From patchwork Mon Nov 12 16:06:25 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mika Westerberg X-Patchwork-Id: 10678941 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 6BBB513BF for ; Mon, 12 Nov 2018 16:06:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5B3912909F for ; Mon, 12 Nov 2018 16:06:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4E9B929237; Mon, 12 Nov 2018 16:06:56 +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=unavailable 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 DE9052909F for ; Mon, 12 Nov 2018 16:06:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729995AbeKMCAl (ORCPT ); Mon, 12 Nov 2018 21:00:41 -0500 Received: from mga18.intel.com ([134.134.136.126]:39016 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729891AbeKMCA1 (ORCPT ); Mon, 12 Nov 2018 21:00:27 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 12 Nov 2018 08:06:34 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,495,1534834800"; d="scan'208";a="273385346" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga005.jf.intel.com with ESMTP; 12 Nov 2018 08:06:29 -0800 Received: by black.fi.intel.com (Postfix, from userid 1001) id 6B05B17F; Mon, 12 Nov 2018 18:06:28 +0200 (EET) From: Mika Westerberg To: iommu@lists.linux-foundation.org Cc: Joerg Roedel , David Woodhouse , Lu Baolu , Ashok Raj , Bjorn Helgaas , "Rafael J. Wysocki" , Jacob jun Pan , Andreas Noever , Michael Jamet , Yehezkel Bernat , Lukas Wunner , Christian Kellner , Mario.Limonciello@dell.com, Anthony Wong , Mika Westerberg , linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/4] PCI / ACPI: Identify external PCI devices Date: Mon, 12 Nov 2018 19:06:25 +0300 Message-Id: <20181112160628.86620-2-mika.westerberg@linux.intel.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181112160628.86620-1-mika.westerberg@linux.intel.com> References: <20181112160628.86620-1-mika.westerberg@linux.intel.com> 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 Recent systems shipping Windows 10 version 1803 or later may support IOMMU based DMA protection. This means that the platform utilizes IOMMU to prevent DMA attacks over externally exposed PCIe root ports (typically Thunderbolt ports) The system BIOS marks these PCIe root ports as being externally facing ports by implementing following ACPI _DSD under the root port in question: Name (_DSD, Package () { ToUUID ("efcc06cc-73ac-4bc3-bff0-76143807c389"), Package () { Package () {"ExternalFacingPort", 1}, Package () {"UID", 0 } } }) This is documented [1]. To make it possible for IOMMU code to identify these external devices, we look up for this property and mark all children devices (including the root port itself) with a new flag (->is_external). [1] https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#identifying-externally-exposed-pcie-root-ports Signed-off-by: Mika Westerberg --- drivers/acpi/property.c | 3 +++ drivers/pci/pci-acpi.c | 13 +++++++++++++ drivers/pci/probe.c | 23 +++++++++++++++++++++++ include/linux/pci.h | 1 + 4 files changed, 40 insertions(+) diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c index 8c7c4583b52d..4bdad32f62c8 100644 --- a/drivers/acpi/property.c +++ b/drivers/acpi/property.c @@ -31,6 +31,9 @@ static const guid_t prp_guids[] = { /* Hotplug in D3 GUID: 6211e2c0-58a3-4af3-90e1-927a4e0c55a4 */ GUID_INIT(0x6211e2c0, 0x58a3, 0x4af3, 0x90, 0xe1, 0x92, 0x7a, 0x4e, 0x0c, 0x55, 0xa4), + /* External facing port GUID: efcc06cc-73ac-4bc3-bff0-76143807c389 */ + GUID_INIT(0xefcc06cc, 0x73ac, 0x4bc3, + 0xbf, 0xf0, 0x76, 0x14, 0x38, 0x07, 0xc3, 0x89), }; static const guid_t ads_guid = diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c index 2a4aa6468579..fc193279d24d 100644 --- a/drivers/pci/pci-acpi.c +++ b/drivers/pci/pci-acpi.c @@ -789,6 +789,18 @@ static void pci_acpi_optimize_delay(struct pci_dev *pdev, ACPI_FREE(obj); } +static void pci_acpi_set_external(struct pci_dev *dev) +{ + u8 val; + + if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT) + return; + if (device_property_read_u8(&dev->dev, "ExternalFacingPort", &val)) + return; + + dev->is_external = val == 1; +} + static void pci_acpi_setup(struct device *dev) { struct pci_dev *pci_dev = to_pci_dev(dev); @@ -803,6 +815,7 @@ static void pci_acpi_setup(struct device *dev) set_dev_node(dev, node); pci_acpi_optimize_delay(pci_dev, adev->handle); + pci_acpi_set_external(pci_dev); pci_acpi_add_pm_notifier(adev, pci_dev); if (!adev->wakeup.flags.valid) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index b1c05b5054a0..f1db195a4a90 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1378,6 +1378,27 @@ static void set_pcie_thunderbolt(struct pci_dev *dev) } } +static void set_pcie_external(struct pci_dev *dev) +{ + struct pci_dev *parent; + + /* + * Walk up the device hierarchy and check for any upstream + * bridge that has is_external_facing set to true. This means + * the hierarchy is below PCIe port that is exposed externally + * (such as Thunderbolt). + */ + parent = pci_upstream_bridge(dev); + while (parent) { + if (parent->is_external) { + dev->is_external = true; + break; + } + + parent = pci_upstream_bridge(parent); + } +} + /** * pci_ext_cfg_is_aliased - Is ext config space just an alias of std config? * @dev: PCI device @@ -1638,6 +1659,8 @@ int pci_setup_device(struct pci_dev *dev) /* Need to have dev->cfg_size ready */ set_pcie_thunderbolt(dev); + set_pcie_external(dev); + /* "Unknown power state" */ dev->current_state = PCI_UNKNOWN; diff --git a/include/linux/pci.h b/include/linux/pci.h index 11c71c4ecf75..e1c0e032da55 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -396,6 +396,7 @@ struct pci_dev { unsigned int is_hotplug_bridge:1; unsigned int shpc_managed:1; /* SHPC owned by shpchp */ unsigned int is_thunderbolt:1; /* Thunderbolt controller */ + unsigned int is_external:1; /* External PCIe device */ unsigned int __aer_firmware_first_valid:1; unsigned int __aer_firmware_first:1; unsigned int broken_intx_masking:1; /* INTx masking can't be used */