From patchwork Tue Jan 12 04:02:04 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Victor Ding X-Patchwork-Id: 361523 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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=unavailable 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 C9D89C43381 for ; Tue, 12 Jan 2021 04:03:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 99FB022A83 for ; Tue, 12 Jan 2021 04:03:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728424AbhALEC4 (ORCPT ); Mon, 11 Jan 2021 23:02:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43328 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728412AbhALEC4 (ORCPT ); Mon, 11 Jan 2021 23:02:56 -0500 Received: from mail-pj1-x104a.google.com (mail-pj1-x104a.google.com [IPv6:2607:f8b0:4864:20::104a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4ACD1C06179F for ; Mon, 11 Jan 2021 20:02:16 -0800 (PST) Received: by mail-pj1-x104a.google.com with SMTP id q21so617282pjp.3 for ; Mon, 11 Jan 2021 20:02:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=ak768gEI6XCH+aPGM5U6EpkG7B0YhsCWJJw1G4ZyE7I=; b=JG+Sg8xWVV6o2H7jEpk7k4T+BYMj0g9b6yD/Ot9mOHxD3cId9PvCBaP793TPOW6UDE NemddI4QWvvzitpZfeFW+h/oZk7T6Jnj+EEIilx9OvKxUllf+a15pi4wBluJwif15orG lxt0Iwhipfxrk6ZW89+/Fvs9cjOHvOjWU7z5Ydl+jyjAJMe1yjselzRW72578Bx2Fyqc d3fSSxw4Snb1Eucb/fUPnADWmIUQDqlRl6E6WwlguCH12WUI4466mfh2+DLUIKH0GubQ Z+ijve1yEtXLZp0i1ZdOM1OSbmUX0fmUjCnlyPY9JvwvvDhbZnup8zgujXBoFuyz5geq 1Dyg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=ak768gEI6XCH+aPGM5U6EpkG7B0YhsCWJJw1G4ZyE7I=; b=U6Nj6DSPxpG8bVW1UjVf1yh6KrDiDLuDjXXkLHq0AkGLqVfXrANV6k3tobECt6vSZl 5htr21Xxfr8AEJc4bSqKsDG6gHzipvDoMT7hjhgrPq0HjFbF2pT0GFKlRMh97CgLzNaB ZQKs6DHovwDtG2uXg70Ll7AK4PD0k0B669bJ/3nZdlwJ4d1N8/Icx1tnk9h0jJ5yLCd3 RbxyGbk8L427I3HKPOpAcMpNMLe96eusxeCubjwktkej56a6kqzqmgSHnn0qERaE1DCV kE1zxBsUorgnXav/OWfr0sgCaRxev1XH1V6g+fqp08iQh+YgRSeyVdR4xZF5lWQ7Zm/d GSlA== X-Gm-Message-State: AOAM531/S1xyhtu5CVFIlV706gZVeaC0W2QzUM027RrYCV+ejjoOW4iM W25nZXylrHsKyOqJ1y71YwiXQa5rReEmXFeC X-Google-Smtp-Source: ABdhPJyeGpHSwrKQpN/leiMW8w46NVzHLITPTcbviWLsyHqYnfuKcC5BbfnSxl+8REx+Rif+d0Rdxchqd99GuCMG Sender: "victording via sendgmr" X-Received: from victording.c.googlers.com ([fda3:e722:ac3:10:24:72f4:c0a8:65c7]) (user=victording job=sendgmr) by 2002:a17:902:c144:b029:dc:292e:a8a1 with SMTP id 4-20020a170902c144b02900dc292ea8a1mr3103608plj.13.1610424135755; Mon, 11 Jan 2021 20:02:15 -0800 (PST) Date: Tue, 12 Jan 2021 04:02:04 +0000 In-Reply-To: <20210112040205.4117303-1-victording@google.com> Message-Id: <20210112040146.1.I9aa2b9dd39a6ac9235ec55a8c56020538aa212fb@changeid> Mime-Version: 1.0 References: <20210112040205.4117303-1-victording@google.com> X-Mailer: git-send-email 2.30.0.284.gd98b1dd5eaa7-goog Subject: [PATCH 1/2] PCI/ASPM: Disable ASPM until its LTR and L1ss state is restored From: Victor Ding To: Ulf Hansson , Adrian Hunter Cc: Ben Chuang , Bjorn Helgaas , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-mmc@vger.kernel.org, Victor Ding , Alex Levin , Bjorn Helgaas , Kai-Heng Feng , "Saheed O. Bolarinwa" , Sean Paul , Sukumar Ghorai , Yicong Yang Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org Right after powering up, the device may have ASPM enabled; however, its LTR and/or L1ss controls may not be in the desired states; hence, the device may enter L1.2 undesirably and cause resume performance penalty. This is especially problematic if ASPM related control registers are modified before a suspension. Therefore, ASPM should disabled until its LTR and L1ss states are fully restored. Signed-off-by: Victor Ding --- drivers/pci/pci.c | 11 +++++++++++ drivers/pci/pci.h | 2 ++ drivers/pci/pcie/aspm.c | 2 +- 3 files changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index eb323af34f1e..428de433f2e6 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1660,6 +1660,17 @@ void pci_restore_state(struct pci_dev *dev) if (!dev->state_saved) return; + /* + * Right after powering up, the device may have ASPM enabled; + * however, its LTR and/or L1ss controls may not be in the desired + * states; as a result, the device may enter L1.2 undesirably and + * cause resume performance penalty. + * Therefore, ASPM is disabled until its LTR and L1ss states are + * fully restored. + * (enabling ASPM is part of pci_restore_pcie_state) + */ + pcie_config_aspm_dev(dev, 0); + /* * Restore max latencies (in the LTR capability) before enabling * LTR itself (in the PCIe capability). diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index e9ea5dfaa3e0..f774bd6d2555 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -564,6 +564,7 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev); void pcie_aspm_exit_link_state(struct pci_dev *pdev); void pcie_aspm_pm_state_change(struct pci_dev *pdev); void pcie_aspm_powersave_config_link(struct pci_dev *pdev); +void pcie_config_aspm_dev(struct pci_dev *pdev, u32 val); void pci_save_aspm_l1ss_state(struct pci_dev *dev); void pci_restore_aspm_l1ss_state(struct pci_dev *dev); #else @@ -571,6 +572,7 @@ static inline void pcie_aspm_init_link_state(struct pci_dev *pdev) { } static inline void pcie_aspm_exit_link_state(struct pci_dev *pdev) { } static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev) { } static inline void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { } +static inline void pcie_config_aspm_dev(struct pci_dev *pdev, u32 val) { } static inline void pci_save_aspm_l1ss_state(struct pci_dev *dev) { } static inline void pci_restore_aspm_l1ss_state(struct pci_dev *dev) { } #endif diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index a08e7d6dc248..45535b4e1595 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -778,7 +778,7 @@ void pci_restore_aspm_l1ss_state(struct pci_dev *dev) pci_write_config_dword(dev, aspm_l1ss + PCI_L1SS_CTL2, *cap++); } -static void pcie_config_aspm_dev(struct pci_dev *pdev, u32 val) +void pcie_config_aspm_dev(struct pci_dev *pdev, u32 val) { pcie_capability_clear_and_set_word(pdev, PCI_EXP_LNKCTL, PCI_EXP_LNKCTL_ASPMC, val);