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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3CC6DC433F5 for ; Tue, 24 May 2022 17:05:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239806AbiEXRFd (ORCPT ); Tue, 24 May 2022 13:05:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54538 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237243AbiEXRFV (ORCPT ); Tue, 24 May 2022 13:05:21 -0400 Received: from NAM10-MW2-obe.outbound.protection.outlook.com (mail-mw2nam10on2082.outbound.protection.outlook.com [40.107.94.82]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EAC197983D; Tue, 24 May 2022 10:05:20 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Al4KdHw4U9I2K1YQ6XYLFLPiueAYqwzn2Z8NwyksjtfpAioAdfyWIzN5TXgS/HZ7Bz1BJ+Ia4bp48Y7t6mE2zz507Vt7dS/gfTmcNEkMfAYRpy7a7XLClMVwqYlKDbBfJJrl82pehRokW84ai1awUv32+wIwwEtKSYXLEWY4F+RWK+mw9gdS5j6sZinhR4FLI3Fo770JoIBefAIj8vSzZpNWrd/6yDUFBKatWxYWRLBdExhaIAloJilW7eymRb/Z2wVWx1myhTmskG1gq3sl66EtNMeEi/L4vJRZh0v2pG5cz9Fgjr6Ws8vAOXmo5Ym4wwpqghRh7G0fIRNLICe21Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=RKlaon0w9WJiUFAvv4xgquJqPEvrmdkURbVT1zaLDOo=; b=gcwypWQqEP6qOtGgskVhlAegG9ivxQDZn638T8YjE/B4l4HrUfSpiz62y0IXMr94EUdrCRdy/xzukPrFqhwBeSmbv11Zm7sZ5MoHe+8CELSkiDYKBtFzIMeMAuXxrWYUfb9G+xk9CVCDDOxXBQbpn/rbOu9746f4QITYjnbJ9iH9i3KrUbdPJp+haJaKBRKId06OQ+nTwx0DaoS0SzmdrVXdSULaGmBZo4SwNxF467FkFX/Dn5ZhxbxLJR9xgQ20smtpIGcsvltnwyzwIzvSIfzaLru3gMc8xq9UCaYjCuIGR0dP4uV7f5WSDxRIk9mKPRxw7aze8xi2X0wEnt01ew== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 165.204.84.17) smtp.rcpttodomain=opensource.wdc.com smtp.mailfrom=amd.com; dmarc=pass (p=quarantine sp=quarantine pct=100) action=none header.from=amd.com; dkim=none (message not signed); arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=RKlaon0w9WJiUFAvv4xgquJqPEvrmdkURbVT1zaLDOo=; b=ZPl9HrLg4yBUuh0/zPp+ymtFuwqpmAI86zDlXpAM5I7V0kgInpNVWc1waDUHUSYvB+3f/uArXM3tIlCYCnuGeNwe7pHQW2LtgY3EqfnQWs+Lln0drGFejMcMZBNbyDqWucxxv3ufArvoj/3qC+K8tB3djrWS7mzoG3hTmI1H2Jg= Received: from BN0PR04CA0093.namprd04.prod.outlook.com (2603:10b6:408:ec::8) by SN1PR12MB2367.namprd12.prod.outlook.com (2603:10b6:802:26::31) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5273.16; Tue, 24 May 2022 17:05:17 +0000 Received: from BN8NAM11FT059.eop-nam11.prod.protection.outlook.com (2603:10b6:408:ec:cafe::a1) by BN0PR04CA0093.outlook.office365.com (2603:10b6:408:ec::8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5273.21 via Frontend Transport; Tue, 24 May 2022 17:05:17 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 165.204.84.17) smtp.mailfrom=amd.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=amd.com; Received-SPF: Pass (protection.outlook.com: domain of amd.com designates 165.204.84.17 as permitted sender) receiver=protection.outlook.com; client-ip=165.204.84.17; helo=SATLEXMB04.amd.com; pr=C Received: from SATLEXMB04.amd.com (165.204.84.17) by BN8NAM11FT059.mail.protection.outlook.com (10.13.177.120) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.20.5273.14 via Frontend Transport; Tue, 24 May 2022 17:05:17 +0000 Received: from AUS-LX-MLIMONCI.amd.com (10.180.168.240) by SATLEXMB04.amd.com (10.181.40.145) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 24 May 2022 12:05:14 -0500 From: Mario Limonciello To: Damien Le Moal CC: "open list:LIBATA SUBSYSTEM (Serial and Parallel ATA drivers)" , open list , , Mario Limonciello Subject: [PATCH 3/3] ahci: Document the loss of hotplug by new LPM policy Date: Tue, 24 May 2022 12:05:08 -0500 Message-ID: <20220524170508.563-4-mario.limonciello@amd.