From patchwork Wed May 26 10:14:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: ameynarkhede03 X-Patchwork-Id: 12281195 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 X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 E1060C2B9F7 for ; Wed, 26 May 2021 10:14:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C758A61360 for ; Wed, 26 May 2021 10:14:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233911AbhEZKQT (ORCPT ); Wed, 26 May 2021 06:16:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59700 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233891AbhEZKQL (ORCPT ); Wed, 26 May 2021 06:16:11 -0400 Received: from mail-pg1-x536.google.com (mail-pg1-x536.google.com [IPv6:2607:f8b0:4864:20::536]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 77485C061574; Wed, 26 May 2021 03:14:39 -0700 (PDT) Received: by mail-pg1-x536.google.com with SMTP id 6so543210pgk.5; Wed, 26 May 2021 03:14:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=+kjX7vYmWzq1R7BiwbLx/rhOeELktigh7hpXVvkPMNY=; b=Kc62qixb7dfoIVA0r72e1gyF4+gAgQF2SHyd1a9L6gWrzisLbu/LIRmjV7G9d5oIYl r1GoFUECGM5dSEMe3pegNQ6oVUIUKw38TA0mWOnfw61WGoaPPVrh3/T4MBNeqfih0tmG BqUYr+7CwGoRGrJv5IGSBgvFp8ZyuD8Il/1b2TTARqxtQReAjavl8MH2KxSlXV44Q7D/ 1nvGhXzAF8tCgwPWaq3ngNVICUIvOa2TymWUXJhlGdFL8zo39j3YE1FEEjM0WQgnmkvl smIspmbjgi1tUML8maQh+KjwgbLTr15hWKY6+1TSSh4YxrD/x5bZJuUI6lfpBuU1dk6Q B9xg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=+kjX7vYmWzq1R7BiwbLx/rhOeELktigh7hpXVvkPMNY=; b=SR2FumBe3GnfRsg/i5eHgZsk0JlNCchE4iyxyOlTU6WITV47YAxjKcI74Z2O1zu0ac AmWcLbnT2Q6UJG2/tN7NO30ft+DIewBRQSV23cvOOJ21mc27Icmcn9qtOG+Vpimewq91 IcCvnrDdP6Be/awD/qEG0SLnq43xp+xMaz3m2LRBmgFqKKIJD1UovMMO3fHfICC02+vM H62aeUt5vEYVsEYD5HzkIg0GV4tsujs6z8pUASQKdL8fyiDgqoXEvpugEnkVTsz59ExC Uoljhd3I3vm5mQ6P7U9ubERZey3LUHKj6eeiS8bLVlgFuYn+vpcS5a/A1YMccyUp9nBD XSzA== X-Gm-Message-State: AOAM531CZl7GGTtTNlC2huSDt2JNIlMNxX+ki17Glxx8HlQEiKRXJP2f 3WGI+1KVN9NdRJNthRxI17k= X-Google-Smtp-Source: ABdhPJxlFWUhQojQqlHx+vSpFlxlKtAO1T+xcBFll70bQ2ATBzvxJiLSMF3BK9Z4Yx2kYk9q1SccYQ== X-Received: by 2002:a63:d709:: with SMTP id d9mr24393260pgg.337.1622024079086; Wed, 26 May 2021 03:14:39 -0700 (PDT) Received: from localhost.localdomain ([103.248.31.164]) by smtp.googlemail.com with ESMTPSA id c191sm15662614pfc.94.2021.05.26.03.14.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 26 May 2021 03:14:38 -0700 (PDT) From: Amey Narkhede To: Bjorn Helgaas Cc: alex.williamson@redhat.com, Raphael Norwitz , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, kw@linux.com, Shanker Donthineni , Sinan Kaya Subject: [PATCH v3 5/7] PCI: Add support for a function level reset based on _RST method Date: Wed, 26 May 2021 15:44:01 +0530 Message-Id: <20210526101403.108721-6-ameynarkhede03@gmail.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210526101403.108721-1-ameynarkhede03@gmail.com> References: <20210526101403.108721-1-ameynarkhede03@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Shanker Donthineni The _RST is a standard method specified in the ACPI specification. It provides a function level reset when it is described in the acpi_device context associated with PCI-device. Implement a new reset function pci_dev_acpi_reset() for probing RST method and execute if it is defined in the firmware. The ACPI binding information is available only after calling device_add(), so move pci_init_reset_methods() to end of the pci_device_add(). The default priority of the acpi reset is set to below device-specific and above hardware resets. Signed-off-by: Shanker Donthineni Reviewed-by: Sinan Kaya --- drivers/pci/pci.c | 30 ++++++++++++++++++++++++++++++ drivers/pci/probe.c | 2 +- include/linux/pci.h | 2 +- 3 files changed, 32 insertions(+), 2 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index fad209c5f..1d859b100 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5076,6 +5076,35 @@ static void pci_dev_restore(struct pci_dev *dev) err_handler->reset_done(dev); } +/** + * pci_dev_acpi_reset - do a function level reset using _RST method + * @dev: device to reset + * @probe: check if _RST method is included in the acpi_device context. + */ +static int pci_dev_acpi_reset(struct pci_dev *dev, int probe) +{ +#ifdef CONFIG_ACPI + acpi_handle handle = ACPI_HANDLE(&dev->dev); + + /* Return -ENOTTY if _RST method is not included in the dev context */ + if (!handle || !acpi_has_method(handle, "_RST")) + return -ENOTTY; + + /* Return 0 for probe phase indicating that we can reset this device */ + if (probe) + return 0; + + /* Invoke _RST() method to perform a function level reset */ + if (ACPI_FAILURE(acpi_evaluate_object(handle, "_RST", NULL, NULL))) { + pci_warn(dev, "Failed to reset the device\n"); + return -EINVAL; + } + return 0; +#else + return -ENOTTY; +#endif +} + /* * The ordering for functions in pci_reset_fn_methods * is required for reset_methods byte array defined @@ -5083,6 +5112,7 @@ static void pci_dev_restore(struct pci_dev *dev) */ const struct pci_reset_fn_method pci_reset_fn_methods[] = { { &pci_dev_specific_reset, .name = "device_specific" }, + { &pci_dev_acpi_reset, .name = "acpi" }, { &pcie_reset_flr, .name = "flr" }, { &pci_af_flr, .name = "af_flr" }, { &pci_pm_reset, .name = "pm" }, diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 4764e031a..d4becd6ff 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2403,7 +2403,6 @@ static void pci_init_capabilities(struct pci_dev *dev) pci_rcec_init(dev); /* Root Complex Event Collector */ pcie_report_downtraining(dev); - pci_init_reset_methods(dev); } /* @@ -2494,6 +2493,7 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus) dev->match_driver = false; ret = device_add(&dev->dev); WARN_ON(ret < 0); + pci_init_reset_methods(dev); } struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn) diff --git a/include/linux/pci.h b/include/linux/pci.h index e9603d638..9bec3c616 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -49,7 +49,7 @@ PCI_STATUS_SIG_TARGET_ABORT | \ PCI_STATUS_PARITY) -#define PCI_RESET_METHODS_NUM 5 +#define PCI_RESET_METHODS_NUM 6 /* * The PCI interface treats multi-function devices as independent