From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: virtio-comment-return-1172-cohuck=redhat.com@lists.oasis-open.org Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 3BB0D986050 for ; Fri, 27 Mar 2020 17:19:51 +0000 (UTC) References: <20200227113735.23605-1-peter.hilber@opensynergy.com> <20200317192053.15665-1-peter.hilber@opensynergy.com> From: Alex =?utf-8?Q?Benn=C3=A9e?= In-reply-to: <20200317192053.15665-1-peter.hilber@opensynergy.com> Date: Fri, 27 Mar 2020 17:19:47 +0000 Message-ID: <87369tn2a4.fsf@linaro.org> MIME-Version: 1.0 Subject: [virtio-comment] Re: [virtio-dev] [PATCH v3] Add virtio SCMI device specification Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable To: Peter Hilber Cc: virtio-comment@lists.oasis-open.org, linux-arm-kernel@lists.infradead.org, Souvik.Chakravarty@arm.com, Sudeep.Holla@arm.com, virtio-dev@lists.oasis-open.org List-ID: Peter Hilber writes: > This patch proposes a new virtio device for the Arm SCMI protocol. > > The device provides a simple transport for the Arm SCMI protocol[1]. The > *S*ystem *C*ontrol and *M*anagement *I*nterface protocol allows speaking > to system controllers that allow orchestrating things like power > management, system state management and sensor access. The SCMI protocol > is used on SoCs where multiple cores and co-processors need access to > these resources. > > The virtio transport allows making use of this protocol in virtualized > systems. > > [1] https://developer.arm.com/docs/den0056/b > > Signed-off-by: Peter Hilber > + > +\subsubsection{Shared Memory Operation} > + > +Various SCMI protocols define statistics shared memory regions (for > +statistics and sensor values). > + > +\devicenormative{\paragraph}{Shared Memory Operation}{Device Types / SCM= I Device / Device Operation / Shared Memory Operation} > + > +If VIRTIO_SCMI_F_SHARED_MEMORY was negotiated, the device MAY implement > +an SCMI statistics shared memory region using a virtio shared memory > +region. AFAICT this is the first usage of shmid in the virtio spec so I have some questions. The spec says: Memory consistency rules vary depending on the region and the device and they will be specified as required by each device. So what are the rules for memory consistency for these regions: - are they read-only w.r.t the guest? (maybe this is implicit?) - how does the guest know when they have been updated? - how goes the guest know it hasn't read a value mid-update? > + > +If the device implements a shared memory region, the device MUST assign > +the corresponding shmid as per the following table: > + > +\begin{tabular}{|l|l|} > +\hline > +SCMI statistics shared memory region & Virtio shmid \\ > +\hline \hline > +Power state statistics shared memory region & 1 \\ > +\hline > +Performance domain statistics shared memory region & 2 \\ > +\hline > +Sensor Values Shared Memory & 3 \\ > +\hline > +Reserved for future use & 4 to 0x7F \\ > +\hline > +Vendor-specific statistics shared memory regions & 0x80 to 0xFF \\ > +\hline > +Reserved for future use & 0x100 and greater \\ > +\hline > +\end{tabular} --=20 Alex Benn=C3=A9e This publicly archived list offers a means to provide input to the=0D OASIS Virtual I/O Device (VIRTIO) TC.