From patchwork Fri Jun 24 04:19:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 12893673 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 96244CCA486 for ; Fri, 24 Jun 2022 04:20:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229879AbiFXEUN (ORCPT ); Fri, 24 Jun 2022 00:20:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57518 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229584AbiFXEUL (ORCPT ); Fri, 24 Jun 2022 00:20:11 -0400 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 292A44FC6A; Thu, 23 Jun 2022 21:20:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1656044411; x=1687580411; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=HUsFMVeTjVGLdCwrcUoS1fkV2YbMF30CWyhsa214UuI=; b=HK1nvKK5EMTeGzdb72I6kVcmrTaQJu1M+XKeU+VVAehqrW+u8MxDbmo5 ytn2Y32wkgrSHww9tAV+G8xAHUf6oBzF2R3wURJvP/3N1Fo3vX+eUTglJ 9gsYkTkdjSTMV38c4z8AP6m0CDvPWt27JAarHUMqQHA8h7bVqgK5fBaK4 ObgQ77vDA6GvvM7QJBTUbDORLDeORWTreSh2vkjgctW/RXhpXWS8gwizv 4c53uqY/+24olRoW2vzfE7PmP35q3yQpUfrlbAT6zH0zNYVsru360Hr+b BPZ9wPgyib5HcWDU29Sp6Z2KTme3moTUQzyVTaNhZDamaXcEPHc0xtML/ g==; X-IronPort-AV: E=McAfee;i="6400,9594,10387"; a="367237998" X-IronPort-AV: E=Sophos;i="5.92,218,1650956400"; d="scan'208";a="367237998" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Jun 2022 21:20:10 -0700 X-IronPort-AV: E=Sophos;i="5.92,218,1650956400"; d="scan'208";a="645092906" Received: from daharell-mobl2.amr.corp.intel.com (HELO dwillia2-xfh.intel.com) ([10.209.66.176]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Jun 2022 21:20:10 -0700 From: Dan Williams To: linux-cxl@vger.kernel.org Cc: nvdimm@lists.linux.dev, linux-pci@vger.kernel.org, patches@lists.linux.dev, hch@lst.de, Dan Williams Subject: [PATCH 29/46] cxl/port: Cache CXL host bridge data Date: Thu, 23 Jun 2022 21:19:33 -0700 Message-Id: <20220624041950.559155-4-dan.j.williams@intel.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <165603869943.551046.3498980330327696732.stgit@dwillia2-xfh> References: <165603869943.551046.3498980330327696732.stgit@dwillia2-xfh> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org Region creation has need for checking host-bridge connectivity when adding endpoints to regions. Record, at port creation time, the host-bridge to provide a useful shortcut from any location in the topology to the most-significant ancestor. Signed-off-by: Dan Williams Reviewed-by: Jonathan Cameron --- drivers/cxl/core/port.c | 16 +++++++++++++++- drivers/cxl/cxl.h | 2 ++ 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index d2f6898940fa..c48f217e689a 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -546,6 +546,7 @@ static struct cxl_port *cxl_port_alloc(struct device *uport, if (rc < 0) goto err; port->id = rc; + port->uport = uport; /* * The top-level cxl_port "cxl_root" does not have a cxl_port as @@ -556,14 +557,27 @@ static struct cxl_port *cxl_port_alloc(struct device *uport, dev = &port->dev; if (parent_dport) { struct cxl_port *parent_port = parent_dport->port; + struct cxl_port *iter; port->depth = parent_port->depth + 1; port->parent_dport = parent_dport; dev->parent = &parent_port->dev; + /* + * walk to the host bridge, or the first ancestor that knows + * the host bridge + */ + iter = port; + while (!iter->host_bridge && + !is_cxl_root(to_cxl_port(iter->dev.parent))) + iter = to_cxl_port(iter->dev.parent); + if (iter->host_bridge) + port->host_bridge = iter->host_bridge; + else + port->host_bridge = iter->uport; + dev_dbg(uport, "host-bridge: %s\n", dev_name(port->host_bridge)); } else dev->parent = uport; - port->uport = uport; port->component_reg_phys = component_reg_phys; ida_init(&port->decoder_ida); port->dpa_end = -1; diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 8e2c1b393552..0211cf0d3574 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -331,6 +331,7 @@ struct cxl_nvdimm { * @component_reg_phys: component register capability base address (optional) * @dead: last ep has been removed, force port re-creation * @depth: How deep this port is relative to the root. depth 0 is the root. + * @host_bridge: Shortcut to the platform attach point for this port */ struct cxl_port { struct device dev; @@ -344,6 +345,7 @@ struct cxl_port { resource_size_t component_reg_phys; bool dead; unsigned int depth; + struct device *host_bridge; }; static inline struct cxl_dport *cxl_dport_load(struct cxl_port *port,