From patchwork Wed Dec 9 07:29:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Saeed Mahameed X-Patchwork-Id: 1413228 Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4CrTK00GNyz9sWP for ; Wed, 9 Dec 2020 18:32:20 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727975AbgLIHb4 (ORCPT ); Wed, 9 Dec 2020 02:31:56 -0500 Received: from mail.kernel.org ([198.145.29.99]:60634 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727857AbgLIHbn (ORCPT ); Wed, 9 Dec 2020 02:31:43 -0500 From: saeed@kernel.org Authentication-Results: mail.kernel.org; dkim=permerror (bad message/signature format) To: "David S. Miller" , Jakub Kicinski , Jason Gunthorpe Cc: Leon Romanovsky , netdev@vger.kernel.org, linux-rdma@vger.kernel.org, David Ahern , Jacob Keller , Sridhar Samudrala , david.m.ertman@intel.com, dan.j.williams@intel.com, kiran.patil@intel.com, gregkh@linuxfoundation.org, Parav Pandit , Jiri Pirko , Saeed Mahameed Subject: [PATCH net-next v2 12/14] devlink: Add devlink port documentation Date: Tue, 8 Dec 2020 23:29:32 -0800 Message-Id: <20201209072934.1272819-13-saeed@kernel.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201209072934.1272819-1-saeed@kernel.org> References: <20201209072934.1272819-1-saeed@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Parav Pandit Added documentation for devlink port and port function related commands. Signed-off-by: Parav Pandit Reviewed-by: Jiri Pirko Reviewed-by: Jacob Keller Signed-off-by: Saeed Mahameed --- Changelog: v5->v6: - added label for devlink port to refer in other documentation - rephrased port flavour description - added article a before "PCI device" - changed 'root complex' to 'root complexes' - changed 'may support' to 'support' - rephrased diagram description line - removed networking from port flavour description v4->v5: - described logically ingress and egress point of devlink port - removed networking from devlink port description - rephrased port type description - introduce PCI controller section and description - rephrased controller, device, function description - removed confusing eswitch to system wording - rephrased port function description - added example of mac address in port function attribute description v3->v4: - changed 'exist' to 'exists' - added 'an' eswitch - changed 'can have one' to 'consists of' - changed 'who intents' to 'that intends' - removed unnecessary comma - rewrote description for the example diagram - changed 'controller consist of' to 'controller consists of' v2->v3: - rephrased many lines - first paragraph now describe devlink port - instead of saying PCI device/function, using PCI function every where - changed 'physical link layer' to 'link layer' - made devlink port type description more clear - made devlink port flavour description more clear - moved devlink port type table after port flavour - added description for the example diagram - describe CPU port that its linked to DSA - made devlink port description for eswitch port more clear v1->v2: - Removed duplicate table entries for DEVLINK_PORT_FLAVOUR_VIRTUAL. - replaced 'consist of' to 'consisting' - changed 'can be' to 'can be of' --- .../networking/devlink/devlink-port.rst | 118 ++++++++++++++++++ Documentation/networking/devlink/index.rst | 1 + 2 files changed, 119 insertions(+) create mode 100644 Documentation/networking/devlink/devlink-port.rst diff --git a/Documentation/networking/devlink/devlink-port.rst b/Documentation/networking/devlink/devlink-port.rst new file mode 100644 index 000000000000..4c910dbb01ca --- /dev/null +++ b/Documentation/networking/devlink/devlink-port.rst @@ -0,0 +1,118 @@ +.. SPDX-License-Identifier: GPL-2.0 + +.. _devlink_port: + +============ +Devlink Port +============ + +``devlink-port`` is a port that exists on the device. It has a logically +separate ingress/egress point of the device. A devlink port can be any one +of many flavours. A devlink port flavour along with port attributes +describe what a port represents. + +A device driver that intends to publish a devlink port sets the +devlink port attributes and registers the devlink port. + +Devlink port flavours are described below. + +.. list-table:: List of devlink port flavours + :widths: 33 90 + + * - Flavour + - Description + * - ``DEVLINK_PORT_FLAVOUR_PHYSICAL`` + - Any kind of physical port. This can be an eswitch physical port or