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=-14.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MSGID_FROM_MTA_HEADER,NICE_REPLY_A,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 8D8BBC43461 for ; Wed, 9 Sep 2020 11:42:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3B66921D43 for ; Wed, 9 Sep 2020 11:42:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amdcloud.onmicrosoft.com header.i=@amdcloud.onmicrosoft.com header.b="0q7osHpS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729851AbgIILml (ORCPT ); Wed, 9 Sep 2020 07:42:41 -0400 Received: from mail-bn8nam11on2042.outbound.protection.outlook.com ([40.107.236.42]:45280 "EHLO NAM11-BN8-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729521AbgIILf1 (ORCPT ); Wed, 9 Sep 2020 07:35:27 -0400 Received: from BL0PR12MB2577.namprd12.prod.outlook.com (2603:10b6:207:42::20) by BL0PR12MB2513.namprd12.prod.outlook.com (2603:10b6:207:4a::17) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3348.17; Wed, 9 Sep 2020 11:18:28 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=j/nu0L42PiJBSIPgAqnP2hAX1cgUwyL9hGjyOv6FtBM6hYbpElNEqeuX2SBjhi5A9C3hfwT2RPo7CKME1VE5IwezwzMY+IxSEfHXR/9i0nCkpfEFXq79Z4ujy1ct1zDcN2E+mnDyVdn34OewDeBYgNN2cUhheIZY9wdb8BZ/PwvfF1QGBa/qwPjOmY3uU3+1d7JO0QDIuKJmAuCFV4CD1rBNDcE8tI50CdQXClEQ8+B3NeS86IHzbSQU9cv3s1YxYV+X9BVZ0pShbmJFb3fxp1qC1yO+l6kabGhtw0DEtKSswpFuCDk44a+LGc3O7lnFQTk2lHl9e+o9hq64s7DMfA== 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-SenderADCheck; bh=LkimQOEDA2SAtuJdk0i0H3cyM41EypixKoicSSFeZyU=; b=QKFGzAG7CJnsl05QUVx4o2T4xdd4Yd4P9K9PxmT1zcBUq8LrwKjxIXwCK5x0FnxhxkzyxFHWCzB5fQcDsXSeQjPDI4Nosnf9JmJnvXPk/FbuBr7nzoe7ojWXrQHXDWEBIOYaDDUyjwJ95rYDr1mIUdBEmE61VuCP4P0M6QHIabQh2puOzqCH0xEEC4D7MxNTEBEqE/2cigq2Wk2wDfpNBbq1aOU0hdtbd5avE5Ps/M7EA6/OdjsLyNWGEanpnb31ikKjXqNTZwqzT4uT0Pl7SeChUcR5E/VGUmc6c8eucSjaJdMZtgUvluknO/797k55jT3jLgL+CCLSEL9E5wNgpw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=amd.com; dmarc=pass action=none header.from=amd.com; dkim=pass header.d=amd.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amdcloud.onmicrosoft.com; s=selector2-amdcloud-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=LkimQOEDA2SAtuJdk0i0H3cyM41EypixKoicSSFeZyU=; b=0q7osHpSz0W37wDyPbfz6t6rwAcyDXQnFAX9M0mN4hitZGMasHCfRQGOR99rmpBnGCFxGPoaqxPcPHlCgtK2UC30vkX+bvLZMh+09sSO3cSJk4Yuhm5YHPTeCTEb33Duv8CcgHBRCRMGXKBusz2hzS25rmzwnJHWV827EZA9FOo= Authentication-Results: kernel.org; dkim=none (message not signed) header.d=none;kernel.org; dmarc=none action=none header.from=amd.com; Received: from MN2PR12MB3775.namprd12.prod.outlook.com (2603:10b6:208:159::19) by BL0PR12MB2577.namprd12.prod.outlook.com (2603:10b6:207:42::20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3348.17; Wed, 9 Sep 2020 11:15:18 +0000 Received: from MN2PR12MB3775.namprd12.prod.outlook.com ([fe80::f8f7:7403:1c92:3a60]) by MN2PR12MB3775.namprd12.prod.outlook.com ([fe80::f8f7:7403:1c92:3a60%6]) with mapi id 15.20.3348.019; Wed, 9 Sep 2020 11:15:18 +0000 Subject: Re: [PATCH 5.8 101/186] drm/radeon: Prefer lower feedback dividers To: Greg Kroah-Hartman , linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org, Kai-Heng Feng , Alex Deucher , Sasha Levin References: <20200908152241.646390211@linuxfoundation.org> <20200908152246.531365310@linuxfoundation.org> From: =?UTF-8?Q?Christian_K=c3=b6nig?= Message-ID: <77ec0338-32a1-6379-858c-359f636a0e58@amd.com> Date: Wed, 9 Sep 2020 13:15:13 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 In-Reply-To: <20200908152246.531365310@linuxfoundation.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-ClientProxiedBy: FR2P281CA0023.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:14::10) To MN2PR12MB3775.namprd12.prod.outlook.com (2603:10b6:208:159::19) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from [IPv6:2a02:908:1252:fb60:be8a:bd56:1f94:86e7] (2a02:908:1252:fb60:be8a:bd56:1f94:86e7) by FR2P281CA0023.