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TGL-UP3: keyboard typing lag and screen tearing on 4K monitor with PSR2 enabled.

I got a Lenovo laptop with a TGL-UP3(i7-1185G7) CPU and a 4K monitor, and there have 2 issues on Linux:

  1. keyboard typing lag, it's pretty easy to reproduce and the user experience is very bad.
  2. sometimes the screen will tearing, it will reproduce after switching in some opened windows.

I tried latest vanilla Linux kernel (5.11) and Ubuntu drm-tip daily kernel(https://kernel.ubuntu.com/~kernel-ppa/mainline/drm-tip/current/), both can reproduce the two issues.

The only way to workaround is to disable PSR2, by "echo 0x1 > /sys/kernel/debug/dri/0/i915_edp_psr_debug" or by add "add i915.enable_psr=0" to kernel cmdline.

some debug files(cpuinfo, dmesg, edid, lspci, xrandr) attached. psr2-debug.tgz

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