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 2EEDAC77B61 for ; Tue, 25 Apr 2023 05:58:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233290AbjDYF6e (ORCPT ); Tue, 25 Apr 2023 01:58:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35458 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233255AbjDYF6d (ORCPT ); Tue, 25 Apr 2023 01:58:33 -0400 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8AFFB768A; Mon, 24 Apr 2023 22:58:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1682402312; x=1713938312; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=se7YPSlb4h1MC4CMmAIT2KU5ZaEL8RqWu41fI7ro+m0=; b=Ej85k1WHrsZzn9ZSsbPKL905G1yGchbNsac4ln6dcXpVBMGyk4KP7Nax 5I2jYsjBWB6aVysDCDVMlJZOmd6x6MNaymMDONfYpaXY2NJ4KLSq8FXAH +kicONGKjZ0HodnR1CsQ7fTVsUB73mUbiOXerrZoQd9mGlbG21OGvimpc z1SYjFZpMcO/TFvEz3MzTxQ7PwSJIltRu1V40/JqgxuXUlCLFJSRBnzEQ 1HcprUDRL3t+WSgDlkDIiodHXgUX/Jh4JeeZgBlujPZF0c4Y2fD6yYQBy Rt4MfGJL68OHaz/t8L7wUGuICTUDDwHAaSutmvTNA8Jus8TF4qVrfVtiq g==; X-IronPort-AV: E=McAfee;i="6600,9927,10690"; a="344147885" X-IronPort-AV: E=Sophos;i="5.99,224,1677571200"; d="scan'208";a="344147885" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Apr 2023 22:58:32 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10690"; a="867763728" X-IronPort-AV: E=Sophos;i="5.99,224,1677571200"; d="scan'208";a="867763728" Received: from jsagoe-mobl1.amr.corp.intel.com (HELO [10.251.8.47]) ([10.251.8.47]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Apr 2023 22:58:30 -0700 Message-ID: Date: Mon, 24 Apr 2023 22:58:28 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Firefox/102.0 Thunderbird/102.10.0 Subject: Re: [PATCH v4 2/3] PCI/AER: Disable AER interrupt on suspend Content-Language: en-US To: Kai-Heng Feng Cc: bhelgaas@google.com, mika.westerberg@linux.intel.com, koba.ko@canonical.com, Mahesh J Salgaonkar , Oliver O'Halloran , linuxppc-dev@lists.ozlabs.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org References: <20230424055249.460381-1-kai.heng.feng@canonical.com> <20230424055249.460381-2-kai.heng.feng@canonical.com> <97260e8b-1892-49a5-3792-0e3c28378fc0@linux.intel.com> From: Sathyanarayanan Kuppuswamy In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Hi, On 4/24/23 10:55 PM, Kai-Heng Feng wrote: > On Tue, Apr 25, 2023 at 7:47 AM Sathyanarayanan Kuppuswamy > wrote: >> >> >> >> On 4/23/23 10:52 PM, Kai-Heng Feng wrote: >>> PCIe service that shares IRQ with PME may cause spurious wakeup on >>> system suspend. >>> >>> PCIe Base Spec 5.0, section 5.2 "Link State Power Management" states >>> that TLP and DLLP transmission is disabled for a Link in L2/L3 Ready >>> (D3hot), L2 (D3cold with aux power) and L3 (D3cold), so we don't lose >>> much here to disable AER during system suspend. >>> >>> This is very similar to previous attempts to suspend AER and DPC [1], >>> but with a different reason. >>> >>> [1] https://lore.kernel.org/linux-pci/20220408153159.106741-1-kai.heng.feng@canonical.com/ >>> Link: https://bugzilla.kernel.org/show_bug.cgi?id=216295 >>> >>> Reviewed-by: Mika Westerberg >>> Signed-off-by: Kai-Heng Feng >>> --- >> >> IIUC, you encounter AER errors during the suspend/resume process, which >> results in AER IRQ. Because AER and PME share an IRQ, it is regarded as a >> spurious wake-up IRQ. So to fix it, you want to disable AER reporting, >> right? > > Yes. That's exactly what happened. > >> >> It looks like it is harmless to disable the AER during the suspend/resume >> path. But, I am wondering why we get these errors? Did you check what errors >> you get during the suspend/resume path? Are these errors valid? > > I really don't know. I think it's similar to the reasoning in commit > b07461a8e45b ("PCI/AER: Clear error status registers during > enumeration and restore"): "AER errors might be recorded when > powering-on devices. These errors can be ignored, ...". > For this case, it happens when powering-off the device (D3cold) via > turning off power resources. Got it. Reviewed-by: Kuppuswamy Sathyanarayanan > > Kai-Heng > >> >> >>> drivers/pci/pcie/aer.c | 22 ++++++++++++++++++++++ >>> 1 file changed, 22 insertions(+) >>> >>> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c >>> index 1420e1f27105..9c07fdbeb52d 100644 >>> --- a/drivers/pci/pcie/aer.c >>> +++ b/drivers/pci/pcie/aer.c >>> @@ -1356,6 +1356,26 @@ static int aer_probe(struct pcie_device *dev) >>> return 0; >>> } >>> >>> +static int aer_suspend(struct pcie_device *dev) >>> +{ >>> + struct aer_rpc *rpc = get_service_data(dev); >>> + struct pci_dev *pdev = rpc->rpd; >>> + >>> + aer_disable_irq(pdev); >>> + >>> + return 0; >>> +} >>> + >>> +static int aer_resume(struct pcie_device *dev) >>> +{ >>> + struct aer_rpc *rpc = get_service_data(dev); >>> + struct pci_dev *pdev = rpc->rpd; >>> + >>> + aer_enable_irq(pdev); >>> + >>> + return 0; >>> +} >>> + >>> /** >>> * aer_root_reset - reset Root Port hierarchy, RCEC, or RCiEP >>> * @dev: pointer to Root Port, RCEC, or RCiEP >>> @@ -1420,6 +1440,8 @@ static struct pcie_port_service_driver aerdriver = { >>> .service = PCIE_PORT_SERVICE_AER, >>> >>> .probe = aer_probe, >>> + .suspend = aer_suspend, >>> + .resume = aer_resume, >>> .remove = aer_remove, >>> }; >>> >> >> -- >> Sathyanarayanan Kuppuswamy >> Linux Kernel Developer -- Sathyanarayanan Kuppuswamy Linux Kernel Developer