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, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 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 505E7C48BE5 for ; Thu, 17 Jun 2021 17:12:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 38F5D613BF for ; Thu, 17 Jun 2021 17:12:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231896AbhFQROq convert rfc822-to-8bit (ORCPT ); Thu, 17 Jun 2021 13:14:46 -0400 Received: from frasgout.his.huawei.com ([185.176.79.56]:3264 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230028AbhFQROq (ORCPT ); Thu, 17 Jun 2021 13:14:46 -0400 Received: from fraeml705-chm.china.huawei.com (unknown [172.18.147.201]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4G5T2f0kGqz6J68h; Fri, 18 Jun 2021 01:05:30 +0800 (CST) Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by fraeml705-chm.china.huawei.com (10.206.15.54) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Thu, 17 Jun 2021 19:12:35 +0200 Received: from localhost (10.52.120.116) by lhreml710-chm.china.huawei.com (10.201.108.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Thu, 17 Jun 2021 18:12:34 +0100 Date: Thu, 17 Jun 2021 18:12:25 +0100 From: Jonathan Cameron To: Dan Williams CC: Chris Browy , , "Linux PCI" , Ben Widawsky , "Bjorn Helgaas" , Linux ACPI , "Schofield, Alison" , Vishal L Verma , "Weiny, Ira" , "Lorenzo Pieralisi" , Linuxarm , Fangjian Subject: Re: [RFC PATCH 1/2] PCI/doe: Initial support PCI Data Object Exchange Message-ID: <20210617181225.0000105b@Huawei.com> In-Reply-To: <20210318142529.00001507@Huawei.com> References: <20210310180306.1588376-1-Jonathan.Cameron@huawei.com> <20210310180306.1588376-2-Jonathan.Cameron@huawei.com> <20210316162952.00001ab7@Huawei.com> <6F0B8DDD-E661-40C8-839B-1B77998EFF23@avery-design.com> <20210318142529.00001507@Huawei.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; i686-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT X-Originating-IP: [10.52.120.116] X-ClientProxiedBy: lhreml739-chm.china.huawei.com (10.201.108.189) To lhreml710-chm.china.huawei.com (10.201.108.61) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Thu, 18 Mar 2021 14:25:29 +0000 Jonathan Cameron wrote: > On Wed, 17 Mar 2021 18:30:26 -0700 > Dan Williams wrote: > > > Btw your mailer does something odd with the "In-Reply-To:" field, I > > need to fix it up manually to include your address. > > > > On Tue, Mar 16, 2021 at 4:28 PM Chris Browy wrote: > > > > > > Please address and clarify 2 queries below... > > > > > > > > > > On Mar 16, 2021, at 2:14 PM, Dan Williams wrote: > > > > > > > > On Tue, Mar 16, 2021 at 9:31 AM Jonathan Cameron > > > > wrote: > > > >> > > > >> On Mon, 15 Mar 2021 12:45:49 -0700 > > > >> Dan Williams wrote: > > > >> > > > >>> Hey Jonathan, happy to see this, some comments below... > > > >> > > > >> Hi Dan, > > > >> > > > >> Thanks for taking a look! > > > >> > > > >>> > > > >>> On Wed, Mar 10, 2021 at 10:08 AM Jonathan Cameron > > > >>> wrote: > > > >>>> > > > >>>> Introduced in an ECN to the PCI 5.0, DOE provides a config space > > > >>>> based mailbox with standard protocol discovery. Each mailbox > > > >>>> is accessed through a DOE PCIE Extended Capability. > > > >>>> > > > >>>> A device may have 1 or more DOE mailboxes, each of which is allowed > > > >>>> to support any number of protocols (some DOE protocols > > > >>>> specifications apply additional restrictions). A given protocol > > > >>>> may be supported on more than one DOE mailbox on a given function. > > > >>> > > > >>> Are all those protocol instances shared? > > > >>> I'm trying to mental model > > > >>> whether, for example, an auxiliary driver instance could be loaded per > > > >>> DOE mailbox, or if there would need to be coordination of a given > > > >>> protocol no matter how many DOE mailboxes on that device implemented > > > >>> that protocol. > > > >> > > > >> Just to check I've understood corectly, you mean multiple instances of same > > > >> protocol across different DOE mailboxes on a given device? > > > >> > > > > > > > > Right. > > > > > > Could you confirm this case for clarity? A CXL device may have multiple VF/PF. > > > For example, PF=0 could have one or more DOE instances for CDAT protocol. > > > The driver will scan PF=0 for all DOE instances and finding one or more of CDAT > > > protocol will combine/manage them. I had not considered multiple CDAT tables > > > for single PF. For CXL devices with multiple PF’s the same process would be > > > carried out on PF=1-N. > > > > This patch has nothing to do with CXL. This is a general discussion of > > how a PCIE device implements a DOE mailbox or set of mailboxes. The > > DOE definition is PF-only afaics from the DOE specification. > > > > The CXL specification only says that a device can implement a CDAT per > > DOE capability instance, so the CXL spec does not limit the number of > > DOE instances to 1, but I can't think of a practical reason to support > > more than one. > > > > [..] > > > >>> https://cfp.osfc.io/media/osfc2020/submissions/ECQ88N/resources/An_open_source_SPDM_implementation_for_secure_devi_kmIgAQe.pdf > > > >> > > > >> Nice! Looking at CMA / IDE emulation was on my todo list and that looks like > > > >> it might make that job a lot easier. > > > > > > Would it be useful to integrate the openspdm’s SpdmResponderEmu.c onto the QEMU’s CXL Type3 Device’s > > > DOE backend for CMA/IDE testing? Doesn’t look hard to do. > > > > Yes, I do think it would be useful. > > Agreed. Very useful indeed. > > Jonathan > Hi Chris, Just wondering if this qemu/openspdm integration was something your team have had time to look at? I'd like to ideally get a second DOE usecase implemented on the Linux side to prove out the implementation. If it's fallen off your near term todo list I might see if I can hack something together in the meantime. Thanks, Jonathan