On Wed May 28, 2025 at 9:52 AM BST, Dmitry Baryshkov wrote:

On Wed, May 28, 2025 at 01:31:18AM +0100, Alexey Klimov wrote:

quoted

Add the SM6115 MDSS compatible to clients compatible list, as it also
needs that workaround.
Without this workaround, for example, QRB4210 RB2 which is based on
SM4250/SM6115 generates a lot of smmu unhandled context faults during
boot:

arm_smmu_context_fault: 116854 callbacks suppressed
arm-smmu c600000.iommu: Unhandled context fault: fsr=0x402,
iova=0x5c0ec600, fsynr=0x320021, cbfrsynra=0x420, cb=5
arm-smmu c600000.iommu: FSR    = 00000402 [Format=2 TF], SID=0x420
arm-smmu c600000.iommu: FSYNR0 = 00320021 [S1CBNDX=50 PNU PLVL=1]
arm-smmu c600000.iommu: Unhandled context fault: fsr=0x402,
iova=0x5c0d7800, fsynr=0x320021, cbfrsynra=0x420, cb=5
arm-smmu c600000.iommu: FSR    = 00000402 [Format=2 TF], SID=0x420

and also leads to failed initialisation of lontium lt9611uxc driver
and gpu afterwards:

Nit: there is nothing failing the lt9611uxc on its own. binding all MDSS
components (triggered by lt9611uxc attaching to the DSI bus) produces
the failure.

Oh, I didn't mean to express that something failed in lt9611uxc itself, I
was just trying to list observed problems.
Apart from hdmi bridge and gpu the failed component will be soundcard driver
since it depends on lt9611uxc.. So, if you have rewording in mind feel free
to suggest it.

Or maybe something like this will look better:
and also failed initialisation of lontium lt9611uxc, gpu and dpu is observed:
  (kernel trace as in the original email)

[..]

Reviewed-by: Dmitry Baryshkov <redacted>

I'd also propose:

Fixes: 3581b7062cec ("drm/msm/disp/dpu1: add support for display on SM6115")

This way this is going to be fixed for all platforms using display on
SM6115.

Yes. Thanks. Checkpatch suggested "Fixes" tag but it was unclear when it
started to horribly fail during boot -- sometime around 6.14 or 6.15 cycle.

Best regards,
Alexey