Re: [PATCH 0/2] x86/cpu: P-state support for Lightning Mountain

From: srinivas pandruvada

Date: Mon Mar 09 2026 - 12:11:17 EST


On Mon, 2026-03-09 at 07:53 +0100, Martin Schiller wrote:
> On 2026-03-06 18:59, Rafael J. Wysocki wrote:
> > On Fri, Mar 6, 2026 at 9:27 AM Martin Schiller <ms@xxxxxxxxxx>
> > wrote:
> > >
> > > This patch set contains 2 commits to get P-state support for
> > > Intel /
> > > MaxLinear Lightning Mountain. The first adds the needed code to
> > > the
> > > intel_pstate driver. The second adds a workaround to the x86/cpu
> > > subsystem to enable EIST on all cpus.
> >
> > Can you please combine the patches?
> >
> > Or does the first one work just fine without the second one?
>
> Well, the first patch can basically be applied without the second
> one,
> but then frequency stepping will only work on the first cpu core.
>
> I split the two changes because they apply to different parts of the
> kernel sources.
>
> But you're probably right, and it makes sense to combine the two
> patches.
>
>
> BTW: The original code from the MaxLinear SDK enables EIST in the
> intel_pstate driver, but I don't think that's the right place for it.

This is a special case. But intel_pstate driver can be disabled from
kernel command line to use acpi cpufreq driver. So in that case
enabling in intel_pstate will not help.

Thanks,
Srinivas