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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jonathan Cameron , Huisong Li References: <20250904040544.598469-1-admiyo@os.amperecomputing.com> <20250904040544.598469-2-admiyo@os.amperecomputing.com> <20250904-spiffy-earthworm-of-aptitude-c13fc8@sudeepholla> Content-Language: en-US From: Adam Young In-Reply-To: <20250904-spiffy-earthworm-of-aptitude-c13fc8@sudeepholla> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: SJ0PR03CA0211.namprd03.prod.outlook.com (2603:10b6:a03:39f::6) To BN3PR01MB9212.prod.exchangelabs.com (2603:10b6:408:2cb::8) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BN3PR01MB9212:EE_|DS4PR01MB9250:EE_ X-MS-Office365-Filtering-Correlation-Id: f563f7a0-4dfe-453c-50ff-08ddebd3b143 X-MS-Exchange-AtpMessageProperties: SA X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|10070799003|366016|7416014|376014; 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Messages are sent on a type 3 and >> received on a type 4 channel. Communication with >> other devices use the PCC based doorbell mechanism; >> a shared memory segment with a corresponding >> interrupt and a memory register used to trigger >> remote interrupts. >> >> This driver takes advantage of PCC mailbox buffer >> management. The data section of the struct sk_buff >> that contains the outgoing packet is sent to the mailbox, >> already properly formatted as a PCC message. The driver >> is also responsible for allocating a struct sk_buff that >> is then passed to the mailbox and used to record the >> data in the shared buffer. It maintains a list of both >> outging and incoming sk_buffs to match the data buffers >> >> If the mailbox ring buffer is full, the driver stops the >> incoming packet queues until a message has been sent, >> freeing space in the ring buffer. >> >> When the Type 3 channel outbox receives a txdone response >> interrupt, it consumes the outgoing sk_buff, allowing >> it to be freed. >> > Sorry for not reviewing your mailbox changes in time, but I have > comments/concerns on the changes merged. I will respond on the original > thread with questions if I manage to find it, but it doesn't look good > at all to me. So I would want these changes to be on hold(not to be > merged at all). Yeah, I was a little concerned those got merged without your input.  I will look for the comments.