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charset=UTF-8 Date: Wed, 18 Mar 2026 09:56:02 +0900 Message-Id: To: "Danilo Krummrich" Cc: "John Hubbard" , "Joel Fernandes" , "Timur Tabi" , "Alistair Popple" , "Eliot Courtney" , "Shashank Sharma" , "Zhi Wang" , "David Airlie" , "Simona Vetter" , "Bjorn Helgaas" , "Miguel Ojeda" , "Alex Gaynor" , "Boqun Feng" , "Gary Guo" , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , "Benno Lossin" , "Andreas Hindborg" , "Alice Ryhl" , "Trevor Gross" , , "LKML" Subject: Re: [PATCH v7 18/31] gpu: nova-core: add MCTP/NVDM protocol types for firmware communication From: "Alexandre Courbot" References: <20260317225355.549853-1-jhubbard@nvidia.com> <20260317225355.549853-19-jhubbard@nvidia.com> In-Reply-To: X-ClientProxiedBy: TYCPR01CA0160.jpnprd01.prod.outlook.com (2603:1096:400:2b1::13) To MN2PR12MB3997.namprd12.prod.outlook.com (2603:10b6:208:161::11) Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH2PR12MB3990:EE_|CYYPR12MB8752:EE_ X-MS-Office365-Filtering-Correlation-Id: a03b6ae8-f4ef-47f4-9497-08de8489222d X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|10070799003|1800799024|376014|7416014|18002099003|56012099003|22082099003; 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>>> + 30:30 eom as bool, "End-of-message bit."; >>> + 29:28 seq as u8, "Packet sequence number."; >>> + 23:16 seid as u8, "Source endpoint ID."; >> >> hmmm, I seem to remember my very slightly younger self insisting >> that fields be listed from lowest to highest bits. And now I've >> violated that in both headers in this patch. arghh > > My now slightly older self still thinks that what you have above is actua= lly the > way to go. So, I think your current self intuitively did the right thing.= :P > > It should be either > > 31:16 > 15:0 > > or it should be > > 0:15 > 16:31 > > with a strong preference for the former, but this > > 15:0 > 31:16 > > still looks pretty odd to me. Mmm, that's the order `regs.rs` currently uses. I don't have any particular problem with it tbh. The second form (`0:15`) is going to be rejected by the macro - it expects the high bit first.