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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?pcn9XZJ12E4nZoDiaI2EmDwM5TtQvlxIkHxMYjld53QvGQRU+kgUkfL4nRhT?= =?us-ascii?Q?CVIBIpvRe1xA5EQeRKBHgAyAzJxP1PtswgQrNxKZC+ZApih3c4P9g2eb92kz?= =?us-ascii?Q?6v3zlVta11qOQmAI3h6Ib12traMvNxQ/sOXixQmk5hJ2UJPe+0h05EPrPxKq?= =?us-ascii?Q?boRfpy25MENF3JvWc9SA0Sc1SX3lDRBpdOrGowo9tMjbo20H2F4hyeQmbFIR?= =?us-ascii?Q?AF3zCNACOnwPfO6RhE+X9dILlOYxypOtVJ0JZKUQctcZir1HMEwfA8mKtEco?= =?us-ascii?Q?gcGTt2s+EzwJ2Uvlb66EJFIrDczTUUdDsSA55OFs/PZeqw+QqeFASkRoEAmb?= =?us-ascii?Q?5Omgog8PamEWJj+IBqv7GiJ2frZC6OmoFE6TIDibiUmIfv/e1+dZtZEYQRUf?= =?us-ascii?Q?e+2d/xYhJUxx4L5KpFoBGrxJbeb5kvHdq1a65ZFpp2/YZnydGzVD6PGJoKii?= =?us-ascii?Q?5UrIpEodZyVIuAw0hJeyw23CHm4vPni44fyUU0LDkkjirOYYthfRo+tDNgcn?= =?us-ascii?Q?nM3hmJnJhKK6xXyJCDsvqf/tuQXU0juaBVhF3+EZMIy+pkViANH+SjXNNx4b?= =?us-ascii?Q?YQSsnRCiVYT+gyIrqJxQlinp4iZOabrCA6aeOgRG959dF7OpyQB00MgXEAVq?= =?us-ascii?Q?BRm67I7LSXcvO+KeF4jtVETjlkWhdntJTsBiSHTj9MVUghwiV9m4jIpW6Amu?= =?us-ascii?Q?CifCsQu1aIzEpRwMBoZQTyDtegeCnMI/1XMhoRT+1kCciijA2FSnQwfx0/vU?= =?us-ascii?Q?oKu1VA5Itaj2/0v45FI50+Q4Pu10nN69fx2BRqecuonVN/H5wjsYnbseqVai?= =?us-ascii?Q?wBX13wq8wdTzkobq74nvZ7StPIPw4K8yEqYLQb5tlFdcYcR6CBasWNewMulh?= =?us-ascii?Q?KNlDjCV2BGs8FXmASH7Kfoluib1pksG15N0pjSdL2peb5Q1TFhgg86cV1+mp?= =?us-ascii?Q?SSegnUkeMeZ5jLLYRASxbShKAIz/V7UF7jOf2p541d5+mOxXUvKByUnS2YbI?= =?us-ascii?Q?qoD5YB1jbX6+NAOb5Lg7Gzf6UO1zaukSKwT1wWhu3ODH9aAo3GBck1a/EjXG?= =?us-ascii?Q?4iwixGXuPXHGmNDMXAENUIbaamYI8x1MwbNDwusUYbde8Yg8Wu7iLfJETPnf?= =?us-ascii?Q?38e+pB8iB4bKtLSzFne9VWxXx8G16tiL9ueH6evIBio0BS+T7wEQFAnlGoxn?= =?us-ascii?Q?clLT6TVw0/zlOjW5wsxfa53GZNcxKFpSBYPqEBxQx1KR+CA9bhsOzc5owhib?= =?us-ascii?Q?bhSLB8vnM0FChtzzQuw7pVQ1JDYZ4RycZbQgpHnxjtAK/el/37WoiEN99+OE?= =?us-ascii?Q?DkppPy4lI1fn+K4R2KCD+SeBelJ5d1/C3Qs3ZkksyaAYZwAev2LmDvaga/q1?= =?us-ascii?Q?pCthQQZtgqdk225y2BwScZUgk1F6/DYOR1Y0Fd7s0UZXOLArEriX658pa87Y?= =?us-ascii?Q?lPMiwPiudBVyXRFOvYgBTKl7iJ094KpFpun0nGnS4I48WXmsa7M+ik/pPgM9?= =?us-ascii?Q?8jXMkBYFGuqzutc6qbPneeQMk1eCfXSpxpOEdU8DbDGPUhdFxIQrH0Xnvlw+?= =?us-ascii?Q?RyP23c/K0CQ0xsWyQbE=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 87f23bdb-85b3-47c1-1cfb-08dcad74691c X-MS-Exchange-CrossTenant-AuthSource: DM6PR12MB3849.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 26 Jul 2024 13:11:07.2884 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: OsRGfsr91lMbDFM1SoQQuVuyCyA0XJ6XEu53/nfJEv29p6Tcdai/bj8L440LdKWX X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB7039 On Fri, Jul 26, 2024 at 03:49:49PM +0300, Laurent Pinchart wrote: > What is not an option exactly in my description above ? We have multiple > V4L2 drivers for ISPs. They receive ISP parameters from userspace > through a data buffer. It's not allowed to be opaque, but it doesn't > prevent vendor closed-source userspace implementations with additional > *camera* features, as long as the *hardware* features are available to > everybody. How far do you take opaque? In mlx5 we pass command buffers from user to kernel to HW and the kernel does only a little checking. There is a 12kloc file describing the layout of alot of commands: include/linux/mlx5/mlx5_ifc.h There is an open PDF describing in detail some subset of this: https://network.nvidia.com/files/doc-2020/ethernet-adapters-programming-manual.pdf There are in-kernel implementations driving most of those commands. Other commands are only issued by userspace, and we have open source DPDK, rdma-core and UCX implementations driving them. ie, this is really quite good as far as a device providing open source solutions goes. However, no doubt there is more FW capability and commands than even this vast amount documents - so lets guess that propritary code is using this interface with unknown commands too. >From a camera perspective would you be OK with that? Let's guess that 90% of use cases are covered with fully open code. Do we also need to forcefully close the door to an imagined 10% of proprietary cases just to be sure open always wins? Does closing the door have to come at the cost of a technically clean solution? Doing validation in the kernel to enforce an ideological position would severely degrade mlx5, and would probably never really be robust. Jason