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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 9DDD3C433FE for ; Thu, 16 Sep 2021 16:39:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 86B3861BF6 for ; Thu, 16 Sep 2021 16:39:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244610AbhIPQjV (ORCPT ); Thu, 16 Sep 2021 12:39:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:44970 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242062AbhIPQbq (ORCPT ); Thu, 16 Sep 2021 12:31:46 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 344AC6187A; Thu, 16 Sep 2021 16:19:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1631809181; bh=tecI0xFXGZah/qzfpOPocp2W8hgrOZ2sSXszrl8VFlU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=b4Lp7etH5pNwfhyeP8GM9aUqC8se3MUUHpr9BxxYtEFEru/IuRvQDbc8d8tTOWAXp Jvu7oF+NssJQCB+6VDTJA9u6iyGrP7FpgfBg83GBGtpsiYS2EmIZnyEN1SuR7PCJ3p EblvoB4EdnO0x950YbB9tdz1tssSTFlrFKg9KUnk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stuart Hayes , Bjorn Helgaas , Lukas Wunner Subject: [PATCH 5.13 060/380] PCI/portdrv: Enable Bandwidth Notification only if port supports it Date: Thu, 16 Sep 2021 17:56:57 +0200 Message-Id: <20210916155806.034630655@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210916155803.966362085@linuxfoundation.org> References: <20210916155803.966362085@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Stuart Hayes commit 00823dcbdd415c868390feaca16f0265101efab4 upstream. Previously we assumed that all Root Ports and Switch Downstream Ports supported Link Bandwidth Notification. Per spec, this is only required for Ports supporting Links wider than x1 and/or multiple Link speeds (PCIe r5.0, sec 7.5.3.6). Because we assumed all Ports supported it, we tried to set up a Bandwidth Notification IRQ, which failed for devices that don't support IRQs at all, which meant pcieport didn't attach to the Port at all. Check the Link Bandwidth Notification Capability bit and enable the service only when the Port supports it. [bhelgaas: commit log] Fixes: e8303bb7a75c ("PCI/LINK: Report degraded links via link bandwidth notification") Link: https://lore.kernel.org/r/20210512213314.7778-1-stuart.w.hayes@gmail.com Signed-off-by: Stuart Hayes Signed-off-by: Bjorn Helgaas Reviewed-by: Lukas Wunner Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/pci/pcie/portdrv_core.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) --- a/drivers/pci/pcie/portdrv_core.c +++ b/drivers/pci/pcie/portdrv_core.c @@ -257,8 +257,13 @@ static int get_port_device_capability(st services |= PCIE_PORT_SERVICE_DPC; if (pci_pcie_type(dev) == PCI_EXP_TYPE_DOWNSTREAM || - pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) - services |= PCIE_PORT_SERVICE_BWNOTIF; + pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) { + u32 linkcap; + + pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &linkcap); + if (linkcap & PCI_EXP_LNKCAP_LBNC) + services |= PCIE_PORT_SERVICE_BWNOTIF; + } return services; }