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 E4C2DC64EC4 for ; Tue, 7 Feb 2023 20:35:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230231AbjBGUff (ORCPT ); Tue, 7 Feb 2023 15:35:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34744 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229559AbjBGUff (ORCPT ); Tue, 7 Feb 2023 15:35:35 -0500 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 01BBD37B78; Tue, 7 Feb 2023 12:35:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1675802134; x=1707338134; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=COq+zJrBQ8UVb2EFH4kB5bj/6NQTPCXFj3H5Q0d+tFc=; b=VCqpHaWInq9xU6cebpa8tvkdXBrLbgjr5c6jMXqQbuPkVghIbPdfI+Ek ma3pdaRQx2TSpwTmrRHsIGYDG5IA9ACWhP+s5e5YtzWKRJx5lMkjjI02s r6DZsUvrSfWke5UgSucFwqZjndecjTUDrq3YBvx2TGQa8d+h6XEMJcSYc rWMUiRKqKEN9XKmQbvaVwpGAFoxc7ejvKx9rzU1vQ9cxKoHlAC8t60Ari Q/5Zsd0Hgrin17F52RHqYLW0CgcTUxlOHEoquSY8Ewr2hh2RLJwmhj5Ss 0KzjR0csDW6mKrYumjrs1hAhVagRUh7buBpijga6x/+Qg/FHCXQzQpd6m g==; X-IronPort-AV: E=McAfee;i="6500,9779,10614"; a="330911432" X-IronPort-AV: E=Sophos;i="5.97,279,1669104000"; d="scan'208";a="330911432" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Feb 2023 12:35:33 -0800 X-IronPort-AV: E=McAfee;i="6500,9779,10614"; a="666977840" X-IronPort-AV: E=Sophos;i="5.97,279,1669104000"; d="scan'208";a="666977840" Received: from djiang5-mobl3.amr.corp.intel.com (HELO [10.212.98.37]) ([10.212.98.37]) by orsmga002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Feb 2023 12:35:32 -0800 Message-ID: <664b54a6-699d-9c48-5cd7-d8fd7d54d165@intel.com> Date: Tue, 7 Feb 2023 13:35:31 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Firefox/102.0 Thunderbird/102.6.0 Subject: Re: [PATCH 11/18] PCI: Export pcie_get_width() using the code from sysfs PCI link width show function Content-Language: en-US To: Bjorn Helgaas Cc: linux-cxl@vger.kernel.org, linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org, dan.j.williams@intel.com, ira.weiny@intel.com, vishal.l.verma@intel.com, alison.schofield@intel.com, rafael@kernel.org, bhelgaas@google.com, robert.moore@intel.com References: <20230206224338.GA2256550@bhelgaas> From: Dave Jiang In-Reply-To: <20230206224338.GA2256550@bhelgaas> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On 2/6/23 3:43 PM, Bjorn Helgaas wrote: > On Mon, Feb 06, 2023 at 01:51:01PM -0700, Dave Jiang wrote: >> Move the logic in current_link_width_show() to a common function and export >> that functiuon as pcie_get_width() to allow other drivers to to retrieve >> the current negotiated link width. > > s/a common function and export that functiuon and export that functiuon as// > > I don't see the module caller of this, so not clear on why it needs to > be exported. You are right. I think I was using it before I found pcie_bandwidth_available() call. I will drop. > >> Signed-off-by: Dave Jiang >> --- >> drivers/pci/pci-sysfs.c | 9 +-------- >> drivers/pci/pci.c | 20 ++++++++++++++++++++ >> include/linux/pci.h | 1 + >> 3 files changed, 22 insertions(+), 8 deletions(-) >> >> diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c >> index 0217bb5ca8fa..139096c39380 100644 >> --- a/drivers/pci/pci-sysfs.c >> +++ b/drivers/pci/pci-sysfs.c >> @@ -215,15 +215,8 @@ static ssize_t current_link_width_show(struct device *dev, >> struct device_attribute *attr, char *buf) >> { >> struct pci_dev *pci_dev = to_pci_dev(dev); >> - u16 linkstat; >> - int err; >> >> - err = pcie_capability_read_word(pci_dev, PCI_EXP_LNKSTA, &linkstat); >> - if (err) >> - return -EINVAL; >> - >> - return sysfs_emit(buf, "%u\n", >> - (linkstat & PCI_EXP_LNKSTA_NLW) >> PCI_EXP_LNKSTA_NLW_SHIFT); >> + return sysfs_emit(buf, "%u\n", pcie_get_width(pci_dev)); >> } >> static DEVICE_ATTR_RO(current_link_width); >> >> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c >> index d0131b5623b1..0858fa2f1c2d 100644 >> --- a/drivers/pci/pci.c >> +++ b/drivers/pci/pci.c >> @@ -6235,6 +6235,26 @@ enum pci_bus_speed pcie_get_speed(struct pci_dev *dev) >> } >> EXPORT_SYMBOL(pcie_get_speed); >> >> +/** >> + * pcie_get_width - query for the PCI device's current link width >> + * @dev: PCI device to query >> + * >> + * Query the PCI device current negoiated width. >> + */ >> + >> +enum pcie_link_width pcie_get_width(struct pci_dev *dev) >> +{ >> + u16 linkstat; >> + int err; >> + >> + err = pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &linkstat); >> + if (err) >> + return PCIE_LNK_WIDTH_UNKNOWN; >> + >> + return FIELD_GET(PCI_EXP_LNKSTA_NLW, linkstat); >> +} >> +EXPORT_SYMBOL(pcie_get_width); >> + >> /** >> * pcie_bandwidth_capable - calculate a PCI device's link bandwidth capability >> * @dev: PCI device >> diff --git a/include/linux/pci.h b/include/linux/pci.h >> index 6a065986ff8f..21eca09a98e2 100644 >> --- a/include/linux/pci.h >> +++ b/include/linux/pci.h >> @@ -305,6 +305,7 @@ enum pci_bus_speed { >> >> enum pci_bus_speed pcie_get_speed(struct pci_dev *dev); >> enum pci_bus_speed pcie_get_speed_cap(struct pci_dev *dev); >> +enum pcie_link_width pcie_get_width(struct pci_dev *dev); >> enum pcie_link_width pcie_get_width_cap(struct pci_dev *dev); >> >> struct pci_vpd { >> >>