=0D =0D In order to verify user consent to the Feedback License terms and=0D to minimize spam in the list archive, subscription is required=0D before posting.=0D =0D Subscribe: virtio-comment-subscribe@lists.oasis-open.org=0D Unsubscribe: virtio-comment-unsubscribe@lists.oasis-open.org=0D List help: virtio-comment-help@lists.oasis-open.org=0D List archive: https://lists.oasis-open.org/archives/virtio-comment/=0D Feedback License: https://www.oasis-open.org/who/ipr/feedback_license.pdf= =0D List Guidelines: https://www.oasis-open.org/policies-guidelines/mailing-lis= ts=0D Committee: https://www.oasis-open.org/committees/virtio/=0D Join OASIS: https://www.oasis-open.org/join/ 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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 DDDDEC43331 for ; Fri, 27 Mar 2020 17:21:35 +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 5E9E9206DB for ; Fri, 27 Mar 2020 17:21:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="nEIrkpKS"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="MGsWVGDw" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5E9E9206DB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org 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-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date: In-reply-to:Subject:To:From:References:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=mXRRZDp5U71qJmIaBkuRnuongJJlau8LI1VvcRG5po0=; b=nEIrkpKShlpZbuVbGeaUxOjgEt NjdZz+0oYC2qYVRbiWDPmtTYnKa/7y+JvYyLPIn5AfsAA+3bTZhNacqRezBlu2693pO4IagSteGxg nNCshR3NSkEJ6IKeIDFxtVFtSahqnu6GLdAZibmG9KemkIGmsVlntmmrSGR9/NuqeN7gAN1axARRA PMT/m+fZH3W6Z1SaHlBjQRPvoaIkPfVy7MJJVYGDijUGB6Go7uU/3uJdQ/l1ZunmAYL7HuD1oUlc3 tzGp6p7w0j2VYpw3mkbBO9wn6vwwVcE2aHcHM8nLEJ5Qdw5l0wDKmQhOZbNqp2rOOth1eDRb97xg4 fvGM5HXA==; 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 1jHsfh-0005BE-6A; Fri, 27 Mar 2020 17:21:29 +0000 Received: from mail-wr1-x442.google.com ([2a00:1450:4864:20::442]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jHse7-0002sF-0t for linux-arm-kernel@lists.infradead.org; Fri, 27 Mar 2020 17:19:59 +0000 Received: by mail-wr1-x442.google.com with SMTP id t7so12290293wrw.12 for ; Fri, 27 Mar 2020 10:19:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=references:user-agent:from:to:cc:subject:in-reply-to:date :message-id:mime-version:content-transfer-encoding; bh=e7d/MiY+Am1dQA8qD50EyJqM0bO753jOUdN3UxYV6lY=; b=MGsWVGDw9oJRYCLOMnN1qSi0yIzAaEHReIFODZuWbpxVRSlPoIL0QbE3wcnFOe6yzZ FF0MRCT43oA8i58c/LXtn8HBBw/NdaKBPfNoYHvamQkdfO/gzPSEVQphpSMKQcoJBEPV JJPbJJDwPOKjnMYgj4bvgkvCiF9z9Y9n7vV+KtCPLzobDK2wXGJ/VabG9g6rKeLkPBhN dceX7XL+k3efpG++uklNRHQZfnh0jbpFJhbmjRCMjS+30pv+uJZc8ODfAbkJ8o7fXvoZ Y3Sg0pxgeXj1O4QCtn+hEovdq1Yq5xEdC0i1X5Nv8Px/Hwgib3me6vhBLhU3tLbwV7FI ygqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:references:user-agent:from:to:cc:subject :in-reply-to:date:message-id:mime-version:content-transfer-encoding; bh=e7d/MiY+Am1dQA8qD50EyJqM0bO753jOUdN3UxYV6lY=; b=foLS0yN3xl8LE7uHJ+c2cwRgMq5RL3Sy9ayZejmi7aXNp0SBXD8IHXkCQdvwKZkK3h M19nbq2150C6MxdwYd46775p7bxMSPQsbwxiWikKwo/F+lA2KVLAh80AMOTn9eD3kUgX biwJcZe7wGNpO24L4ZbGc6SRoeUeoME/p7sy8Lv/fFNbYng+GxoeMUyZGRWh0vCb03u4 BsPgy0BlgNrMjMVpXAd27ruAM/n4i0RqfATUtlJHyH5/kQdUyhSWTjtc3UAQt6N9/7/5 UgwHBqgvJnxfODrA4o69cpwRYhKI23D1Ajpmi3B75A5J4n9ZA/9Ge3MU+fSAYox50Nii 1qyQ== X-Gm-Message-State: ANhLgQ0xt/yVdr6uwuU51M9drEDl3SsL2M+EzQSROV1u0rfroamrK+9K 0NgGohTeAKRwW1hKKQGD3ebMjA== X-Google-Smtp-Source: ADFU+vtoR2JbFrN0nfJxqDYLP+xTflEVq5wNUz/jOry5OWPekgyUroWOpJkr2awpIEctqkOBklBL7A== X-Received: by 2002:adf:e345:: with SMTP id n5mr490914wrj.220.1585329589373; Fri, 27 Mar 2020 10:19:49 -0700 (PDT) Received: from zen.linaroharston ([51.148.130.216]) by smtp.gmail.com with ESMTPSA id s11sm9434973wrw.58.2020.03.27.10.19.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 27 Mar 2020 10:19:47 -0700 (PDT) Received: from zen (localhost [127.0.0.1]) by zen.linaroharston (Postfix) with ESMTP id 3794A1FF7E; Fri, 27 Mar 2020 17:19:47 +0000 (GMT) References: <20200227113735.23605-1-peter.hilber@opensynergy.com> <20200317192053.15665-1-peter.hilber@opensynergy.com> User-agent: mu4e 1.3.10; emacs 28.0.50 From: Alex =?utf-8?Q?Benn=C3=A9e?= To: Peter Hilber Subject: Re: [virtio-dev] [PATCH v3] Add virtio SCMI device specification In-reply-to: <20200317192053.15665-1-peter.hilber@opensynergy.com> Date: Fri, 27 Mar 2020 17:19:47 +0000 Message-ID: <87369tn2a4.fsf@linaro.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200327_101951_653518_83C16E8C X-CRM114-Status: GOOD ( 11.10 ) 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: virtio-dev@lists.oasis-open.org, Sudeep.Holla@arm.com, Souvik.Chakravarty@arm.com, linux-arm-kernel@lists.infradead.org, virtio-comment@lists.oasis-open.org Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org ClBldGVyIEhpbGJlciA8cGV0ZXIuaGlsYmVyQG9wZW5zeW5lcmd5LmNvbT4gd3JpdGVzOgoKPiBU aGlzIHBhdGNoIHByb3Bvc2VzIGEgbmV3IHZpcnRpbyBkZXZpY2UgZm9yIHRoZSBBcm0gU0NNSSBw cm90b2NvbC4KPgo+IFRoZSBkZXZpY2UgcHJvdmlkZXMgYSBzaW1wbGUgdHJhbnNwb3J0IGZvciB0 aGUgQXJtIFNDTUkgcHJvdG9jb2xbMV0uIFRoZQo+ICpTKnlzdGVtICpDKm9udHJvbCBhbmQgKk0q YW5hZ2VtZW50ICpJKm50ZXJmYWNlIHByb3RvY29sIGFsbG93cyBzcGVha2luZwo+IHRvIHN5c3Rl bSBjb250cm9sbGVycyB0aGF0IGFsbG93IG9yY2hlc3RyYXRpbmcgdGhpbmdzIGxpa2UgcG93ZXIK PiBtYW5hZ2VtZW50LCBzeXN0ZW0gc3RhdGUgbWFuYWdlbWVudCBhbmQgc2Vuc29yIGFjY2Vzcy4g