From patchwork Sun Jan 8 08:41:45 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 9503347 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 8859F60710 for ; Sun, 8 Jan 2017 08:43:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8046827BE5 for ; Sun, 8 Jan 2017 08:43:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7496C2832B; Sun, 8 Jan 2017 08:43:15 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 12B3B27BE5 for ; Sun, 8 Jan 2017 08:43:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031690AbdAHInH (ORCPT ); Sun, 8 Jan 2017 03:43:07 -0500 Received: from mailout2.hostsharing.net ([83.223.90.233]:38949 "EHLO mailout2.hostsharing.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031673AbdAHInA (ORCPT ); Sun, 8 Jan 2017 03:43:00 -0500 Received: from h08.hostsharing.net (h08.hostsharing.net [83.223.95.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mailout2.hostsharing.net (Postfix) with ESMTPS id BCBB310189B52; Sun, 8 Jan 2017 09:42:55 +0100 (CET) Received: from localhost (3-38-90-81.adsl.cmo.de [81.90.38.3]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id 3B17B6042B98; Sun, 8 Jan 2017 09:42:54 +0100 (CET) X-Mailbox-Line: From 89e0512762e0062ad1f1884ebfaaf71e3b731237 Mon Sep 17 00:00:00 2001 Message-Id: <89e0512762e0062ad1f1884ebfaaf71e3b731237.1483806825.git.lukas@wunner.de> In-Reply-To: References: From: Lukas Wunner Date: Sun, 8 Jan 2017 09:41:45 +0100 Subject: [PATCH v4 3/8] PCI: Don't block runtime PM for Thunderbolt host hotplug ports To: Greg Kroah-Hartman , linux-kernel@vger.kernel.org Cc: Andreas Noever , linux-pci@vger.kernel.org, linux-pm@vger.kernel.org, Chen Yu , Tomas Winkler , Amir Levy , Bjorn Helgaas , Mika Westerberg , "Rafael J. Wysocki" Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Hotplug ports generally block their parents from suspending to D3hot as otherwise their interrupts couldn't be delivered. An exception are Thunderbolt host controllers: They have a separate GPIO pin to side-band signal plug events even if the controller is powered down or its parent ports are suspended to D3. They can be told apart from Thunderbolt controllers in attached devices by checking if they're situated below a non-Thunderbolt device (typically a root port, or the downstream port of a PCIe switch in the case of the MacPro6,1). To enable runtime PM for Thunderbolt on the Mac, the downstream bridges of a host controller must not block runtime PM on the upstream bridge as power to the chip is only cut once the upstream bridge has suspended. Amend the condition in pci_dev_check_d3cold() accordingly. Cc: Mika Westerberg Cc: Rafael J. Wysocki Cc: Andreas Noever Cc: Tomas Winkler Cc: Amir Levy Signed-off-by: Lukas Wunner --- drivers/pci/pci.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 8ed098d..0b03fe7 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -2271,6 +2271,7 @@ bool pci_bridge_d3_possible(struct pci_dev *bridge) static int pci_dev_check_d3cold(struct pci_dev *dev, void *data) { + struct pci_dev *parent, *grandparent; bool *d3cold_ok = data; if (/* The device needs to be allowed to go D3cold ... */ @@ -2284,7 +2285,17 @@ static int pci_dev_check_d3cold(struct pci_dev *dev, void *data) !pci_power_manageable(dev) || /* Hotplug interrupts cannot be delivered if the link is down. */ - dev->is_hotplug_bridge) + (dev->is_hotplug_bridge && + + /* + * Exception: Thunderbolt host controllers have a pin to + * side-band signal plug events. Their hotplug ports are + * recognizable by having a non-Thunderbolt device as + * grandparent. + */ + !(dev->is_thunderbolt && (parent = pci_upstream_bridge(dev)) && + (grandparent = pci_upstream_bridge(parent)) && + !grandparent->is_thunderbolt))) *d3cold_ok = false;