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 CEBB5C433FE for ; Fri, 4 Feb 2022 23:02:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377809AbiBDXCk (ORCPT ); Fri, 4 Feb 2022 18:02:40 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:49942 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1377814AbiBDXCj (ORCPT ); Fri, 4 Feb 2022 18:02:39 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 56FEFB83965; Fri, 4 Feb 2022 23:02:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 93B8CC004E1; Fri, 4 Feb 2022 23:02:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1644015757; bh=o2VFGLNW0Dd7KKuBrN5hzNBG6Tf7nQ6064dDe55xopM=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=YITiFfCaOnsMORKmtcDiLlpaowUD1vcxapDSZGot81Xn2yBP/n1t5x4jw29h7PZbo K613Tj0B17M3B+u99SIIFfbIIYtelgvhXOChiSgWBpIJdqccJ7rnZ1zMqiIFV9iEMF 8NpN+4pYMMjJZcIkZceWCixMPzGTShey+U0gH1eeaLVPS50jXLBQ6gY6UEx6HdpRpj wJbnxK0XlnlCLx1/pjlPVZCtsyMMm6unSUYbExbgv00xLDxxucmBxvxg4Al5HZse6R BTkWhRLb8mpbDPHXSfnt3/gGcnDOs82HVncumTXsV971a1TS+LV9KEwogD/ELDxlAy 0a6dJVKz/NEng== Date: Fri, 4 Feb 2022 17:02:34 -0600 From: Bjorn Helgaas To: Vidya Sagar Cc: "Kenneth R. Crudup" , bhelgaas@google.com, lorenzo.pieralisi@arm.com, hkallweit1@gmail.com, wangxiongfeng2@huawei.com, mika.westerberg@linux.intel.com, kai.heng.feng@canonical.com, chris.packham@alliedtelesis.co.nz, yangyicong@hisilicon.com, treding@nvidia.com, jonathanh@nvidia.com, abhsahu@nvidia.com, sagupta@nvidia.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, kthota@nvidia.com, mmaddireddy@nvidia.com, sagar.tv@gmail.com Subject: Re: [PATCH V1] PCI/ASPM: Save/restore L1SS Capability for suspend/resume Message-ID: <20220204230234.GA226601@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <708b746c-1715-9d64-5a59-55c9ad81bd0a@nvidia.com> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Feb 02, 2022 at 09:47:06AM +0530, Vidya Sagar wrote: > On 2/2/2022 3:55 AM, Kenneth R. Crudup wrote: > > On Wed, 2 Feb 2022, Vidya Sagar wrote: > > > BTW, I see that the ASPM L1SS capability is supported by only > > > two endpoints viz. KIOXIA's NVMe drive and Realtek's Card > > > reader. None of the root ports seem to have the support. So, I'm > > > wondering how was it even getting enabled in the first place > > > earlier? > > > > > (OR) > > > > > was it the case that L1SS sub-states were never enabled earlier > > > also and the issue was occurring without having ASPM L1SS > > > enabled? (but with only L0s and L1 enabled??) > > > > I'm not proficient enough in PCIe to be able to be sure of the > > answers to those- what can/could I do to determine this? > > Nothing at this point, but could you please confirm that you are > using the same system as before? if that is the case, then, I'm not > sure how is it possible that the earlier patch which is also for > saving/restoring L1SS registers could affect a system that doesn't > even support L1SS. > > Bjorn, any thoughts on this? Do we have a theory on what might have caused the regression before? Or at least something that is different this time around? There's been a lot of discussion on this thread, so I'm going to ignore this patch for now. If you think it's good to go, please post it again with the relevant Tested-bys and a note about why we think it should work this time when it didn't last time. Bjorn > > > Also, I see that from 'before' and 'after' logs that for both > > > NVMe and Card reader and their corresponding root ports, none of > > > the ASPM states are enabled (not even L0s or L1). > > > Did you set the policy to 'powersupersave' before hibernating > > > the system? > > > > Yeah: > > > > CONFIG_PCIEASPM_POWER_SUPERSAVE=y > > > > My laptop loses ~1.5%/hr in S3; I was trying anything I could to reduce that, > > if possible. > > > > -Kenny > > > > -- > > Kenneth R. Crudup / Sr. SW Engineer, Scott County Consulting, Orange County CA > >