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=-5.2 required=3.0 tests=BAYES_00, 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 9E814C433DF for ; Thu, 20 Aug 2020 08:16:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6A952208DB for ; Thu, 20 Aug 2020 08:16:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726793AbgHTIQp (ORCPT ); Thu, 20 Aug 2020 04:16:45 -0400 Received: from bmailout1.hostsharing.net ([83.223.95.100]:36653 "EHLO bmailout1.hostsharing.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725824AbgHTINW (ORCPT ); Thu, 20 Aug 2020 04:13:22 -0400 Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "*.hostsharing.net", Issuer "COMODO RSA Domain Validation Secure Server CA" (not verified)) by bmailout1.hostsharing.net (Postfix) with ESMTPS id 4566C30000CCE; Thu, 20 Aug 2020 10:13:15 +0200 (CEST) Received: by h08.hostsharing.net (Postfix, from userid 100393) id E4AED16038D; Thu, 20 Aug 2020 10:13:14 +0200 (CEST) Date: Thu, 20 Aug 2020 10:13:14 +0200 From: Lukas Wunner To: Mika Westerberg Cc: Bjorn Helgaas , Kai-Heng Feng , Karol Herbst , Lyude Paul , Patrick Volkerding , Ben Skeggs , linux-pci@vger.kernel.org Subject: Re: [PATCH] PCI/PM: Assume ports without DLL Link Active train links in 100 ms Message-ID: <20200820081314.l25cjoehbnvbjbrk@wunner.de> References: <20200819130625.12778-1-mika.westerberg@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200819130625.12778-1-mika.westerberg@linux.intel.com> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Aug 19, 2020 at 04:06:25PM +0300, Mika Westerberg wrote: > Sec 7.5.3.6 requires such Ports to support DLL Link Active reporting, but > at least the Intel JHL6240 Thunderbolt 3 Bridge [8086:15c0] and the Intel > JHL7540 Thunderbolt 3 Bridge [8086:15ea] do not. [...] > + * Also do the same for devices that have power management disabled > + * by their driver and are completely power managed through the > + * root port power resource instead. This is a special case for > + * nouveau. > */ > - if (!pci_is_pcie(dev)) { > + if (!pci_is_pcie(dev) || !child->pm_cap) { It sounds like the above-mentioned Thunderbolt controllers are broken, not the Nvidia cards, so to me (as an outside observer) it would seem more logical that a quirk for the former is needed. The code comment suggests that nouveau somehow has a problem, but that doesn't seem to be the case (IIUC). Also, it's a little ugly to have references to specific drivers in PCI core code. Maybe this can be fixed with quirks for the Thunderbolt controllers which set a flag, and that flag causes the 1000 msec wait to be skipped? Thanks, Lukas