Performance governor does not set the maxmum frequency

I am trying to use the governor on performance mode, but everytime I check the frequency values I see a frequency less than the CPU frequency. I am using a Intel(R) Xeon(R) CPU E5-2650 v4 @ 2.20GHz

$ grep -E '^model name|^cpu MHz' /proc/cpuinfo
...
model name      : Intel(R) Xeon(R) CPU E5-2650 v4 @ 2.20GHz
cpu MHz         : 2502.455
model name      : Intel(R) Xeon(R) CPU E5-2650 v4 @ 2.20GHz
cpu MHz         : 2510.818
model name      : Intel(R) Xeon(R) CPU E5-2650 v4 @ 2.20GHz
cpu MHz         : 2510.623
model name      : Intel(R) Xeon(R) CPU E5-2650 v4 @ 2.20GHz
cpu MHz         : 1200.373
model name      : Intel(R) Xeon(R) CPU E5-2650 v4 @ 2.20GHz
cpu MHz         : 1200.297
model name      : Intel(R) Xeon(R) CPU E5-2650 v4 @ 2.20GHz
cpu MHz         : 1201.526
model name      : Intel(R) Xeon(R) CPU E5-2650 v4 @ 2.20GHz
cpu MHz         : 1200.133
...

First of all, I have set the governor in performance mode in /etc/default/cpufrequtils. Also, I got rid of the ondemand services. Furthermore, I have set energy_perf_bias to 0 for all cores

for cpu in /sys/devices/system/cpu/cpu{0..47}; do
    echo 0 > "$cpu/power/energy_perf_bias"
done

and I have set the min_perf_pct of intel_pstate driver to 100

echo 100 > /sys/devices/system/cpu/intel_pstate/min_perf_pct

Also from the kernel config I have set CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y

I have used the following grub options to boot the kernel

intel_pstate=no_hwp intel_idle.max_cstate=0 processor.max_cstate=1 idle=halt

But still the cores are not running all at the same maximum frequency.

I suspect the problem here is that the governor tries to go above the base frequency of 2.20GHz as its limits are between 1.2Ghz and 2.9Ghz. Therefore, probably the governor lowers the frequency of some cores to be within the TDP (Thermal design power).

Thus, to try to avoid that, I have disabled the turbo frequency

echo -n 1 > /sys/devices/system/cpu/intel_pstate/no_turbo

and set the minimum scaling frequency to 2.2GHz in /sys/devices/system/cpu/cpu*/cpufreq/scaling_min_freq but still there are cores which do not run at 2.2Ghz

$ cpufreq-info
...
analyzing CPU 12:
  driver: intel_pstate
  CPUs which run at the same hardware frequency: 12
  CPUs which need to have their frequency coordinated by software: 12
  maximum transition latency: 4294.55 ms.
  hardware limits: 1.20 GHz - 2.90 GHz
  available cpufreq governors: performance, powersave
  current policy: frequency should be within 2.20 GHz and 2.20 GHz.
                  The governor "performance" may decide which speed to use
                  within this range.
  current CPU frequency is 1.20 GHz.
...

How can I get all cores to run at 2.2GHz?

Thanks