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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 48D2DECE587 for ; Tue, 1 Oct 2019 12:49:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 171C82190F for ; Tue, 1 Oct 2019 12:49:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569934199; bh=tGW212EaZmrIn29aaNmsRxwukQPltuKjXALvxdLiSqs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=t1UhsbjzEeEm385dMFQzvo50JkewNBBFjRHwNJjoYIrkEhAZ48CebatmIyQKJsmGm gRyPvF18yNhdY2P4Nhyn1rPTyvjpaPE3IcPMdQwvlPhlP1aHFJcqUlB+naTSDwTH85 TPQ3apsRuQ8Oh6E/xKqLvsx3XTWh55TBihCHi49o= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388056AbfJAMt6 (ORCPT ); Tue, 1 Oct 2019 08:49:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:42196 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725821AbfJAMt5 (ORCPT ); Tue, 1 Oct 2019 08:49:57 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7160C21872; Tue, 1 Oct 2019 12:49:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569934197; bh=tGW212EaZmrIn29aaNmsRxwukQPltuKjXALvxdLiSqs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qMuMSnOFckB43S5qaHlnoK/36P6/h3jdTZTwaFWd3frHjaQGai/xTS/gzELxjtUk2 Rpu1UjpzbrecweumHflFu49IPS6+ih3Xnjkdt4mK9lJHvkbCkvMl2QRxd/ldD1kmef 7OCHDEgtKzSsCuItX8L5/YHlSEPeygv67jfLkQRE= Date: Tue, 1 Oct 2019 14:49:54 +0200 From: Greg Kroah-Hartman To: Mika Westerberg Cc: linux-usb@vger.kernel.org, Andreas Noever , Michael Jamet , Yehezkel Bernat , Rajmohan Mani , Nicholas Johnson , Lukas Wunner , Alan Stern , Mario.Limonciello@dell.com, Anthony Wong , linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH 00/22] thunderbolt: Add support for USB4 Message-ID: <20191001124954.GI2954373@kroah.com> References: <20191001113830.13028-1-mika.westerberg@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191001113830.13028-1-mika.westerberg@linux.intel.com> User-Agent: Mutt/1.12.2 (2019-09-21) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 01, 2019 at 02:38:08PM +0300, Mika Westerberg wrote: > Hi all, > > I'm sending this as RFC because the series is still missing important > features such as power management so not ready for merging. However, I > think it is good to get any early feedback from the community. We are > working to add support for the missing features. > > USB4 is the public specification of Thunderbolt 3 protocol and can be > downloaded here: > > https://www.usb.org/sites/default/files/USB4%20Specification_1.zip > > USB4 is about tunneling different protocols over a single cable (in the > same way as Thunderbolt). The current USB4 spec supports PCIe, Display Port > and USB 3.x, and also software based protocols such as networking between > domains (hosts). > > So far PCs have been using firmware based Connection Manager and Apple > systems have been using software based one. A Connection Manager is the > entity that handles creation of different tunnel types through the USB4 > (and Thunderbolt) fabric. With USB4 the plan is to have software based > Connection Manager everywhere but some early systems will also support > firmware to allow OS downgrade for example. > > Current Linux Thunderbolt driver supports both "modes" and can detect which > one to use dynamically. > > This series first adds support for Thunderbolt 3 devices to the software > connection manager and then extends that to support USB4 compliant hosts > and devices (this applies to both firmware and software based connection > managers). With this series the following features are supported also for > USB4 compliant devices: > > - PCIe tunneling > - Display Port tunneling > - USB 3.x tunneling > - P2P networking (implemented in drivers/net/thunderbolt.c) > - Host and device NVM firmware upgrade > > We also add two new sysfs attributes under each device that expose link > speed and width to userspace. The rest of the userspace ABI stays the same. > > I'm including Linux USB folks as well because USB4 is officially coming > from USB-IF which puts us on same boat now. > > While I changed the user visible Kconfig string to mention "USB4" (the > Kconfig option is still CONFIG_THUNDERBOLT), I'm wondering whether we > should move the whole Thunderbolt driver under drivers/usb/thunderbolt as > well? Looks "interesting", nice work! I stopped at patch "Add initial support for USB4" as I don't think we want to add USB4 code to a system that we know does not have it, right? Everything up to then is just "normal" thunderbolt, and with the exception of a few minor comments, all look fine to me. I didn't actually read the USB4 patch just yet, as I figured we needed to argue about that some more :) thanks, greg k-h