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 0791DC433EF for ; Wed, 9 Feb 2022 21:17:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233184AbiBIVRt (ORCPT ); Wed, 9 Feb 2022 16:17:49 -0500 Received: from gmail-smtp-in.l.google.com ([23.128.96.19]:44666 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233085AbiBIVRr (ORCPT ); Wed, 9 Feb 2022 16:17:47 -0500 Received: from m43-7.mailgun.net (m43-7.mailgun.net [69.72.43.7]) by lindbergh.monkeyblade.net (Postfix) with UTF8SMTPS id B4584C006939 for ; Wed, 9 Feb 2022 13:17:49 -0800 (PST) DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1644441469; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=l9IB4Qa+LqQHeEdS9Xvem4BknbivZ/qkp2XXwLsm5wQ=; b=sg8sl8dB8ru4OuY428fsvNKoEkwCxjROqMq+LJ2/8bJGeWinf8uHU+KGI/d+ntpft4V/kQM3 IGbPpeKKCgKWD2SKDHLeBATomznOrt6RNe+uV3FEsFLvxUw2oxm/SDT5J53Xt5LG/YykqBcF 5JFDEpyuFqCoNHLt/ezDRTjOX1s= X-Mailgun-Sending-Ip: 69.72.43.7 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n02.prod.us-west-2.postgun.com with SMTP id 62042f7c19d16b66a9d67c6e (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 09 Feb 2022 21:17:48 GMT Sender: nitirawa=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id DD1FBC4360C; Wed, 9 Feb 2022 21:17:47 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: nitirawa) by smtp.codeaurora.org (Postfix) with ESMTPSA id 3F84CC4338F; Wed, 9 Feb 2022 21:17:47 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Thu, 10 Feb 2022 02:47:47 +0530 From: nitirawa@codeaurora.org To: Keith Busch Cc: Vidya Sagar , rafael.j.wysocki@intel.com, keith.busch@intel.com, hch@lst.de, bhelgaas@google.com, mmaddireddy@nvidia.com, kthota@nvidia.com, sagar.tv@gmail.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: Query related to shutting down NVMe during system suspend In-Reply-To: <20220209202639.GB1616420@dhcp-10-100-145-180.wdc.com> References: <65b836cd-8d5d-b9c2-eb8f-2ee3ef46112b@nvidia.com> <20220209202639.GB1616420@dhcp-10-100-145-180.wdc.com> Message-ID: X-Sender: nitirawa@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022-02-10 01:56, Keith Busch wrote: > On Tue, Feb 01, 2022 at 09:52:28PM +0530, Vidya Sagar wrote: >> Hi Rafael & Christoph, >> My query is regarding the comment and the code that follows after it >> at >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/nvme/host/pci.c?h=v5.17-rc2#n3243 >> What I understood from it is that, there is an underlying assumption >> that the power to the devices is not removed during the suspend call. >> In the case of device-tree based platforms like Tegra194, power is >> indeed removed to the devices during suspend-resume process. Hence, >> the >> NVMe devices need to be taken through the shutdown path irrespective >> of >> whether the ASPM states are enabled or not. >> I would like to hear from you the best method to follow to achieve >> this. > > Christoph prefers to append quirks for platforms that need full device > shutdown on s2idle instead of changing the driver default. > > We use dmi matching for our current platform quirk list. I do not know > what the equivalent is for device-tree based platforms. Do you know? Hi Keith, IMO, the NVME driver is not associated with any device tree, Instead PCI driver is associated with device tree. So unlike ACPI based platform where we have platform specific DMI matching, we don't have equivalent check for DT based platform. Do we see any concern if we introduce a module param with default not set to quick suspend. For platform that need full shutdown durring resume , they can set it to quick suspend.