CPU slows down as soon laptop unplugged, stays slow even if plugged back in

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15

I’ve done some tries on my system

  • The problem also occur with linux 5.7.15.
  • The problem occur only at boot time. Plug/Unplug AC doesn’t change CPU speed
  • cpupower frequency-info indicate me that the frequency is capped to 800Mhz. (whereas it’s a lot greater when laptop is booted plugged)
  • tlp is also running on my system. It seems to doesn’t detect plug/unplug state change.

I’ve tried to search for informations in logs but didn’t found interesting things, maybe I didn’t search well. (any idea for somethings to seek in logs ?)