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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Wu3OwkS0OIgugBFAf8UZBZSt7Xx65b4wHJAxV+pqF1vdqW/vVHIHY0sUkFAW?= =?us-ascii?Q?coqkANOpCDvBz8cQ9NEuAOnhutkbv+/QSRKyfLngZvoYDH57n+KWTPFRzw4N?= =?us-ascii?Q?kePQbjXEeMf+NNaX7IuJm2+xeXz4hW4pjbzN3dq6sfUqBJAIwhRsYUnLTL0F?= =?us-ascii?Q?ydT/RA3eWzxHJiEjE0QCZ1SJwon/oUzHRy2MjhMYQBfJVyyPjs52B4fYVq6f?= =?us-ascii?Q?fIHiAlzPtsbZ+49AhzwH5wqS3kKYChdTQ8UJjTT71MAHcWvpz+MkVcA6mCE1?= =?us-ascii?Q?djDVGCtkWacIA+P7JTOUZMz1Wqdo381AbjJ+UxADE6FHTOreZl5EpWH/wcA/?= =?us-ascii?Q?ZWPQ82E/BoMI6H1/+ohVkFj7oxkcTWPZcqFlQjng9AuEsv50UgDTKWkTImNE?= =?us-ascii?Q?IxudfG5+VDKISP7SNlEwRo2g9vPHlLX//vBwmUxeQpYWugEN6XU7K/4i9hCZ?= =?us-ascii?Q?O+4bFAWUf+TLj926kIeLBSunYmb4IG+m+U29SE+rP6m6li1PACd10CoYKQGe?= =?us-ascii?Q?gYq92c65qny8Yg0MXUq4c581LlgiQqC4mdaJ6/08f7rGP3xwpCUM7ndpDeEk?= =?us-ascii?Q?/ADZPd4+KB90Zoy3EX4jCnQlASHbKXljg816GqAqK61whLUVho/HvdhEDj6M?= =?us-ascii?Q?/lfQUFCAHM2qVR7SbQKU6QdwYw6Cw/G6zL0jMPWWji/EoRoF3oVQa/ybaknZ?= =?us-ascii?Q?w6vMvK3sm/Do/sbTMzsrGl5YRS8H7ed/FypDam/2K4PUMzJV78+NJGR3t+dL?= =?us-ascii?Q?RTu59yZQssr/UMFg6Z9SoOCHuSeBIv43BApeGEszERIlgyL2dy70cKdpkv4j?= =?us-ascii?Q?FAvDUeV2ktfos20GaNMo1L60TXR+GNL7kqay+nIwr6rw9wVGEiKymQSUKrdP?= =?us-ascii?Q?KM+KKl9VN/FLWEGtn/7WV1bC8OPQc/vT4su2+9RWylBONIRPiZEo4D2o3f98?= =?us-ascii?Q?MW8jdbFi+gqgSjuUDVINqHA4EHEedOEKH6aSDqvzaTv4ijZbnrzGTATfoR4A?= =?us-ascii?Q?+WFtwVI5ELHqEfXoH2zDbwczUyDjME2OrcX4Iwih+OJuJOe+Bdk8sfjU/GXv?= =?us-ascii?Q?cp31g6icd/qJZVWrPYkqV1DW4xPlVPHIfQqXFdKBa7vskMOeyXMEgCPKbM4g?= =?us-ascii?Q?urwmOgR259sBlLfMvaeHKm0s6TTv/YCpwecQ87fO6QvdQd2oxLaiy5h/rzmO?= =?us-ascii?Q?BSWGGz1yosp+gbhsBbV1JxU6+AELnrD5q7hG77LvNXjBsN5g/dQe1gK4ysqh?= =?us-ascii?Q?KyejcIQjtd224Im5PwdqwKoLMadhw4ZR36bHTpbAlT5U4iuLhOntBRCQMBPN?= =?us-ascii?Q?2sPKjQcK6Bf1xhCI1DDScSnAn9t6wHgB3UT95uJGBvlCiFivKSTwGN0t6PQx?= =?us-ascii?Q?QzSmf9lRrAJ5IPXngbVV1IqLA+1qknSNWv0u4j9Z79eHz25hIAxxUV+JziNo?= =?us-ascii?Q?aQ/gJFBUUH0T7sdcjusn0TfpIiq6Uv4mgeHgEGMKKs6FVVRjztMYrHPDpgXI?= =?us-ascii?Q?j3YyWzv/DKXNLJoQf1ErAr/nakTYXS649AHJGqUqy6UhjKfs9FInzpzpNp25?= =?us-ascii?Q?/okf1uNrFAQnSnDVBqOGVeHd1voqNuD0ylvJuwVq?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: d5c355c5-ff58-4f0f-cb6a-08dc32ff7cb7 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Feb 2024 17:06:47.1390 (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: m1HQan61wMfbZ++t3tcBVGwH6a+tXhYmNe0rBrW1ZiNs0Ic3PKHlrG1iHB//j+sz X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB8829 On Thu, Feb 22, 2024 at 12:19:06AM +0800, Michael Shavit wrote: > I think the simplification here is in the first if branch of > arm_smmu_write_ste. With Will's proposal, we only perform a hitless > update if there's a single used qword that needs updating. The normal cases like BYPASS -> S1 still require updating QW[1,2] before updating QW[0], and the reverse as well. That still needs the three entry_set()'s to process the same way. >From what I can see if we did 1 bit per qw: - get_used becomes harder to explain but shorter (we ignore the used qw 1 for bypass/abort) - arm_smmu_entry_qword_diff becomes a bit simpler, less bitwise logic, no unused_update - arm_smmu_write_entry() has the same logic but unused_update is replaced by target - We have to hack something to make SHCFG=1 - change the make functions or have arm_smmu_write_ste() force SHCFG=1 - We have to write a seperate programming logic for CD - always do V=0/1 for normal updates, and a special EPD0 flow. All doable, but I don't see the benefit in aggregate.. Jason