Re: [REGRESSION] Intel Wireless adapter is not detected until suspending to RAM and resuming

[Bjorn Helgaas <helgaas@kernel.org>]

[+cc Lukas, beginning of thread with complete dmesg log:
https://lore.kernel.org/r/owewi3sswao4jt5qn3ntm533lvxe3jlovhjbdufq3uedbuztxt@76nft22vboxv]

On Mon, Oct 20, 2025 at 11:37:43AM -0500, Mario Limonciello (AMD) (kernel.org) wrote:
> On 10/20/2025 7:56 AM, Adrià Vilanova Martínez wrote:
> > On Sun, Oct 19, 2025 at 07:25:08PM -0500, Mario Limonciello wrote:
> > > Thanks, knowing that pcie_aspm=off helps I think we should compare output
> > > for:
> > > 
> > > # sudo lspci -vvnn
> > 
> > Sure, I'm attaching the outputs of this command for all the scenarios.
> > There are some differences, so it seems promising.
> 
> Surprisingly there is nothing different about ASPM though.  It's all PCI-PM
> differences.
> 
> Looking at your log again I noticed this from the bridge:
> 
> pcieport 0000:00:1c.0: pciehp: Slot(0): Card not present
> pcieport 0000:00:1c.0: pciehp: Slot(0): Card present
> pcieport 0000:00:1c.0: pciehp: Slot(0): Link Up
> ...
> pcieport 0000:00:1c.0: pciehp: Slot(0): No device found
> ...
> (suspend)
> ...
> pcieport 0000:00:1c.0: pciehp: Slot(0): Card present
> pcieport 0000:00:1c.0: pciehp: Slot(0): Link Up

This seems wrong.  The PCI core definitely enumerated the wifi device,
but it seems like there's some pciehp confusion about presence/link
up/etc, and we couldn't actually use it until after the
suspend/resume:

  [    0.113379] pci 0000:00:1c.0: [8086:9d10] type 01 class 0x060400 PCIe Root Port
  [    0.113403] pci 0000:00:1c.0: PCI bridge to [bus 01]
  [    0.113409] pci 0000:00:1c.0:   bridge window [mem 0x91000000-0x910fffff]
  [    0.115692] pci 0000:01:00.0: [8086:095a] type 00 class 0x028000 PCIe Endpoint
  [    0.115830] pci 0000:01:00.0: BAR 0 [mem 0x91000000-0x91001fff 64bit]
  [    0.196539] pcieport 0000:00:1c.0: pciehp: Slot #0 AttnBtn- PwrCtrl- MRL- AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
  [    0.196802] pcieport 0000:00:1c.0: pciehp: Slot(0): Card not present
  [    0.196925] pcieport 0000:00:1c.0: pciehp: Slot(0): Card present
  [    0.196927] pcieport 0000:00:1c.0: pciehp: Slot(0): Link Up
  [    1.400127] pcieport 0000:00:1c.0: pciehp: Slot(0): No device found
  [   50.295404] ACPI: PM: Preparing to enter system sleep state S3

  [   50.314754] ACPI: PM: Waking up from system sleep state S3
  [   50.328910] pcieport 0000:00:1c.0: pciehp: Slot(0): Card present
  [   50.328914] pcieport 0000:00:1c.0: pciehp: Slot(0): Link Up
  [   50.454011] pci 0000:01:00.0: [8086:095a] type 00 class 0x028000 PCIe Endpoint
  [   50.454135] pci 0000:01:00.0: BAR 0 [mem 0x91000000-0x91001fff 64bit]
  [   50.833621] iwlwifi 0000:01:00.0: Detected crf-id 0x0, cnv-id 0x0 wfpm id 0x0
  [   50.833632] iwlwifi 0000:01:00.0: PCI dev 095a/9e10, rev=0x210, rfid=0xd55555d5
  [   50.833636] iwlwifi 0000:01:00.0: Detected Intel(R) Dual Band Wireless-AC 7265

I don't have any good ideas.

Bjorn