02 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.2 #3 (Red Hat Linux)) id 1iF0XM-0003Yg-NG for linux-arm-kernel@lists.infradead.org; Mon, 30 Sep 2019 18:36:46 +0000 Received: from mail-qt1-f179.google.com (mail-qt1-f179.google.com [209.85.160.179]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B700D224D7 for ; Mon, 30 Sep 2019 18:36:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569868603; bh=1tL/OZOkCQgzZnBFplZTU+ckRrS4/sDh6E9zhlDzq/c=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=y9r7bli47fVGj+4fjTYQ6PAXVa0UI+u3pZnzIoPcyL5ummMRbOrFM8Z8ezx0c9O9M OWWNIjwXkelXIdFKvH0eTzLFL3aK4P1ZUn6RPdwLnHsRpcYvtGERwjcypBmW+az2Ot OoolrSVYpG+lt/hn0Iww7kUj5dPAJgA21mXP8u00= Received: by mail-qt1-f179.google.com with SMTP id n1so18293618qtp.8 for ; Mon, 30 Sep 2019 11:36:43 -0700 (PDT) X-Gm-Message-State: APjAAAWgiNJ1p1bsp4T1QC+wkEV/lUtIbnGYQFsdO3I8t9HfsN++27Bu Pcu4sOuqRm3XNA6r8cRm66jY9URTHglkAvkFfg== X-Google-Smtp-Source: APXvYqzrW8P34cQHwAL7kkHCPf/H7Il3VJU7gB5YH+0CDpc3kU87kepa13cpt99giygGkK5bkJVuq6phphJeVpRAcNg= X-Received: by 2002:a05:6214:11b4:: with SMTP id u20mr19329160qvv.200.1569868602914; Mon, 30 Sep 2019 11:36:42 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Rob Herring Date: Mon, 30 Sep 2019 13:36:32 -0500 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 3/3] iommu/io-pgtable-arm: Allow coherent walks for Mali To: Robin Murphy X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190930_113644_815601_B0B78D09 X-CRM114-Status: GOOD ( 15.03 ) 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: Tomeu Vizoso , Neil Armstrong , Joerg Roedel , Steven Price , Linux IOMMU , Will Deacon , "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Sep 30, 2019 at 9:11 AM 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. > > Exploiting coherency for data accesses is more of a challenge, since > not only do we need to get the GPU MMU attributes right but we'd also > have to avoid pgprot_writecombine creating an attribute mismatch on > the CPU side, so we won't try wiring that up just yet. > > Reviewed-by: Steven Price > Signed-off-by: Robin Murphy > --- > drivers/iommu/io-pgtable-arm.c | 3 +++ > 1 file changed, 3 insertions(+) Reviewed-by: Rob Herring _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel