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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,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 21038C3B1A4 for ; Fri, 14 Feb 2020 16:59:19 +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 E62732067D for ; Fri, 14 Feb 2020 16:59:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="kbciHYMm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E62732067D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com 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-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=oo6yCNgBZuoMIOWxXzFUdD7bcjguT1Ugqkte4YaRyLs=; b=kbciHYMmhFEqycftt7aQ0g/I3 ksnehgr3KUp/G4Sfo0HjJyC6oOIYl6eNh/hqgQ3BK7GGAtzkE03WyC1HbXZUSDydC30tkpQR/ZJsf E0jTgAO3d+35M8D8oBQMr9rhnhlwwhqibW7E22yLBYKDsuNduIwPGHB6QlUQzFIT/OR3zoD0ehcIf GRTnYbY7rZCDYd89ZWTe9Nm/d2iGQ9O+yG83JZdGl3MlyW019MFqqO9BcoRhCXhuYHOsz5XDvCU39 VwU8rJrdr6hn83fCI7/R9QFmAGPHOIGoHngxsPMEqB40RRU0BXgIhr/QiKNo1qDRPs3I7Idk2QJn7 JH7cHiSMA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1j2eJ5-00086U-NA; Fri, 14 Feb 2020 16:59:11 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1j2dqr-0006E9-6y for linux-arm-kernel@lists.infradead.org; Fri, 14 Feb 2020 16:30:15 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id ACE4C328; Fri, 14 Feb 2020 08:29:55 -0800 (PST) Received: from [10.1.196.37] (e121345-lin.cambridge.arm.com [10.1.196.37]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 95FC63F68E; Fri, 14 Feb 2020 08:29:45 -0800 (PST) Subject: Re: [EXT] Re: [PATCH] bus: fsl-mc: Add ACPI support for fsl-mc To: Pankaj Bansal , Marc Zyngier References: <1580198925-50411-1-git-send-email-makarand.pawagi@nxp.com> <20200128110916.GA491@e121166-lin.cambridge.arm.com> <12531d6c569c7e14dffe8e288d9f4a0b@kernel.org> <7349fa0e6d62a3e0d0e540f2e17646e0@kernel.org> From: Robin Murphy Message-ID: <7e1ab651-1eb5-b461-1d21-6fd5c8f3ade8@arm.com> Date: Fri, 14 Feb 2020 16:29:40 +0000 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-GB X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200214_083001_463528_1516F217 X-CRM114-Status: GOOD ( 16.07 ) 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: Calvin Johnson , "stuyoder@gmail.com" , "nleeder@codeaurora.org" , Ioana Ciornei , Cristi Sovaiala , Hanjun Guo , Will Deacon , Lorenzo Pieralisi , "jon@solid-run.com" , Russell King , ACPI Devel Maling List , Len Brown , Jason Cooper , Andy Wang , Makarand Pawagi , Varun Sethi , Thomas Gleixner , linux-arm-kernel , Laurentiu Tudor , Paul Yang , Ard Biesheuvel , "netdev@vger.kernel.org" , "Rafael J. Wysocki" , Linux Kernel Mailing List , Shameerali Kolothum Thodi , Sudeep Holla Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 14/02/2020 3:58 pm, Pankaj Bansal wrote: [...] >> I don't understand what you mean. Platform MSI using IORT uses the DevID of >> end-points. How could the ITS could work without specifying a DevID? >> See for example how the SMMUv3 driver uses platform MSI. > > DevID is input ID for PCIe devices. BUT what would be the input ID for platform device? Are we saying that Platform devices can't specify an Input ID ? No, from the IORT perspective, the input for the ID mappings belonging to a root complex is the PCI requester ID. The (ITS) DevID is the ultimate *output* of a root complex mapping. Whilst you can indeed represent the MC as a black-box Named Component with an ID mapping range not using the "single mapping" flag, that means your input IDs come from some device-specific domain beyond the scope of IORT. That's why you can't easily get away from your special bus integration code. >>> While, IORT spec doesn't specify any such limitation. >>> >>> we can easily update iort.c to remove this limitation. >>> But, I am not sure how the input id would be passed from platform MSI >>> GIC layer to IORT. >>> Most obviously, the input id should be supplied by dev itself. >> >> Why should the device know about its own ID? That's a bus/interconnect thing. >> And nothing should be passed *to* IORT. IORT is the source. > > IORT is translation between Input IDs <-> Output IDs. The Input ID is still expected to be passed to parse IORT table. ...except for single mappings, where the input ID is ignored and the output ID is the "source", which is exactly what iort_node_get_id() deals with for devices represented in IORT. With what you're talking about, "the device" is *not* represented in IORT, but is something beyond the MC 'bridge'. Now it probably is technically possible to handle that somehow, but it's definitely not something that the existing code was ever designed to anticipate. Robin. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel