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=-11.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 0E98EC4338F for ; Wed, 18 Aug 2021 15:52:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D92D4610CE for ; Wed, 18 Aug 2021 15:52:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238409AbhHRPxN (ORCPT ); Wed, 18 Aug 2021 11:53:13 -0400 Received: from new1-smtp.messagingengine.com ([66.111.4.221]:60205 "EHLO new1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240157AbhHRPxL (ORCPT ); Wed, 18 Aug 2021 11:53:11 -0400 Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailnew.nyi.internal (Postfix) with ESMTP id 84337582FD7; Wed, 18 Aug 2021 11:52:36 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute3.internal (MEProxy); Wed, 18 Aug 2021 11:52:36 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:date:from :message-id:mime-version:subject:to:x-me-proxy:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm3; bh=/qZ7p/hKU3x329mOF TRhmrSc7atMRbtFSYwTM5AGPIQ=; b=HOCaCXuEqqxhTQGdbiQ6a9KZT/SB4+oog bbezZBkokp4R/qmMl3cplz+MUct9a+48of3kvSeeYaGu4KUmzPCikIGlxZ/2FUWT o1OewfYbQRdNQ83um+iLJ34OX15oan3xO9UdGYlCy1WiDQgISKSEQCCpZqcdxH+c Ks0bg/yOzNdOSXNk61u6dg73tzdJlWnuP5uCRrjUAOe1BzI9dz5zK0xeBSHpYvu6 nbIvM7vua4UxGpFPgP3gqnRe01bYE3If9Uyzo5+ei0hpnBqGsK5hEj3JynuqDAE9 JtW8ZxG1sIrXLEaY2jRGkDxfSQvG3tB73H40i1BQAV3YSrnl0q34w== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvtddrleehgdelvdcutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecunecujfgurhephffvufffkffoggfgsedtkeertdertd dtnecuhfhrohhmpefkughoucfutghhihhmmhgvlhcuoehiughoshgthhesihguohhstghh rdhorhhgqeenucggtffrrghtthgvrhhnpeeukeeggfegkeekleefledtheevkedtveekge dthfdukeetgfeghfefleelfeelffenucffohhmrghinhepkhgvrhhnvghlrdhorhhgpdhs nhhirgdrohhrghdpqhhsfhhpqdguugdrtghomhenucevlhhushhtvghrufhiiigvpedtne curfgrrhgrmhepmhgrihhlfhhrohhmpehiughoshgthhesihguohhstghhrdhorhhg X-ME-Proxy: Received: by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 18 Aug 2021 11:52:32 -0400 (EDT) From: Ido Schimmel To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, andrew@lunn.ch, mkubecek@suse.cz, pali@kernel.org, jacob.e.keller@intel.com, jiri@nvidia.com, vadimp@nvidia.com, mlxsw@nvidia.com, Ido Schimmel Subject: [RFC PATCH net-next v2 0/6] ethtool: Add ability to control transceiver modules' power mode Date: Wed, 18 Aug 2021 18:51:56 +0300 Message-Id: <20210818155202.1278177-1-idosch@idosch.org> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Ido Schimmel This patchset extends the ethtool netlink API to allow user space to control transceiver modules. Two specific APIs are added, but the plan is to extend the interface with more APIs in the future (see "Future plans"). This submission is a complete rework of a previous submission [1] that tried to achieve the same goal by allowing user space to write to the EEPROMs of these modules. It was rejected as it could have enabled user space binary blob drivers. However, the main issue is that by directly writing to some pages of these EEPROMs, we are interfering with the entity that is controlling the modules (kernel / device firmware). In addition, some functionality cannot be implemented solely by writing to the EEPROM, as it requires the assertion / de-assertion of hardware signals (e.g., "ResetL" pin in SFF-8636). Motivation ========== The kernel can currently dump the contents of module EEPROMs to user space via the ethtool legacy ioctl API or the new netlink API. These dumps can then be parsed by ethtool(8) according to the specification that defines the memory map of the EEPROM. For example, SFF-8636 [2] for QSFP and CMIS [3] for QSFP-DD. In addition to read-only elements, these specifications also define writeable elements that can be used to control the behavior of the module. For