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=-5.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, 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 5B252C433E8 for ; Mon, 20 Jul 2020 09:25:18 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 2C9B52176B for ; Mon, 20 Jul 2020 09:25:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=xen.org header.i=@xen.org header.b="LQpMvRz5" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2C9B52176B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=xen.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jxS2c-0004CR-NM; Mon, 20 Jul 2020 09:24:58 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jxS2b-0004CM-9f for xen-devel@lists.xenproject.org; Mon, 20 Jul 2020 09:24:57 +0000 X-Inumbo-ID: dfd99b66-ca6a-11ea-8480-bc764e2007e4 Received: from mail.xenproject.org (unknown [104.130.215.37]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id dfd99b66-ca6a-11ea-8480-bc764e2007e4; Mon, 20 Jul 2020 09:24:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xen.org; s=20200302mail; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:Cc:To:Subject:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=xizyXMNDeLs4ZLnctySaz18NXv/aXzwDcBu6IFSNWNo=; b=LQpMvRz5l4IfQD5mNrzLdxLyL7 tv8D4lxepWNYRUYdLLwdfq/4Yc9CtBG6bSPwN7GM2ysjCzzl/Hdi0dSljCkUrY9BXDWWbuW13AfUs 2tIYs4tjyNhSD5TjYEigA9NhUr+oiKkwZLA5mp9uorc1SwGZOlEY12xk8516Z3pUheZk=; Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jxS2Y-0001Tr-FH; Mon, 20 Jul 2020 09:24:54 +0000 Received: from 54-240-197-239.amazon.com ([54.240.197.239] helo=a483e7b01a66.ant.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1jxS2Y-0006Si-72; Mon, 20 Jul 2020 09:24:54 +0000 Subject: Re: RFC: PCI devices passthrough on Arm design proposal To: =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= References: <20200717144139.GU7191@Air-de-Roger> <90AE8DAB-2223-46DC-A263-D78365E5435E@arm.com> <20200717150507.GW7191@Air-de-Roger> <20200717153043.GX7191@Air-de-Roger> <20200717160834.GA7191@Air-de-Roger> <0c76b6a0-2242-3bbd-9740-75c5580e93e8@xen.org> <20200720084734.GE7191@Air-de-Roger> From: Julien Grall Message-ID: Date: Mon, 20 Jul 2020 10:24:52 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200720084734.GE7191@Air-de-Roger> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 8bit X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Rahul Singh , Bertrand Marquis , Stefano Stabellini , Jan Beulich , "xen-devel@lists.xenproject.org" , nd , Julien Grall Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" Hi Roger, On 20/07/2020 09:47, Roger Pau Monné wrote: > On Fri, Jul 17, 2020 at 05:18:46PM +0100, Julien Grall wrote: >>> Do you really need to specify the ECAM and MMIO regions there? >> >> You need to define those values somewhere :). The layout is only shared >> between the tools and the hypervisor. I think it would be better if they are >> defined at the same place as the rest of the layout, so it is easier to >> rework the layout. > > OK, that's certainly a different approach from what x86 uses, where > the guest memory layout is not defined in the public headers. It is mostly a convenience as some addresses are used by both the hypervisor and tools. A guest should use the firmware tables (ACPI/DT) to detect the MMIO regions. > > On x86 my plan would be to add an hypercall that would set the > position of the ECAM region in the guest physmap, and that would be > called by the toolstack during domain construction. It would be possible to use the same on Arm so the hypervisor doesn't use hardcoded values for the ECAM. Cheers, -- Julien Grall