Re: Thunderbolt adapter fails to instantiate USB and device enumeration if already connected at boot time

[Lukas Wunner <lukas@wunner.de>]

On Mon, Jan 02, 2017 at 02:45:00PM -0700, Chris Murphy wrote:
> On Mon, Jan 2, 2017 at 2:28 PM, Alan Stern <stern@rowland.harvard.edu> wrote:
> > Considering that the failed boot log contains no USB messages at all,
> > and no messages referring to PCI bus 0000:37 (the bus associated with
> > the adapter), this certainly looks like a PCI problem.
> 
> I see these lines in the problem case, which don't occur in the working case.
> 
> [    0.561046] pci_bus 0000:37: busn_res: [bus 37-ff] end is updated to 37
> [    0.561047] pci_bus 0000:37: busn_res: can not insert [bus 37]
> under domain [bus 00-ff] (conflicts with (null) [bus 00-fe])

In the "failure dmesg" (with the adapter plugged in on boot), bus 37 is
considered a root bus:

[    0.560662] PCI: Discovered peer bus 37
[    0.560667] PCI: root bus 37: using default resources
[    0.560668] PCI: Probing PCI hardware (bus 37)
[    0.560695] ACPI: \: failed to evaluate _DSM (0x1001)
[    0.560698] PCI host bridge to bus 0000:37

Whereas in the "normal behaviour" dmesg (with the adapter plugged in
after booting Linux), bus 37 is below downstream port 0000:02:02.0
(this belongs to the PCIe switch of the Thunderbolt controller):

[   59.247680] pci 0000:02:02.0: scanning [bus 37-37] behind bridge, pass 0
[   59.247915] pci_bus 0000:37: scanning bus
[   59.247963] pci 0000:37:00.0: [8086:15b6] type 00 class 0x0c0330
[   59.248014] pci 0000:37:00.0: reg 0x10: [mem 0xc7f00000-0xc7f0ffff]
[   59.248360] pci 0000:37:00.0: supports D1 D2
[   59.248366] pci 0000:37:00.0: PME# supported from D0 D1 D2 D3hot D3cold
[   59.248379] pci 0000:37:00.0: PME# disabled
[   59.248951] pci_bus 0000:37: fixups for bus
[   59.248959] pci 0000:02:02.0: PCI bridge to [bus 37]
[   59.249117] pci 0000:02:02.0:   bridge window [mem 0xc7f00000-0xc7ffffff]
[   59.249135] pci_bus 0000:37: bus scan returning with max=37

Could be an error in the ACPI tables, could be a misconfiguration in
the EEPROM of the Thunderbolt controller.

Thanks,

Lukas