From patchwork Fri Sep 15 12:01:36 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Ilpo_J=C3=A4rvinen?= X-Patchwork-Id: 13386964 X-Patchwork-Delegate: bhelgaas@google.com 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 B04B8EE6457 for ; Fri, 15 Sep 2023 12:03:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234444AbjIOMDJ (ORCPT ); Fri, 15 Sep 2023 08:03:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55688 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232836AbjIOMDJ (ORCPT ); Fri, 15 Sep 2023 08:03:09 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0F37B2722; Fri, 15 Sep 2023 05:02:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1694779365; x=1726315365; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=vDsDIHqtLtfNmUG3Y8t5VDuHkp8RJgeZagGcp/a8iuA=; b=PD0Pbphd+cTrXrBvdDVaWpF4myBOn9G1gLBVBDyobay5CxrmEKWRdZ2Q uNwoCAp//+s9Mu8gny17P13Q9g0MdpUipcjuqUFBn9n2LI7YoLFsy8ozP rJirOo8WNVjdm9ZRKwIlA7oQ5pxpvCnLnuge/hEqB0qSVvHWXR4wtKK8X RhJXm8RZxIlHbB+ER9GUxQDyGPe3BlsHkwXfZ3CVaKNtKlUNTq7sXpa7d f3VAKlTLy6HE9/MGAF0HZnq895dqlZJek1tMBRnX7YQ339zDQl0MyzYBz IUGpuhzuWtwDfmZyQ0C7IZiD98i4iHHZti+uNtqCG0s0QaBHAvsZmsaSL g==; X-IronPort-AV: E=McAfee;i="6600,9927,10833"; a="378146017" X-IronPort-AV: E=Sophos;i="6.02,149,1688454000"; d="scan'208";a="378146017" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Sep 2023 05:02:22 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10833"; a="774292848" X-IronPort-AV: E=Sophos;i="6.02,149,1688454000"; d="scan'208";a="774292848" Received: from srdoo-mobl1.ger.corp.intel.com (HELO ijarvine-mobl2.ger.corp.intel.com) ([10.252.38.99]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Sep 2023 05:02:14 -0700 From: =?utf-8?q?Ilpo_J=C3=A4rvinen?= To: linux-pci@vger.kernel.org, Bjorn Helgaas , Lorenzo Pieralisi , Rob Herring , =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= , Lukas Wunner , Alexandru Gagniuc , Krishna chaitanya chundru , Srinivas Pandruvada , "Rafael J . Wysocki" , linux-pm@vger.kernel.org, Dennis Dalessandro , Jason Gunthorpe , Leon Romanovsky , linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Alex Deucher , Daniel Lezcano , Amit Kucheria , Zhang Rui , =?utf-8?q?Ilpo_J=C3=A4rvinen?= Subject: [PATCH v2 04/10] drm/IB/hfi1: Use RMW accessors for changing LNKCTL2 Date: Fri, 15 Sep 2023 15:01:36 +0300 Message-Id: <20230915120142.32987-5-ilpo.jarvinen@linux.intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230915120142.32987-1-ilpo.jarvinen@linux.intel.com> References: <20230915120142.32987-1-ilpo.jarvinen@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Don't assume that only the driver would be accessing LNKCTL2. In the case of upstream (parent), the driver does not even own the device it's changing the registers for. Use RMW capability accessors which do proper locking to avoid losing concurrent updates to the register value. This change is also useful as a cleanup. Suggested-by: Lukas Wunner Signed-off-by: Ilpo Järvinen --- drivers/infiniband/hw/hfi1/pcie.c | 30 ++++++++---------------------- 1 file changed, 8 insertions(+), 22 deletions(-) diff --git a/drivers/infiniband/hw/hfi1/pcie.c b/drivers/infiniband/hw/hfi1/pcie.c index 08732e1ac966..60a177f52eb5 100644 --- a/drivers/infiniband/hw/hfi1/pcie.c +++ b/drivers/infiniband/hw/hfi1/pcie.c @@ -1212,14 +1212,11 @@ int do_pcie_gen3_transition(struct hfi1_devdata *dd) (u32)lnkctl2); /* only write to parent if target is not as high as ours */ if ((lnkctl2 & PCI_EXP_LNKCTL2_TLS) < target_vector) { - lnkctl2 &= ~PCI_EXP_LNKCTL2_TLS; - lnkctl2 |= target_vector; - dd_dev_info(dd, "%s: ..new link control2: 0x%x\n", __func__, - (u32)lnkctl2); - ret = pcie_capability_write_word(parent, - PCI_EXP_LNKCTL2, lnkctl2); + ret = pcie_capability_clear_and_set_word(parent, PCI_EXP_LNKCTL2, + PCI_EXP_LNKCTL2_TLS, + target_vector); if (ret) { - dd_dev_err(dd, "Unable to write to PCI config\n"); + dd_dev_err(dd, "Unable to change PCI target speed\n"); return_error = 1; goto done; } @@ -1228,22 +1225,11 @@ int do_pcie_gen3_transition(struct hfi1_devdata *dd) } dd_dev_info(dd, "%s: setting target link speed\n", __func__); - ret = pcie_capability_read_word(dd->pcidev, PCI_EXP_LNKCTL2, &lnkctl2); + ret = pcie_capability_clear_and_set_word(dd->pcidev, PCI_EXP_LNKCTL2, + PCI_EXP_LNKCTL2_TLS, + target_vector); if (ret) { - dd_dev_err(dd, "Unable to read from PCI config\n"); - return_error = 1; - goto done; - } - - dd_dev_info(dd, "%s: ..old link control2: 0x%x\n", __func__, - (u32)lnkctl2); - lnkctl2 &= ~PCI_EXP_LNKCTL2_TLS; - lnkctl2 |= target_vector; - dd_dev_info(dd, "%s: ..new link control2: 0x%x\n", __func__, - (u32)lnkctl2); - ret = pcie_capability_write_word(dd->pcidev, PCI_EXP_LNKCTL2, lnkctl2); - if (ret) { - dd_dev_err(dd, "Unable to write to PCI config\n"); + dd_dev_err(dd, "Unable to change PCI target speed\n"); return_error = 1; goto done; }