Solved How can I see the real CPU frequency in Turbo mode (max freq + 1)?

pcm.x shows relative CPU frequency. The user must be in the group kmem.
EDIT performance_cpu_freq="HIGH" is not needed to get Turbo mode, but instead
sysrc performance_cx_lowest=Cmax & sysrc economy_cx_lowest=Cmax, because the Turbo mode is governed by CPU C-states.