example, controlling whether the module is put in low or high power mode to limit its power consumption. The CMIS specification even defines a message exchange mechanism (CDB, Command Data Block) on top of the module's memory map. This allows the host to send various commands to the module. For example, to update its firmware. Implementation ============== The ethtool netlink API is extended with two new messages, 'ETHTOOL_MSG_MODULE_SET' and 'ETHTOOL_MSG_MODULE_GET', that allow user space to set and get transceiver module parameters. Specifically, the 'ETHTOOL_A_MODULE_POWER_MODE_POLICY' attribute allows user space to control the power mode policy of the module in order to limit its power consumption. See detailed description in patch #1. The user API is designed to be generic enough so that it could be used for modules with different memory maps (e.g., SFF-8636, CMIS). The only implementation of the device driver API in this series is for a MAC driver (mlxsw) where the module is controlled by the device's firmware, but it is designed to be generic enough so that it could also be used by implementations where the module is controlled by the kernel. Testing and introspection ========================= See detailed description in patches #1 and #5. Patchset overview ================= Patch #1 adds the initial infrastructure in ethtool along with the ability to control transceiver modules' power mode. Patches #2-#3 add required device registers in mlxsw. Patch #4 implements in mlxsw the ethtool operations added in patch #1. Patch #5 adds extended link states in order to allow user space to troubleshoot link down issues related to transceiver modules. Patch #6 adds support for these extended states in mlxsw. Future plans ============ * Extend 'ETHTOOL_MSG_MODULE_SET' to control Tx output among other attributes. * Add new ethtool message(s) to update firmware on transceiver modules. * Extend ethtool(8) to parse more diagnostic information from CMIS modules. No kernel changes required. Changes since RFC v1 [4]: * Split 'ETHTOOL_A_MODULE_LOW_POWER_ENABLED' into two attributes. * Add 'high-on-up' power mode policy. * Drop 'ETHTOOL_MSG_MODULE_RESET_ACT' in favor of existing ioctl interface. * Add extended link states to help in troubleshooting. Note: This series does not apply to net-next (it is RFC, anyway) because I left out mundane infra work in mlxsw. Will submit it with reset support as part of a separate set. [1] https://lore.kernel.org/netdev/20210623075925.2610908-1-idosch@idosch.org/ [2] https://members.snia.org/document/dl/26418 [3] http://www.qsfp-dd.com/wp-content/uploads/2021/05/CMIS5p0.pdf [4] https://lore.kernel.org/netdev/20210809102152.719961-1-idosch@idosch.org/ Ido Schimmel (6): ethtool: Add ability to control transceiver modules' power mode mlxsw: reg: Add Port Module Memory Map Properties register mlxsw: reg: Add Management Cable IO and Notifications register mlxsw: Add ability to control transceiver modules' power mode ethtool: Add transceiver module extended states mlxsw: Add support for transceiver module extended states Documentation/networking/ethtool-netlink.rst | 78 ++++++- .../net/ethernet/mellanox/mlxsw/core_env.c | 193 +++++++++++++++++- .../net/ethernet/mellanox/mlxsw/core_env.h | 10 + drivers/net/ethernet/mellanox/mlxsw/minimal.c | 26 +++ drivers/net/ethernet/mellanox/mlxsw/reg.h | 78 +++++++ .../mellanox/mlxsw/spectrum_ethtool.c | 73 ++++++- include/linux/ethtool.h | 26 +++ include/uapi/linux/ethtool.h | 32 +++ include/uapi/linux/ethtool_netlink.h | 17 ++ net/ethtool/Makefile | 2 +- net/ethtool/module.c | 191 +++++++++++++++++ net/ethtool/netlink.c | 19 ++ net/ethtool/netlink.h | 4 + 13 files changed, 741 insertions(+), 8 deletions(-) create mode 100644 net/ethtool/module.c -- 2.31.1