From patchwork Wed Mar 24 12:19:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kishon Vijay Abraham I X-Patchwork-Id: 12160957 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=-17.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 72673C433E1 for ; Wed, 24 Mar 2021 12:22:22 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0073F61A06 for ; Wed, 24 Mar 2021 12:22:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0073F61A06 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=ti.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-ID:Date: Subject:CC:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=hXKvJY4iC+//VHNYx/Kqv5XoljzxHN4x35Bhj/96M3A=; b=O4ErKH25zQg3UOtOCt4BYYsxv lgWXS1sIKboxXpijbVZZoB0axyd1FzLU60HeNsBEbeCt9J5xw2aPIbF6ybCO06Vmyf/3aVpJhFYxp nWQRbTayqwUCTt/AN1zyELevKuUgvMSYEE8umUAyZ0hjgnMky4pzv3piZvgy2lo7WqFRWu0lKPnb1 xQcOgAEdkUNC090sgXomjXwLF3TIu+Rsz85R3wbPeTNw9EsoHPwQN69GmyOfdTKLisPivy8DljFxd inwAYk7eKU9A7UoMkX3CJ4X8zdU6PGCd0jvE9xyasWCiXH+MxuYbkIGZ9eKur6QquTguBuNGgJZ5w 5JL3J4U7Q==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lP2UE-00H2IS-7R; Wed, 24 Mar 2021 12:19:46 +0000 Received: from fllv0015.ext.ti.com ([198.47.19.141]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lP2Tn-00H2C0-4L for linux-arm-kernel@lists.infradead.org; Wed, 24 Mar 2021 12:19:22 +0000 Received: from lelv0266.itg.ti.com ([10.180.67.225]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 12OCJDSJ012494; Wed, 24 Mar 2021 07:19:13 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1616588353; bh=cowBO1dcfWlhVDX9uRu8VrJ6Mb2a92ZE4IRbCBJpBKo=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=sTbKL1tlWI5F8XPGpDfHYCsupd8u88PTi3MsGp7tw4V+6AXZr6KaLvLo2zBnpFJ+k X+N4uz9xmk7ncs4UCM8Bmwi8ze/945mX3mGzgvYmiz4GOGLBosucAjLr1PQcpFfd6M v7O/AjvFq0P8QAgv8QnLt56wu+UEGNEphMciw1W8= Received: from DFLE106.ent.ti.com (dfle106.ent.ti.com [10.64.6.27]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 12OCJD1V021542 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 24 Mar 2021 07:19:13 -0500 Received: from DFLE104.ent.ti.com (10.64.6.25) by DFLE106.ent.ti.com (10.64.6.27) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Wed, 24 Mar 2021 07:19:12 -0500 Received: from lelv0327.itg.ti.com (10.180.67.183) by DFLE104.ent.ti.com (10.64.6.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2 via Frontend Transport; Wed, 24 Mar 2021 07:19:13 -0500 Received: from a0393678-ssd.dhcp.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0327.itg.ti.com (8.15.2/8.15.2) with ESMTP id 12OCJ1Ci121061; Wed, 24 Mar 2021 07:19:09 -0500 From: Kishon Vijay Abraham I To: Kishon Vijay Abraham I , Lorenzo Pieralisi , Rob Herring , Bjorn Helgaas CC: , , , Lokesh Vutla Subject: [PATCH 2/2] PCI: keystone: Add link up check in ks_child_pcie_ops.map_bus() Date: Wed, 24 Mar 2021 17:49:01 +0530 Message-ID: <20210324121901.1856-3-kishon@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210324121901.1856-1-kishon@ti.com> References: <20210324121901.1856-1-kishon@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210324_121919_515420_FA33CF58 X-CRM114-Status: GOOD ( 14.79 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org K2G forwardS the error triggered by a link-down state (e.g., no connected endpoint device) on the system bus for PCI configuration transactions; these errors are reported as an SError at system level, which is fatal and hangs the system. So fix it similar to how it was done in designware core driver commit 15b23906347c ("PCI: dwc: Add link up check in dw_child_pcie_ops.map_bus()"). Fixes: 10a797c6e54a ("PCI: dwc: keystone: Use pci_ops for config space accessors") Signed-off-by: Kishon Vijay Abraham I Cc: # v5.10 --- drivers/pci/controller/dwc/pci-keystone.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c index 7171ea70da49..4de8c8e5e3f2 100644 --- a/drivers/pci/controller/dwc/pci-keystone.c +++ b/drivers/pci/controller/dwc/pci-keystone.c @@ -432,6 +432,17 @@ static void __iomem *ks_pcie_other_map_bus(struct pci_bus *bus, struct keystone_pcie *ks_pcie = to_keystone_pcie(pci); u32 reg; + /* + * Checking whether the link is up here is a last line of defense + * against platforms that forward errors on the system bus as + * SError upon PCI configuration transactions issued when the link + * is down. This check is racy by definition and does not stop + * the system from triggering an SError if the link goes down + * after this check is performed. + */ + if (!dw_pcie_link_up(pci)) + return NULL; + reg = CFG_BUS(bus->number) | CFG_DEVICE(PCI_SLOT(devfn)) | CFG_FUNC(PCI_FUNC(devfn)); if (!pci_is_root_bus(bus->parent))