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 81FBFC3DA7D for ; Thu, 29 Dec 2022 19:07:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233774AbiL2THe (ORCPT ); Thu, 29 Dec 2022 14:07:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35340 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233710AbiL2THb (ORCPT ); Thu, 29 Dec 2022 14:07:31 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 40FDD14D21; Thu, 29 Dec 2022 11:07:30 -0800 (PST) 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 A0007B81A2F; Thu, 29 Dec 2022 19:07:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 167A1C433EF; Thu, 29 Dec 2022 19:07:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1672340847; bh=0E6p9Y5SUL0q5D3aWHHGlDH8Djpftwh4QIhYzeoCmCI=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=j2rj6t6H8AvOpUSkCfcPqquH0DJX+5k1veIzBZlYJ2X6nAcYObFDa42CAoCmvLxz1 ZGUTnzDUlehkDKO4T1Xp+MUqwSUadC4vCD6eDiKjeWPnKuiIAlPthNf0dCXt/V9ur3 YnLiIB75leaL//cH09r+5dOezAlj4xeu0upL1f0tDAT2pKJbgqGSHpC7BFhl/gNwFt uHFmMDnlzEbhYPj8p/W99+VIiH3ZGVCt+zAw1QL8GBJZUwNmLvaqL41XCUpJGCE1lz Zw3Mduk5o8+KxJhJNQ/jk4PSt7mkh27tOOSfeX30gvc0cNJi8h6oroFzPIstwsPofZ Cf5xJE1ZI+6fQ== Date: Thu, 29 Dec 2022 13:07:25 -0600 From: Bjorn Helgaas To: "Lee, Ron" Cc: "bhelgaas@google.com" , "linux-kernel@vger.kernel.org" , "linux-pci@vger.kernel.org" , "lmajczak@google.com" , "Jain, Rajat" , Ron Lee Subject: Re: [PATCH v2] PCI: Fix up L1SS capability for Intel Apollolake PCIe bridge Message-ID: <20221229190725.GA620646@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Dec 20, 2022 at 09:11:31AM +0000, Lee, Ron wrote: > > On Fri, Dec 16, 2022 at 04:29:39PM +0000, Lee, Ron wrote: > > > > On Thu, Dec 15, 2022 at 05:13:57PM +0800, Ron Lee wrote: > > Even if you haven't seen a battery life issue, I suspect you might be > > able to measure a power consumption difference if you looked for it > > and likely could see issues with manual ASPM enable/disable using > > sysfs. That might be a legitimate reason for this quirk, and if > > it is, we should mention it here. > > We can arrange the power measurement, but I doubt this quirk has > correlation to power consumption. My point is that the ASPM > behavior is not changed with or without this quirk. Makes sense. > ... > I agree that, I ever try to recover the link by traversing list, but > it didn't work and the capability list have no method to do reverse > traversal. One approach may save the whole capability list before > suspend, and check each capability link then restore the missing one > after resume. Do you think it's practical ? It is appreciated if > you could recommend a practical solution for this issue. The issue being "lspci doesn't show L1SS after suspend/resume"? Is the point of this basically to fix lspci output after suspend/resume? Or is there something else this fixes? It sounds like ASPM and L1SS works correctly after suspend/resume even without this patch? Bjorn