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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?em5YXvzUrpJ4N3ym/yxJfLdFZuNbN6K/uQg7Cy1pjzseo1KFaz5kH9YKJakd?= =?us-ascii?Q?mVhO02lLym/76yiwEQSK5QQq3YS8FgtV4U6YHV7gHyPNAnvRO7X/Hs82rfPx?= =?us-ascii?Q?fxusCDXv2kvxl5WWfjT8l52TKOLCa9mz0wp82x6HPujhoSkeXceNlEkpyG13?= =?us-ascii?Q?CZgA8nIcH/M2GUValuuvwvPCG3R6h8CVKSLSyBYxmvIqbPgr1Rsrp91jxLqb?= =?us-ascii?Q?QzU/aGNG41837ItftfKMpLxB/Vucah6+bcL6fhpyvv2Z+po9zbozdSfbBLYD?= =?us-ascii?Q?nJ+kwOcy4iekmMGRZPc5syeqC6AAKadvU7Mza0qoaz0ogCHQ7vLOT/CalLeV?= =?us-ascii?Q?rwlLkbHb8yMGfl9lcxqBA+0Ff3sbhFYc5MGQMWvgfMZzXBoEUCpuufQ9xdqR?= =?us-ascii?Q?U1E/ilETKv1CDGW1L059C00n/JQMYpiFWhMPEnb6ifGvCZRgHY0YNi1ZHLO5?= =?us-ascii?Q?vMH3HBoXPudG9qO1kFOdpJbE6jsmlcXh5EB4EeCGRiLzIi4lZTx1CySPsBSK?= =?us-ascii?Q?QbWQXbphsiWJ0cWL+0J2F79R+gpICw8YN2/su4jbS6tqMNWxQnaot7zDqBJd?= =?us-ascii?Q?gRUA0Bn6DONU8tcGLn/i4sugkQN4JxNkMrdRLpVaut5fw+Q/Zd+n7CE6a24j?= =?us-ascii?Q?BgQ7GgDnNAx99sihQXBTkuIgu6E274kwY1VfrFQNWrd3gqBOrPq9Egc52iTs?= =?us-ascii?Q?Et6WJuCvdQtjleMqwlT02Kf5SdoXjUG3bxiorXvGEoi8wEAgtcziJVOdt0+J?= =?us-ascii?Q?PdkFIa3aBECeH8ajvHide6ykQY55x3aogBObteP6KU3X3OTD6gmzcGjP/5iq?= =?us-ascii?Q?/H51RJxudDVqskQIQLy1bSlZ3ZOrsxDfSkl7DLol8F2yFguwqfQ5mtFqE+NZ?= =?us-ascii?Q?VpFHD3l5aqZqACQAIWq9zYCSN7paVOuPTlTB/Takfx8/l4G1K7A7oofL2EaY?= =?us-ascii?Q?UPl2jA9eabAhYkytjNu5kVBE53ht2DUWl0JY0wOHeMPrMcQ8F5qVR+V8O5lg?= =?us-ascii?Q?Z3xyLVMIR0Y9fXFoe04VgR0kXoVR6sbgZ+eJL7zKVzXTZZXDfaOOnzKg60up?= =?us-ascii?Q?CzOkIMCTNTE+LWtjlI9UvL68AK/kYUhApD3R57Oj3416pWzyxeLBdLgO9E9F?= =?us-ascii?Q?zHBLzz/xDM8KViYpLYyB7T2pBMPJ2Ry/LfTabf/9zuQcPEhsoucfRs2YTgfn?= =?us-ascii?Q?IutNMJ3SgO8DDN9RuM+vzR31zeQuLe6DDI+q1mdj+SdoXU6XbDOFuGscdJfu?= =?us-ascii?Q?APMbnXioODxhwKMwqAZAiPZzFw+4I4TsOYN7MAyION7zk8iaZ3xJ4IPupIWe?= =?us-ascii?Q?LZDIqNA+I8jz7k3bLxgCukBbzHhMLqYqx4BEFSooO5hupzN/1nR/N/ijas7F?= =?us-ascii?Q?HiARX2Tobuywy2JvPbTGbEcGuZ9MunQOvdzW06hAljl9czVGDD0+52L6iOhw?= =?us-ascii?Q?5IoBnuKGLtqkql5GG4rQ6goy+E663Ig9YaDmZxHDPI5RYcf6LXwPsvYqiUPq?= =?us-ascii?Q?pwHLb/j5sgF6R0iz1BbR4Fzk7Gh4MaQOHUrB6XQUpEQqgcCOMz8a6CMg2f6r?= =?us-ascii?Q?ngO4Sd3HVFvSjefa4K6QveH/3UXNJLEu+3B0KJTk?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: f2296d3d-29f0-4a9b-28f9-08de341b4d86 X-MS-Exchange-CrossTenant-AuthSource: DU2PR04MB8951.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 Dec 2025 16:28:20.4457 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: ooCxMYMGDEayWTugy+S+xbW3P7Wj8P41rSLpZfM2B3VffUduQet3EQjjHSsCxIvTokYr1UfQ4pYIorWsxJHJ0w== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI0PR04MB10231 On Wed, Dec 03, 2025 at 11:39:21AM +0100, Niklas Cassel wrote: > On Wed, Dec 03, 2025 at 05:40:45PM +0900, Koichiro Den wrote: > > > > > > If we want to improve the dw-edma driver, so that an EPF driver can have > > > multiple outstanding transfers, I think the best way forward would be to create > > > a new _prep_slave_memcpy() or similar, that does take a direction, and thus > > > does not require dmaengine_slave_config() to be called before every > > > _prep_slave_memcpy() call. > > > > Would dmaengine_prep_slave_single_config(), which Frank tolds us in this > > thread, be sufficient? > > I think that Frank is suggesting a new dmaengine API, > dmaengine_prep_slave_single_config(), which is like > dmaengine_prep_slave_single(), but also takes a struct dma_slave_config * > as a parameter. > > > I really like the idea. > I think it would allow us to remove the mutex in nvmet_pci_epf_dma_transfer(): > https://github.com/torvalds/linux/blob/v6.18/drivers/nvme/target/pci-epf.c#L389-L429 I check code drivers/dma/dw-edma/dw-edma-core.c does device_prep_interleaved_dma() work? which have not use config. Frank > > Frank you wrote: "Thanks, we also consider ..." > Does that mean that you have any plans to work on this? > I would definitely be interested. > > > Kind regards, > Niklas