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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id A70EEC3271E for ; Mon, 8 Jul 2024 09:37:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc: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=QbV0J8QAr6aMGdd2V9XdZPlI7wOqyY5RFqXzZcKu688=; b=J0NJeKj2LbPFeTZUg99ukxtx2E 8r4iGDCfKvMBrrjRwQ75xUQbCHbu3rnVqLIg06vT/pVz5ys2MprAV2o+ldEK45d9O404qa2EAZBpc P6JDRB434af2lQHmc5D9yXdgBujn9aXpj0SvN0NTVzthJ12P010tMo/9XW0mGhaBb+nUNfzF6KGFJ kmnQRct6R+8glUxAZKOMcG+BWAqPUGXDkZ+EyJSUIvZdtcg5Q2HzAo2C8/Y1UtglnOr0nZUGDl7GV JCD5O4dgN4wkk4yNT3/fXAXUM8nQ9FzNQZPOAmfQEmU5NwBngzKVpEJkJEOLO65MeX38IIBfQZ4mu u1cugzzQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sQknn-00000003II0-28p3; Mon, 08 Jul 2024 09:36:55 +0000 Received: from sin.source.kernel.org ([145.40.73.55]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sQknY-00000003IED-3RsX for linux-arm-kernel@lists.infradead.org; Mon, 08 Jul 2024 09:36:42 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 7974ECE0AF0; Mon, 8 Jul 2024 09:36:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B69F8C116B1; Mon, 8 Jul 2024 09:36:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1720431397; bh=Xiw5vB0052Gl+ZR1KcxMzIPi0K4sjO2ctTIPiltoYm4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nD71evyHcTYyqnKhYOjZ2rvE1kNbKK4fnjwv9H9/q4Gl4v77btpI0VPjF5Axl9uxQ zf6kWsNDkwMq3R/ag7pDQ3aQnkKN6QAosSO/GatB5xms1cHhBP9NfbM4sFW7DiYnPx irzKjsb2C6DVkaGGQ0j3WkLeMJE27TFQOOkFhxoMnck7JKfbarrXcEy3q/y/MHPiBQ 0VFEB5KFEKtkNZLvbKTAgqYbo2rfyPNP5kH1Le9VrjSKh80LCf8+lXwpNgyTZke2Rc 5//FidY4WjFL3DuCymBmccvJMLfqgvNBdG4jPHKE1cIegjJ9v888E39LlJlN6TnBUA 52ibJZjxn41bg== Date: Mon, 8 Jul 2024 10:36:31 +0100 From: Will Deacon To: Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= Cc: Jean-Philippe Brucker , lpieralisi@kernel.org, robh@kernel.org, bhelgaas@google.com, krzk+dt@kernel.org, conor+dt@kernel.org, liviu.dudau@arm.com, sudeep.holla@arm.com, joro@8bytes.org, robin.murphy@arm.com, nicolinc@nvidia.com, ketanp@nvidia.com, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, devicetree@vger.kernel.org Subject: Re: [PATCH v2 1/3] dt-bindings: PCI: generic: Add ats-supported property Message-ID: <20240708093630.GA11302@willie-the-truck> References: <20240607105415.2501934-2-jean-philippe@linaro.org> <20240607105415.2501934-3-jean-philippe@linaro.org> <20240706032431.GH1195499@rocinante> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20240706032431.GH1195499@rocinante> 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-20240708_023641_074585_5B3CCB6A X-CRM114-Status: GOOD ( 15.21 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Krzysztof, On Sat, Jul 06, 2024 at 12:24:31PM +0900, Krzysztof Wilczyński wrote: > > Add a way for firmware to tell the OS that ATS is supported by the PCI > > root complex. An endpoint with ATS enabled may send Translation Requests > > and Translated Memory Requests, which look just like Normal Memory > > Requests with a non-zero AT field. So a root controller that ignores the > > AT field may simply forward the request to the IOMMU as a Normal Memory > > Request, which could end badly. In any case, the endpoint will be > > unusable. > > > > The ats-supported property allows the OS to only enable ATS in endpoints > > if the root controller can handle ATS requests. Only add the property to > > pcie-host-ecam-generic for the moment. For non-generic root controllers, > > availability of ATS can be inferred from the compatible string. > > Applied to dt-bindings, thank you! > > [1/1] dt-bindings: PCI: generic: Add ats-supported property > https://git.kernel.org/pci/pci/c/631b2e7318d45 FWIW: I already picked this up in the IOMMU tree last week. If you need it to avoid a conflict, then you can pull from the pci/ats branch: https://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux.git/commit/?h=pci/ats&id=40929e8e5449a18bc98baf7a907dd6674bd60049 Cheers, Will