From patchwork Thu Sep 23 17:26:44 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ben Widawsky X-Patchwork-Id: 1531871 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org (client-ip=2404:9400:2:0:216:3eff:fee1:b9f1; helo=lists.ozlabs.org; envelope-from=linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org; receiver=) Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2404:9400:2:0:216:3eff:fee1:b9f1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4HFj0w6Qnyz9sX3 for ; Fri, 24 Sep 2021 03:32:48 +1000 (AEST) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4HFj0w5bPtz3cC6 for ; Fri, 24 Sep 2021 03:32:48 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=intel.com (client-ip=192.55.52.120; helo=mga04.intel.com; envelope-from=ben.widawsky@intel.com; receiver=) Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4HFhxr6f9Rz2yPM for ; Fri, 24 Sep 2021 03:30:08 +1000 (AEST) X-IronPort-AV: E=McAfee;i="6200,9189,10116"; a="222014574" X-IronPort-AV: E=Sophos;i="5.85,316,1624345200"; d="scan'208";a="222014574" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Sep 2021 10:26:56 -0700 X-IronPort-AV: E=Sophos;i="5.85,316,1624345200"; d="scan'208";a="704832559" Received: from unknown (HELO bad-guy.kumite) ([10.252.132.140]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Sep 2021 10:26:55 -0700 From: Ben Widawsky To: linux-cxl@vger.kernel.org Subject: [PATCH v2 6/9] PCI: Add pci_find_dvsec_capability to find designated VSEC Date: Thu, 23 Sep 2021 10:26:44 -0700 Message-Id: <20210923172647.72738-7-ben.widawsky@intel.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210923172647.72738-1-ben.widawsky@intel.com> References: <20210923172647.72738-1-ben.widawsky@intel.com> MIME-Version: 1.0 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Ben Widawsky , Andrew Donnellan , linux-pci@vger.kernel.org, Frederic Barrat , iommu@lists.linux-foundation.org, Bjorn Helgaas , "David E . Box" , Jonathan Cameron , Bjorn Helgaas , Dan Williams , Kan Liang , linuxppc-dev@lists.ozlabs.org, David Woodhouse , Lu Baolu Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Add pci_find_dvsec_capability to locate a Designated Vendor-Specific Extended Capability with the specified DVSEC ID. The Designated Vendor-Specific Extended Capability (DVSEC) allows one or more vendor specific capabilities that aren't tied to the vendor ID of the PCI component. DVSEC is critical for both the Compute Express Link (CXL) driver as well as the driver for OpenCAPI coherent accelerator (OCXL). Cc: David E. Box Cc: Jonathan Cameron Cc: Bjorn Helgaas Cc: Dan Williams Cc: linux-pci@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: Andrew Donnellan Cc: Lu Baolu Reviewed-by: Frederic Barrat Signed-off-by: Ben Widawsky Tested-by: Kan Liang Signed-off-by: Kan Liang Acked-by: Bjorn Helgaas Reviewed-by: Andrew Donnellan Reviewed-by: Jonathan Cameron --- drivers/pci/pci.c | 32 ++++++++++++++++++++++++++++++++ include/linux/pci.h | 1 + 2 files changed, 33 insertions(+) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index ce2ab62b64cf..94ac86ff28b0 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -732,6 +732,38 @@ u16 pci_find_vsec_capability(struct pci_dev *dev, u16 vendor, int cap) } EXPORT_SYMBOL_GPL(pci_find_vsec_capability); +/** + * pci_find_dvsec_capability - Find DVSEC for vendor + * @dev: PCI device to query + * @vendor: Vendor ID to match for the DVSEC + * @dvsec: Designated Vendor-specific capability ID + * + * If DVSEC has Vendor ID @vendor and DVSEC ID @dvsec return the capability + * offset in config space; otherwise return 0. + */ +u16 pci_find_dvsec_capability(struct pci_dev *dev, u16 vendor, u16 dvsec) +{ + int pos; + + pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_DVSEC); + if (!pos) + return 0; + + while (pos) { + u16 v, id; + + pci_read_config_word(dev, pos + PCI_DVSEC_HEADER1, &v); + pci_read_config_word(dev, pos + PCI_DVSEC_HEADER2, &id); + if (vendor == v && dvsec == id) + return pos; + + pos = pci_find_next_ext_capability(dev, pos, PCI_EXT_CAP_ID_DVSEC); + } + + return 0; +} +EXPORT_SYMBOL_GPL(pci_find_dvsec_capability); + /** * pci_find_parent_resource - return resource region of parent bus of given * region diff --git a/include/linux/pci.h b/include/linux/pci.h index cd8aa6fce204..c93ccfa4571b 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1130,6 +1130,7 @@ u16 pci_find_ext_capability(struct pci_dev *dev, int cap); u16 pci_find_next_ext_capability(struct pci_dev *dev, u16 pos, int cap); struct pci_bus *pci_find_next_bus(const struct pci_bus *from); u16 pci_find_vsec_capability(struct pci_dev *dev, u16 vendor, int cap); +u16 pci_find_dvsec_capability(struct pci_dev *dev, u16 vendor, u16 dvsec); u64 pci_get_dsn(struct pci_dev *dev);