From patchwork Wed May 12 14:37:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dongdong Liu X-Patchwork-Id: 1477652 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4FgHTG0BS8z9sWQ for ; Thu, 13 May 2021 00:38:10 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231192AbhELOjP (ORCPT ); Wed, 12 May 2021 10:39:15 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:2645 "EHLO szxga05-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231310AbhELOjL (ORCPT ); Wed, 12 May 2021 10:39:11 -0400 Received: from DGGEMS406-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4FgHP81lGFzQmVD; Wed, 12 May 2021 22:34:36 +0800 (CST) Received: from SZX1000464847.huawei.com (10.21.59.169) by DGGEMS406-HUB.china.huawei.com (10.3.19.206) with Microsoft SMTP Server id 14.3.498.0; Wed, 12 May 2021 22:37:56 +0800 From: Dongdong Liu To: , , , , CC: , Subject: [PATCH V3 4/6] PCI: Enable 10-Bit tag support for PCIe Endpoint devices Date: Wed, 12 May 2021 22:37:35 +0800 Message-ID: <20210512143737.42352-5-liudongdong3@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210512143737.42352-1-liudongdong3@huawei.com> References: <20210512143737.42352-1-liudongdong3@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.21.59.169] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org 10-Bit Tag capability, introduced in PCIe-4.0 increases the total Tag field size from 8 bits to 10 bits. For platforms where the RC supports 10-Bit Tag Completer capability, it is highly recommended for platform firmware or operating software that configures PCIe hierarchies to Set the 10-Bit Tag Requester Enable bit automatically in Endpoints with 10-Bit Tag Requester capability. This enables the important class of 10-Bit Tag capable adapters that send Memory Read Requests only to host memory. Signed-off-by: Dongdong Liu --- drivers/pci/probe.c | 36 ++++++++++++++++++++++++++++++++++++ include/linux/pci.h | 2 ++ 2 files changed, 38 insertions(+) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index b9942cc..dfcd3d2 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2046,6 +2046,41 @@ int pci_configure_extended_tags(struct pci_dev *dev, void *ign) return 0; } +static void pci_configure_10bit_tags(struct pci_dev *dev) +{ + struct pci_dev *bridge; + + if (!pci_is_pcie(dev)) + return; + + if (!(dev->pcie_devcap2 & PCI_EXP_DEVCAP2_10BIT_TAG_COMP)) + return; + + if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) { + dev->ext_10bit_tag = 1; + return; + } + + bridge = pci_upstream_bridge(dev); + if (bridge && bridge->ext_10bit_tag) + dev->ext_10bit_tag = 1; + + /* + * 10-Bit Tag Requester Enable in Device Control 2 Register is RsvdP + * for VF. + */ + if (dev->is_virtfn) + return; + + if (pci_pcie_type(dev) == PCI_EXP_TYPE_ENDPOINT && + dev->ext_10bit_tag == 1 && + (dev->pcie_devcap2 & PCI_EXP_DEVCAP2_10BIT_TAG_REQ)) { + pci_dbg(dev, "enabling 10-Bit Tag Requester\n"); + pcie_capability_set_word(dev, PCI_EXP_DEVCTL2, + PCI_EXP_DEVCTL2_10BIT_TAG_REQ_EN); + } +} + /** * pcie_relaxed_ordering_enabled - Probe for PCIe relaxed ordering enable * @dev: PCI device to query @@ -2182,6 +2217,7 @@ static void pci_configure_device(struct pci_dev *dev) { pci_configure_mps(dev); pci_configure_extended_tags(dev, NULL); + pci_configure_10bit_tags(dev); pci_configure_relaxed_ordering(dev); pci_configure_ltr(dev); pci_configure_eetlp_prefix(dev); diff --git a/include/linux/pci.h b/include/linux/pci.h index 2965620..f2b2b5b 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -393,6 +393,8 @@ struct pci_dev { #endif unsigned int eetlp_prefix_path:1; /* End-to-End TLP Prefix */ + unsigned int ext_10bit_tag:1; /* 10-Bit Tag Completer Supported + from root to here */ pci_channel_state_t error_state; /* Current connectivity state */ struct device dev; /* Generic device interface */