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=-4.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 F22B7C433E6 for ; Thu, 21 Jan 2021 16:45:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A51A423A3C for ; Thu, 21 Jan 2021 16:45:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731917AbhAUQou (ORCPT ); Thu, 21 Jan 2021 11:44:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52550 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733194AbhAUQj0 (ORCPT ); Thu, 21 Jan 2021 11:39:26 -0500 Received: from mail-oi1-x235.google.com (mail-oi1-x235.google.com [IPv6:2607:f8b0:4864:20::235]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A0970C061756 for ; Thu, 21 Jan 2021 08:38:43 -0800 (PST) Received: by mail-oi1-x235.google.com with SMTP id q205so2713769oig.13 for ; Thu, 21 Jan 2021 08:38:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=vgJVNcBk/J2Fk5eOL9Xgg6j8k4zlRMwcU+kChAqOVec=; b=CqmRrTUd1Yfr2hf7RTFpKP0/fuWiO4yDOaBFuNdz/AVpQcG78QSXI6TCJ0P/36FoO/ AKMC/FSBYQH+HCR30tI6JdMdqfuedcUaFVyOujDomQ6HoMukpuh0X1rYVzQTEL6nzYSh GkAnuExWVIRy30WK+0Pi2YJb0HMyDkdMf27A5Lv/VIeCODGfXAEjOKavsPti5t0QbEu3 Vau1ygrqlKrfptANJwE9PekrtazQVlwN0xV4xjsFEFX1VPBk3AGQfm1yDRR6hY9PpdAQ kwAMjkFtbNOonVpgywVc56RY7qiLrjsiHsdOsaE+je2IxOf3pPIzkyN228AgbLFN5KOb v0ag== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=vgJVNcBk/J2Fk5eOL9Xgg6j8k4zlRMwcU+kChAqOVec=; b=GRD9WpYBXh6KzHKASCnrgqWLZVLwYqahxJkohvpr7qe1bBtpW6NOJ2J3E9LGamZiVx bpCGSLvlT3KX10nOv+y+EeaKPcp05e0nsYDxXEGDP5HeLhye25GI/DLdjNr7FQ9zv/w8 jzlkqR6X8iabBLMnxpEJn2jqsyaIyRoJfpmQKnRg5K1jaTYLgMENniIy4p8BwiszcbvQ /kSRSLWdk0V4fCvVhORp8KMn4fZ8CgPOX9RBHefTiJmMyvhYzn5Hprw7+FRFdVfJzRws lNHrhjJ7bQLRd929o5kdCH2pBLw9S8mn6x5Iw+N76ayJa+qiAKp/bjvBhKvFoMVYvSR5 lmlQ== X-Gm-Message-State: AOAM533Wh+RXIQx39YR6uLHn6UOew+I32lFYnBrluadgGll4riOpxvFw K9YZb4ueryaRcYELxQnPfTo= X-Google-Smtp-Source: ABdhPJyH2VGRtIp//DNPTAyzDHXeKdsAp24fg8H82wWDbEDvDEQup2f2eTICBNYCRj1HvtglFjcZOg== X-Received: by 2002:a05:6808:69a:: with SMTP id k26mr265418oig.115.1611247123140; Thu, 21 Jan 2021 08:38:43 -0800 (PST) Received: from Davids-MacBook-Pro.local ([8.48.134.50]) by smtp.googlemail.com with ESMTPSA id e205sm1130564oia.16.2021.01.21.08.38.41 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 21 Jan 2021 08:38:42 -0800 (PST) Subject: Re: [patch net-next RFC 00/10] introduce line card support for modular switch To: Jiri Pirko , Jakub Kicinski Cc: Andrew Lunn , netdev@vger.kernel.org, davem@davemloft.net, jacob.e.keller@intel.com, roopa@nvidia.com, mlxsw@nvidia.com References: <20210113121222.733517-1-jiri@resnulli.us> <20210119115610.GZ3565223@nanopsycho.orion> <20210120083605.GB3565223@nanopsycho.orion> <20210120154158.206b8752@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <20210121153224.GE3565223@nanopsycho.orion> From: David Ahern Message-ID: <971e9eff-0b71-8ff9-d72c-aebe73cab599@gmail.com> Date: Thu, 21 Jan 2021 09:38:40 -0700 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.16; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 MIME-Version: 1.0 In-Reply-To: <20210121153224.GE3565223@nanopsycho.orion> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 1/21/21 8:32 AM, Jiri Pirko wrote: > Thu, Jan 21, 2021 at 12:41:58AM CET, kuba@kernel.org wrote: >> On Wed, 20 Jan 2021 14:56:46 +0100 Andrew Lunn wrote: >>>> No, the FW does not know. The ASIC is not physically able to get the >>>> linecard type. Yes, it is odd, I agree. The linecard type is known to >>>> the driver which operates on i2c. This driver takes care of power >>>> management of the linecard, among other tasks. >>> >>> So what does activated actually mean for your hardware? It seems to >>> mean something like: Some random card has been plugged in, we have no >>> idea what, but it has power, and we have enabled the MACs as >>> provisioned, which if you are lucky might match the hardware? >>> >>> The foundations of this feature seems dubious. >> >> But Jiri also says "The linecard type is known to the driver which >> operates on i2c." which sounds like there is some i2c driver (in user >> space?) which talks to the card and _does_ have the info? Maybe I'm >> misreading it. What's the i2c driver? > > That is Vadim's i2c kernel driver, this is going to upstream. > This pre-provisioning concept makes a fragile design to work around h/w shortcomings. You really need a way for the management card to know exactly what was plugged in to a slot so the control plane S/W can respond accordingly. Surely there is a way for processes on the LC to communicate with a process on the management card - even if it is inband packets with special headers.