figured it out, mesa 25 started using afbc on mediatek but it doesn't work properly, mediatek disabled it downstream temporarily https://gitlab.collabora.com/mediatek/aiot/linux/-/merge_requests/9
HACK: MTK: Disable AFBC support (!9) · Merge requests · MediaTek / aiot / linux · GitLab

Starting with Mesa 25 AFBC will get more eagerly used. Unfortunately it seems both primary and overlay planes on Genio 700 and Genio 1200 are broken in this...

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@weirdtreething @domi you can set PAN_MESA_DEBUG=noafbc as a workaround that doesn't require a kernel patch
Commits · wip/adalessandro/mediatek-fix-afbc · MediaTek / aiot / linux · GitLab

MediaTek SoC Upstream Integration

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