any + other physical port on the device. + * - ``DEVLINK_PORT_FLAVOUR_DSA`` + - This indicates a DSA interconnect port. + * - ``DEVLINK_PORT_FLAVOUR_CPU`` + - This indicates a CPU port applicable only to DSA. + * - ``DEVLINK_PORT_FLAVOUR_PCI_PF`` + - This indicates an eswitch port representing a port of PCI + physical function (PF). + * - ``DEVLINK_PORT_FLAVOUR_PCI_VF`` + - This indicates an eswitch port representing a port of PCI + virtual function (VF). + * - ``DEVLINK_PORT_FLAVOUR_VIRTUAL`` + - This indicates a virtual port for the PCI virtual function. + +Devlink port can have a different type based on the link layer described below. + +.. list-table:: List of devlink port types + :widths: 23 90 + + * - Type + - Description + * - ``DEVLINK_PORT_TYPE_ETH`` + - Driver should set this port type when a link layer of the port is + Ethernet. + * - ``DEVLINK_PORT_TYPE_IB`` + - Driver should set this port type when a link layer of the port is + InfiniBand. + * - ``DEVLINK_PORT_TYPE_AUTO`` + - This type is indicated by the user when driver should detect the port + type automatically. + +PCI controllers +--------------- +In most cases a PCI device has only one controller. A controller consists of +potentially multiple physical and virtual functions. Such PCI function consists +of one or more ports. This port of the function is represented by the devlink +eswitch port. + +A PCI Device connected to multiple CPUs or multiple PCI root complexes or +SmartNIC, however, may have multiple controllers. For a device with multiple +controllers, each controller is distinguished by a unique controller number. +An eswitch on the PCI device support ports of multiple controllers. + +An example view of a system with two controllers:: + + --------------------------------------------------------- + | | + | --------- --------- ------- ------- | + ----------- | | vf(s) | | sf(s) | |vf(s)| |sf(s)| | + | server | | ------- ----/---- ---/----- ------- ---/--- ---/--- | + | pci rc |=== | pf0 |______/________/ | pf1 |___/_______/ | + | connect | | ------- ------- | + ----------- | | controller_num=1 (no eswitch) | + ------|-------------------------------------------------- + (internal wire) + | + --------------------------------------------------------- + | devlink eswitch ports and reps | + | ----------------------------------------------------- | + | |ctrl-0 | ctrl-0 | ctrl-0 | ctrl-0 | ctrl-0 |ctrl-0 | | + | |pf0 | pf0vfN | pf0sfN | pf1 | pf1vfN |pf1sfN | | + | ----------------------------------------------------- | + | |ctrl-1 | ctrl-1 | ctrl-1 | ctrl-1 | ctrl-1 |ctrl-1 | | + | |pf0 | pf0vfN | pf0sfN | pf1 | pf1vfN |pf1sfN | | + | ----------------------------------------------------- | + | | + | | + ----------- | --------- --------- ------- ------- | + | smartNIC| | | vf(s) | | sf(s) | |vf(s)| |sf(s)| | + | pci rc |==| ------- ----/---- ---/----- ------- ---/--- ---/--- | + | connect | | | pf0 |______/________/ | pf1 |___/_______/ | + ----------- | ------- ------- | + | | + | local controller_num=0 (eswitch) | + --------------------------------------------------------- + +In above example, external controller (identified by controller number = 1) +doesn't have eswitch. Local controller (identified by controller number = 0) +has the eswitch. Devlink instance on local controller has eswitch devlink +ports representing ports for both the controllers. + +Port function configuration +=========================== + +A user can configure the port function attribute before enumerating the +PCI function. Usually it means, user should configure port function attribute +before a bus specific device for the function is created. However, when +SRIOV is enabled, virtual function devices are created on the PCI bus. +Hence, function attribute should be configured before binding virtual +function device to the driver. + +User may set the hardware address of the function represented by the devlink +port function. For Ethernet port function this means a MAC address. diff --git a/Documentation/networking/devlink/index.rst b/Documentation/networking/devlink/index.rst index d82874760ae2..aab79667f97b 100644 --- a/Documentation/networking/devlink/index.rst +++ b/Documentation/networking/devlink/index.rst @@ -18,6 +18,7 @@ general. devlink-info devlink-flash devlink-params + devlink-port devlink-region devlink-resource devlink-reload