From patchwork Mon Oct 1 12:49:34 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Petazzoni X-Patchwork-Id: 10622093 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E5A8D1515 for ; Mon, 1 Oct 2018 12:50:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D831329570 for ; Mon, 1 Oct 2018 12:50:02 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CA04429580; Mon, 1 Oct 2018 12:50:02 +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=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, 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 0530129570 for ; Mon, 1 Oct 2018 12:50:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729169AbeJAT1l (ORCPT ); Mon, 1 Oct 2018 15:27:41 -0400 Received: from mail.bootlin.com ([62.4.15.54]:56573 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729149AbeJAT1l (ORCPT ); Mon, 1 Oct 2018 15:27:41 -0400 Received: by mail.bootlin.com (Postfix, from userid 110) id A5AFB20725; Mon, 1 Oct 2018 14:49:57 +0200 (CEST) Received: from localhost (AAubervilliers-681-1-24-95.w90-88.abo.wanadoo.fr [90.88.144.95]) by mail.bootlin.com (Postfix) with ESMTPSA id 6EA68206FF; Mon, 1 Oct 2018 14:49:57 +0200 (CEST) From: Thomas Petazzoni To: Bjorn Helgaas , Lorenzo Pieralisi , linux-pci@vger.kernel.org, =?utf-8?q?Jan_Kundr=C3=A1t?= Cc: Jason Cooper , Andrew Lunn , Sebastian Hesselbarth , Gregory Clement , linux-arm-kernel@lists.infradead.org, Russell King , Thomas Petazzoni Subject: [PATCH] PCI: mvebu: Fix PCI I/O mapping creation sequence Date: Mon, 1 Oct 2018 14:49:34 +0200 Message-Id: <20181001124934.7222-1-thomas.petazzoni@bootlin.com> X-Mailer: git-send-email 2.14.4 MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Commit ee1604381a371 ("PCI: mvebu: Only remap I/O space if configured") had the side effect that the PCI I/O mapping was created much earlier than before, at a point where the probe() of the driver could still fail. This is for example a problem if one gets an -EPROBE_DEFER at some point during probe(), after pci_ioremap_io() has been called. Indeed, there is currently no function to undo what pci_ioremap_io() did, and switching to pci_remap_iospace() is not an option in pci-mvebu due to the need for special memory attributes on Armada 38x. Reverting ee1604381a371 ("PCI: mvebu: Only remap I/O space if configured") would be a possibility, but it would require also reverting 42342073e38b5 ("PCI: mvebu: Convert to use pci_host_bridge directly"). So instead, we use an open-coded version of pci_host_probe() that creates the PCI I/O mapping at a point where we are guaranteed not to fail anymore. Reported-by: Jan Kundrát Fixes: ee1604381a371 ("PCI: mvebu: Only remap I/O space if configured") Signed-off-by: Thomas Petazzoni Acked-by: Lorenzo Pieralisi Tested-by: Jan Kundrát --- drivers/pci/controller/pci-mvebu.c | 52 +++++++++++++++++++++++++++++++++++--- 1 file changed, 48 insertions(+), 4 deletions(-) diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c index 50eb0729385b..a41d79b8d46a 100644 --- a/drivers/pci/controller/pci-mvebu.c +++ b/drivers/pci/controller/pci-mvebu.c @@ -1145,7 +1145,6 @@ static int mvebu_pcie_parse_request_resources(struct mvebu_pcie *pcie) { struct device *dev = &pcie->pdev->dev; struct device_node *np = dev->of_node; - unsigned int i; int ret; INIT_LIST_HEAD(&pcie->resources); @@ -1179,13 +1178,58 @@ static int mvebu_pcie_parse_request_resources(struct mvebu_pcie *pcie) resource_size(&pcie->io) - 1); pcie->realio.name = "PCI I/O"; + pci_add_resource(&pcie->resources, &pcie->realio); + } + + return devm_request_pci_bus_resources(dev, &pcie->resources); +} + +/* + * This is a copy of pci_host_probe(), except that it does the I/O + * remap as the last step, once we are sure we won't fail. + * + * It should be removed once the I/O remap error handling issue has + * been sorted out. + */ +static int mvebu_pci_host_probe(struct pci_host_bridge *bridge) +{ + struct mvebu_pcie *pcie; + struct pci_bus *bus, *child; + int ret; + + ret = pci_scan_root_bus_bridge(bridge); + if (ret < 0) { + dev_err(bridge->dev.parent, "Scanning root bridge failed"); + return ret; + } + + pcie = pci_host_bridge_priv(bridge); + if (resource_size(&pcie->io) != 0) { + unsigned int i; + for (i = 0; i < resource_size(&pcie->realio); i += SZ_64K) pci_ioremap_io(i, pcie->io.start + i); + } - pci_add_resource(&pcie->resources, &pcie->realio); + bus = bridge->bus; + + /* + * We insert PCI resources into the iomem_resource and + * ioport_resource trees in either pci_bus_claim_resources() + * or pci_bus_assign_resources(). + */ + if (pci_has_flag(PCI_PROBE_ONLY)) { + pci_bus_claim_resources(bus); + } else { + pci_bus_size_bridges(bus); + pci_bus_assign_resources(bus); + + list_for_each_entry(child, &bus->children, node) + pcie_bus_configure_settings(child); } - return devm_request_pci_bus_resources(dev, &pcie->resources); + pci_bus_add_devices(bus); + return 0; } static int mvebu_pcie_probe(struct platform_device *pdev) @@ -1268,7 +1312,7 @@ static int mvebu_pcie_probe(struct platform_device *pdev) bridge->align_resource = mvebu_pcie_align_resource; bridge->msi = pcie->msi; - return pci_host_probe(bridge); + return mvebu_pci_host_probe(bridge); } static const struct of_device_id mvebu_pcie_of_match_table[] = {