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 X-Spam-Level: X-Spam-Status: No, score=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C7F08C4167B for ; Mon, 7 Dec 2020 13:08:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7FE3F23407 for ; Mon, 7 Dec 2020 13:08:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726332AbgLGNIo (ORCPT ); Mon, 7 Dec 2020 08:08:44 -0500 Received: from mx3.molgen.mpg.de ([141.14.17.11]:46351 "EHLO mx1.molgen.mpg.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725772AbgLGNIo (ORCPT ); Mon, 7 Dec 2020 08:08:44 -0500 Received: from [192.168.0.3] (ip5f5af45d.dynamic.kabel-deutschland.de [95.90.244.93]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: pmenzel) by mx.molgen.mpg.de (Postfix) with ESMTPSA id 5328D20647B5E; Mon, 7 Dec 2020 14:08:01 +0100 (CET) To: Kuppuswamy Sathyanarayanan Cc: Bjorn Helgaas , linux-pci@vger.kernel.org, LKML , Mario Limonciello , Mika Westerberg From: Paul Menzel Subject: pci 0000:00:07.0: DPC: RP PIO log size 0 is invalid Message-ID: <084ea8e2-baae-0e2d-c60d-73fb055bdc1d@molgen.mpg.de> Date: Mon, 7 Dec 2020 14:08:00 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.1 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org [Bringing the issue up on the list in case the Linux Bugzilla is not monitored/used.] Dear Linux folks, On Intel Tiger Lake Dell laptop, Linux logs the error below [1]. [ 0.507307] pci 0000:00:07.0: DPC: RP PIO log size 0 is invalid [ 0.508835] pci 0000:00:07.2: DPC: RP PIO log size 0 is invalid $ lspci -nn -s 00:07 00:07.0 PCI bridge [0604]: Intel Corporation Tiger Lake-LP Thunderbolt PCI Express Root Port #0 [8086:9a23] (rev 01) 00:07.2 PCI bridge [0604]: Intel Corporation Tiger Lake-LP Thunderbolt PCI Express Root Port #2 [8086:9a27] (rev 01) Commit 2700561817 (PCI/DPC: Cache DPC capabilities in pci_init_capabilities()) [1] probably introduced it in Linux 5.7. What does this error actually mean? pdev->dpc_rp_log_size = (cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8; if (pdev->dpc_rp_log_size < 4 || pdev->dpc_rp_log_size > 9) { pci_err(pdev, "RP PIO log size %u is invalid\n", pdev->dpc_rp_log_size); pdev->dpc_rp_log_size = 0; } (I guess `cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE` is zero too?) Is it a firmware issue or a hardware issue? Kind regards, Paul [1]: https://bugzilla.kernel.org/show_bug.cgi?id=209943 "pci 0000:00:07.0: DPC: RP PIO log size 0 is invalid" [2]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=27005618178ef9e9bf9c42fd91101771c92e9308