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 C813EC38159 for ; Fri, 20 Jan 2023 05:35:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231236AbjATFfk (ORCPT ); Fri, 20 Jan 2023 00:35:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40644 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231808AbjATFfU (ORCPT ); Fri, 20 Jan 2023 00:35:20 -0500 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C7FDF2B0B9; Thu, 19 Jan 2023 21:31:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1674192685; x=1705728685; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=bPwLT4AdfGFNjdbmHQTqlULNnRfeNCfvR5vyvMh1ppY=; b=nJQ1xKWNQ9gUpHunIYAqfJfcNUyYyAIvvfBysMIaMp0QyinPIGdlWWR8 Fo53lVqCn7LDcbXWPA7klVFnGgfGy7hmP/c6Ix3eefHsz4E90oVLewxbt ZSFsjTRNQTVKaPep4/DsyrJX6L0M2mJwF0E6KGbjkRYjmoLSfomwpzkFj VuRclqGLld5P+vS2hHONi9H8erFUGqxSeaZ6UjlODA7lchVM0Gil0ELfu dFYNTlZ4FX5NBoYPrt493C9jqUMFVIBzFVbpCoXPiUw7dsuCylr2KEus1 F6hRQ3/XYGPVTd4GFSptR18ckgYX7PWXvezZp4rXxkXsr0iaa8NAzDa9X g==; X-IronPort-AV: E=McAfee;i="6500,9779,10595"; a="411739204" X-IronPort-AV: E=Sophos;i="5.97,231,1669104000"; d="scan'208";a="411739204" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Jan 2023 21:28:46 -0800 X-IronPort-AV: E=McAfee;i="6500,9779,10595"; a="989296124" X-IronPort-AV: E=Sophos;i="5.97,231,1669104000"; d="scan'208";a="989296124" Received: from mtcooper-mobl.amr.corp.intel.com (HELO [10.212.132.108]) ([10.212.132.108]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Jan 2023 21:28:46 -0800 Message-ID: Date: Thu, 19 Jan 2023 21:28:45 -0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Firefox/102.0 Thunderbird/102.4.2 Subject: Re: [PATCH V10 0/4] Enable PCIe ASPM and LTR on select hardware Content-Language: en-US To: "David E. Box" , nirmal.patel@linux.intel.com, jonathan.derrick@linux.dev, lorenzo.pieralisi@arm.com, hch@infradead.org, kw@linux.com, robh@kernel.org, bhelgaas@google.com, michael.a.bottini@intel.com, rafael@kernel.org, me@adhityamohan.in Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org References: <20230120031522.2304439-1-david.e.box@linux.intel.com> From: Sathyanarayanan Kuppuswamy In-Reply-To: <20230120031522.2304439-1-david.e.box@linux.intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On 1/19/23 7:15 PM, David E. Box wrote: > This series adds a work around for enabling PCIe ASPM and for setting PCIe > LTR values on VMD reserved root ports on select platforms. While > configuration of these capabilities is usually done by BIOS, on these > platforms these capabilities will not be configured because the ports are > not visible to BIOS. This was part of an initial design that expected the > driver to completely handle the ports, including power management. However > on Linux those ports are still managed by the PCIe core, which has the > expectation that they adhere to device standards including BIOS > configuration, leading to this problem. > > The target platforms are Tiger Lake, Alder Lake, and Raptor Lake though the > latter has already implemented support for configuring the LTR values. > Meteor Lake is expected add BIOS ASPM support, eliminating the future need > for this work around. > > Note, the driver programs the LTRs because BIOS would also normally do this > for devices that do not set them by default. Without this, SoC power > management would be blocked on those platform. This SoC specific value is > the maximum latency required to allow the SoC to enter the deepest power > state. > > This patch addresses the following open bugzillas on VMD enabled laptops > that cannot enter low power states. > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=212355 > Link: https://bugzilla.kernel.org/show_bug.cgi?id=215063 > Link: https://bugzilla.kernel.org/show_bug.cgi?id=213717 > Looks good to me. Reviewed-by: Kuppuswamy Sathyanarayanan > David E. Box (3): > PCI: vmd: Use PCI_VDEVICE in device list > PCI: vmd: Create feature grouping for client products > PCI: vmd: Add quirk to configure PCIe ASPM and LTR > > Michael Bottini (1): > PCI/ASPM: Add pci_enable_link_state() > > drivers/pci/controller/vmd.c | 97 ++++++++++++++++++++++++++---------- > drivers/pci/pcie/aspm.c | 54 ++++++++++++++++++++ > include/linux/pci.h | 7 +++ > 3 files changed, 132 insertions(+), 26 deletions(-) > > > base-commit: 5dc4c995db9eb45f6373a956eb1f69460e69e6d4 -- Sathyanarayanan Kuppuswamy Linux Kernel Developer