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220524170508.563-1-mario.limonciello@amd.com> References: <20220524170508.563-1-mario.limonciello@amd.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Originating-IP: [10.180.168.240] X-ClientProxiedBy: SATLEXMB03.amd.com (10.181.40.144) To SATLEXMB04.amd.com (10.181.40.145) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 9ea70655-8d65-4178-21cf-08da3da793cf X-MS-TrafficTypeDiagnostic: SN1PR12MB2367:EE_ X-Microsoft-Antispam-PRVS: X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: bwVCN3CgnhoO8nXvFphBDOwW1zj8RJNeM0LQxYYos/BWlL6wcjW/Vm5FB5Cxk1HzdbVe2oVQbi35bup9GlQhl/R31MCjcbIvEvcj2g2UZddhtgapDIt5mn+niBy71+SXUjSxQZz6/PAVW4xKePsiuZF05erGv/XgE25q0Yu78PrDzXN5Ne4cCSkpWzOKvHXWVLV19hjb4qboGo+nbNH+3TQ7eUrZp6kfcbgU4Sr1vRAFOf8NGgxCGSShNoRlrPfSb+p2xD7QwGXqdxwcEymkDTNk7dY+ywbkQtY3SsWIDqcUxnFPdBMzS0WlVq7monrEWCXKGWjr6dH3IU5qja7Eqs0UdcCWOSDda7tCrBtZrIDVdLhHzm2sAZB9I621lIJhpiCHJ6qvvQ5jtPcWE6w+dFsXHjBC7g6DiTQPZKbgHsdXXiNhjQPpij6kDS1ZrbpxMzAR53jLTxE/Gdc1HLxE6b8ALLDQGot1mtWl0gTKjUhN2B3tqG/1VHglNBSdhdcyDSv/JzyK925BlrtbQiBZ1qlJaO49Gdv0Hya4FaCC/SWjJ5jles+RjthAob0wrNeWs0QHzKh5cMTyaVF1WtBlIsazXR5uKQ8s8xUmt9Luc7pPEhNadJZxuYVYKgJY27DKmOGJZ49EI0lhLJW1W5+JAu/dGRP+cs/goP7zwNSdlR4UNj629VQhTVi2/F2VXZVThv/OV5fYWZJiejqp0qfbA513F573u/Fhe7yK0IdWgbdxTf13SXd3qiBkZx/d+YSRYibsEQmBY+7BYPcQo87E90H7LUUmineMDSKIcXi9kjKk1zlLk6H5fgfa6P+f3guL8ACa81y5OOR0eczn4YE3Gw== X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:SATLEXMB04.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230001)(4636009)(36840700001)(40470700004)(46966006)(40460700003)(86362001)(186003)(426003)(70206006)(5660300002)(47076005)(2616005)(966005)(54906003)(7696005)(26005)(6666004)(1076003)(36756003)(508600001)(82310400005)(36860700001)(70586007)(336012)(16526019)(2906002)(8676002)(316002)(4326008)(6916009)(81166007)(8936002)(44832011)(83380400001)(356005)(36900700001);DIR:OUT;SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 May 2022 17:05:17.4223 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 9ea70655-8d65-4178-21cf-08da3da793cf X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[SATLEXMB04.amd.com] X-MS-Exchange-CrossTenant-AuthSource: BN8NAM11FT059.eop-nam11.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN1PR12MB2367 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Per AHCI spec v1.3.1, "7.3 Native Hot Plug Support", once LPM is enabled hotplug support needs to be disabled. The LPM code always followed this and disabled the port when no drives were connected, but as more machines will be exposed to this code it might be an unexpected behavior to some users. Add a note to parameter documentation to explain the new behavior. Link: https://bugs.launchpad.net/bugs/1971576 Signed-off-by: Mario Limonciello --- Documentation/admin-guide/kernel-parameters.txt | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 9e6bd212004d..4dcd9a3ba4a5 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -279,6 +279,13 @@ 3 => Medium power with Device Initiated PM enabled 4 => Minimum power + NOTE: Enabling LPM when no drive is connected will disable + the port which means hotplug will not work. + + If hotplug is an important use case, this can be modified + at runtime by changing + /sys/module/ahci/parameters/lpm_policy + ALSA [HW,ALSA] See Documentation/sound/alsa-configuration.rst -- 2.34.1