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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Proofpoint-Spam-Info: AW1haW4tMjYwOTA5MDEyMSBTYWx0ZWRfX2Br3Ap0Pplyb 1wpYKmz6jcA4RFthacaMRv5o2k7S2rULPpGuPCnte4t5D9Bz073Qi6vFYmIVlOfzV2P6nMMLhfn c/SVyYzwgs3z9QPK474foimwWWn5uKY= X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwOTA5MDEyMSBTYWx0ZWRfX55oX0WclVWuW Zsw8wkkni5iRP8Mm987OwtdHTOqnJ12FnXqLDbTkJrJuQt33g/0DLBNGkOwOlAtw7UcM9OlgpHx 8vCHGy9CDPRI1TeXb1lw7O+R9zZoNhU7ZjSW1YIdtKhtdVZrlJ6Qewz6Qc9uAAC6xOVSC9SByo+ PgmRVIRpFMc26BbUsoEl00/wr+4w7tLQMUa+lRNhsj0SMu0EbwQlsqxVIK4ndcmtZX7Z2jjdJCB nfxVEiznO9Fe36o/51nqPCPhntipUqSltiRlIJUUYWg2bvjJIKtOZQ0RqVrCbGo+K3TfEGXJAcY 01W5LuUPFFvDA1rV1bDAOkRnisDP7LvrHsJdORFecMNtB/D02eX5z8M5fyBvIQf8HIcHbtuNzvz 8nY4Ig2TELXnB4SwBDrBaIpNFKLvT+X/DALMrcasQOjlbZbK9eH7sFPiFXap5MLK+zRQDLfRU9j 10nW4O4N7kSzQIW7Z+w== X-Authority-Analysis: v=2.4 cv=UeFhjqSN c=1 sm=1 tr=0 ts=6aa13ac1 cx=c_pps a=50t2pK5VMbmlHzFWWp8p/g==:117 a=PRfkaYvzSr8QmIIGAkY2Sg==:17 a=IkcTkHD0fZMA:10 a=VdqzKS8jKosA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=gowsoOTTUOVcmtlkKump:22 a=EUspDBNiAAAA:8 a=iI2QsGKwy_EL_xBlssYA:9 a=QEXdDO2ut3YA:10 a=IoWCM6iH3mJn3m4BftBB:22 X-Proofpoint-ORIG-GUID: p967EEkjSKXNRpVQo_JeZARCE5Z1KfnS X-Proofpoint-GUID: p967EEkjSKXNRpVQo_JeZARCE5Z1KfnS X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-09-08_03,2026-09-09_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 clxscore=1015 phishscore=0 lowpriorityscore=0 bulkscore=0 priorityscore=1501 malwarescore=0 adultscore=0 impostorscore=0 spamscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2609090121 On 9/5/26 2:48 AM, Krishna Chaitanya Chundru wrote: > dw_pcie_suspend_noirq() normally calls pci_host_common_d3cold_possible() > to check whether every downstream endpoint can be put into D3cold before > bothering to move the link to L2. If no endpoint supports it, the > function returns early and leaves the link up. > > Querying D3cold support during shutdown is actively harmful, not just > slow: pci_host_common_d3cold_possible() requires every active endpoint > to already be in PCI_D3hot, and returns false otherwise. If any endpoint > is still in D0 -- which is common, since endpoint drivers aren't > guaranteed to have suspended by the time the host's shutdown path runs > the check fails and dw_pcie_suspend_noirq() returns early without ever > moving the link to L2, leaving it up right up to the point where the > system cuts power/clocks to the controller. > > Add a "force_d3cold" flag to struct dw_pcie_rp that callers set > explicitly to force this behavior, rather than having > dw_pcie_suspend_noirq() infer the shutdown/reboot case itself from > system_state. Still call pci_host_common_d3cold_possible() > unconditionally, since it's also how "pme_capable" gets set, but ignore > its return value when force_d3cold is set and force L2 entry regardless. > > Signed-off-by: Krishna Chaitanya Chundru > --- > drivers/pci/controller/dwc/pcie-designware-host.c | 5 +++-- > drivers/pci/controller/dwc/pcie-designware.h | 1 + > 2 files changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c > index f5a38e6fd8d7..a8a3861c2956 100644 > --- a/drivers/pci/controller/dwc/pcie-designware-host.c > +++ b/drivers/pci/controller/dwc/pcie-designware-host.c > @@ -1224,14 +1224,15 @@ static int dw_pcie_pme_turn_off(struct dw_pcie *pci) > > int dw_pcie_suspend_noirq(struct dw_pcie *pci) > { > - bool pme_capable = false; > + bool d3cold, pme_capable = false; "d3cold_possible" or "_allowed" (although "_possible" follows the helper name so perhaps it's better) would be more descriptive here Konrad > int ret = 0; > u32 val; > > if (!dw_pcie_link_up(pci)) > goto stop_link; > > - if (!pci_host_common_d3cold_possible(pci->pp.bridge, &pme_capable)) > + d3cold = pci_host_common_d3cold_possible(pci->pp.bridge, &pme_capable); > + if (!d3cold && !pci->pp.force_d3cold) > return 0; > > if (pci->pp.ops->pme_turn_off) { > diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h > index a53ac27cd244..8becf4e62703 100644 > --- a/drivers/pci/controller/dwc/pcie-designware.h > +++ b/drivers/pci/controller/dwc/pcie-designware.h > @@ -471,6 +471,7 @@ struct dw_pcie_rp { > bool native_ecam; > bool skip_l23_ready; > bool skip_pwrctrl_off; > + bool force_d3cold; > }; > > struct dw_pcie_ep_ops { >