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 Received: from ws5-mx01.kavi.com (ws5-mx01.kavi.com [34.193.7.191]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 03886C4167B for ; Mon, 4 Dec 2023 09:41:34 +0000 (UTC) Received: from lists.oasis-open.org (oasis.ws5.connectedcommunity.org [10.110.1.242]) by ws5-mx01.kavi.com (Postfix) with ESMTP id 4134F2CADD for ; Mon, 4 Dec 2023 09:41:34 +0000 (UTC) Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 226939863F0 for ; Mon, 4 Dec 2023 09:41:34 +0000 (UTC) Received: from host09.ws5.connectedcommunity.org (host09.ws5.connectedcommunity.org [10.110.1.97]) by lists.oasis-open.org (Postfix) with QMQP id 041A798408C; Mon, 4 Dec 2023 09:41:34 +0000 (UTC) Mailing-List: contact virtio-dev-help@lists.oasis-open.org; run by ezmlm List-ID: Sender: Precedence: bulk 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 E6EFD986377 for ; Mon, 4 Dec 2023 09:41:33 +0000 (UTC) X-Virus-Scanned: amavisd-new at kavi.com X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701682892; x=1702287692; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=fHYsh7OmxZQezOX7dfGh7Q9lPmJ2X1k3LnlsEPSJZwM=; b=BlYV9btC292N7a4zDMU2+nNxEH988JqrSXWQhPO8lGtb+kmMihBwardS9hG1dALHJ8 D7MszgZIwd6iN/mlQY6ZTFvgsZuP1TN9WqVmiXTBDk04FDEQrAvRwvDMLFJGxJnHzX4U UpgEHwKhvQVrARJiBEfB4KjkaxrgmKnfLkOr9wWn8DVLd7g6jpi7BdU+rb+jZjOsBvl1 tjjk/Dlk30cKtza3ip9n9zLDPoce8Z4yBnT103vK/QMooiYfrbB/oTUwPLQf93t0UJEA lxA8fSmVIvKozguYxhHK4G44959VIa2qnqihqja7gZxBt7ew5EsYCKgwi263V54OZvut xDDQ== X-Gm-Message-State: AOJu0YyTusWB593v+S6GAYx9UaX3MDHxpZttuc+kaC9F6NGzvQjG81Gg pAOBzN74rKhuo6Jo5MLXD8dDzA== X-Google-Smtp-Source: AGHT+IGIEI4bip3e8piTzZqoMd8OgbN+NjU8eQxeMZaml0g985zyVZ9DXfpIRXfgMythZ1JCcu4jfg== X-Received: by 2002:a05:6a20:7d8f:b0:18c:8ff1:f0b with SMTP id v15-20020a056a207d8f00b0018c8ff10f0bmr2035975pzj.56.1701682892235; Mon, 04 Dec 2023 01:41:32 -0800 (PST) From: David Stevens To: "Michael S . Tsirkin" , virtio-comment@lists.oasis-open.org, virtio-dev@lists.oasis-open.org Cc: David Stevens Date: Mon, 4 Dec 2023 18:41:22 +0900 Message-ID: <20231204094123.856214-1-stevensd@chromium.org> X-Mailer: git-send-email 2.43.0.rc2.451.g8631bc7472-goog MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [virtio-dev] [PATCH v3 0/1] Define low power mode for devices The virtio spec currently does not include the concept of device power management. The lack means that there is no good action drivers can take when they are requested to put the device into a low power state (e.g. when a guest is entering a system-wide low power state like S0ix/S3). Stateless devices can be handled - albeit inefficiently - by resetting and reinitialzing the device. However, stateful devices cannot support this situation. This patch defines a low power mode for devices that can be used in this situation. Low power mode is mostly defined at the transport layer, and all device-side power optimizations are optional. This avoids the need for invasive device-by-device definitions. It also pushes the requirement onto the device side, to simplify what driver side changes are necessary to just [1]. I believe this patch may address the virtio-gpu issue which [2] is trying to address by avoiding the reset altogether when the guest enters S3. [1] https://lore.kernel.org/lkml/20231113055138.117392-1-stevensd@chromium.org/ [2] https://lore.kernel.org/lkml/20230919114242.2283646-1-Jiqian.Chen@amd.com/ v2 -> v3: - Use different words for some concepts to avoid conflicts with other parts of the spec. - Rewrite various sentences to improve clarity. v1 -> v2: - Define virtio-pci support on top of PCI power management. - Add more conformance requirements. David Stevens (1): Define a low power mode for devices content.tex | 61 +++++++++++++++++++++++++++++++++++++++++++++++ transport-pci.tex | 9 +++++++ 2 files changed, 70 insertions(+) -- 2.43.0.rc2.451.g8631bc7472-goog --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org