From patchwork Mon Sep 18 13:10:55 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Ilpo_J=C3=A4rvinen?= X-Patchwork-Id: 13389919 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A6AFF137C for ; Mon, 18 Sep 2023 15:46:23 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5A0C0CF8; Mon, 18 Sep 2023 08:45:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1695051920; x=1726587920; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=uEKrgp0fS4TcV/kqj/T1ibXnz9U6nSS/hcSxBB6l/C0=; b=fQjsiB6vONTRlk5HZosldvkskKXZ2MTyw1KqGM3O3eFuh+jVIf6/8ul4 Rzi241HaWnxbMJgnRQya5Vf5HZBP40Y5/Jj4XJPboRdRKlTbqJ0qr0KOd nCbLZK7sWH5N93txZXAqS2jwkyz0Y8GoxizUBigNMg5QCESzbT+8Rj8Qv 4YBOb63OSFvCwj72KYi0Jj4Vw0D+W+P2od8ZDz/C7ghlZjHdP8TrGwjnD vm6PTGbzxAKuGfkYpabIXNG137gcRf/MI5I7SpYfdHbXbsnn5eCB+evOX q6Dk4OQs5qbi37fN5XaOTMg5h66s6jQeP0qCtpkaAkAWdIuseFiDPqdxX A==; X-IronPort-AV: E=McAfee;i="6600,9927,10837"; a="446113406" X-IronPort-AV: E=Sophos;i="6.02,156,1688454000"; d="scan'208";a="446113406" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Sep 2023 06:12:36 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10837"; a="811342150" X-IronPort-AV: E=Sophos;i="6.02,156,1688454000"; d="scan'208";a="811342150" Received: from nprotaso-mobl1.ccr.corp.intel.com (HELO ijarvine-mobl2.ger.corp.intel.com) ([10.252.49.156]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Sep 2023 06:12:30 -0700 From: =?utf-8?q?Ilpo_J=C3=A4rvinen?= To: linux-pci@vger.kernel.org, Bjorn Helgaas , Lorenzo Pieralisi , Rob Herring , =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= , Lukas Wunner , "Rafael J . Wysocki" , Heiner Kallweit , Emmanuel Grumbach , linux-kernel@vger.kernel.org, Bjorn Helgaas Cc: ath10k@lists.infradead.org, ath11k@lists.infradead.org, ath12k@lists.infradead.org, intel-wired-lan@lists.osuosl.org, linux-arm-kernel@lists.infradead.org, linux-bluetooth@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-rdma@vger.kernel.org, linux-wireless@vger.kernel.org, netdev@vger.kernel.org, =?utf-8?q?Ilpo_J?= =?utf-8?q?=C3=A4rvinen?= Subject: [PATCH v2 05/13] PCI/ASPM: Add pci_enable_link_state() Date: Mon, 18 Sep 2023 16:10:55 +0300 Message-Id: <20230918131103.24119-6-ilpo.jarvinen@linux.intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230918131103.24119-1-ilpo.jarvinen@linux.intel.com> References: <20230918131103.24119-1-ilpo.jarvinen@linux.intel.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net pci_disable_link_state() lacks a symmetric pair. Some drivers want to disable ASPM during certain phases of their operation but then re-enable it later on. If pci_disable_link_state() is made for the device, there is currently no way to re-enable the states that were disabled. Add pci_enable_link_state() to remove ASPM states from the state disable mask. Signed-off-by: Ilpo Järvinen --- drivers/pci/pcie/aspm.c | 42 +++++++++++++++++++++++++++++++++++++++++ include/linux/pci.h | 2 ++ 2 files changed, 44 insertions(+) diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index 91dc95aca90f..f45d18d47c20 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -1117,6 +1117,48 @@ int pci_disable_link_state(struct pci_dev *pdev, int state) } EXPORT_SYMBOL(pci_disable_link_state); +/** + * pci_enable_link_state - Re-enable device's link state + * @pdev: PCI device + * @state: ASPM link states to re-enable + * + * Enable device's link state that were previously disable so the link is + * allowed to enter the specific states. Note that if the BIOS didn't grant + * ASPM control to the OS, this does nothing because we can't touch the + * LNKCTL register. + * + * Return: 0 or a negative errno. + */ +int pci_enable_link_state(struct pci_dev *pdev, int state) +{ + struct pcie_link_state *link = pcie_aspm_get_link(pdev); + + if (!link) + return -EINVAL; + /* + * A driver requested that ASPM be enabled on this device, but + * if we don't have permission to manage ASPM (e.g., on ACPI + * systems we have to observe the FADT ACPI_FADT_NO_ASPM bit and + * the _OSC method), we can't honor that request. + */ + if (aspm_disabled) { + pci_warn(pdev, "can't enable ASPM; OS doesn't have ASPM control\n"); + return -EPERM; + } + + mutex_lock(&aspm_lock); + link->aspm_disable &= ~pci_link_state_mask(state); + pcie_config_aspm_link(link, policy_to_aspm_state(link)); + + if (state & PCIE_LINK_STATE_CLKPM) + link->clkpm_disable = 0; + pcie_set_clkpm(link, policy_to_clkpm_state(link)); + mutex_unlock(&aspm_lock); + + return 0; +} +EXPORT_SYMBOL(pci_enable_link_state); + /** * pci_set_default_link_state - Set the default device link state * @pdev: PCI device diff --git a/include/linux/pci.h b/include/linux/pci.h index 3c24ca164104..844d09230264 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1776,11 +1776,13 @@ extern bool pcie_ports_native; int pci_disable_link_state(struct pci_dev *pdev, int state); int pci_disable_link_state_locked(struct pci_dev *pdev, int state); #ifdef CONFIG_PCIEASPM +int pci_enable_link_state(struct pci_dev *pdev, int state); int pci_set_default_link_state(struct pci_dev *pdev, int state); void pcie_no_aspm(void); bool pcie_aspm_support_enabled(void); bool pcie_aspm_enabled(struct pci_dev *pdev); #else +static inline int pci_enable_link_state(struct pci_dev *pdev, int state) { return -EOPNOTSUPP; } static inline int pci_set_default_link_state(struct pci_dev *pdev, int state) { return 0; } static inline void pcie_no_aspm(void) { }