Re: [PATCH] usb: dwc3: Disable AutoRetry controller feature for dwc_usb3 v2.00a

[Jakub Vaněk]

On Wed, 2023-07-05 at 22:47 +0000, Thinh Nguyen wrote:
> Hi,
> 
> On Sat, Jul 01, 2023, Jakub Vanek wrote:
> > AutoRetry has been found to cause issues in this controller revision.
> > This feature allows the controller to send non-terminating/burst retry
> > ACKs (Retry=1 and Nump!=0) as opposed to terminating retry ACKs
> > (Retry=1 and Nump=0) to devices when a transaction error occurs.
> > 
> > Unfortunately, some USB devices do not retry transfers when
> > the controller sends them a non-terminating retry ACK. After the transfer
> > times out, the xHCI driver tries to resume normal operation of the
> > controller by sending a Stop Endpoint command to it. However, this
> > revision of the controller fails to respond to that command in this
> > state and the xHCI driver therefore gives up. This is reported via dmesg:
> > 
> > [sda] tag#29 uas_eh_abort_handler 0 uas-tag 1 inflight: CMD IN
> > [sda] tag#29 CDB: opcode=0x28 28 00 00 69 42 80 00 00 48 00
> > xhci-hcd: xHCI host not responding to stop endpoint command
> > xhci-hcd: xHCI host controller not responding, assume dead
> > xhci-hcd: HC died; cleaning up
> > 
> > This problem has been observed on Odroid HC2. This board has
> > an integrated JMS578 USB3-to-SATA bridge. The above problem could be
> > triggered by starting a read-heavy workload on an attached SSD.
> > After a while, the host controller would die and the SSD would disappear
> > from the system.
> > 
> > Reverting b138e23d3dff ("usb: dwc3: core: Enable AutoRetry feature in
> > the controller") stopped the issue from occurring on Odroid HC2.
> > As this problem hasn't been reported on other devices, disable
> > AutoRetry just for the dwc_usb3 revision v2.00a that the board SoC
> > (Exynos 5422) uses.
> > 
> > Fixes: b138e23d3dff ("usb: dwc3: core: Enable AutoRetry feature in the controller")
> > Link: https://urldefense.com/v3/__https://lore.kernel.org/r/a21f34c04632d250cd0a78c7c6f4a1c9c7a43142.camel@xxxxxxxxx/__;!!A4F2R9G_pg!YWgF6oqfuVY6xstZmroukjlrwAFEYEQE8uj_iUu4fd10mnJxEPG345k75dMLLdNFP8rT1leok-aPNkz_FuAJ1zxnmw$ ;
> > Link: https://urldefense.com/v3/__https://forum.odroid.com/viewtopic.php?t=42630__;!!A4F2R9G_pg!YWgF6oqfuVY6xstZmroukjlrwAFEYEQE8uj_iUu4fd10mnJxEPG345k75dMLLdNFP8rT1leok-aPNkz_FuCzOGIVPA$ ;
> > Cc: stable@xxxxxxxxxxxxxxx
> > Cc: Mauro Ribeiro <mauro.ribeiro@xxxxxxxxxxxxxx>
> > Cc: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> > Suggested-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
> > Signed-off-by: Jakub Vanek <linuxtardis@xxxxxxxxx>
> > ---
> >  drivers/usb/dwc3/core.c | 10 ++++++++--
> >  1 file changed, 8 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> > index d68958e151a7..d742fc882d7e 100644
> > --- a/drivers/usb/dwc3/core.c
> > +++ b/drivers/usb/dwc3/core.c
> > @@ -1218,9 +1218,15 @@ static int dwc3_core_init(struct dwc3 *dwc)
> >                  * Host mode on seeing transaction errors(CRC errors or internal
> >                  * overrun scenerios) on IN transfers to reply to the device
> >                  * with a non-terminating retry ACK (i.e, an ACK transcation
> > -                * packet with Retry=1 & Nump != 0)
> > +                * packet with Retry=1 & Nump != 0).
> > +                *
> > +                * Do not enable this for DWC_usb3 v2.00a. This controller
> > +                * revision stops responding to Stop Endpoint commands if
> > +                * a USB device does not retry after a non-terminating retry
> > +                * ACK is sent to it.
> >                  */
> > -               reg |= DWC3_GUCTL_HSTINAUTORETRY;
> > +               if (!DWC3_VER_IS(DWC3, 200A))
> > +                       reg |= DWC3_GUCTL_HSTINAUTORETRY;
> >  
> >                 dwc3_writel(dwc->regs, DWC3_GUCTL, reg);
> >         }
> > -- 
> > 2.25.1
> > 
> 
> I brought up this inquiry internally. Please wait as I need to review
> this further. The handling for this may be different depending on the
> team's feedback.
> 

OK; feel free to contact me if I could be of any help.

> Thanks,
> Thinh

Thank you,
Jakub