From patchwork Tue Feb 1 00:34:40 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 12731322 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D5C9CC433EF for ; Tue, 1 Feb 2022 00:34:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229598AbiBAAel (ORCPT ); Mon, 31 Jan 2022 19:34:41 -0500 Received: from mga02.intel.com ([134.134.136.20]:10714 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230433AbiBAAek (ORCPT ); Mon, 31 Jan 2022 19:34:40 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1643675681; x=1675211681; h=subject:from:to:cc:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=fjf5FB26voT1T0ARPJIzRUTIpVRARtKXAGh8m512xik=; b=EvmhFnAmbKLMBckZ5N11xjTSKb4qcjcxber0idTqilier37o8THcHPc7 udF0gUR+7rMqMA3Gzy2XIe5t3MuvEx6iaOBjDKKYKk9sxpGjge3Eo6cZA 4xuBMQX/yRy2soiVMpYQg6m0/n5lLG6c86O7uCnIbKT2Aral/YINUASCp ALovAzKGSosYYP+G7ADvn7gde3UhkOX/UhSWjkajX+TDFHnPLmO1EBYGH fQIY/bw5sdbrmUIJz0QrlSx9LmIalhiNGay9oPzzyOTUBC3cbKTi+ZD3S V5fw046kaKU//WO+n8THaWoKuZj+yqOJ0JJXM5S7ycQFm+t6crOkKqzs7 w==; X-IronPort-AV: E=McAfee;i="6200,9189,10244"; a="234983264" X-IronPort-AV: E=Sophos;i="5.88,332,1635231600"; d="scan'208";a="234983264" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Jan 2022 16:34:40 -0800 X-IronPort-AV: E=Sophos;i="5.88,332,1635231600"; d="scan'208";a="522864865" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.25]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Jan 2022 16:34:40 -0800 Subject: [PATCH v6 18/40] cxl/pmem: Introduce a find_cxl_root() helper From: Dan Williams To: linux-cxl@vger.kernel.org Cc: Ben Widawsky , linux-pci@vger.kernel.org, nvdimm@lists.linux.dev Date: Mon, 31 Jan 2022 16:34:40 -0800 Message-ID: <164367562182.225521.9488555616768096049.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <164324151672.3935633.11277011056733051668.stgit@dwillia2-desk3.amr.corp.intel.com> References: <164324151672.3935633.11277011056733051668.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-3-g996c MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org In preparation for switch port enumeration while also preserving the potential for multi-domain / multi-root CXL topologies. Introduce a 'struct device' generic mechanism for retrieving a root CXL port, if one is registered. Note that the only known multi-domain CXL configurations are running the cxl_test unit test on a system that also publishes an ACPI0017 device. With this in hand the nvdimm-bridge lookup can be with device_find_child() instead of bus_find_device() + custom mocked lookup infrastructure in cxl_test. The mechanism looks for a 2nd level port since the root level topology is platform-firmware specific and the 2nd level down follows standard PCIe topology expectations. The cxl_acpi 2nd level is associated with a PCIe Root Port. Reported-by: Ben Widawsky Signed-off-by: Dan Williams Reviewed-by: Jonathan Cameron --- Changes since v5: - Shorten 'match_cxl_root_child' name to improve line wrapping (Jonathan) drivers/cxl/core/pmem.c | 14 ++++++++---- drivers/cxl/core/port.c | 49 +++++++++++++++++++++++++++++++++++++++++ drivers/cxl/cxl.h | 1 + tools/testing/cxl/Kbuild | 2 -- tools/testing/cxl/mock_pmem.c | 24 -------------------- 5 files changed, 60 insertions(+), 30 deletions(-) delete mode 100644 tools/testing/cxl/mock_pmem.c diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c index 40b3f5030496..8de240c4d96b 100644 --- a/drivers/cxl/core/pmem.c +++ b/drivers/cxl/core/pmem.c @@ -57,24 +57,30 @@ bool is_cxl_nvdimm_bridge(struct device *dev) } EXPORT_SYMBOL_NS_GPL(is_cxl_nvdimm_bridge, CXL); -__mock int match_nvdimm_bridge(struct device *dev, const void *data) +static int match_nvdimm_bridge(struct device *dev, void *data) { return