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

From: Prashanth K
Date: Tue Mar 25 2025 - 11:02:16 EST




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
>>
>> Pratham Pratap (2):
>> arm64: dts: qcom: qcs615: Add snps,dis_u3_susphy_quirk
>> arm64: dts: qcom: qdu1000: Add snps,dis_u3_susphy_quirk
>
> Are there more targets affected, from the list of the ones currently
> supported upstream?
>
> Konrad

My initial plan was to add it for all the QC platforms, but wasn't
confident enough about it. Because we have seen the issue only on these
targets and hence tested only on these.

Regards,
Prashanth K