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=-2.2 required=3.0 tests=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 6F801C3F2CE for ; Wed, 4 Mar 2020 17:40:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4DAE820732 for ; Wed, 4 Mar 2020 17:40:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727543AbgCDRkv (ORCPT ); Wed, 4 Mar 2020 12:40:51 -0500 Received: from 8bytes.org ([81.169.241.247]:50038 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727528AbgCDRkv (ORCPT ); Wed, 4 Mar 2020 12:40:51 -0500 Received: by theia.8bytes.org (Postfix, from userid 1000) id 4515C2E2; Wed, 4 Mar 2020 18:40:50 +0100 (CET) Date: Wed, 4 Mar 2020 18:40:46 +0100 From: Joerg Roedel To: Jean-Philippe Brucker Cc: "Michael S. Tsirkin" , Auger Eric , iommu@lists.linux-foundation.org, virtualization@lists.linux-foundation.org, linux-pci@vger.kernel.org, bhelgaas@google.com, jasowang@redhat.com, kevin.tian@intel.com, sebastien.boeuf@intel.com, jacob.jun.pan@intel.com, robin.murphy@arm.com Subject: Re: [PATCH v2 1/3] iommu/virtio: Add topology description to virtio-iommu config space Message-ID: <20200304174045.GC3315@8bytes.org> References: <20200228172537.377327-1-jean-philippe@linaro.org> <20200228172537.377327-2-jean-philippe@linaro.org> <20200302161611.GD7829@8bytes.org> <9004f814-2f7c-9024-3465-6f9661b97b7a@redhat.com> <20200303130155.GA13185@8bytes.org> <20200303084753-mutt-send-email-mst@kernel.org> <20200303155318.GA3954@8bytes.org> <20200303105523-mutt-send-email-mst@kernel.org> <20200304133707.GB4177@8bytes.org> <20200304153821.GE646000@myrica> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200304153821.GE646000@myrica> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Mar 04, 2020 at 04:38:21PM +0100, Jean-Philippe Brucker wrote: > I agree with this. The problem is I don't know how to get a new ACPI table > or change an existing one. It needs to go through the UEFI forum in order > to be accepted, and I don't have any weight there. I've been trying to get > the tiny change into IORT for ages. I haven't been given any convincing > reason against it or offered any alternative, it's just stalled. The > topology description introduced here wasn't my first choice either but > unless someone can help finding another way into ACPI, I don't have a > better idea. A quote from the ACPI Specification (Version 6.3, Section 5.2.6, Page 119): Table signatures will be reserved by the ACPI promoters and posted independently of this specification in ACPI errata and clarification documents on the ACPI web site. Requests to reserve a 4-byte alphanumeric table signature should be sent to the email address info@acpi.info and should include the purpose of the table and reference URL to a document that describes the table format. Tables defined outside of the ACPI specification may define data value encodings in either little endian or big endian format. For the purpose of clarity, external table definition documents should include the endian-ness of their data value encodings. So it sounds like you need to specifiy the table format and send a request to info@acpi.info to get a table signature for it. Regards, Joerg