is_cxl_nvdimm_bridge(dev); } struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_nvdimm *cxl_nvd) { + struct cxl_port *port = find_cxl_root(&cxl_nvd->dev); struct device *dev; - dev = bus_find_device(&cxl_bus_type, NULL, cxl_nvd, match_nvdimm_bridge); + if (!port) + return NULL; + + dev = device_find_child(&port->dev, NULL, match_nvdimm_bridge); + put_device(&port->dev); + if (!dev) return NULL; + return to_cxl_nvdimm_bridge(dev); } EXPORT_SYMBOL_NS_GPL(cxl_find_nvdimm_bridge, CXL); -static struct cxl_nvdimm_bridge * -cxl_nvdimm_bridge_alloc(struct cxl_port *port) +static struct cxl_nvdimm_bridge *cxl_nvdimm_bridge_alloc(struct cxl_port *port) { struct cxl_nvdimm_bridge *cxl_nvb; struct device *dev; diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index 2a4230d685d5..af7a515e4572 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -455,6 +455,55 @@ int devm_cxl_register_pci_bus(struct device *host, struct device *uport, } EXPORT_SYMBOL_NS_GPL(devm_cxl_register_pci_bus, CXL); +/* Find a 2nd level CXL port that has a dport that is an ancestor of @match */ +static int match_root_child(struct device *dev, const void *match) +{ + const struct device *iter = NULL; + struct cxl_port *port, *parent; + struct cxl_dport *dport; + + if (!is_cxl_port(dev)) + return 0; + + port = to_cxl_port(dev); + if (is_cxl_root(port)) + return 0; + + parent = to_cxl_port(port->dev.parent); + if (!is_cxl_root(parent)) + return 0; + + cxl_device_lock(&port->dev); + list_for_each_entry(dport, &port->dports, list) { + iter = match; + while (iter) { + if (iter == dport->dport) + goto out; + iter = iter->parent; + } + } +out: + cxl_device_unlock(&port->dev); + + return !!iter; +} + +struct cxl_port *find_cxl_root(struct device *dev) +{ + struct device *port_dev; + struct cxl_port *root; + + port_dev = bus_find_device(&cxl_bus_type, NULL, dev, match_root_child); + if (!port_dev) + return NULL; + + root = to_cxl_port(port_dev->parent); + get_device(&root->dev); + put_device(port_dev); + return root; +} +EXPORT_SYMBOL_NS_GPL(find_cxl_root, CXL); + static struct cxl_dport *find_dport(struct cxl_port *port, int id) { struct cxl_dport *dport; diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 4d4cc8292137..61b0db526fa2 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -304,6 +304,7 @@ struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport, int cxl_add_dport(struct cxl_port *port, struct device *dport, int port_id, resource_size_t component_reg_phys); +struct cxl_port *find_cxl_root(struct device *dev); struct cxl_decoder *to_cxl_decoder(struct device *dev); bool is_root_decoder(struct device *dev); diff --git a/tools/testing/cxl/Kbuild b/tools/testing/cxl/Kbuild index 3299fb0977b2..ddaee8a2c418 100644 --- a/tools/testing/cxl/Kbuild +++ b/tools/testing/cxl/Kbuild @@ -32,6 +32,4 @@ cxl_core-y += $(CXL_CORE_SRC)/memdev.o cxl_core-y += $(CXL_CORE_SRC)/mbox.o cxl_core-y += config_check.o -cxl_core-y += mock_pmem.o - obj-m += test/ diff --git a/tools/testing/cxl/mock_pmem.c b/tools/testing/cxl/mock_pmem.c deleted file mode 100644 index f7315e6f52c0..000000000000 --- a/tools/testing/cxl/mock_pmem.c +++ /dev/null @@ -1,24 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* Copyright(c) 2021 Intel Corporation. All rights reserved. */ -#include -#include "test/mock.h" -#include - -int match_nvdimm_bridge(struct device *dev, const void *data) -{ - int index, rc = 0; - struct cxl_mock_ops *ops = get_cxl_mock_ops(&index); - const struct cxl_nvdimm *cxl_nvd = data; - - if (ops) { - if (dev->type == &cxl_nvdimm_bridge_type && - (ops->is_mock_dev(dev->parent->parent) == - ops->is_mock_dev(cxl_nvd->dev.parent->parent))) - rc = 1; - } else - rc = dev->type == &cxl_nvdimm_bridge_type; - - put_cxl_mock_ops(index); - - return rc; -}