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To: Gerd Hoffmann Cc: dri-devel@lists.freedesktop.org, David Airlie , "open list:DRM DRIVER FOR NVIDIA GEFORCE/QUADRO GPUS" , Sandy Huang , Thierry Reding , Oleksandr Andrushchenko , "open list:RADEON and AMDGPU DRM DRIVERS" , Jonathan Hunter , "open list:ARM/Rockchip SoC support" , Ben Skeggs , Russell King , "moderated list:DRM DRIVERS FOR XEN" , "open list:DRM DRIVER FOR MSM ADRENO GPU" , "moderated list:DRM DRIVERS FOR VIVANTE GPU IP" , "open list:DRM DRIVERS FOR NVIDIA TEGRA" , Sean Paul , "moderated list:ARM/Rockchip SoC support" , open list , Thomas Zimmermann , Alex Deucher , "open list:DRM DRIVER FOR MSM ADRENO GPU" References: <20200818074828.9509-1-kraxel@redhat.com> <20200818074828.9509-2-kraxel@redhat.com> <9c355d64-1a61-eb59-be80-d9fc863ddf22@amd.com> <20200818082703.7z6fcvoymiqow5kw@sirius.home.kraxel.org> From: =?UTF-8?Q?Christian_K=c3=b6nig?= Message-ID: <03c03129-db27-c6da-df8f-909141d2a3f7@amd.com> Date: Tue, 18 Aug 2020 10:31:19 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 In-Reply-To: <20200818082703.7z6fcvoymiqow5kw@sirius.home.kraxel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-ClientProxiedBy: AM0PR06CA0142.eurprd06.prod.outlook.com (2603:10a6:208:ab::47) 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 AM0PR06CA0142.eurprd06.prod.outlook.com (2603:10a6:208:ab::47) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3283.16 via Frontend Transport; Tue, 18 Aug 2020 08:31:24 +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: 733fd9ac-5bf9-4479-2d30-08d843511978 X-MS-TrafficTypeDiagnostic: MN2PR12MB4320: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:7691; X-MS-Exchange-SenderADCheck: 1 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: LQaNOJXCKf3kKYJ59Cb2Dm2gnNaHZ0LBy4rCZViA0eu9SEgygFr7lqNBtLsLOSB2tOQc1grI/3ZgVRa+tWc+PDiQUCDerWl9qSHzFTxytn+WNbCUGwTGqm8P/ALyEUDnA4MDRDV0c3RgynClLR/qp6Y1dMvndi6/nOgHcjlHHjid1aOEW7OgNKjJkZgpwjvrqJyNCuDZQ55Y8marTz+vsF3U9JflaYbxHJ+rWIM/8yDGW9bqsS85fFMZJCvgcRuHPI3NkAIsxptt8PLvhDUTcxLr85wElcEj8ZUIhheGqPs/7mqNqDCvT17D3zVQStWryRUnSOaZi6caSSDonxSpJVhQJrRB5Nm1W1Aoh5yqPKwPwnuCtxc/JYVLfMsLm10R 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)(376002)(346002)(396003)(366004)(136003)(39860400002)(8936002)(31686004)(5660300002)(316002)(66556008)(66476007)(6666004)(36756003)(8676002)(186003)(478600001)(2616005)(31696002)(16526019)(2906002)(6916009)(4326008)(86362001)(6486002)(66574015)(54906003)(7416002)(52116002)(66946007)(43740500002);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData: 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 X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 733fd9ac-5bf9-4479-2d30-08d843511978 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB3775.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Aug 2020 08:31:27.6280 (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: hjBcB47fGEt4/fIiRNL0Ry5fSoEAzS0fx60Ge7bc3/5IWqE2oGhkiPzhznoF/Lzd X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR12MB4320 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am 18.08.20 um 10:27 schrieb Gerd Hoffmann: > On Tue, Aug 18, 2020 at 09:57:59AM +0200, Christian König wrote: >> Am 18.08.20 um 09:48 schrieb Gerd Hoffmann: >>> Add max_segment argument to drm_prime_pages_to_sg(). When set pass it >>> through to the __sg_alloc_table_from_pages() call, otherwise use >>> SCATTERLIST_MAX_SEGMENT. >>> >>> Also add max_segment field to gem objects and pass it to >>> drm_prime_pages_to_sg() calls in drivers and helpers. >>> >>> Signed-off-by: Gerd Hoffmann >> I'm missing an explanation why this should be useful (it certainly is). > virtio-gpu needs this to work properly with SEV (see patch 2/2 of this > series). Yeah, that's the problem patch 2/2 never showed up here :) >> And the maximum segment size seems misplaced in the GEM object. This is >> usually a property of the device or even completely constant. > Placing it in drm_device instead would indeed work for virtio-gpu, so I > guess you are suggesting that instead? That is probably the best approach, yes. For Intel and AMD it could even be global/constant, but it certainly doesn't needs to be kept around for each buffer. Christian. > > take care, > Gerd >