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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?BPSv8wPxOpln8htAzPvD7NwO6ThNL3BbjrOq8qdk2x8XMxRog8aBbKSb4OZh?= =?us-ascii?Q?lOxZSEQh3RLI/oMwv0kUXR5XX7lGMLgQLg587Ogwba18QaRerx+IijXojnZX?= =?us-ascii?Q?6WPcEYCCtEucjX1RBXpI4/ynYYxth5gPaiSziCAss5lye2W7F8LkzTLbybZI?= =?us-ascii?Q?mwd0O2QHayWac/KKjumcTqrZLV+XNq+W9jesA6KmPy+iW5Sse+i1OYxvVkY/?= =?us-ascii?Q?ChtF3RNsMOLITvgh7PhQ0zt/ggozzg63JlOMPoNiEi0n5hM9xsqtdMdgZO1J?= =?us-ascii?Q?CSMIRBIUdWcjAEmvAMzhzVz3e22Ddasl20x+Fr73MeX+cBhJi/3XVx0uw+Zg?= =?us-ascii?Q?aNpENt/nOLqgvOHyI6anczACAm2FPHH9ZvFm6sYVFpkT/onz9+ysY1NmXMNv?= =?us-ascii?Q?ynqJMkC/H5PYWzVrKpO97gvSBbaMh1vJZxeBrhhIMrE4Ws8To5i8jwqkHTBL?= =?us-ascii?Q?gcBBNXsMWH0xn0+y1XSH9SowbaKiWUcWISIo19saQAwXiBOr7Vqj4WmHjms5?= =?us-ascii?Q?+fpD76OOtKo3BANg+ML3jjaKnLKUfIctflRvwxtqvW378BAPHA8hgNt8Bs9J?= =?us-ascii?Q?BuWmOY2saZRSbl9QWYHW72YllQPabnAEJ7/fU8POJwtKFbimc8boDZeK/Dee?= =?us-ascii?Q?Y8Ov80jHaQfyVRcCnnWmgAUx0L51/PK0gSdDgw3EZp97nLZIaZoyTcA0/uCk?= =?us-ascii?Q?us1KAaCIGAUZ0RZjAosAHDrfy2UYlmlq8xomIRUt4+gtnNJyyv9FW7wATYEx?= =?us-ascii?Q?wJsWU9hldCDRHmb/lizoRkTsJDyLkiRz7Htvyoqjzu2dvaQsPt1qFWmkRlc7?= =?us-ascii?Q?qnrJABZ/2SLAJdZNrGMMcyXRaLP+JqYuV+c7HuaEce58t/qZAZ04kW8HkEvX?= =?us-ascii?Q?CLaFwAFqAFsTmVB2pD2r0bG6oUxpt2x/xgXHnnkhOojcoiYlzrsQk5I/9l1i?= =?us-ascii?Q?01JLDrsv8oNlIFWo9lSdQqDJ2+BwV9+/MkfbXfdzHPq/x24AYDWe+5nE8wjB?= =?us-ascii?Q?C6ZQrAWOVeEb7KpF4UX/vzWjm2PzYwJnyDOz4DwMSUTN9xFNFD4XY15Q5u5C?= =?us-ascii?Q?ZntPo/BvkxXYgmPd9N4Vcb+UZFbQQTX6GjYDWPpx6o9VRvwnWa4o+K3vYs2k?= =?us-ascii?Q?Hg1g2T9q8uMtS5OQnDNdkDRovuBmtS+2b69aBiezGO/hu7dhNS+qaceQTOLo?= =?us-ascii?Q?3OuKuc51w2TSumL6yGS8BhcwlICm0iGhNn9WDepE9dwoLpntK0+qkawMnuYw?= =?us-ascii?Q?dqprOM/E1CLXEK4sqNEviq+Jf0lBNYQE4ijXIfSlD9fpcSWHoq5D0SOkQNcW?= =?us-ascii?Q?JUD18PBApfmaARHTRln9ZIymp1pfNcvxAShbE74oswWJL+htM4/cR8FU+D+p?= =?us-ascii?Q?C1Rh9GtzgakyNrd01fQgDngv2Jn4WzVnYPPlHy5ZWGMbEZzpuNmJCkNUXPhc?= =?us-ascii?Q?B8G+34sfMkTlQEgr+Nutqahco7DRBpM8a5cRuhsG0lWE7p0kv+NO1BQCSvwI?= =?us-ascii?Q?fBCR/01TmmwwHNqpAsDj20mDT69IgpiB90I1wq4twaAui3mMO4GM/6B8Ok2B?= =?us-ascii?Q?wJcNQvGAtO9ablJ0c8c=3D?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: fdf102db-31f4-44f8-b110-08db8f7bc6a0 X-MS-Exchange-CrossTenant-AuthSource: AM6PR04MB4838.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Jul 2023 15:03:18.1245 (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: zc/xSbtxtBYCwlEYnelunGsrEqPrzq+5CiBOwPJKV4Gy3hE/FReq+5+tjexNTKm5q6DNmA8r05IB4H6hH595BA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB9PR04MB8091 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Fri, Jul 28, 2023 at 11:05:56AM +0200, Lorenzo Pieralisi wrote: > On Mon, Jul 24, 2023 at 05:58:29PM -0400, Frank Li wrote: > > Introduced helper function dw_pcie_get_ltssm to retrieve SMLH_LTSS_STATE. > > Added API pme_turn_off and exit_from_l2 for managing L2/L3 state transitions. > > Commit logs should not use the past tense but the present tense. > > eg s/Introduced/Introduce > > Furthermore, read this post from Bjorn and follow it to the letter > please: > > https://lore.kernel.org/linux-pci/20171026223701.GA25649@bhelgaas-glaptop.roam.corp.google.com > > > > > Typical L2 entry workflow: > > > > 1. Transmit PME turn off signal to PCI devices and wait for PME_To_Ack. > > 2. Await link entering L2_IDLE state. > > 3. Transition Root complex to D3 state. > > > > Typical L2 exit workflow: > > > > 1. Transition Root complex to D0 state. > > 2. Issue exit from L2 command. > > 3. Reinitialize PCI host. > > 4. Wait for link to become active. > > This does not explain what the patch does and why it does it. > > Are you describing the L2 entry/exit as implemented in the code ? Yes. How about below commit message: Introduce helper function dw_pcie_get_ltssm to retrieve SMLH_LTSS_STATE. Add callback .pme_turn_off and .exit_from_l2 for platform specific PME handle. Add common dw_pcie_suspend(resume)_noirq() API to avoid duplicated code in dwc pci host controller platform driver. Typical L2 entry workflow/dw_pcie_suspend_noirq() 1. Transmit PME turn off signal to PCI devices and wait for PME_To_Ack. 2. Await link entering L2_IDLE state. 3. Transition Root complex to D3 state. Typical L2 exit workflow/dw_pcie_resume_noirq() 1. Transition Root complex to D0 state. 2. Issue exit from L2 command. 3. Reinitialize PCI host. 4. Wait for link to become active. Frank > > > > > Signed-off-by: Frank Li > > --- > > Change from v4 to v5: