From patchwork Mon Apr 24 05:52:49 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: 13221765 X-Patchwork-Delegate: bhelgaas@google.com 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 F1BF8C77B61 for ; Mon, 24 Apr 2023 06:01:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231279AbjDXGBk (ORCPT ); Mon, 24 Apr 2023 02:01:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59296 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231713AbjDXGAv (ORCPT ); Mon, 24 Apr 2023 02:00:51 -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 DFB0B3ABD; Sun, 23 Apr 2023 23:00:10 -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 7BF9541CC4; Mon, 24 Apr 2023 05:53:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canonical.com; s=20210705; t=1682315627; bh=SVJsrjo3kGR6zf7Nkbs6TXOKtUb7RWji64dwjLyjcMI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=oU8NDVHY0v/w6AGl0EDJdswZavo9YYs9SIS9j29MwskmfF8Lc4zCTyfGat9cEqgF5 9qYMSBkQgZGAFBSkkLLaZ+syIamyWBA8LXT1yvPSKAgKs2p64DGsnLi1xJxN0LYlQH xenKlugV1ZRtjFkNGtXIpXUqEFLfexqHQ45kdmfaYjf/O2nLJslDMPFKW6dFK6XSQb cwA2hGu0tM5dDsuZwVs1urh34WlAkmYuljTxXSF+lmw4XKqpXrEpPXUKcXiOKQ67DJ 3imetsMRjJfaydGmpLo9mk0yKrhavjZPhwH3lEidsrYm5BcR+U3dad/njAaU4YRnuA DkY479Z0/4dPg== 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 v4 3/3] PCI/DPC: Disable DPC interrupt during suspend Date: Mon, 24 Apr 2023 13:52:49 +0800 Message-Id: <20230424055249.460381-3-kai.heng.feng@canonical.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230424055249.460381-1-kai.heng.feng@canonical.com> References: <20230424055249.460381-1-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. 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 DPC 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 --- 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 a5d7c69b764e..98bdefde6df1 100644 --- a/drivers/pci/pcie/dpc.c +++ b/drivers/pci/pcie/dpc.c @@ -385,6 +385,30 @@ 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; @@ -400,6 +424,8 @@ 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, };