VGhlIFNDTUkgcHJvdG9jb2wKPiBpcyB1c2VkIG9uIFNvQ3Mgd2hlcmUgbXVsdGlwbGUgY29yZXMg YW5kIGNvLXByb2Nlc3NvcnMgbmVlZCBhY2Nlc3MgdG8KPiB0aGVzZSByZXNvdXJjZXMuCj4KPiBU aGUgdmlydGlvIHRyYW5zcG9ydCBhbGxvd3MgbWFraW5nIHVzZSBvZiB0aGlzIHByb3RvY29sIGlu IHZpcnR1YWxpemVkCj4gc3lzdGVtcy4KPgo+IFsxXSBodHRwczovL2RldmVsb3Blci5hcm0uY29t L2RvY3MvZGVuMDA1Ni9iCj4KPiBTaWduZWQtb2ZmLWJ5OiBQZXRlciBIaWxiZXIgPHBldGVyLmhp bGJlckBvcGVuc3luZXJneS5jb20+CjxzbmlwPgo+ICsKPiArXHN1YnN1YnNlY3Rpb257U2hhcmVk IE1lbW9yeSBPcGVyYXRpb259Cj4gKwo+ICtWYXJpb3VzIFNDTUkgcHJvdG9jb2xzIGRlZmluZSBz dGF0aXN0aWNzIHNoYXJlZCBtZW1vcnkgcmVnaW9ucyAoZm9yCj4gK3N0YXRpc3RpY3MgYW5kIHNl bnNvciB2YWx1ZXMpLgo+ICsKPiArXGRldmljZW5vcm1hdGl2ZXtccGFyYWdyYXBofXtTaGFyZWQg TWVtb3J5IE9wZXJhdGlvbn17RGV2aWNlIFR5cGVzIC8gU0NNSSBEZXZpY2UgLyBEZXZpY2UgT3Bl cmF0aW9uIC8gU2hhcmVkIE1lbW9yeSBPcGVyYXRpb259Cj4gKwo+ICtJZiBWSVJUSU9fU0NNSV9G X1NIQVJFRF9NRU1PUlkgd2FzIG5lZ290aWF0ZWQsIHRoZSBkZXZpY2UgTUFZIGltcGxlbWVudAo+ ICthbiBTQ01JIHN0YXRpc3RpY3Mgc2hhcmVkIG1lbW9yeSByZWdpb24gdXNpbmcgYSB2aXJ0aW8g c2hhcmVkIG1lbW9yeQo+ICtyZWdpb24uCgpBRkFJQ1QgdGhpcyBpcyB0aGUgZmlyc3QgdXNhZ2Ug b2Ygc2htaWQgaW4gdGhlIHZpcnRpbyBzcGVjIHNvIEkgaGF2ZQpzb21lIHF1ZXN0aW9ucy4gVGhl IHNwZWMgc2F5czoKCiAgTWVtb3J5IGNvbnNpc3RlbmN5IHJ1bGVzIHZhcnkgZGVwZW5kaW5nIG9u IHRoZSByZWdpb24gYW5kIHRoZSBkZXZpY2UKICBhbmQgdGhleSB3aWxsIGJlIHNwZWNpZmllZCBh cyByZXF1aXJlZCBieSBlYWNoIGRldmljZS4KClNvIHdoYXQgYXJlIHRoZSBydWxlcyBmb3IgbWVt b3J5IGNvbnNpc3RlbmN5IGZvciB0aGVzZSByZWdpb25zOgoKICAtIGFyZSB0aGV5IHJlYWQtb25s eSB3LnIudCB0aGUgZ3Vlc3Q/IChtYXliZSB0aGlzIGlzIGltcGxpY2l0PykKICAtIGhvdyBkb2Vz IHRoZSBndWVzdCBrbm93IHdoZW4gdGhleSBoYXZlIGJlZW4gdXBkYXRlZD8KICAtIGhvdyBnb2Vz IHRoZSBndWVzdCBrbm93IGl0IGhhc24ndCByZWFkIGEgdmFsdWUgbWlkLXVwZGF0ZT8KCj4gKwo+ ICtJZiB0aGUgZGV2aWNlIGltcGxlbWVudHMgYSBzaGFyZWQgbWVtb3J5IHJlZ2lvbiwgdGhlIGRl dmljZSBNVVNUIGFzc2lnbgo+ICt0aGUgY29ycmVzcG9uZGluZyBzaG1pZCBhcyBwZXIgdGhlIGZv bGxvd2luZyB0YWJsZToKPiArCj4gK1xiZWdpbnt0YWJ1bGFyfXt8bHxsfH0KPiArXGhsaW5lCj4g K1NDTUkgc3RhdGlzdGljcyBzaGFyZWQgbWVtb3J5IHJlZ2lvbiAmIFZpcnRpbyBzaG1pZCBcXAo+ ICtcaGxpbmUgXGhsaW5lCj4gK1Bvd2VyIHN0YXRlIHN0YXRpc3RpY3Mgc2hhcmVkIG1lbW9yeSBy ZWdpb24gJiAxIFxcCj4gK1xobGluZQo+ICtQZXJmb3JtYW5jZSBkb21haW4gc3RhdGlzdGljcyBz aGFyZWQgbWVtb3J5IHJlZ2lvbiAmIDIgXFwKPiArXGhsaW5lCj4gK1NlbnNvciBWYWx1ZXMgU2hh cmVkIE1lbW9yeSAmIDMgXFwKPiArXGhsaW5lCj4gK1Jlc2VydmVkIGZvciBmdXR1cmUgdXNlICYg NCB0byAweDdGIFxcCj4gK1xobGluZQo+ICtWZW5kb3Itc3BlY2lmaWMgc3RhdGlzdGljcyBzaGFy ZWQgbWVtb3J5IHJlZ2lvbnMgJiAweDgwIHRvIDB4RkYgXFwKPiArXGhsaW5lCj4gK1Jlc2VydmVk IGZvciBmdXR1cmUgdXNlICYgMHgxMDAgYW5kIGdyZWF0ZXIgXFwKPiArXGhsaW5lCj4gK1xlbmR7 dGFidWxhcn0KCgotLSAKQWxleCBCZW5uw6llCgpfX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fXwpsaW51eC1hcm0ta2VybmVsIG1haWxpbmcgbGlzdApsaW51eC1h cm0ta2VybmVsQGxpc3RzLmluZnJhZGVhZC5vcmcKaHR0cDovL2xpc3RzLmluZnJhZGVhZC5vcmcv bWFpbG1hbi9saXN0aW5mby9saW51eC1hcm0ta2VybmVsCg==