Re: [PATCH v5 4/4] arm64: dts: qcom: add HDMI nodes for msm8998

Konrad Dybcio
2024-07-23T13:43:19Z

On 23.07.2024 3:38 PM, Marc Gonzalez wrote:
> On 23/07/2024 15:08, Konrad Dybcio wrote:
>
>> On 23.07.2024 2:57 PM, Marc Gonzalez wrote:
>>
>>> On 23/07/2024 13:45, Konrad Dybcio wrote:
>>>
>>>> On 23.07.2024 11:59 AM, Dmitry Baryshkov wrote:
>>>>
>>>>> On Tue, 23 Jul 2024 at 12:48, Marc Gonzalez wrote:
>>>>>
>>>>>> On 16/07/2024 18:37, Dmitry Baryshkov wrote:
>>>>>>
>>>>>>> No, that's fine. It is the SMMU issue that Konrad has been asking you
>>>>>>> to take a look at.
>>>>>>
>>>>>> Context:
>>>>>>
>>>>>> [ 4.911422] arm-smmu cd00000.iommu: FSR = 00000402 [Format=2 TF], SID=0x0
>>>>>> [ 4.923353] arm-smmu cd00000.iommu: FSYNR0 = 00000021 [S1CBNDX=0 PNU PLVL=1]
>>>>>> [ 4.927893] arm-smmu cd00000.iommu: FSR = 00000402 [Format=2 TF], SID=0x0
>>>>>> [ 4.941928] arm-smmu cd00000.iommu: FSYNR0 = 00000021 [S1CBNDX=0 PNU PLVL=1]
>>>>>> [ 4.944438] arm-smmu cd00000.iommu: FSR = 00000402 [Format=2 TF], SID=0x0
>>>>>> [ 4.956013] arm-smmu cd00000.iommu: FSYNR0 = 00000021 [S1CBNDX=0 PNU PLVL=1]
>>>>>> [ 4.961055] arm-smmu cd00000.iommu: FSR = 00000402 [Format=2 TF], SID=0x0
>>>>>> [ 4.974565] arm-smmu cd00000.iommu: FSYNR0 = 00000021 [S1CBNDX=0 PNU PLVL=1]
>>>>>> [ 4.977628] arm-smmu cd00000.iommu: FSR = 00000402 [Format=2 TF], SID=0x0
>>>>>> [ 4.989670] arm-smmu cd00000.iommu: FSYNR0 = 00000021 [S1CBNDX=0 PNU PLVL=1]
>>>>>>
>>>>>>
>>>>>> As I mentioned, I don't think I've ever seen issues from cd00000.iommu
>>>>>> on my board.
>>>>>
>>>>> Interestingly enough, I can also see iommu errors during WiFi startup
>>>>> / shutdown on msm8998 / miix630. This leads me to thinking that it
>>>>> well might be that there is a missing quirk in the iommu driver.
>>>>>
>>>>>> I can test a reboot loop for a few hours, to see if anything shows up.
>>>>>
>>>>> Yes, please.
>>>>
>>>> Yeah I do trust you Marc that it actually works for you and I'm not
>>>> gonna delay this series because of that, but please go ahead and
>>>> reboot-loop your board
>>>>
>>>> 8998/660 is """famous""" for it's iommu problems
>>>
>>> [ 20.501062] arm-smmu 16c0000.iommu: Unhandled context fault: fsr=0x402, iova=0x00000000, fsynr=0x1, cbfrsynra=0x1900, cb=0
>>>
>>> I get the above warning pretty reliably.
>>> I don't think it's related to the issue(s) you mentioned.
>>> System just keeps plodding along.
>>
>> Yeah that one's "fine"
>
> I booted 40 times in a loop.
>
> `grep -a -i FSYNR console.logs` just returns the same 16c0000.iommu
> "Unhandled context fault" message 76 times (as above).
>
> NB: I have maxcpus=1 set in bootargs.
>
> Could the iommu issue be a race condition, NOT triggered when code
> runs with less parallelism?

No clue, can you try without maxcpus=1?

The thing will likely run slower (because reasons), but shouldn't
explode

Konrad