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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?6H/eQT4kL+2fBg4Cvq8dL+VYIKnCT4l8C64PN3Ns+FvRS1VC05XD8Lwvf6Uo?= =?us-ascii?Q?Y4c2RiAHbLxlMf2l6FoRUay1poCxhDTPXBH8ZuY+G2pmf+2b95TmHeZWKyEd?= =?us-ascii?Q?w5mj4kEvsNiLKqtueT6/SjYaxCsd0eu3fK09Xo+BgCiQGgFUg7TR6+trHkaf?= =?us-ascii?Q?4RmmyBUG1/xhq+93iIsy5isCaQgjGRx4n1V9/O9vy468RnT8kPizcMDTlNTn?= =?us-ascii?Q?MkvrbkQLv77TCRRLX1L3UG4rxNnMVG/0A/dvB+3dQ5EaJ8P+o08HPKT0+AP2?= =?us-ascii?Q?7PL16lKAH5JNr/rP4ARAZkLRoXcSW1EzszBXa8LTXW0fKBinqCxKmnsoPNt0?= =?us-ascii?Q?TsTh3mn9i0uY+lVLBwS2QLzGTwgK/EcANJeKYNEpzqOtrAgezjFRvo0ByItK?= =?us-ascii?Q?3onUr6c5Aq2cX12mPGfY9l5D79AM75qI8YfqB5hBnjjiEW/SKyaQFgUvR2hk?= =?us-ascii?Q?lTi3J+4fgCZ136+r/0haLqeLPfjjKGdpUu81eGR+Wq29cevuwEL/g1Emz5Jj?= =?us-ascii?Q?sctk+hP555E5i1+33JXWcT6miZRq2zz6VUACS7xm0uSpKSlGFtQg6eKDZ5qo?= =?us-ascii?Q?Zd9iStBvKRy7c1LsCU5O5MYxHBQGn8Fi6MxXGqGcR1RiJ1HFNmrHKkTyoH+U?= =?us-ascii?Q?QVxs1ALnP6HG5+aYDSvssWSW1b1Xnuj2rnt2QnhJvKplA9RKpkecI3CtN0aM?= =?us-ascii?Q?UuYtNpUFutspDs615zwXJ7zh5bO9n/QI6EXgXMK3ZTeEWvRU4Vf/ZY3/WyWm?= =?us-ascii?Q?mIVTw/jRpDp/lFjuFKaTIlvjSTlEOAtNiefjpTRxIXy0qWuS4pC16vwOK98p?= =?us-ascii?Q?bmIOmivBzad5QDme4e0WK7jtZ+YQi9hk430Te27IuQBYfhdBZJ8k7xPySo/s?= =?us-ascii?Q?3EjH/O0SWohCQbJn6q6fvb1uEERNfvVafIOI2cgLMBhhj6ePHS+1H/oVJWaj?= =?us-ascii?Q?oy5JosP36j8dFT9x7JjJIF1nRmqoJz/K+vj++26PFUD3aMmAk2fRy8ywvBiY?= =?us-ascii?Q?C+cPxDXTvOhcLBGPXQrPHnPw38Ee/fMOoWH7coeHx6m7ZK1lHfJLmxT798ei?= =?us-ascii?Q?DWjB5K/zLDGF9FeCfdonGStPK5Z5IYbXTMLVHGJ3SWCUX4Ei/A+8jBjxcme7?= =?us-ascii?Q?NdeBIbiqw0T1GWkGSWE2uM9CxU3SMPMtH6t/K+8otcKfLnS1xl9LV2YCWAHW?= =?us-ascii?Q?K2w1/oaDsZJ2RoLurBuY5xbBc12pL+pLAW0VowCSu+wwut050kL92HU5B7RT?= =?us-ascii?Q?gey7RZmGaom8XtRdfvKjaGFyydXhVfp5kl1rhiDdE1LF8MUEFUOZZ+q8juqc?= =?us-ascii?Q?vCB3RcO+feeP7mgutzH5ey95GCIP60S/jongwPtDcTV5WxvXT0yADqDR9B5t?= =?us-ascii?Q?lFtknnrByWK7ZvAtwOcwY83gRniCK3Mt3TH8RfP2bXUTEczXOBAEHb35oYx2?= =?us-ascii?Q?japgLBlQjZdOg8yp4moQsO+jKFInZsqvYlBp/HEib7ufsRxPG87O0sjkiAaX?= =?us-ascii?Q?HDM9x9q1k8gQ8dyZBVnig7OnbAk1F7YBXU9+Myf+8o3RcHYK4CmBFVnZmiuU?= =?us-ascii?Q?kWFWSMM5UMIrmNkkbWfbEYmGOMD36HdwRRPCKSWC?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: 075bf470-b960-46f6-f646-08de2704f19e X-MS-Exchange-CrossTenant-AuthSource: DB9PR04MB9626.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Nov 2025 00:45:32.1873 (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: Sr2tbWXai7pflyzmv84WvcwL3ttlymCzXccXN7yFj6tm8kByKpdkHcwlU1GjvIsda8riMTOBLd8xm26PCtZU8Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AMDPR04MB11620 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251118_164538_384497_8A465705 X-CRM114-Status: GOOD ( 20.21 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Nov 18, 2025 at 11:45:46PM +0100, Niklas Cassel wrote: > Hello Frank, > > On Tue, Nov 18, 2025 at 05:20:36PM -0500, Frank Li wrote: > > > > > > + dw_pcie_hide_unsupported_l1ss(pci); > > > + > > > > Need call dw_pcie_dbi_ro_wr_en(pci) to access PCI_L1SS_CAP. > > I disagree. > > At least when checking two different versions of the databook > (one very old and one more recent), the register fields that we > are touching are all marked as: > > Dbi: R/W (sticky) > Yes, you are right. Sorry for noise. Frank > > There are some other register fields in PCI_L1SS_CAP, e.g. > NEXT_OFFSET, CAP_VERSION, and EXTENDED_CAP_ID that are marked as: > > Dbi: if (DBI_RO_WR_EN == 1) then R/W(sticky) else R(sticky) > Note: This register field is sticky. > > > But since we are not touching any of those register fields, > the current code should be good as is. > > > Perhaps your version of the databook says differently than the > two versions I have, but considering that they seem to have > intentionally made these R/W without the need for DBI_RO_WR_EN, > I don't see a reason why they would want to change it even in > the absolute newest IP version. > > > Kind regards, > Niklas