Add sections to the handbook on cpu frequency control

[allanjude]

Summary

covers cpufreq(4), est(4), and hwpstate_intel(4).

Add a link to hwpstate_intel(4) to the relnotes, as with the change, powerd(8) no longer functions on newer CPUs.

PR: 255324
Submitted By: Kyle Kneisl <[e-mail]>

[allanjude]

Fix wording

[bcr]

The text looks good to me as a first version. I think the change to the relnotes is unrelated?

website/content/en/releases/13.0R/relnotes.adoc

33

This change seems to be unrelated to the CPU freq change above.

[allanjude]

website/content/en/releases/13.0R/relnotes.adoc

33

yeah, fixing an excess /, I'll pull this out of this change

[allanjude]

Remove extraneous change

[allanjude]

Ed reports that hwpstate might not work on many Lenovo laptops, so we might need to add more detail and prominence to how to disable hwpstate and fall back to est(4)

[emaste]

I'm not completely familiar with the issue, but PR253288 has details
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=253288

[debdrup]

[source,shell] would indicate that a particular section using monospaced blocked text is a shell script.

I would also advise against including user@host and path et cetera, as the % prompt is used to indicate unprivileged commands and the # prompt to indicate privileged commands.

The rest of the documentation also follows this style.

Other than that, I have no issues with this, and am happy to see it. :)

[bcr]

Can we get this committed? Seems mostly complete to me.

[pauamma_gundo.com]

How much of this is applicable to (or has an equivalent for) AMD CPUs? If applicable to both amd64 branches, I'd mention it here and now. If there's separate support for a similar AMD-only feature, other review for documenting that?

(I know this request for changes is very late, but I'm only seeing this now.)

documentation/content/en/books/handbook/config/_index.adoc

1343

Here, I'd mention when to use EST and when to use Speed Shift. Something like: "For 12.x, always use EST. For 13.x, do what sysctl dev.cpufreq.(whatever).freq_driver tells you." Or however the decision tree runs.

1348

Trademarks on first use only. (Unless Intel wants them everywhere.)

1367

Clarify: what are SKUs?

1368

Or 13.x.

1369

What is %d here? Can some but not all CPUs in a computer support Speed Shift? (This sentence and the next one probably belong above in the "which to use" intro paragraph, not here.)

1381

See https://docs.freebsd.org/en/books/fdp-primer/asciidoctor-primer/#asciidoctor-primer-overview/ Also, what debdrup said: https://reviews.freebsd.org/D30004#673585 .

1389

[carlavilla]

@allanjude I'm gonna take this review and add it to the new config chapter.
@fernape was this precisely what you wanted to add, right?

[fernape]

In D30004#941521, @carlavilla wrote:

@allanjude I'm gonna take this review and add it to the new config chapter.
@fernape was this precisely what you wanted to add, right?

Yes, this is the information I was missing from the rework. This review is good, just needs a bit of tweaking.