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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?bVLg0UuR463XLZCrT1qh5YFsRQTEyflavrCmGFyydhCVy+w9DkJ/ltbSsppR?= =?us-ascii?Q?i8/nLfVyancSERD5qtV5MPvirtlyBvd/fcw634IH8KGCB2FXKBPtfr/xY+XE?= =?us-ascii?Q?TDftacnAIexs3DIZTkETMMa0GDLYw2546YO/0/9BTsOuAE5/7ppXiMHE4BEk?= =?us-ascii?Q?NxADnf4afdIk2t0V+EmGj+wdYoRMz3Pc6ZNMDEh83QhENRZ3BGCpxmLAPuZx?= =?us-ascii?Q?qgd/As8AFErT2ZjFg5rMmmAmt5va6HVt0nE+VBcaxsa34TcM6+QX1ErHlRQk?= =?us-ascii?Q?+66ZxmkfNf0Cp5m7KvlDardOeLfTlQjuzt6c9spU7WQ2xdEKR256wEn342Gg?= =?us-ascii?Q?GwlXVhUEw8eDnV36NbDxrQvgxp9IDGIN2mhqRvjXHa5SvC8jIQd7oBEdoAjW?= =?us-ascii?Q?QW+018kaYrk72BQLhcFOsbKFCkM4S25ZXBzfVSMwc6zwuNgohR0C8usn8jo6?= =?us-ascii?Q?GCXjEIfR94kMDQSLfcDh6psCcUqF5aULicgv1ahsnM967okxUI09+Pqr3Y/F?= =?us-ascii?Q?rHNn2xkGVtWErjQZ/32k1pRouUSOB/wBeijz2kpHA3bnqTYCo1ElJG++0tfV?= =?us-ascii?Q?Jl2mJd4NrnGVuVQH/EuEumSLU5nCZfN4GJ+m3HAR6qZamsicxDdlWPgYpDoV?= =?us-ascii?Q?Jd6QJnTUfDY8YtG9VnDo7kvsXKh8c4uVHf769YxXmuM4ZT+liO9QKWyeWIDy?= =?us-ascii?Q?OtvOf07X8BRtUu/pg3+3HIpSuwXQQ6WXfAIbFgZlZoMcC/csA2pQhnAPHDFW?= =?us-ascii?Q?493mXFYktvkiycLWrRXoK75qPcPspmX6KNESpE4xe2iKZejFyv7NkeIrx93I?= =?us-ascii?Q?Rgk8n/g1VQF+7HRLogAxeAD4ZkSlor4mmOT9NjesM1zjjEArimxOOgYcfe95?= =?us-ascii?Q?9sEE2yTFqS6AlCeAmiztu16jPgnn6v2fEfsAplHlzeaycQ1xbTdJotm4QHzs?= =?us-ascii?Q?/BUHLj8y4Tka84AiyyoiHyhRvbtqs6Jmn9vdGATw8OxzciKAgAyRW/MX5/6t?= =?us-ascii?Q?mexEnGvP5ZZTltCU8M2xP8RYurvqDJQjOeyMr8te6Gm9PRDsi/btpQuEI2gT?= =?us-ascii?Q?3VJGpHrjHsiOT2u2lSdcwnhGI3hdy6g6B8r8nsHxQnGxmvwg1NNN8HsmzQCY?= =?us-ascii?Q?xBv5Ny+V3K5egoAc+DT8gDDP1DXQ0dP8cpo3RWI1EbbfxK+bcwjldicNlhtI?= =?us-ascii?Q?v5+4hMoIPW0H1qlqi0bXooqGfX9c+Jx5tQGHKjaanm5HLgDWKljJx0k+yC+y?= =?us-ascii?Q?IU/m82lXpoDvAlOxTlTeCvdmpqkLUmwZZlWUQuciqpmqHyx9cG8iKnLXWa6c?= =?us-ascii?Q?GQ1dS7g9TJAjHYPOJwLoSe63RAwqC8Mrg3b/u4oswM5aYxea2gnZEsd53Dzq?= =?us-ascii?Q?zZb8PMZ5+Ptvlwp50BmDBUIcTMyHpdOI7bMJasZff2407h82V4dVdrXUVcZN?= =?us-ascii?Q?F57evSI0rEazi+F1UlBDP0NspIaH7385frNUza/sQ3LDojx6uCHnp1HdLCuT?= =?us-ascii?Q?8RfoxwYRkD3fvrBjyjkedjoKxhfyVFKvieQ5pgB1M0gMpTM7uWCQCRnL1o4V?= =?us-ascii?Q?9CWr+i3QgSlSbK8lWNSVxbniFcApaaopXMY368Dji34aRTkGIYHXFHdcBAAu?= =?us-ascii?Q?VD+EYqTWdDKLkX7WHdWOPDUc4d3ZchBA4P7tGrkSNzLsef1lHuhSSfcjyJj7?= =?us-ascii?Q?LJ1HKFiCTc4kpB2YQ3KX/l/Hl1167pmILrTe35jjCxVAf5gUnjTu+h9svDbN?= =?us-ascii?Q?DinEPP5mWg=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 691a0759-b9da-4b72-b047-08de579639ea X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Jan 2026 20:06:26.3014 (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: 8wCKbX09FcSPxBJnKjmEiTQVtk5WkZngZ//ViL5Pnzjd1l7U6zSzwnbMrdjz4Dh+ X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB7174 On Fri, Jan 16, 2026 at 08:56:42PM -0800, Nicolin Chen wrote: > +static int arm_smmu_master_prepare_ats(struct arm_smmu_master *master) > +{ > + bool s1p = master->smmu->features & ARM_SMMU_FEAT_TRANS_S1; > + unsigned int stu = __ffs(master->smmu->pgsize_bitmap); > + struct pci_dev *pdev = to_pci_dev(master->dev); > + int ret; > + > + if (!arm_smmu_ats_supported(master)) > + return 0; > + > + if (!pci_ats_always_on(pdev)) > + goto out_prepare; > + > + /* > + * S1DSS is required for ATS to be always on for identity domain cases. > + * However, the S1DSS field is ignored if !IDR0_S1P or !IDR1_SSIDSIZE. > + */ > + if (!s1p || !master->smmu->ssid_bits) { > + dev_info_once(master->dev, > + "SMMU doesn't support ATS to be always on\n"); > + goto out_prepare; > + } It looks right, IDK if Will would prefer a formal ARM_SMMU_FEAT_S1DSS though. Jason