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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?S4AfCzpXF3ow80d3VvTPAZ4aIcErcRgU1UFCk81yTWtyTLCEYt0NTEpSEI4g?= =?us-ascii?Q?FngUeVCtM5MJ7qZMGlcFAvWTkO7wK2FTzRH2/6uuyaF3y4bq17PYQazhK4QE?= =?us-ascii?Q?rc7/D5SsDDomAVZkFmPT2qhAVeG0JihurwfVna7p2J93yuQw1bHaNPOQkNG7?= =?us-ascii?Q?sU7Qlt5yjnA7RtMMdXZOantamAES0Hm/oiS6pm7ZDLNR8CI8nYbAp5bH/Uzw?= =?us-ascii?Q?jfqUUoHziI9vP7R/pQ+/+9geibeNTbxbJrwad1QxpMiZgvR1aiGW0E5MZ2Gy?= =?us-ascii?Q?L5COrMarktRLmQkdXrmx/Nge6XDSCd++FmNRQM9ro7IKQsdVP2DhvxQx24OR?= =?us-ascii?Q?W1td2PtSGPz+azlFkuKmD2+Gb/Bu+zvk1QLXnn32AKdFcXYPrhemJZw/E+TC?= =?us-ascii?Q?dK1ohTeHKsOBApn+oIrr4hqNY+2uyg8MAlZ9D28piims2+5Pjnz6Cd+8ZQej?= =?us-ascii?Q?JiwG6qGFRUnV9yiID0SQYrP966rzwQvJ+l+3UoUEFTuUQI0prvuNUY1Oi+xO?= =?us-ascii?Q?V3U3XBKhuQIZT4Cr+BiCOJXiK9UHEA5GjIHt9XTr7Ehqc03X8RjAW3EdAPGq?= =?us-ascii?Q?R9NpxVWPyt3/HM5VGSJiXCwf/NIDIoGp40sdfhgVBv11zZQvNC/OUO3y5Ebx?= =?us-ascii?Q?Gw4xlDkpyE8+yPHuMCNUtequqvT+JOn7NHT1iN95GcfmTvxrVDcp+f6z3/UE?= =?us-ascii?Q?6SOlpQlZyruY/ojYnIvlTpfBQKKnG3fBZFJ7Gm7qWtB0WaztNKjqZ86eDU4T?= =?us-ascii?Q?nfw+hOU3egf3kxZ79EjcZScGKPWMm5TwEW0JlspKnJuHPe9qhdNxXM3xyjuy?= =?us-ascii?Q?QSMjNIIg5JF3XwTFp3+e2rsBj466nhU+uB+4rj9LDnyvxaRZNuRtYE5H+HzG?= =?us-ascii?Q?t0qXxwiUClOowF/lkH8VP7MlTFMM9NH4x4ecAfVRzOHyS9WYhON9lcZRY8wn?= =?us-ascii?Q?ZoFDzuaMdCzEi0vLm5FLuZ/AwZCwc892nRhvxlOehA+md+SYG6J9fTqLlt5T?= =?us-ascii?Q?rU7n/qr+EvAFjQ+1/tAKLbXk3iGfKS2Y53vrfZGKk6haypbUQuMq4eMmPpAr?= =?us-ascii?Q?HgngmY6HYqD0mNURDaFAUd2Prq3TF1ANoSsYeSQg5Lc7r9o+z6E6tiYuZjy8?= =?us-ascii?Q?63x3UKrZb9VDeKUNyNrxuTCEh7UHdpNK3rN2D5UX5pPVzTmofPAksuU3q/mM?= =?us-ascii?Q?ml6TN7f0P4LUcG2NFQnIkE/qgTRbVPnLgNfJEzZfHLHCPJVzoYclT6sNz/Vc?= =?us-ascii?Q?Bx4GaPCuztJFxOJPB5l1OAXr6sV9I/buNIsZNQWA/0yGRJEHIIT3f2ZfUAOF?= =?us-ascii?Q?5KkkLRr3NXDBQHJoRrV9QhhgzyLydmqq2G1mD3WrUe+71SYoKhC8z5B1BRac?= =?us-ascii?Q?9oYF2e4WX0w+F6gSDCIthfzNEbWYz9wRHVM2K/8RFBzf4GWhgXS5/GW04Uhh?= =?us-ascii?Q?jSS8Zi0MzaJMOmm5jCDnkBYQUyHCPhzVVxlBIxC0Y+5dIQPrD2HSsPFxJg+8?= =?us-ascii?Q?koiJdgz/vzbKn7yfslF+PtUVZ8h+KH2ShpB9UAZeRPVoHjnmWOioB2OQ7RhP?= =?us-ascii?Q?0EeaYrzw7fRdC5bNA3wrko89vJivXXXOlt3nII62?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3b6e3a6b-6159-4bd6-cad1-08de2075f0cc X-MS-Exchange-CrossTenant-AuthSource: DB9PR04MB9626.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Nov 2025 16:26:45.9152 (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: MmlprQrey1CJUCbHBgK9ZAv4IG420aXJIInUGXPmc7EphzyGaYUAH0w1aTdrZao765VmI1qHt82U60c5j2z0GA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM7PR04MB6967 On Fri, Nov 07, 2025 at 10:13:19AM +0530, Manivannan Sadhasivam wrote: > If there is no device available under the Root Ports, there is no point in > sending PME_Turn_Off and waiting for L2/L3 transition during suspend, it > will result in a timeout. Hence, skip those steps if no device is available > during suspend. > > During resume, do not wait for the link up if there was no device connected > before suspend. It is very unlikely that a device will get connected while > the host system was suspended. > > Signed-off-by: Manivannan Sadhasivam > --- > drivers/pci/controller/dwc/pcie-designware-host.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c > index 20c9333bcb1c..5a39e7139ec9 100644 > --- a/drivers/pci/controller/dwc/pcie-designware-host.c > +++ b/drivers/pci/controller/dwc/pcie-designware-host.c > @@ -20,6 +20,7 @@ > #include > > #include "../../pci.h" > +#include "../pci-host-common.h" > #include "pcie-designware.h" > > static struct pci_ops dw_pcie_ops; > @@ -1129,6 +1130,9 @@ int dw_pcie_suspend_noirq(struct dw_pcie *pci) > u32 val; > int ret; > > + if (!pci_root_ports_have_device(pci->pp.bridge->bus)) > + goto stop_link; > + > /* > * If L1SS is supported, then do not put the link into L2 as some > * devices such as NVMe expect low resume latency. > @@ -1162,6 +1166,7 @@ int dw_pcie_suspend_noirq(struct dw_pcie *pci) > */ > udelay(1); I think move pme_turn_off() to helper funciton will make code look better if (pci_root_ports_have_device()) { ret = dwc_pme_turn_off(); if (ret) return ret; }; > > +stop_link: > dw_pcie_stop_link(pci); > if (pci->pp.ops->deinit) > pci->pp.ops->deinit(&pci->pp); > @@ -1195,6 +1200,14 @@ int dw_pcie_resume_noirq(struct dw_pcie *pci) > if (ret) > return ret; > > + /* > + * If there was no device before suspend, skip waiting for link up as > + * it is bound to fail. It is very unlikely that a device will get > + * connected *during* suspend. I think it should use certern term. the a device will not get linkup during suspend, if this happen, it is a new hotjoin device after system resume. Frank > + */ > + if (!pci_root_ports_have_device(pci->pp.bridge->bus)) > + return 0; > + > ret = dw_pcie_wait_for_link(pci); > if (ret) > return ret; > -- > 2.48.1 >