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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3F3BC07E9D for ; Sat, 24 Sep 2022 06:46:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232550AbiIXGqu (ORCPT ); Sat, 24 Sep 2022 02:46:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47840 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229573AbiIXGqt (ORCPT ); Sat, 24 Sep 2022 02:46:49 -0400 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C30B25FE9; Fri, 23 Sep 2022 23:46:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1664002008; x=1695538008; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=9xhmRG95Oai0Gh6KQQh9QF7sHwJ15jrKdlIwr7wHUek=; b=nu6Qpp3WxFDXHq199aS7hdslYPd09GcSRdptyZumqiAPXqkehsh10PaL NykJ3GBu316DyXtXumEIQBXLFiAB3R8QIyWZ99HCIilpwoXFxhppmfXaW ARbMH4POT+qBO3VlanLYPCjUmtB6UwTYza3eXlyCma3r2dDR+cDoMWeSI CPNEcI2b2wZxqruZvEEr2eqLKYHN2TlNXufUFGtOrglcOpkhG7W9f2EhW Ompon42Mj/940jsNIjYAwAzeJtyeeqsgLjM44KzFIFUy+Kat1Ru78o7ev ZXoGn2VnLM34xf7QYJzotGQ5Ql1IDXMRqXFI3aJaagaF/2qiKTaUbTO8U Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10479"; a="302206542" X-IronPort-AV: E=Sophos;i="5.93,341,1654585200"; d="scan'208";a="302206542" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Sep 2022 23:46:48 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.93,341,1654585200"; d="scan'208";a="622767116" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga007.fm.intel.com with ESMTP; 23 Sep 2022 23:46:45 -0700 Received: by black.fi.intel.com (Postfix, from userid 1001) id A9FE9F7; Sat, 24 Sep 2022 09:47:03 +0300 (EEST) Date: Sat, 24 Sep 2022 09:47:03 +0300 From: Mika Westerberg To: Mario Limonciello Cc: Andreas Noever , Michael Jamet , Yehezkel Bernat , Mehta Sanju , stable@vger.kernel.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3] thunderbolt: Explicitly enable lane adapter hotplug events at startup Message-ID: References: <20220923183944.10746-1-mario.limonciello@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220923183944.10746-1-mario.limonciello@amd.com> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Hi Mario, On Fri, Sep 23, 2022 at 01:39:44PM -0500, Mario Limonciello wrote: > Software that has run before the USB4 CM in Linux runs may have disabled > hotplug events for a given lane adapter. > > Other CMs such as that one distributed with Windows 11 will enable hotplug > events. Do the same thing in the Linux CM which fixes hotplug events on > "AMD Pink Sardine". > > Cc: stable@vger.kernel.org > Signed-off-by: Mario Limonciello > --- > v2->v3: > * Guard with tb_switch_is_icm to avoid risk to Intel FW CM case > v1->v2: > * s/usb4_enable_hotplug/usb4_port_hotplug_enable/ > * Clarify intended users in documentation comment > * Only call for lane adapters > * Add stable tag > > Note: v2 it was suggested to move this to tb_switch_configure, but > port->config is not yet read at that time. This should be the right > time to call it, so this version of the patch just guards against the > code running on Intel's controllers that have a FW CM. Can we put it in a separate function that is called from tb_switch_add()? I explained in the previous reply (to v2) that the tb_init_port() is pretty much just reading stuff and therefore I would not like to add there anything that does writing. While at it, the USB4 v2 spec (not yet public but can be found from the working group site) adds a CM requirement that forbids writing lane 1 adapter configuration registers so in addition to that please check port->cap_usb4 there so we know we deal with the lane 0 adapter only (as ->cap_usb4 is only set for the lane 0 adapters). So something like this: static void tb_switch_port_hotplug_enable(struct tb_switch *sw) { if (tb_switch_is_icm(sw)) return; tb_switch_for_each_port(sw, port) { if (!port->cap_usb4) continue; // here enable the hotplug } } int tb_switch_add(struct tb_switch *sw) { ... // init ports and stuff happens here tb_switch_default_link_ports(sw); tb_switch_port_hotplug_enable(sw); } (we should probably create a new macro tb_switch_for_each_usb4_port() that just enumerates all USB4 ports).