I am running xubuntu 18.04 (kernel version 4.15.0-36) on a Lenovo yoga 11e laptop. After resuming from suspend, frequency scaling works fine on cores 0 and 1 but cores 2 and 3 are stuck at 480 MHz. I have attached the output of cpufreq-info while the machine is being stressed with stress -c 4. I have also attached /proc/cpuinfo.

The same behaviour appears regardless of which cpu frequency governor is set, and using either the intel_pstate driver or the acpi-cpufreq driver. The frequency cannot be set manually with cpufreq-set. As recommended in other threads, I have tried setting /sys/module/processor/parameters/ignore_ppc to 1, but this does not help. Some other threads recommended checking the output of rdmsr -a 0x19a. Here is the output (after resuming from suspend):

rdmsr -a 0x19a
0
0
0
0

Any help would be appreciated.

Attached Files

	cpufreq-info.log (4.1 KB, 10 views)
	cpuinfo.log (3.9 KB, 10 views)

Lenovo and Thinkpads have many kernel options applying to them specifically. They were always non standard from the get-go. Other laptops are likewise (e.g. Sony Viao). Kernels can't always enable these quirks because a) They will break or reduce performance for the majority of bog standard chipsets or b) They will freak other non standard stuff.

From There's Documentation about thinkpad-acpi, there's stuff in the acpi, all input/hid/network stuff.

You could do worse than check out how the land lies there for you.

Attached is the output of grep -ir -A 2 lenovo/usr/src/linux*/*
Is there anything here that looks relevant?

Attached Files

drivers.log (16.3 KB, 12 views)

I can grep my own kernel, but thanks. The acpi stuff looks relevant. Also the Documentation/laptops/thinkpad-acpi.txt. You need to find out if your model needs tweaks to the existing acpi settings.

I'm not a thinkpad/lenovo owner, btw.

Lenovo, Dell and HP are such massively huge PC manufacturers that they can compel IC manufacturers to produce ICs just for their products. Such components have no published data sheets, so no one can find out about them! Also, being behemoths in PC manufacturing, they have the resources to add custom drivers and software that also have no documentation available to the general public.

Every PC I ever owned by Dell, IBM, Lenovo or HP had proprietary hardware quirks when used with Linux. The best one can do is plead their case to the manufacturer for Linux support.

It's not that the big players compel manufacturers, I thought, but that they had the turnover to invest. For about $25k up, you can get an Application Specific Integrated Circuit (ASIC) designed for a specific fab size. The model is: design -->FPGA prototype --> ASIC. That gets you tooling to build your IC. That's how things are done. All those big square chips in mobile phones & pcs are ASICs. They incorporate IP cores from many other smaller chips perhaps in many cases once sold as discrete hardware.

Now an ASIC on Samsung's 11 or 14nm fab would be pricier than an older slower design running perhaps on 40nm fab, because the resulting device would be slower, and consume more current.