From mboxrd@z Thu Jan 1 00:00:00 1970 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 C85C6CCA485 for ; Wed, 8 Jun 2022 00:38:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1388815AbiFHAc4 (ORCPT ); Tue, 7 Jun 2022 20:32:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44780 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1384053AbiFGVyE (ORCPT ); Tue, 7 Jun 2022 17:54:04 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BF7AC24851F; Tue, 7 Jun 2022 12:12:51 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 3A131B82375; Tue, 7 Jun 2022 19:12:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9D7D2C3411C; Tue, 7 Jun 2022 19:12:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654629161; bh=idSTYfKqID3ycqU0J+RD3lPvbre/1DQacziwM3YLQwg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Eq9lXSCAsc8ZK1UDNFf9xI/MR8VlhGvdDsCh1lGHHkaDbvURjpb/kgxmgsZqY08VJ wfs2dnIOeWvk8LtyFfEmU59FR9yvY7/kHuK62rCPtGjhKv/DblmSD5goMXoUodXWMw f4UWindDtRxeAxq1zNcWWU6jeNVleBuv7bA+f8IY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Krzysztof Zach , Jonathan Cameron , Davidlohr Bueso , Dan Williams , Sasha Levin Subject: [PATCH 5.18 551/879] cxl/pci: Make cxl_dvsec_ranges() failure not fatal to cxl_pci Date: Tue, 7 Jun 2022 19:01:09 +0200 Message-Id: <20220607165018.860048093@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220607165002.659942637@linuxfoundation.org> References: <20220607165002.659942637@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dan Williams [ Upstream commit 36bfc6ad508af38f212cf5a38147d867fb3f80a8 ] cxl_dvsec_ranges(), the helper for enumerating the presence of an active legacy CXL.mem configuration on a CXL 2.0 Memory Expander, is not fatal for cxl_pci because there is still value to enable mailbox operations even if CXL.mem operation is disabled. Recall that the reason cxl_pci does this initialization and not cxl_mem is to preserve the useful property (for unit testing) that cxl_mem is cxl_memdev + mmio generic, and does not require access to a 'struct pci_dev' to issue config cycles. Update 'struct cxl_endpoint_dvsec_info' to carry either a positive number of non-zero size legacy CXL DVSEC ranges, or the negative error code from __cxl_dvsec_ranges() in its @ranges member. Reported-by: Krzysztof Zach Fixes: 560f78559006 ("cxl/pci: Retrieve CXL DVSEC memory info") Reviewed-by: Jonathan Cameron Reviewed-by: Davidlohr Bueso Link: https://lore.kernel.org/r/164730735869.3806189.4032428192652531946.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Signed-off-by: Sasha Levin --- drivers/cxl/pci.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index c4941a3ca6a8..bb92853c3b93 100644 --- a/drivers/cxl/pci.c +++ b/drivers/cxl/pci.c @@ -462,13 +462,18 @@ static int wait_for_media_ready(struct cxl_dev_state *cxlds) return 0; } -static int cxl_dvsec_ranges(struct cxl_dev_state *cxlds) +/* + * Return positive number of non-zero ranges on success and a negative + * error code on failure. The cxl_mem driver depends on ranges == 0 to + * init HDM operation. + */ +static int __cxl_dvsec_ranges(struct cxl_dev_state *cxlds, + struct cxl_endpoint_dvsec_info *info) { - struct cxl_endpoint_dvsec_info *info = &cxlds->info; struct pci_dev *pdev = to_pci_dev(cxlds->dev); + int hdm_count, rc, i, ranges = 0; struct device *dev = &pdev->dev; int d = cxlds->cxl_dvsec; - int hdm_count, rc, i; u16 cap, ctrl; if (!d) { @@ -545,10 +550,17 @@ static int cxl_dvsec_ranges(struct cxl_dev_state *cxlds) }; if (size) - info->ranges++; + ranges++; } - return 0; + return ranges; +} + +static void cxl_dvsec_ranges(struct cxl_dev_state *cxlds) +{ + struct cxl_endpoint_dvsec_info *info = &cxlds->info; + + info->ranges = __cxl_dvsec_ranges(cxlds, info); } static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) @@ -617,10 +629,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) if (rc) return rc; - rc = cxl_dvsec_ranges(cxlds); - if (rc) - dev_warn(&pdev->dev, - "Failed to get DVSEC range information (%d)\n", rc); + cxl_dvsec_ranges(cxlds); cxlmd = devm_cxl_add_memdev(cxlds); if (IS_ERR(cxlmd)) -- 2.35.1