From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sinan Kaya Subject: [PATCH v2 2/2] PCI/ACPI: allow _OSC presence to be optional for PCI Date: Fri, 10 Aug 2018 04:32:12 +0000 Message-ID: <1533875532-24954-2-git-send-email-okaya@kernel.org> References: <1533875532-24954-1-git-send-email-okaya@kernel.org> Return-path: In-Reply-To: <1533875532-24954-1-git-send-email-okaya@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: linux-pci@vger.kernel.org Cc: Sinan Kaya , Bjorn Helgaas , "Rafael J. Wysocki" , Len Brown , "open list:ACPI" , open list List-Id: linux-acpi@vger.kernel.org ACPI Spec 6.0 Section 6.2.11.3 OSC Implementation Example for PCI Host Bridge Devices: For a host bridge device that originates a PCI Express hierarchy, the _OSC interface defined in this section is required. For a host bridge device that originates a PCI/PCI-X bus hierarchy, inclusion of an _OSC object is optional. Allow PCI host bridges to bail out silently if _OSC is not found. Signed-off-by: Sinan Kaya Reported-by: Michael Kelley --- drivers/acpi/pci_root.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index e465e72..707aafc 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -421,7 +421,8 @@ acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req) } EXPORT_SYMBOL(acpi_pci_osc_control_set); -static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm) +static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm, + bool is_pcie) { u32 support, control, requested; acpi_status status; @@ -455,10 +456,15 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm) decode_osc_support(root, "OS supports", support); status = acpi_pci_osc_support(root, support); if (ACPI_FAILURE(status)) { + *no_aspm = 1; + + /* _OSC is optional for PCI host bridges */ + if ((status == AE_NOT_FOUND) && !is_pcie) + return; + dev_info(&device->dev, "_OSC failed (%s)%s\n", acpi_format_exception(status), pcie_aspm_support_enabled() ? "; disabling ASPM" : ""); - *no_aspm = 1; return; } @@ -534,6 +540,7 @@ static int acpi_pci_root_add(struct acpi_device *device, acpi_handle handle = device->handle; int no_aspm = 0; bool hotadd = system_state == SYSTEM_RUNNING; + bool is_pcie; root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL); if (!root) @@ -591,7 +598,8 @@ static int acpi_pci_root_add(struct acpi_device *device, root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle); - negotiate_os_control(root, &no_aspm); + is_pcie = strcmp(acpi_device_hid(device), "PNP0A08") == 0; + negotiate_os_control(root, &no_aspm, is_pcie); /* * TBD: Need PCI interface for enumeration/configuration of roots. -- 2.7.4 From mboxrd@z Thu Jan 1 00:00:00 1970 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=-3.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,T_DKIMWL_WL_HIGH,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 C94DEC46464 for ; Fri, 10 Aug 2018 04:32:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8005A223E4 for ; Fri, 10 Aug 2018 04:32:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="2QYU4IqN" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8005A223E4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727336AbeHJHA0 (ORCPT ); Fri, 10 Aug 2018 03:00:26 -0400 Received: from mail.kernel.org ([198.145.29.99]:43520 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725907AbeHJHAZ (ORCPT ); Fri, 10 Aug 2018 03:00:25 -0400 Received: from sinanubuntu1604.mkjiurmyylmellclgttazegk5f.bx.internal.cloudapp.net (unknown [104.41.132.238]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 00877223E6; Fri, 10 Aug 2018 04:32:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1533875539; bh=ep03PYapCeVjr8SjK5mkrUXq5d9312OAgTtYKLqhMXo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2QYU4IqNfSyU6NTWh5WjNyAg1R/ZdotrFdCZ+nMKGu3g92st8NUKeCC/FLJ9XFGYI 16/ihYLikB/e6ZzrEnz4ZsQitDnmXqLI9J5OObJWWHfrLCE4pOG/sOVEFljLlFqwrO Xr9SZK6oHOUSzpjIiGL0B8JvA9ZGNWV7wI4dKp3A= From: Sinan Kaya To: linux-pci@vger.kernel.org Cc: Sinan Kaya , Bjorn Helgaas , "Rafael J. Wysocki" , Len Brown , linux-acpi@vger.kernel.org (open list:ACPI), linux-kernel@vger.kernel.org (open list) Subject: [PATCH v2 2/2] PCI/ACPI: allow _OSC presence to be optional for PCI Date: Fri, 10 Aug 2018 04:32:12 +0000 Message-Id: <1533875532-24954-2-git-send-email-okaya@kernel.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1533875532-24954-1-git-send-email-okaya@kernel.org> References: <1533875532-24954-1-git-send-email-okaya@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ACPI Spec 6.0 Section 6.2.11.3 OSC Implementation Example for PCI Host Bridge Devices: For a host bridge device that originates a PCI Express hierarchy, the _OSC interface defined in this section is required. For a host bridge device that originates a PCI/PCI-X bus hierarchy, inclusion of an _OSC object is optional. Allow PCI host bridges to bail out silently if _OSC is not found. Signed-off-by: Sinan Kaya Reported-by: Michael Kelley --- drivers/acpi/pci_root.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index e465e72..707aafc 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -421,7 +421,8 @@ acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req) } EXPORT_SYMBOL(acpi_pci_osc_control_set); -static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm) +static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm, + bool is_pcie) { u32 support, control, requested; acpi_status status; @@ -455,10 +456,15 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm) decode_osc_support(root, "OS supports", support); status = acpi_pci_osc_support(root, support); if (ACPI_FAILURE(status)) { + *no_aspm = 1; + + /* _OSC is optional for PCI host bridges */ + if ((status == AE_NOT_FOUND) && !is_pcie) + return; + dev_info(&device->dev, "_OSC failed (%s)%s\n", acpi_format_exception(status), pcie_aspm_support_enabled() ? "; disabling ASPM" : ""); - *no_aspm = 1; return; } @@ -534,6 +540,7 @@ static int acpi_pci_root_add(struct acpi_device *device, acpi_handle handle = device->handle; int no_aspm = 0; bool hotadd = system_state == SYSTEM_RUNNING; + bool is_pcie; root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL); if (!root) @@ -591,7 +598,8 @@ static int acpi_pci_root_add(struct acpi_device *device, root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle); - negotiate_os_control(root, &no_aspm); + is_pcie = strcmp(acpi_device_hid(device), "PNP0A08") == 0; + negotiate_os_control(root, &no_aspm, is_pcie); /* * TBD: Need PCI interface for enumeration/configuration of roots. -- 2.7.4