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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id AD325CCA462 for ; Fri, 16 Oct 2026 05:38:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ktqFSsAx52niNcMbY6VRLuj3WY+yJAl8EZhfxOg24+s=; b=AA6b0VLrR+7FSRKka5pE+gQhST Soyr2hWa6ocJ5IAdDCS8VjvQUFodIjKdI2ctHfA/DgTfGoaWRi2/lxyE73N7TC6zRC5tdP2qLtFUx atyYoj9jzn5DQKyedccZiZyDbVN0XFv8wNFsrG3q5bxytb2wt3PYJ2MekAJjGSb4RbzdLl3mkZGv7 0S3JW8lifdF8shUhzogcBYbCJsXREHtPSeoGG5+3+uOqfsmNy3WnDJCrj45q6bynJkFHvOsSljEZD H5oJMSV68hVd1HgSjO6PaZHt0IcsUfl7D9C21oPxy1mty3mjI/MJVViuQu52ompvFkXfGuR0jVWv2 BMUJQQjg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xHaeS-000000022jH-0xnc; Fri, 16 Oct 2026 05:38:44 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1xHaeR-000000022iY-2n93; Fri, 16 Oct 2026 05:38:43 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id BBAB7600D4; Fri, 16 Oct 2026 05:38:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B45551F000C4; Fri, 16 Oct 2026 05:38:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792129122; bh=ktqFSsAx52niNcMbY6VRLuj3WY+yJAl8EZhfxOg24+s=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=TGISrgXLsZT/CTjeLsAIaY1W0qIJ+pKBQSG0YeThNt4I/0JCvBaoFTZAPXWGmHCad FsWo1l2SSLWIKzSvLrhQpv5RbEyMiS+3pLkdKeUqdI9Uk4YLk/L/vJ2HvpJaGqnDDO +xukVVIwCLfi9Vf2MFtSwhWzIhF20wpuJ+19jo3+tYu6fOGJZ1jb3P3d7137vUmDcE VXwdaCVqJW2wbuIlM5oNG8z7Xoa2OlFQ1P8YDaXGTBofxnC5/nd93f02C2zlRsXGwa Es0sLy0Tre9LPf3lT0Es5b2CEG0RwsvGfI7IcwB7oqKiYzEIxG7NnvW+SDXs2+7s7s tytdwblQwdoDA== Date: Fri, 16 Oct 2026 11:08:29 +0530 From: Manivannan Sadhasivam To: Bjorn Helgaas Cc: Bjorn Helgaas , Lorenzo Pieralisi , Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Rob Herring , Nirmal Patel , Jonathan Derrick , Jeff Johnson , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-wireless@vger.kernel.org, ath12k@lists.infradead.org, ath11k@lists.infradead.org, ath10k@lists.infradead.org, Krishna Chaitanya Chundru , Qiang Yu , Ilpo =?utf-8?B?SsOkcnZpbmVu?= Subject: Re: [PATCH v3 1/8] PCI/ASPM: Always disable ASPM when driver requests it Message-ID: References: <20260708-pci-aspm-fix-v3-1-6bd72451746e@kernel.org> <20261015230714.GA1802070@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20261015230714.GA1802070@bhelgaas> X-BeenThere: ath10k@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "ath10k" Errors-To: ath10k-bounces+ath10k=archiver.kernel.org@lists.infradead.org On Thu, Oct 15, 2026 at 06:07:14PM -0500, Bjorn Helgaas wrote: > On Wed, Jul 08, 2026 at 04:30:15PM +0200, Manivannan Sadhasivam wrote: > > From: Ilpo Järvinen > > > > PCI core/ASPM service driver allows controlling ASPM state through > > pci_disable_link_state() API. It was decided earlier (see the Link > > below), to not allow ASPM changes when OS does not have control over it > > but only log a warning about the problem 'commit 2add0ec14c25 ("PCI/ASPM: > > Warn when driver asks to disable ASPM, but we can't do it")'. > > > > A number of drivers have added workarounds to force ASPM off with own > > writes into the Link Control Register (some even with comments > > explaining why PCI core does not disable it under some circumstances). > > According to the comments, some drivers require ASPM to be off for > > reliable operation. > > > > Having custom ASPM handling in drivers is problematic because the state > > kept in the ASPM service driver is not updated by the changes made > > outside the link state management API. > > > > As the first step to address this issue, make pci_disable_link_state() > > to unconditionally disable ASPM so the motivation for drivers to come > > up with custom ASPM handling code is eliminated. > > > > To fully take advantage of the ASPM handling core provides, the drivers > > that need to quirk ASPM have to be altered depend on PCIEASPM and the > > custom ASPM code is removed. This is to be done separately. As PCIEASPM > > is already behind EXPERT, it should be no problem to limit disabling it > > for configurations that do not require touching ASPM. > > > > Make pci_disable_link_state() function comment to comply kerneldoc > > formatting while changing the description. > > > > Link: https://lore.kernel.org/all/CANUX_P3F5YhbZX3WGU-j1AGpbXb_T9Bis2ErhvKkFMtDvzatVQ@mail.gmail.com/ > > Link: https://lore.kernel.org/all/20230511131441.45704-1-ilpo.jarvinen@linux.intel.com/ > > Signed-off-by: Ilpo Järvinen > > [mani: commit message fixup] > > Signed-off-by: Manivannan Sadhasivam > > I was a little confused about the provenance of this patch. It > *looks* like it should have been posted somewhere by Ilpo and > something tweaked by Mani when applying, but none of the links above > are a posting of this patch. I dug around and found > https://lore.kernel.org/linux-pci/20230918131103.24119-4-ilpo.jarvinen@linux.intel.com/, > and this patch looks like basically the aspm.c part of it, so I assume > that should probably be the https://patch.msgid.link/? > Ilpo shared this patch during the review of v1 of this series: https://lore.kernel.org/linux-pci/52baf40b-41ed-2588-7817-4d8cd859e0d1@linux.intel.com/ > To fix the provenance and the "Drivers can controlling" typo mentioned > by Ilpo, I replaced this with just the aspm.c changes from > https://lore.kernel.org/linux-pci/20230918131103.24119-4-ilpo.jarvinen@linux.intel.com/ > and added the CONFIG_PCIEASPM dependency to the commit log. The code > change is the same. > This looks good to me. - Mani -- மணிவண்ணன் சதாசிவம்