Re: [PATCH v1 0/5] Add snps,dis_u3_susphy_quirk for some QC targets

From: Dmitry Baryshkov
Date: Wed Mar 26 2025 - 10:36:17 EST


On Wed, Mar 26, 2025 at 10:52:46AM +0530, Krishna Kurapati wrote:
>
>
> On 3/26/2025 5:51 AM, Dmitry Baryshkov wrote:
> > On Tue, Mar 25, 2025 at 08:31:55PM +0530, Prashanth K wrote:
> > >
> > >
> > > On 25-03-25 08:11 pm, Konrad Dybcio wrote:
> > > > On 3/25/25 1:30 PM, Prashanth K wrote:
> > > > > During device mode initialization on certain QC targets, before the
> > > > > runstop bit is set, sometimes it's observed that the GEVNTADR{LO/HI}
> > > > > register write fails. As a result, GEVTADDR registers are still 0x0.
> > > > > Upon setting runstop bit, DWC3 controller attempts to write the new
> > > > > events to address 0x0, causing an SMMU fault and system crash. More
> > > > > info about the crash at [1].
> > > > >
> > > > > This was initially observed on SM8450 and later reported on few
> > > > > other targets as well. As suggested by Qualcomm HW team, clearing
> > > > > the GUSB3PIPECTL.SUSPHY bit resolves the issue by preventing register
> > > > > write failures. Address this by setting the snps,dis_u3_susphy_quirk
> > > > > to keep the GUSB3PIPECTL.SUSPHY bit cleared. This change was tested
> > > > > on multiple targets (SM8350, SM8450 QCS615 etc.) for over an year
> > > > > and hasn't exhibited any side effects.
> > > > >
> > > > > [1]: https://lore.kernel.org/all/fa94cbc9-e637-ba9b-8ec8-67c6955eca98@xxxxxxxxxxx/
> > > > >
> > > > > Prashanth K (3):
> > > > > arm64: dts: qcom: sm8150: Add snps,dis_u3_susphy_quirk
> > > > > arm64: dts: qcom: sm8350: Add snps,dis_u3_susphy_quirk
> > > > > arm64: dts: qcom: sm8450: Add snps,dis_u3_susphy_quirk
> >
> > It is hard to belive that this quirk is to be set for SM8150, SM8350,
> > SM8450, but not SM8250.
> >
>
> At the moment we wanted to add this quirk for targets where issue has shown
> up either internal to QC or at customer's end. But the issue didn't come up
> on SM8250/ SM8550/ SM8650 so far either from customer end or ours. Would
> like to update for other targets on need basis.

I'm not questioning SM8[56]50, but not seeing SM8250 here is really
doubtful.

--
With best wishes
Dmitry