Hi there!

I have Latitude 7520 laptop with i7-1185g7 and this model has a huge problem with CPU throttling.

Besides this model users report that 5420/7420 models affected too.

This laptops have a two issues:

1. Throttling to 400mhz after running power-intensive workloads for a short amount of time -- which caused by incorrect work of legacy interface. This issue can be resolved by blacklisting "intel_rapl_msr" module or install intel/thermald v2.4.6. 
2. The same issue but cpu stuck on 1800mhz -- it is another issue and currently I haven't any idea how resolve it. Looks like something from firmware locks CPU power.

Message from Intel developer(pls see here) :

The problem is that TMEM sensor reaches its limits of 42C in 4 seconds, so the system is throttled from max power. Even at the start the temperature is 39C. So not much margin. Not
sure what can be done here

So I am trying to find and solve this problem. Maybe someone from Dell can help. A lot of users buy Latitude laptops for work with Linux and as I can see Dell sells linux version of this laptops.

What I see currently:

• In Windows it works correctly(3.3-4.8ghz on max load)
• Latest mainline kernel(`5.13.0-1-mainline`) doesn't fix it
• Latest bios doesn't fix it(1.7.1 for my laptop)
• It depends on laptop vendor. I have MSI laptop with the same i7-1185g7 and it works properly, one difference is: Dell show "base_frequency" as 1800mhz, MSI as 3000mhz. Maybe it's related
• Load/Unload modules, disabling intel_pstate, tune tdp limits, changing thermal mode(quiet,cool,balanced,performance) doesn't affect this problem

Related links:

• Dell Lattitude 5420 (TGL) throttled to 400MHz CPU / 100MHz GPU after 30s #293
• Dell Latitude 5420 (i7-1185g7) Power limited #255 
• Latitude 7420 throttled to 55C on Linux. Cant watch 4K videos.
   

I will be very appreciated if someone help me to resolve this issue. Thanks!