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:14::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3370.9 via Frontend Transport; Wed, 9 Sep 2020 11:15:16 +0000 X-Originating-IP: [2a02:908:1252:fb60:be8a:bd56:1f94:86e7] X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-HT: Tenant X-MS-Office365-Filtering-Correlation-Id: 0f4cbf93-5393-4fba-8ee4-08d854b1a201 X-MS-TrafficTypeDiagnostic: BL0PR12MB2577:|BL0PR12MB2513: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:9508; X-MS-Exchange-SenderADCheck: 1 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: Up87vEtWHoLtcEDi2I94AE6kUkUbEkhiXxRv5vQ5LWlvjVi3HuyGwbg4pmE9R4vvfH8aaZ17Zx62wnLGOiGBBeKpA30VhXbOBV3rdhwUPxb60GSr5YNMXBcRH3dji+e6nVoyk/ibBV6iobQU6DsKtGH36XE9y8nxhYGh5wLR9k3gg8qjEecyzqTHZKsYxSL2o508mQ/KIOUMaNcxISRAiF24EGEP+0IhtZlY5q8EHk96nDxbNsm2TUyjbiKAnG/wFRm62wyfMqQvVV88G3SMHsPsX0ACYqaQmEgSz5P6NvTdKHhQ/A5PNPzEGCw2VkbUg5am7sqe+hawzvyTsg1+PNRLZM0phziRBaun5MKtf0Da0e2NbXpX0OzDQBNvFgd/4aG1/u+yi9XEuS5FpewOdWm80hzcOMDVI4BqegmTc/VlbQV7BADJF9Ty4vLuzNCuXIjLLQfiWjvJwarWPa7r0mtvmy9UUssd0SrsPcDcldU= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:MN2PR12MB3775.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(4636009)(366004)(39850400004)(396003)(346002)(376002)(136003)(66556008)(45080400002)(8936002)(478600001)(2616005)(36756003)(6666004)(966005)(86362001)(5660300002)(31696002)(54906003)(186003)(16526019)(66946007)(66476007)(31686004)(8676002)(4326008)(52116002)(6486002)(316002)(83380400001)(2906002)(66574015)(154273002)(43740500002);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData: 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 X-MS-Exchange-CrossTenant-Network-Message-Id: 0f4cbf93-5393-4fba-8ee4-08d854b1a201 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB3775.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Sep 2020 11:15:17.9159 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: u02+UWhoxzBoLlI1qv3T3RlZrKNqzszbB3/WkeDalIt3V+nK9HNvI/fNS0NrwfeD X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL0PR12MB2577 X-OriginatorOrg: amd.com Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Greg, please drop that patch. It turned out to break a lot of different setups and we are going to revert it now. Thanks, Christian. Am 08.09.20 um 17:24 schrieb Greg Kroah-Hartman: > From: Kai-Heng Feng > > [ Upstream commit fc8c70526bd30733ea8667adb8b8ffebea30a8ed ] > > Commit 2e26ccb119bd ("drm/radeon: prefer lower reference dividers") > fixed screen flicker for HP Compaq nx9420 but breaks other laptops like > Asus X50SL. > > Turns out we also need to favor lower feedback dividers. > > Users confirmed this change fixes the regression and doesn't regress the > original fix. > > Fixes: 2e26ccb119bd ("drm/radeon: prefer lower reference dividers") > BugLink: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbugs.launchpad.net%2Fbugs%2F1791312&data=02%7C01%7Cchristian.koenig%40amd.com%7C9fcd8f691f97451da30608d8540e3896%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637351767352887370&sdata=KKx0nGwITXVSg5Bg7XJHbVh0T30knZDioivKxO4%2F%2BB0%3D&reserved=0 > BugLink: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbugs.launchpad.net%2Fbugs%2F1861554&data=02%7C01%7Cchristian.koenig%40amd.com%7C9fcd8f691f97451da30608d8540e3896%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637351767352897339&sdata=KWknTc75Zjw3clREsEfY6wtDcv%2F3gddeyHhrhlHN0nY%3D&reserved=0 > Reviewed-by: Christian König > Signed-off-by: Kai-Heng Feng > Signed-off-by: Alex Deucher > Signed-off-by: Sasha Levin > --- > drivers/gpu/drm/radeon/radeon_display.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c > index df1a7eb736517..840c4bf6307fd 100644 > --- a/drivers/gpu/drm/radeon/radeon_display.c > +++ b/drivers/gpu/drm/radeon/radeon_display.c > @@ -933,7 +933,7 @@ static void avivo_get_fb_ref_div(unsigned nom, unsigned den, unsigned post_div, > > /* get matching reference and feedback divider */ > *ref_div = min(max(den/post_div, 1u), ref_div_max); > - *fb_div = DIV_ROUND_CLOSEST(nom * *ref_div * post_div, den); > + *fb_div = max(nom * *ref_div * post_div / den, 1u); > > /* limit fb divider to its maximum */ > if (*fb_div > fb_div_max) {