Re: Cpufreq drivers not working on T480S

[Milky <milky_way_303030@xxxxxxxxx>]

On Wednesday, January 14th, 2026 at 11:12 AM, Jan Beulich <jbeulich@xxxxxxxx> 
wrote:

>
>
> On 14.01.2026 11:58, Milky wrote:
>
> > Just wanted to update this thread to say that now another T480 user (the 
> > T480 is a very similar model to my T480S) using the release builds of 
> > libreboot (as of 26.01 RC1) also has the entries missing from the ACPI 
> > tables. That discussion was here 
> > https://codeberg.org/libreboot/lbmk/issues/394. So this confirms that I'm 
> > running a standard libreboot, rather than a bad build.
> >
> > Do you think there is any way to avoid the underclocking issue with Xen on 
> > such devices/firmware?
>
>
> In principle there is, but in the absence of ACPI data that means holding 
> model-
> specific data in Xen. Which iirc is what the intel-pstate driver in Linux does
> (using ACPI info nowadays only as "auxiliary" data). But I may be wrong there,
> as it has been a long time since I last looked at that driver.
>
> Jan



In that case, would you say this is settled now? Would it make sense to report 
back to the QubesOS community that librebooted T480/S will run underclocked, 
due to the missing data in ACPI tables and lack of native support in Xen? This 
information is important, as the device is only barely usable.