Re: [PATCH v2 1/1] usb: xhci: apply XHCI_AVOID_BEI quirk to all Intel xHCI controllers

From: Alistair Grant
Date: Mon Mar 16 2015 - 10:31:57 EST


On Mon, Mar 16, 2015 at 1:55 PM, Mathias Nyman
<mathias.nyman@xxxxxxxxxxxxxxx> wrote:
> On 15.03.2015 21:18, Alistair Grant wrote:
>> On Sun, Mar 15, 2015 at 3:54 PM, Alistair Grant <akgrant0710@xxxxxxxxx> wrote:
>>> On Thu, Mar 12, 2015 at 8:14 PM, Alistair Grant <akgrant0710@xxxxxxxxx> wrote:
>>>> On Thu, Mar 12, 2015 at 11:15 AM, Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> wrote:
>>>>> When a device with an isochronous endpoint is plugged into the Intel
>>>>> xHCI host controller, and the driver submits multiple frames per URB,
>>>>> the xHCI driver will set the Block Event Interrupt (BEI) flag on all
>>>>> but the last TD for the URB. This causes the host controller to place
>>>>> an event on the event ring, but not send an interrupt. When the last
>>>>> TD for the URB completes, BEI is cleared, and we get an interrupt for
>>>>> the whole URB.
>>>>>
>>>>> However, under Intel xHCI host controllers, if the event ring is full
>>>>> of events from transfers with BEI set, an "Event Ring is Full" event
>>>>> will be posted to the last entry of the event ring, but no interrupt
>>>>> is generated. Host will cease all transfer and command executions and
>>>>> wait until software completes handling the pending events in the event
>>>>> ring. That means xHC stops, but event of "event ring is full" is not
>>>>> notified. As the result, the xHC looks like dead to user.
>>>>>
>>>>> This patch is to apply XHCI_AVOID_BEI quirk to Intel xHC devices. And
>>>>> it should be backported to kernels as old as 3.0, that contains the
>>>>> commit 69e848c2090a ("Intel xhci: Support EHCI/xHCI port switching.").
>>>>>
>>>>> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
>>>>> Cc: stable@xxxxxxxxxxxxxxx
>>>>> ---
>>>>> drivers/usb/host/xhci-pci.c | 2 +-
>>>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
>>>>> index fd53c9e..2af32e2 100644
>>>>> --- a/drivers/usb/host/xhci-pci.c
>>>>> +++ b/drivers/usb/host/xhci-pci.c
>>>>> @@ -115,6 +115,7 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
>>>>> if (pdev->vendor == PCI_VENDOR_ID_INTEL) {
>>>>> xhci->quirks |= XHCI_LPM_SUPPORT;
>>>>> xhci->quirks |= XHCI_INTEL_HOST;
>>>>> + xhci->quirks |= XHCI_AVOID_BEI;
>>>>> }
>>>>> if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
>>>>> pdev->device == PCI_DEVICE_ID_INTEL_PANTHERPOINT_XHCI) {
>>>>> @@ -130,7 +131,6 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
>>>>> * PPT chipsets.
>>>>> */
>>>>> xhci->quirks |= XHCI_SPURIOUS_REBOOT;
>>>>> - xhci->quirks |= XHCI_AVOID_BEI;
>>>>> }
>>>>> if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
>>>>> pdev->device == PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_XHCI) {
>>>>> --
>>>>> 2.1.0
>>>>>
>>>>> --
>>>>
>>>> This works for me...
>>>>
>>>> Computer: Dell XPS13 9333
>>>> USB controller: Intel Corporation 8 Series USB xHCI HC (rev 04)
>>>> (prog-if 30 [XHCI])
>>>> Kernel: 3.19.1
>>>> USB Device: Hauppauge USB-Live2
>>>>
>>>> Please let me know if I can help in any other way.
>>>>
>>>> Tested-by: Alistair Grant <akgrant0710@xxxxxxxxx>
>>>
>>> Just FYI...
>>>
>>> I was able to test this on a slightly older laptop that had both USB2
>>> and USB3 ports and can confirm that it also works there:
>>>
>>> 00:14.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset
>>> Family USB xHCI Host Controller (rev 04)
>>
>> It looks like I may have signed-off a little too soon. While the patch is
>> working correctly if the Hauppauge Live2 is plugged in after the system has
>> booted and settled down (my normal use case), it fails if the Live2 is
>> plugged in while the system is booted up.
>>
>> Unplugging the Live2 after recording (which appears to succeed from the
>> command line, but had no audio), executing lsusb just hangs.
>>
>> I've included what I think is the relevant portions of /var/log/syslog
>> below. If you'd like the entire log file posted somewhere please let me
>> know.
>
> Hi
>
> What kernel did you try this patch on?
>
> The output look a bit like the regression in 4.0-rc3 caused by:
> commit 27082e2654dc148078b0abdfc3c8e5ccbde0ebfa
> xhci: Clear the host side toggle manually when endpoint is 'soft reset'
>
> which will be reverted (in 4.0-rc5 I hope).
>
> If you boot the same base kernel without the patch does it work then?
>
> -Mathias
>

Hi Mathias,

This is on top of 3.19.1 with only the XHCI_AVOID_BEI quirk patch applied.

If you'd like me to try it against 4.0-rc3, 4 or 5, please let me know.

Thanks,
Alistair
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