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 X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9714FC433E0 for ; Wed, 24 Jun 2020 19:11:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7B68320702 for ; Wed, 24 Jun 2020 19:11:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=intel-com.20150623.gappssmtp.com header.i=@intel-com.20150623.gappssmtp.com header.b="in62/pK4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404900AbgFXTLG (ORCPT ); Wed, 24 Jun 2020 15:11:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37888 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404434AbgFXTLE (ORCPT ); Wed, 24 Jun 2020 15:11:04 -0400 Received: from mail-ed1-x541.google.com (mail-ed1-x541.google.com [IPv6:2a00:1450:4864:20::541]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1D6A2C061573 for ; Wed, 24 Jun 2020 12:11:04 -0700 (PDT) Received: by mail-ed1-x541.google.com with SMTP id m21so2298521eds.13 for ; Wed, 24 Jun 2020 12:11:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=HUy3SYLieHUYRrbu7ksz+DDx5NoSGhvtwAWM7BS+NcQ=; b=in62/pK4305qlruXOrme3JoGaFZsG+ngmdYPd6qQJVPMZU8zi45J/cdtrR/1S2nDpG osC789ZrUhTlXbnv7LgWIfcNPZ+ugiqfFG98EnA6GebisxGlzNr6DE/YYjikoTyjpTr6 dzESw5Tk70JPsArLMfUSCMZmv4fCVRQauL8U50UEeeTPu7ml5UcziaUxfOow1iLRtOE9 g3KIkUWDlvL4VHx0ultb5v4HHmoFF5GBabUMOWbywjy9cYRAsAWsYMhAumd5XKngyrLj x1ScTaJ71iWX60kuFWHkQlJK56tNx/8L3F9ZHkDXvkYZVgaBDVCDP3QzFahIOfXx7tbl dc1Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=HUy3SYLieHUYRrbu7ksz+DDx5NoSGhvtwAWM7BS+NcQ=; b=nOq9ssojY0tjeFho8RC0uG7DfdBxkndK5T5U5MV1mW47CCYNxn95QwJ5gJ/p6pGU0T o7UAn9dTQPBVrf5pyshrCIw6PF4YCI/yw1XO0XwBq1sGUHi6CsBFKej0lgMKwVerr62O SEwljP4iSyl3Xdy1DcE5jb67jSSdPCs9q+0eH+OerZni84gaUjNwKPn9PcDUNzHIasl3 cuHm9ATaJNinObzxJDsJ8Qxs42GPO7KXh5djkyQwR0aX/QLhItFnVlBJJGTihjwdLU18 0F1fCewyOD8Cx3MBugUsDzwwfSiNjP0vzgpJse4PGMYNvFjQergxadj/YzoWMkcUagEK qIgQ== X-Gm-Message-State: AOAM530oqWPySZgtQfnki0G+yojNn0ICrsQK+DiUtyCIcxa85kKPClch y6nY0MQZQrOtk7GuzIsjpuDK9N0YcKFJ0RKoDwWJ3w== X-Google-Smtp-Source: ABdhPJwTc+VdGxK7PxA2A2Hb2Q/oOwneukaqMN+TiIWLM8FMg1nGLcl6/OQXIozSlGxncNmyGtKZ6GK3+EL+fh+R4Sw= X-Received: by 2002:aa7:d6c1:: with SMTP id x1mr27574990edr.154.1593025862677; Wed, 24 Jun 2020 12:11:02 -0700 (PDT) MIME-Version: 1.0 References: <20200428003214.3764-1-david.e.box@linux.intel.com> <20200612204820.20111-1-david.e.box@linux.intel.com> <12d36fdcdbcf438dd3aac7769e8366afd9d5aa1a.camel@linux.intel.com> In-Reply-To: <12d36fdcdbcf438dd3aac7769e8366afd9d5aa1a.camel@linux.intel.com> From: Dan Williams Date: Wed, 24 Jun 2020 12:10:50 -0700 Message-ID: Subject: Re: [PATCH V2 0/2] nvme: Add support for ACPI StorageD3Enable property To: David Box Cc: "N, Shyjumon" , "Rafael J. Wysocki" , Len Brown , Bjorn Helgaas , Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg , Linux ACPI , Linux Kernel Mailing List , linux-pci@vger.kernel.org, linux-nvme@lists.infradead.org Content-Type: text/plain; charset="UTF-8" Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On Wed, Jun 24, 2020 at 11:55 AM David E. Box wrote: > > Friendly reminder. Thanks. Are you looking for this to be merged by ACPI with an NVMe ack, or merged by NVMe with an ACPI ack? It sometimes helps to be explicit to break the log jam. > > David > > On Fri, 2020-06-12 at 13:48 -0700, David E. Box wrote: > > This patch set implements a solution for a BIOS hack used on some > > currently > > shipping Intel systems to address issues with power management policy > > decisions concerning PCIe NVMe drives. Some newer Intel platforms, > > like > > some Comet Lake systems, require that PCIe devices use D3 when doing > > suspend-to-idle in order to allow the platform to realize maximum > > power > > savings. This is particularly needed to support ATX power supply > > shutdown > > on desktop systems. In order to ensure this happens for root ports > > with > > storage devices, Microsoft apparently created this ACPI _DSD property > > as a > > way to override their driver policy. To my knowledge this property > > has not > > been discussed with the NVME specification body. > > > > Though the solution is not ideal, it addresses a problem that also > > affects > > Linux since the NVMe driver's default policy of using NVMe APST > > during > > suspend-to-idle would lead to higher power consumption for these > > platforms. > > > > Patch 1 provides a symbol in the PCI/ACPI layer to read the property. > > Patch 2 uses the symbol in the NVMe driver to select D3 as a quirk if > > set. > > > > Changes from V2: > > - Export the pci_acpi_storage_d3 function for use by drivers as > > needed instead of modifying the pci header. > > - Add missing put on acpi device handle. > > - Add 'noacpi' module parameter to allow undoing this change. > > - Add info message that this is a platform quirk. > > > > David E. Box (2): > > PCI: Add ACPI StorageD3Enable _DSD support > > drivers/nvme: Add support for ACPI StorageD3Enable property > > > > drivers/acpi/property.c | 3 +++ > > drivers/nvme/host/pci.c | 14 ++++++++++ > > drivers/pci/pci-acpi.c | 59 > > +++++++++++++++++++++++++++++++++++++++++ > > include/linux/pci.h | 2 ++ > > 4 files changed, 78 insertions(+) > > >