From patchwork Thu May 11 13:36:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kai-Heng Feng X-Patchwork-Id: 13237973 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 095BEC7EE23 for ; Thu, 11 May 2023 13:45:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237983AbjEKNp3 (ORCPT ); Thu, 11 May 2023 09:45:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38722 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238054AbjEKNpR (ORCPT ); Thu, 11 May 2023 09:45:17 -0400 Received: from smtp-relay-canonical-1.canonical.com (smtp-relay-canonical-1.canonical.com [185.125.188.121]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E452B1BE; Thu, 11 May 2023 06:45:05 -0700 (PDT) Received: from localhost.localdomain (unknown [10.101.196.174]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-canonical-1.canonical.com (Postfix) with ESMTPSA id 2EE2C42AAF; Thu, 11 May 2023 13:37:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canonical.com; s=20210705; t=1683812227; bh=/jWMueCzoMOVJ33QBenY907j4dy6f0ZLbi4Ji6SmwJU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=LXJMcg6F9RUJNMo3hZzU+HLq5osdsPX+H9YoRDj7ckVglQpmM5hwQs0Oi0n5qLrlr YN4gdmoWuiE11eVj5sBunbh3Xf4ahe8Hc6+hmNN/E3KNizGO0Yoh0QIU/tIAkXAyLK xt392Fv5/d+W6poGq7jgdWWDe2sR2aBsgZG2p8bg26ppH1xg9j6jTglbeKPqTLQtEq iysasQd8nnIl3nBfZxUExcZmUfLV4FFdBCgVD+pJxjGUJZbO8vCh3F26VoaLGtTbEf 8y/GYPe7JXXx1FO8pyxZHzfF3Mo+PwZhIZ5NuGG11noyPVwFck9vWHLE4kbDOIvDR3 k/xyWpGVmiqtQ== From: Kai-Heng Feng To: bhelgaas@google.com Cc: mika.westerberg@linux.intel.com, koba.ko@canonical.com, sathyanarayanan.kuppuswamy@linux.intel.com, Kai-Heng Feng , Mahesh J Salgaonkar , "Oliver O'Halloran" , linuxppc-dev@lists.ozlabs.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 3/3] PCI/DPC: Disable DPC interrupt during suspend Date: Thu, 11 May 2023 21:36:09 +0800 Message-Id: <20230511133610.99759-3-kai.heng.feng@canonical.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230511133610.99759-1-kai.heng.feng@canonical.com> References: <20230511133610.99759-1-kai.heng.feng@canonical.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org PCIe service that shares IRQ with PME may cause spurious wakeup on system suspend. Since AER is conditionally disabled in previous patch, also apply the same logic to disable DPC which depends on AER to work. It's okay to disable DPC because 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), hence we don't lose much here to disable DPC during system suspend. [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 --- v5: - Wording. v4: v3: - No change. v2: - Only disable DPC IRQ. - No more check on PME IRQ#. drivers/pci/pcie/dpc.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c index 3ceed8e3de41..d2d845c20438 100644 --- a/drivers/pci/pcie/dpc.c +++ b/drivers/pci/pcie/dpc.c @@ -384,6 +384,30 @@ static int dpc_probe(struct pcie_device *dev) return status; } +static int dpc_suspend(struct pcie_device *dev) +{ + struct pci_dev *pdev = dev->port; + u16 ctl; + + pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, &ctl); + ctl &= ~PCI_EXP_DPC_CTL_INT_EN; + pci_write_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, ctl); + + return 0; +} + +static int dpc_resume(struct pcie_device *dev) +{ + struct pci_dev *pdev = dev->port; + u16 ctl; + + pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, &ctl); + ctl |= PCI_EXP_DPC_CTL_INT_EN; + pci_write_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, ctl); + + return 0; +} + static void dpc_remove(struct pcie_device *dev) { struct pci_dev *pdev = dev->port; @@ -399,6 +423,8 @@ static struct pcie_port_service_driver dpcdriver = { .port_type = PCIE_ANY_PORT, .service = PCIE_PORT_SERVICE_DPC, .probe = dpc_probe, + .suspend = dpc_suspend, + .resume = dpc_resume, .remove = dpc_remove, };