Re: Titan Ridge xHCI may stop to working after re-plugging the dock

[Kai-Heng Feng <kai.heng.feng@canonical.com>]

at 22:45, Mathias Nyman <mathias.nyman@linux.intel.com> wrote:

> On 22.7.2019 12.44, Kai-Heng Feng wrote:
>>>>>>> Hi Mika and Mathias,
>>>>>>>
>>>>>>> I’ve filed a bug [1] which renders docking station unusable.
>>>>>>>
>>>>>>> I am not sure it's a bug in PCI, Thunderbolt or xHCI so raise the  
>>>>>>> issue
>>>>>>> to
>>>>>>> you both.
>>>>>>>
>>>>>>> [1] https://bugzilla.kernel.org/show_bug.cgi?id=203885
>>>>>>>
>>>>>>> Kai-Heng
>>>>
>>>> I upgraded the system firmware, TBT firmware and docking station  
>>>> firmware
>>>> to latest, and used latest mainline kernel.
>>>> Now the issue can be reproduced at the very first time I plugged the
>>>> docking station.
>> Request log attached to Bugzilla.
>
> After docking station unplug we see Transfer errors from
> devices connected to Titan Ridge xHC, driver tries to recover, fails,
> usb devices are disconnected.
>
> After this xhci driver runtime suspends xHC controller as runtime pm is  
> allowed
> by default for Titan Ridge xHC controllers.
>
> Interesting parts from log:
>
>>>> Unplug Docking Station <<<
>
> [  328.102279] xhci_hcd 0000:39:00.0: Transfer error for slot 36 ep 6 on  
> endpoint
> [  328.118279] xhci_hcd 0000:39:00.0: Transfer error for slot 36 ep 6 on  
> endpoint
> [  328.134291] xhci_hcd 0000:39:00.0: Transfer error for slot 36 ep 6 on  
> endpoint
> [  328.150355] xhci_hcd 0000:39:00.0: Transfer error for slot 36 ep 6 on  
> endpoint
> [  328.166342] xhci_hcd 0000:39:00.0: Transfer error for slot 36 ep 6 on  
> endpoint
> [  332.178710] usb usb4-port2: Cannot enable. Maybe the USB cable is bad?
> [  332.178765] usb 4-2: USB disconnect, device number 35
> [  332.178769] usb 4-2.3: USB disconnect, device number 36
> [  332.179973] usb 4-2.4: USB disconnect, device number 37
> [  332.414618] xhci_hcd 0000:39:00.0: set port remote wake mask, actual  
> port 0 status  = 0xe0002a0
> [  332.414639] xhci_hcd 0000:39:00.0: set port remote wake mask, actual  
> port 1 status  = 0xe0002b0
> [  332.414693] xhci_hcd 0000:39:00.0: xhci_hub_status_data: stopping port  
> polling.
> [  332.414703] xhci_hcd 0000:39:00.0: xhci_suspend: stopping port polling.
> [  332.414719] xhci_hcd 0000:39:00.0: // Setting command ring address to  
> 0x487da9001
>
>>>> Plug Docking Station <<<
>
> [  346.455568] pci_raw_set_power_state: 25 callbacks suppressed
> [  346.455574] xhci_hcd 0000:39:00.0: Refused to change power state,  
> currently in D3
> [  346.539451] xhci_hcd 0000:39:00.0: enabling device (0000 -> 0002)
> [  346.539482] xhci_hcd 0000:39:00.0: // Setting command ring address to  
> 0x487da903f
> [  346.539487] xhci_hcd 0000:39:00.0: WARN: xHC restore state timeout
> [  346.539489] xhci_hcd 0000:39:00.0: PCI post-resume error -110!
> [  346.539490] xhci_hcd 0000:39:00.0: HC died; cleaning up
>
>>>> We don't have 0000:39:00 anymore <<<
>
> When docking station is plugged back we try to resume Titan Ridge xHC,
> PCI log shows that changing power state to D0 failed, xHC is still in D3.
> Resume process continues anyway, and xhci driver tries to restore state,  
> but fails.
> Usb core will assume HC died if the pci resume callback failed
>
> Does disabling runtime PM for Titan Ridge xHC help?

Yes, disabling runtime PM can workaround this issue.

Kai-Heng

>
> -Mathias